linux/arch/blackfin/include/asm/dma-mapping.h
Sonic Zhang a3a6a59019 Blackfin: dma-mapping: fix thinko in constant optimization
Make sure the non-constant version of the dma_sync functions actually
complete instead of recursively calling itself forever.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-03-09 00:30:46 -05:00

196 lines
5.4 KiB
C

/*
* Copyright 2004-2009 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#ifndef _BLACKFIN_DMA_MAPPING_H
#define _BLACKFIN_DMA_MAPPING_H
#include <asm/cacheflush.h>
struct scatterlist;
void *dma_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp);
void dma_free_coherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle);
/*
* Now for the API extensions over the pci_ one
*/
#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
#define dma_supported(d, m) (1)
#define dma_get_cache_alignment() (32)
#define dma_is_consistent(d, h) (1)
static inline int
dma_set_mask(struct device *dev, u64 dma_mask)
{
if (!dev->dma_mask || !dma_supported(dev, dma_mask))
return -EIO;
*dev->dma_mask = dma_mask;
return 0;
}
static inline int
dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
return 0;
}
extern void
__dma_sync(dma_addr_t addr, size_t size, enum dma_data_direction dir);
static inline void
__dma_sync_inline(dma_addr_t addr, size_t size, enum dma_data_direction dir)
{
switch (dir) {
case DMA_NONE:
BUG();
case DMA_TO_DEVICE: /* writeback only */
flush_dcache_range(addr, addr + size);
break;
case DMA_FROM_DEVICE: /* invalidate only */
case DMA_BIDIRECTIONAL: /* flush and invalidate */
/* Blackfin has no dedicated invalidate (it includes a flush) */
invalidate_dcache_range(addr, addr + size);
break;
}
}
static inline void
_dma_sync(dma_addr_t addr, size_t size, enum dma_data_direction dir)
{
if (__builtin_constant_p(dir))
__dma_sync_inline(addr, size, dir);
else
__dma_sync(addr, size, dir);
}
/*
* Map a single buffer of the indicated size for DMA in streaming mode.
* The 32-bit bus address to use is returned.
*
* Once the device is given the dma address, the device owns this memory
* until either pci_unmap_single or pci_dma_sync_single is performed.
*/
static inline dma_addr_t
dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction dir)
{
_dma_sync((dma_addr_t)ptr, size, dir);
return (dma_addr_t) ptr;
}
static inline dma_addr_t
dma_map_page(struct device *dev, struct page *page,
unsigned long offset, size_t size,
enum dma_data_direction dir)
{
return dma_map_single(dev, page_address(page) + offset, size, dir);
}
/*
* Unmap a single streaming mode DMA translation. The dma_addr and size
* must match what was provided for in a previous pci_map_single call. All
* other usages are undefined.
*
* After this call, reads by the cpu to the buffer are guarenteed to see
* whatever the device wrote there.
*/
static inline void
dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir)
{
BUG_ON(!valid_dma_direction(dir));
}
static inline void
dma_unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction dir)
{
dma_unmap_single(dev, dma_addr, size, dir);
}
/*
* Map a set of buffers described by scatterlist in streaming
* mode for DMA. This is the scather-gather version of the
* above pci_map_single interface. Here the scatter gather list
* elements are each tagged with the appropriate dma address
* and length. They are obtained via sg_dma_{address,length}(SG).
*
* NOTE: An implementation may be able to use a smaller number of
* DMA address/length pairs than there are SG table elements.
* (for example via virtual mapping capabilities)
* The routine returns the number of addr/length pairs actually
* used, at most nents.
*
* Device ownership issues as mentioned above for pci_map_single are
* the same here.
*/
extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir);
/*
* Unmap a set of streaming mode DMA translations.
* Again, cpu read rules concerning calls here are the same as for
* pci_unmap_single() above.
*/
static inline void
dma_unmap_sg(struct device *dev, struct scatterlist *sg,
int nhwentries, enum dma_data_direction dir)
{
BUG_ON(!valid_dma_direction(dir));
}
static inline void
dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t handle,
unsigned long offset, size_t size,
enum dma_data_direction dir)
{
BUG_ON(!valid_dma_direction(dir));
}
static inline void
dma_sync_single_range_for_device(struct device *dev, dma_addr_t handle,
unsigned long offset, size_t size,
enum dma_data_direction dir)
{
_dma_sync(handle + offset, size, dir);
}
static inline void
dma_sync_single_for_cpu(struct device *dev, dma_addr_t handle, size_t size,
enum dma_data_direction dir)
{
dma_sync_single_range_for_cpu(dev, handle, 0, size, dir);
}
static inline void
dma_sync_single_for_device(struct device *dev, dma_addr_t handle, size_t size,
enum dma_data_direction dir)
{
dma_sync_single_range_for_device(dev, handle, 0, size, dir);
}
static inline void
dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir)
{
BUG_ON(!valid_dma_direction(dir));
}
extern void
dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir);
static inline void
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
enum dma_data_direction dir)
{
_dma_sync((dma_addr_t)vaddr, size, dir);
}
#endif /* _BLACKFIN_DMA_MAPPING_H */