#include <linux/genalloc.h>
#include <linux/dma-mapping.h>
#include <linux/dma-contiguous.h>
+#include <linux/mm.h>
+#include <linux/iommu.h>
#include <linux/vmalloc.h>
#include <linux/swiotlb.h>
#include <asm/cacheflush.h>
+#include <asm/dma-iommu.h>
+
+#include "mm.h"
static pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot,
bool coherent)
dev->archdata.dma_coherent = coherent;
__iommu_setup_dma_ops(dev, dma_base, size, iommu);
}
+
+#ifdef CONFIG_ARM64_DMA_USE_IOMMU
+
+/*
+ * Make an area consistent for devices.
+ * Note: Drivers should NOT use this function directly, as it will break
+ * platforms with CONFIG_DMABOUNCE.
+ * Use the driver DMA support - see dma-mapping.h (dma_sync_*)
+ */
+static void __dma_page_cpu_to_dev(struct page *page, unsigned long off,
+ size_t size, enum dma_data_direction dir)
+{
+ __dma_map_area(page_address(page) + off, size, dir);
+}
+
+static void __dma_page_dev_to_cpu(struct page *page, unsigned long off,
+ size_t size, enum dma_data_direction dir)
+{
+ __dma_unmap_area(page_address(page) + off, size, dir);
+
+ /*
+ * Mark the D-cache clean for this page to avoid extra flushing.
+ */
+ if (dir != DMA_TO_DEVICE && off == 0 && size >= PAGE_SIZE)
+ set_bit(PG_dcache_clean, &page->flags);
+}
+
+static int arm_dma_set_mask(struct device *dev, u64 dma_mask)
+{
+ if (!dev->dma_mask || !dma_supported(dev, dma_mask))
+ return -EIO;
+
+ *dev->dma_mask = dma_mask;
+
+ return 0;
+}
+
+/* IOMMU */
+
+static void __dma_clear_buffer(struct page *page, size_t size,
+ struct dma_attrs *attrs)
+{
+ /*
+ * Ensure that the allocated pages are zeroed, and that any data
+ * lurking in the kernel direct-mapped region is invalidated.
+ */
+ void *ptr = page_address(page);
+ if (!dma_get_attr(DMA_ATTR_SKIP_ZEROING, attrs))
+ memset(ptr, 0, size);
+ dmac_flush_range(ptr, ptr + size);
+}
+
+static inline dma_addr_t __alloc_iova(struct dma_iommu_mapping *mapping,
+ size_t size)
+{
+ unsigned int order = get_order(size);
+ unsigned int align = 0;
+ unsigned int count, start;
+ unsigned long flags;
+
+ if (order > CONFIG_ARM64_DMA_IOMMU_ALIGNMENT)
+ order = CONFIG_ARM64_DMA_IOMMU_ALIGNMENT;
+
+ count = ((PAGE_ALIGN(size) >> PAGE_SHIFT) +
+ (1 << mapping->order) - 1) >> mapping->order;
+
+ if (order > mapping->order)
+ align = (1 << (order - mapping->order)) - 1;
+
+ spin_lock_irqsave(&mapping->lock, flags);
+ start = bitmap_find_next_zero_area(mapping->bitmap, mapping->bits, 0,
+ count, align);
+ if (start > mapping->bits) {
+ spin_unlock_irqrestore(&mapping->lock, flags);
+ return DMA_ERROR_CODE;
+ }
+
+ bitmap_set(mapping->bitmap, start, count);
+ spin_unlock_irqrestore(&mapping->lock, flags);
+
+ return mapping->base + (start << (mapping->order + PAGE_SHIFT));
+}
+
+static inline void __free_iova(struct dma_iommu_mapping *mapping,
+ dma_addr_t addr, size_t size)
+{
+ unsigned int start = (addr - mapping->base) >>
+ (mapping->order + PAGE_SHIFT);
+ unsigned int count = ((size >> PAGE_SHIFT) +
+ (1 << mapping->order) - 1) >> mapping->order;
+ unsigned long flags;
+
+ spin_lock_irqsave(&mapping->lock, flags);
+ bitmap_clear(mapping->bitmap, start, count);
+ spin_unlock_irqrestore(&mapping->lock, flags);
+}
+
+static struct page **__iommu_alloc_buffer(struct device *dev, size_t size,
