This patch has a fix to enable PLLP branches to CPU before changing
the CPU cluster clock source to PLLP for Gen5 Super clock and
disables PLLP branches to CPU when not in use.
During system suspend entry and exit, CPU source will be switched
to PLLP and this needs PLLP branches to be enabled to CPU prior to
the switch.
On system resume, warmboot code enables PLLP branches to CPU and
powers up the CPU with PLLP clock source.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch implements restore_context support for clk-periph and
clk-sdmmc-mux clock operations to restore clock parent and rates
on system resume.
During system suspend, core power goes off and looses the context
of the Tegra clock controller registers.
So on system resume, clocks parent and rate are restored back to
the context before suspend based on cached data.
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch adds support for saving OSC clock frequency and the
drive-strength during OSC clock init and creates an API to restore
OSC control register value from the saved context.
This API is invoked by Tegra210 clock driver during system resume
to restore the OSC clock settings.
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch implements save and restore of PLL context.
During system suspend, core power goes off and looses the settings
of the Tegra CAR controller registers.
So during resume, pll context is restored based on cached rate
and state.
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch implements save and restore of pllout context.
During system suspend, core power goes off and looses the settings
of the Tegra CAR controller registers.
So during suspend entry the state of pllout is saved and on resume
it is restored back to have pllout in same state as before suspend.
pllout rate is saved and restore in clock divider so it will be at
same rate as before suspend when pllout state is restored.
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch implements context restore for clock divider.
During system suspend, core power goes off and looses the settings
of the Tegra CAR controller registers.
So on resume, clock dividers are restored back for normal operation.
Acked-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
In order to allow the display driver to deal uniformly with all SOR
generations, implement the SOR clocks in a way that is compatible with
Tegra186 and later.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
In order to allow the display driver to deal uniformly with all SOR
generations, implement the SOR clocks in a way that is compatible with
Tegra186 and later.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This makes Tegra124 and Tegra210 consistent with subsequent Tegra
generations.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
The SOR0 clock on Tegra210 is very different from the SOR0 clock found
on Tegra124. Move the Tegra124 implementation to the Tegra124 driver so
that a custom implementation can be provided on Tegra210 without
clashing with the existing clock.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Later SoC generations implement this clock as SOR1_OUT. For consistency,
the Tegra210 implementation was adapted to match the same name in commit
4d1dc40185 ("dt-bindings: clock: tegra: Add sor1_out clock").
Clean up the remaining pieces by adopting the new name for the internal
identifiers and remove the old alias. Note that since both SOR1_SRC and
SOR1_OUT were referring to the same device tree clock ID, this does not
break device tree ABI.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Apply same logic to pin setup as on previous platforms. Fixes
errors in HDMI/DP playback.
Tested with both snd-hda-intel and SOF drivers.
Fixes: 9a11ba7388 ("ALSA: hda: hdmi - add Tigerlake support")
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20191111133838.21213-1-kai.vehmanen@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
In case of a timeout or if a signal aborts a read
communication with the device needs to be ended
lest we overwrite an active URB the next time we
do IO to the device, as the URB may still be active.
Signed-off-by: Oliver Neukum <oneukum@suse.de>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20191107142856.16774-1-oneukum@suse.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add connector binding documentation for Richtek RT1711H Type-C
chip driver
It was noted by Rob Herring that the rt1711h binding docs
doesn't include the connector binding.
Thus this patch adds such documentation following the details
in Documentation/devicetree/bindings/usb/typec-tcpci.txt
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
CC: ShuFan Lee <shufan_lee@richtek.com>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Chunfeng Yun <chunfeng.yun@mediatek.com>
Cc: Yu Chen <chenyu56@huawei.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Jun Li <lijun.kernel@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: linux-usb@vger.kernel.org
Cc: devicetree@vger.kernel.org
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Link: https://lore.kernel.org/r/20191108005657.31464-1-john.stultz@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With latest llvm compiler, running test_progs will have the following
verifier failure for test_sysctl_loop1.o:
libbpf: load bpf program failed: Permission denied
libbpf: -- BEGIN DUMP LOG ---
libbpf:
invalid indirect read from stack var_off (0x0; 0xff)+196 size 7
...
