[PATCH v5 14/18] iommu/arm-smmu-v3: Add has_ats to struct arm_smmu_cmdq_batch

[Nicolin Chen]

The arm_smmu_cmdq_batch_add_cmd_p() might flush a sub-batch mid-way, when
the ARM_SMMU_OPT_CMDQ_FORCE_SYNC is set or when a batch is full. To allow
a future change to retry these sub-batch flushes on a timeout and identify
the broken master, the batch needs to know whether it holds an ATC_INV.

Add a "has_ats" flag, set by arm_smmu_cmdq_batch_add_cmd_p() when it queues
an ATC_INV command.

No functional changes.

Assisted-by: Claude:claude-opus-4-7
Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 2 ++
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 3 +++
 2 files changed, 5 insertions(+)

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 c34be7c59ad45..56e9a94826a12 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -721,6 +721,8 @@ static inline bool arm_smmu_cmdq_supports_cmd(struct arm_smmu_cmdq *cmdq,
 struct arm_smmu_cmdq_batch {
 	struct arm_smmu_cmd		cmds[CMDQ_BATCH_ENTRIES];
 	struct arm_smmu_cmdq		*cmdq;
+	/* Set when an ATC_INV is queued; gates the retry-aware sync decision */
+	bool				has_ats;
 	int				num;
 };
 
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 e2fa9d27c6586..78e2559bdc491 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -917,6 +917,7 @@ static void arm_smmu_cmdq_batch_init_cmd(struct arm_smmu_device *smmu,
 {
 	cmds->num = 0;
 	cmds->cmdq = arm_smmu_get_cmdq(smmu, cmd);
+	cmds->has_ats = false;
 }
 
 static int arm_smmu_cmdq_batch_issue(struct arm_smmu_device *smmu,
@@ -946,6 +947,8 @@ static void arm_smmu_cmdq_batch_add_cmd_p(struct arm_smmu_device *smmu,
 		arm_smmu_cmdq_batch_init_cmd(smmu, cmds, cmd);
 	}
 
+	if (FIELD_GET(CMDQ_0_OP, cmd->data[0]) == CMDQ_OP_ATC_INV)
+		cmds->has_ats = true;
 	cmds->cmds[cmds->num++] = *cmd;
 }
 
-- 
2.43.0