[PATCH 2/3] mach-ux500: initialize l2x0 at arch_init time

Sascha Hauer s.hauer at pengutronix.de
Wed Aug 24 08:14:26 EDT 2011


Hi Linus,

On Wed, Aug 24, 2011 at 01:59:40PM +0200, Linus Walleij wrote:
> On Wed, Aug 24, 2011 at 12:12 PM, Kyungmin Park <kmpark at infradead.org> wrote:
> > On Wed, Aug 24, 2011 at 6:56 PM, Santosh <santosh.shilimkar at ti.com> wrote:
> >> On Wednesday 24 August 2011 02:53 PM, Linus Walleij wrote:
> >>
> >> More and more you delay L2 cache enable in boot-process,
> >> your boot-up time is going to shoot-up.
> >>
> >> Have you thought about it. Cache's should be enabled as
> >> early as possible.
> >
> > Right, after change from early_init to arch_init. it takes more time.
> 
> Hm no good. I'll drop this.
> 
> We've seen that if we try to unlock the I&D l2x0 at the
> early_initcall() as in [3/3] it will sometimes fail, like it's
> still locked down afterwards. Calling it from .init_machine()
> appears to work. So in my dumbness I moved it to
> arch_initcall() which should be equivalent. Does anyone
> have some subtle hint or experience on how to get around
> that one issue, or should I just put in a second
> arch_initcall() for just the unlocking?
> 
> Sascha, I guess Freescale should also move the l2x0 init to
> early_init() in mach-imx/cache-l2x0.c if possible. Can
> you try the below on your machine(s)?

Sure, what are you interested in? If it works reliably or if works
faster?

Sascha

> 
> diff --git a/arch/arm/mach-imx/cache-l2x0.c b/arch/arm/mach-imx/cache-l2x0.c
> index 69d1322..e5538a4 100644
> --- a/arch/arm/mach-imx/cache-l2x0.c
> +++ b/arch/arm/mach-imx/cache-l2x0.c
> @@ -53,4 +53,4 @@ static int mxc_init_l2x0(void)
> 
>         return 0;
>  }
> -arch_initcall(mxc_init_l2x0);
> +early_initcall(mxc_init_l2x0);
> 
> Yours,
> Linus Walleij
> 

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