+ gfp_t gfp, struct dma_attrs *attrs)
+{
+ struct page **pages;
+ int count = size >> PAGE_SHIFT;
+ int array_size = count * sizeof(struct page *);
+ int i = 0;
+
+ if (array_size <= PAGE_SIZE)
+ pages = kzalloc(array_size, gfp);
+ else
+ pages = vzalloc(array_size);
+ if (!pages)
+ return NULL;
+
+ if (dma_get_attr(DMA_ATTR_FORCE_CONTIGUOUS, attrs)) {
+ unsigned long order = get_order(size);
+ struct page *page;
+
+ page = dma_alloc_from_contiguous(dev, count, order);
+ if (!page)
+ goto error;
+
+ __dma_clear_buffer(page, size, attrs);
+
+ for (i = 0; i < count; i++)
+ pages[i] = page + i;
+
+ return pages;
+ }
+
+ /*
+ * IOMMU can map any pages, so himem can also be used here
+ */
+ gfp |= __GFP_NOWARN | __GFP_HIGHMEM;
+
+ while (count) {
+ int j, order = __fls(count);
+
+ pages[i] = alloc_pages(gfp, order);
+ while (!pages[i] && order)
+ pages[i] = alloc_pages(gfp, --order);
+ if (!pages[i])
+ goto error;
+
+ if (order) {
+ split_page(pages[i], order);
+ j = 1 << order;
+ while (--j)
+ pages[i + j] = pages[i] + j;
+ }
+
+ __dma_clear_buffer(pages[i], PAGE_SIZE << order, attrs);
+ i += 1 << order;
+ count -= 1 << order;
+ }
+
+ return pages;
+error:
+ while (i--)
+ if (pages[i])
+ __free_pages(pages[i], 0);
+ if (array_size <= PAGE_SIZE)
+ kfree(pages);
+ else
+ vfree(pages);
+ return NULL;
+}
+
+static int __iommu_free_buffer(struct device *dev, struct page **pages,
+ size_t size, struct dma_attrs *attrs)
+{
+ int count = size >> PAGE_SHIFT;
+ int array_size = count * sizeof(struct page *);
+ int i;
+
+ if (dma_get_attr(DMA_ATTR_FORCE_CONTIGUOUS, attrs)) {
+ dma_release_from_contiguous(dev, pages[0], count);
+ } else {
+ for (i = 0; i < count; i++)
+ if (pages[i])
+ __free_pages(pages[i], 0);
+ }
+
+ if (array_size <= PAGE_SIZE)
+ kfree(pages);
+ else
+ vfree(pages);
+ return 0;
+}
+
+/*
+ * Create a CPU mapping for a specified pages
+ */
+static void *
+__iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot,
+ const void *caller)
+{
+ return dma_common_pages_remap(pages, size, VM_USERMAP, prot, caller);
+}
+
+/*
+ * Create a mapping in device IO address space for specified pages
+ */
+static dma_addr_t
+__iommu_create_mapping(struct device *dev, struct page **pages, size_t size)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ dma_addr_t dma_addr, iova;
+ int i, ret;
+
+ dma_addr = __alloc_iova(mapping, size);
+ if (dma_addr == DMA_ERROR_CODE)
+ return dma_addr;
+
+ iova = dma_addr;
+ for (i = 0; i < count; ) {
+ unsigned int next_pfn = page_to_pfn(pages[i]) + 1;
+ phys_addr_t phys = page_to_phys(pages[i]);
+ unsigned int len, j;
+
+ for (j = i + 1; j < count; j++, next_pfn++)
+ if (page_to_pfn(pages[j]) != next_pfn)
+ break;
+
+ len = (j - i) << PAGE_SHIFT;
+ ret = iommu_map(mapping->domain, iova, phys, len,
+ IOMMU_READ|IOMMU_WRITE);
+ if (ret < 0)
+ goto fail;
+ iova += len;
+ i = j;
+ }
+ return dma_addr;
+fail:
+ iommu_unmap(mapping->domain, dma_addr, iova-dma_addr);
+ __free_iova(mapping, dma_addr, size);
+ return DMA_ERROR_CODE;
+}
+
+static int __iommu_remove_mapping(struct device *dev, dma_addr_t iova,
+ size_t size)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+
+ /*
+ * add optional in-page offset from iova to size and align
