From bad0d73b657412058c4d7773ff0d50291bfe1905 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Tue, 9 Jun 2020 14:45:03 +0100 Subject: [PATCH 01/20] firmware: arm_scmi: Use signed integer to report transfer status Currently the trace event 'scmi_xfer_end' reports the status of the transfer using the unsigned status field read from the firmware which may not be easy to interpret. It may also miss to emit any timeouts that happen in the driver resulting in emitting garbage in the status field in those scenarios. Let us use signed integer so that error values are emitted out after they are mapped from firmware error formats to standard linux error codes. While at this, also include any timeouts in the driver itself. Link: https://lore.kernel.org/r/20200609134503.55860-1-sudeep.holla@arm.com Cc: Jim Quinlan Cc: Lukasz Luba Reviewed-by: Lukasz Luba Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/driver.c | 3 +-- include/trace/events/scmi.h | 6 +++--- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 7483cacf63f9..136acbe2f4a1 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -392,8 +392,7 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) info->desc->ops->mark_txdone(cinfo, ret); trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, - xfer->hdr.protocol_id, xfer->hdr.seq, - xfer->hdr.status); + xfer->hdr.protocol_id, xfer->hdr.seq, ret); return ret; } diff --git a/include/trace/events/scmi.h b/include/trace/events/scmi.h index f076c430d243..f3a4b4d60714 100644 --- a/include/trace/events/scmi.h +++ b/include/trace/events/scmi.h @@ -35,7 +35,7 @@ TRACE_EVENT(scmi_xfer_begin, TRACE_EVENT(scmi_xfer_end, TP_PROTO(int transfer_id, u8 msg_id, u8 protocol_id, u16 seq, - u32 status), + int status), TP_ARGS(transfer_id, msg_id, protocol_id, seq, status), TP_STRUCT__entry( @@ -43,7 +43,7 @@ TRACE_EVENT(scmi_xfer_end, __field(u8, msg_id) __field(u8, protocol_id) __field(u16, seq) - __field(u32, status) + __field(int, status) ), TP_fast_assign( @@ -54,7 +54,7 @@ TRACE_EVENT(scmi_xfer_end, __entry->status = status; ), - TP_printk("transfer_id=%d msg_id=%u protocol_id=%u seq=%u status=%u", + TP_printk("transfer_id=%d msg_id=%u protocol_id=%u seq=%u status=%d", __entry->transfer_id, __entry->msg_id, __entry->protocol_id, __entry->seq, __entry->status) ); From 1909872ff20fc378ec6a44ea1a2b2966d834e504 Mon Sep 17 00:00:00 2001 From: Nicola Mazzucato Date: Wed, 17 Jun 2020 10:43:31 +0100 Subject: [PATCH 02/20] firmware: arm_scmi: Add fast_switch_possible() interface Add a new fast_switch_possible interface to the existing perf_ops to export the information of whether or not fast_switch is possible for a given device. This can be used by the cpufreq driver and framework to choose proper mechanism for frequency change. Link: https://lore.kernel.org/r/20200617094332.8391-1-nicola.mazzucato@arm.com Suggested-by: Lukasz Luba Signed-off-by: Nicola Mazzucato Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/perf.c | 12 ++++++++++++ include/linux/scmi_protocol.h | 2 ++ 2 files changed, 14 insertions(+) diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c index eadc171e254b..7b8d7cebdac9 100644 --- a/drivers/firmware/arm_scmi/perf.c +++ b/drivers/firmware/arm_scmi/perf.c @@ -697,6 +697,17 @@ static int scmi_dvfs_est_power_get(const struct scmi_handle *handle, u32 domain, return ret; } +static bool scmi_fast_switch_possible(const struct scmi_handle *handle, + struct device *dev) +{ + struct perf_dom_info *dom; + struct scmi_perf_info *pi = handle->perf_priv; + + dom = pi->dom_info + scmi_dev_domain_id(dev); + + return dom->fc_info && dom->fc_info->level_set_addr; +} + static struct scmi_perf_ops perf_ops = { .limits_set = scmi_perf_limits_set, .limits_get = scmi_perf_limits_get, @@ -708,6 +719,7 @@ static struct scmi_perf_ops perf_ops = { .freq_set = scmi_dvfs_freq_set, .freq_get = scmi_dvfs_freq_get, .est_power_get = scmi_dvfs_est_power_get, + .fast_switch_possible = scmi_fast_switch_possible, }; static int scmi_perf_protocol_init(struct scmi_handle *handle) diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index ce2f5c28b2df..73911d156a39 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -118,6 +118,8 @@ struct scmi_perf_ops { unsigned long *rate, bool poll); int (*est_power_get)(const struct scmi_handle *handle, u32 domain, unsigned long *rate, unsigned long *power); + bool (*fast_switch_possible)(const struct scmi_handle *handle, + struct device *dev); }; /** From fb3571276b970cbe7b45ecdc762e92f3f305ad6d Mon Sep 17 00:00:00 2001 From: Nicola Mazzucato Date: Wed, 17 Jun 2020 10:43:32 +0100 Subject: [PATCH 03/20] cpufreq: arm_scmi: Set fast_switch_possible conditionally Currently the fast_switch_possible flag is set unconditionally to true. Based on this, schedutil does not create a thread for frequency switching and would always use the fast switch path. However, if the platform does not support SCMI fast channel, we use polling mode for SCMI message transfer. This may be possible only if there is dedicated channel for DVFS and all operations are in polling mode. Update this by retrieving the fast_switch capability based on the presence of fast channels in SCMI platform firmware. Link: https://lore.kernel.org/r/20200617094332.8391-2-nicola.mazzucato@arm.com Suggested-by: Lukasz Luba Acked-by: Viresh Kumar Signed-off-by: Nicola Mazzucato Signed-off-by: Sudeep Holla --- drivers/cpufreq/scmi-cpufreq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 61623e2ff149..1cf688fcb56b 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -198,7 +198,8 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) policy->cpuinfo.transition_latency = latency; - policy->fast_switch_possible = true; + policy->fast_switch_possible = + handle->perf_ops->fast_switch_possible(handle, cpu_dev); em_register_perf_domain(policy->cpus, nr_opp, &em_cb); From d76428237784f703da821a5c1162b79d38acfd45 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 25 Jun 2020 11:19:37 +0100 Subject: [PATCH 04/20] firmware: arm_scmi: Use HAVE_ARM_SMCCC_DISCOVERY instead of ARM_PSCI_FW Commit e5bfb21d98b6 ("firmware: smccc: Add HAVE_ARM_SMCCC_DISCOVERY to identify SMCCC v1.1 and above") introduced new config option to identify the availability of SMCCC discoverability of version and features transparently hiding the indirect dependency on ARM_PSCI_FW. Commit 5a897e3ab429 ("firmware: arm_scmi: fix psci dependency") just worked around the build dependency making SCMI SMC/HVC transport depend on ARM_PSCI_FW at the time. Since it really just relies on SMCCC directly and not on ARM_PSCI_FW, let us move to use CONFIG_HAVE_ARM_SMCCC_DISCOVERY instead of CONFIG_ARM_PSCI_FW. Link: https://lore.kernel.org/r/20200625101937.51939-1-sudeep.holla@arm.com Cc: Peng Fan Cc: Arnd Bergmann Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/Makefile | 2 +- drivers/firmware/arm_scmi/driver.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile index 1cad32b38b29..70c5a8c986a5 100644 --- a/drivers/firmware/arm_scmi/Makefile +++ b/drivers/firmware/arm_scmi/Makefile @@ -4,6 +4,6 @@ scmi-bus-y = bus.o scmi-driver-y = driver.o scmi-transport-y = shmem.o scmi-transport-$(CONFIG_MAILBOX) += mailbox.o -scmi-transport-$(CONFIG_ARM_PSCI_FW) += smc.o +scmi-transport-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smc.o scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 136acbe2f4a1..a36a10b7b9d6 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -900,7 +900,7 @@ ATTRIBUTE_GROUPS(versions); /* Each compatible listed below must have descriptor associated with it */ static const struct of_device_id scmi_of_match[] = { { .compatible = "arm,scmi", .data = &scmi_mailbox_desc }, -#ifdef CONFIG_ARM_PSCI_FW +#ifdef CONFIG_HAVE_ARM_SMCCC_DISCOVERY { .compatible = "arm,scmi-smc", .data = &scmi_smc_desc}, #endif { /* Sentinel */ }, From e0f1a30cf184821499eeb67daedd7a3f21bbcb0b Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Fri, 19 Jun 2020 23:03:30 +0100 Subject: [PATCH 05/20] firmware: arm_scmi: Fix SCMI genpd domain probing When, at probe time, an SCMI communication failure inhibits the capacity to query power domains states, such domains should be skipped. Registering partially initialized SCMI power domains with genpd will causes kernel panic. arm-scmi timed out in resp(caller: scmi_power_state_get+0xa4/0xd0) scmi-power-domain scmi_dev.2: failed to get state for domain 9 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000009f3691000 [0000000000000000] pgd=00000009f1ca0003, p4d=00000009f1ca0003, pud=00000009f35ea003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] PREEMPT SMP CPU: 2 PID: 381 Comm: bash Not tainted 5.8.0-rc1-00011-gebd118c2cca8 #2 Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Jan 3 2020 Internal error: Oops: 96000006 [#1] PREEMPT SMP pstate: 80000005 (Nzcv daif -PAN -UAO BTYPE=--) pc : of_genpd_add_provider_onecell+0x98/0x1f8 lr : of_genpd_add_provider_onecell+0x48/0x1f8 Call trace: of_genpd_add_provider_onecell+0x98/0x1f8 scmi_pm_domain_probe+0x174/0x1e8 scmi_dev_probe+0x90/0xe0 really_probe+0xe4/0x448 driver_probe_device+0xfc/0x168 device_driver_attach+0x7c/0x88 bind_store+0xe8/0x128 drv_attr_store+0x2c/0x40 sysfs_kf_write+0x4c/0x60 kernfs_fop_write+0x114/0x230 __vfs_write+0x24/0x50 vfs_write+0xbc/0x1e0 ksys_write+0x70/0xf8 __arm64_sys_write+0x24/0x30 el0_svc_common.constprop.3+0x94/0x160 do_el0_svc+0x2c/0x98 el0_sync_handler+0x148/0x1a8 el0_sync+0x158/0x180 Do not register any power domain that failed to be queried with genpd. Fixes: 898216c97ed2 ("firmware: arm_scmi: add device power domain support using genpd") Link: https://lore.kernel.org/r/20200619220330.12217-1-cristian.marussi@arm.com Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/scmi_pm_domain.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/firmware/arm_scmi/scmi_pm_domain.c index bafbfe358f97..9e44479f0284 100644 --- a/drivers/firmware/arm_scmi/scmi_pm_domain.c +++ b/drivers/firmware/arm_scmi/scmi_pm_domain.c @@ -85,7 +85,10 @@ static int scmi_pm_domain_probe(struct scmi_device *sdev) for (i = 0; i < num_domains; i++, scmi_pd++) { u32 state; - domains[i] = &scmi_pd->genpd; + if (handle->power_ops->state_get(handle, i, &state)) { + dev_warn(dev, "failed to get state for domain %d\n", i); + continue; + } scmi_pd->domain = i; scmi_pd->handle = handle; @@ -94,13 +97,10 @@ static int scmi_pm_domain_probe(struct scmi_device *sdev) scmi_pd->genpd.power_off = scmi_pd_power_off; scmi_pd->genpd.power_on = scmi_pd_power_on; - if (handle->power_ops->state_get(handle, i, &state)) { - dev_warn(dev, "failed to get state for domain %d\n", i); - continue; - } - pm_genpd_init(&scmi_pd->genpd, NULL, state == SCMI_POWER_STATE_GENERIC_OFF); + + domains[i] = &scmi_pd->genpd; } scmi_pd_data->domains = domains; From 1fc2dd1864c2b18860fb619caeee758504c3aac8 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:40 +0100 Subject: [PATCH 06/20] firmware: arm_scmi: Add notification protocol-registration Add the core SCMI notifications protocol-registration support: allow protocols to register their own set of supported events, during their initialization phase. Notification core can track multiple platform instances by their handles. Link: https://lore.kernel.org/r/20200701155348.52864-2-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/Makefile | 2 +- drivers/firmware/arm_scmi/common.h | 4 + drivers/firmware/arm_scmi/notify.c | 440 +++++++++++++++++++++++++++++ drivers/firmware/arm_scmi/notify.h | 56 ++++ include/linux/scmi_protocol.h | 3 + 5 files changed, 504 insertions(+), 1 deletion(-) create mode 100644 drivers/firmware/arm_scmi/notify.c create mode 100644 drivers/firmware/arm_scmi/notify.h diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile index 70c5a8c986a5..6f9cbc4aef22 100644 --- a/drivers/firmware/arm_scmi/Makefile +++ b/drivers/firmware/arm_scmi/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only obj-y = scmi-bus.o scmi-driver.o scmi-protocols.o scmi-transport.o scmi-bus-y = bus.o -scmi-driver-y = driver.o +scmi-driver-y = driver.o notify.o scmi-transport-y = shmem.o scmi-transport-$(CONFIG_MAILBOX) += mailbox.o scmi-transport-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smc.o diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 31fe5a22a011..c113e578cc6c 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -6,6 +6,8 @@ * * Copyright (C) 2018 ARM Ltd. */ +#ifndef _SCMI_COMMON_H +#define _SCMI_COMMON_H #include #include @@ -235,3 +237,5 @@ void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem, void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem); bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem, struct scmi_xfer *xfer); + +#endif /* _SCMI_COMMON_H */ diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c new file mode 100644 index 000000000000..0505433043d8 --- /dev/null +++ b/drivers/firmware/arm_scmi/notify.c @@ -0,0 +1,440 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface (SCMI) Notification support + * + * Copyright (C) 2020 ARM Ltd. + */ +/** + * DOC: Theory of operation + * + * SCMI Protocol specification allows the platform to signal events to + * interested agents via notification messages: this is an implementation + * of the dispatch and delivery of such notifications to the interested users + * inside the Linux kernel. + * + * An SCMI Notification core instance is initialized for each active platform + * instance identified by the means of the usual &struct scmi_handle. + * + * Each SCMI Protocol implementation, during its initialization, registers with + * this core its set of supported events using scmi_register_protocol_events(): + * all the needed descriptors are stored in the &struct registered_protocols and + * &struct registered_events arrays. + */ + +#define dev_fmt(fmt) "SCMI Notifications - " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "notify.h" + +#define SCMI_MAX_PROTO 256 + +#define PROTO_ID_MASK GENMASK(31, 24) +#define EVT_ID_MASK GENMASK(23, 16) +#define SRC_ID_MASK GENMASK(15, 0) + +/* + * Builds an unsigned 32bit key from the given input tuple to be used + * as a key in hashtables. + */ +#define MAKE_HASH_KEY(p, e, s) \ + (FIELD_PREP(PROTO_ID_MASK, (p)) | \ + FIELD_PREP(EVT_ID_MASK, (e)) | \ + FIELD_PREP(SRC_ID_MASK, (s))) + +#define MAKE_ALL_SRCS_KEY(p, e) MAKE_HASH_KEY((p), (e), SRC_ID_MASK) + +struct scmi_registered_events_desc; + +/** + * struct scmi_notify_instance - Represents an instance of the notification + * core + * @gid: GroupID used for devres + * @handle: A reference to the platform instance + * @registered_protocols: A statically allocated array containing pointers to + * all the registered