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iommu/arm-smmu: set CBARn.BPSHCFG to NSH for s1-s2-bypass contexts

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Whilst trying to bring-up an SMMUv2 implementation with the table
walker plumbed into a coherent interconnect, I noticed that the memory
transactions targetting the CPU caches from the SMMU were marked as
outer-shareable instead of inner-shareable.

After a bunch of digging, it seems that we actually need to program
CBARn.BPSHCFG for s1-s2-bypass contexts to act as non-shareable in order
for the shareability configured in the corresponding TTBCR not to be
overridden with an outer-shareable attribute.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Will Deacon 2014-02-06 14:59:05 +00:00
parent 6dd35f45b8
commit 57ca90f680
1 changed files with 12 additions and 4 deletions
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16
drivers/iommu/arm-smmu.c
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@ -190,6 +190,9 @@
#define ARM_SMMU_GR1_CBAR(n) (0x0 + ((n) << 2)) #define ARM_SMMU_GR1_CBAR(n) (0x0 + ((n) << 2))
#define CBAR_VMID_SHIFT 0 #define CBAR_VMID_SHIFT 0
#define CBAR_VMID_MASK 0xff #define CBAR_VMID_MASK 0xff
#define CBAR_S1_BPSHCFG_SHIFT 8
#define CBAR_S1_BPSHCFG_MASK 3
#define CBAR_S1_BPSHCFG_NSH 3
#define CBAR_S1_MEMATTR_SHIFT 12 #define CBAR_S1_MEMATTR_SHIFT 12
#define CBAR_S1_MEMATTR_MASK 0xf #define CBAR_S1_MEMATTR_MASK 0xf
#define CBAR_S1_MEMATTR_WB 0xf #define CBAR_S1_MEMATTR_WB 0xf
@ -671,11 +674,16 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
if (smmu->version == 1) if (smmu->version == 1)
reg |= root_cfg->irptndx << CBAR_IRPTNDX_SHIFT; reg |= root_cfg->irptndx << CBAR_IRPTNDX_SHIFT;
/* Use the weakest memory type, so it is overridden by the pte */ /*
if (stage1) * Use the weakest shareability/memory types, so they are
reg |= (CBAR_S1_MEMATTR_WB << CBAR_S1_MEMATTR_SHIFT); * overridden by the ttbcr/pte.
else */
if (stage1) {
reg |= (CBAR_S1_BPSHCFG_NSH << CBAR_S1_BPSHCFG_SHIFT) |
(CBAR_S1_MEMATTR_WB << CBAR_S1_MEMATTR_SHIFT);
} else {
reg |= ARM_SMMU_CB_VMID(root_cfg) << CBAR_VMID_SHIFT; reg |= ARM_SMMU_CB_VMID(root_cfg) << CBAR_VMID_SHIFT;
}
writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(root_cfg->cbndx)); writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(root_cfg->cbndx));
if (smmu->version > 1) { if (smmu->version > 1) {