libbpf: -- END LOG --
libbpf: failed to load program 'cgroup/sysctl'
libbpf: failed to load object 'test_sysctl_loop1.o'
The related bytecode looks as below:
0000000000000308 LBB0_8:
97: r4 = r10
98: r4 += -288
99: r4 += r7
100: w8 &= 255
101: r1 = r10
102: r1 += -488
103: r1 += r8
104: r2 = 7
105: r3 = 0
106: call 106
107: w1 = w0
108: w1 += -1
109: if w1 > 6 goto -24 <LBB0_5>
110: w0 += w8
111: r7 += 8
112: w8 = w0
113: if r7 != 224 goto -17 <LBB0_8>
And source code:
for (i = 0; i < ARRAY_SIZE(tcp_mem); ++i) {
ret = bpf_strtoul(value + off, MAX_ULONG_STR_LEN, 0,
tcp_mem + i);
if (ret <= 0 || ret > MAX_ULONG_STR_LEN)
return 0;
off += ret & MAX_ULONG_STR_LEN;
}
Current verifier is not able to conclude that register w0 before '+'
at insn 110 has a range of 1 to 7 and thinks it is from 0 - 255. This
leads to more conservative range for w8 at insn 112, and later verifier
complaint.
Let us workaround this issue until we found a compiler and/or verifier
solution. The workaround in this patch is to make variable 'ret' volatile,
which will force a reload and then '&' operation to ensure better value
range. With this patch, I got the below byte code for the loop:
0000000000000328 LBB0_9:
101: r4 = r10
102: r4 += -288
103: r4 += r7
104: w8 &= 255
105: r1 = r10
106: r1 += -488
107: r1 += r8
108: r2 = 7
109: r3 = 0
110: call 106
111: *(u32 *)(r10 - 64) = r0
112: r1 = *(u32 *)(r10 - 64)
113: if w1 s< 1 goto -28 <LBB0_5>
114: r1 = *(u32 *)(r10 - 64)
115: if w1 s> 7 goto -30 <LBB0_5>
116: r1 = *(u32 *)(r10 - 64)
117: w1 &= 7
118: w1 += w8
119: r7 += 8
120: w8 = w1
121: if r7 != 224 goto -21 <LBB0_9>
Insn 117 did the '&' operation and we got more precise value range
for 'w8' at insn 120. The test is happy then:
#3/17 test_sysctl_loop1.o:OK
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191107170045.2503480-1-yhs@fb.com
The RT5677 DSP needs the I2S MCLK1 to run its DSP. Add a dapm route to
SSP0 CODEC IN so the clock is turned on automatically when the DSP is
turned on.
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-10-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Due to limitations of the clocking configuration, we have no way of
scheduling our hibernation before the bdw dsp hibernates. This causes
issues when the system suspends with an open stream. We need userspace
to toggle the kcontrol before we are suspended so that any writes on
suspend are not lost and we don't corrupt the regmap.
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-9-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The irq is disabled at suspend to avoid running the threaded irq
handler after the codec has been powered off. At resume, codec irq is
re-enabled and the interrupt status register is checked to see if
headphone has been pluggnd/unplugged while the device is suspended.
There is still a chance that the headphone gets enabled or disabled
after the codec is suspended. disable_irq syncs the threaded irq
handler, but soc-jack's threaded irq handler schedules a delayed
work to poll gpios (for debounce). This is still OK. The codec won't
be powered back on again because all audio paths have been suspended,
and there are no force enabled supply widgets (MICBIAS1 is disabled).
The gpio status read after codec power off could be wrong, so the
gpio values are checked again after resume.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-8-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
MCLK1 gets disabled at suspend and re-enabled at resume. Before
MCLK1 is re-enabled, if the DSP is already on (either the DSP was
left on during suspend, or the DSP is turned on early at resume),
i2c register read returns garbage and corrupts the regmap cache.
This patch stops the DSP before suspend and restarts it after
resume with a dalay to ensure MCLK is on while loading firmware.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-7-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The codec dies when RT5677_PWR_ANLG2(MX-64h) is set to 0xACE1
while it's streaming audio over SPI. The DSP firmware turns
on PLL2 (MX-64 bit 8) when SPI streaming starts. However regmap
does not believe that register can change by itself. When
BST1 (bit 15) is turned on with regmap_update_bits(), it doesn't
read the register first before write, so PLL2 power bit is
cleared by accident.
