[PATCH 1/3] ARM: OMAP2+: 32k-counter: Use hwmod lookup to check presence of 32k timer
Hiremath, Vaibhav
hvaibhav at ti.com
Wed Mar 7 04:48:06 EST 2012
On Tue, Mar 06, 2012 at 04:25:30, Tony Lindgren wrote:
> Hi,
>
> * Vaibhav Hiremath <hvaibhav at ti.com> [120119 06:01]:
> > OMAP device has 32k-sync timer which is currently used as a
> > clocksource in the kernel (omap2plus_defconfig).
> > The current implementation uses compile time selection between
> > gp-timer and 32k-sync timer, which breaks multi-omap build for
> > the devices like AM33xx, where 32k-sync timer is not available.
> >
> > So use hwmod database lookup mechanism, through which at run-time
> > we can identify availability of 32k-sync timer on the device,
> > else fall back to gp-timer.
> ...
>
> > --- a/arch/arm/plat-omap/counter_32k.c
> > +++ b/arch/arm/plat-omap/counter_32k.c
> > @@ -69,52 +69,55 @@ void read_persistent_clock(struct timespec *ts)
> >
> > int __init omap_init_clocksource_32k(void)
> > {
> > - static char err[] __initdata = KERN_ERR
> > - "%s: can't register clocksource!\n";
> > -
> > - if (cpu_is_omap16xx() || cpu_class_is_omap2()) {
> > - u32 pbase;
> > - unsigned long size = SZ_4K;
> > - void __iomem *base;
> > - struct clk *sync_32k_ick;
> > -
> > - if (cpu_is_omap16xx()) {
> > - pbase = OMAP16XX_TIMER_32K_SYNCHRONIZED;
> > - size = SZ_1K;
> > - } else if (cpu_is_omap2420())
> > - pbase = OMAP2420_32KSYNCT_BASE + 0x10;
> > - else if (cpu_is_omap2430())
> > - pbase = OMAP2430_32KSYNCT_BASE + 0x10;
> > - else if (cpu_is_omap34xx())
> > - pbase = OMAP3430_32KSYNCT_BASE + 0x10;
> > - else if (cpu_is_omap44xx())
> > - pbase = OMAP4430_32KSYNCT_BASE + 0x10;
> > - else
> > + u32 pbase;
> > + unsigned long size = SZ_4K;
> > + void __iomem *base;
> > + struct clk *sync_32k_ick;
> > +
> > + if (cpu_is_omap16xx()) {
> > + pbase = OMAP16XX_TIMER_32K_SYNCHRONIZED;
> > + size = SZ_1K;
> > + } else if (cpu_class_is_omap2()) {
> > + struct omap_hwmod *oh;
> > + const char *oh_name = "counter_32k";
> > +
> > + oh = omap_hwmod_lookup(oh_name);
> > + if (!oh || oh->slaves_cnt == 0) {
> > + pr_err("Could not lookup %s hwmod\n", oh_name);
> > return -ENODEV;
> > + }
> > + pbase = oh->slaves[0]->addr->pa_start + 0x10;
> > + } else {
> > + return -ENODEV;
> > + }
>
> How about have separate omap1 and omap2+ init functions that
> call a common function and passes the pbase as a parameter?
>
> That way we can get rid of the cpu_is_omapxxxx tests here.
>
Ok, let me clean this code accordingly and submit the next version.
Thanks,
Vaibhav
> Regards,
>
> Tony
>
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