+ * result to page size
+ */
+ size = PAGE_ALIGN((iova & ~PAGE_MASK) + size);
+ iova &= PAGE_MASK;
+
+ iommu_unmap(mapping->domain, iova, size);
+ __free_iova(mapping, iova, size);
+ return 0;
+}
+
+static struct page **__atomic_get_pages(void *addr)
+{
+ struct page *page;
+ phys_addr_t phys;
+
+ phys = gen_pool_virt_to_phys(atomic_pool, (unsigned long)addr);
+ page = phys_to_page(phys);
+
+ return (struct page **)page;
+}
+
+static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
+{
+ struct vm_struct *area;
+
+ if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
+ return __atomic_get_pages(cpu_addr);
+
+ if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+ return cpu_addr;
+
+ area = find_vm_area(cpu_addr);
+ if (area)
+ return area->pages;
+ return NULL;
+}
+
+static void *__iommu_alloc_atomic(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t flags)
+{
+ struct page *page;
+ void *addr;
+
+ addr = __alloc_from_pool(size, &page, flags);
+ if (!addr)
+ return NULL;
+
+ *handle = __iommu_create_mapping(dev, &page, size);
+ if (*handle == DMA_ERROR_CODE)
+ goto err_mapping;
+
+ return addr;
+
+err_mapping:
+ __free_from_pool(addr, size);
+ return NULL;
+}
+
+static void __iommu_free_atomic(struct device *dev, void *cpu_addr,
+ dma_addr_t handle, size_t size)
+{
+ __iommu_remove_mapping(dev, handle, size);
+ __free_from_pool(cpu_addr, size);
+}
+
+static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
+ dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
+{
+ pgprot_t prot = __get_dma_pgprot(attrs, PAGE_KERNEL, true);
+ struct page **pages;
+ void *addr = NULL;
+
+ *handle = DMA_ERROR_CODE;
+ size = PAGE_ALIGN(size);
+
+ if (!(gfp & __GFP_WAIT))
+ return __iommu_alloc_atomic(dev, size, handle, gfp);
+
+ /*
+ * Following is a work-around (a.k.a. hack) to prevent pages
+ * with __GFP_COMP being passed to split_page() which cannot
+ * handle them. The real problem is that this flag probably
+ * should be 0 on ARM as it is not supported on this
+ * platform; see CONFIG_HUGETLBFS.
+ */
+ gfp &= ~(__GFP_COMP);
+
+ pages = __iommu_alloc_buffer(dev, size, gfp, attrs);
+ if (!pages)
+ return NULL;
+
+ *handle = __iommu_create_mapping(dev, pages, size);
+ if (*handle == DMA_ERROR_CODE)
+ goto err_buffer;
+
+ if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+ return pages;
+
+ addr = __iommu_alloc_remap(pages, size, gfp, prot,
+ __builtin_return_address(0));
+ if (!addr)
+ goto err_mapping;
+
+ return addr;
+
+err_mapping:
+ __iommu_remove_mapping(dev, *handle, size);
+err_buffer:
+ __iommu_free_buffer(dev, pages, size, attrs);
+ return NULL;
+}
+
+static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
+ struct dma_attrs *attrs)
+{
+ unsigned long uaddr = vma->vm_start;
+ unsigned long usize = vma->vm_end - vma->vm_start;
+ struct page **pages = __iommu_get_pages(cpu_addr, attrs);
+
+ vma->vm_page_prot = __get_dma_pgprot(attrs, vma->vm_page_prot, true);
+
+ if (!pages)
+ return -ENXIO;
+
+ do {
+ int ret = vm_insert_page(vma, uaddr, *pages++);
+ if (ret) {
+ pr_err("Remapping memory failed: %d\n", ret);
+ return ret;
+ }
+ uaddr += PAGE_SIZE;
+ usize -= PAGE_SIZE;
+ } while (usize > 0);
+
+ return 0;
+}
+
+/*
+ * free a page as defined by the above mapping.