Marking MX-64h as volatile in regmap solved the issue.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-6-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Add a DAPM audio path from "DMIC L1" to "DSP Buffer" so that
when hotwording is enabled, DAPM does not power off the codec
with SND_SOC_BIAS_OFF.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-5-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Before a hotword is detected, GPIO1 pin is configured as IRQ
output so that jack detect works. When a hotword is detected,
the DSP firmware configures the GPIO1 pin as GPIO1 and
drives a 1. rt5677_irq() is called after a rising edge on
the GPIO1 pin, due to either jack detect event or hotword
event, or both. All possible events are checked and handled
in rt5677_irq() where GPIO1 pin is configured back to IRQ
output if a hotword is detected.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-4-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The firmware rt5677_elf_vad is an ELF binary obtained from
request_firmware(). Sections of the ELF are loaded to
the DSP via SPI. A model (e.g. en_us.mmap) can optionally be
loaded to the DSP at RT5677_MODEL_ADDR to overwrite the
baked-in model in rt5677_elf_vad.
Then we switch to DSP mode, load firmware, and let DSP run.
When a hotword is detected, an interrupt is fired and
rt5677_irq() is called. When 'DSP VAD Switch' is turned off,
the codec is set back to normal mode.
The kcontrol 'DSP VAD Switch' is automatically enabled/disabled
when the hotwording PCM stream is opened/closed.
Signed-off-by: Ben Zhang <benzh@chromium.org>
Signed-off-by: Curtis Malainey <cujomalainey@chromium.org>
Link: https://lore.kernel.org/r/20191106011335.223061-2-cujomalainey@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Audmix support two substream, When two substream start
to run, the trigger function may be called by two substream
in same time, that the priv->tdms may be updated wrongly.
The expected priv->tdms is 0x3, but sometimes the
result is 0x2, or 0x1.
Fixes: be1df61cf0 ("ASoC: fsl: Add Audio Mixer CPU DAI driver")
Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Link: https://lore.kernel.org/r/1e706afe53fdd1fbbbc79277c48a98f8416ba873.1573458378.git.shengjiu.wang@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: <stable@vger.kernel.org>
A proper External Memory Controller clock rounding and parent selection
functionality is required by the EMC drivers, it is not available using
the generic clock implementation because only the Memory Controller driver
is aware of what clock rates are actually available for a particular
device. EMC drivers will have to register a Tegra-specific CLK-API
callback which will perform rounding of a requested rate. EMC clock users
won't be able to request EMC clock by getting -EPROBE_DEFER until EMC
driver is probed and the callback is set up.
The functionality is somewhat similar to the clk-emc.c which serves
Tegra124+ SoCs. The later HW generations support more parent clock sources
and the HW configuration / integration with the EMC drivers differs a tad
from the older gens, hence it's not really worth to try to squash
everything into a single source file.
Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
This patch adds a new clk_hw_get_parent_index() function that can be
used to retrieve the index of a given clock's parent. This can be useful
for restoring a clock on system resume.
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
pxa2xx_spi_init_pdata misses checks for devm_clk_get and
platform_get_irq.
Add checks for them to fix the bugs.
Since ssp->clk and ssp->irq are used in probe, they are mandatory here.
So we cannot use _optional() for devm_clk_get and platform_get_irq.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Link: https://lore.kernel.org/r/20191109080943.30428-1-hslester96@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This driver forgets to unregister controller when remove.
Use devm API to unregister it automatically to fix it.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Link: https://lore.kernel.org/r/20191109075517.29988-1-hslester96@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Both omap2_mcspi_tx_dma() and omap2_mcspi_rx_dma() are only called from
omap2_mcspi_txrx_dma() and omap2_mcspi_txrx_dma() is always called after
making sure that mcspi_dma->dma_rx and mcspi_dma->dma_tx are not NULL
(see omap2_mcspi_transfer_one()).
Therefore remove redundant NULL checks for omap2_mcspi->dma_tx and
omap2_mcspi->dma_rx pointers in omap2_mcspi_tx_dma() and
omap2_mcspi_rx_dma() respectively.
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20191109041827.26934-1-vigneshr@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The probe function in the gpio-backlight driver is quite short. If we
pull gpio_backlight_initial_power_state() into probe we can drop two
more fields from struct gpio_backlight and shrink the driver code.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Instead of dereferencing pdev each time, use a helper variable for
the associated device pointer.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Remove the platform data fields that nobody uses.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Platform data fields other than fbdev are no longer used by the
backlight driver. Remove them.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Now that the last user of platform data (sh ecovec24) defines a proper
GPIO lookup and sets the 'default-on' device property, we can drop the
platform_data-specific GPIO handling and unify a big chunk of code.
The only field used from the platform data is now the fbdev pointer.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Add a GPIO lookup entry and a device property for GPIO backlight to the
board file. Tie them to the platform device which is now registered using
platform_device_register_full() because of the properties. These changes
are inactive now but will be used once the gpio backlight driver is
modified.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The GPIO backlight driver currently requests the line 'as is', without
acively setting its direction. This can lead to problems: if the line
is in input mode by default, we won't be able to drive it later when
updating the status and also reading its initial value doesn't make
sense for backlight setting.