protocol-level specific information + * related to events' handling + * + * Each platform instance, represented by a handle, has its own instance of + * the notification subsystem represented by this structure. + */ +struct scmi_notify_instance { + void *gid; + struct scmi_handle *handle; + struct scmi_registered_events_desc **registered_protocols; +}; + +/** + * struct events_queue - Describes a queue and its associated worker + * @sz: Size in bytes of the related kfifo + * @kfifo: A dedicated Kernel kfifo descriptor + * + * Each protocol has its own dedicated events_queue descriptor. + */ +struct events_queue { + size_t sz; + struct kfifo kfifo; +}; + +/** + * struct scmi_event_header - A utility header + * @timestamp: The timestamp, in nanoseconds (boottime), which was associated + * to this event as soon as it entered the SCMI RX ISR + * @evt_id: Event ID (corresponds to the Event MsgID for this Protocol) + * @payld_sz: Effective size of the embedded message payload which follows + * @payld: A reference to the embedded event payload + * + * This header is prepended to each received event message payload before + * queueing it on the related &struct events_queue. + */ +struct scmi_event_header { + u64 timestamp; + u8 evt_id; + size_t payld_sz; + u8 payld[]; +} __packed; + +struct scmi_registered_event; + +/** + * struct scmi_registered_events_desc - Protocol Specific information + * @id: Protocol ID + * @ops: Protocol specific and event-related operations + * @equeue: The embedded per-protocol events_queue + * @ni: A reference to the initialized instance descriptor + * @eh: A reference to pre-allocated buffer to be used as a scratch area by the + * deferred worker when fetching data from the kfifo + * @eh_sz: Size of the pre-allocated buffer @eh + * @in_flight: A reference to an in flight &struct scmi_registered_event + * @num_events: Number of events in @registered_events + * @registered_events: A dynamically allocated array holding all the registered + * events' descriptors, whose fixed-size is determined at + * compile time. + * + * All protocols that register at least one event have their protocol-specific + * information stored here, together with the embedded allocated events_queue. + * These descriptors are stored in the @registered_protocols array at protocol + * registration time. + * + * Once these descriptors are successfully registered, they are NEVER again + * removed or modified since protocols do not unregister ever, so that, once + * we safely grab a NON-NULL reference from the array we can keep it and use it. + */ +struct scmi_registered_events_desc { + u8 id; + const struct scmi_event_ops *ops; + struct events_queue equeue; + struct scmi_notify_instance *ni; + struct scmi_event_header *eh; + size_t eh_sz; + void *in_flight; + int num_events; + struct scmi_registered_event **registered_events; +}; + +/** + * struct scmi_registered_event - Event Specific Information + * @proto: A reference to the associated protocol descriptor + * @evt: A reference to the associated event descriptor (as provided at + * registration time) + * @report: A pre-allocated buffer used by the deferred worker to fill a + * customized event report + * @num_sources: The number of possible sources for this event as stated at + * events' registration time + * @sources: A reference to a dynamically allocated array used to refcount the + * events' enable requests for all the existing sources + * @sources_mtx: A mutex to serialize the access to @sources + * + * All registered events are represented by one of these structures that are + * stored in the @registered_events array at protocol registration time. + * + * Once these descriptors are successfully registered, they are NEVER again + * removed or modified since protocols do not unregister ever, so that once we + * safely grab a NON-NULL reference from the table we can keep it and use it. + */ +struct scmi_registered_event { + struct scmi_registered_events_desc *proto; + const struct scmi_event *evt; + void *report; + u32 num_sources; + refcount_t *sources; + /* locking to serialize the access to sources */ + struct mutex sources_mtx; +}; + +/** + * scmi_kfifo_free() - Devres action helper to free the kfifo + * @kfifo: The kfifo to free + */ +static void scmi_kfifo_free(void *kfifo) +{ + kfifo_free((struct kfifo *)kfifo); +} + +/** + * scmi_initialize_events_queue() - Allocate/Initialize a kfifo buffer + * @ni: A reference to the notification instance to use + * @equeue: The events_queue to initialize + * @sz: Size of the kfifo buffer to allocate + * + * Allocate a buffer for the kfifo and initialize it. + * + * Return: 0 on Success + */ +static int scmi_initialize_events_queue(struct scmi_notify_instance *ni, + struct events_queue *equeue, size_t sz) +{ + if (kfifo_alloc(&equeue->kfifo, sz, GFP_KERNEL)) + return -ENOMEM; + /* Size could have been roundup to power-of-two */ + equeue->sz = kfifo_size(&equeue->kfifo); + + return devm_add_action_or_reset(ni->handle->dev, scmi_kfifo_free, + &equeue->kfifo); +} + +/** + * scmi_allocate_registered_events_desc() - Allocate a registered events' + * descriptor + * @ni: A reference to the &struct scmi_notify_instance notification instance + * to use + * @proto_id: Protocol ID + * @queue_sz: Size of the associated queue to allocate + * @eh_sz: Size of the event header scratch area to pre-allocate + * @num_events: Number of events to support (size of @registered_events) + * @ops: Pointer to a struct holding references to protocol specific helpers + * needed during events handling + * + * It is supposed to be called only once for each protocol at protocol + * initialization time, so it warns if the requested protocol is found already + * registered. + * + * Return: The allocated and registered descriptor on Success + */ +static struct scmi_registered_events_desc * +scmi_allocate_registered_events_desc(struct scmi_notify_instance *ni, + u8 proto_id, size_t queue_sz, size_t eh_sz, + int num_events, + const struct scmi_event_ops *ops) +{ + int ret; + struct scmi_registered_events_desc *pd; + + /* Ensure protocols are up to date */ + smp_rmb(); + if (WARN_ON(ni->registered_protocols[proto_id])) + return ERR_PTR(-EINVAL); + + pd = devm_kzalloc(ni->handle->dev, sizeof(*pd), GFP_KERNEL); + if (!pd) + return ERR_PTR(-ENOMEM); + pd->id = proto_id; + pd->ops = ops; + pd->ni = ni; + + ret = scmi_initialize_events_queue(ni, &pd->equeue, queue_sz); + if (ret) + return ERR_PTR(ret); + + pd->eh = devm_kzalloc(ni->handle->dev, eh_sz, GFP_KERNEL); + if (!pd->eh) + return ERR_PTR(-ENOMEM); + pd->eh_sz = eh_sz; + + pd->registered_events = devm_kcalloc(ni->handle->dev, num_events, + sizeof(char *), GFP_KERNEL); + if (!pd->registered_events) + return ERR_PTR(-ENOMEM); + pd->num_events = num_events; + + return pd; +} + +/** + * scmi_register_protocol_events() - Register Protocol Events with the core + * @handle: The handle identifying the platform instance against which the + * the protocol's events are registered + * @proto_id: Protocol ID + * @queue_sz: Size in bytes of the associated queue to be allocated + * @ops: Protocol specific event-related operations + * @evt: Event descriptor array + * @num_events: Number of events in @evt array + * @num_sources: Number of possible sources for this protocol on this + * platform. + * + * Used by SCMI Protocols initialization code to register with the notification + * core the list of supported events and their descriptors: takes care to + * pre-allocate and store all needed descriptors, scratch buffers and event + * queues. + * + * Return: 0 on Success + */ +int scmi_register_protocol_events(const struct scmi_handle *handle, + u8 proto_id, size_t queue_sz, + const struct scmi_event_ops *ops, + const struct scmi_event *evt, int num_events, + int num_sources) +{ + int i; + size_t payld_sz = 0; + struct scmi_registered_events_desc *pd; + struct scmi_notify_instance *ni; + + if (!ops || !evt) + return -EINVAL; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return -ENOMEM; + ni = handle->notify_priv; + + /* Attach to the notification main devres group */ + if (!devres_open_group(ni->handle->dev, ni->gid, GFP_KERNEL)) + return -ENOMEM; + + for (i = 0; i < num_events; i++) + payld_sz = max_t(size_t, payld_sz, evt[i].max_payld_sz); + payld_sz += sizeof(struct scmi_event_header); + + pd = scmi_allocate_registered_events_desc(ni, proto_id, queue_sz, + payld_sz, num_events, ops); + if (IS_ERR(pd)) + goto err; + + for (i = 0; i < num_events; i++, evt++) { + struct scmi_registered_event *r_evt; + + r_evt = devm_kzalloc(ni->handle->dev, sizeof(*r_evt), + GFP_KERNEL); + if (!r_evt) + goto err; + r_evt->proto = pd; + r_evt->evt = evt; + + r_evt->sources = devm_kcalloc(ni->handle->dev, num_sources, + sizeof(refcount_t), GFP_KERNEL); + if (!r_evt->sources) + goto err; + r_evt->num_sources = num_sources; + mutex_init(&r_evt->sources_mtx); + + r_evt->report = devm_kzalloc(ni->handle->dev, + evt->max_report_sz, GFP_KERNEL); + if (!r_evt->report) + goto err; + + pd->registered_events[i] = r_evt; + /* Ensure events are updated */ + smp_wmb(); + dev_dbg(handle->dev, "registered event - %lX\n", + MAKE_ALL_SRCS_KEY(r_evt->proto->id, r_evt->evt->id)); + } + + /* Register protocol and events...it will never be removed */ + ni->registered_protocols[proto_id] = pd; + /* Ensure protocols are updated */ + smp_wmb(); + + devres_close_group(ni->handle->dev, ni->gid); + + return 0; + +err: + dev_warn(handle->dev, "Proto:%X - Registration Failed !\n", proto_id); + /* A failing protocol registration does not trigger full failure */ + devres_close_group(ni->handle->dev, ni->gid); + + return -ENOMEM; +} + +/** + * scmi_notification_init() - Initializes Notification Core Support + * @handle: The handle identifying the platform instance to initialize + * + * This function lays out all the basic resources needed by the notification + * core instance identified by the provided handle: once done, all of the + * SCMI Protocols can register their events with the core during their own + * initializations. + * + * Note that failing to initialize the core notifications support does not + * cause the whole SCMI Protocols stack to fail its initialization. + * + * SCMI Notification Initialization happens in 2 steps: + * * initialization: basic common allocations (this function) + * * registration: protocols asynchronously come into life and registers their + * own supported list of events with the core; this causes + * further per-protocol allocations + * + * Any user's callback registration attempt, referring a still not registered + * event, will be registered as pending and finalized later (if possible) + * by scmi_protocols_late_init() work. + * This allows for lazy initialization of SCMI Protocols due to late (or + * missing) SCMI drivers' modules loading. + * + * Return: 0 on Success + */ +int scmi_notification_init(struct scmi_handle *handle) +{ + void *gid; + struct scmi_notify_instance *ni; + + gid = devres_open_group(handle->dev, NULL, GFP_KERNEL); + if (!gid) + return -ENOMEM; + + ni = devm_kzalloc(handle->dev, sizeof(*ni), GFP_KERNEL); + if (!ni) + goto err; + + ni->gid = gid; + ni->handle = handle; + + ni->registered_protocols = devm_kcalloc(handle->dev, SCMI_MAX_PROTO, + sizeof(char *), GFP_KERNEL); + if (!ni->registered_protocols) + goto err; + + handle->notify_priv = ni; + /* Ensure handle is up to date */ + smp_wmb(); + + dev_info(handle->dev, "Core Enabled.\n"); + + devres_close_group(handle->dev, ni->gid); + + return 0; + +err: + dev_warn(handle->dev, "Initialization Failed.\n"); + devres_release_group(handle->dev, NULL); + return -ENOMEM; +} + +/** + * scmi_notification_exit() - Shutdown and clean Notification core + * @handle: The handle identifying the platform instance to shutdown + */ +void scmi_notification_exit(struct scmi_handle *handle) +{ + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return; + ni = handle->notify_priv; + + devres_release_group(ni->handle->dev, ni->gid); +} diff --git a/drivers/firmware/arm_scmi/notify.h b/drivers/firmware/arm_scmi/notify.h new file mode 100644 index 000000000000..48702e42995f --- /dev/null +++ b/drivers/firmware/arm_scmi/notify.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * System Control and Management Interface (SCMI) Message Protocol + * notification header file containing some definitions, structures + * and function prototypes related to SCMI Notification handling. + * + * Copyright (C) 2020 ARM Ltd. + */ +#ifndef _SCMI_NOTIFY_H +#define _SCMI_NOTIFY_H + +#include +#include + +#define SCMI_PROTO_QUEUE_SZ 4096 + +/** + * struct scmi_event - Describes an event to be supported + * @id: Event ID + * @max_payld_sz: Max possible size for the payload of a notification message + * @max_report_sz: Max possible size for the report of a notification message + * + * Each SCMI protocol, during its initialization phase, can describe the events + * it wishes to support in a few struct scmi_event and pass them to the core + * using scmi_register_protocol_events(). + */ +struct scmi_event { + u8 id; + size_t max_payld_sz; + size_t max_report_sz; +}; + +/** + * struct scmi_event_ops - Protocol helpers called by the notification core. + * @set_notify_enabled: Enable/disable the required evt_id/src_id notifications + * using the proper custom protocol commands. + * Return 0 on Success + * + * Context: Helpers described in &struct scmi_event_ops are called only in + * process context. + */ +struct scmi_event_ops { + int (*set_notify_enabled)(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enabled); +}; + +int scmi_notification_init(struct scmi_handle *handle); +void scmi_notification_exit(struct scmi_handle *handle); + +int scmi_register_protocol_events(const struct scmi_handle *handle, + u8 proto_id, size_t queue_sz, + const struct scmi_event_ops *ops, + const struct scmi_event *evt, int num_events, + int num_sources); + +#endif /* _SCMI_NOTIFY_H */ diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 73911d156a39..9a34b02a9cce 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -233,6 +233,8 @@ struct scmi_reset_ops { * protocol(for internal use only) * @reset_priv: pointer to private data structure specific to reset * protocol(for internal use only) + * @notify_priv: pointer to private data structure specific to notifications + * (for internal use only) */ struct scmi_handle { struct device *dev; @@ -248,6 +250,7 @@ struct scmi_handle { void *power_priv; void *sensor_priv; void *reset_priv; + void *notify_priv; }; enum scmi_std_protocol { From e7c215f358a350c4bc326b9cea86763f480a97f9 