diff options
Diffstat (limited to 'arch/m68k/kernel/dma.c')
-rw-r--r-- | arch/m68k/kernel/dma.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c new file mode 100644 index 0000000..fc449f8 --- /dev/null +++ b/arch/m68k/kernel/dma.c @@ -0,0 +1,129 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +#undef DEBUG + +#include <linux/dma-mapping.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/vmalloc.h> + +#include <asm/pgalloc.h> +#include <asm/scatterlist.h> + +void *dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *handle, int flag) +{ + struct page *page, **map; + pgprot_t pgprot; + void *addr; + int i, order; + + pr_debug("dma_alloc_coherent: %d,%x\n", size, flag); + + size = PAGE_ALIGN(size); + order = get_order(size); + + page = alloc_pages(flag, order); + if (!page) + return NULL; + + *handle = page_to_phys(page); + map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA); + if (!map) { + __free_pages(page, order); + return NULL; + } + split_page(page, order); + + order = 1 << order; + size >>= PAGE_SHIFT; + map[0] = page; + for (i = 1; i < size; i++) + map[i] = page + i; + for (; i < order; i++) + __free_page(page + i); + pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY); + if (CPU_IS_040_OR_060) + pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S; + else + pgprot_val(pgprot) |= _PAGE_NOCACHE030; + addr = vmap(map, size, flag, pgprot); + kfree(map); + + return addr; +} +EXPORT_SYMBOL(dma_alloc_coherent); + +void dma_free_coherent(struct device *dev, size_t size, + void *addr, dma_addr_t handle) +{ + pr_debug("dma_free_coherent: %p, %x\n", addr, handle); + vfree(addr); +} +EXPORT_SYMBOL(dma_free_coherent); + +inline void dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size, + enum dma_data_direction dir) +{ + switch (dir) { + case DMA_TO_DEVICE: + cache_push(handle, size); + break; + case DMA_FROM_DEVICE: + cache_clear(handle, size); + break; + default: + if (printk_ratelimit()) + printk("dma_sync_single_for_device: unsupported dir %u\n", dir); + break; + } +} +EXPORT_SYMBOL(dma_sync_single_for_device); + +void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + int i; + + for (i = 0; i < nents; sg++, i++) + dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir); +} +EXPORT_SYMBOL(dma_sync_sg_for_device); + +dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size, + enum dma_data_direction dir) +{ + dma_addr_t handle = virt_to_bus(addr); + + dma_sync_single_for_device(dev, handle, size, dir); + return handle; +} +EXPORT_SYMBOL(dma_map_single); + +dma_addr_t dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir) +{ + dma_addr_t handle = page_to_phys(page) + offset; + + dma_sync_single_for_device(dev, handle, size, dir); + return handle; +} +EXPORT_SYMBOL(dma_map_page); + +int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir) +{ + int i; + + for (i = 0; i < nents; sg++, i++) { + sg->dma_address = page_to_phys(sg->page) + sg->offset; + dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir); + } + return nents; +} +EXPORT_SYMBOL(dma_map_sg); |