/* High-level queue structures */
#define ARM_SMMU_POLL_TIMEOUT_US 100
#define ARM_SMMU_CMDQ_SYNC_TIMEOUT_US 1000000 /* 1s! */
+#define ARM_SMMU_CMDQ_SYNC_SPIN_COUNT 10
#define MSI_IOVA_BASE 0x8000000
#define MSI_IOVA_LENGTH 0x100000
static int queue_poll_cons(struct arm_smmu_queue *q, bool sync, bool wfe)
{
ktime_t timeout;
- unsigned int delay = 1;
+ unsigned int delay = 1, spin_cnt = 0;
/* Wait longer if it's a CMD_SYNC */
timeout = ktime_add_us(ktime_get(), sync ?
if (wfe) {
wfe();
- } else {
+ } else if (++spin_cnt < ARM_SMMU_CMDQ_SYNC_SPIN_COUNT) {
cpu_relax();
+ continue;
+ } else {
udelay(delay);
delay *= 2;
+ spin_cnt = 0;
}
}