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| author | Yisheng Xie <xieyisheng1@huawei.com> | 2017-09-21 15:36:07 +0300 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2017-10-20 18:55:04 +0300 |
| commit | 9cff86fd2b960f9bedc67771c24a73d7dc32048d (patch) | |
| tree | 4e53fee65a0f6215f89f2124d083da0471d0757c /drivers/iommu/arm-smmu-v3.c | |
| parent | 74f55d34414c866dbf3a69e28a2f963abe61ca58 (diff) | |
| download | linux-9cff86fd2b960f9bedc67771c24a73d7dc32048d.tar.xz | |
iommu/arm-smmu-v3: Avoid ILLEGAL setting of STE.S1STALLD and CD.S
According to Spec, it is ILLEGAL to set STE.S1STALLD if STALL_MODEL
is not 0b00, which means we should not disable stall mode if stall
or 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.
As Jean-Philippe's suggestion, this patch introduce a feature bit
ARM_SMMU_FEAT_STALL_FORCE, which means smmu only supports stall force.
Therefore, we can avoid the ILLEGAL setting of STE.S1STALLD.by checking
ARM_SMMU_FEAT_STALL_FORCE.
This patch keeps the ARM_SMMU_FEAT_STALLS as the meaning of stall supported
(force or configuable) to easy to expand the future function, i.e. we can
only use ARM_SMMU_FEAT_STALLS to check whether we should register fault
handle or enable master can_stall, etc to supporte platform SVM.
The feature bit, STE.S1STALLD and CD.S setting will be like:
STALL_MODEL FEATURE S1STALLD CD.S
0b00 ARM_SMMU_FEAT_STALLS 0b1 0b0
0b01 !ARM_SMMU_FEAT_STALLS && !ARM_SMMU_FEAT_STALL_FORCE 0b0 0b0
0b10 ARM_SMMU_FEAT_STALLS && ARM_SMMU_FEAT_STALL_FORCE 0b0 0b1
after apply this patch.
Signed-off-by: Yisheng Xie <xieyisheng1@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/iommu/arm-smmu-v3.c')
| -rw-r--r-- | drivers/iommu/arm-smmu-v3.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 80532d9ecaaf..159117e2c5ad 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -316,6 +316,7 @@ #define ARM64_TCR_TBI0_MASK 0x1UL #define CTXDESC_CD_0_AA64 (1UL << 41) +#define CTXDESC_CD_0_S (1UL << 44) #define CTXDESC_CD_0_R (1UL << 45) #define CTXDESC_CD_0_A (1UL << 46) #define CTXDESC_CD_0_ASET_SHIFT 47 @@ -595,6 +596,7 @@ struct arm_smmu_device { #define ARM_SMMU_FEAT_TRANS_S2 (1 << 10) #define ARM_SMMU_FEAT_STALLS (1 << 11) #define ARM_SMMU_FEAT_HYP (1 << 12) +#define ARM_SMMU_FEAT_STALL_FORCE (1 << 13) u32 features; #define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0) @@ -987,6 +989,11 @@ static void arm_smmu_write_ctx_desc(struct arm_smmu_device *smmu, CTXDESC_CD_0_R | CTXDESC_CD_0_A | CTXDESC_CD_0_ASET_PRIVATE | CTXDESC_CD_0_AA64 | (u64)cfg->cd.asid << CTXDESC_CD_0_ASID_SHIFT | CTXDESC_CD_0_V; + + /* STALL_MODEL==0b10 && CD.S==0 is ILLEGAL */ + if (smmu->features & ARM_SMMU_FEAT_STALL_FORCE) + val |= CTXDESC_CD_0_S; + cfg->cdptr[0] = cpu_to_le64(val); val = cfg->cd.ttbr & CTXDESC_CD_1_TTB0_MASK << CTXDESC_CD_1_TTB0_SHIFT; @@ -1107,7 +1114,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_device *smmu, u32 sid, #endif STRTAB_STE_1_STRW_NSEL1 << STRTAB_STE_1_STRW_SHIFT); - if (smmu->features & ARM_SMMU_FEAT_STALLS) + if (smmu->features & ARM_SMMU_FEAT_STALLS && + !(smmu->features & ARM_SMMU_FEAT_STALL_FORCE)) dst[1] |= cpu_to_le64(STRTAB_STE_1_S1STALLD); val |= (ste->s1_cfg->cdptr_dma & STRTAB_STE_0_S1CTXPTR_MASK @@ -2531,9 +2539,10 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) coherent ? "true" : "false"); switch (reg & IDR0_STALL_MODEL_MASK << IDR0_STALL_MODEL_SHIFT) { - case IDR0_STALL_MODEL_STALL: - /* Fallthrough */ case IDR0_STALL_MODEL_FORCE: + smmu->features |= ARM_SMMU_FEAT_STALL_FORCE; + /* Fallthrough */ + case IDR0_STALL_MODEL_STALL: smmu->features |= ARM_SMMU_FEAT_STALLS; } |