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: sta...@vger.kernel.org # v4.10+
Signed-off-by: Marek Szyprowski <m.szyprow...@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(-)

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);
-- 
1.9.1

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