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132 lines
3.1 KiB
C
132 lines
3.1 KiB
C
/*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file COPYING in the main directory of this archive
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* for more details.
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*/
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#undef DEBUG
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#include <linux/dma-mapping.h>
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#include <linux/device.h>
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#include <linux/kernel.h>
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#include <linux/scatterlist.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <linux/export.h>
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#include <asm/pgalloc.h>
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void *dma_alloc_coherent(struct device *dev, size_t size,
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dma_addr_t *handle, gfp_t flag)
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{
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struct page *page, **map;
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pgprot_t pgprot;
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void *addr;
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int i, order;
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pr_debug("dma_alloc_coherent: %d,%x\n", size, flag);
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size = PAGE_ALIGN(size);
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order = get_order(size);
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page = alloc_pages(flag, order);
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if (!page)
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return NULL;
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*handle = page_to_phys(page);
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map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA);
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if (!map) {
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__free_pages(page, order);
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return NULL;
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}
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split_page(page, order);
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order = 1 << order;
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size >>= PAGE_SHIFT;
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map[0] = page;
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for (i = 1; i < size; i++)
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map[i] = page + i;
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for (; i < order; i++)
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__free_page(page + i);
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pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
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if (CPU_IS_040_OR_060)
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pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
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else
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pgprot_val(pgprot) |= _PAGE_NOCACHE030;
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addr = vmap(map, size, VM_MAP, pgprot);
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kfree(map);
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return addr;
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}
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EXPORT_SYMBOL(dma_alloc_coherent);
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void dma_free_coherent(struct device *dev, size_t size,
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void *addr, dma_addr_t handle)
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{
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pr_debug("dma_free_coherent: %p, %x\n", addr, handle);
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vfree(addr);
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}
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EXPORT_SYMBOL(dma_free_coherent);
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void dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
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size_t size, enum dma_data_direction dir)
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{
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switch (dir) {
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case DMA_TO_DEVICE:
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cache_push(handle, size);
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break;
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case DMA_FROM_DEVICE:
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cache_clear(handle, size);
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break;
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default:
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if (printk_ratelimit())
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printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
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break;
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}
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}
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EXPORT_SYMBOL(dma_sync_single_for_device);
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void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
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enum dma_data_direction dir)
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{
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int i;
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for (i = 0; i < nents; sg++, i++)
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dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
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}
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EXPORT_SYMBOL(dma_sync_sg_for_device);
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dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
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enum dma_data_direction dir)
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{
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dma_addr_t handle = virt_to_bus(addr);
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dma_sync_single_for_device(dev, handle, size, dir);
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return handle;
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}
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EXPORT_SYMBOL(dma_map_single);
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dma_addr_t dma_map_page(struct device *dev, struct page *page,
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unsigned long offset, size_t size,
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enum dma_data_direction dir)
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{
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dma_addr_t handle = page_to_phys(page) + offset;
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dma_sync_single_for_device(dev, handle, size, dir);
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return handle;
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}
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EXPORT_SYMBOL(dma_map_page);
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int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
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enum dma_data_direction dir)
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{
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int i;
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for (i = 0; i < nents; sg++, i++) {
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sg->dma_address = sg_phys(sg);
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dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
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}
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return nents;
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}
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EXPORT_SYMBOL(dma_map_sg);
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