diff options
Diffstat (limited to 'Documentation/core-api/dma-attributes.rst')
| -rw-r--r-- | Documentation/core-api/dma-attributes.rst | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/Documentation/core-api/dma-attributes.rst b/Documentation/core-api/dma-attributes.rst index 0bdc2be65e57..1d7bfad73b1c 100644 --- a/Documentation/core-api/dma-attributes.rst +++ b/Documentation/core-api/dma-attributes.rst @@ -148,3 +148,12 @@ DMA_ATTR_MMIO is appropriate. For architectures that require cache flushing for DMA coherence DMA_ATTR_MMIO will not perform any cache flushing. The address provided must never be mapped cacheable into the CPU. + +DMA_ATTR_CPU_CACHE_CLEAN +------------------------ + +This attribute indicates the CPU will not dirty any cacheline overlapping this +DMA_FROM_DEVICE/DMA_BIDIRECTIONAL buffer while it is mapped. This allows +multiple small buffers to safely share a cacheline without risk of data +corruption, suppressing DMA debug warnings about overlapping mappings. +All mappings sharing a cacheline should have this attribute. |