evie/android_kernel_oneplus_msm8998
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iommu: disable smmu stalls on faulty transactions

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Disable the SMMU stalls on faulty transactions by terminating it using
the CB.SCTLR register. Faulty transaction on a CB causes the back
pressure on the QSMMU transaction pipe which inturn affect the other
masters using the same SMMU. Pass the DOMAIN_ATTR_CB_STALL_DISABLE flag
to iommu_domain_set_attr api in order to use this feature.

Change-Id: Ib8fa35854ff24e0295d330c5fb79375f58c3e841
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
This commit is contained in:
Charan Teja Reddy 2017-04-20 19:11:20 +05:30 • committed by Gerrit - the friendly Code Review server
parent 048c70075f
commit ad3b1dcc93
3 changed files with 20 additions and 1 deletions
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18
drivers/iommu/arm-smmu.c
View file

@ -234,6 +234,7 @@
#define SCTLR_S1_ASIDPNE (1 << 12)
#define SCTLR_CFCFG (1 << 7)
#define SCTLR_HUPCF (1 << 8)
#define SCTLR_CFIE (1 << 6)
#define SCTLR_CFRE (1 << 5)
#define SCTLR_E (1 << 4)
@ -1628,6 +1629,11 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
/* SCTLR */
reg = SCTLR_CFCFG | SCTLR_CFIE | SCTLR_CFRE | SCTLR_EAE_SBOP;
if (smmu_domain->attributes & (1 << DOMAIN_ATTR_CB_STALL_DISABLE)) {
reg &= ~SCTLR_CFCFG;
reg |= SCTLR_HUPCF;
}
if ((!(smmu_domain->attributes & (1 << DOMAIN_ATTR_S1_BYPASS)) &&
!(smmu_domain->attributes & (1 << DOMAIN_ATTR_EARLY_MAP))) ||
!stage1)
@ -3138,7 +3144,11 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
& (1 << DOMAIN_ATTR_ENABLE_TTBR1));
ret = 0;
break;
case DOMAIN_ATTR_CB_STALL_DISABLE:
*((int *)data) = !!(smmu_domain->attributes
& (1 << DOMAIN_ATTR_CB_STALL_DISABLE));
ret = 0;
break;
default:
ret = -ENODEV;
break;
@ -3325,6 +3335,12 @@ static int arm_smmu_domain_set_attr(struct iommu_domain *domain,
ret = 0;
break;
}
case DOMAIN_ATTR_CB_STALL_DISABLE:
if (*((int *)data))
smmu_domain->attributes |=
1 << DOMAIN_ATTR_CB_STALL_DISABLE;
ret = 0;
break;
default:
ret = -ENODEV;
break;

2
drivers/iommu/iommu-debug.c
View file

@ -72,6 +72,8 @@ static const char *iommu_debug_attr_to_string(enum iommu_attr attr)
return "DOMAIN_ATTR_FAST";
case DOMAIN_ATTR_EARLY_MAP:
return "DOMAIN_ATTR_EARLY_MAP";
case DOMAIN_ATTR_CB_STALL_DISABLE:
return "DOMAIN_ATTR_CB_STALL_DISABLE";
default:
return "Unknown attr!";
}

1
include/linux/iommu.h
View file

@ -137,6 +137,7 @@ enum iommu_attr {
DOMAIN_ATTR_PAGE_TABLE_IS_COHERENT,
DOMAIN_ATTR_PAGE_TABLE_FORCE_COHERENT,
DOMAIN_ATTR_ENABLE_TTBR1,
DOMAIN_ATTR_CB_STALL_DISABLE,
DOMAIN_ATTR_MAX,
};