mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-17 01:04:19 +08:00
132 lines
3.1 KiB
C
132 lines
3.1 KiB
C
/*
|
|
* 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>
|
|
|
|
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;
|
|
}
|
|
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);
|
|
|
|
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);
|