Once the Davinci watchdog has been enabled, the timeout value cannot be changed. If the timeout in use is long, it can take a long time for card to reset. By writing an invalid service key, we can trigger an immediate reset.
Signed-off-by: Thomas Lange thomas@corelatus.se --- cpu/arm926ejs/davinci/reset.S | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/cpu/arm926ejs/davinci/reset.S b/cpu/arm926ejs/davinci/reset.S index a687d44..ba0a7c3 100644 --- a/cpu/arm926ejs/davinci/reset.S +++ b/cpu/arm926ejs/davinci/reset.S @@ -50,6 +50,10 @@ reset_cpu: str r1, [r0] ldr r1, WDTCR_VAL2 str r1, [r0] + /* Write an invalid value to the WDKEY field to trigger + * an immediate watchdog reset */ + mov r1, $0x4000 + str r1, [r0] nop nop nop