iommu/arm-smmu: Pretty-print context fault related regs

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

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Pranjal Shrivastava <praan@google.com>
Link: https://lore.kernel.org/r/20240701162025.375134-4-robdclark@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>

3 files changed, 92 insertions, 51 deletions

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
index 681fbdfc325d..ef93f825f11f 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom-debug.c
@@ -383,64 +383,44 @@ irqreturn_t qcom_smmu_context_fault(int irq, void *dev)
 	struct arm_smmu_domain *smmu_domain = dev;
 	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
 	struct arm_smmu_device *smmu = smmu_domain->smmu;
-	u32 fsr, fsynr, cbfrsynra, resume = 0;
+	struct arm_smmu_context_fault_info cfi;
+	u32 resume = 0;
 	int idx = smmu_domain->cfg.cbndx;
 	phys_addr_t phys_soft;
-	unsigned long iova;
 	int ret, tmp;
 
 	static DEFINE_RATELIMIT_STATE(_rs,
 				      DEFAULT_RATELIMIT_INTERVAL,
 				      DEFAULT_RATELIMIT_BURST);
 
-	fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
-	if (!(fsr & ARM_SMMU_CB_FSR_FAULT))
-		return IRQ_NONE;
+	arm_smmu_read_context_fault_info(smmu, idx, &cfi);
 
-	fsynr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSYNR0);
-	iova = arm_smmu_cb_readq(smmu, idx, ARM_SMMU_CB_FAR);
-	cbfrsynra = arm_smmu_gr1_read(smmu, ARM_SMMU_GR1_CBFRSYNRA(idx));
+	if (!(cfi.fsr & ARM_SMMU_CB_FSR_FAULT))
+		return IRQ_NONE;
 
 	if (list_empty(&tbu_list)) {
-		ret = report_iommu_fault(&smmu_domain->domain, NULL, iova,
-					 fsynr & ARM_SMMU_CB_FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ);
+		ret = report_iommu_fault(&smmu_domain->domain, NULL, cfi.iova,
+					 cfi.fsynr & ARM_SMMU_CB_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);
+			arm_smmu_print_context_fault_info(smmu, idx, &cfi);
 
-		arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
+		arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, cfi.fsr);
 		return IRQ_HANDLED;
 	}
 
-	phys_soft = ops->iova_to_phys(ops, iova);
+	phys_soft = ops->iova_to_phys(ops, cfi.iova);
 
-	tmp = report_iommu_fault(&smmu_domain->domain, NULL, iova,
-				 fsynr & ARM_SMMU_CB_FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ);
+	tmp = report_iommu_fault(&smmu_domain->domain, NULL, cfi.iova,
+				 cfi.fsynr & ARM_SMMU_CB_FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ);
 	if (!tmp || tmp == -EBUSY) {
 		ret = IRQ_HANDLED;
 		resume = ARM_SMMU_RESUME_TERMINATE;
 	} else {
-		phys_addr_t phys_atos = qcom_smmu_verify_fault(smmu_domain, iova, fsr);
+		phys_addr_t phys_atos = qcom_smmu_verify_fault(smmu_domain, cfi.iova, cfi.fsr);
 
 		if (__ratelimit(&_rs)) {
-			dev_err(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);
-			dev_err(smmu->dev,
-				"FSR    = %08x [%s%s%s%s%s%s%s%s%s], SID=0x%x\n",
-				fsr,
-				(fsr & 0x02) ? "TF " : "",
-				(fsr & 0x04) ? "AFF " : "",
-				(fsr & 0x08) ? "PF " : "",
-				(fsr & 0x10) ? "EF " : "",
-				(fsr & 0x20) ? "TLBMCF " : "",
-				(fsr & 0x40) ? "TLBLKF " : "",
-				(fsr & 0x80) ? "MHF " : "",
-				(fsr & 0x40000000) ? "SS " : "",
-				(fsr & 0x80000000) ? "MULTI " : "",
-				cbfrsynra);
+			arm_smmu_print_context_fault_info(smmu, idx, &cfi);
 
 			dev_err(smmu->dev,
 				"soft iova-to-phys=%pa\n", &phys_soft);
@@ -474,10 +454,10 @@ irqreturn_t qcom_smmu_context_fault(int irq, void *dev)
 	 */
 	if (tmp != -EBUSY) {
 		/* Clear the faulting FSR */
-		arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
+		arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, cfi.fsr);
 
