[PATCH v8 4/6] iommu/arm-smmu-v3: Add CS_NONE quirk for CONFIG_TEGRA241_CMDQV

[Nicolin Chen]

The CMDQV extension in NVIDIA Tegra241 SoC only supports CS_NONE in the
CS field of CMD_SYNC. Add a quirk flag to accommodate that.

Reviewed-by: Jason Gunthorpe <jgg at nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 +++++++-
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 +++
 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 c864c634cd23..ba0e24d5ffbf 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -345,6 +345,11 @@ static void arm_smmu_cmdq_build_sync_cmd(u64 *cmd, struct arm_smmu_device *smmu,
 		 FIELD_PREP(CMDQ_SYNC_0_MSH, ARM_SMMU_SH_ISH) |
 		 FIELD_PREP(CMDQ_SYNC_0_MSIATTR, ARM_SMMU_MEMATTR_OIWB);
 
+	if (q->quirks & CMDQ_QUIRK_SYNC_CS_NONE_ONLY) {
+		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_NONE);
+		return;
+	}
+
 	if (!(smmu->options & ARM_SMMU_OPT_MSIPOLL)) {
 		cmd[0] |= FIELD_PREP(CMDQ_SYNC_0_CS, CMDQ_SYNC_0_CS_SEV);
 		return;
@@ -690,7 +695,8 @@ static int arm_smmu_cmdq_poll_until_sync(struct arm_smmu_device *smmu,
 					 struct arm_smmu_cmdq *cmdq,
 					 struct arm_smmu_ll_queue *llq)
 {
-	if (smmu->options & ARM_SMMU_OPT_MSIPOLL)
+	if (smmu->options & ARM_SMMU_OPT_MSIPOLL &&
+	    !(cmdq->q.quirks & CMDQ_QUIRK_SYNC_CS_NONE_ONLY))
 		return __arm_smmu_cmdq_poll_until_msi(smmu, cmdq, llq);
 
 	return __arm_smmu_cmdq_poll_until_consumed(smmu, cmdq, llq);
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 180c0b1e0658..01227c0de290 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -543,6 +543,9 @@ 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 {
-- 
2.43.0