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/*
* 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/scatterlist.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
#include <asm/pgalloc.h>
#ifdef CONFIG_MMU
void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t 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, VM_MAP, pgprot);
kfree(map);
return addr;
}
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);
}
#else
#include <asm/cacheflush.h>
void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp)
{
void *ret;
/* ignore region specifiers */
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
if (dev == NULL || (*dev->dma_mask < 0xffffffff))
gfp |= GFP_DMA;
ret = (void *)__get_free_pages(gfp, get_order(size));
if (ret != NULL) {
memset(ret, 0, size);
*dma_handle = virt_to_phys(ret);
}
return ret;
}
void dma_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
free_pages((unsigned long)vaddr, get_order(size));
}
#endif /* CONFIG_MMU */
EXPORT_SYMBOL(dma_alloc_coherent);
EXPORT_SYMBOL(dma_free_coherent);
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 = sg_phys(sg);
dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
}
return nents;
}
EXPORT_SYMBOL(dma_map_sg);
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