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@xxxxxxxxxxxxx>
---
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 8face57c4180..f1bd7c035db8 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 |
--
2.40.1
