On 01/10/2019 23:02, kholk11@xxxxxxxxx wrote:
From: AngeloGioacchino Del Regno <kholk11@xxxxxxxxx>
To avoid context faults reset the context entirely on detach and
to ensure a fresh clean start also do a complete reset before
programming the context for domain initialization.
Signed-off-by: AngeloGioacchino Del Regno <kholk11@xxxxxxxxx>
---
drivers/iommu/qcom_iommu.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c
index c8957ec83b92..b4a38ef129e3 100644
--- a/drivers/iommu/qcom_iommu.c
+++ b/drivers/iommu/qcom_iommu.c
@@ -220,6 +220,23 @@ static irqreturn_t qcom_iommu_fault(int irq, void *dev)
return IRQ_HANDLED;
}
+static void qcom_iommu_reset_ctx(struct qcom_iommu_ctx *ctx)
+{
+ iommu_writel(ctx, ARM_SMMU_CB_FAR, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_FSR, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_S1_MAIR1, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_PAR, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_S1_MAIR0, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_TCR2, 0);
+ iommu_writel(ctx, ARM_SMMU_CB_TCR, 0);
+ iommu_writeq(ctx, ARM_SMMU_CB_TTBR0, 0);
+ iommu_writeq(ctx, ARM_SMMU_CB_TTBR1, 0);
+
+ /* Should we issue a TLBSYNC there instead? */
Unless there are outstanding TLB invalidations, it wouldn't achieve
much. That said, doing a TBLIALL as part of the reset sequence *would*
generally be a good idea.
Also, since the write to SCTLR affects the overall enable state of the
context bank, it would be best to do that before touching anything else.
Robin.
+ mb();
+}
+
static int qcom_iommu_init_domain(struct iommu_domain *domain,
struct qcom_iommu_dev *qcom_iommu,
struct iommu_fwspec *fwspec)
@@ -267,6 +284,8 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain,
ctx->secure_init = true;
}
+ qcom_iommu_reset_ctx(ctx);
+
/* TCR */
iommu_writel(ctx, ARM_SMMU_CB_TCR2,
(pgtbl_cfg.arm_lpae_s1_cfg.tcr >> 32) |
@@ -412,8 +431,8 @@ static void qcom_iommu_detach_dev(struct iommu_domain *domain, struct device *de
for (i = 0; i < fwspec->num_ids; i++) {
struct qcom_iommu_ctx *ctx = to_ctx(fwspec, fwspec->ids[i]);
- /* Disable the context bank: */
- iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);
+ /* Disable and reset the context bank */
+ qcom_iommu_reset_ctx(ctx);
ctx->domain = NULL;
}