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:41 +0100 Subject: [PATCH 07/20] firmware: arm_scmi: Add notification callbacks-registration Add the core SCMI notifications callbacks-registration support: allow users to register their own callbacks against the desired events. Whenever a registration request is issued against a still non existent event, mark such request as pending for later processing, in order to account for possible late initializations of SCMI Protocols associated to loadable drivers. Link: https://lore.kernel.org/r/20200701155348.52864-3-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/notify.c | 726 +++++++++++++++++++++++++++++ include/linux/scmi_protocol.h | 46 ++ 2 files changed, 772 insertions(+) diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c index 0505433043d8..79615eef0148 100644 --- a/drivers/firmware/arm_scmi/notify.c +++ b/drivers/firmware/arm_scmi/notify.c @@ -19,18 +19,50 @@ * this core its set of supported events using scmi_register_protocol_events(): * all the needed descriptors are stored in the &struct registered_protocols and * &struct registered_events arrays. + * + * Kernel users interested in some specific event can register their callbacks + * providing the usual notifier_block descriptor, since this core implements + * events' delivery using the standard Kernel notification chains machinery. + * + * Given the number of possible events defined by SCMI and the extensibility + * of the SCMI Protocol itself, the underlying notification chains are created + * and destroyed dynamically on demand depending on the number of users + * effectively registered for an event, so that no support structures or chains + * are allocated until at least one user has registered a notifier_block for + * such event. Similarly, events' generation itself is enabled at the platform + * level only after at least one user has registered, and it is shutdown after + * the last user for that event has gone. + * + * All users provided callbacks and allocated notification-chains are stored in + * the @registered_events_handlers hashtable. Callbacks' registration requests + * for still to be registered events are instead kept in the dedicated common + * hashtable @pending_events_handlers. + * + * An event is identified univocally by the tuple (proto_id, evt_id, src_id) + * and is served by its own dedicated notification chain; information contained + * in such tuples is used, in a few different ways, to generate the needed + * hash-keys. + * + * Here proto_id and evt_id are simply the protocol_id and message_id numbers + * as described in the SCMI Protocol specification, while src_id represents an + * optional, protocol dependent, source identifier (like domain_id, perf_id + * or sensor_id and so forth). */ #define dev_fmt(fmt) "SCMI Notifications - " fmt +#define pr_fmt(fmt) "SCMI Notifications - " fmt #include #include #include #include #include +#include #include #include +#include #include +#include #include #include #include @@ -55,6 +87,86 @@ #define MAKE_ALL_SRCS_KEY(p, e) MAKE_HASH_KEY((p), (e), SRC_ID_MASK) +/* + * Assumes that the stored obj includes its own hash-key in a field named 'key': + * with this simplification this macro can be equally used for all the objects' + * types hashed by this implementation. + * + * @__ht: The hashtable name + * @__obj: A pointer to the object type to be retrieved from the hashtable; + * it will be used as a cursor while scanning the hastable and it will + * be possibly left as NULL when @__k is not found + * @__k: The key to search for + */ +#define KEY_FIND(__ht, __obj, __k) \ +({ \ + typeof(__k) k_ = __k; \ + typeof(__obj) obj_; \ + \ + hash_for_each_possible((__ht), obj_, hash, k_) \ + if (obj_->key == k_) \ + break; \ + __obj = obj_; \ +}) + +#define KEY_XTRACT_PROTO_ID(key) FIELD_GET(PROTO_ID_MASK, (key)) +#define KEY_XTRACT_EVT_ID(key) FIELD_GET(EVT_ID_MASK, (key)) +#define KEY_XTRACT_SRC_ID(key) FIELD_GET(SRC_ID_MASK, (key)) + +/* + * A set of macros used to access safely @registered_protocols and + * @registered_events arrays; these are fixed in size and each entry is possibly + * populated at protocols' registration time and then only read but NEVER + * modified or removed. + */ +#define SCMI_GET_PROTO(__ni, __pid) \ +({ \ + typeof(__ni) ni_ = __ni; \ + struct scmi_registered_events_desc *__pd = NULL; \ + \ + if (ni_) \ + __pd = READ_ONCE(ni_->registered_protocols[(__pid)]); \ + __pd; \ +}) + +#define SCMI_GET_REVT_FROM_PD(__pd, __eid) \ +({ \ + typeof(__pd) pd_ = __pd; \ + typeof(__eid) eid_ = __eid; \ + struct scmi_registered_event *__revt = NULL; \ + \ + if (pd_ && eid_ < pd_->num_events) \ + __revt = READ_ONCE(pd_->registered_events[eid_]); \ + __revt; \ +}) + +#define SCMI_GET_REVT(__ni, __pid, __eid) \ +({ \ + struct scmi_registered_event *__revt; \ + struct scmi_registered_events_desc *__pd; \ + \ + __pd = SCMI_GET_PROTO((__ni), (__pid)); \ + __revt = SCMI_GET_REVT_FROM_PD(__pd, (__eid)); \ + __revt; \ +}) + +/* A couple of utility macros to limit cruft when calling protocols' helpers */ +#define REVT_NOTIFY_SET_STATUS(revt, eid, sid, state) \ +({ \ + typeof(revt) r = revt; \ + r->proto->ops->set_notify_enabled(r->proto->ni->handle, \ + (eid), (sid), (state)); \ +}) + +#define REVT_NOTIFY_ENABLE(revt, eid, sid) \ + REVT_NOTIFY_SET_STATUS((revt), (eid), (sid), true) + +#define REVT_NOTIFY_DISABLE(revt, eid, sid) \ + REVT_NOTIFY_SET_STATUS((revt), (eid), (sid), false) + +#define SCMI_PENDING_HASH_SZ 4 +#define SCMI_REGISTERED_HASH_SZ 6 + struct scmi_registered_events_desc; /** @@ -62,9 +174,13 @@ struct scmi_registered_events_desc; * core * @gid: GroupID used for devres * @handle: A reference to the platform instance + * @init_work: A work item to perform final initializations of pending handlers + * @pending_mtx: A mutex to protect @pending_events_handlers * @registered_protocols: A statically allocated array containing pointers to * all the registered protocol-level specific information * related to events' handling + * @pending_events_handlers: An hashtable containing all pending events' + * handlers descriptors * * Each platform instance, represented by a handle, has its own instance of * the notification subsystem represented by this structure. @@ -72,7 +188,11 @@ struct scmi_registered_events_desc; struct scmi_notify_instance { void *gid; struct scmi_handle *handle; + struct work_struct init_work; + /* lock to protect pending_events_handlers */ + struct mutex pending_mtx; struct scmi_registered_events_desc **registered_protocols; + DECLARE_HASHTABLE(pending_events_handlers, SCMI_PENDING_HASH_SZ); }; /** @@ -121,6 +241,9 @@ struct scmi_registered_event; * @registered_events: A dynamically allocated array holding all the registered * events' descriptors, whose fixed-size is determined at * compile time. + * @registered_mtx: A mutex to protect @registered_events_handlers + * @registered_events_handlers: An hashtable containing all events' handlers + * descriptors registered for this protocol * * All protocols that register at least one event have their protocol-specific * information stored here, together with the embedded allocated events_queue. @@ -141,6 +264,9 @@ struct scmi_registered_events_desc { void *in_flight; int num_events; struct scmi_registered_event **registered_events; + /* mutex to protect registered_events_handlers */ + struct mutex registered_mtx; + DECLARE_HASHTABLE(registered_events_handlers, SCMI_REGISTERED_HASH_SZ); }; /** @@ -173,6 +299,38 @@ struct scmi_registered_event { struct mutex sources_mtx; }; +/** + * struct scmi_event_handler - Event handler information + * @key: The used hashkey + * @users: A reference count for number of active users for this handler + * @r_evt: A reference to the associated registered event; when this is NULL + * this handler is pending, which means that identifies a set of + * callbacks intended to be attached to an event which is still not + * known nor registered by any protocol at that point in time + * @chain: The notification chain dedicated to this specific event tuple + * @hash: The hlist_node used for collision handling + * @enabled: A boolean which records if event's generation has been already + * enabled for this handler as a whole + * + * This structure collects all the information needed to process a received + * event identified by the tuple (proto_id, evt_id, src_id). + * These descriptors are stored in a per-protocol @registered_events_handlers + * table using as a key a value derived from that tuple. + */ +struct scmi_event_handler { + u32 key; + refcount_t users; + struct scmi_registered_event *r_evt; + struct blocking_notifier_head chain; + struct hlist_node hash; + bool enabled; +}; + +#define IS_HNDL_PENDING(hndl) (!(hndl)->r_evt) + +static void scmi_put_handler_unlocked(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl); + /** * scmi_kfifo_free() - Devres action helper to free the kfifo * @kfifo: The kfifo to free @@ -258,6 +416,10 @@ scmi_allocate_registered_events_desc(struct scmi_notify_instance *ni, return ERR_PTR(-ENOMEM); pd->num_events = num_events; + /* Initialize per protocol handlers table */ + mutex_init(&pd->registered_mtx); + hash_init(pd->registered_events_handlers); + return pd; } @@ -349,6 +511,12 @@ int scmi_register_protocol_events(const struct scmi_handle *handle, devres_close_group(ni->handle->dev, ni->gid); + /* + * Finalize any pending events' handler which could have been waiting + * for this protocol's events registration. + */ + schedule_work(&ni->init_work); + return 0; err: @@ -359,6 +527,558 @@ err: return -ENOMEM; } +/** + * scmi_allocate_event_handler() - Allocate Event handler + * @ni: A reference to the notification instance to use + * @evt_key: 32bit key uniquely bind to the event identified by the tuple + * (proto_id, evt_id, src_id) + * + * Allocate an event handler and related notification chain associated with + * the provided event handler key. + * Note that, at this point, a related registered_event is still to be + * associated to this handler descriptor (hndl->r_evt == NULL), so the handler + * is initialized as pending. + * + * Context: Assumes to be called with @pending_mtx already acquired. + * Return: the freshly allocated structure on Success + */ +static struct scmi_event_handler * +scmi_allocate_event_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + struct scmi_event_handler *hndl; + + hndl = kzalloc(sizeof(*hndl), GFP_KERNEL); + if (!hndl) + return NULL; + hndl->key = evt_key; + BLOCKING_INIT_NOTIFIER_HEAD(&hndl->chain); + refcount_set(&hndl->users, 1); + /* New handlers are created pending */ + hash_add(ni->pending_events_handlers, &hndl->hash, hndl->key); + + return hndl; +} + +/** + * scmi_free_event_handler() - Free the provided Event handler + * @hndl: The event handler structure to free + * + * Context: Assumes to be called with proper locking acquired depending + * on the situation. + */ +static void scmi_free_event_handler(struct scmi_event_handler *hndl) +{ + hash_del(&hndl->hash); + kfree(hndl); +} + +/** + * scmi_bind_event_handler() - Helper to attempt binding an handler to an event + * @ni: A reference to the notification instance to use + * @hndl: The event handler to bind + * + * If an associated registered event is found, move the handler from the pending + * into the registered table. + * + * Context: Assumes to be called with @pending_mtx already acquired. + * + * Return: 0 on Success + */ +static inline int scmi_bind_event_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_event *r_evt; + + r_evt = SCMI_GET_REVT(ni, KEY_XTRACT_PROTO_ID(hndl->key), + KEY_XTRACT_EVT_ID(hndl->key)); + if (!r_evt) + return -EINVAL; + + /* Remove from pending and insert into registered */ + hash_del(&hndl->hash); + hndl->r_evt = r_evt; + mutex_lock(&r_evt->proto->registered_mtx); + hash_add(r_evt->proto->registered_events_handlers, + &hndl->hash, hndl->key); + mutex_unlock(&r_evt->proto->registered_mtx); + + return 0; +} + +/** + * scmi_valid_pending_handler() - Helper to check pending status of handlers + * @ni: A reference to the notification instance to use + * @hndl: The event handler to check + * + * An handler is considered pending when its r_evt == NULL, because the related + * event was still unknown at handler's registration time; anyway, since all + * protocols register their supported events once for all at protocols' + * initialization time, a pending handler cannot be considered valid anymore if + * the underlying event (which it is waiting for), belongs to an already + * initialized and registered protocol. + * + * Return: 0 on Success + */ +static inline int scmi_valid_pending_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_events_desc *pd; + + if (!IS_HNDL_PENDING(hndl)) + return -EINVAL; + + pd = SCMI_GET_PROTO(ni, KEY_XTRACT_PROTO_ID(hndl->key)); + if (pd) + return -EINVAL; + + return 0; +} + +/** + * scmi_register_event_handler() - Register whenever possible an Event handler + * @ni: A reference to the notification instance to use + * @hndl: The event handler to register + * + * At first try to bind an event handler to its associated event, then check if + * it was at least a valid pending handler: if it was not bound nor valid return + * false. + * + * Valid pending incomplete bindings will be periodically retried by a dedicated + * worker which is kicked each time a new protocol completes its own + * registration phase. + * + * Context: Assumes to be called with @pending_mtx acquired. + * + * Return: 0 on Success + */ +static int scmi_register_event_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + int ret; + + ret = scmi_bind_event_handler(ni, hndl); + if (!ret) { + dev_dbg(ni->handle->dev, "registered NEW handler - key:%X\n", + hndl->key); + } else { + ret = scmi_valid_pending_handler(ni, hndl); + if (!ret) + dev_dbg(ni->handle->dev, + "registered PENDING handler - key:%X\n", + hndl->key); + } + + return ret; +} + +/** + * __scmi_event_handler_get_ops() - Utility to get or create an event handler + * @ni: A reference to the notification instance to use + * @evt_key: The event key to use + * @create: A boolean flag to specify if a handler must be created when + * not already existent + * + * Search for the desired handler matching the key in both the per-protocol + * registered table and the common pending table: + * * if found adjust users refcount + * * if not found and @create is true, create and register the new handler: + * handler could end up being registered as pending if no matching event + * could be found. + * + * An handler is guaranteed to reside in one and only one of