iommu/tegra-smmu: Factor out tegra_smmu_set_pde()
This code is used both when creating a new page directory entry and when
tearing it down, with only the PDE value changing between both cases.
Factor the code out so that it can be reused.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[treding@nvidia.com: make commit message more accurate]
Signed-off-by: Thierry Reding <treding@nvidia.com>
diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 74ad1f4..2f1481a 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -495,6 +495,27 @@
}
}
+static void tegra_smmu_set_pde(struct tegra_smmu_as *as, unsigned long iova,
+ u32 value)
+{
+ unsigned int pd_index = iova_pd_index(iova);
+ struct tegra_smmu *smmu = as->smmu;
+ u32 *pd = page_address(as->pd);
+ unsigned long offset = pd_index * sizeof(*pd);
+
+ /* Set the page directory entry first */
+ pd[pd_index] = value;
+
+ /* The flush the page directory entry from caches */
+ dma_sync_single_range_for_device(smmu->dev, as->pd_dma, offset,
+ sizeof(*pd), DMA_TO_DEVICE);
+
+ /* And flush the iommu */
+ smmu_flush_ptc(smmu, as->pd_dma, offset);
+ smmu_flush_tlb_section(smmu, as->id, iova);
+ smmu_flush(smmu);
+}
+
static u32 *tegra_smmu_pte_offset(struct page *pt_page, unsigned long iova)
{
u32 *pt = page_address(pt_page);
@@ -522,7 +543,6 @@
static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
dma_addr_t *dmap)
{
- u32 *pd = page_address(as->pd);
unsigned int pde = iova_pd_index(iova);
struct tegra_smmu *smmu = as->smmu;
@@ -550,16 +570,13 @@
as->pts[pde] = page;
- pd[pde] = SMMU_MK_PDE(dma, SMMU_PDE_ATTR | SMMU_PDE_NEXT);
-
- 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);
+ tegra_smmu_set_pde(as, iova, SMMU_MK_PDE(dma, SMMU_PDE_ATTR |
+ SMMU_PDE_NEXT));
*dmap = dma;
} else {
+ u32 *pd = page_address(as->pd);
+
*dmap = smmu_pde_to_dma(pd[pde]);
}
@@ -575,9 +592,7 @@
static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
{
- struct tegra_smmu *smmu = as->smmu;
unsigned int pde = iova_pd_index(iova);
- u32 *pd = page_address(as->pd);
struct page *page = as->pts[pde];
/*
@@ -585,20 +600,12 @@
* memory page to the system.
*/
if (--as->count[pde] == 0) {
- unsigned int offset = pde * sizeof(*pd);
+ struct tegra_smmu *smmu = as->smmu;
+ u32 *pd = page_address(as->pd);
dma_addr_t pte_dma = smmu_pde_to_dma(pd[pde]);
- /* Clear the page directory entry first */
- pd[pde] = 0;
+ tegra_smmu_set_pde(as, iova, 0);
- /* Flush the page directory entry */
- 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);
__free_page(page);
as->pts[pde] = NULL;