1. 11 May, 2014 5 commits
  2. 05 May, 2014 5 commits
  3. 02 May, 2014 1 commit
  4. 29 Apr, 2014 1 commit
    • Thomas Gleixner's avatar
      ARM: common: edma: Fix xbar mapping · cf7eb979
      Thomas Gleixner authored
      This is another great example of trainwreck engineering:
      
      commit 2646a0e529 (ARM: edma: Add EDMA crossbar event mux support)
      added support for using EDMA on peripherals which have no direct EDMA
      event mapping.
      
      The code compiles and does not explode in your face, but that's it.
      
      1) Reading an u16 array from an u32 device tree array simply does not
         work. Even if the function is named "edma_of_read_u32_to_s16_array".
      
         It merily calls of_property_read_u16_array. So the resulting 16bit
         array will have every other entry = 0.
      
      2) The DT entry for the xbar registers related to xbar has length 0x10
         instead of the real length: 0xfd0 - 0xf90 = 0x40.
      
         Not a real problem as it does not cross a page boundary, but
         wrong nevertheless.
      
      3) But none of this matters as the mapping never happens:
      
         After reading nonsense edma_of_read_u32_to_s16_array() invalidates
         the first array entry pair, so nobody can ever notice the
         braindamage by immediate explosion.
      
      Seems the QA criteria for this code was solely not to explode when
      someone adds edma-xbar-event-map entries to the DT. Goal achieved,
      congratulations!
      
      Not really helpful if someone wants to use edma on a device which
      requires a xbar mapping.
      
      Fix the issues by:
      
      - annotating the device tree entry with "/bits/ 16" as documented in
        the of_property_read_u16_array kernel doc
      
      - make the size of the xbar register mapping correct
      
      - invalidating the end of the array and not the start
      
      This convoluted mess wants to be completely rewritten as there is no
      point to keep the xbar_chan array memory and the iomapping of the xbar
      regs around forever. Marking the xbar mapped channels as used should
      be done right there.
      
      But that's a different issue and this patch is small enough to make it
      work and allows a simple backport for stable.
      
      Cc: stable@vger.kernel.org # v3.12+
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarSekhar Nori <nsekhar@ti.com>
      cf7eb979
  5. 28 Apr, 2014 1 commit
  6. 26 Apr, 2014 1 commit
  7. 25 Apr, 2014 14 commits
  8. 24 Apr, 2014 12 commits