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authorStephen Rothwell <sfr@canb.auug.org.au>2011-07-25 13:59:46 -0400
committerTrond Myklebust <Trond.Myklebust@netapp.com>2011-07-25 14:53:52 -0400
commit5f00bcb38ef9a980a33c6dbdc0044964b05f22dd (patch)
tree3175fb9375aecb50bde1be0bf4fa8aa8155131d6 /arch/arm/mm/dma-mapping.c
parent34006cee28f7344f9557a4be3816c7891b1bbab1 (diff)
parentb6844e8f64920cdee620157252169ba63afb0c89 (diff)
Merge branch 'master' into devel and apply fixup from Stephen Rothwell:
vfs/nfs: fixup for nfs_open_context change Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
-rw-r--r--arch/arm/mm/dma-mapping.c35
1 files changed, 32 insertions, 3 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 82a093cee09..0a0a1e7c20d 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -25,9 +25,11 @@
#include <asm/tlbflush.h>
#include <asm/sizes.h>
+#include "mm.h"
+
static u64 get_coherent_dma_mask(struct device *dev)
{
- u64 mask = ISA_DMA_THRESHOLD;
+ u64 mask = (u64)arm_dma_limit;
if (dev) {
mask = dev->coherent_dma_mask;
@@ -41,10 +43,10 @@ static u64 get_coherent_dma_mask(struct device *dev)
return 0;
}
- if ((~mask) & ISA_DMA_THRESHOLD) {
+ if ((~mask) & (u64)arm_dma_limit) {
dev_warn(dev, "coherent DMA mask %#llx is smaller "
"than system GFP_DMA mask %#llx\n",
- mask, (unsigned long long)ISA_DMA_THRESHOLD);
+ mask, (u64)arm_dma_limit);
return 0;
}
}
@@ -657,6 +659,33 @@ void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
}
EXPORT_SYMBOL(dma_sync_sg_for_device);
+/*
+ * Return whether the given device DMA address mask can be supported
+ * properly. For example, if your device can only drive the low 24-bits
+ * during bus mastering, then you would pass 0x00ffffff as the mask
+ * to this function.
+ */
+int dma_supported(struct device *dev, u64 mask)
+{
+ if (mask < (u64)arm_dma_limit)
+ return 0;
+ return 1;
+}
+EXPORT_SYMBOL(dma_supported);
+
+int dma_set_mask(struct device *dev, u64 dma_mask)
+{
+ if (!dev->dma_mask || !dma_supported(dev, dma_mask))
+ return -EIO;
+
+#ifndef CONFIG_DMABOUNCE
+ *dev->dma_mask = dma_mask;
+#endif
+
+ return 0;
+}
+EXPORT_SYMBOL(dma_set_mask);
+
#define PREALLOC_DMA_DEBUG_ENTRIES 4096
static int __init dma_debug_do_init(void)