Enable arm_global_timer for Zynq brakes boot

Sören Brinkmann soren.brinkmann at xilinx.com
Mon Aug 12 12:17:28 EDT 2013


On Mon, Aug 12, 2013 at 06:08:46PM +0200, Daniel Lezcano wrote:
> On 08/12/2013 06:03 PM, Sören Brinkmann wrote:
> > On Fri, Aug 09, 2013 at 10:27:57AM -0700, Stephen Boyd wrote:
> >> On 08/09, Daniel Lezcano wrote:
> >>>
> >>> yes, but at least the broadcast mechanism should send an IPI to cpu0 to
> >>> wake it up, no ? As Stephen stated this kind of configuration should has
> >>> never been tested before so the tick broadcast code is not handling this
> >>> case properly IMHO.
> >>>
> >>
> >> If you have a per-cpu tick device that isn't suffering from
> >> FEAT_C3_STOP why wouldn't you use that for the tick versus a
> >> per-cpu tick device that has FEAT_C3_STOP? It sounds like there
> >> is a bug in the preference logic or you should boost the rating
> >> of the arm global timer above the twd. Does this patch help? It
> >> should make the arm global timer the tick device and whatever the
> >> cadence timer you have into the broadcast device.
> > 
> > I finally got to test your patch. Unfortunately, it makes the system
> > hang even earlier:
> 
> [ ... ]
> 
> Can you boot with maxcpus=1 and then give the result of timer_list ?

That doesn't seem to help anymore. It hangs too. Same picture w/ and w/o
'maxcpus', except for
	[    0.000000] Kernel command line: console=ttyPS0,115200 earlyprintk maxcpus=1


	Sören





More information about the linux-arm-kernel mailing list