Gitweb:
http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=7f8e33546d17c7d8849be3a6623c3b6b3c9b588b
Commit: 7f8e33546d17c7d8849be3a6623c3b6b3c9b588b
Parent: 56660faf9e8088542e85207df45fb9c5f4dd3909
Author: Russell King <[EMAIL PROTECTED]>
AuthorDate: Tue Feb 6 17:29:53 2007 +0000
Committer: Russell King <[EMAIL PROTECTED]>
CommitDate: Thu Feb 8 14:49:37 2007 +0000
[ARM] Don't call consistent_sync() for DMA coherent memory
Memory allocated by the coherent memory allocators will be marked
uncacheable, which means it's pointless calling consistent_sync()
to perform cache maintainence on this memory; it's just a waste of
CPU cycles.
Moreover, with the (subsequent) merge of outer cache support, it
actually breaks things to call consistent_sync() on anything but
direct-mapped memory.
Signed-off-by: Russell King <[EMAIL PROTECTED]>
---
arch/arm/common/dmabounce.c | 13 ++++++++++---
1 files changed, 10 insertions(+), 3 deletions(-)
diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c
index 2e635b8..272702a 100644
--- a/arch/arm/common/dmabounce.c
+++ b/arch/arm/common/dmabounce.c
@@ -281,10 +281,14 @@ map_single(struct device *dev, void *ptr, size_t size,
ptr = buf->safe;
dma_addr = buf->safe_dma_addr;
+ } else {
+ /*
+ * We don't need to sync the DMA buffer since
+ * it was allocated via the coherent allocators.
+ */
+ consistent_sync(ptr, size, dir);
}
- consistent_sync(ptr, size, dir);
-
return dma_addr;
}
@@ -397,7 +401,10 @@ sync_single(struct device *dev, dma_addr_t dma_addr,
size_t size,
default:
BUG();
}
- consistent_sync(buf->safe, size, dir);
+ /*
+ * No need to sync the safe buffer - it was allocated
+ * via the coherent allocators.
+ */
} else {
consistent_sync(dma_to_virt(dev, dma_addr), size, dir);
}
-
To unsubscribe from this list: send the line "unsubscribe git-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