the tables at + * any one time; to ensure this the whole search and create is performed + * holding the @pending_mtx lock, with @registered_mtx additionally acquired + * if needed. + * + * Note that when a nested acquisition of these mutexes is needed the locking + * order is always (same as in @init_work): + * 1. pending_mtx + * 2. registered_mtx + * + * Events generation is NOT enabled right after creation within this routine + * since at creation time we usually want to have all setup and ready before + * events really start flowing. + * + * Return: A properly refcounted handler on Success, NULL on Failure + */ +static inline struct scmi_event_handler * +__scmi_event_handler_get_ops(struct scmi_notify_instance *ni, + u32 evt_key, bool create) +{ + struct scmi_registered_event *r_evt; + struct scmi_event_handler *hndl = NULL; + + r_evt = SCMI_GET_REVT(ni, KEY_XTRACT_PROTO_ID(evt_key), + KEY_XTRACT_EVT_ID(evt_key)); + + mutex_lock(&ni->pending_mtx); + /* Search registered events at first ... if possible at all */ + if (r_evt) { + mutex_lock(&r_evt->proto->registered_mtx); + hndl = KEY_FIND(r_evt->proto->registered_events_handlers, + hndl, evt_key); + if (hndl) + refcount_inc(&hndl->users); + mutex_unlock(&r_evt->proto->registered_mtx); + } + + /* ...then amongst pending. */ + if (!hndl) { + hndl = KEY_FIND(ni->pending_events_handlers, hndl, evt_key); + if (hndl) + refcount_inc(&hndl->users); + } + + /* Create if still not found and required */ + if (!hndl && create) { + hndl = scmi_allocate_event_handler(ni, evt_key); + if (hndl && scmi_register_event_handler(ni, hndl)) { + dev_dbg(ni->handle->dev, + "purging UNKNOWN handler - key:%X\n", + hndl->key); + /* this hndl can be only a pending one */ + scmi_put_handler_unlocked(ni, hndl); + hndl = NULL; + } + } + mutex_unlock(&ni->pending_mtx); + + return hndl; +} + +static struct scmi_event_handler * +scmi_get_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + return __scmi_event_handler_get_ops(ni, evt_key, false); +} + +static struct scmi_event_handler * +scmi_get_or_create_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + return __scmi_event_handler_get_ops(ni, evt_key, true); +} + +/** + * __scmi_enable_evt() - Enable/disable events generation + * @r_evt: The registered event to act upon + * @src_id: The src_id to act upon + * @enable: The action to perform: true->Enable, false->Disable + * + * Takes care of proper refcounting while performing enable/disable: handles + * the special case of ALL sources requests by itself. + * Returns successfully if at least one of the required src_id has been + * successfully enabled/disabled. + * + * Return: 0 on Success + */ +static inline int __scmi_enable_evt(struct scmi_registered_event *r_evt, + u32 src_id, bool enable) +{ + int retvals = 0; + u32 num_sources; + refcount_t *sid; + + if (src_id == SRC_ID_MASK) { + src_id = 0; + num_sources = r_evt->num_sources; + } else if (src_id < r_evt->num_sources) { + num_sources = 1; + } else { + return -EINVAL; + } + + mutex_lock(&r_evt->sources_mtx); + if (enable) { + for (; num_sources; src_id++, num_sources--) { + int ret = 0; + + sid = &r_evt->sources[src_id]; + if (refcount_read(sid) == 0) { + ret = REVT_NOTIFY_ENABLE(r_evt, r_evt->evt->id, + src_id); + if (!ret) + refcount_set(sid, 1); + } else { + refcount_inc(sid); + } + retvals += !ret; + } + } else { + for (; num_sources; src_id++, num_sources--) { + sid = &r_evt->sources[src_id]; + if (refcount_dec_and_test(sid)) + REVT_NOTIFY_DISABLE(r_evt, + r_evt->evt->id, src_id); + } + retvals = 1; + } + mutex_unlock(&r_evt->sources_mtx); + + return retvals ? 0 : -EINVAL; +} + +static int scmi_enable_events(struct scmi_event_handler *hndl) +{ + int ret = 0; + + if (!hndl->enabled) { + ret = __scmi_enable_evt(hndl->r_evt, + KEY_XTRACT_SRC_ID(hndl->key), true); + if (!ret) + hndl->enabled = true; + } + + return ret; +} + +static int scmi_disable_events(struct scmi_event_handler *hndl) +{ + int ret = 0; + + if (hndl->enabled) { + ret = __scmi_enable_evt(hndl->r_evt, + KEY_XTRACT_SRC_ID(hndl->key), false); + if (!ret) + hndl->enabled = false; + } + + return ret; +} + +/** + * scmi_put_handler_unlocked() - Put an event handler + * @ni: A reference to the notification instance to use + * @hndl: The event handler to act upon + * + * After having got exclusive access to the registered handlers hashtable, + * update the refcount and if @hndl is no more in use by anyone: + * * ask for events' generation disabling + * * unregister and free the handler itself + * + * Context: Assumes all the proper locking has been managed by the caller. + */ +static void scmi_put_handler_unlocked(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + if (refcount_dec_and_test(&hndl->users)) { + if (!IS_HNDL_PENDING(hndl)) + scmi_disable_events(hndl); + scmi_free_event_handler(hndl); + } +} + +static void scmi_put_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_event *r_evt = hndl->r_evt; + + mutex_lock(&ni->pending_mtx); + if (r_evt) + mutex_lock(&r_evt->proto->registered_mtx); + + scmi_put_handler_unlocked(ni, hndl); + + if (r_evt) + mutex_unlock(&r_evt->proto->registered_mtx); + mutex_unlock(&ni->pending_mtx); +} + +/** + * scmi_event_handler_enable_events() - Enable events associated to an handler + * @hndl: The Event handler to act upon + * + * Return: 0 on Success + */ +static int scmi_event_handler_enable_events(struct scmi_event_handler *hndl) +{ + if (scmi_enable_events(hndl)) { + pr_err("Failed to ENABLE events for key:%X !\n", hndl->key); + return -EINVAL; + } + + return 0; +} + +/** + * scmi_register_notifier() - Register a notifier_block for an event + * @handle: The handle identifying the platform instance against which the + * callback is registered + * @proto_id: Protocol ID + * @evt_id: Event ID + * @src_id: Source ID, when NULL register for events coming form ALL possible + * sources + * @nb: A standard notifier block to register for the specified event + * + * Generic helper to register a notifier_block against a protocol event. + * + * A notifier_block @nb will be registered for each distinct event identified + * by the tuple (proto_id, evt_id, src_id) on a dedicated notification chain + * so that: + * + * (proto_X, evt_Y, src_Z) --> chain_X_Y_Z + * + * @src_id meaning is protocol specific and identifies the origin of the event + * (like domain_id, sensor_id and so forth). + * + * @src_id can be NULL to signify that the caller is interested in receiving + * notifications from ALL the available sources for that protocol OR simply that + * the protocol does not support distinct sources. + * + * As soon as one user for the specified tuple appears, an handler is created, + * and that specific event's generation is enabled at the platform level, unless + * an associated registered event is found missing, meaning that the needed + * protocol is still to be initialized and the handler has just been registered + * as still pending. + * + * Return: 0 on Success + */ +static int scmi_register_notifier(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb) +{ + int ret = 0; + u32 evt_key; + struct scmi_event_handler *hndl; + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return -ENODEV; + ni = handle->notify_priv; + + evt_key = MAKE_HASH_KEY(proto_id, evt_id, + src_id ? *src_id : SRC_ID_MASK); + hndl = scmi_get_or_create_handler(ni, evt_key); + if (!hndl) + return -EINVAL; + + blocking_notifier_chain_register(&hndl->chain, nb); + + /* Enable events for not pending handlers */ + if (!IS_HNDL_PENDING(hndl)) { + ret = scmi_event_handler_enable_events(hndl); + if (ret) + scmi_put_handler(ni, hndl); + } + + return ret; +} + +/** + * scmi_unregister_notifier() - Unregister a notifier_block for an event + * @handle: The handle identifying the platform instance against which the + * callback is unregistered + * @proto_id: Protocol ID + * @evt_id: Event ID + * @src_id: Source ID + * @nb: The notifier_block to unregister + * + * Takes care to unregister the provided @nb from the notification chain + * associated to the specified event and, if there are no more users for the + * event handler, frees also the associated event handler structures. + * (this could possibly cause disabling of event's generation at platform level) + * + * Return: 0 on Success + */ +static int scmi_unregister_notifier(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb) +{ + u32 evt_key; + struct scmi_event_handler *hndl; + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return -ENODEV; + ni = handle->notify_priv; + + evt_key = MAKE_HASH_KEY(proto_id, evt_id, + src_id ? *src_id : SRC_ID_MASK); + hndl = scmi_get_handler(ni, evt_key); + if (!hndl) + return -EINVAL; + + /* + * Note that this chain unregistration call is safe on its own + * being internally protected by an rwsem. + */ + blocking_notifier_chain_unregister(&hndl->chain, nb); + scmi_put_handler(ni, hndl); + + /* + * This balances the initial get issued in @scmi_register_notifier. + * If this notifier_block happened to be the last known user callback + * for this event, the handler is here freed and the event's generation + * stopped. + * + * Note that, an ongoing concurrent lookup on the delivery workqueue + * path could still hold the refcount to 1 even after this routine + * completes: in such a case it will be the final put on the delivery + * path which will finally free this unused handler. + */ + scmi_put_handler(ni, hndl); + + return 0; +} + +/** + * scmi_protocols_late_init() - Worker for late initialization + * @work: The work item to use associated to the proper SCMI instance + * + * This kicks in whenever a new protocol has completed its own registration via + * scmi_register_protocol_events(): it is in charge of scanning the table of + * pending handlers (registered by users while the related protocol was still + * not initialized) and finalizing their initialization whenever possible; + * invalid pending handlers are purged at this point in time. + */ +static void scmi_protocols_late_init(struct work_struct *work) +{ + int bkt; + struct scmi_event_handler *hndl; + struct scmi_notify_instance *ni; + struct hlist_node *tmp; + + ni = container_of(work, struct scmi_notify_instance, init_work); + + /* Ensure protocols and events are up to date */ + smp_rmb(); + + mutex_lock(&ni->pending_mtx); + hash_for_each_safe(ni->pending_events_handlers, bkt, tmp, hndl, hash) { + int ret; + + ret = scmi_bind_event_handler(ni, hndl); + if (!ret) { + dev_dbg(ni->handle->dev, + "finalized PENDING handler - key:%X\n", + hndl->key); + ret = scmi_event_handler_enable_events(hndl); + } else { + ret = scmi_valid_pending_handler(ni, hndl); + } + if (ret) { + dev_dbg(ni->handle->dev, + "purging PENDING handler - key:%X\n", + hndl->key); + /* this hndl can be only a pending one */ + scmi_put_handler_unlocked(ni, hndl); + } + } + mutex_unlock(&ni->pending_mtx); +} + +/* + * notify_ops are attached to the handle so that can be accessed + * directly from an scmi_driver to register its own notifiers. + */ +static struct scmi_notify_ops notify_ops = { + .register_event_notifier = scmi_register_notifier, + .unregister_event_notifier = scmi_unregister_notifier, +}; + /** * scmi_notification_init() - Initializes Notification Core Support * @handle: The handle identifying the platform instance to initialize @@ -406,6 +1126,12 @@ int scmi_notification_init(struct scmi_handle *handle) if (!ni->registered_protocols) goto err; + mutex_init(&ni->pending_mtx); + hash_init(ni->pending_events_handlers); + + INIT_WORK(&ni->init_work, scmi_protocols_late_init); + + handle->notify_ops = ¬ify_ops; handle->notify_priv = ni; /* Ensure handle is up to date */ smp_wmb(); diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 9a34b02a9cce..26957d6872a5 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -9,6 +9,7 @@ #define _LINUX_SCMI_PROTOCOL_H #include +#include #include #define SCMI_MAX_STR_SIZE 16 @@ -213,6 +214,49 @@ struct scmi_reset_ops { int (*deassert)(const struct scmi_handle *handle, u32 domain); }; +/** + * struct scmi_notify_ops - represents notifications' operations provided by + * SCMI core + * @register_event_notifier: Register a notifier_block for the requested event + * @unregister_event_notifier: Unregister a notifier_block for the requested + * event + * + * A user can register/unregister its own notifier_block against the wanted + * platform instance regarding the desired event identified by the + * tuple: (proto_id, evt_id, src_id) using the provided register/unregister + * interface where: + * + * @handle: The handle identifying the platform instance to use + * @proto_id: The protocol ID as in SCMI Specification + * @evt_id: The message ID of the desired event as in SCMI Specification + * @src_id: A pointer to the desired source ID if different sources are + * possible for the protocol (like domain_id, sensor_id...etc) + * + * @src_id can be provided as NULL if it simply does NOT make sense for + * the protocol at hand, OR if the user is explicitly interested in + * receiving notifications from ANY existent source associated to the + * specified proto_id / evt_id. + * + * Received notifications are finally delivered to the registered users, + * invoking the callback provided with the notifier_block *nb as follows: + * + * int user_cb(nb, evt_id, report) + * + * with: + * + * @nb: The notifier block provided by the user + * @evt_id: The message ID of the delivered event + * @report: A custom struct describing the specific event delivered + */ +struct scmi_notify_ops { + int (*register_event_notifier)(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb); + int (*unregister_event_notifier)(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb); +}; + /** * struct scmi_handle - Handle returned to ARM SCMI clients for usage. * @@ -223,6 +267,7 @@ struct scmi_reset_ops { * @clk_ops: pointer to set of clock protocol operations * @sensor_ops: pointer to set of sensor protocol operations * @reset_ops: pointer to set of reset protocol operations + * @notify_ops: pointer to set of notifications related operations * @perf_priv: pointer to private data structure specific to performance * protocol(for internal use only) * @clk_priv: pointer to private data structure specific to clock @@ -244,6 +289,7 @@ struct scmi_handle { struct scmi_power_ops *power_ops; struct scmi_sensor_ops *sensor_ops; struct scmi_reset_ops *reset_ops; + struct scmi_notify_ops *notify_ops; /* for protocol internal use */ void *perf_priv; void *clk_priv; From bd31b249692e256ab92e1a4339e42af0e4971738 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:42 +0100 Subject: [PATCH 08/20] firmware: arm_scmi: Add notification dispatch and delivery Add the core SCMI notifications dispatch and delivery support logic which is able to dispatch well-known received events from the Rx interrupt handler to the dedicated deferred worker. From there, it will deliver the events to the registered users' callbacks. Dispatch and delivery support is just added here, still not enabled. Link: https://lore.kernel.org/r/20200701155348.52864-4-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/notify.c | 367 ++++++++++++++++++++++++++++- drivers/firmware/arm_scmi/notify.h | 10 + 2 files changed, 373 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c index 79615eef0148..c4d006cfde88 100644 --- a/drivers/firmware/arm_scmi/notify.c +++ b/drivers/firmware/arm_scmi/notify.c @@ -47,6 +47,27 @@ * as described in the SCMI Protocol specification, while src_id represents an * optional, protocol dependent, source identifier (like domain_id, perf_id * or sensor_id and so forth). + * + * Upon reception of a notification message from the platform the SCMI RX ISR + * passes the received message payload and some ancillary information (including + * an arrival timestamp in nanoseconds) to the core via @scmi_notify() which + * pushes the event-data itself on a protocol-dedicated kfifo queue for further + * deferred processing as specified in @scmi_events_dispatcher(). + * + * Each protocol has it own dedicated work_struct and worker which, once kicked + * by the ISR, takes care to empty its own dedicated queue, deliverying the + * queued items into the proper notification-chain: notifications processing can + * proceed concurrently on distinct workers only between events belonging to + * different protocols while delivery of events within the same protocol is + * still strictly sequentially ordered by time of arrival. + * + * Events' information is then extracted from the SCMI Notification messages and + * conveyed, converted into a custom per-event report struct, as the void *data + * param to the user callback provided by the registered notifier_block, so that + * from the user perspective his callback will look invoked like: + * + * int user_cb(struct notifier_block *nb, unsigned long event_id, void *report) + * */ #define dev_fmt(fmt) "SCMI Notifications - " fmt @@ -67,6 +88,7 @@ #include #include #include +#include #include "notify.h" @@ -164,6 +186,13 @@ #define REVT_NOTIFY_DISABLE(revt, eid, sid) \ REVT_NOTIFY_SET_STATUS((revt), (eid), (sid), false) +#define REVT_FILL_REPORT(revt, ...) \ +({ \ + typeof(revt) r = revt; \ + r->proto->ops->fill_custom_report(r->proto->ni->handle, \ + __VA_ARGS__); \ +}) + #define SCMI_PENDING_HASH_SZ 4 #define SCMI_REGISTERED_HASH_SZ 6 @@ -175,6 +204,7 @@ struct scmi_registered_events_desc; * @gid: GroupID used for devres * @handle: A reference to the platform instance * @init_work: A work item to perform final initializations of pending handlers + * @notify_wq: A reference to the allocated Kernel cmwq * @pending_mtx: A mutex to protect @pending_events_handlers * @registered_protocols: A statically allocated array containing pointers to * all the registered protocol-level specific information @@ -189,6 +219,7 @@ struct scmi_notify_instance { void *gid; struct scmi_handle *handle; struct work_struct init_work; + struct workqueue_struct *notify_wq; /* lock to protect pending_events_handlers */ struct mutex pending_mtx; struct scmi_registered_events_desc **registered_protocols; @@ -199,12 +230,16 @@ struct scmi_notify_instance { * struct events_queue - Describes a queue and its associated worker * @sz: Size in bytes of the related kfifo * @kfifo: A dedicated Kernel kfifo descriptor + * @notify_work: A custom work item bound to this queue + * @wq: A reference to the associated workqueue * * Each protocol has its own dedicated events_queue descriptor. */ struct events_queue { - size_t sz; - struct kfifo kfifo; + size_t sz; + struct kfifo kfifo; + struct work_struct notify_work; + struct workqueue_struct *wq; }; /** @@ -328,9 +363,270 @@ struct scmi_event_handler { #define IS_HNDL_PENDING(hndl) (!(hndl)->r_evt) +static struct scmi_event_handler * +scmi_get_active_handler(struct scmi_notify_instance *ni, u32 evt_key); +static void scmi_put_active_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl); static void scmi_put_handler_unlocked(struct scmi_notify_instance *ni, struct scmi_event_handler *hndl); +/** + * scmi_lookup_and_call_event_chain() - Lookup the proper chain and call it + * @ni: A reference to the notification instance to use + * @evt_key: The key to use to lookup the related notification chain + * @report: The customized event-specific report to pass down to the callbacks + * as their *data parameter. + */ +static inline void +scmi_lookup_and_call_event_chain(struct scmi_notify_instance *ni, + u32 evt_key, void *report) +{ + int ret; + struct scmi_event_handler *hndl; + + /* + * Here ensure the event handler cannot vanish while using it. + * It is legitimate, though, for an handler not to be found at all here, + * e.g. when it has been unregistered by the user after some events had + * already been queued. + */ + hndl = scmi_get_active_handler(ni, evt_key); + if (!hndl) + return; + + ret = blocking_notifier_call_chain(&hndl->chain, + KEY_XTRACT_EVT_ID(evt_key), + report); + /* Notifiers are NOT supposed to cut the chain ... */ + WARN_ON_ONCE(ret & NOTIFY_STOP_MASK); + + scmi_put_active_handler(ni, hndl); +} + +/** + * scmi_process_event_header() - Dequeue and process an event header + * @eq: The queue to use + * @pd: The protocol descriptor to use + * + * Read an event header from the protocol queue into the dedicated scratch + * buffer and looks for a matching registered event; in case an anomalously + * sized read is detected just flush the queue. + * + * Return: + * * a reference to the matching registered event when found + * * ERR_PTR(-EINVAL) when NO registered event could be found + * * NULL when the queue is empty + */ +static inline struct scmi_registered_event * +scmi_process_event_header(struct events_queue *eq, + struct scmi_registered_events_desc *pd) +{ + unsigned int outs; + struct scmi_registered_event *r_evt; + + outs = kfifo_out(&eq->kfifo, pd->eh, + sizeof(struct scmi_event_header)); + if (!outs) + return NULL; + if (outs != sizeof(struct scmi_event_header)) { + dev_err(pd->ni->handle->dev, "corrupted EVT header. Flush.\n"); + kfifo_reset_out(&eq->kfifo); + return NULL; + } + + r_evt = SCMI_GET_REVT_FROM_PD(pd, pd->eh->evt_id); + if (!r_evt) + r_evt = ERR_PTR(-EINVAL); + + return r_evt; +} + +/** + * scmi_process_event_payload() - Dequeue and process an event payload + * @eq: The queue to use + * @pd: The protocol descriptor to use + * @r_evt: The registered event descriptor to use + * + * Read an event payload from the protocol queue into the dedicated scratch + * buffer, fills a custom report and then look for matching event handlers and + * call them; skip any unknown event (as marked by scmi_process_event_header()) + * and in case an anomalously sized read is detected just flush the queue. + * + * Return: False when the queue is empty + */ +static inline bool +scmi_process_event_payload(struct events_queue *eq, + struct scmi_registered_events_desc *pd, + struct scmi_registered_event *r_evt) +{ + u32 src_id, key; + unsigned int outs; + void *report = NULL; + + outs = kfifo_out(&eq->kfifo, pd->eh->payld, pd->eh->payld_sz); + if (!outs) + return false; + + /* Any in-flight event has now been officially processed */ + pd->in_flight = NULL; + + if (outs != pd->eh->payld_sz) { + dev_err(pd->ni->handle->dev, "corrupted EVT Payload. Flush.\n"); + kfifo_reset_out(&eq->kfifo); + return false; + } + + if (IS_ERR(r_evt)) { + dev_warn(pd->ni->handle->dev, + "SKIP UNKNOWN EVT - proto:%X evt:%d\n", + pd->id, pd->eh->evt_id); + return true; + } + + report = REVT_FILL_REPORT(r_evt, pd->eh->evt_id, pd->eh->timestamp, + pd->eh->payld, pd->eh->payld_sz, + r_evt->report, &src_id); + if (!report) { + dev_err(pd->ni->handle->dev, + "report not available - proto:%X evt:%d\n", + pd->id, pd->eh->evt_id); + return true; + } + + /* At first search for a generic ALL src_ids handler... */ + key = MAKE_ALL_SRCS_KEY(pd->id, pd->eh->evt_id); + scmi_lookup_and_call_event_chain(pd->ni, key, report); + + /* ...then search for any specific src_id */ + key = MAKE_HASH_KEY(pd->id, pd->eh->evt_id, src_id); + scmi_lookup_and_call_event_chain(pd->ni, key, report); + + return true; +} + +/** + * scmi_events_dispatcher() - Common worker logic for all work items. + * @work: The work item to use, which is associated to a dedicated events_queue + * + * Logic: + * 1. dequeue one pending RX notification (queued in SCMI RX ISR context) + * 2. generate a custom event report from the received event message + * 3. lookup for any registered ALL_SRC_IDs handler: + * - > call the related notification chain passing in the report + * 4. lookup for any registered specific SRC_ID handler: + * - > call the related notification chain passing in the report + * + * Note that: + * * a dedicated per-protocol kfifo queue is used: in this way an anomalous + * flood of events cannot saturate other protocols' queues. + * * each per-protocol queue is associated to a distinct work_item, which + * means, in turn, that: + * + all protocols can process their dedicated queues concurrently + * (since notify_wq:max_active != 1) + * + anyway at most one worker instance is allowed to run on the same queue + * concurrently: this ensures that we can have only one concurrent + * reader/writer on the associated kfifo, so that we can use it lock-less + * + * Context: Process context. + */ +static void scmi_events_dispatcher(struct work_struct *work) +{ + struct events_queue *eq; + struct scmi_registered_events_desc *pd; + struct scmi_registered_event *r_evt; + + eq = container_of(work, struct events_queue, notify_work); + pd = container_of(eq, struct scmi_registered_events_desc, equeue); + /* + * In order to keep the queue lock-less and the number of memcopies + * to the bare minimum needed, the dispatcher accounts for the + * possibility of per-protocol in-flight events: i.e. an event whose + * reception could end up being split across two subsequent runs of this + * worker, first the header, then the payload. + */ + do { + if (!pd->in_flight) { + r_evt = scmi_process_event_header(eq, pd); + if (!r_evt) + break; + pd->in_flight = r_evt; + } else { + r_evt = pd->in_flight; + } + } while (scmi_process_event_payload(eq, pd, r_evt)); +} + +/** + * scmi_notify() - Queues a notification for further deferred processing + * @handle: The handle identifying the platform instance from which the + * dispatched event is generated + * @proto_id: Protocol ID + * @evt_id: Event ID (msgID) + * @buf: Event Message Payload (without the header) + * @len: Event Message Payload size + * @ts: RX Timestamp in nanoseconds (boottime) + * + * Context: Called in interrupt context to queue a received event for + * deferred processing. + * + * Return: 0 on Success + */ +int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, + const void *buf, size_t len, u64 ts) +{ + struct scmi_registered_event *r_evt; + struct scmi_event_header eh; + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return 0; + ni = handle->notify_priv; + + r_evt = SCMI_GET_REVT(ni, proto_id, evt_id); + if (!r_evt) + return -EINVAL; + + if (len > r_evt->evt->max_payld_sz) { + dev_err(handle->dev, "discard badly sized message\n"); + return -EINVAL; + } + if (kfifo_avail(&r_evt->proto->equeue.kfifo) < sizeof(eh) + len) { + dev_warn(handle->dev, + "queue full, dropping proto_id:%d evt_id:%d ts:%lld\n", + proto_id, evt_id, ts); + return -ENOMEM; + } + + eh.timestamp = ts; + eh.evt_id = evt_id; + eh.payld_sz = len; + /* + * Header and payload are enqueued with two distinct kfifo_in() (so non + * atomic), but this situation is handled properly on the consumer side + * with in-flight events tracking. + */ + kfifo_in(&r_evt->proto->equeue.kfifo, &eh, sizeof(eh)); + kfifo_in(&r_evt->proto->equeue.kfifo, buf, len); + /* + * Don't care about return value here since we just want to ensure that + * a work is queued all the times whenever some items have been pushed + * on the kfifo: + * - if work was already queued it will simply fail to queue a new one + * since it is not needed + * - if work was not queued already it will be now, even in case work + * was in fact already running: this behavior avoids any possible race + * when this function pushes new items onto the kfifos after the + * related executing worker had already determined the kfifo to be + * empty and it was terminating. + */ + queue_work(r_evt->proto->equeue.wq, + &r_evt->proto->equeue.notify_work); + + return 0; +} + /** * scmi_kfifo_free() - Devres action helper to free the kfifo * @kfifo: The kfifo to free @@ -353,13 +649,22 @@ static void scmi_kfifo_free(void *kfifo) static int scmi_initialize_events_queue(struct scmi_notify_instance *ni, struct events_queue *equeue, size_t sz) { + int ret; + if (kfifo_alloc(&equeue->kfifo, sz, GFP_KERNEL)) return -ENOMEM; /* Size could have been roundup to power-of-two */ equeue->sz = kfifo_size(&equeue->kfifo); - return devm_add_action_or_reset(ni->handle->dev, scmi_kfifo_free, - &equeue->kfifo); + ret = devm_add_action_or_reset(ni->handle->dev, scmi_kfifo_free, + &equeue->kfifo); + if (ret) + return ret; + + INIT_WORK(&equeue->notify_work, scmi_events_dispatcher); + equeue->wq = ni->notify_wq; + + return ret; } /** @@ -758,6 +1063,37 @@ scmi_get_or_create_handler(struct scmi_notify_instance *ni, u32 evt_key) return __scmi_event_handler_get_ops(ni, evt_key, true); } +/** + * scmi_get_active_handler() - Helper to get active handlers only + * @ni: A reference to the notification instance to use + * @evt_key: The event key to use + * + * Search for the desired handler matching the key only in the per-protocol + * table of registered handlers: this is called only from the dispatching path + * so want to be as quick as possible and do not care about pending. + * + * Return: A properly refcounted active handler + */ +static struct scmi_event_handler * +scmi_get_active_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + struct scmi_registered_event *r_evt; + struct scmi_event_handler *hndl = NULL; + + r_evt = SCMI_GET_REVT(ni, KEY_XTRACT_PROTO_ID(evt_key), + KEY_XTRACT_EVT_ID(evt_key)); + if (r_evt) { + mutex_lock(&r_evt->proto->registered_mtx); + hndl = KEY_FIND(r_evt->proto->registered_events_handlers, + hndl, evt_key); + if (hndl) + refcount_inc(&hndl->users); + mutex_unlock(&r_evt->proto->registered_mtx); + } + + return hndl; +} + /** * __scmi_enable_evt() - Enable/disable events generation * @r_evt: The registered event to act upon @@ -883,6 +1219,16 @@ static void scmi_put_handler(struct scmi_notify_instance *ni, mutex_unlock(&ni->pending_mtx); } +static void scmi_put_active_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_event *r_evt = hndl->r_evt; + + mutex_lock(&r_evt->proto->registered_mtx); + scmi_put_handler_unlocked(ni, hndl); + mutex_unlock(&r_evt->proto->registered_mtx); +} + /** * scmi_event_handler_enable_events() - Enable events associated to an handler * @hndl: The Event handler to act upon @@ -1121,6 +1467,12 @@ int scmi_notification_init(struct scmi_handle *handle) ni->gid = gid; ni->handle = handle; + ni->notify_wq = alloc_workqueue("scmi_notify", + WQ_UNBOUND | WQ_FREEZABLE | WQ_SYSFS, + 0); + if (!ni->notify_wq) + goto err; + ni->registered_protocols = devm_kcalloc(handle->dev, SCMI_MAX_PROTO, sizeof(char *), GFP_KERNEL); if (!ni->registered_protocols) @@ -1162,5 +1514,12 @@ void scmi_notification_exit(struct scmi_handle *handle) return; ni = handle->notify_priv; + handle->notify_priv = NULL; + /* Ensure handle is up to date */ + smp_wmb(); + + /* Destroy while letting pending work complete */ + destroy_workqueue(ni->notify_wq); + devres_release_group(ni->handle->dev, ni->gid); } diff --git a/drivers/firmware/arm_scmi/notify.h b/drivers/firmware/arm_scmi/notify.h index 48702e42995f..3791bb7aa79b 100644 --- a/drivers/firmware/arm_scmi/notify.h +++ b/drivers/firmware/arm_scmi/notify.h @@ -35,6 +35,11 @@ struct scmi_event { * @set_notify_enabled: Enable/disable the required evt_id/src_id notifications * using the proper custom protocol commands. * Return 0 on Success + * @fill_custom_report: fills a custom event report from the provided + * event message payld identifying the event + * specific src_id. + * Return NULL on failure otherwise @report now fully + * populated * * Context: Helpers described in &struct scmi_event_ops are called only in * process context. @@ -42,6 +47,9 @@ struct scmi_event { struct scmi_event_ops { int (*set_notify_enabled)(const struct scmi_handle *handle, u8 evt_id, u32 src_id, bool enabled); + void *(*fill_custom_report)(const struct scmi_handle *handle, + u8 evt_id, u64 timestamp, const void *payld, + size_t payld_sz, void *report, u32 *src_id); }; int scmi_notification_init(struct scmi_handle *handle); @@ -52,5 +60,7 @@ int scmi_register_protocol_events(const struct scmi_handle *handle, const struct scmi_event_ops *ops, const struct scmi_event *evt, int num_events, int num_sources); +int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, + const void *buf, size_t len, u64 ts); #endif /* _SCMI_NOTIFY_H */ From 6b8a69131dc63df2eab3fc6f5f91b60bdd5301ff Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:43 +0100 Subject: [PATCH 09/20] firmware: arm_scmi: Enable notification core Initialize and enable SCMI notifications core support during bus/driver probe phase, so that protocols can start registering their supported events during their initialization. Link: https://lore.kernel.org/r/20200701155348.52864-5-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/driver.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index a36a10b7b9d6..19a4287fc0f7 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -26,6 +26,7 @@ #include #include "common.h" +#include "notify.h" #define CREATE_TRACE_POINTS #include @@ -204,11 +205,13 @@ __scmi_xfer_put(struct scmi_xfers_info *minfo, struct scmi_xfer *xfer) static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr) { + u64 ts; struct scmi_xfer *xfer; struct device *dev = cinfo->dev; struct scmi_info *info = handle_to_scmi_info(cinfo->handle); struct scmi_xfers_info *minfo = &info->rx_minfo; + ts = ktime_get_boottime_ns(); xfer = scmi_xfer_get(cinfo->handle, minfo); if (IS_ERR(xfer)) { dev_err(dev, "failed to get free message slot (%ld)\n", @@ -221,6 +224,8 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr) scmi_dump_header_dbg(dev, &xfer->hdr); info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size, xfer); + scmi_notify(cinfo->handle, xfer->hdr.protocol_id, + xfer->hdr.id, xfer->rx.buf, xfer->rx.len, ts); trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, xfer->hdr.protocol_id, xfer->hdr.seq, @@ -788,6 +793,9 @@ static int scmi_probe(struct platform_device *pdev) if (ret) return ret; + if (scmi_notification_init(handle)) + dev_err(dev, "SCMI Notifications NOT available.\n"); + ret = scmi_base_protocol_init(handle); if (ret) { dev_err(dev, "unable to communicate with SCMI(%d)\n", ret); @@ -830,6 +838,8 @@ static int scmi_remove(struct platform_device *pdev) struct scmi_info *info = platform_get_drvdata(pdev); struct idr *idr = &info->tx_idr; + scmi_notification_exit(&info->handle); + mutex_lock(&scmi_list_mutex); if (info->users) ret = -EBUSY; From e27077bc04d5a2e09a0860ca086e1d55adf6a16d Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:44 +0100 Subject: [PATCH 10/20] firmware: arm_scmi: Add power notifications support Make SCMI power protocol register with the notification core. Link: https://lore.kernel.org/r/20200701155348.52864-6-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/power.c | 92 +++++++++++++++++++++++++++++-- include/linux/scmi_protocol.h | 12 ++++ 2 files changed, 98 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/arm_scmi/power.c b/drivers/firmware/arm_scmi/power.c index cf7f0312381b..4f6757980739 100644 --- a/drivers/firmware/arm_scmi/power.c +++ b/drivers/firmware/arm_scmi/power.c @@ -5,19 +5,18 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications POWER - " fmt + +#include + #include "common.h" +#include "notify.h" enum scmi_power_protocol_cmd { POWER_DOMAIN_ATTRIBUTES = 0x3, POWER_STATE_SET = 0x4, POWER_STATE_GET = 0x5, POWER_STATE_NOTIFY = 0x6, - POWER_STATE_CHANGE_REQUESTED_NOTIFY = 0x7, -}; - -enum scmi_power_protocol_notify { - POWER_STATE_CHANGED = 0x0, - POWER_STATE_CHANGE_REQUESTED = 0x1, }; struct scmi_msg_resp_power_attributes { @@ -48,6 +47,12 @@ struct scmi_power_state_notify { __le32 notify_enable; }; +struct scmi_power_state_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 power_state; +}; + struct power_dom_info { bool state_set_sync; bool state_set_async; @@ -186,6 +191,75 @@ static struct scmi_power_ops power_ops = { .state_get = scmi_power_state_get, }; +static int scmi_power_request_notify(const struct scmi_handle *handle, + u32 domain, bool enable) +{ + int ret; + struct scmi_xfer *t; + struct scmi_power_state_notify *notify; + + ret = scmi_xfer_get_init(handle, POWER_STATE_NOTIFY, + SCMI_PROTOCOL_POWER, sizeof(*notify), 0, &t); + if (ret) + return ret; + + notify = t->tx.buf; + notify->domain = cpu_to_le32(domain); + notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0; + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + +static int scmi_power_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_power_request_notify(handle, src_id, enable); + if (ret) + pr_debug("FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_power_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, u64 timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + const struct scmi_power_state_notify_payld *p = payld; + struct scmi_power_state_changed_report *r = report; + + if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED || sizeof(*p) != payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->power_state = le32_to_cpu(p->power_state); + *src_id = r->domain_id; + + return r; +} + +static const struct scmi_event power_events[] = { + { + .id = SCMI_EVENT_POWER_STATE_CHANGED, + .max_payld_sz = sizeof(struct scmi_power_state_notify_payld), + .max_report_sz = + sizeof(struct scmi_power_state_changed_report), + }, +}; + +static const struct scmi_event_ops power_event_ops = { + .set_notify_enabled = scmi_power_set_notify_enabled, + .fill_custom_report = scmi_power_fill_custom_report, +}; + static int scmi_power_protocol_init(struct scmi_handle *handle) { int domain; @@ -214,6 +288,12 @@ static int scmi_power_protocol_init(struct scmi_handle *handle) scmi_power_domain_attributes_get(handle, domain, dom); } + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_POWER, SCMI_PROTO_QUEUE_SZ, + &power_event_ops, power_events, + ARRAY_SIZE(power_events), + pinfo->num_domains); + pinfo->version = version; handle->power_ops = &power_ops; handle->power_priv = pinfo; diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 26957d6872a5..81dc3b132fda 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -375,4 +375,16 @@ typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *); int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn); void scmi_protocol_unregister(int protocol_id); +/* SCMI Notification API - Custom Event Reports */ +enum scmi_notification_events { + SCMI_EVENT_POWER_STATE_CHANGED = 0x0, +}; + +struct scmi_power_state_changed_report { + u64 timestamp; + u32 agent_id; + u32 domain_id; + u32 power_state; +}; + #endif /* _LINUX_SCMI_PROTOCOL_H */ From fb5086dc4746184a9325fc25411226a750fb252c Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:45 +0100 Subject: [PATCH 11/20] firmware: arm_scmi: Add perf notifications support Make SCMI perf protocol register with the notification core. Link: https://lore.kernel.org/r/20200701155348.52864-7-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/perf.c | 139 +++++++++++++++++++++++++++++-- include/linux/scmi_protocol.h | 17 ++++ 2 files changed, 151 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c index 7b8d7cebdac9..8bcad96e06ca 100644 --- a/drivers/firmware/arm_scmi/perf.c +++ b/drivers/firmware/arm_scmi/perf.c @@ -5,15 +5,19 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications PERF - " fmt + #include #include #include #include #include #include +#include #include #include "common.h" +#include "notify.h" enum scmi_performance_protocol_cmd { PERF_DOMAIN_ATTRIBUTES = 0x3, @@ -27,11 +31,6 @@ enum scmi_performance_protocol_cmd { PERF_DESCRIBE_FASTCHANNEL = 0xb, }; -enum scmi_performance_protocol_notify { - PERFORMANCE_LIMITS_CHANGED = 0x0, - PERFORMANCE_LEVEL_CHANGED = 0x1, -}; - struct scmi_opp { u32 perf; u32 power; @@ -86,6 +85,19 @@ struct scmi_perf_notify_level_or_limits { __le32 notify_enable; }; +struct scmi_perf_limits_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 range_max; + __le32 range_min; +}; + +struct scmi_perf_level_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 performance_level; +}; + struct scmi_msg_resp_perf_describe_levels { __le16 num_returned; __le16 num_remaining; @@ -158,6 +170,11 @@ struct scmi_perf_info { struct perf_dom_info *dom_info; }; +static enum scmi_performance_protocol_cmd evt_2_cmd[] = { + PERF_NOTIFY_LIMITS, + PERF_NOTIFY_LEVEL, +}; + static int scmi_perf_attributes_get(const struct scmi_handle *handle, struct scmi_perf_info *pi) { @@ -488,6 +505,29 @@ static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain, return scmi_perf_mb_level_get(handle, domain, level, poll); } +static int scmi_perf_level_limits_notify(const struct scmi_handle *handle, + u32 domain, int message_id, + bool enable) +{ + int ret; + struct scmi_xfer *t; + struct scmi_perf_notify_level_or_limits *notify; + + ret = scmi_xfer_get_init(handle, message_id, SCMI_PROTOCOL_PERF, + sizeof(*notify), 0, &t); + if (ret) + return ret; + + notify = t->tx.buf; + notify->domain = cpu_to_le32(domain); + notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0; + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + static bool scmi_perf_fc_size_is_valid(u32 msg, u32 size) { if ((msg == PERF_LEVEL_GET || msg == PERF_LEVEL_SET) && size == 4) @@ -722,6 +762,89 @@ static struct scmi_perf_ops perf_ops = { .fast_switch_possible = scmi_fast_switch_possible, }; +static int scmi_perf_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret, cmd_id; + + if (evt_id >= ARRAY_SIZE(evt_2_cmd)) + return -EINVAL; + + cmd_id = evt_2_cmd[evt_id]; + ret = scmi_perf_level_limits_notify(handle, src_id, cmd_id, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_perf_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, u64 timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + void *rep = NULL; + + switch (evt_id) { + case SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED: + { + const struct scmi_perf_limits_notify_payld *p = payld; + struct scmi_perf_limits_report *r = report; + + if (sizeof(*p) != payld_sz) + break; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->range_max = le32_to_cpu(p->range_max); + r->range_min = le32_to_cpu(p->range_min); + *src_id = r->domain_id; + rep = r; + break; + } + case SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED: + { + const struct scmi_perf_level_notify_payld *p = payld; + struct scmi_perf_level_report *r = report; + + if (sizeof(*p) != payld_sz) + break; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->performance_level = le32_to_cpu(p->performance_level); + *src_id = r->domain_id; + rep = r; + break; + } + default: + break; + } + + return rep; +} + +static const struct scmi_event perf_events[] = { + { + .id = SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, + .max_payld_sz = sizeof(struct scmi_perf_limits_notify_payld), + .max_report_sz = sizeof(struct scmi_perf_limits_report), + }, + { + .id = SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED, + .max_payld_sz = sizeof(struct scmi_perf_level_notify_payld), + .max_report_sz = sizeof(struct scmi_perf_level_report), + }, +}; + +static const struct scmi_event_ops perf_event_ops = { + .set_notify_enabled = scmi_perf_set_notify_enabled, + .fill_custom_report = scmi_perf_fill_custom_report, +}; + static int scmi_perf_protocol_init(struct scmi_handle *handle) { int domain; @@ -754,6 +877,12 @@ static int scmi_perf_protocol_init(struct scmi_handle *handle) scmi_perf_domain_init_fc(handle, domain, &dom->fc_info); } + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_PERF, SCMI_PROTO_QUEUE_SZ, + &perf_event_ops, perf_events, + ARRAY_SIZE(perf_events), + pinfo->num_domains); + pinfo->version = version; handle->perf_ops = &perf_ops; handle->perf_priv = pinfo; diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 81dc3b132fda..65ad83ddde70 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -378,6 +378,8 @@ void scmi_protocol_unregister(int protocol_id); /* SCMI Notification API - Custom Event Reports */ enum scmi_notification_events { SCMI_EVENT_POWER_STATE_CHANGED = 0x0, + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0, + SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1, }; struct scmi_power_state_changed_report { @@ -387,4 +389,19 @@ struct scmi_power_state_changed_report { u32 power_state; }; +struct scmi_perf_limits_report { + u64 timestamp; + u32 agent_id; + u32 domain_id; + u32 range_max; + u32 range_min; +}; + +struct scmi_perf_level_report { + u64 timestamp; + u32 agent_id; + u32 domain_id; + u32 performance_level; +}; + #endif /* _LINUX_SCMI_PROTOCOL_H */ From 128e3e9311a95bab6b267b7a93eb9ebe2347dbda Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:46 +0100 Subject: [PATCH 12/20] firmware: arm_scmi: Add sensor notifications support Make SCMI sensor protocol register with the notification core. Link: https://lore.kernel.org/r/20200701155348.52864-8-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/sensors.c | 69 ++++++++++++++++++++++++++--- include/linux/scmi_protocol.h | 13 +++--- 2 files changed, 72 insertions(+), 10 deletions(-) diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c index db1b1ab303da..2120ac4787c9 100644 --- a/drivers/firmware/arm_scmi/sensors.c +++ b/drivers/firmware/arm_scmi/sensors.c @@ -5,7 +5,12 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications SENSOR - " fmt + +#include + #include "common.h" +#include "notify.h" enum scmi_sensor_protocol_cmd { SENSOR_DESCRIPTION_GET = 0x3, @@ -14,10 +19,6 @@ enum scmi_sensor_protocol_cmd { SENSOR_READING_GET = 0x6, }; -enum scmi_sensor_protocol_notify { - SENSOR_TRIP_POINT_EVENT = 0x0, -}; - struct scmi_msg_resp_sensor_attributes { __le16 num_sensors; u8 max_requests; @@ -71,6 +72,12 @@ struct scmi_msg_sensor_reading_get { #define SENSOR_READ_ASYNC BIT(0) }; +struct scmi_sensor_trip_notify_payld { + __le32 agent_id; + __le32 sensor_id; + __le32 trip_point_desc; +}; + struct sensors_info { u32 version; int num_sensors; @@ -271,11 +278,57 @@ static int scmi_sensor_count_get(const struct scmi_handle *handle) static struct scmi_sensor_ops sensor_ops = { .count_get = scmi_sensor_count_get, .info_get = scmi_sensor_info_get, - .trip_point_notify = scmi_sensor_trip_point_notify, .trip_point_config = scmi_sensor_trip_point_config, .reading_get = scmi_sensor_reading_get, }; +static int scmi_sensor_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_sensor_trip_point_notify(handle, src_id, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_sensor_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, u64 timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + const struct scmi_sensor_trip_notify_payld *p = payld; + struct scmi_sensor_trip_point_report *r = report; + + if (evt_id != SCMI_EVENT_SENSOR_TRIP_POINT_EVENT || + sizeof(*p) != payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->sensor_id = le32_to_cpu(p->sensor_id); + r->trip_point_desc = le32_to_cpu(p->trip_point_desc); + *src_id = r->sensor_id; + + return r; +} + +static const struct scmi_event sensor_events[] = { + { + .id = SCMI_EVENT_SENSOR_TRIP_POINT_EVENT, + .max_payld_sz = sizeof(struct scmi_sensor_trip_notify_payld), + .max_report_sz = sizeof(struct scmi_sensor_trip_point_report), + }, +}; + +static const struct scmi_event_ops sensor_event_ops = { + .set_notify_enabled = scmi_sensor_set_notify_enabled, + .fill_custom_report = scmi_sensor_fill_custom_report, +}; + static int scmi_sensors_protocol_init(struct scmi_handle *handle) { u32 version; @@ -299,6 +352,12 @@ static int scmi_sensors_protocol_init(struct scmi_handle *handle) scmi_sensor_description_get(handle, sinfo); + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_SENSOR, SCMI_PROTO_QUEUE_SZ, + &sensor_event_ops, sensor_events, + ARRAY_SIZE(sensor_events), + sinfo->num_sensors); + sinfo->version = version; handle->sensor_ops = &sensor_ops; handle->sensor_priv = sinfo; diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 65ad83ddde70..d0ea4a5037e7 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -176,18 +176,13 @@ enum scmi_sensor_class { * * @count_get: get the count of sensors provided by SCMI * @info_get: get the information of the specified sensor - * @trip_point_notify: control notifications on cross-over events for - * the trip-points * @trip_point_config: selects and configures a trip-point of interest * @reading_get: gets the current value of the sensor */ struct scmi_sensor_ops { int (*count_get)(const struct scmi_handle *handle); - const struct scmi_sensor_info *(*info_get) (const struct scmi_handle *handle, u32 sensor_id); - int (*trip_point_notify)(const struct scmi_handle *handle, - u32 sensor_id, bool enable); int (*trip_point_config)(const struct scmi_handle *handle, u32 sensor_id, u8 trip_id, u64 trip_value); int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id, @@ -380,6 +375,7 @@ enum scmi_notification_events { SCMI_EVENT_POWER_STATE_CHANGED = 0x0, SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0, SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1, + SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0, }; struct scmi_power_state_changed_report { @@ -404,4 +400,11 @@ struct scmi_perf_level_report { u32 performance_level; }; +struct scmi_sensor_trip_point_report { + u64 timestamp; + u32 agent_id; + u32 sensor_id; + u32 trip_point_desc; +}; + #endif /* _LINUX_SCMI_PROTOCOL_H */ From 469ca1822d64e4a786935576edb696c52119aa11 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:47 +0100 Subject: [PATCH 13/20] firmware: arm_scmi: Add reset notifications support Make SCMI reset protocol register with the notification core. Link: https://lore.kernel.org/r/20200701155348.52864-9-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/reset.c | 96 +++++++++++++++++++++++++++++-- include/linux/scmi_protocol.h | 8 +++ 2 files changed, 100 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/arm_scmi/reset.c b/drivers/firmware/arm_scmi/reset.c index de73054554f3..fb7cb517900b 100644 --- a/drivers/firmware/arm_scmi/reset.c +++ b/drivers/firmware/arm_scmi/reset.c @@ -5,7 +5,12 @@ * Copyright (C) 2019 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications RESET - " fmt + +#include + #include "common.h" +#include "notify.h" enum scmi_reset_protocol_cmd { RESET_DOMAIN_ATTRIBUTES = 0x3, @@ -13,10 +18,6 @@ enum scmi_reset_protocol_cmd { RESET_NOTIFY = 0x5, }; -enum scmi_reset_protocol_notify { - RESET_ISSUED = 0x0, -}; - #define NUM_RESET_DOMAIN_MASK 0xffff #define RESET_NOTIFY_ENABLE BIT(0) @@ -40,6 +41,18 @@ struct scmi_msg_reset_domain_reset { #define ARCH_COLD_RESET (ARCH_RESET_TYPE | COLD_RESET_STATE) }; +struct scmi_msg_reset_notify { + __le32 id; + __le32 event_control; +#define RESET_TP_NOTIFY_ALL BIT(0) +}; + +struct scmi_reset_issued_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 reset_state; +}; + struct reset_dom_info { bool async_reset; bool reset_notify; @@ -190,6 +203,75 @@ static struct scmi_reset_ops reset_ops = { .deassert = scmi_reset_domain_deassert, }; +static int scmi_reset_notify(const struct scmi_handle *handle, u32 domain_id, + bool enable) +{ + int ret; + u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0; + struct scmi_xfer *t; + struct scmi_msg_reset_notify *cfg; + + ret = scmi_xfer_get_init(handle, RESET_NOTIFY, + SCMI_PROTOCOL_RESET, sizeof(*cfg), 0, &t); + if (ret) + return ret; + + cfg = t->tx.buf; + cfg->id = cpu_to_le32(domain_id); + cfg->event_control = cpu_to_le32(evt_cntl); + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + +static int scmi_reset_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_reset_notify(handle, src_id, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_reset_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, u64 timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + const struct scmi_reset_issued_notify_payld *p = payld; + struct scmi_reset_issued_report *r = report; + + if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->reset_state = le32_to_cpu(p->reset_state); + *src_id = r->domain_id; + + return r; +} + +static const struct scmi_event reset_events[] = { + { + .id = SCMI_EVENT_RESET_ISSUED, + .max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld), + .max_report_sz = sizeof(struct scmi_reset_issued_report), + }, +}; + +static const struct scmi_event_ops reset_event_ops = { + .set_notify_enabled = scmi_reset_set_notify_enabled, + .fill_custom_report = scmi_reset_fill_custom_report, +}; + static int scmi_reset_protocol_init(struct scmi_handle *handle) { int domain; @@ -218,6 +300,12 @@ static int scmi_reset_protocol_init(struct scmi_handle *handle) scmi_reset_domain_attributes_get(handle, domain, dom); } + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_RESET, SCMI_PROTO_QUEUE_SZ, + &reset_event_ops, reset_events, + ARRAY_SIZE(reset_events), + pinfo->num_domains); + pinfo->version = version; handle->reset_ops = &reset_ops; handle->reset_priv = pinfo; diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index d0ea4a5037e7..d04d66be596d 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -376,6 +376,7 @@ enum scmi_notification_events { SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0, SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1, SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0, + SCMI_EVENT_RESET_ISSUED = 0x0, }; struct scmi_power_state_changed_report { @@ -407,4 +408,11 @@ struct scmi_sensor_trip_point_report { u32 trip_point_desc; }; +struct scmi_reset_issued_report { + u64 timestamp; + u32 agent_id; + u32 domain_id; + u32 reset_state; +}; + #endif /* _LINUX_SCMI_PROTOCOL_H */ From 585dfab3fb80e67b3a54790b3d5ef2991feb3950 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Wed, 1 Jul 2020 16:53:48 +0100 Subject: [PATCH 14/20] firmware: arm_scmi: Add base notifications support Make SCMI base protocol register with the notification core. Link: https://lore.kernel.org/r/20200701155348.52864-10-cristian.marussi@arm.com Reviewed-by: Jonathan Cameron Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/base.c | 108 +++++++++++++++++++++++++++++-- include/linux/scmi_protocol.h | 9 +++ 2 files changed, 113 insertions(+), 4 deletions(-) diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c index ce7d9203e41b..54f378e946f1 100644 --- a/drivers/firmware/arm_scmi/base.c +++ b/drivers/firmware/arm_scmi/base.c @@ -5,7 +5,15 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications BASE - " fmt + +#include + #include "common.h" +#include "notify.h" + +#define SCMI_BASE_NUM_SOURCES 1 +#define SCMI_BASE_MAX_CMD_ERR_COUNT 1024 enum scmi_base_protocol_cmd { BASE_DISCOVER_VENDOR = 0x3, @@ -19,16 +27,25 @@ enum scmi_base_protocol_cmd { BASE_RESET_AGENT_CONFIGURATION = 0xb, }; -enum scmi_base_protocol_notify { - BASE_ERROR_EVENT = 0x0, -}; - struct scmi_msg_resp_base_attributes { u8 num_protocols; u8 num_agents; __le16 reserved; }; +struct scmi_msg_base_error_notify { + __le32 event_control; +#define BASE_TP_NOTIFY_ALL BIT(0) +}; + +struct scmi_base_error_notify_payld { + __le32 agent_id; + __le32 error_status; +#define IS_FATAL_ERROR(x) ((x) & BIT(31)) +#define ERROR_CMD_COUNT(x) FIELD_GET(GENMASK(9, 0), (x)) + __le64 msg_reports[SCMI_BASE_MAX_CMD_ERR_COUNT]; +}; + /** * scmi_base_attributes_get() - gets the implementation details * that are associated with the base protocol. @@ -222,6 +239,83 @@ static int scmi_base_discover_agent_get(const struct scmi_handle *handle, return ret; } +static int scmi_base_error_notify(const struct scmi_handle *handle, bool enable) +{ + int ret; + u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0; + struct scmi_xfer *t; + struct scmi_msg_base_error_notify *cfg; + + ret = scmi_xfer_get_init(handle, BASE_NOTIFY_ERRORS, + SCMI_PROTOCOL_BASE, sizeof(*cfg), 0, &t); + if (ret) + return ret; + + cfg = t->tx.buf; + cfg->event_control = cpu_to_le32(evt_cntl); + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + +static int scmi_base_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_base_error_notify(handle, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] ret:%d\n", evt_id, ret); + + return ret; +} + +static void *scmi_base_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, u64 timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + int i; + const struct scmi_base_error_notify_payld *p = payld; + struct scmi_base_error_report *r = report; + + /* + * BaseError notification payload is variable in size but + * up to a maximum length determined by the struct ponted by p. + * Instead payld_sz is the effective length of this notification + * payload so cannot be greater of the maximum allowed size as + * pointed by p. + */ + if (evt_id != SCMI_EVENT_BASE_ERROR_EVENT || sizeof(*p) < payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status)); + r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status)); + for (i = 0; i < r->cmd_count; i++) + r->reports[i] = le64_to_cpu(p->msg_reports[i]); + *src_id = 0; + + return r; +} + +static const struct scmi_event base_events[] = { + { + .id = SCMI_EVENT_BASE_ERROR_EVENT, + .max_payld_sz = sizeof(struct scmi_base_error_notify_payld), + .max_report_sz = sizeof(struct scmi_base_error_report) + + SCMI_BASE_MAX_CMD_ERR_COUNT * sizeof(u64), + }, +}; + +static const struct scmi_event_ops base_event_ops = { + .set_notify_enabled = scmi_base_set_notify_enabled, + .fill_custom_report = scmi_base_fill_custom_report, +}; + int scmi_base_protocol_init(struct scmi_handle *h) { int id, ret; @@ -256,6 +350,12 @@ int scmi_base_protocol_init(struct scmi_handle *h) dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols, rev->num_agents); + scmi_register_protocol_events(handle, SCMI_PROTOCOL_BASE, + (4 * SCMI_PROTO_QUEUE_SZ), + &base_event_ops, base_events, + ARRAY_SIZE(base_events), + SCMI_BASE_NUM_SOURCES); + for (id = 0; id < rev->num_agents; id++) { scmi_base_discover_agent_get(handle, id, name); dev_dbg(dev, "Agent %d: %s\n", id, name); diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index d04d66be596d..46d98be92466 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -377,6 +377,7 @@ enum scmi_notification_events { SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1, SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0, SCMI_EVENT_RESET_ISSUED = 0x0, + SCMI_EVENT_BASE_ERROR_EVENT = 0x0, }; struct scmi_power_state_changed_report { @@ -415,4 +416,12 @@ struct scmi_reset_issued_report { u32 reset_state; }; +struct scmi_base_error_report { + u64 timestamp; + u32 agent_id; + bool fatal; + u16 cmd_count; + u64 reports[0]; +}; + #endif /* _LINUX_SCMI_PROTOCOL_H */ From dccec73de91de04f2a62c877411ecbe368a775f7 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 9 Jul 2020 09:17:04 +0100 Subject: [PATCH 15/20] firmware: arm_scmi: Keep the discrete clock rates sorted Instead of relying on the firmware to keep the clock rates sorted, let us sort the list. This is not essential for clock layer but it helps to find the min and max rates easily from the list. Link: https://lore.kernel.org/r/20200709081705.46084-1-sudeep.holla@arm.com Fixes: 5f6c6430e904 ("firmware: arm_scmi: add initial support for clock protocol") Reported-and-tested-by: Dien Pham Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/clock.