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author | Johan Hovold <jhovold@gmail.com> | 2013-10-16 09:56:15 (GMT) |
---|---|---|
committer | Nicolas Ferre <nicolas.ferre@atmel.com> | 2013-11-15 11:13:33 (GMT) |
commit | 94c4c79f2f1acca6e69a50bff5a7d9027509c16b (patch) | |
tree | 85b5fdb02f99edb8b8f4368ea932c4d149fc9e1f /arch/arm/mach-at91/generic.h | |
parent | 6de714c21a8ea315fffba6a93bbe537f4c1bf4f0 (diff) | |
download | linux-94c4c79f2f1acca6e69a50bff5a7d9027509c16b.tar.xz |
ARM: at91: fix hanged boot due to early rtt-interrupt
Make sure the RTT-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 RTT, for example, if an
RTT-alarm goes off after a non-clean 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/generic.h')
-rw-r--r-- | arch/arm/mach-at91/generic.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/generic.h b/arch/arm/mach-at91/generic.h index 80269bd..26dee3c 100644 --- a/arch/arm/mach-at91/generic.h +++ b/arch/arm/mach-at91/generic.h @@ -35,6 +35,7 @@ extern int __init at91_aic_of_init(struct device_node *node, extern int __init at91_aic5_of_init(struct device_node *node, struct device_node *parent); extern void __init at91_sysirq_mask_rtc(u32 rtc_base); +extern void __init at91_sysirq_mask_rtt(u32 rtt_base); /* Timer */ |