[PATCH 13/18] iommu: tegra-smmu: convert to use DMA API
Russell King
rmk+kernel at arm.linux.org.uk
Mon Jul 27 05:29:52 PDT 2015
Use the DMA API instead of calling architecture internal functions in
the Tegra SMMU driver.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
drivers/iommu/tegra-smmu.c | 129 +++++++++++++++++++++++++++++----------------
1 file changed, 84 insertions(+), 45 deletions(-)
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index c54b0afda475..d4264e2bdd69 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -45,6 +45,7 @@ struct tegra_smmu_as {
u32 *count;
struct page **pts;
struct page *pd;
+ dma_addr_t pd_dma;
unsigned id;
u32 attr;
};
@@ -82,9 +83,9 @@ static inline u32 smmu_readl(struct tegra_smmu *smmu, unsigned long offset)
#define SMMU_PTB_ASID_VALUE(x) ((x) & 0x7f)
#define SMMU_PTB_DATA 0x020
-#define SMMU_PTB_DATA_VALUE(page, attr) (page_to_phys(page) >> 12 | (attr))
+#define SMMU_PTB_DATA_VALUE(dma, attr) ((dma) >> 12 | (attr))
-#define SMMU_MK_PDE(page, attr) (page_to_phys(page) >> SMMU_PTE_SHIFT | (attr))
+#define SMMU_MK_PDE(dma, attr) ((dma) >> SMMU_PTE_SHIFT | (attr))
#define SMMU_TLB_FLUSH 0x030
#define SMMU_TLB_FLUSH_VA_MATCH_ALL (0 << 0)
@@ -147,16 +148,15 @@ static unsigned int iova_pt_index(unsigned long iova)
return (iova >> SMMU_PTE_SHIFT) & (SMMU_NUM_PTE - 1);
}
-static void smmu_flush_dcache(struct page *page, unsigned long offset,
- size_t size)
+static bool smmu_dma_addr_valid(struct tegra_smmu *smmu, dma_addr_t addr)
{
- phys_addr_t phys = page_to_phys(page) + offset;
- void *virt = page_address(page) + offset;
+ addr >>= 12;
+ return (addr & smmu->pfn_mask) == addr;
+}
- __cpuc_flush_dcache_area(virt, size);
-#ifdef CONFIG_ARM
- outer_flush_range(phys, phys + size);
-#endif
+static dma_addr_t smmu_pde_to_dma(u32 pde)
+{
+ return pde << 12;
}
static void smmu_flush_ptc_all(struct tegra_smmu *smmu)
@@ -164,7 +164,7 @@ static void smmu_flush_ptc_all(struct tegra_smmu *smmu)
smmu_writel(smmu, SMMU_PTC_FLUSH_TYPE_ALL, SMMU_PTC_FLUSH);
}
-static inline void smmu_flush_ptc(struct tegra_smmu *smmu, phys_addr_t phys,
+static inline void smmu_flush_ptc(struct tegra_smmu *smmu, dma_addr_t dma,
unsigned long offset)
{
u32 value;
@@ -172,15 +172,15 @@ static inline void smmu_flush_ptc(struct tegra_smmu *smmu, phys_addr_t phys,
offset &= ~(smmu->mc->soc->atom_size - 1);
if (smmu->mc->soc->num_address_bits > 32) {
-#ifdef CONFIG_PHYS_ADDR_T_64BIT
- value = (phys >> 32) & SMMU_PTC_FLUSH_HI_MASK;
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+ value = (dma >> 32) & SMMU_PTC_FLUSH_HI_MASK;
#else
value = 0;
#endif
smmu_writel(smmu, value, SMMU_PTC_FLUSH_HI);
}
- value = (phys + offset) | SMMU_PTC_FLUSH_TYPE_ADR;
+ value = (dma + offset) | SMMU_PTC_FLUSH_TYPE_ADR;
smmu_writel(smmu, value, SMMU_PTC_FLUSH);
}
@@ -401,16 +401,26 @@ static int tegra_smmu_as_prepare(struct tegra_smmu *smmu,
return 0;
}
+ as->pd_dma = dma_map_page(smmu->dev, as->pd, 0, SMMU_SIZE_PD,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(smmu->dev, as->pd_dma))
