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  1. Nov 07, 2017
  2. Nov 02, 2017
  3. Nov 01, 2017
    • Douglas Anderson's avatar
      mmc: dw_mmc: Fix the DTO timeout calculation · 9d9491a7
      Douglas Anderson authored
      Just like the CTO timeout calculation introduced recently, the DTO
      timeout calculation was incorrect.  It used "bus_hz" but, as far as I
      can tell, it's supposed to use the card clock.  Let's account for the
      div value, which is documented as 2x the value stored in the register,
      or 1 if the register is 0.
      
      NOTE: This was likely not terribly important until commit 16a34574
      ("mmc: dw_mmc: remove the quirks flags") landed because "DIV" is
      documented on Rockchip SoCs (the ones that used to define the quirk)
      to always be 0 or 1.  ...and, in fact, it's documented to only be 1
      with EMMC in 8-bit DDR52 mode.  Thus before the quirk was applied to
      everyone it was mostly OK to ignore the DIV value.
      
      I haven't personally observed any problems that are fixed by this
      patch but I also haven't tested this anywhere with a DIV other an 0.
      AKA: this problem was found simply by code inspection and I have no
      failing test cases that are fixed by it.  Presumably this could fix
      real bugs for someone out there, though.
      
      Fixes: 16a34574
      
       ("mmc: dw_mmc: remove the quirks flags")
      Signed-off-by: default avatarDouglas Anderson <dianders@chromium.org>
      Reviewed-by: default avatarShawn Lin <shawn.lin@rock-chips.com>
      Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
      9d9491a7
  4. Oct 30, 2017