mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-04 21:46:39 +07:00
a227fb92a0
This patch removes the need for the offset parameter in dma bounce functions. This is required to let dma-mapping framework on ARM architecture to use common, generic dma_map_ops based dma-mapping helpers. Background and more detailed explaination: dma_*_range_* functions are available from the early days of the dma mapping api. They are the correct way of doing a partial syncs on the buffer (usually used by the network device drivers). This patch changes only the internal implementation of the dma bounce functions to let them tunnel through dma_map_ops structure. The driver api stays unchanged, so driver are obliged to call dma_*_range_* functions to keep code clean and easy to understand. The only drawback from this patch is reduced detection of the dma api abuse. Let us consider the following code: dma_addr = dma_map_single(dev, ptr, 64, DMA_TO_DEVICE); dma_sync_single_range_for_cpu(dev, dma_addr+16, 0, 32, DMA_TO_DEVICE); Without the patch such code fails, because dma bounce code is unable to find the bounce buffer for the given dma_address. After the patch the above sync call will be equivalent to: dma_sync_single_range_for_cpu(dev, dma_addr, 16, 32, DMA_TO_DEVICE); which succeeds. I don't consider this as a real problem, because DMA API abuse should be caught by debug_dma_* function family. This patch lets us to simplify the internal low-level implementation without chaning the driver visible API. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> Tested-By: Subash Patel <subash.ramaswamy@linaro.org> |
||
|---|---|---|
| .. | ||
| dmabounce.c | ||
| gic.c | ||
| icst.c | ||
| it8152.c | ||
| Kconfig | ||
| locomo.c | ||
| Makefile | ||
| sa1111.c | ||
| scoop.c | ||
| sharpsl_param.c | ||
| timer-sp.c | ||
| uengine.c | ||
| via82c505.c | ||
| vic.c | ||