Merge branch 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm

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://git.linaro.org/people/rmk/linux-arm: (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()
  ...

2 files changed, 31 insertions, 2 deletions

diff --git a/include/linux/amba/bus.h b/include/linux/amba/bus.h
index 43ec7e247a80..682df0e1954a 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 3a8d0a2af607..fd4aee29ad10 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)
 }
 #endif
 
+/*
+ * 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;
+}
+#endif
+
 static inline void *dma_zalloc_coherent(struct device *dev, size_t size,
                                         dma_addr_t *dma_handle, gfp_t flag)
 {