linux/arch
Johan Hovold 6de714c21a 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
2013-11-15 12:13:33 +01:00
..
alpha Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
arc Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
arm ARM: at91: fix hanged boot due to early rtc-interrupt 2013-11-15 12:13:33 +01:00
arm64 arm64: Widen hwcap to be 64 bit 2013-09-20 09:56:07 +01:00
avr32 Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
blackfin Merge branch 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2013-09-13 07:31:38 -07:00
c6x Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
cris Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
frv Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
h8300 Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
hexagon Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
ia64 Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
m32r Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
m68k Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
metag Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
microblaze Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
mips MIPS: mm: Move some checks out of 'for' loop in DMA operations 2013-09-25 17:05:44 +02:00
mn10300 Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
openrisc openrisc: clean-up prom.h 2013-09-24 21:12:27 -05:00
parisc Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
powerpc powerpc/pseries: Do not start secondaries in Open Firmware 2013-09-25 14:19:00 +10:00
s390 s390: enable ARCH_USE_CMPXCHG_LOCKREF 2013-09-28 12:46:29 +02:00
score Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
sh Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
sparc Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
tile tile: remove stray blank space 2013-09-16 15:47:32 -04:00
um Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
unicore32 Remove GENERIC_HARDIRQ config option 2013-09-13 15:09:52 +02:00
x86 Merge branches 'sched-urgent-for-linus', 'timers-urgent-for-linus' and 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-09-28 14:22:17 -07:00
xtensa Xtensa patchset for v3.12 2013-09-13 10:57:48 -07:00
.gitignore
Kconfig mutex: replace CONFIG_HAVE_ARCH_MUTEX_CPU_RELAX with simple ifdef 2013-09-28 12:46:21 +02:00