+ * Must not be called with IRQs disabled.
+ */
+void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
+ dma_addr_t handle, struct dma_attrs *attrs)
+{
+ struct page **pages;
+ size = PAGE_ALIGN(size);
+
+ if (__in_atomic_pool(cpu_addr, size)) {
+ __iommu_free_atomic(dev, cpu_addr, handle, size);
+ return;
+ }
+
+ pages = __iommu_get_pages(cpu_addr, attrs);
+ if (!pages) {
+ WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
+ return;
+ }
+
+ if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
+ dma_common_free_remap(cpu_addr, size, VM_USERMAP);
+
+ __iommu_remove_mapping(dev, handle, size);
+ __iommu_free_buffer(dev, pages, size, attrs);
+}
+
+int arm_iommu_get_sgtable(struct device *dev, struct sg_table *sgt,
+ void *cpu_addr, dma_addr_t dma_addr,
+ size_t size, struct dma_attrs *attrs)
+{
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ struct page **pages = __iommu_get_pages(cpu_addr, attrs);
+
+ if (!pages)
+ return -ENXIO;
+
+ return sg_alloc_table_from_pages(sgt, pages, count, 0, size,
+ GFP_KERNEL);
+}
+
+static int __dma_direction_to_prot(enum dma_data_direction dir)
+{
+ int prot;
+
+ switch (dir) {
+ case DMA_BIDIRECTIONAL:
+ prot = IOMMU_READ | IOMMU_WRITE;
+ break;
+ case DMA_TO_DEVICE:
+ prot = IOMMU_READ;
+ break;
+ case DMA_FROM_DEVICE:
+ prot = IOMMU_WRITE;
+ break;
+ default:
+ prot = 0;
+ }
+
+ return prot;
+}
+
+/*
+ * Map a part of the scatter-gather list into contiguous io address space
+ */
+static int __map_sg_chunk(struct device *dev, struct scatterlist *sg,
+ size_t size, dma_addr_t *handle,
+ enum dma_data_direction dir, struct dma_attrs *attrs,
+ bool is_coherent)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t iova, iova_base;
+ int ret = 0;
+ unsigned int count;
+ struct scatterlist *s;
+ int prot;
+
+ size = PAGE_ALIGN(size);
+ *handle = DMA_ERROR_CODE;
+
+ iova_base = iova = __alloc_iova(mapping, size);
+ if (iova == DMA_ERROR_CODE)
+ return -ENOMEM;
+
+ for (count = 0, s = sg; count < (size >> PAGE_SHIFT); s = sg_next(s)) {
+ phys_addr_t phys = page_to_phys(sg_page(s));
+ unsigned int len = PAGE_ALIGN(s->offset + s->length);
+
+ if (!is_coherent &&
+ !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length,
+ dir);
+
+ prot = __dma_direction_to_prot(dir);
+
+ ret = iommu_map(mapping->domain, iova, phys, len, prot);
+ if (ret < 0)
+ goto fail;
+ count += len >> PAGE_SHIFT;
+ iova += len;
+ }
+ *handle = iova_base;
+
+ return 0;
+fail:
+ iommu_unmap(mapping->domain, iova_base, count * PAGE_SIZE);
+ __free_iova(mapping, iova_base, size);
+ return ret;
+}
+
+static int __iommu_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, struct dma_attrs *attrs,
+ bool is_coherent)
+{
+ struct scatterlist *s = sg, *dma = sg, *start = sg;
+ int i, count = 0;
+ unsigned int offset = s->offset;
+ unsigned int size = s->offset + s->length;
+ unsigned int max = dma_get_max_seg_size(dev);
+
+ for (i = 1; i < nents; i++) {
+ s = sg_next(s);
+
+ s->dma_address = DMA_ERROR_CODE;
+ s->dma_length = 0;
+
+ if (s->offset || (size & ~PAGE_MASK)
+ || size + s->length > max) {
+ if (__map_sg_chunk(dev, start, size, &dma->dma_address,
+ dir, attrs, is_coherent) < 0)
+ goto bad_mapping;
+
+ dma->dma_address += offset;
+ dma->dma_length = size - offset;
+
+ size = offset = s->offset;
+ start = s;
+ dma = sg_next(dma);
+ count += 1;
+ }
+ size += s->length;
+ }
+ if (__map_sg_chunk(dev, start, size, &dma->dma_address, dir, attrs,
+ is_coherent) < 0)
+ goto bad_mapping;
+
+ dma->dma_address += offset;
+ dma->dma_length = size - offset;
+
+ return count+1;
+
+bad_mapping:
+ for_each_sg(sg, s, count, i)
+ __iommu_remove_mapping(dev, sg_dma_address(s), sg_dma_len(s));
+ return 0;
+}
+
+/**
+ * arm_coherent_iommu_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of i/o coherent buffers described by scatterlist in streaming
+ * mode for DMA. The scatter gather list elements are merged together (if
+ * possible) and tagged with the appropriate dma address and length. They are
+ * obtained via sg_dma_{address,length}.
