kybaaz/linux-xiaomi-chiron
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

iommu/arm-smmu: Allow skipping context bank disable at reset time

Browse source 
On some SoCs some IOMMU context banks are actively used from TZ
during system boot, or some hypervisor configurations will trigger
a system reset upon disabling some protected/secured CBs.

Allow skipping the disablement of such contexts at IOMMU reset time
during initialization with a new implementation detail to work around
this quirk.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@somainline.org>
This commit is contained in:
AngeloGioacchino Del Regno 2021-08-06 13:14:41 +02:00 • committed by Jami Kettunen
parent 5d25ef59ae
commit 8058f9b46a
2 changed files with 11 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

10
drivers/iommu/arm/arm-smmu/arm-smmu.c
View file

@ -1622,6 +1622,16 @@ static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
/* Make sure all context banks are disabled and clear CB_FSR */
for (i = 0; i < smmu->num_context_banks; ++i) {
/*
* Some context banks cannot be disabled due to hypervisor
* configuration on some systems; if this is the case,
* skip disabling and writing FAULT on the CB FSR in order
* to avoid a system crash.
*/
if (smmu->impl && smmu->impl->reset_cb_nodisable &&
smmu->impl->reset_cb_nodisable(smmu, i)) {
continue;
}
arm_smmu_write_context_bank(smmu, i);
arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_FSR, ARM_SMMU_FSR_FAULT);
}

1
drivers/iommu/arm/arm-smmu/arm-smmu.h
View file

@ -430,6 +430,7 @@ struct arm_smmu_impl {
u64 val);
int (*cfg_probe)(struct arm_smmu_device *smmu);
int (*reset)(struct arm_smmu_device *smmu);
bool (*reset_cb_nodisable)(struct arm_smmu_device *smmu, int cbndx);
int (*init_context)(struct arm_smmu_domain *smmu_domain,
struct io_pgtable_cfg *cfg, struct device *dev);
void (*tlb_sync)(struct arm_smmu_device *smmu, int page, int sync,