diff mbox

[2/2] iommu/exynos: Workaround FLPD cache flush issues for SYSMMU v5

Message ID 1490001484-18890-2-git-send-email-m.szyprowski@samsung.com (mailing list archive)
State Not Applicable
Headers show

Commit Message

Marek Szyprowski March 20, 2017, 9:17 a.m. UTC
For some unknown reasons, in some cases, FLPD cache invalidation doesn't
work properly with SYSMMU v5 controllers found in Exynos5433 SoCs. This
can be observed by a firmware crash during initialization phase of MFC
video decoder available in the mentioned SoCs when IOMMU support is
enabled. To workaround this issue perform a full TLB/FLPD invalidation
in case of replacing any first level page descriptors in case of SYSMMU v5.

Fixes: 740a01eee9ada ("iommu/exynos: Add support for v5 SYSMMU")
CC: stable@vger.kernel.org # v4.10+
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
The mentioned commit has been merged to v4.6, but this fix applies only for
v4.10+ kernels due to other changes in the surrounding code.
---
 drivers/iommu/exynos-iommu.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Comments

Andrzej Hajda March 20, 2017, 10:31 a.m. UTC | #1
On 20.03.2017 10:17, Marek Szyprowski wrote:
> For some unknown reasons, in some cases, FLPD cache invalidation doesn't
> work properly with SYSMMU v5 controllers found in Exynos5433 SoCs. This
> can be observed by a firmware crash during initialization phase of MFC
> video decoder available in the mentioned SoCs when IOMMU support is
> enabled. To workaround this issue perform a full TLB/FLPD invalidation
> in case of replacing any first level page descriptors in case of SYSMMU v5.

It fixes also crashes of MFC encoder on Exynos5433.

For both patches:
Tested-by: Andrzej Hajda <a.hajda@samsung.com>

Regards
Andrzej

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diff mbox

Patch

diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 32d43f1994e4..c01bfcdb2383 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -513,7 +513,10 @@  static void sysmmu_tlb_invalidate_flpdcache(struct sysmmu_drvdata *data,
 	if (data->active && data->version >= MAKE_MMU_VER(3, 3)) {
 		clk_enable(data->clk_master);
 		if (sysmmu_block(data)) {
-			__sysmmu_tlb_invalidate_entry(data, iova, 1);
+			if (data->version >= MAKE_MMU_VER(5, 0))
+				__sysmmu_tlb_invalidate(data);
+			else
+				__sysmmu_tlb_invalidate_entry(data, iova, 1);
 			sysmmu_unblock(data);
 		}
 		clk_disable(data->clk_master);