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-rw-r--r--drivers/iommu/arm-smmu.c18
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 83f50142e63e..618e133f643a 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -162,6 +162,7 @@
#define ARM_SMMU_GR0_sTLBGSTATUS 0x74
#define sTLBGSTATUS_GSACTIVE (1 << 0)
#define TLB_LOOP_TIMEOUT 1000000 /* 1s! */
+#define TLB_SPIN_COUNT 10
/* Stream mapping registers */
#define ARM_SMMU_GR0_SMR(n) (0x800 + ((n) << 2))
@@ -574,18 +575,19 @@ static void __arm_smmu_free_bitmap(unsigned long *map, int idx)
static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu,
void __iomem *sync, void __iomem *status)
{
- int count = 0;
+ unsigned int spin_cnt, delay;
writel_relaxed(0, sync);
- while (readl_relaxed(status) & sTLBGSTATUS_GSACTIVE) {
- cpu_relax();
- if (++count == TLB_LOOP_TIMEOUT) {
- dev_err_ratelimited(smmu->dev,
- "TLB sync timed out -- SMMU may be deadlocked\n");
- return;
+ for (delay = 1; delay < TLB_LOOP_TIMEOUT; delay *= 2) {
+ for (spin_cnt = TLB_SPIN_COUNT; spin_cnt > 0; spin_cnt--) {
+ if (!(readl_relaxed(status) & sTLBGSTATUS_GSACTIVE))
+ return;
+ cpu_relax();
}
- udelay(1);
+ udelay(delay);
}
+ dev_err_ratelimited(smmu->dev,
+ "TLB sync timed out -- SMMU may be deadlocked\n");
}
static void arm_smmu_tlb_sync_global(struct arm_smmu_device *smmu)