+ */
+int arm_coherent_iommu_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ return __iommu_map_sg(dev, sg, nents, dir, attrs, true);
+}
+
+/**
+ * arm_iommu_map_sg - map a set of SG buffers for streaming mode DMA
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map
+ * @dir: DMA transfer direction
+ *
+ * Map a set of buffers described by scatterlist in streaming mode for DMA.
+ * The scatter gather list elements are merged together (if possible) and
+ * tagged with the appropriate dma address and length. They are obtained via
+ * sg_dma_{address,length}.
+ */
+int arm_iommu_map_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ return __iommu_map_sg(dev, sg, nents, dir, attrs, false);
+}
+
+static void __iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs,
+ bool is_coherent)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i) {
+ if (sg_dma_len(s))
+ __iommu_remove_mapping(dev, sg_dma_address(s),
+ sg_dma_len(s));
+ if (!is_coherent &&
+ !dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ __dma_page_dev_to_cpu(sg_page(s), s->offset,
+ s->length, dir);
+ }
+}
+
+/**
+ * arm_coherent_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_coherent_iommu_unmap_sg(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ __iommu_unmap_sg(dev, sg, nents, dir, attrs, true);
+}
+
+/**
+ * arm_iommu_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to unmap (same as was passed to dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ *
+ * Unmap a set of streaming mode DMA translations. Again, CPU access
+ * rules concerning calls here are the same as for dma_unmap_single().
+ */
+void arm_iommu_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+ enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ __iommu_unmap_sg(dev, sg, nents, dir, attrs, false);
+}
+
+/**
+ * arm_iommu_sync_sg_for_cpu
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map (returned from dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ */
+void arm_iommu_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ __dma_page_dev_to_cpu(sg_page(s), s->offset, s->length, dir);
+
+}
+
+/**
+ * arm_iommu_sync_sg_for_device
+ * @dev: valid struct device pointer
+ * @sg: list of buffers
+ * @nents: number of buffers to map (returned from dma_map_sg)
+ * @dir: DMA transfer direction (same as was passed to dma_map_sg)
+ */
+void arm_iommu_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
+ int nents, enum dma_data_direction dir)
+{
+ struct scatterlist *s;
+ int i;
+
+ for_each_sg(sg, s, nents, i)
+ __dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);
+}
+
+
+/**
+ * arm_coherent_iommu_map_page
+ * @dev: valid struct device pointer
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * Coherent IOMMU aware version of arm_dma_map_page()
+ */
+static dma_addr_t arm_coherent_iommu_map_page(struct device *dev,
+ struct page *page, unsigned long offset, size_t size,
+ enum dma_data_direction dir, struct dma_attrs *attrs)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t dma_addr;
+ int ret, prot, len = PAGE_ALIGN(size + offset);
+
+ dma_addr = __alloc_iova(mapping, len);
+ if (dma_addr == DMA_ERROR_CODE)
+ return dma_addr;
+
+ prot = __dma_direction_to_prot(dir);
+
+ ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len,
+ prot);
+ if (ret < 0)
+ goto fail;
+
+ return dma_addr + offset;
+fail:
+ __free_iova(mapping, dma_addr, len);
+ return DMA_ERROR_CODE;
+}
+
+/**
+ * arm_iommu_map_page
+ * @dev: valid struct device pointer
+ * @page: page that buffer resides in
+ * @offset: offset into page for start of buffer
+ * @size: size of buffer to map
