lkml.org 
[lkml]   [2011]   [Dec]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH 13/14] common: DMA-mapping: add WRITE_COMBINE attribute
DMA_ATTR_WRITE_COMBINE specifies that writes to the mapping may be
buffered to improve performance. It will be used by the replacement for
ARM/ARV32 specific dma_alloc_writecombine() function.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
Documentation/DMA-attributes.txt | 10 ++++++++++
include/linux/dma-attrs.h | 1 +
2 files changed, 11 insertions(+), 0 deletions(-)
diff --git a/Documentation/DMA-attributes.txt b/Documentation/DMA-attributes.txt
index b768cc0..811a5d4 100644
--- a/Documentation/DMA-attributes.txt
+++ b/Documentation/DMA-attributes.txt
@@ -31,3 +31,13 @@ may be weakly ordered, that is that reads and writes may pass each other.
Since it is optional for platforms to implement DMA_ATTR_WEAK_ORDERING,
those that do not will simply ignore the attribute and exhibit default
behavior.
+
+DMA_ATTR_WRITE_COMBINE
+----------------------
+
+DMA_ATTR_WRITE_COMBINE specifies that writes to the mapping may be
+buffered to improve performance.
+
+Since it is optional for platforms to implement DMA_ATTR_WRITE_COMBINE,
+those that do not will simply ignore the attribute and exhibit default
+behavior.
diff --git a/include/linux/dma-attrs.h b/include/linux/dma-attrs.h
index 71ad34e..ada61e1 100644
--- a/include/linux/dma-attrs.h
+++ b/include/linux/dma-attrs.h
@@ -13,6 +13,7 @@
enum dma_attr {
DMA_ATTR_WRITE_BARRIER,
DMA_ATTR_WEAK_ORDERING,
+ DMA_ATTR_WRITE_COMBINE,
DMA_ATTR_MAX,
};

--
1.7.1.569.g6f426


\
 
 \ /
  Last update: 2011-12-23 13:31    [W:0.229 / U:0.232 seconds]
©2003-2014 Jasper Spaans. Advertise on this site