iommu/arm-smmu-v3: Extract reusable function __arm_smmu_cmdq_skip_err()

When SMMU_GERROR.CMDQP_ERR is different to SMMU_GERRORN.CMDQP_ERR, it
indicates that one or more errors have been encountered on a command queue
control page interface. We need to traverse all ECMDQs in that control
page to find all errors. For each ECMDQ error handling, it is much the
same as the CMDQ error handling. This common processing part is extracted
as a new function __arm_smmu_cmdq_skip_err().

Signed-off-by: Zhen Lei <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Will Deacon <[email protected]>

Author: Zhen Lei

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

@@ -359,7 +359,8 @@ static void arm_smmu_cmdq_build_sync_cmd(u64 *cmd, struct arm_smmu_device *smmu,
 	arm_smmu_cmdq_build_cmd(cmd, &ent);
 }
 
-static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
+static void __arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu,
+				     struct arm_smmu_queue *q)
 {
 	static const char * const cerror_str[] = {
 		[CMDQ_ERR_CERROR_NONE_IDX]	= "No error",
@@ -370,7 +371,6 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
 
 	int i;
 	u64 cmd[CMDQ_ENT_DWORDS];
-	struct arm_smmu_queue *q = &smmu->cmdq.q;
 	u32 cons = readl_relaxed(q->cons_reg);
 	u32 idx = FIELD_GET(CMDQ_CONS_ERR, cons);
 	struct arm_smmu_cmdq_ent cmd_sync = {
@@ -417,6 +417,11 @@ static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
 	queue_write(Q_ENT(q, cons), cmd, q->ent_dwords);
 }
 
+static void arm_smmu_cmdq_skip_err(struct arm_smmu_device *smmu)
+{
+	__arm_smmu_cmdq_skip_err(smmu, &smmu->cmdq.q);
+}
+
 /*
  * Command queue locking.
  * This is a form of bastardised rwlock with the following major changes: