path: root/include
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authorLinus Torvalds <>2013-11-14 07:55:21 +0900
committerLinus Torvalds <>2013-11-14 07:55:21 +0900
commit8ceafbfa91ffbdbb2afaea5c24ccb519ffb8b587 (patch)
tree98c9ea93362536f1ddd73175b13b7847583350df /include
parent42a2d923cc349583ebf6fdd52a7d35e1c2f7e6bd (diff)
parent26ba47b18318abe7dadbe9294a611c0e932651d8 (diff)
Merge branch 'for-linus-dma-masks' of git://
Pull DMA mask updates from Russell King: "This series cleans up the handling of DMA masks in a lot of drivers, fixing some bugs as we go. Some of the more serious errors include: - drivers which only set their coherent DMA mask if the attempt to set the streaming mask fails. - drivers which test for a NULL dma mask pointer, and then set the dma mask pointer to a location in their module .data section - which will cause problems if the module is reloaded. To counter these, I have introduced two helper functions: - dma_set_mask_and_coherent() takes care of setting both the streaming and coherent masks at the same time, with the correct error handling as specified by the API. - dma_coerce_mask_and_coherent() which resolves the problem of drivers forcefully setting DMA masks. This is more a marker for future work to further clean these locations up - the code which creates the devices really should be initialising these, but to fix that in one go along with this change could potentially be very disruptive. The last thing this series does is prise away some of Linux's addition to "DMA addresses are physical addresses and RAM always starts at zero". We have ARM LPAE systems where all system memory is above 4GB physical, hence having DMA masks interpreted by (eg) the block layers as describing physical addresses in the range 0..DMAMASK fails on these platforms. Santosh Shilimkar addresses this in this series; the patches were copied to the appropriate people multiple times but were ignored. Fixing this also gets rid of some ARM weirdness in the setup of the max*pfn variables, and brings ARM into line with every other Linux architecture as far as those go" * 'for-linus-dma-masks' of git:// (52 commits) ARM: 7805/1: mm: change max*pfn to include the physical offset of memory ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations ARM: 7795/1: mm: dma-mapping: Add dma_max_pfn(dev) helper function ARM: 7794/1: block: Rename parameter dma_mask to max_addr for blk_queue_bounce_limit() ARM: DMA-API: better handing of DMA masks for coherent allocations ARM: 7857/1: dma: imx-sdma: setup dma mask DMA-API: firmware/google/gsmi.c: avoid direct access to DMA masks DMA-API: dcdbas: update DMA mask handing DMA-API: dma: edma.c: no need to explicitly initialize DMA masks DMA-API: usb: musb: use platform_device_register_full() to avoid directly messing with dma masks DMA-API: crypto: remove last references to 'static struct device *dev' DMA-API: crypto: fix ixp4xx crypto platform device support DMA-API: others: use dma_set_coherent_mask() DMA-API: staging: use dma_set_coherent_mask() DMA-API: usb: use new dma_coerce_mask_and_coherent() DMA-API: usb: use dma_set_coherent_mask() DMA-API: parport: parport_pc.c: use dma_coerce_mask_and_coherent() DMA-API: net: octeon: use dma_coerce_mask_and_coherent() DMA-API: net: nxp/lpc_eth: use dma_coerce_mask_and_coherent() ...
Diffstat (limited to 'include')
2 files changed, 31 insertions, 2 deletions
diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
index 43ec7e2..682df0e 100644
--- a/include/linux/amba/bus.h
+++ b/include/linux/amba/bus.h
@@ -30,7 +30,6 @@ struct amba_device {
struct device dev;
struct resource res;
struct clk *pclk;
- u64 dma_mask;
unsigned int periphid;
unsigned int irq[AMBA_NR_IRQS];
@@ -131,7 +130,6 @@ struct amba_device name##_device = { \
struct amba_device name##_device = { \
.dev = __AMBA_DEV(busid, data, ~0ULL), \
.res = DEFINE_RES_MEM(base, SZ_4K), \
- .dma_mask = ~0ULL, \
.irq = irqs, \
.periphid = id, \
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 3a8d0a2..fd4aee2 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -97,6 +97,30 @@ static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
+ * Set both the DMA mask and the coherent DMA mask to the same thing.
+ * Note that we don't check the return value from dma_set_coherent_mask()
+ * as the DMA API guarantees that the coherent DMA mask can be set to
+ * the same or smaller than the streaming DMA mask.
+ */
+static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
+ int rc = dma_set_mask(dev, mask);
+ if (rc == 0)
+ dma_set_coherent_mask(dev, mask);
+ return rc;
+ * Similar to the above, except it deals with the case where the device
+ * does not have dev->dma_mask appropriately setup.
+ */
+static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
+ dev->dma_mask = &dev->coherent_dma_mask;
+ return dma_set_mask_and_coherent(dev, mask);
extern u64 dma_get_required_mask(struct device *dev);
static inline unsigned int dma_get_max_seg_size(struct device *dev)
@@ -129,6 +153,13 @@ static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
return -EIO;
+#ifndef dma_max_pfn
+static inline unsigned long dma_max_pfn(struct device *dev)
+ return *dev->dma_mask >> PAGE_SHIFT;
static inline void *dma_zalloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)