Request the line 'as is' initially, so that we can read its value
without affecting it but then change the direction to output explicitly
when setting the initial brightness.
Also: check the current direction and only read the value if it's output.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Remove a double newline from the driver.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
We no longer use any symbols from of_gpio.h. Remove this include.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
It is possible that platform_get_resource() might return NULL and
therefore code needs to check for this condition before
de-referencing the pointer.
Therefore move the de-referencing of 'res' pointer after
devm_ioremap_resource() which would have checked the validity of the
pointer.
Reported-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Make bit definitions static to reduce the scope.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Until now, MFD has assumed all child devices passed to it (via
mfd_cells) are to be registered. It does not take into account
requests from Device Tree and the like to disable child devices
on a per-platform basis.
Well now it does.
Link: https://www.spinics.net/lists/arm-kernel/msg366309.html
Link: https://lkml.org/lkml/2019/8/22/1350
Reported-by: Barry Song <Baohua.Song@csr.com>
Reported-by: Stephan Gerhold <stephan@gerhold.net>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
GNU Make manual says:
$?
The names of all the prerequisites that are newer than the target,
with spaces between them.
To reflect this, rename any-prereq to newer-prereqs, which is clearer
and more intuitive.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The incremental build of Linux kernel is pretty slow when lots of
objects are compiled. The rebuild of allmodconfig may take a few
minutes even when none of the objects needs to be rebuilt.
The time-consuming part in the incremental build is the evaluation of
if_changed* macros since they are used in the recipes to compile C and
assembly source files into objects.
I notice the following code in if_changed* is expensive:
$(filter-out $(PHONY) $(wildcard $^),$^)
In the incremental build, every object has its .*.cmd file, which
contains the auto-generated list of included headers. So, $^ are
expanded into the long list of the source file + included headers,
and $(wildcard $^) checks whether they exist.
It may not be clear why this check exists there.
Here is the record of my research.
[1] The first code addition into Kbuild
This code dates back to 2002. It is the pre-git era. So, I copy-pasted
it from the historical git tree.
| commit 4a6db0791528c220655b063cf13fefc8470dbfee (HEAD)
| Author: Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de>
| Date: Mon Jun 17 00:22:37 2002 -0500
|
| kbuild: Handle removed headers
|
| New and old way to handle dependencies would choke when a file
| #include'd by other files was removed, since the dependency on it was
| still recorded, but since it was gone, make has no idea what to do about
| it (and would complain with "No rule to make <file> ...")
|
| We now add targets for all the previously included files, so make will
| just ignore them if they disappear.
|
| diff --git a/Rules.make b/Rules.make
| index 6ef827d3df39..7db5301ea7db 100644
| --- a/Rules.make
| +++ b/Rules.make
| @@ -446,7 +446,7 @@ if_changed = $(if $(strip $? \
| # execute the command and also postprocess generated .d dependencies
| # file
|
| -if_changed_dep = $(if $(strip $? \
| +if_changed_dep = $(if $(strip $? $(filter-out FORCE $(wildcard $^),$^)\
| $(filter-out $(cmd_$(1)),$(cmd_$@))\
| $(filter-out $(cmd_$@),$(cmd_$(1)))),\
| @set -e; \
| diff --git a/scripts/fixdep.c b/scripts/fixdep.c
| index b5d7bee8efc7..db45bd1888c0 100644
| --- a/scripts/fixdep.c
| +++ b/scripts/fixdep.c
| @@ -292,7 +292,7 @@ void parse_dep_file(void *map, size_t len)
| exit(1);
| }
| memcpy(s, m, p-m); s[p-m] = 0;
| - printf("%s: \\\n", target);
| + printf("deps_%s := \\\n", target);
| m = p+1;
|
| clear_config();
| @@ -314,7 +314,8 @@ void parse_dep_file(void *map, size_t len)
| }
| m = p + 1;
| }
| - printf("\n");
| + printf("\n%s: $(deps_%s)\n\n", target, target);
| + printf("$(deps_%s):\n", target);
| }
|
| void print_deps(void)
The "No rule to make <file> ..." error can be solved by passing -MP to
the compiler, but I think the detection of header removal is a good
feature. When a header is removed, all source files that previously
included it should be re-compiled. This makes sure we has correctly
got rid of #include directives of it.
This is also related with the behavior of $?. The GNU Make manual says:
$?
