6.4-stable review patch. If anyone has any objections, please let me know.
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From: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com
[ Upstream commit 9f3fef23d9b5a858a6e6d5f478bb1b6b76265e76 ]
Writing the new TTBRs, TCRs and MAIRs on a previously enabled context bank may trigger a context fault, resulting in firmware driven AP resets: change the domain initialization programming sequence to disable the context bank(s) and to also clear the related fault address (CB_FAR) and fault status (CB_FSR) registers before writing new values to TTBR0/1, TCR/TCR2, MAIR0/1.
Fixes: 0ae349a0f33f ("iommu/qcom: Add qcom_iommu") Signed-off-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Reviewed-by: Konrad Dybcio konrad.dybcio@linaro.org Link: https://lore.kernel.org/r/20230622092742.74819-4-angelogioacchino.delregno@c... Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c index a503ed758ec30..3e551ca6afdb9 100644 --- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c +++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c @@ -273,6 +273,13 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, ctx->secure_init = true; }
+ /* Disable context bank before programming */ + iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0); + + /* Clear context bank fault address fault status registers */ + iommu_writel(ctx, ARM_SMMU_CB_FAR, 0); + iommu_writel(ctx, ARM_SMMU_CB_FSR, ARM_SMMU_FSR_FAULT); + /* TTBRs */ iommu_writeq(ctx, ARM_SMMU_CB_TTBR0, pgtbl_cfg.arm_lpae_s1_cfg.ttbr |