[PATCH v3 1/5] iommu/arm-smmu-v3: Add CS_NONE quirk

Nicolin Chen nicolinc at nvidia.com
Thu Nov 18 23:19:55 PST 2021


The CMDQV extension in NVIDIA Grace SoC only supports CS_NONE in the
CS field of CMD_SYNC. So this patch adds a quirk flag to accommodate
that.

Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 7 ++++++-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 4 ++++
 2 files changed, 10 insertions(+), 1 deletion(-)

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 f5848b351b19..e6fee69dd79c 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -319,7 +319,9 @@ static int arm_smmu_cmdq_build_cmd(u64 *cmd, struct arm_smmu_cmdq_ent *ent)
 		cmd[1] |= FIELD_PREP(CMDQ_RESUME_1_STAG, ent->resume.stag);
 		break;
 	case CMDQ_OP_CMD_SYNC:
-		if (ent->sync.msiaddr) {
+		if (ent->sync.cs_none) {
+			cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_NONE);
+		} else if (ent->sync.msiaddr) {
 			cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_IRQ);
 			cmd[1] |= ent->sync.msiaddr & CMDQ_SYNC_1_MSIADDR_MASK;
 		} else {
@@ -356,6 +358,9 @@ static void arm_smmu_cmdq_build_sync_cmd(u64 *cmd, struct arm_smmu_device *smmu,
 				   q->ent_dwords * 8;
 	}
 
+	if (q->quirks & CMDQ_QUIRK_SYNC_CS_NONE_ONLY)
+		ent.sync.cs_none = true;
+
 	arm_smmu_cmdq_build_cmd(cmd, &ent);
 }
 
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 4cb136f07914..7a6a6045700d 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -499,6 +499,7 @@ struct arm_smmu_cmdq_ent {
 		#define CMDQ_OP_CMD_SYNC	0x46
 		struct {
 			u64			msiaddr;
+			bool			cs_none;
 		} sync;
 	};
 };
@@ -531,6 +532,9 @@ struct arm_smmu_queue {
 
 	u32 __iomem			*prod_reg;
 	u32 __iomem			*cons_reg;
+
+#define CMDQ_QUIRK_SYNC_CS_NONE_ONLY	BIT(0)	/* CMD_SYNC CS field supports CS_NONE only */
+	u32				quirks;
 };
 
 struct arm_smmu_queue_poll {
-- 
2.17.1




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