From: Geetha sowjanya <gakula@caviumnetworks.com>
To: robin.murphy@arm.com, will.deacon@arm.com,
        iommu@lists.linux-foundation.org
Cc: catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org, Sunil.Goutham@cavium.com,
        Geetha <gakula@cavium.com>
Subject: [PATCH] iommu/arm-smmu-v3: Increase SMMU CMD queue poll timeout
Date: Mon, 24 Apr 2017 17:29:36 +0530
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From: Geetha <gakula@cavium.com>

When large memory is being unmapped, huge no of tlb invalidation cmds are
submitted followed by a SYNC command. This sometimes hits CMD queue full and
poll on queue drain is being timedout throwing error message 'CMD_SYNC timeout'.

Although there is no functional issue, error message confuses user. Hence increased
poll timeout to 500us

Signed-off-by: Geetha <gakula@cavium.com>
---
 drivers/iommu/arm-smmu-v3.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 591bb96..1dcd154 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -407,7 +407,7 @@
 #define PRIQ_1_ADDR_MASK		0xfffffffffffffUL
 
 /* High-level queue structures */
-#define ARM_SMMU_POLL_TIMEOUT_US	100
+#define ARM_SMMU_POLL_TIMEOUT_US	500
 
 #define MSI_IOVA_BASE			0x8000000
 #define MSI_IOVA_LENGTH			0x100000
-- 
1.9.1