[PATCH 4.9 026/104] iommu/exynos: Workaround FLPD cache flush issues for SYSMMU v5

From: Greg Kroah-Hartman
Date: Fri Dec 22 2017 - 05:17:57 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>


[ Upstream commit cd37a296a9f890586665bb8974a8b17ee2f17d6d ]

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@xxxxxxxxxxxxxxx # v4.10+
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Tested-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iommu/exynos-iommu.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -543,7 +543,10 @@ static void sysmmu_tlb_invalidate_flpdca
if (is_sysmmu_active(data) && 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);