 		/* Retry or terminate any stalled transactions */
-		if (fsr & ARM_SMMU_CB_FSR_SS)
+		if (cfi.fsr & ARM_SMMU_CB_FSR_SS)
 			arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_RESUME, resume);
 	}
 
diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 23cf91ac409b..79ec911ae151 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -405,32 +405,72 @@ static const struct iommu_flush_ops arm_smmu_s2_tlb_ops_v1 = {
 	.tlb_add_page	= arm_smmu_tlb_add_page_s2_v1,
 };
 
+
+void arm_smmu_read_context_fault_info(struct arm_smmu_device *smmu, int idx,
+				      struct arm_smmu_context_fault_info *cfi)
+{
+	cfi->iova = arm_smmu_cb_readq(smmu, idx, ARM_SMMU_CB_FAR);
+	cfi->fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
+	cfi->fsynr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSYNR0);
+	cfi->cbfrsynra = arm_smmu_gr1_read(smmu, ARM_SMMU_GR1_CBFRSYNRA(idx));
+}
+
+void arm_smmu_print_context_fault_info(struct arm_smmu_device *smmu, int idx,
+				       const struct arm_smmu_context_fault_info *cfi)
+{
+	dev_dbg(smmu->dev,
+		"Unhandled context fault: fsr=0x%x, iova=0x%08lx, fsynr=0x%x, cbfrsynra=0x%x, cb=%d\n",
+		cfi->fsr, cfi->iova, cfi->fsynr, cfi->cbfrsynra, idx);
+
+	dev_err(smmu->dev, "FSR    = %08x [%s%sFormat=%u%s%s%s%s%s%s%s%s], SID=0x%x\n",
+		cfi->fsr,
+		(cfi->fsr & ARM_SMMU_CB_FSR_MULTI)  ? "MULTI " : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_SS)     ? "SS " : "",
+		(u32)FIELD_GET(ARM_SMMU_CB_FSR_FORMAT, cfi->fsr),
+		(cfi->fsr & ARM_SMMU_CB_FSR_UUT)    ? " UUT" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_ASF)    ? " ASF" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_TLBLKF) ? " TLBLKF" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_TLBMCF) ? " TLBMCF" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_EF)     ? " EF" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_PF)     ? " PF" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_AFF)    ? " AFF" : "",
+		(cfi->fsr & ARM_SMMU_CB_FSR_TF)     ? " TF" : "",
+		cfi->cbfrsynra);
+
+	dev_err(smmu->dev, "FSYNR0 = %08x [S1CBNDX=%u%s%s%s%s%s%s PLVL=%u]\n",
+		cfi->fsynr,
+		(u32)FIELD_GET(ARM_SMMU_CB_FSYNR0_S1CBNDX, cfi->fsynr),
+		(cfi->fsynr & ARM_SMMU_CB_FSYNR0_AFR) ? " AFR" : "",
+		(cfi->fsynr & ARM_SMMU_CB_FSYNR0_PTWF) ? " PTWF" : "",
+		(cfi->fsynr & ARM_SMMU_CB_FSYNR0_NSATTR) ? " NSATTR" : "",
+		(cfi->fsynr & ARM_SMMU_CB_FSYNR0_IND) ? " IND" : "",
+		(cfi->fsynr & ARM_SMMU_CB_FSYNR0_PNU) ? " PNU" : "",
+		(cfi->fsynr & ARM_SMMU_CB_FSYNR0_WNR) ? " WNR" : "",
+		(u32)FIELD_GET(ARM_SMMU_CB_FSYNR0_PLVL, cfi->fsynr));
+}
+
 static irqreturn_t arm_smmu_context_fault(int irq, void *dev)
 {
-	u32 fsr, fsynr, cbfrsynra;
-	unsigned long iova;
+	struct arm_smmu_context_fault_info cfi;
 	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;
 
