- 根目录:
- arch
- nios2
- mm
- dma-mapping.c
/*
* Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
* Copyright (C) 2009 Wind River Systems Inc
* Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
*
* Based on DMA code from MIPS.
*
* 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.
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/scatterlist.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/cache.h>
#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);
/* optimized page clearing */
gfp |= __GFP_ZERO;
if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
gfp |= GFP_DMA;
ret = (void *) __get_free_pages(gfp, get_order(size));
if (ret != NULL) {
*dma_handle = virt_to_phys(ret);
flush_dcache_range((unsigned long) ret,
(unsigned long) ret + size);
ret = UNCAC_ADDR(ret);
}
return ret;
}
EXPORT_SYMBOL(dma_alloc_coherent);
void dma_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle)
{
unsigned long addr = (unsigned long) CAC_ADDR((unsigned long) vaddr);
free_pages(addr, get_order(size));
}
EXPORT_SYMBOL(dma_free_coherent);
int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction direction)
{
int i;
BUG_ON(!valid_dma_direction(direction));
for_each_sg(sg, sg, nents, i) {
void *addr;
addr = sg_virt(sg);
if (addr) {
__dma_sync_for_device(addr, sg->length, direction);
sg->dma_address = sg_phys(sg);
}
}
return nents;
}
EXPORT_SYMBOL(dma_map_sg);
dma_addr_t dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction direction)
{
void *addr;
BUG_ON(!valid_dma_direction(direction));
addr = page_address(page) + offset;
__dma_sync_for_device(addr, size, direction);
return page_to_phys(page) + offset;
}
EXPORT_SYMBOL(dma_map_page);
void dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
enum dma_data_direction direction)
{
BUG_ON(!valid_dma_direction(direction));
__dma_sync_for_cpu(phys_to_virt(dma_address), size, direction);
}
EXPORT_SYMBOL(dma_unmap_page);
void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
enum dma_data_direction direction)
{
void *addr;
int i;
BUG_ON(!valid_dma_direction(direction));
if (direction == DMA_TO_DEVICE)
return;
for_each_sg(sg, sg, nhwentries, i) {
addr = sg_virt(sg);
if (addr)
__dma_sync_for_cpu(addr, sg->length, direction);
}
}
EXPORT_SYMBOL(dma_unmap_sg);
void dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction direction)
{
BUG_ON(!valid_dma_direction(direction));
__dma_sync_for_cpu(phys_to_virt(dma_handle), size, direction);
}
EXPORT_SYMBOL(dma_sync_single_for_cpu);
void dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction direction)
{
BUG_ON(!valid_dma_direction(direction));
__dma_sync_for_device(phys_to_virt(dma_handle), size, direction);
}
EXPORT_SYMBOL(dma_sync_single_for_device);
void dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle,
unsigned long offset, size_t size,
enum dma_data_direction direction)
{
BUG_ON(!valid_dma_direction(direction));
__dma_sync_for_cpu(phys_to_virt(dma_handle), size, direction);
}
EXPORT_SYMBOL(dma_sync_single_range_for_cpu);
void dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
unsigned long offset, size_t size,
enum dma_data_direction direction)
{
BUG_ON(!valid_dma_direction(direction));
__dma_sync_for_device(phys_to_virt(dma_handle), size, direction);
}
EXPORT_SYMBOL(dma_sync_single_range_for_device);
void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
enum dma_data_direction direction)
{
int i;
BUG_ON(!valid_dma_direction(direction));
/* Make sure that gcc doesn't leave the empty loop body. */
for_each_sg(sg, sg, nelems, i)
__dma_sync_for_cpu(sg_virt(sg), sg->length, direction);
}
EXPORT_SYMBOL(dma_sync_sg_for_cpu);
void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
int nelems, enum dma_data_direction direction)
{
int i;
BUG_ON(!valid_dma_direction(direction));
/* Make sure that gcc doesn't leave the empty loop body. */
for_each_sg(sg, sg, nelems, i)
__dma_sync_for_device(sg_virt(sg), sg->length, direction);
}
EXPORT_SYMBOL(dma_sync_sg_for_device);