• Dmitri Vorobiev's avatar
    [MIPS] Malta: Fix software reset on big endian · 84c21e25
    Dmitri Vorobiev authored
    I noticed that the commit f1974653
    (MIPS Tech: Get rid of volatile in core code) broke the software
    reset functionality for MIPS Malta boards in big-endian mode.
    
    According to the MIPS Malta board user's manual, writing the magic
    32-bit GORESET value into the SOFTRES register initiates board soft
    reset. My experimentation has shown that the endianness of the GORESET
    integer should thereby be the same as the endianness, which has been
    set for the CPU itself. The writew() function used to write the magic
    value in the code introduced by the commit mentioned above, however,
    swaps bytes for big-endian kernels and transfers 16 bits instead of 32.
    
    The patch below replaces the writew() function by the __raw_writel()
    routine, which leaves the byte order intact and transfers the whole
    MIPS machine word. Trivial code cleanup (replacing spaces by a tab
    and cutting oversized lines to make checkpatch.pl happy) is also
    included.
    
    The patch was tested using a Malta evaluation board running in both
    BE and LE modes. For both modes, software reset was fully functional
    after the change.
    
    P.S. I suspect that the same commit broke the "standby" functionality
    for MIPS Atlas boards. However, I did not touch the Atlas code as I
    don't have such board at my disposal and also because the linux-mips.org
    Web site claims that Atlas support is scheduled for removal.
    Signed-off-by: default avatarDmitri Vorobiev <dmitri.vorobiev@gmail.com>
    Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
    84c21e25
reset.c 2.1 KB