linux_dsm_epyc7002/arch/m68knommu/kernel/dma.c
Greg Ungerer ec40f95db7 m68knommu: fix DMA support for ColdFire
ColdFire CPU family members support DMA (all those with the FEC ethernet
core use it, the rest have dedicated DMA engines). The code support is
just missing a handful of routines for it to be usable by drivers.
Add the missing dma_ functions.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2009-04-22 14:45:08 +10:00

74 lines
1.7 KiB
C

/*
* Dynamic DMA mapping support.
*
* We never have any address translations to worry about, so this
* is just alloc/free.
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/device.h>
#include <linux/dma-mapping.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);
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));
}
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:
flush_dcache_range(handle, size);
break;
case DMA_FROM_DEVICE:
/* Should be clear already */
break;
default:
if (printk_ratelimit())
printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
break;
}
}
EXPORT_SYMBOL(dma_sync_single_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_phys(addr);
flush_dcache_range(handle, size);
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);