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c index 4c2227662b26..6593ce87f420 100644 --- a/drivers/firmware/arm_scmi/clock.c +++ b/drivers/firmware/arm_scmi/clock.c @@ -5,6 +5,8 @@ * Copyright (C) 2018 ARM Ltd. */ +#include + #include "common.h" enum scmi_clock_protocol_cmd { @@ -121,11 +123,23 @@ static int scmi_clock_attributes_get(const struct scmi_handle *handle, return ret; } +static int rate_cmp_func(const void *_r1, const void *_r2) +{ + const u64 *r1 = _r1, *r2 = _r2; + + if (*r1 < *r2) + return -1; + else if (*r1 == *r2) + return 0; + else + return 1; +} + static int scmi_clock_describe_rates_get(const struct scmi_handle *handle, u32 clk_id, struct scmi_clock_info *clk) { - u64 *rate; + u64 *rate = 0; int ret, cnt; bool rate_discrete = false; u32 tot_rate_cnt = 0, rates_flag; @@ -184,8 +198,10 @@ scmi_clock_describe_rates_get(const struct scmi_handle *handle, u32 clk_id, */ } while (num_returned && num_remaining); - if (rate_discrete) + if (rate_discrete && rate) { clk->list.num_rates = tot_rate_cnt; + sort(rate, tot_rate_cnt, sizeof(*rate), rate_cmp_func, NULL); + } clk->rate_discrete = rate_discrete; From fcd2e0deae50bce48450f14c8fc5611b08d7438c Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 9 Jul 2020 09:17:05 +0100 Subject: [PATCH 16/20] clk: scmi: Fix min and max rate when registering clocks with discrete rates Currently we are not initializing the scmi clock with discrete rates correctly. We fetch the min_rate and max_rate value only for clocks with ranges and ignore the ones with discrete rates. This will lead to wrong initialization of rate range when clock supports discrete rate. Fix this by using the first and the last rate in the sorted list of the discrete clock rates while registering the clock. Link: https://lore.kernel.org/r/20200709081705.46084-2-sudeep.holla@arm.com Fixes: 6d6a1d82eaef7 ("clk: add support for clocks provided by SCMI") Reviewed-by: Stephen Boyd Reported-and-tested-by: Dien Pham Signed-off-by: Sudeep Holla --- drivers/clk/clk-scmi.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c index c491f5de0f3f..c754dfbb73fd 100644 --- a/drivers/clk/clk-scmi.c +++ b/drivers/clk/clk-scmi.c @@ -103,6 +103,8 @@ static const struct clk_ops scmi_clk_ops = { static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk) { int ret; + unsigned long min_rate, max_rate; + struct clk_init_data init = { .flags = CLK_GET_RATE_NOCACHE, .num_parents = 0, @@ -112,9 +114,23 @@ static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk) sclk->hw.init = &init; ret = devm_clk_hw_register(dev, &sclk->hw); - if (!ret) - clk_hw_set_rate_range(&sclk->hw, sclk->info->range.min_rate, - sclk->info->range.max_rate); + if (ret) + return ret; + + if (sclk->info->rate_discrete) { + int num_rates = sclk->info->list.num_rates; + + if (num_rates <= 0) + return -EINVAL; + + min_rate = sclk->info->list.rates[0]; + max_rate = sclk->info->list.rates[num_rates - 1]; + } else { + min_rate = sclk->info->range.min_rate; + max_rate = sclk->info->range.max_rate; + } + + clk_hw_set_rate_range(&sclk->hw, min_rate, max_rate); return ret; } From a4ee9d0194c24509333caaeba894ca017e5942c8 Mon Sep 17 00:00:00 2001 From: Sudeep Holla Date: Thu, 9 Jul 2020 16:31:55 +0100 Subject: [PATCH 17/20] firmware: arm_scmi: Provide a missing function param description gcc as well as clang now produce warnings for missing kerneldoc function parameter. Fix the following W=1 kernel build warning: drivers/firmware/arm_scmi/smc.c:32: warning: Function parameter or member 'shmem_lock' not described in 'scmi_smc' Link: https://lore.kernel.org/r/20200709153155.22573-1-sudeep.holla@arm.com Reported-by: kbuild test robot Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/smc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c index 49bc4b0e8428..a1537d123e38 100644 --- a/drivers/firmware/arm_scmi/smc.c +++ b/drivers/firmware/arm_scmi/smc.c @@ -21,6 +21,7 @@ * * @cinfo: SCMI channel info * @shmem: Transmit/Receive shared memory area + * @shmem_lock: Lock to protect access to Tx/Rx shared memory area * @func_id: smc/hvc call function id */ From 02c003cc18dfb6db1001856fccb978a1179fe89a Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Fri, 10 Jul 2020 14:39:17 +0100 Subject: [PATCH 18/20] firmware: arm_scmi: Remove zero-length array in SCMI notifications Substitute zero-length array defined in scmi_base_error_report with a flexible length array definition. Link: https://lore.kernel.org/r/20200710133919.39792-1-cristian.marussi@arm.com Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- include/linux/scmi_protocol.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 46d98be92466..7d4348fb7330 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -421,7 +421,7 @@ struct scmi_base_error_report { u32 agent_id; bool fatal; u16 cmd_count; - u64 reports[0]; + u64 reports[]; }; #endif /* _LINUX_SCMI_PROTOCOL_H */ From 33ee97f823cc5b3d03c9910c1b8dbe193a21056b Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Fri, 10 Jul 2020 14:39:18 +0100 Subject: [PATCH 19/20] firmware: arm_scmi: Remove unneeded __packed attribute Remove __packed attribute from struct scmi_event_header. Link: https://lore.kernel.org/r/20200710133919.39792-2-cristian.marussi@arm.com Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/notify.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c index c4d006cfde88..752415367305 100644 --- a/drivers/firmware/arm_scmi/notify.c +++ b/drivers/firmware/arm_scmi/notify.c @@ -258,7 +258,7 @@ struct scmi_event_header { u8 evt_id; size_t payld_sz; u8 payld[]; -} __packed; +}; struct scmi_registered_event; From 72a5eb9d9c319c99c11cfd9cfb486380dd136840 Mon Sep 17 00:00:00 2001 From: Cristian Marussi Date: Fri, 10 Jul 2020 14:39:19 +0100 Subject: [PATCH 20/20] firmware: arm_scmi: Remove fixed size fields from reports/scmi_event_header Event reports are used to convey information describing events to the registered user-callbacks: they are necessarily derived from the underlying raw SCMI events' messages but they are not meant to expose or directly mirror any of those messages data layout, which belong to the protocol layer. Using fixed size types for report fields, mirroring messages structure, is at odd with this: get rid of them using more generic, equivalent, typing. Substitute scmi_event_header fixed size fields with generic types too and shuffle around fields definitions to minimize implicit padding while adapting involved functions. Link: https://lore.kernel.org/r/20200710133919.39792-3-cristian.marussi@arm.com Signed-off-by: Cristian Marussi Signed-off-by: Sudeep Holla --- drivers/firmware/arm_scmi/base.c | 2 +- drivers/firmware/arm_scmi/driver.c | 4 +-- drivers/firmware/arm_scmi/notify.c | 15 +++++---- drivers/firmware/arm_scmi/notify.h | 8 +++-- drivers/firmware/arm_scmi/perf.c | 2 +- drivers/firmware/arm_scmi/power.c | 2 +- drivers/firmware/arm_scmi/reset.c | 2 +- drivers/firmware/arm_scmi/sensors.c | 2 +- include/linux/scmi_protocol.h | 52 ++++++++++++++--------------- 9 files changed, 46 insertions(+), 43 deletions(-) diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c index 54f378e946f1..9853bd3c4d45 100644 --- a/drivers/firmware/arm_scmi/base.c +++ b/drivers/firmware/arm_scmi/base.c @@ -273,7 +273,7 @@ static int scmi_base_set_notify_enabled(const struct scmi_handle *handle, } static void *scmi_base_fill_custom_report(const struct scmi_handle *handle, - u8 evt_id, u64 timestamp, + u8 evt_id, ktime_t timestamp, const void *payld, size_t payld_sz, void *report, u32 *src_id) { diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 19a4287fc0f7..03ec74242c14 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -205,13 +205,13 @@ __scmi_xfer_put(struct scmi_xfers_info *minfo, struct scmi_xfer *xfer) static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr) { - u64 ts; struct scmi_xfer *xfer; struct device *dev = cinfo->dev; struct scmi_info *info = handle_to_scmi_info(cinfo->handle); struct scmi_xfers_info *minfo = &info->rx_minfo; + ktime_t ts; - ts = ktime_get_boottime_ns(); + ts = ktime_get_boottime(); xfer = scmi_xfer_get(cinfo->handle, minfo); if (IS_ERR(xfer)) { dev_err(dev, "failed to get free message slot (%ld)\n", diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c index 752415367305..4731daaacd19 100644 --- a/drivers/firmware/arm_scmi/notify.c +++ b/drivers/firmware/arm_scmi/notify.c @@ -80,6 +80,7 @@ #include #include #include +#include #include #include #include @@ -246,18 +247,18 @@ struct events_queue { * struct scmi_event_header - A utility header * @timestamp: The timestamp, in nanoseconds (boottime), which was associated * to this event as soon as it entered the SCMI RX ISR - * @evt_id: Event ID (corresponds to the Event MsgID for this Protocol) * @payld_sz: Effective size of the embedded message payload which follows + * @evt_id: Event ID (corresponds to the Event MsgID for this Protocol) * @payld: A reference to the embedded event payload * * This header is prepended to each received event message payload before * queueing it on the related &struct events_queue. */ struct scmi_event_header { - u64 timestamp; - u8 evt_id; - size_t payld_sz; - u8 payld[]; + ktime_t timestamp; + size_t payld_sz; + unsigned char evt_id; + unsigned char payld[]; }; struct scmi_registered_event; @@ -572,7 +573,7 @@ static void scmi_events_dispatcher(struct work_struct *work) * Return: 0 on Success */ int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, - const void *buf, size_t len, u64 ts) + const void *buf, size_t len, ktime_t ts) { struct scmi_registered_event *r_evt; struct scmi_event_header eh; @@ -595,7 +596,7 @@ int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, if (kfifo_avail(&r_evt->proto->equeue.kfifo) < sizeof(eh) + len) { dev_warn(handle->dev, "queue full, dropping proto_id:%d evt_id:%d ts:%lld\n", - proto_id, evt_id, ts); + proto_id, evt_id, ktime_to_ns(ts)); return -ENOMEM; } diff --git a/drivers/firmware/arm_scmi/notify.h b/drivers/firmware/arm_scmi/notify.h index 3791bb7aa79b..3485f20fa70e 100644 --- a/drivers/firmware/arm_scmi/notify.h +++ b/drivers/firmware/arm_scmi/notify.h @@ -10,6 +10,7 @@ #define _SCMI_NOTIFY_H #include +#include #include #define SCMI_PROTO_QUEUE_SZ 4096 @@ -48,8 +49,9 @@ struct scmi_event_ops { int (*set_notify_enabled)(const struct scmi_handle *handle, u8 evt_id, u32 src_id, bool enabled); void *(*fill_custom_report)(const struct scmi_handle *handle, - u8 evt_id, u64 timestamp, const void *payld, - size_t payld_sz, void *report, u32 *src_id); + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id); }; int scmi_notification_init(struct scmi_handle *handle); @@ -61,6 +63,6 @@ int scmi_register_protocol_events(const struct scmi_handle *handle, const struct scmi_event *evt, int num_events, int num_sources); int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, - const void *buf, size_t len, u64 ts); + const void *buf, size_t len, ktime_t ts); #endif /* _SCMI_NOTIFY_H */ diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c index 8bcad96e06ca..3e1e87012c95 100644 --- a/drivers/firmware/arm_scmi/perf.c +++ b/drivers/firmware/arm_scmi/perf.c @@ -780,7 +780,7 @@ static int scmi_perf_set_notify_enabled(const struct scmi_handle *handle, } static void *scmi_perf_fill_custom_report(const struct scmi_handle *handle, - u8 evt_id, u64 timestamp, + u8 evt_id, ktime_t timestamp, const void *payld, size_t payld_sz, void *report, u32 *src_id) { diff --git a/drivers/firmware/arm_scmi/power.c b/drivers/firmware/arm_scmi/power.c index 4f6757980739..46f213644c49 100644 --- a/drivers/firmware/arm_scmi/power.c +++ b/drivers/firmware/arm_scmi/power.c @@ -227,7 +227,7 @@ static int scmi_power_set_notify_enabled(const struct scmi_handle *handle, } static void *scmi_power_fill_custom_report(const struct scmi_handle *handle, - u8 evt_id, u64 timestamp, + u8 evt_id, ktime_t timestamp, const void *payld, size_t payld_sz, void *report, u32 *src_id) { diff --git a/drivers/firmware/arm_scmi/reset.c b/drivers/firmware/arm_scmi/reset.c index fb7cb517900b..3691bafca057 100644 --- a/drivers/firmware/arm_scmi/reset.c +++ b/drivers/firmware/arm_scmi/reset.c @@ -240,7 +240,7 @@ static int scmi_reset_set_notify_enabled(const struct scmi_handle *handle, } static void *scmi_reset_fill_custom_report(const struct scmi_handle *handle, - u8 evt_id, u64 timestamp, + u8 evt_id, ktime_t timestamp, const void *payld, size_t payld_sz, void *report, u32 *src_id) { diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c index 2120ac4787c9..1af0ad362e82 100644 --- a/drivers/firmware/arm_scmi/sensors.c +++ b/drivers/firmware/arm_scmi/sensors.c @@ -296,7 +296,7 @@ static int scmi_sensor_set_notify_enabled(const struct scmi_handle *handle, } static void *scmi_sensor_fill_custom_report(const struct scmi_handle *handle, - u8 evt_id, u64 timestamp, + u8 evt_id, ktime_t timestamp, const void *payld, size_t payld_sz, void *report, u32 *src_id) { diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 7d4348fb7330..7e5dd7d1e221 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -381,47 +381,47 @@ enum scmi_notification_events { }; struct scmi_power_state_changed_report { - u64 timestamp; - u32 agent_id; - u32 domain_id; - u32 power_state; + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int power_state; }; struct scmi_perf_limits_report { - u64 timestamp; - u32 agent_id; - u32 domain_id; - u32 range_max; - u32 range_min; + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int range_max; + unsigned int range_min; }; struct scmi_perf_level_report { - u64 timestamp; - u32 agent_id; - u32 domain_id; - u32 performance_level; + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int performance_level; }; struct scmi_sensor_trip_point_report { - u64 timestamp; - u32 agent_id; - u32 sensor_id; - u32 trip_point_desc; + ktime_t timestamp; + unsigned int agent_id; + unsigned int sensor_id; + unsigned int trip_point_desc; }; struct scmi_reset_issued_report { - u64 timestamp; - u32 agent_id; - u32 domain_id; - u32 reset_state; + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int reset_state; }; struct scmi_base_error_report { - u64 timestamp; - u32 agent_id; - bool fatal; - u16 cmd_count; - u64 reports[]; + ktime_t timestamp; + unsigned int agent_id; + bool fatal; + unsigned int cmd_count; + unsigned long long reports[]; }; #endif /* _LINUX_SCMI_PROTOCOL_H */