[PATCH v3 05/10] ARM: tegra: rework Tegra secondary CPU core bringup

Olof Johansson olof at lixom.net
Sun Feb 26 16:57:00 EST 2012


Hi,

On Mon, Feb 20, 2012 at 03:04:57PM -0800, Colin Cross wrote:
> On Thu, Feb 9, 2012 at 3:47 PM, Peter De Schrijver
> <pdeschrijver at nvidia.com> wrote:
> > Prepare the Tegra secondary CPU core bringup code for other Tegra variants.
> > The reset handler is also generalized to allow for future introduction of
> > powersaving modes which turn off the CPU cores.
> >
> > Based on work by:
> >
> > Scott Williams <scwilliams at nvidia.com>
> > Chris Johnson <cwj at nvidia.com>
> > Colin Cross <ccross at android.com>
> >
> > Signed-off-by: Peter De Schrijver <pdeschrijver at nvidia.com>
> > ---
> <snip>
> 
> > diff --git a/arch/arm/mach-tegra/headsmp.S b/arch/arm/mach-tegra/headsmp.S
> > index b5349b2..7973f1c 100644
> > --- a/arch/arm/mach-tegra/headsmp.S
> > +++ b/arch/arm/mach-tegra/headsmp.S
> 
> <snip>
> 
> > @@ -47,15 +64,116 @@ ENTRY(v7_invalidate_l1)
> >         mov     pc, lr
> >  ENDPROC(v7_invalidate_l1)
> >
> > +
> >  ENTRY(tegra_secondary_startup)
> > -       msr     cpsr_fsxc, #0xd3
> >         bl      v7_invalidate_l1
> > -       mrc     p15, 0, r0, c0, c0, 5
> > -        and    r0, r0, #15
> > -        ldr     r1, =0x6000f100
> > -        str     r0, [r1]
> > -1:      ldr     r2, [r1]
> > -        cmp     r0, r2
> > -        beq     1b
> > +       mov32   r0, 0xC5ACCE55
> > +       mcr     p14, 0, r0, c7, c12, 6
> 
> One minor nit, you should comment that this is enabling coresight.

Since it's trivial, I did it when I applied the patch here instead of having
Peter respin or add it separately.


-Olof



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