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Commit e3c97196 authored by Russell King's avatar Russell King Committed by Thierry Reding
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iommu/tegra-smmu: Convert to use DMA API



Use the DMA API instead of calling architecture internal functions in
the Tegra SMMU driver.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent d62c7a88
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+85 −54
Original line number Diff line number Diff line
@@ -16,8 +16,6 @@
#include <linux/platform_device.h>
#include <linux/slab.h>

#include <asm/cacheflush.h>

#include <soc/tegra/ahb.h>
#include <soc/tegra/mc.h>

@@ -45,6 +43,7 @@ struct tegra_smmu_as {
	u32 *count;
	struct page **pts;
	struct page *pd;
	dma_addr_t pd_dma;
	unsigned id;
	u32 attr;
};
@@ -82,9 +81,9 @@ 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)
@@ -147,22 +146,15 @@ 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)
{
#ifdef CONFIG_ARM
	phys_addr_t phys = page_to_phys(page) + offset;
#endif
	void *virt = page_address(page) + offset;

#ifdef CONFIG_ARM
	__cpuc_flush_dcache_area(virt, size);
	outer_flush_range(phys, phys + size);
#endif
	addr >>= 12;
	return (addr & smmu->pfn_mask) == addr;
}

#ifdef CONFIG_ARM64
	__flush_dcache_area(virt, 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)
@@ -170,7 +162,7 @@ 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;
@@ -178,15 +170,15 @@ 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);
}

@@ -407,16 +399,26 @@ 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);

@@ -424,6 +426,10 @@ 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,
@@ -433,6 +439,9 @@ 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;
}

@@ -504,63 +513,81 @@ 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 = tegra_smmu_pte_offset(as->pts[pde], iova);

	/* Keep track of entries in this page table. */
	if (pt[iova_pt_index(iova)] == 0)
	if (*pt == 0)
		as->count[pde]++;

	return tegra_smmu_pte_offset(page, iova);
	return pt;
}

static void tegra_smmu_pte_put_use(struct tegra_smmu_as *as, unsigned long iova)
@@ -576,17 +603,20 @@ 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;
@@ -594,15 +624,16 @@ 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);
}
@@ -611,14 +642,14 @@ 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;
@@ -628,14 +659,14 @@ 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;
@@ -645,11 +676,11 @@ 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;