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Add a helper function that waits till the cmdq is empty using `queue_empty`. Signed-off-by: Pranjal Shrivastava --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 24 +++++++++++++++++++++ 1 file changed, 24 insertions(+) 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 80362d9f293b..f65d9bca0392 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -754,6 +754,30 @@ static int arm_smmu_cmdq_poll_until_sync(struct arm_smmu_device *smmu, return __arm_smmu_cmdq_poll_until_consumed(smmu, cmdq, llq); } +/* + * Wait until the SMMU cmdq is empty + * Must be called with the cmdq lock held in some capacity. + */ +static int arm_smmu_cmdq_poll_until_empty(struct arm_smmu_device *smmu, + struct arm_smmu_cmdq *cmdq, + struct arm_smmu_ll_queue *llq) +{ + struct arm_smmu_queue_poll qp; + int ret = 0; + + queue_poll_init(smmu, &qp); + llq->val = READ_ONCE(cmdq->q.llq.val); + do { + if (queue_empty(llq)) + break; + + ret = queue_poll(&qp); + llq->cons = readl(cmdq->q.cons_reg); + } while (!ret); + + return ret; +} + static void arm_smmu_cmdq_write_entries(struct arm_smmu_cmdq *cmdq, u64 *cmds, u32 prod, int n) { -- 2.49.0.rc1.451.g8f38331e32-goog