On Fri, Mar 08, 2013 at 05:02:58PM +0100, Jean-Christophe PLAGNIOL-VILLARD
wrote:
> On 13:51 Fri 08 Mar , Johan Hovold wrote:
> > Make sure the RTC and RTT-interrupts are masked at boot by adding a new
> > SOC-initialiser and helpers functions.
> >
> > This fixes hanged boot on all AT91 SOCs but RM9200, for example, after a
> > reset during an RTC-update or if an RTC or RTT-alarm goes off after a
> > non-clean shutdown.
> >
> > 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, 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.
> >
> > Tested on at91sam9263 and at91sam9g45.
> >
> > Signed-off-by: Johan Hovold <jhov...@gmail.com>
> > ---
> > arch/arm/mach-at91/at91rm9200.c | 9 ++++++++
> > arch/arm/mach-at91/at91sam9260.c | 6 ++++++
> > arch/arm/mach-at91/at91sam9261.c | 6 ++++++
> > arch/arm/mach-at91/at91sam9263.c | 7 ++++++
> > arch/arm/mach-at91/at91sam9g45.c | 7 ++++++
> > arch/arm/mach-at91/at91sam9n12.c | 6 ++++++
> > arch/arm/mach-at91/at91sam9rl.c | 7 ++++++
> > arch/arm/mach-at91/at91sam9x5.c | 6 ++++++
> > arch/arm/mach-at91/generic.h | 2 ++
> > arch/arm/mach-at91/include/mach/at91sam9n12.h | 5 +++++
> > arch/arm/mach-at91/include/mach/at91sam9x5.h | 5 +++++
> nack for DT probe te address via DT
Fair enough. I'll respin and add proper DT-support.
> > arch/arm/mach-at91/setup.c | 31
> > +++++++++++++++++++++++++++
> > arch/arm/mach-at91/soc.h | 1 +
> > 13 files changed, 98 insertions(+)
>
> at boot time we can disable all the irq as we need none of them
Yes, but all but the VDDBU-powered-peripheral ones will already have
been disabled at reset. If a buggy bootloader enables something it
should not, then the bootloader should be fixed.
> > diff --git a/arch/arm/mach-at91/at91rm9200.c
> > b/arch/arm/mach-at91/at91rm9200.c
> > index 7aeb473..4651ebb 100644
> > --- a/arch/arm/mach-at91/at91rm9200.c
> > +++ b/arch/arm/mach-at91/at91rm9200.c
> > @@ -325,6 +325,14 @@ static void __init at91rm9200_ioremap_registers(void)
> > at91_ioremap_ramc(0, AT91RM9200_BASE_MC, 256);
> > }
> >
> > +static void __init at91rm9200_sysirq_mask(void)
> > +{
> > + /*
> > + * No need to mask any system interrupts as the RM9200 has no backup
> > + * power and resets all system peripherals at every reset.
> > + */
> > +}
> no need drop it
Ok.
Thanks,
Johan
> > +
> > static void __init at91rm9200_initialize(void)
> > {
> > arm_pm_idle = at91rm9200_idle;
> > @@ -387,5 +395,6 @@ AT91_SOC_START(rm9200)
> > .default_irq_priority = at91rm9200_default_irq_priority,
> > .ioremap_registers = at91rm9200_ioremap_registers,
> > .register_clocks = at91rm9200_register_clocks,
> > + .sysirq_mask = at91rm9200_sysirq_mask,
> > .init = at91rm9200_initialize,
> > AT91_SOC_END
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
