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>
This commit is contained in:
Russell King 2015-07-27 13:30:12 +01:00 committed by Thierry Reding
parent 7ffc6f066e
commit 4080e99b83

View file

@ -495,6 +495,27 @@ static void tegra_smmu_detach_dev(struct iommu_domain *domain, struct device *de
}
}
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 *tegra_smmu_pte_lookup(struct tegra_smmu_as *as, unsigned long iova,
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 @@ static u32 *as_get_pte(struct tegra_smmu_as *as, dma_addr_t iova,
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_get_use(struct tegra_smmu_as *as, unsigned long iova)
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 @@ static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
* 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;