[PATCH 1/3] ARM: OMAP: timer: allow gp timer clock-event to be used on both cpus

[Shilimkar, Santosh]

On Fri, Aug 3, 2012 at 2:00 PM, Koen Kooi <koen at dominion.thruhere.net> wrote:
>
> Op 3 aug. 2012, om 09:21 heeft Koen Kooi <koen at dominion.thruhere.net> het volgende geschreven:
>
>>
>> Op 3 aug. 2012, om 09:16 heeft Daniel Mack <zonque at gmail.com> het volgende geschreven:
>>
>>> On 30.03.2012 15:27, Santosh Shilimkar wrote:
>>>> For coupled cpuidle to work when both cpus are active, it needs a global timer
>>>> that can handle events for both cpus.  This timer is used as the broadcast
>>>> clock-event when the per-cpu timer hardware stop in low power states.
>>>> Set the cpumask of clockevent_gpt to all cpus, set the rating correctly, and
>>>> set the irq to allow the clockevent core to determine the affinity of the
>>>> timer.
>>>
>>> These patches made it to mainline now, shortly befor 3.6-rc1, and it
>>> breaks boot on my AM33xx board.
>>>
>>> Once I revert 1/3, the board boots again but crashes with the Ooops
>>> below. With the entire series reverted, everything works again as
>>> expected. Any idea?
>>>
>>> The upstream commit ids are
>>>
>>> 11d6ec2e "ARM: OMAP: timer: allow gp timer clock-event to be used on
>>> both cpus"
>>> 5b4d5bcc "ARM: OMAP4: CPUidle: add synchronization for coupled idle states"
>>> b93d70ae "ARM: OMAP4: CPUidle: Open broadcast clock-event device."
>>
>> I've had boot problems with cpuidle enabled as well, what happens if you disable it? Is the revert still needed in that case?
>
> To answer my own question: No, the reverts aren't needed if you disable cpuidle.

This is really strange since CPUIDLE code is really OMAP4 specific.
obj-$(CONFIG_ARCH_OMAP4)                += cpuidle44xx.o

May be omap2plus build some how the code gets executed on AMXX

Can you try below and see if the boot with CPUIDLE enabled goes away on
AMXX

diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
index ea24174..195e756 100644
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c
@@ -147,6 +147,9 @@ int __init omap4_pm_init(void)
        struct clockdomain *emif_clkdm, *mpuss_clkdm, *l3_1_clkdm, *l4wkup;
        struct clockdomain *ducati_clkdm, *l3_2_clkdm, *l4_per_clkdm;

+       if (!cpu_is_omap44xx())
+               return -ENODEV;
+
        if (omap_rev() == OMAP4430_REV_ES1_0) {
                WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
                return -ENODEV;
Regards
Ssantosh