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authorLinus Torvalds <torvalds@linux-foundation.org>2011-07-24 10:20:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-07-24 10:20:54 -0700
commitb6844e8f64920cdee620157252169ba63afb0c89 (patch)
tree339a447f4d1b6b2a447d10d24de227ddfbd4cc65 /arch/arm/mm/dma-mapping.c
parent2f175074e6811974ee77ddeb026f4d21aa3eca4d (diff)
parent3ad55155b222f2a901405dea20ff7c68828ecd92 (diff)
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (237 commits) ARM: 7004/1: fix traps.h compile warnings ARM: 6998/2: kernel: use proper memory barriers for bitops ARM: 6997/1: ep93xx: increase NR_BANKS to 16 for support of 128MB RAM ARM: Fix build errors caused by adding generic macros ARM: CPU hotplug: ensure we migrate all IRQs off a downed CPU ARM: CPU hotplug: pass in proper affinity mask on IRQ migration ARM: GIC: avoid routing interrupts to offline CPUs ARM: CPU hotplug: fix abuse of irqdesc->node ARM: 6981/2: mmci: adjust calculation of f_min ARM: 7000/1: LPAE: Use long long printk format for displaying the pud ARM: 6999/1: head, zImage: Always Enter the kernel in ARM state ARM: btc: avoid invalidating the branch target cache on kernel TLB maintanence ARM: ARM_DMA_ZONE_SIZE is no more ARM: mach-shark: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ARM: mach-sa1100: move ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ARM: mach-realview: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ARM: mach-pxa: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ARM: mach-ixp4xx: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ARM: mach-h720x: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ARM: mach-davinci: move from ARM_DMA_ZONE_SIZE to mdesc->dma_zone_size ...
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 82a093cee09a..0a0a1e7c20d2 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)