+ return -ENOMEM;
+
+ /* We can't handle 64-bit DMA addresses */
+ if (!smmu_dma_addr_valid(smmu, as->pd_dma)) {
+ err = -ENOMEM;
+ goto err_unmap;
+ }
+
err = tegra_smmu_alloc_asid(smmu, &as->id);
if (err < 0)
- return err;
+ goto err_unmap;
- smmu_flush_dcache(as->pd, 0, SMMU_SIZE_PD);
- smmu_flush_ptc(smmu, page_to_phys(as->pd), 0);
+ smmu_flush_ptc(smmu, as->pd_dma, 0);
smmu_flush_tlb_asid(smmu, as->id);
smmu_writel(smmu, as->id & 0x7f, SMMU_PTB_ASID);
- value = SMMU_PTB_DATA_VALUE(as->pd, as->attr);
+ value = SMMU_PTB_DATA_VALUE(as->pd_dma, as->attr);
smmu_writel(smmu, value, SMMU_PTB_DATA);
smmu_flush(smmu);
@@ -418,6 +428,10 @@ static int tegra_smmu_as_prepare(struct tegra_smmu *smmu,
as->use_count++;
return 0;
+
+err_unmap:
+ dma_unmap_page(smmu->dev, as->pd_dma, SMMU_SIZE_PD, DMA_TO_DEVICE);
+ return err;
}
static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
@@ -427,6 +441,9 @@ static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
return;
tegra_smmu_free_asid(smmu, as->id);
+
+ dma_unmap_page(smmu->dev, as->pd_dma, SMMU_SIZE_PD, DMA_TO_DEVICE);
+
as->smmu = NULL;
}
@@ -498,63 +515,81 @@ static u32 *tegra_smmu_pte_offset(struct page *pt_page, unsigned long iova)
}
static u32 *tegra_smmu_pte_lookup(struct tegra_smmu_as *as, unsigned long iova,
- struct page **pagep)
+ dma_addr_t *dmap)
{
unsigned int pd_index = iova_pd_index(iova);
struct page *pt_page;
+ u32 *pd;
pt_page = as->pts[pd_index];
if (!pt_page)
return NULL;
- *pagep = pt_page;
+ pd = page_address(as->pd);
+ *dmap = smmu_pde_to_dma(pd[pd_index]);
return tegra_smmu_pte_offset(pt_page, iova);
}
static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
- struct page **pagep)
+ dma_addr_t *dmap)
{
u32 *pd = page_address(as->pd), *pt;
unsigned int pde = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
- struct page *page;
unsigned int i;
if (!as->pts[pde]) {
+ struct page *page;
+ dma_addr_t dma;
+
page = alloc_page(GFP_KERNEL | __GFP_DMA);
if (!page)
return NULL;
pt = page_address(page);
- SetPageReserved(page);
for (i = 0; i < SMMU_NUM_PTE; i++)
pt[i] = 0;
+ dma = dma_map_page(smmu->dev, page, 0, SMMU_SIZE_PT,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(smmu->dev, dma)) {
+ __free_page(page);
+ return NULL;
+ }
+
+ if (!smmu_dma_addr_valid(smmu, dma)) {
+ dma_unmap_page(smmu->dev, dma, SMMU_SIZE_PT,
+ DMA_TO_DEVICE);
+ __free_page(page);
+ return NULL;
+ }
+
as->pts[pde] = page;
- smmu_flush_dcache(page, 0, SMMU_SIZE_PT);
+ SetPageReserved(page);
- pd[pde] = SMMU_MK_PDE(page, SMMU_PDE_ATTR | SMMU_PDE_NEXT);
+ pd[pde] = SMMU_MK_PDE(dma, SMMU_PDE_ATTR | SMMU_PDE_NEXT);
- smmu_flush_dcache(as->pd, pde << 2, 4);
- smmu_flush_ptc(smmu, page_to_phys(as->pd), pde << 2);
+ dma_sync_single_range_for_device(smmu->dev, as->pd_dma,
+ pde << 2, 4, DMA_TO_DEVICE);
+ smmu_flush_ptc(smmu, as->pd_dma, pde << 2);
smmu_flush_tlb_section(smmu, as->id, iova);
smmu_flush(smmu);
+
+ *dmap = dma;
} else {
- page = as->pts[pde];
+ *dmap = smmu_pde_to_dma(pd[pde]);
}
- *pagep = page;
-
