From a529ea19aadb7a3bbcce3335ed4671adbe275b22 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 19 Oct 2017 16:49:30 +0100 Subject: iommu/arm-smmu-v3: Consolidate identical timeouts We have separate (identical) timeout values for polling for a queue to drain and waiting for an MSI to signal CMD_SYNC completion. In reality, we only wait for the command queue to drain if we're waiting on a sync, so just merged these two timeouts into a single constant. Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu-v3.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 3876a0328589..c148f76dd8e2 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -418,8 +418,7 @@ /* High-level queue structures */ #define ARM_SMMU_POLL_TIMEOUT_US 100 -#define ARM_SMMU_CMDQ_DRAIN_TIMEOUT_US 1000000 /* 1s! */ -#define ARM_SMMU_SYNC_TIMEOUT_US 1000000 /* 1s! */ +#define ARM_SMMU_CMDQ_SYNC_TIMEOUT_US 1000000 /* 1s! */ #define MSI_IOVA_BASE 0x8000000 #define MSI_IOVA_LENGTH 0x100000 @@ -767,17 +766,17 @@ static void queue_inc_prod(struct arm_smmu_queue *q) * Wait for the SMMU to consume items. If drain is true, wait until the queue * is empty. Otherwise, wait until there is at least one free slot. */ -static int queue_poll_cons(struct arm_smmu_queue *q, bool drain, bool wfe) +static int queue_poll_cons(struct arm_smmu_queue *q, bool sync, bool wfe) { ktime_t timeout; unsigned int delay = 1; - /* Wait longer if it's queue drain */ - timeout = ktime_add_us(ktime_get(), drain ? - ARM_SMMU_CMDQ_DRAIN_TIMEOUT_US : + /* Wait longer if it's a CMD_SYNC */ + timeout = ktime_add_us(ktime_get(), sync ? + ARM_SMMU_CMDQ_SYNC_TIMEOUT_US : ARM_SMMU_POLL_TIMEOUT_US); - while (queue_sync_cons(q), (drain ? !queue_empty(q) : queue_full(q))) { + while (queue_sync_cons(q), (sync ? !queue_empty(q) : queue_full(q))) { if (ktime_compare(ktime_get(), timeout) > 0) return -ETIMEDOUT; @@ -986,10 +985,13 @@ static void arm_smmu_cmdq_issue_cmd(struct arm_smmu_device *smmu, */ static int __arm_smmu_sync_poll_msi(struct arm_smmu_device *smmu, u32 sync_idx) { - ktime_t timeout = ktime_add_us(ktime_get(), ARM_SMMU_SYNC_TIMEOUT_US); - u32 val = smp_cond_load_acquire(&smmu->sync_count, - (int)(VAL - sync_idx) >= 0 || - !ktime_before(ktime_get(), timeout)); + ktime_t timeout; + u32 val; + + timeout = ktime_add_us(ktime_get(), ARM_SMMU_CMDQ_SYNC_TIMEOUT_US); + val = smp_cond_load_acquire(&smmu->sync_count, + (int)(VAL - sync_idx) >= 0 || + !ktime_before(ktime_get(), timeout)); return (int)(val - sync_idx) < 0 ? -ETIMEDOUT : 0; } -- cgit