[PATCH v2 3/3] iommu/arm-smmu: Add support for DOMAIN_ATTR_SPLIT_TABLES

[Jordan Crouse]

When DOMAIN_ATTR_SPLIT_TABLES is specified for pass ARM_64_LPAE_SPLIT_S1
to io_pgtable_ops to allocate and initialize TTBR0 and TTBR1 pagetables.

v3: Moved all the pagetable specific work into io-pgtable-arm in a previous
patch.

Signed-off-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>
---

 drivers/iommu/arm-smmu.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 653b6b3..7a6b4bb 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -257,6 +257,7 @@ struct arm_smmu_domain {
 	bool				non_strict;
 	struct mutex			init_mutex; /* Protects smmu pointer */
 	spinlock_t			cb_lock; /* Serialises ATS1* ops and TLB syncs */
+	u32 attributes;
 	struct iommu_domain		domain;
 };
 
@@ -832,7 +833,11 @@ static int arm_smmu_init_domain_context(struct iommu_domain *domain,
 		ias = smmu->va_size;
 		oas = smmu->ipa_size;
 		if (cfg->fmt == ARM_SMMU_CTX_FMT_AARCH64) {
-			fmt = ARM_64_LPAE_S1;
+			if (smmu_domain->attributes &
+				(1 << DOMAIN_ATTR_SPLIT_TABLES))
+				fmt = ARM_64_LPAE_SPLIT_S1;
+			else
+				fmt = ARM_64_LPAE_S1;
 		} else if (cfg->fmt == ARM_SMMU_CTX_FMT_AARCH32_L) {
 			fmt = ARM_32_LPAE_S1;
 			ias = min(ias, 32UL);
@@ -1582,6 +1587,10 @@ static int arm_smmu_domain_get_attr(struct iommu_domain *domain,
 		case DOMAIN_ATTR_NESTING:
 			*(int *)data = (smmu_domain->stage == ARM_SMMU_DOMAIN_NESTED);
 			return 0;
+		case DOMAIN_ATTR_SPLIT_TABLES:
+			*(int *)data = !!(smmu_domain->attributes &
+				(1 << DOMAIN_ATTR_SPLIT_TABLES));
+			return 0;
 		default:
 			return -ENODEV;
 		}
@@ -1622,6 +1631,11 @@ static int arm_smmu_domain_set_attr(struct iommu_domain *domain,
 			else
 				smmu_domain->stage = ARM_SMMU_DOMAIN_S1;
 			break;
+		case DOMAIN_ATTR_SPLIT_TABLES:
+			if (*((int *)data))
+				smmu_domain->attributes |=
+					(1 << DOMAIN_ATTR_SPLIT_TABLES);
+			break;
 		default:
 			ret = -ENODEV;
 		}
-- 
2.7.4