+ * @dir: DMA transfer direction
+ *
+ * IOMMU aware version of arm_dma_map_page()
+ */
+static dma_addr_t arm_iommu_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+
+ return arm_coherent_iommu_map_page(dev, page, offset, size, dir, attrs);
+}
+
+/**
+ * arm_coherent_iommu_unmap_page
+ * @dev: valid struct device pointer
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * Coherent IOMMU aware version of arm_dma_unmap_page()
+ */
+static void arm_coherent_iommu_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t iova = handle & PAGE_MASK;
+ int offset = handle & ~PAGE_MASK;
+ int len = PAGE_ALIGN(size + offset);
+
+ if (!iova)
+ return;
+
+ iommu_unmap(mapping->domain, iova, len);
+ __free_iova(mapping, iova, len);
+}
+
+/**
+ * arm_iommu_unmap_page
+ * @dev: valid struct device pointer
+ * @handle: DMA address of buffer
+ * @size: size of buffer (same as passed to dma_map_page)
+ * @dir: DMA transfer direction (same as passed to dma_map_page)
+ *
+ * IOMMU aware version of arm_dma_unmap_page()
+ */
+static void arm_iommu_unmap_page(struct device *dev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(
+ mapping->domain, iova));
+ int offset = handle & ~PAGE_MASK;
+ int len = PAGE_ALIGN(size + offset);
+
+ if (!iova)
+ return;
+
+ if (!dma_get_attr(DMA_ATTR_SKIP_CPU_SYNC, attrs))
+ __dma_page_dev_to_cpu(page, offset, size, dir);
+
+ iommu_unmap(mapping->domain, iova, len);
+ __free_iova(mapping, iova, len);
+}
+
+static void arm_iommu_sync_single_for_cpu(struct device *dev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(
+ mapping->domain, iova));
+ unsigned int offset = handle & ~PAGE_MASK;
+
+ if (!iova)
+ return;
+
+ __dma_page_dev_to_cpu(page, offset, size, dir);
+}
+
+static void arm_iommu_sync_single_for_device(struct device *dev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ struct dma_iommu_mapping *mapping = dev->archdata.mapping;
+ dma_addr_t iova = handle & PAGE_MASK;
+ struct page *page = phys_to_page(iommu_iova_to_phys(
+ mapping->domain, iova));
+ unsigned int offset = handle & ~PAGE_MASK;
+
+ if (!iova)
+ return;
+
+ __dma_page_cpu_to_dev(page, offset, size, dir);
+}
+
+const struct dma_map_ops iommu_ops = {
+ .alloc = arm_iommu_alloc_attrs,
+ .free = arm_iommu_free_attrs,
+ .mmap = arm_iommu_mmap_attrs,
+ .get_sgtable = arm_iommu_get_sgtable,
+
+ .map_page = arm_iommu_map_page,
+ .unmap_page = arm_iommu_unmap_page,
+ .sync_single_for_cpu = arm_iommu_sync_single_for_cpu,
+ .sync_single_for_device = arm_iommu_sync_single_for_device,
+
+ .map_sg = arm_iommu_map_sg,
+ .unmap_sg = arm_iommu_unmap_sg,
+ .sync_sg_for_cpu = arm_iommu_sync_sg_for_cpu,
+ .sync_sg_for_device = arm_iommu_sync_sg_for_device,
+
+ .set_dma_mask = arm_dma_set_mask,
+};
+
+const struct dma_map_ops iommu_coherent_ops = {
+ .alloc = arm_iommu_alloc_attrs,
+ .free = arm_iommu_free_attrs,
+ .mmap = arm_iommu_mmap_attrs,
+ .get_sgtable = arm_iommu_get_sgtable,
+
+ .map_page = arm_coherent_iommu_map_page,
+ .unmap_page = arm_coherent_iommu_unmap_page,
+
+ .map_sg = arm_coherent_iommu_map_sg,
+ .unmap_sg = arm_coherent_iommu_unmap_sg,
+
+ .set_dma_mask = arm_dma_set_mask,
+};
+
+/**
+ * arm_iommu_create_mapping
+ * @bus: pointer to the bus holding the client device (for IOMMU calls)
+ * @base: start address of the valid IO address space
+ * @size: size of the valid IO address space
+ * @order: accuracy of the IO addresses allocations
+ *
+ * Creates a mapping structure which holds information about used/unused
+ * IO address ranges, which is required to perform memory allocation and
+ * mapping with IOMMU aware functions.
