diff options
| author | Haavard Skinnemoen <hskinnemoen@atmel.com> | 2007-03-20 14:41:13 +0100 |
|---|---|---|
| committer | Haavard Skinnemoen <hskinnemoen@atmel.com> | 2007-05-09 08:48:39 +0200 |
| commit | a492dbb9e3d04db138f2841648d1904d38a5295d (patch) | |
| tree | 6b2b433941c8a97c175b827796d47824831a7506 /arch | |
| parent | e89b064a4fd18b9c57b7aecbe7101d782759cf81 (diff) | |
[AVR32] Implement dma_{alloc,free}_writecombine()
Implement dma_alloc_writecombine() and its dma_free_writecombine()
counterpart. These will do basically the same thing as
dma_alloc_coherent() except that the virtual mapping will allow
write buffering, causing better performance for certain use cases
like frame buffers.
The same API is already available on ARM.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/avr32/mm/dma-coherent.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/arch/avr32/mm/dma-coherent.c b/arch/avr32/mm/dma-coherent.c index b68d669f823..099212d4567 100644 --- a/arch/avr32/mm/dma-coherent.c +++ b/arch/avr32/mm/dma-coherent.c @@ -112,16 +112,21 @@ void dma_free_coherent(struct device *dev, size_t size, } EXPORT_SYMBOL(dma_free_coherent); -#if 0 void *dma_alloc_writecombine(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp) { struct page *page; + dma_addr_t phys; page = __dma_alloc(dev, size, handle, gfp); + if (!page) + return NULL; + + phys = page_to_phys(page); + *handle = phys; /* Now, map the page into P3 with write-combining turned on */ - return __ioremap(page_to_phys(page), size, _PAGE_BUFFER); + return __ioremap(phys, size, _PAGE_BUFFER); } EXPORT_SYMBOL(dma_alloc_writecombine); @@ -132,8 +137,7 @@ void dma_free_writecombine(struct device *dev, size_t size, iounmap(cpu_addr); - page = bus_to_page(handle); + page = phys_to_page(handle); __dma_free(dev, size, page, handle); } EXPORT_SYMBOL(dma_free_writecombine); -#endif |