[PATCH v1 3/3] iommu/tegra-smmu: Respect IOMMU API read-write protections

[Dmitry Osipenko]

Set PTE read/write attributes accordingly to the the protections requested
by IOMMU API.

Signed-off-by: Dmitry Osipenko <dig...@gmail.com>
---
 drivers/iommu/tegra-smmu.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 27b1249f0773..463ee08f7d3a 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -145,8 +145,6 @@ static inline u32 smmu_readl(struct tegra_smmu *smmu, 
unsigned long offset)
 
 #define SMMU_PDE_ATTR          (SMMU_PDE_READABLE | SMMU_PDE_WRITABLE | \
                                 SMMU_PDE_NONSECURE)
-#define SMMU_PTE_ATTR          (SMMU_PTE_READABLE | SMMU_PTE_WRITABLE | \
-                                SMMU_PTE_NONSECURE)
 
 static unsigned int iova_pd_index(unsigned long iova)
 {
@@ -659,6 +657,7 @@ static int tegra_smmu_map(struct iommu_domain *domain, 
unsigned long iova,
 {
        struct tegra_smmu_as *as = to_smmu_as(domain);
        dma_addr_t pte_dma;
+       u32 pte_attrs;
        u32 *pte;
 
        pte = as_get_pte(as, iova, &pte_dma);
@@ -669,8 +668,16 @@ static int tegra_smmu_map(struct iommu_domain *domain, 
unsigned long iova,
        if (*pte == 0)
                tegra_smmu_pte_get_use(as, iova);
 
+       pte_attrs = SMMU_PTE_NONSECURE;
+
+       if (prot & IOMMU_READ)
+               pte_attrs |= SMMU_PTE_READABLE;
+
+       if (prot & IOMMU_WRITE)
+               pte_attrs |= SMMU_PTE_WRITABLE;
+
        tegra_smmu_set_pte(as, iova, pte, pte_dma,
-                          __phys_to_pfn(paddr) | SMMU_PTE_ATTR);
+                          __phys_to_pfn(paddr) | pte_attrs);
 
        return 0;
 }
-- 
2.20.1