• Magnus Damm's avatar
    ARM: mach-shmobile: INTC interrupt priority level demux fix · 1cf215a5
    Magnus Damm authored
    
    
    Fix interrupt priority level handling on SH-Mobile ARM.
    
    SH-Mobile ARM platforms using multiple interrupt priority
    levels need this patch to fix a potential dead lock that
    may occur if multiple interrupts with different levels
    are pending simultaneously.
    
    The default INTC configuration is to use the same priority
    level for all interrupts, so this issue does not trigger by
    default. It is however common for board code to override the
    interrupt priority for certain interrupt sources depending
    on the application. Without this fix such boards may lock up.
    
    In detail, this patch updates the INTC code in entry-macro.S
    to make sure that the INTLVLA register gets set as expected.
    
    To trigger this bug modify the board specific code to adjust
    the interrupt priority level for the ethernet chip. After
    changing the priority level simply use flood ping to drown
    the board with interrupts.
    
    This patch applies to INTCA-based processors such as sh7372,
    sh7377 and sh7372. GIC-based processors are not affected.
    
    Suitable for v2.6.37-rc and stable from v2.6.34 to v2.6.36.
    
    Cc: stable@kernel.org
    Signed-off-by: default avatarMagnus Damm <damm@opensource.se>
    Tested-by: default avatarKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
    Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
    1cf215a5