-	fsr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSR);
-	if (!(fsr & ARM_SMMU_CB_FSR_FAULT))
-		return IRQ_NONE;
+	arm_smmu_read_context_fault_info(smmu, idx, &cfi);
 
-	fsynr = arm_smmu_cb_read(smmu, idx, ARM_SMMU_CB_FSYNR0);
-	iova = arm_smmu_cb_readq(smmu, idx, ARM_SMMU_CB_FAR);
-	cbfrsynra = arm_smmu_gr1_read(smmu, ARM_SMMU_GR1_CBFRSYNRA(idx));
+	if (!(cfi.fsr & ARM_SMMU_CB_FSR_FAULT))
+		return IRQ_NONE;
 
-	ret = report_iommu_fault(&smmu_domain->domain, NULL, iova,
-		fsynr & ARM_SMMU_CB_FSYNR0_WNR ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ);
+	ret = report_iommu_fault(&smmu_domain->domain, NULL, cfi.iova,
+		cfi.fsynr & ARM_SMMU_CB_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))
+		arm_smmu_print_context_fault_info(smmu, idx, &cfi);
 
-	arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, fsr);
+	arm_smmu_cb_write(smmu, idx, ARM_SMMU_CB_FSR, cfi.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 b04a00126a12..e2aeb511ae90 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.h
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.h
@@ -198,6 +198,7 @@ enum arm_smmu_cbar_type {
 #define ARM_SMMU_CB_FSR			0x58
 #define ARM_SMMU_CB_FSR_MULTI		BIT(31)
 #define ARM_SMMU_CB_FSR_SS		BIT(30)
+#define ARM_SMMU_CB_FSR_FORMAT		GENMASK(10, 9)
 #define ARM_SMMU_CB_FSR_UUT		BIT(8)
 #define ARM_SMMU_CB_FSR_ASF		BIT(7)
 #define ARM_SMMU_CB_FSR_TLBLKF		BIT(6)
@@ -223,7 +224,14 @@ enum arm_smmu_cbar_type {
 #define ARM_SMMU_CB_FAR			0x60
 
 #define ARM_SMMU_CB_FSYNR0		0x68
+#define ARM_SMMU_CB_FSYNR0_PLVL		GENMASK(1, 0)
 #define ARM_SMMU_CB_FSYNR0_WNR		BIT(4)
+#define ARM_SMMU_CB_FSYNR0_PNU		BIT(5)
+#define ARM_SMMU_CB_FSYNR0_IND		BIT(6)
+#define ARM_SMMU_CB_FSYNR0_NSATTR	BIT(8)
+#define ARM_SMMU_CB_FSYNR0_PTWF		BIT(10)
+#define ARM_SMMU_CB_FSYNR0_AFR		BIT(11)
+#define ARM_SMMU_CB_FSYNR0_S1CBNDX	GENMASK(23, 16)
 
 #define ARM_SMMU_CB_FSYNR1		0x6c
 
@@ -533,4 +541,17 @@ struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu);
 void arm_smmu_write_context_bank(struct arm_smmu_device *smmu, int idx);
 int arm_mmu500_reset(struct arm_smmu_device *smmu);
 
+struct arm_smmu_context_fault_info {
+	unsigned long iova;
+	u32 fsr;
+	u32 fsynr;
+	u32 cbfrsynra;
+};
+
+void arm_smmu_read_context_fault_info(struct arm_smmu_device *smmu, int idx,
+				      struct arm_smmu_context_fault_info *cfi);
+
+void arm_smmu_print_context_fault_info(struct arm_smmu_device *smmu, int idx,
+				       const struct arm_smmu_context_fault_info *cfi);
+
 #endif /* _ARM_SMMU_H */