FUJITA Tomonori wrote: > On Fri, 12 Mar 2010 20:12:39 +0100 > Albert Herranz <albert_herranz@xxxxxxxx> wrote: > >> The current SWIOTLB code does not support NOT_COHERENT_CACHE platforms. >> This patch adds support for NOT_COHERENT_CACHE platforms to SWIOTLB by >> adding two platform specific functions swiotlb_dma_sync_page() and >> swiotlb_dma_sync() which can be used to explicitly manage cache coherency. >> >> On PowerPC these functions are mapped to their corresponding >> __dma_sync_page() and __dma_sync() functions. >> On other architectures using SWIOTLB these functions are optimized out. >> >> This will be used later to support SWIOTLB on the Nintendo Wii video game >> console. >> >> CC: linuxppc-dev@xxxxxxxxxxxxxxxx >> CC: linux-kernel@xxxxxxxxxxxxxxx >> CC: x86@xxxxxxxxxx >> CC: linux-ia64@xxxxxxxxxxxxxxx >> Signed-off-by: Albert Herranz <albert_herranz@xxxxxxxx> >> --- >> arch/ia64/include/asm/swiotlb.h | 10 ++++++++++ >> arch/powerpc/include/asm/swiotlb.h | 3 +++ >> arch/x86/include/asm/swiotlb.h | 10 ++++++++++ >> lib/swiotlb.c | 30 ++++++++++++++++++++++++------ >> 4 files changed, 47 insertions(+), 6 deletions(-) > > Why can't you use dma_sync_single_* instead of inventing new > swiotlb sync functions? > At least on PowerPC, the DMA ops are per-device hooks. We attach the swiotlb DMA ops functions to those hooks when we are using swiotlb. So calling dma_sync_single_*() would end up calling swiotlb_sync_single_*() which is not what we want. Thanks, Albert -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
