oprofile and ARM A9 hardware counter

[Will Deacon]

Santosh,

On Wed, Jan 18, 2012 at 12:33:23PM +0000, Shilimkar, Santosh wrote:
> On Wed, Jan 18, 2012 at 1:24 PM, Ming Lei <ming.lei at canonical.com> wrote:
> >>> diff --git a/arch/arm/mach-omap2/clockdomains44xx_data.c
> >>> b/arch/arm/mach-omap2/clockdomains44xx_data.c
> >>> index 9299ac2..41d2260 100644
> >>> --- a/arch/arm/mach-omap2/clockdomains44xx_data.c
> >>> +++ b/arch/arm/mach-omap2/clockdomains44xx_data.c
> >>> @@ -390,7 +390,7 @@ static struct clockdomain emu_sys_44xx_clkdm = {
> >>>        .prcm_partition   = OMAP4430_PRM_PARTITION,
> >>>        .cm_inst          = OMAP4430_PRM_EMU_CM_INST,
> >>>        .clkdm_offs       = OMAP4430_PRM_EMU_CM_EMU_CDOFFS,
> >>> -       .flags            = CLKDM_CAN_HWSUP,
> >>> +       .flags            = CLKDM_CAN_SWSUP,
> >>>  };
> >> NAK.
> >>
> >> You don't need this patch. What you saw on CAMERA was indeed
> >> a known bug but emulation domain has no such issues.
> >>
> >> So the accesses to emulation register should continue to work
> >> with the clock-domain being kept under hardware supervision.
> >
> > But why can this patch make omap4 pmu work?  Without the patch,
> > there are no CTI interrupts generated for pmu irq.
> >
> Interesting. For me debugger works which also relies on Emulation domain.
> 
> Need to see why CTI is behaving like this.

Did you ever get to the bottom of this? This change really is required in
order to generate PMU interrupts with the CTI and I don't know of any
alternative to the above.

Any suggestions?

Will