diff options
author | Johan Hovold <jhovold@gmail.com> | 2013-10-16 11:56:14 +0200 |
---|---|---|
committer | Nicolas Ferre <nicolas.ferre@atmel.com> | 2013-11-15 12:13:33 +0100 |
commit | 6de714c21a8ea315fffba6a93bbe537f4c1bf4f0 (patch) | |
tree | c3e0e05dfb0a222220516dd54e4a4f35f817355e /arch/arm/mach-at91/include/mach/at91sam9x5.h | |
parent | 15c03dd4859ab16f9212238f29dd315654aa94f6 (diff) |
ARM: at91: fix hanged boot due to early rtc-interrupt
Make sure the RTC-interrupts are masked at boot by adding a new helper
function to be used at SOC-init.
This fixes hanged boot on all AT91 SOCs with an RTC (but RM9200), for
example, after a reset during an RTC-update or if an RTC-alarm goes off
after shutdown (e.g. when using RTC wakeup).
The RTC and RTT-peripherals are powered by backup power (VDDBU) (on all
AT91 SOCs but RM9200) and are not reset on wake-up, user, watchdog or
software reset. This means that their interrupts may be enabled during
early boot if, for example, they where not disabled during a previous
shutdown (e.g. due to a buggy driver or a non-clean shutdown such as a
user reset). Furthermore, an RTC or RTT-alarm may also be active.
The RTC and RTT-interrupts use the shared system-interrupt line, which
is also used by the PIT, and if an interrupt occurs before a handler
(e.g. RTC-driver) has been installed this leads to the system interrupt
being disabled and prevents the system from booting.
Note that when boot hangs due to an early RTC or RTT-interrupt, the only
way to get the system to start again is to remove the backup power (e.g.
battery) or to disable the interrupt manually from the bootloader. In
particular, a user reset is not sufficient.
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: stable@vger.kernel.org # 3.11.x
Diffstat (limited to 'arch/arm/mach-at91/include/mach/at91sam9x5.h')
-rw-r--r-- | arch/arm/mach-at91/include/mach/at91sam9x5.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/include/mach/at91sam9x5.h b/arch/arm/mach-at91/include/mach/at91sam9x5.h index c75ee19b58d3..2fc76c49e97c 100644 --- a/arch/arm/mach-at91/include/mach/at91sam9x5.h +++ b/arch/arm/mach-at91/include/mach/at91sam9x5.h @@ -55,6 +55,11 @@ #define AT91SAM9X5_BASE_USART2 0xf8024000 /* + * System Peripherals + */ +#define AT91SAM9X5_BASE_RTC 0xfffffeb0 + +/* * Internal Memory. */ #define AT91SAM9X5_SRAM_BASE 0x00300000 /* Internal SRAM base address */ |