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-rw-r--r--Documentation/DMA-attributes.txt6
1 files changed, 3 insertions, 3 deletions
diff --git a/Documentation/DMA-attributes.txt b/Documentation/DMA-attributes.txt
index e59480db9ee0..cc2450d80310 100644
--- a/Documentation/DMA-attributes.txt
+++ b/Documentation/DMA-attributes.txt
@@ -13,7 +13,7 @@ all pending DMA writes to complete, and thus provides a mechanism to
13strictly order DMA from a device across all intervening busses and 13strictly order DMA from a device across all intervening busses and
14bridges. This barrier is not specific to a particular type of 14bridges. This barrier is not specific to a particular type of
15interconnect, it applies to the system as a whole, and so its 15interconnect, it applies to the system as a whole, and so its
16implementation must account for the idiosyncracies of the system all 16implementation must account for the idiosyncrasies of the system all
17the way from the DMA device to memory. 17the way from the DMA device to memory.
18 18
19As an example of a situation where DMA_ATTR_WRITE_BARRIER would be 19As an example of a situation where DMA_ATTR_WRITE_BARRIER would be
@@ -60,7 +60,7 @@ such mapping is non-trivial task and consumes very limited resources
60Buffers allocated with this attribute can be only passed to user space 60Buffers allocated with this attribute can be only passed to user space
61by calling dma_mmap_attrs(). By using this API, you are guaranteeing 61by calling dma_mmap_attrs(). By using this API, you are guaranteeing
62that you won't dereference the pointer returned by dma_alloc_attr(). You 62that you won't dereference the pointer returned by dma_alloc_attr(). You
63can threat it as a cookie that must be passed to dma_mmap_attrs() and 63can treat it as a cookie that must be passed to dma_mmap_attrs() and
64dma_free_attrs(). Make sure that both of these also get this attribute 64dma_free_attrs(). Make sure that both of these also get this attribute
65set on each call. 65set on each call.
66 66
@@ -82,7 +82,7 @@ to 'device' domain, what synchronizes CPU caches for the given region
82(usually it means that the cache has been flushed or invalidated 82(usually it means that the cache has been flushed or invalidated
83depending on the dma direction). However, next calls to 83depending on the dma direction). However, next calls to
84dma_map_{single,page,sg}() for other devices will perform exactly the 84dma_map_{single,page,sg}() for other devices will perform exactly the
85same sychronization operation on the CPU cache. CPU cache sychronization 85same synchronization operation on the CPU cache. CPU cache synchronization
86might be a time consuming operation, especially if the buffers are 86might be a time consuming operation, especially if the buffers are
87large, so it is highly recommended to avoid it if possible. 87large, so it is highly recommended to avoid it if possible.
88DMA_ATTR_SKIP_CPU_SYNC allows platform code to skip synchronization of 88DMA_ATTR_SKIP_CPU_SYNC allows platform code to skip synchronization of