Bits[15:0] in CBFRSYNRA register contain information about StreamID of the incoming transaction that generated the fault. Dump CBFRSYNRA register to get this info. This is specially useful in a distributed SMMU architecture where multiple masters are connected to the SMMU. SID information helps to quickly identify the faulting master device. Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx> --- V1 of the patch available @ https://lore.kernel.org/patchwork/patch/1061615/ Changes from v1: - Dump the raw register value of CBFRSYNRA register in the context fault log rather than extracting the SID inforamtion and dumping that. drivers/iommu/arm-smmu-regs.h | 2 ++ drivers/iommu/arm-smmu.c | 8 ++++++-- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm-smmu-regs.h b/drivers/iommu/arm-smmu-regs.h index a1226e4ab5f8..e9132a926761 100644 --- a/drivers/iommu/arm-smmu-regs.h +++ b/drivers/iommu/arm-smmu-regs.h @@ -147,6 +147,8 @@ enum arm_smmu_s2cr_privcfg { #define CBAR_IRPTNDX_SHIFT 24 #define CBAR_IRPTNDX_MASK 0xff +#define ARM_SMMU_GR1_CBFRSYNRA(n) (0x400 + ((n) << 2)) + #define ARM_SMMU_GR1_CBA2R(n) (0x800 + ((n) << 2)) #define CBA2R_RW64_32BIT (0 << 0) #define CBA2R_RW64_64BIT (1 << 0) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 045d93884164..a4773e8c6b0e 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -575,7 +575,9 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev) struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); struct arm_smmu_cfg *cfg = &smmu_domain->cfg; struct arm_smmu_device *smmu = smmu_domain->smmu; + void __iomem *gr1_base = ARM_SMMU_GR1(smmu); void __iomem *cb_base; + u32 cbfrsynra; cb_base = ARM_SMMU_CB(smmu, cfg->cbndx); fsr = readl_relaxed(cb_base + ARM_SMMU_CB_FSR); @@ -585,10 +587,12 @@ static irqreturn_t arm_smmu_context_fault(int irq, void *dev) fsynr = readl_relaxed(cb_base + ARM_SMMU_CB_FSYNR0); iova = readq_relaxed(cb_base + ARM_SMMU_CB_FAR); + cbfrsynra = readl_relaxed(gr1_base + + ARM_SMMU_GR1_CBFRSYNRA(cfg->cbndx)); dev_err_ratelimited(smmu->dev, - "Unhandled context fault: fsr=0x%x, iova=0x%08lx, fsynr=0x%x, cb=%d\n", - fsr, iova, fsynr, cfg->cbndx); + "Unhandled context fault: fsr=0x%x, iova=0x%08lx, fsynr=0x%x, cbfrsynra = 0x%x, cb=%d\n", + fsr, iova, fsynr, cbfrsynra, cfg->cbndx); writel(fsr, cb_base + ARM_SMMU_CB_FSR); return IRQ_HANDLED; -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation