mirror of https://gitee.com/openkylin/linux.git
215 lines
5.4 KiB
C
215 lines
5.4 KiB
C
/*
|
|
* Copyright (C) 2009-2010 PetaLogix
|
|
* Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation
|
|
*
|
|
* Provide default implementations of the DMA mapping callbacks for
|
|
* directly mapped busses.
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/dma-mapping.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/dma-debug.h>
|
|
#include <linux/export.h>
|
|
#include <linux/bug.h>
|
|
|
|
#define NOT_COHERENT_CACHE
|
|
|
|
static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
|
|
dma_addr_t *dma_handle, gfp_t flag,
|
|
unsigned long attrs)
|
|
{
|
|
#ifdef NOT_COHERENT_CACHE
|
|
return consistent_alloc(flag, size, dma_handle);
|
|
#else
|
|
void *ret;
|
|
struct page *page;
|
|
int node = dev_to_node(dev);
|
|
|
|
/* ignore region specifiers */
|
|
flag &= ~(__GFP_HIGHMEM);
|
|
|
|
page = alloc_pages_node(node, flag, get_order(size));
|
|
if (page == NULL)
|
|
return NULL;
|
|
ret = page_address(page);
|
|
memset(ret, 0, size);
|
|
*dma_handle = virt_to_phys(ret);
|
|
|
|
return ret;
|
|
#endif
|
|
}
|
|
|
|
static void dma_direct_free_coherent(struct device *dev, size_t size,
|
|
void *vaddr, dma_addr_t dma_handle,
|
|
unsigned long attrs)
|
|
{
|
|
#ifdef NOT_COHERENT_CACHE
|
|
consistent_free(size, vaddr);
|
|
#else
|
|
free_pages((unsigned long)vaddr, get_order(size));
|
|
#endif
|
|
}
|
|
|
|
static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
|
|
int nents, enum dma_data_direction direction,
|
|
unsigned long attrs)
|
|
{
|
|
struct scatterlist *sg;
|
|
int i;
|
|
|
|
/* FIXME this part of code is untested */
|
|
for_each_sg(sgl, sg, nents, i) {
|
|
sg->dma_address = sg_phys(sg);
|
|
|
|
if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
|
|
continue;
|
|
|
|
__dma_sync(page_to_phys(sg_page(sg)) + sg->offset,
|
|
sg->length, direction);
|
|
}
|
|
|
|
return nents;
|
|
}
|
|
|
|
static int dma_direct_dma_supported(struct device *dev, u64 mask)
|
|
{
|
|
return 1;
|
|
}
|
|
|
|
static inline dma_addr_t dma_direct_map_page(struct device *dev,
|
|
struct page *page,
|
|
unsigned long offset,
|
|
size_t size,
|
|
enum dma_data_direction direction,
|
|
unsigned long attrs)
|
|
{
|
|
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
|
|
__dma_sync(page_to_phys(page) + offset, size, direction);
|
|
return page_to_phys(page) + offset;
|
|
}
|
|
|
|
static inline void dma_direct_unmap_page(struct device *dev,
|
|
dma_addr_t dma_address,
|
|
size_t size,
|
|
enum dma_data_direction direction,
|
|
unsigned long attrs)
|
|
{
|
|
/* There is not necessary to do cache cleanup
|
|
*
|
|
* phys_to_virt is here because in __dma_sync_page is __virt_to_phys and
|
|
* dma_address is physical address
|
|
*/
|
|
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC))
|
|
__dma_sync(dma_address, size, direction);
|
|
}
|
|
|
|
static inline void
|
|
dma_direct_sync_single_for_cpu(struct device *dev,
|
|
dma_addr_t dma_handle, size_t size,
|
|
enum dma_data_direction direction)
|
|
{
|
|
/*
|
|
* It's pointless to flush the cache as the memory segment
|
|
* is given to the CPU
|
|
*/
|
|
|
|
if (direction == DMA_FROM_DEVICE)
|
|
__dma_sync(dma_handle, size, direction);
|
|
}
|
|
|
|
static inline void
|
|
dma_direct_sync_single_for_device(struct device *dev,
|
|
dma_addr_t dma_handle, size_t size,
|
|
enum dma_data_direction direction)
|
|
{
|
|
/*
|
|
* It's pointless to invalidate the cache if the device isn't
|
|
* supposed to write to the relevant region
|
|
*/
|
|
|
|
if (direction == DMA_TO_DEVICE)
|
|
__dma_sync(dma_handle, size, direction);
|
|
}
|
|
|
|
static inline void
|
|
dma_direct_sync_sg_for_cpu(struct device *dev,
|
|
struct scatterlist *sgl, int nents,
|
|
enum dma_data_direction direction)
|
|
{
|
|
struct scatterlist *sg;
|
|
int i;
|
|
|
|
/* FIXME this part of code is untested */
|
|
if (direction == DMA_FROM_DEVICE)
|
|
for_each_sg(sgl, sg, nents, i)
|
|
__dma_sync(sg->dma_address, sg->length, direction);
|
|
}
|
|
|
|
static inline void
|
|
dma_direct_sync_sg_for_device(struct device *dev,
|
|
struct scatterlist *sgl, int nents,
|
|
enum dma_data_direction direction)
|
|
{
|
|
struct scatterlist *sg;
|
|
int i;
|
|
|
|
/* FIXME this part of code is untested */
|
|
if (direction == DMA_TO_DEVICE)
|
|
for_each_sg(sgl, sg, nents, i)
|
|
__dma_sync(sg->dma_address, sg->length, direction);
|
|
}
|
|
|
|
static
|
|
int dma_direct_mmap_coherent(struct device *dev, struct vm_area_struct *vma,
|
|
void *cpu_addr, dma_addr_t handle, size_t size,
|
|
unsigned long attrs)
|
|
{
|
|
#ifdef CONFIG_MMU
|
|
unsigned long user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
|
|
unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
|
|
unsigned long off = vma->vm_pgoff;
|
|
unsigned long pfn;
|
|
|
|
if (off >= count || user_count > (count - off))
|
|
return -ENXIO;
|
|
|
|
#ifdef NOT_COHERENT_CACHE
|
|
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
|
|
pfn = consistent_virt_to_pfn(cpu_addr);
|
|
#else
|
|
pfn = virt_to_pfn(cpu_addr);
|
|
#endif
|
|
return remap_pfn_range(vma, vma->vm_start, pfn + off,
|
|
vma->vm_end - vma->vm_start, vma->vm_page_prot);
|
|
#else
|
|
return -ENXIO;
|
|
#endif
|
|
}
|
|
|
|
const struct dma_map_ops dma_direct_ops = {
|
|
.alloc = dma_direct_alloc_coherent,
|
|
.free = dma_direct_free_coherent,
|
|
.mmap = dma_direct_mmap_coherent,
|
|
.map_sg = dma_direct_map_sg,
|
|
.dma_supported = dma_direct_dma_supported,
|
|
.map_page = dma_direct_map_page,
|
|
.unmap_page = dma_direct_unmap_page,
|
|
.sync_single_for_cpu = dma_direct_sync_single_for_cpu,
|
|
.sync_single_for_device = dma_direct_sync_single_for_device,
|
|
.sync_sg_for_cpu = dma_direct_sync_sg_for_cpu,
|
|
.sync_sg_for_device = dma_direct_sync_sg_for_device,
|
|
};
|
|
EXPORT_SYMBOL(dma_direct_ops);
|
|
|
|
/* Number of entries preallocated for DMA-API debugging */
|
|
#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16)
|
|
|
|
static int __init dma_init(void)
|
|
{
|
|
dma_debug_init(PREALLOC_DMA_DEBUG_ENTRIES);
|
|
|
|
return 0;
|
|
}
|
|
fs_initcall(dma_init);
|