When nested stage translation is setup, both s1_cfg and s2_cfg are set. We introduce a new smmu_domain abort field that will be set upon guest stage1 configuration passing. If no guest stage1 config has been attached, it is ignored when writing the STE. arm_smmu_write_strtab_ent() is modified to write both stage fields in the STE and deal with the abort field. In nested mode, only stage 2 is "finalized" as the host does not own/configure the stage 1 context descriptor; guest does. Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx> --- v13 -> v14: - removed BUG_ON(ste_live && !nested) as this should never happen - restored the old comment as there is always an abort in between S2 -> S1 + S2 and S1 + S2 -> S2 - remove sparse warning v10 -> v11: - Fix an issue reported by Shameer when switching from with vSMMU to without vSMMU. Despite the spec does not seem to mention it seems to be needed to reset the 2 high 64b when switching from S1+S2 cfg to S1 only. Especially dst[3] needs to be reset (S2TTB). On some implementations, if the S2TTB is not reset, this causes a C_BAD_STE error --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 55 ++++++++++++++++++--- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 2 + 2 files changed, 49 insertions(+), 8 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 14e5666c25dc..085a784dfaee 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -1237,7 +1237,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, * 3. Update Config, sync */ u64 val = le64_to_cpu(dst[0]); - bool ste_live = false; + bool s1_live = false, s2_live = false, ste_live; + bool abort, translate = false; struct arm_smmu_device *smmu = NULL; struct arm_smmu_s1_cfg *s1_cfg; struct arm_smmu_s2_cfg *s2_cfg; @@ -1277,6 +1278,7 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, default: break; } + translate = s1_cfg->set || s2_cfg->set; } if (val & STRTAB_STE_0_V) { @@ -1284,23 +1286,36 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, case STRTAB_STE_0_CFG_BYPASS: break; case STRTAB_STE_0_CFG_S1_TRANS: + s1_live = true; + break; case STRTAB_STE_0_CFG_S2_TRANS: - ste_live = true; + s2_live = true; + break; + case STRTAB_STE_0_CFG_NESTED: + s1_live = true; + s2_live = true; break; case STRTAB_STE_0_CFG_ABORT: - BUG_ON(!disable_bypass); break; default: BUG(); /* STE corruption */ } } + ste_live = s1_live || s2_live; + /* Nuke the existing STE_0 value, as we're going to rewrite it */ val = STRTAB_STE_0_V; /* Bypass/fault */ - if (!smmu_domain || !(s1_cfg->set || s2_cfg->set)) { - if (!smmu_domain && disable_bypass) + + if (!smmu_domain) + abort = disable_bypass; + else + abort = smmu_domain->abort; + + if (abort || !translate) { + if (abort) val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_ABORT); else val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_BYPASS); @@ -1318,11 +1333,17 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, return; } + if (ste_live) { + /* First invalidate the live STE */ + dst[0] = cpu_to_le64(STRTAB_STE_0_CFG_ABORT); + arm_smmu_sync_ste_for_sid(smmu, sid); + } + if (s1_cfg->set) { u64 strw = smmu->features & ARM_SMMU_FEAT_E2H ? STRTAB_STE_1_STRW_EL2 : STRTAB_STE_1_STRW_NSEL1; - BUG_ON(ste_live); + BUG_ON(s1_live); dst[1] = cpu_to_le64( FIELD_PREP(STRTAB_STE_1_S1DSS, STRTAB_STE_1_S1DSS_SSID0) | FIELD_PREP(STRTAB_STE_1_S1CIR, STRTAB_STE_1_S1C_CACHE_WBRA) | @@ -1341,7 +1362,14 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, } if (s2_cfg->set) { - BUG_ON(ste_live); + u64 vttbr = s2_cfg->vttbr & STRTAB_STE_3_S2TTB_MASK; + + if (s2_live) { + u64 s2ttb = le64_to_cpu(dst[3]) & STRTAB_STE_3_S2TTB_MASK; + + BUG_ON(s2ttb != vttbr); + } + dst[2] = cpu_to_le64( FIELD_PREP(STRTAB_STE_2_S2VMID, s2_cfg->vmid) | FIELD_PREP(STRTAB_STE_2_VTCR, s2_cfg->vtcr) | @@ -1351,9 +1379,12 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_master *master, u32 sid, STRTAB_STE_2_S2PTW | STRTAB_STE_2_S2AA64 | STRTAB_STE_2_S2R); - dst[3] = cpu_to_le64(s2_cfg->vttbr & STRTAB_STE_3_S2TTB_MASK); + dst[3] = cpu_to_le64(vttbr); val |= FIELD_PREP(STRTAB_STE_0_CFG, STRTAB_STE_0_CFG_S2_TRANS); + } else { + dst[2] = 0; + dst[3] = 0; } if (master->ats_enabled) @@ -2154,6 +2185,14 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain, return 0; } + if (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED && + (!(smmu->features & ARM_SMMU_FEAT_TRANS_S1) || + !(smmu->features & ARM_SMMU_FEAT_TRANS_S2))) { + dev_info(smmu_domain->smmu->dev, + "does not implement two stages\n"); + return -EINVAL; + } + /* Restrict the stage to what we can actually support */ if (!(smmu->features & ARM_SMMU_FEAT_TRANS_S1)) smmu_domain->stage = ARM_SMMU_DOMAIN_S2; diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index ec2b77596b6a..eb0cc08e8240 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -206,6 +206,7 @@ #define STRTAB_STE_0_CFG_BYPASS 4 #define STRTAB_STE_0_CFG_S1_TRANS 5 #define STRTAB_STE_0_CFG_S2_TRANS 6 +#define STRTAB_STE_0_CFG_NESTED 7 #define STRTAB_STE_0_S1FMT GENMASK_ULL(5, 4) #define STRTAB_STE_0_S1FMT_LINEAR 0 @@ -722,6 +723,7 @@ struct arm_smmu_domain { enum arm_smmu_domain_stage stage; struct arm_smmu_s1_cfg s1_cfg; struct arm_smmu_s2_cfg s2_cfg; + bool abort; struct iommu_domain domain; -- 2.26.2