[PATCH] iommu/rockchip: fix permission bits in page table entries v2

Michael Riesch michael.riesch at wolfvision.net
Tue Nov 1 23:35:53 PDT 2022


As pointed out in the corresponding downstream fix [0], the permission bits
of the page table entries are compatible between v1 and v2 of the IOMMU.
This is in contrast to the current mainline code that incorrectly assumes
that the read and write permission bits are switched. Fix the permission
bits by reusing the v1 bit defines.

[0] https://github.com/rockchip-linux/kernel/commit/e3bc123a2260145e34b57454da3db0edd117eb8e

Fixes: c55356c534aa ("iommu: rockchip: Add support for iommu v2")
Signed-off-by: Michael Riesch <michael.riesch at wolfvision.net>
---
 drivers/iommu/rockchip-iommu.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index a3fc59b814ab..a68eadd64f38 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -280,19 +280,17 @@ static u32 rk_mk_pte(phys_addr_t page, int prot)
  *  11:9 - Page address bit 34:32
  *   8:4 - Page address bit 39:35
  *     3 - Security
- *     2 - Readable
- *     1 - Writable
+ *     2 - Writable
+ *     1 - Readable
  *     0 - 1 if Page @ Page address is valid
  */
-#define RK_PTE_PAGE_READABLE_V2      BIT(2)
-#define RK_PTE_PAGE_WRITABLE_V2      BIT(1)
 
 static u32 rk_mk_pte_v2(phys_addr_t page, int prot)
 {
 	u32 flags = 0;
 
-	flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE_V2 : 0;
-	flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE_V2 : 0;
+	flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0;
+	flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0;
 
 	return rk_mk_dte_v2(page) | flags;
 }
-- 
2.30.2




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