• Linus Torvalds's avatar
    Merge branch 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm · 8ceafbfa
    Linus Torvalds authored
    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()
      ...
    8ceafbfa
atmel-pcm.c 3.29 KB