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iommu/arm-smmu-v3: Consolidate identical timeouts

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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 <will.deacon@arm.com>
This commit is contained in:
Will Deacon 2017-10-19 16:49:30 +01:00
parent 49806599c3
commit a529ea19aa
1 changed files with 13 additions and 11 deletions
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24
drivers/iommu/arm-smmu-v3.c
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@ -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;
}