• Alessandro Rubini's avatar
    bugfix: kernel: use more relaxed nand timings · bb56d5b5
    Alessandro Rubini authored
    We used the timing from the g45ek, but ours is slower. Actually, ours
    is slower only in 16-bit mode, and has the same timing when used in
    8-bit mode.
    
    Our timing setup was outside of the allowed specification, and resulted
    in random and unreproducible failures.  The "visible" effect is
    that reading 100MB takes 13.4s instead of 11.4s, measured with:
    
      time dd bs=1k count=102400 < /dev/mtd1 > /dev/null
    
    You can try another, still slower, setup just by hand, like this
    (in this order):
    
       devmem 0xffffe83c w 0x00051003
       devmem 0xffffe838 w 0x000f000f
       devmem 0xffffe830 w 0x04060406
    
    but the current settings (41003, 000c000c, 02040204) are alread within
    specification.
    Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
    bb56d5b5
0012-sam9m10g45ek-for-wrs-more-relaxed-nand-timings.patch 1.27 KB