kexec: cpufreq: omap3: hangs in dpll3xxx.c::_omap3_dpll_write_clken()

kexec: cpufreq: omap3: hangs in dpll3xxx.c::_omap3_dpll_write_clken()

[Paolo Pisati]

I've been experiencing solid hangs on my beaglexm with v3.7 after
kexec:

here is my .config (omap2plus + EHCI/OHCI + CPUFREQ + DEVTMP):

http://people.canonical.com/~ppisati/omap3_cpufreq_kexec/config

here is the diff i added to get some debugging:

http://people.canonical.com/~ppisati/omap3_cpufreq_kexec/dpll-debug.diff

here is a trace of the kexeced kernel:

http://people.canonical.com/~ppisati/omap3_cpufreq_kexec/kexec-boot.txt

Since i'n not familiar with those dplls, can anyone shed some light?
-- 
bye,
p.

Re: kexec: cpufreq: omap3: hangs in dpll3xxx.c::_omap3_dpll_write_clken()

[Paul Walmsley]

On Tue, 11 Dec 2012, Paolo Pisati wrote:

> I've been experiencing solid hangs on my beaglexm with v3.7 after
> kexec:

Does it crash if you boot v3.7 directly from the bootloader, i.e., without 
kexec?


- Paul

Re: kexec: cpufreq: omap3: hangs in dpll3xxx.c::_omap3_dpll_write_clken()

[Paul Walmsley]

On Tue, 11 Dec 2012, Paul Walmsley wrote:

> On Tue, 11 Dec 2012, Paolo Pisati wrote:
> 
> > I've been experiencing solid hangs on my beaglexm with v3.7 after
> > kexec:
> 
> Does it crash if you boot v3.7 directly from the bootloader, i.e., without 
> kexec?

Also you might want to verify that the voltage on VDD1 is what the kernel 
thinks it is:

[    5.638183] notification 0 of frequency transition to 800000 kHz
[    5.644775] cpu cpu0: cpufreq-omap: 300 MHz, -1 mV --> 800 MHz, 1325 mV

You can probe this with a multimeter on one side of the VDD1 inductor.  
It's on the underside of the Beagle-XM near the DC input jack - it's 
marked "L4" on the silkscreen text.


- Paul

Re: kexec: cpufreq: omap3: hangs in dpll3xxx.c::_omap3_dpll_write_clken()

[Paolo Pisati]

On Tue, Dec 11, 2012 at 08:20:13PM +0000, Paul Walmsley wrote:
> On Tue, 11 Dec 2012, Paolo Pisati wrote:
> 
> > I've been experiencing solid hangs on my beaglexm with v3.7 after
> > kexec:
> 
> Does it crash if you boot v3.7 directly from the bootloader, i.e., without 
> kexec?

nope, works perfectly fine when booted from the bootlader.

-- 
bye,
p.

Re: kexec: cpufreq: omap3: hangs in dpll3xxx.c::_omap3_dpll_write_clken()

[Paolo Pisati]

On Tue, Dec 11, 2012 at 08:32:25PM +0000, Paul Walmsley wrote:
> On Tue, 11 Dec 2012, Paul Walmsley wrote:
> 
> > On Tue, 11 Dec 2012, Paolo Pisati wrote:
> > 
> > > I've been experiencing solid hangs on my beaglexm with v3.7 after
> > > kexec:
> > 
> > Does it crash if you boot v3.7 directly from the bootloader, i.e., without 
> > kexec?
> 
> Also you might want to verify that the voltage on VDD1 is what the kernel 
> thinks it is:
> 
> [    5.638183] notification 0 of frequency transition to 800000 kHz
> [    5.644775] cpu cpu0: cpufreq-omap: 300 MHz, -1 mV --> 800 MHz, 1325 mV
> 
> You can probe this with a multimeter on one side of the VDD1 inductor.  
> It's on the underside of the Beagle-XM near the DC input jack - it's 
> marked "L4" on the silkscreen text.

uhm no, my multimeter says it's around 113mV...

-- 
bye,
p.