- pt = page_address(page);
+ pt = page_address(as->pts[pde]);
/* Keep track of entries in this page table. */
if (pt[iova_pt_index(iova)] == 0)
as->count[pde]++;
- return tegra_smmu_pte_offset(page, iova);
+ return tegra_smmu_pte_offset(as->pts[pde], iova);
}
static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
@@ -570,17 +605,20 @@ static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
*/
if (--as->count[pde] == 0) {
unsigned int offset = pde * sizeof(*pd);
+ dma_addr_t pte_dma = smmu_pde_to_dma(pd[pde]);
/* Clear the page directory entry first */
pd[pde] = 0;
/* Flush the page directory entry */
- smmu_flush_dcache(as->pd, offset, sizeof(*pd));
- smmu_flush_ptc(smmu, page_to_phys(as->pd), offset);
+ dma_sync_single_range_for_device(smmu->dev, as->pd_dma, offset,
+ sizeof(*pd), DMA_TO_DEVICE);
+ smmu_flush_ptc(smmu, as->pd_dma, offset);
smmu_flush_tlb_section(smmu, as->id, iova);
smmu_flush(smmu);
/* Finally, free the page */
+ dma_unmap_page(smmu->dev, pte_dma, SMMU_SIZE_PT, DMA_TO_DEVICE);
ClearPageReserved(page);
__free_page(page);
as->pts[pde] = NULL;
@@ -588,15 +626,16 @@ static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
}
static void tegra_smmu_set_pte(struct tegra_smmu_as *as, unsigned long iova,
- u32 *pte, struct page *pte_page, u32 val)
+ u32 *pte, dma_addr_t pte_dma, u32 val)
{
struct tegra_smmu *smmu = as->smmu;
unsigned long offset = offset_in_page(pte);
*pte = val;
- smmu_flush_dcache(pte_page, offset, 4);
- smmu_flush_ptc(smmu, page_to_phys(pte_page), offset);
+ dma_sync_single_range_for_device(smmu->dev, pte_dma, offset,
+ 4, DMA_TO_DEVICE);
+ smmu_flush_ptc(smmu, pte_dma, offset);
smmu_flush_tlb_group(smmu, as->id, iova);
smmu_flush(smmu);
}
@@ -605,14 +644,14 @@ static int tegra_smmu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, int prot)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
- struct page *page;
+ dma_addr_t pte_dma;
u32 *pte;
- pte = as_get_pte(as, iova, &page);
+ pte = as_get_pte(as, iova, &pte_dma);
if (!pte)
return -ENOMEM;
- tegra_smmu_set_pte(as, iova, pte, page,
+ tegra_smmu_set_pte(as, iova, pte, pte_dma,
__phys_to_pfn(paddr) | SMMU_PTE_ATTR);
return 0;
@@ -622,14 +661,14 @@ static size_t tegra_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
- struct page *pte_page;
+ dma_addr_t pte_dma;
u32 *pte;
- pte = tegra_smmu_pte_lookup(as, iova, &pte_page);
+ pte = tegra_smmu_pte_lookup(as, iova, &pte_dma);
if (!pte || !*pte)
return 0;
- tegra_smmu_set_pte(as, iova, pte, pte_page, 0);
+ tegra_smmu_set_pte(as, iova, pte, pte_dma, 0);
tegra_smmu_pte_put_use(as, iova);
return size;
@@ -639,11 +678,11 @@ static phys_addr_t tegra_smmu_iova_to_phys(struct iommu_domain *domain,
dma_addr_t iova)
{
struct tegra_smmu_as *as = to_smmu_as(domain);
- struct page *pte_page;
unsigned long pfn;
+ dma_addr_t pte_dma;
u32 *pte;
- pte = tegra_smmu_pte_lookup(as, iova, &pte_page);
+ pte = tegra_smmu_pte_lookup(as, iova, &pte_dma);
if (!pte || !*pte)
return 0;
--
2.1.0
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