forked from rrcarlosr/Jetpack
80 lines
2.0 KiB
C
80 lines
2.0 KiB
C
/*
|
|
* Dynamic DMA mapping support.
|
|
*
|
|
* On cris there is no hardware dynamic DMA address translation,
|
|
* so consistent alloc/free are merely page allocation/freeing.
|
|
* The rest of the dynamic DMA mapping interface is implemented
|
|
* in asm/pci.h.
|
|
*
|
|
* Borrowed from i386.
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/string.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/gfp.h>
|
|
#include <asm/io.h>
|
|
|
|
static void *v32_dma_alloc(struct device *dev, size_t size,
|
|
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
|
|
{
|
|
void *ret;
|
|
|
|
/* ignore region specifiers */
|
|
gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
|
|
|
|
if (dev == NULL || (dev->coherent_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;
|
|
}
|
|
|
|
static void v32_dma_free(struct device *dev, size_t size, void *vaddr,
|
|
dma_addr_t dma_handle, unsigned long attrs)
|
|
{
|
|
free_pages((unsigned long)vaddr, get_order(size));
|
|
}
|
|
|
|
static inline dma_addr_t v32_dma_map_page(struct device *dev,
|
|
struct page *page, unsigned long offset, size_t size,
|
|
enum dma_data_direction direction, unsigned long attrs)
|
|
{
|
|
return page_to_phys(page) + offset;
|
|
}
|
|
|
|
static inline int v32_dma_map_sg(struct device *dev, struct scatterlist *sg,
|
|
int nents, enum dma_data_direction direction,
|
|
unsigned long attrs)
|
|
{
|
|
printk("Map sg\n");
|
|
return nents;
|
|
}
|
|
|
|
static inline int v32_dma_supported(struct device *dev, u64 mask)
|
|
{
|
|
/*
|
|
* we fall back to GFP_DMA when the mask isn't all 1s,
|
|
* so we can't guarantee allocations that must be
|
|
* within a tighter range than GFP_DMA..
|
|
*/
|
|
if (mask < 0x00ffffff)
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
struct dma_map_ops v32_dma_ops = {
|
|
.alloc = v32_dma_alloc,
|
|
.free = v32_dma_free,
|
|
.map_page = v32_dma_map_page,
|
|
.map_sg = v32_dma_map_sg,
|
|
.dma_supported = v32_dma_supported,
|
|
};
|
|
EXPORT_SYMBOL(v32_dma_ops);
|