[PATCH 2/3] iommu/arm-smmu-v3: Make BTM optional for SVA

[Jean-Philippe Brucker]

When BTM isn't supported by the SMMU, send invalidations on the
command queue.

Signed-off-by: Jean-Philippe Brucker <jean-philippe at linaro.org>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h     |  3 +++
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 14 +++++++++++---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c     | 14 ++++++++++++++
 3 files changed, 28 insertions(+), 3 deletions(-)

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 a6536c2b32d0..652d03ad8ae6 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -743,6 +743,9 @@ extern struct arm_smmu_ctx_desc quiet_cd;
 int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, int ssid,
 			    struct arm_smmu_ctx_desc *cd);
 void arm_smmu_tlb_inv_asid(struct arm_smmu_device *smmu, u16 asid);
+void arm_smmu_tlb_inv_range_asid(unsigned long iova, size_t size, int asid,
+				 size_t granule, bool leaf,
+				 struct arm_smmu_domain *smmu_domain);
 bool arm_smmu_free_asid(struct arm_smmu_ctx_desc *cd);
 int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain, int ssid,
 			    unsigned long iova, size_t size);
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
index 642ce2c225b5..ad8cf62a8f83 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c
@@ -16,6 +16,7 @@ struct arm_smmu_mmu_notifier {
 	struct mmu_notifier		mn;
 	struct arm_smmu_ctx_desc	*cd;
 	bool				cleared;
+	bool				tlb_inv_command;
 	refcount_t			refs;
 	struct list_head		list;
 	struct arm_smmu_domain		*domain;
@@ -182,9 +183,13 @@ static void arm_smmu_mm_invalidate_range(struct mmu_notifier *mn,
 					 unsigned long start, unsigned long end)
 {
 	struct arm_smmu_mmu_notifier *smmu_mn = mn_to_smmu(mn);
+	struct arm_smmu_domain *smmu_domain = smmu_mn->domain;
+	size_t size = end - start + 1;
 
-	arm_smmu_atc_inv_domain(smmu_mn->domain, mm->pasid, start,
-				end - start + 1);
+	if (smmu_mn->tlb_inv_command)
+		arm_smmu_tlb_inv_range_asid(start, size, smmu_mn->cd->asid,
+					    PAGE_SIZE, false, smmu_domain);
+	arm_smmu_atc_inv_domain(smmu_domain, mm->pasid, start, size);
 }
 
 static void arm_smmu_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
@@ -253,6 +258,9 @@ arm_smmu_mmu_notifier_get(struct arm_smmu_domain *smmu_domain,
 	smmu_mn->domain = smmu_domain;
 	smmu_mn->mn.ops = &arm_smmu_mmu_notifier_ops;
 
+	if (!(smmu_domain->smmu->features & ARM_SMMU_FEAT_BTM))
+		smmu_mn->tlb_inv_command = true;
+
 	ret = mmu_notifier_register(&smmu_mn->mn, mm);
 	if (ret) {
 		kfree(smmu_mn);
@@ -404,7 +412,7 @@ bool arm_smmu_sva_supported(struct arm_smmu_device *smmu)
 	unsigned long reg, fld;
 	unsigned long oas;
 	unsigned long asid_bits;
-	u32 feat_mask = ARM_SMMU_FEAT_BTM | ARM_SMMU_FEAT_COHERENCY;
+	u32 feat_mask = ARM_SMMU_FEAT_COHERENCY;
 
 	if (vabits_actual == 52)
 		feat_mask |= ARM_SMMU_FEAT_VAX;
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 a27b074d5c0c..db545834493b 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2018,6 +2018,20 @@ static void arm_smmu_tlb_inv_range_domain(unsigned long iova, size_t size,
 	arm_smmu_atc_inv_domain(smmu_domain, 0, iova, size);
 }
 
+void arm_smmu_tlb_inv_range_asid(unsigned long iova, size_t size, int asid,
+				 size_t granule, bool leaf,
+				 struct arm_smmu_domain *smmu_domain)
+{
+	struct arm_smmu_cmdq_ent cmd = {
+		.opcode	= CMDQ_OP_TLBI_NH_VA,
+		.tlbi = {
+			.asid	= asid,
+			.leaf	= leaf,
+		},
+	};
+	arm_smmu_tlb_inv_range(&cmd, iova, size, granule, smmu_domain);
+}
+
 static void arm_smmu_tlb_inv_page_nosync(struct iommu_iotlb_gather *gather,
 					 unsigned long iova, size_t granule,
 					 void *cookie)
-- 
2.30.0