It is ILLEGAL to set STE.S1STALLD if STALL_MODEL is not 0b00, which means we should not disable stall mode if stall/terminate mode is not configuable. Meanwhile, it is also ILLEGAL when STALL_MODEL==0b10 && CD.S==0 which means if stall mode is force we should always set CD.S. This patch add ARM_SMMU_FEAT_TERMINATE feature bit for smmu, and use TERMINATE feature checking to ensue above ILLEGAL cases from happening. Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx> --- drivers/iommu/arm-smmu-v3.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index dbda2eb..0745522 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -55,6 +55,7 @@ #define IDR0_STALL_MODEL_SHIFT 24 #define IDR0_STALL_MODEL_MASK 0x3 #define IDR0_STALL_MODEL_STALL (0 << IDR0_STALL_MODEL_SHIFT) +#define IDR0_STALL_MODEL_NS (1 << IDR0_STALL_MODEL_SHIFT) #define IDR0_STALL_MODEL_FORCE (2 << IDR0_STALL_MODEL_SHIFT) #define IDR0_TTENDIAN_SHIFT 21 #define IDR0_TTENDIAN_MASK 0x3 @@ -766,6 +767,7 @@ struct arm_smmu_device { #define ARM_SMMU_FEAT_SVM (1 << 15) #define ARM_SMMU_FEAT_HA (1 << 16) #define ARM_SMMU_FEAT_HD (1 << 17) +#define ARM_SMMU_FEAT_TERMINATE (1 << 18) u32 features; #define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0) @@ -1402,6 +1404,7 @@ static void arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, u64 val; bool cd_live; __u64 *cdptr = arm_smmu_get_cd_ptr(smmu_domain, ssid); + struct arm_smmu_device *smmu = smmu_domain->smmu; /* * This function handles the following cases: @@ -1468,9 +1471,11 @@ static void arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, CTXDESC_CD_0_V; /* - * FIXME: STALL_MODEL==0b10 && CD.S==0 is ILLEGAL + * STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */ - if (ssid && smmu_domain->s1_cfg.can_stall) + if ((ssid && smmu_domain->s1_cfg.can_stall) || + (!(smmu->features & ARM_SMMU_FEAT_TERMINATE) && + smmu->features & ARM_SMMU_FEAT_STALLS)) val |= CTXDESC_CD_0_S; cdptr[0] = cpu_to_le64(val); @@ -1690,12 +1695,13 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_device *smmu, u32 sid, dst[1] |= STRTAB_STE_1_PPAR; /* - * FIXME: it is illegal to set S1STALLD if STALL_MODEL=0b10 - * (force). But according to the spec, it *must* be set for + * According to spec, it is illegal to set S1STALLD if + * STALL_MODEL is not 0b00. And it *must* be set for * devices that aren't capable of stalling (notably pci!) - * So we need a "STALL_MODEL=0b00" feature bit. */ - if (smmu->features & ARM_SMMU_FEAT_STALLS && !ste->can_stall) + if (smmu->features & ARM_SMMU_FEAT_STALLS && + smmu->features & ARM_SMMU_FEAT_TERMINATE && + !ste->can_stall) dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); val |= (s1ctxptr & STRTAB_STE_0_S1CTXPTR_MASK @@ -4577,9 +4583,13 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) switch (reg & IDR0_STALL_MODEL_MASK << IDR0_STALL_MODEL_SHIFT) { case IDR0_STALL_MODEL_STALL: + smmu->features |= ARM_SMMU_FEAT_TERMINATE; /* Fallthrough */ case IDR0_STALL_MODEL_FORCE: smmu->features |= ARM_SMMU_FEAT_STALLS; + break; + case IDR0_STALL_MODEL_NS: + smmu->features |= ARM_SMMU_FEAT_TERMINATE; } if (reg & IDR0_S1P) -- 1.7.12.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html