Use MMIO clocksource for 32kHz counter

Commit Message

Tony Lindgren June 27, 2011, 7:11 p.m. UTC

* Tony Lindgren <[e-mail]> [110627 05:33]:
> * Russell King - ARM Linux <[e-mail]> [110627 05:28]:
> > --- a/arch/arm/plat-omap/counter_32k.c
> > +++ b/arch/arm/plat-omap/counter_32k.c
> > +#ifdef CONFIG_ARCH_OMAP16XX
> > +		else if (cpu_is_omap16xx())
> > +			base = OMAP2_L4_IO_ADDRESS(OMAP16XX_TIMER_32K_SYNCHRONIZED);

BTW, the above should have been OMAP1_IO_ADDRESS instead..
  
> You should be able to replace the above with just ioremap as we now
> have the static mappings.

..here's a patch to use ioremap with comment added about the static
mapping requirements.

Thanks for getting rid of hopefully the last remaining omap_readl
for omap2+ BTW :)

Tony

Comments

Russell King - ARM Linux July 10, 2011, 2:15 p.m. UTC | #1

On Mon, Jun 27, 2011 at 12:11:02PM -0700, Tony Lindgren wrote:
> * Tony Lindgren <[e-mail]> [110627 05:33]:
> > * Russell King - ARM Linux <[e-mail]> [110627 05:28]:
> > > --- a/arch/arm/plat-omap/counter_32k.c
> > > +++ b/arch/arm/plat-omap/counter_32k.c
> > > +#ifdef CONFIG_ARCH_OMAP16XX
> > > +		else if (cpu_is_omap16xx())
> > > +			base = OMAP2_L4_IO_ADDRESS(OMAP16XX_TIMER_32K_SYNCHRONIZED);
> 
> BTW, the above should have been OMAP1_IO_ADDRESS instead..
>   
> > You should be able to replace the above with just ioremap as we now
> > have the static mappings.
> 
> ..here's a patch to use ioremap with comment added about the static
> mapping requirements.
> 
> Thanks for getting rid of hopefully the last remaining omap_readl
> for omap2+ BTW :)

What're we doing with this patch and your follow-up patch?

Patch

--- a/arch/arm/plat-omap/counter_32k.c
+++ b/arch/arm/plat-omap/counter_32k.c
@@ -106,34 +106,30 @@  int __init omap_init_clocksource_32k(void)
 			"%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 (0)
-			base = NULL;
-#ifdef CONFIG_ARCH_OMAP16XX
-		else if (cpu_is_omap16xx())
-			base = OMAP2_L4_IO_ADDRESS(OMAP16XX_TIMER_32K_SYNCHRONIZED);
-#endif
-#ifdef CONFIG_SOC_OMAP2420
-		else if (cpu_is_omap2420())
-			base = OMAP2_L4_IO_ADDRESS(OMAP2420_32KSYNCT_BASE + 0x10);
-#endif
-#ifdef CONFIG_SOC_OMAP2430
+		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())
-			base = OMAP2_L4_IO_ADDRESS(OMAP2430_32KSYNCT_BASE + 0x10);
-#endif
-#ifdef CONFIG_ARCH_OMAP3
+			pbase = OMAP2430_32KSYNCT_BASE + 0x10;
 		else if (cpu_is_omap34xx())
-			base = OMAP2_L4_IO_ADDRESS(OMAP3430_32KSYNCT_BASE + 0x10);
-#endif
-#ifdef CONFIG_ARCH_OMAP4
+			pbase = OMAP3430_32KSYNCT_BASE + 0x10;
 		else if (cpu_is_omap44xx())
-			base = OMAP2_L4_IO_ADDRESS(OMAP4430_32KSYNCT_BASE + 0x10);
-#endif
+			pbase = OMAP4430_32KSYNCT_BASE + 0x10;
 		else
 			return -ENODEV;
 
+		/* For this to work we must have a static mapping in io.c for this area */
+		base = ioremap(pbase, size);
+		if (!base)
+			return -ENODEV;
+
 		sync_32k_ick = clk_get(NULL, "omap_32ksync_ick");
 		if (!IS_ERR(sync_32k_ick))
 			clk_enable(sync_32k_ick);