[PATCH] ARM/sp810: introduce API to change system mode
Linus Walleij
linus.walleij at linaro.org
Mon Feb 27 10:29:58 EST 2012
On Mon, Feb 27, 2012 at 11:55 AM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Mon, Feb 27, 2012 at 11:38:14AM +0100, Linus Walleij wrote:
>> Maybe I'm delusional but I think this could help centralizing the use
>> of the SP* cells, since they're obviously used in both SPEAr and
>> versatile express.
>
> They can be used in any PrimeXsys based system, and I don't see that
> there's anything which guarantees having both a SP810 and SP804
> together.
>
> There are platforms which have SP804 without SP810 - Integrator CP
> and bcmring seem to fall into that category.
I was more thinking the other way around - I think that all systems
with an SP810 also have an SP804.
I'm led to thinking this because of these registers:
#define SCCTRL_TIMEREN0SEL_REFCLK (0 << 15)
#define SCCTRL_TIMEREN0SEL_TIMCLK (1 << 15)
#define SCCTRL_TIMEREN1SEL_REFCLK (0 << 17)
#define SCCTRL_TIMEREN1SEL_TIMCLK (1 << 17)
TIMER0 and TIMER1 seems to indicate TIMER0 and TIMER1
of the SP804 block.
In any case it seems to depend on CONFIG_ARM_TIMER_SP804.
> But... the register concerned does a whole load of other things, and
> I'm not sure we want to have accesses to it de-centralized.
Sure, just arch/arm/common/sc-810.c works fine as well.
Now I got incentive to finally write that letter to Greg about what
to do with system controllers.
Yours,
Linus Walleij
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