+ *
+ * The client device need to be attached to the mapping with
+ * arm_iommu_attach_device function.
+ */
+struct dma_iommu_mapping *
+arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,
+ int order)
+{
+ unsigned int count = size >> (PAGE_SHIFT + order);
+ unsigned int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
+ struct dma_iommu_mapping *mapping;
+ int err = -ENOMEM;
+
+ if (!count)
+ return ERR_PTR(-EINVAL);
+
+ mapping = kzalloc(sizeof(struct dma_iommu_mapping), GFP_KERNEL);
+ if (!mapping)
+ goto err;
+
+ mapping->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
+ if (!mapping->bitmap)
+ goto err2;
+
+ mapping->base = base;
+ mapping->bits = BITS_PER_BYTE * bitmap_size;
+ mapping->order = order;
+ spin_lock_init(&mapping->lock);
+
+ mapping->domain = iommu_domain_alloc(bus);
+ if (!mapping->domain)
+ goto err3;
+
+ kref_init(&mapping->kref);
+ return mapping;
+err3:
+ kfree(mapping->bitmap);
+err2:
+ kfree(mapping);
+err:
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(arm_iommu_create_mapping);
+
+static void release_iommu_mapping(struct kref *kref)
+{
+ struct dma_iommu_mapping *mapping =
+ container_of(kref, struct dma_iommu_mapping, kref);
+
+ iommu_domain_free(mapping->domain);
+ kfree(mapping->bitmap);
+ kfree(mapping);
+}
+
+void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping)
+{
+ if (mapping)
+ kref_put(&mapping->kref, release_iommu_mapping);
+}
+EXPORT_SYMBOL(arm_iommu_release_mapping);
+
+/**
+ * arm_iommu_attach_device
+ * @dev: valid struct device pointer
+ * @mapping: io address space mapping structure (returned from
+ * arm_iommu_create_mapping)
+ *
+ * Attaches specified io address space mapping to the provided device,
+ * this replaces the dma operations (dma_map_ops pointer) with the
+ * IOMMU aware version. More than one client might be attached to
+ * the same io address space mapping.
+ */
+int arm_iommu_attach_device(struct device *dev,
+ struct dma_iommu_mapping *mapping)
+{
+ int err;
+
+ err = iommu_attach_device(mapping->domain, dev);
+ if (err)
+ return err;
+
+ kref_get(&mapping->kref);
+ dev->archdata.mapping = mapping;
+ dev->archdata.dma_ops = &iommu_ops;
+ pr_debug("Attached IOMMU controller to %s device.\n", dev_name(dev));
+ return 0;
+}
+EXPORT_SYMBOL(arm_iommu_attach_device);
+
+/**
+ * arm_iommu_detach_device
+ * @dev: valid struct device pointer
+ *
+ * Detaches the provided device from a previously attached map.
+ * This voids the dma operations (dma_map_ops pointer)
+ */
+void arm_iommu_detach_device(struct device *dev)
+{
+ struct dma_iommu_mapping *mapping;
+
+ mapping = to_dma_iommu_mapping(dev);
+ if (!mapping) {
+ dev_warn(dev, "Not attached\n");
+ return;
+ }
+
+ iommu_detach_device(mapping->domain, dev);
+ kref_put(&mapping->kref, release_iommu_mapping);
+ dev->archdata.mapping = NULL;
+ dev->archdata.dma_ops = NULL;
+
+ pr_debug("Detached IOMMU controller from %s device.\n", dev_name(dev));
+}
+EXPORT_SYMBOL(arm_iommu_detach_device);
+
+#endif
projects / karo-tx-linux.git / commitdiff