The names of all the prerequisites that are newer than the target,
with spaces between them.
This does not explain whether a non-existent prerequisite is considered
to be newer than the target.
At this point of time, GNU Make 3.7x was used, where the $? did not
include non-existent prerequisites. Therefore,
$(filter-out FORCE $(wildcard $^),$^)
was useful to detect the header removal, and to rebuild the related
objects if it is the case.
[2] Change of $? behavior
Later, the behavior of $? was changed (fixed) to include prerequisites
that did not exist.
First, GNU Make commit 64e16d6c00a5 ("Various changes getting ready for
the release of 3.81.") changed it, but in the release test of 3.81, it
turned out to break the kernel build.
See these:
- http://lists.gnu.org/archive/html/bug-make/2006-03/msg00003.html
- https://savannah.gnu.org/bugs/?16002
- https://savannah.gnu.org/bugs/?16051
Then, GNU Make commit 6d8d9b74d9c5 ("Numerous updates to tests for
issues found on Cygwin and Windows.") reverted it for the 3.81 release
to give Linux kernel time to adjust to the new behavior.
After the 3.81 release, GNU Make commit 7595f38f62af ("Fixed a number
of documentation bugs, plus some build/install issues:") re-added it.
[3] Adjustment to the new $? behavior on Kbuild side
Meanwhile, the kernel build was changed by commit 4f1933620f ("kbuild:
change kbuild to not rely on incorrect GNU make behavior") to adjust to
the new $? behavior.
[4] GNU Make 3.82 released in 2010
GNU Make 3.82 was the first release that integrated the correct $?
behavior. At this point, Kbuild dealt with GNU Make versions with
different $? behaviors.
3.81 or older:
$? does not contain any non-existent prerequisite.
$(filter-out $(PHONY) $(wildcard $^),$^) was useful to detect
removed include headers.
3.82 or newer:
$? contains non-existent prerequisites. When a header is removed,
it appears in $?. $(filter-out $(PHONY) $(wildcard $^),$^) became
a redundant check.
With the correct $? behavior, we could have dropped the expensive
check for 3.82 or later, but we did not. (Maybe nobody noticed this
optimization.)
[5] The .SECONDARY special target trips up $?
Some time later, I noticed $? did not work as expected under some
circumstances. As above, $? should contain non-existent prerequisites,
but the ones specified as SECONDARY do not appear in $?.
I asked this in GNU Make ML, and it seems a bug:
https://lists.gnu.org/archive/html/bug-make/2019-01/msg00001.html
Since commit 8e9b61b293 ("kbuild: move .SECONDARY special target to
Kbuild.include"), all files, including headers listed in .*.cmd files,
are treated as secondary.
So, we are back into the incorrect $? behavior.
If we Kbuild want to react to the header removal, we need to keep
$(filter-out $(PHONY) $(wildcard $^),$^) but this makes the rebuild
so slow.
[Summary]
- I believe noticing the header removal and recompiling related objects
is a nice feature for the build system.
- If $? worked correctly, $(filter-out $(PHONY),$?) would be enough
to detect the header removal.
- Currently, $? does not work correctly when used with .SECONDARY,
and Kbuild is hit by this bug.
- I filed a bug report for this, but not fixed yet as of writing.
- Currently, the header removal is detected by the following expensive
code:
$(filter-out $(PHONY) $(wildcard $^),$^)
- I do not want to revert commit 8e9b61b293 ("kbuild: move
.SECONDARY special target to Kbuild.include"). Specifying
.SECONDARY globally is clean, and it matches to the Kbuild policy.
This commit proactively removes the expensive check since it makes the
incremental build faster. A downside is Kbuild will no longer be able
to notice the header removal.
You can confirm it by the full-build followed by a header removal, and
then re-build.
$ make defconfig all
[ full build ]
$ rm include/linux/device.h
$ make
CALL scripts/checksyscalls.sh
CALL scripts/atomic/check-atomics.sh
DESCEND objtool
CHK include/generated/compile.h
Kernel: arch/x86/boot/bzImage is ready (#11)
Building modules, stage 2.
MODPOST 12 modules
Previously, Kbuild noticed a missing header and emits a build error.
Now, Kbuild is fine with it. This is an unusual corner-case, not a big
deal. Once the $? bug is fixed in GNU Make, everything will work fine.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since commit 707816c8b0 ("netfilter: remove deprecation warnings from
uapi headers."), you can compile linux/netfilter_ipv4/ipt_LOG.h and
linux/netfilter_ipv6/ip6t_LOG.h without warnings.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
