2024-06-04 15:02:08

by Rob Clark

[permalink] [raw]
Subject: [PATCH] iommu/arm-smmu: Pretty-print context fault related regs

From: Rob Clark <[email protected]>

Parse out the bitfields for easier-to-read fault messages.

Signed-off-by: Rob Clark <[email protected]>
---
Stephen was wanting easier to read fault messages.. so I typed this up.

Resend with the new iommu list address

drivers/iommu/arm/arm-smmu/arm-smmu.c | 53 +++++++++++++++++++++++++--
drivers/iommu/arm/arm-smmu/arm-smmu.h | 5 +++
2 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index c572d877b0e1..06712d73519c 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -411,6 +411,8 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
unsigned long iova;
struct arm_smmu_domain *smmu_domain = dev;
struct arm_smmu_device *smmu = smmu_domain->smmu;
+ static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL,
+ DEFAULT_RATELIMIT_BURST);
int idx = smmu_domain->cfg.cbndx;
int ret;

@@ -425,10 +427,53 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
ret = report_iommu_fault(&smmu_domain->domain, NULL, iova,
fsynr & ARM_SMMU_FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ);

- if (ret == -ENOSYS)
- dev_err_ratelimited(smmu->dev,
- "Unhandled context fault: fsr=0x%x, iova=0x%08lx, fsynr=0x%x, cbfrsynra=0x%x, cb=%d\n",
- fsr, iova, fsynr, cbfrsynra, idx);
+ if (ret == -ENOSYS && __ratelimit(&rs)) {
+ static const struct {
+ u32 mask; const char *name;
+ } fsr_bits[] = {
+ { ARM_SMMU_FSR_MULTI, "MULTI" },
+ { ARM_SMMU_FSR_SS, "SS" },
+ { ARM_SMMU_FSR_UUT, "UUT" },
+ { ARM_SMMU_FSR_ASF, "ASF" },
+ { ARM_SMMU_FSR_TLBLKF, "TLBLKF" },
+ { ARM_SMMU_FSR_TLBMCF, "TLBMCF" },
+ { ARM_SMMU_FSR_EF, "EF" },
+ { ARM_SMMU_FSR_PF, "PF" },
+ { ARM_SMMU_FSR_AFF, "AFF" },
+ { ARM_SMMU_FSR_TF, "TF" },
+ }, fsynr0_bits[] = {
+ { ARM_SMMU_FSYNR0_WNR, "WNR" },
+ { ARM_SMMU_FSYNR0_PNU, "PNU" },
+ { ARM_SMMU_FSYNR0_IND, "IND" },
+ { ARM_SMMU_FSYNR0_NSATTR, "NSATTR" },
+ { ARM_SMMU_FSYNR0_PTWF, "PTWF" },
+ { ARM_SMMU_FSYNR0_AFR, "AFR" },
+ };
+
+ pr_err("%s %s: Unhandled context fault: fsr=0x%x (",
+ dev_driver_string(smmu->dev), dev_name(smmu->dev), fsr);
+
+ for (int i = 0, n = 0; i < ARRAY_SIZE(fsr_bits); i++) {
+ if (fsr & fsr_bits[i].mask) {
+ pr_cont("%s%s", (n > 0) ? "|" : "", fsr_bits[i].name);
+ n++;
+ }
+ }
+
+ pr_cont("), iova=0x%08lx, fsynr=0x%x (S1CBNDX=%u", iova, fsynr,
+ (fsynr >> 16) & 0xff);
+
+ for (int i = 0; i < ARRAY_SIZE(fsynr0_bits); i++) {
+ if (fsynr & fsynr0_bits[i].mask) {
+ pr_cont("|%s", fsynr0_bits[i].name);
+ }
+ }
+
+ pr_cont("|PLVL=%u), cbfrsynra=0x%x, cb=%d\n",
+ fsynr & 0x3, /* FSYNR0.PLV */
+ cbfrsynra, idx);
+
+ }

arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
return IRQ_HANDLED;
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.h b/drivers/iommu/arm/arm-smmu/arm-smmu.h
index 836ed6799a80..3b051273718b 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.h
@@ -223,6 +223,11 @@ enum arm_smmu_cbar_type {

#define ARM_SMMU_CB_FSYNR0 0x68
#define ARM_SMMU_FSYNR0_WNR BIT(4)
+#define ARM_SMMU_FSYNR0_PNU BIT(5)
+#define ARM_SMMU_FSYNR0_IND BIT(6)
+#define ARM_SMMU_FSYNR0_NSATTR BIT(8)
+#define ARM_SMMU_FSYNR0_PTWF BIT(10)
+#define ARM_SMMU_FSYNR0_AFR BIT(11)

#define ARM_SMMU_CB_FSYNR1 0x6c

--
2.45.1