[RFC PATCH 07/16] ARM: local timers: move OMAP4 to LOCAL_TIMER_DEVICES/ARM_SMP_TWD

[Santosh Shilimkar]

On 6/17/2011 12:36 AM, Marc Zyngier wrote:
> Convert the OMAP4 platforms to use the new arm_smp_twd driver.
> Add the platform device and register it as early platform device.
>
> Tested on a Pandaboard.
>
> Cc: Tony Lindgren<tony at atomide.com>
> Cc: Santosh Shilimkar<santosh.shilimkar at ti.com>
> Signed-off-by: Marc Zyngier<marc.zyngier at arm.com>
> ---
>   arch/arm/mach-omap2/Kconfig     |    3 +-
>   arch/arm/mach-omap2/Makefile    |    1 -
>   arch/arm/mach-omap2/timer-gp.c  |   40 ++++++++++++++++++++++++++++++++------
>   arch/arm/mach-omap2/timer-mpu.c |   40 ---------------------------------------
>   4 files changed, 35 insertions(+), 49 deletions(-)
>   delete mode 100644 arch/arm/mach-omap2/timer-mpu.c
>
> diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
> index 19d5891..805d7b9 100644
> --- a/arch/arm/mach-omap2/Kconfig
> +++ b/arch/arm/mach-omap2/Kconfig
> @@ -44,7 +44,8 @@ config ARCH_OMAP4
>   	depends on ARCH_OMAP2PLUS
>   	select CPU_V7
>   	select ARM_GIC
> -	select LOCAL_TIMERS if SMP
> +	select LOCAL_TIMER_DEVICES if SMP
> +	select ARM_SMP_TWD
>   	select PL310_ERRATA_588369
>   	select PL310_ERRATA_727915
>   	select ARM_ERRATA_720789
> diff --git a/arch/arm/mach-omap2/Makefile b/arch/arm/mach-omap2/Makefile
> index b148077..f48c989 100644
> --- a/arch/arm/mach-omap2/Makefile
> +++ b/arch/arm/mach-omap2/Makefile
> @@ -22,7 +22,6 @@ obj-$(CONFIG_TWL4030_CORE) += omap_twl.o
>
>   # SMP support ONLY available for OMAP4
>   obj-$(CONFIG_SMP)			+= omap-smp.o omap-headsmp.o
> -obj-$(CONFIG_LOCAL_TIMERS)		+= timer-mpu.o
>   obj-$(CONFIG_HOTPLUG_CPU)		+= omap-hotplug.o
>   obj-$(CONFIG_ARCH_OMAP4)		+= omap44xx-smc.o omap4-common.o
>
> diff --git a/arch/arm/mach-omap2/timer-gp.c b/arch/arm/mach-omap2/timer-gp.c
> index 3b9cf85..f2f0db6 100644
> --- a/arch/arm/mach-omap2/timer-gp.c
> +++ b/arch/arm/mach-omap2/timer-gp.c
> @@ -35,10 +35,10 @@
>   #include<linux/irq.h>
>   #include<linux/clocksource.h>
>   #include<linux/clockchips.h>
> +#include<linux/platform_device.h>
>
>   #include<asm/mach/time.h>
>   #include<plat/dmtimer.h>
> -#include<asm/localtimer.h>
>   #include<asm/sched_clock.h>
>   #include<plat/common.h>
>   #include<plat/omap_hwmod.h>
> @@ -247,18 +247,44 @@ static void __init omap2_gp_clocksource_init(void)
>   }
>   #endif
>
> +#ifdef CONFIG_ARM_SMP_TWD
> +static struct resource omap2_gp_twd_resources[] = {
> +	{
> +		.start	= OMAP44XX_LOCAL_TWD_BASE,
> +		.end	= OMAP44XX_LOCAL_TWD_BASE + 0x10,
> +		.flags	= IORESOURCE_MEM,
> +	},
> +	{
> +		.start	= OMAP44XX_IRQ_LOCALTIMER,
> +		.end	= OMAP44XX_IRQ_LOCALTIMER,
> +		.flags	= IORESOURCE_IRQ,
> +	},
> +};
> +
> +static struct platform_device omap2_gp_twd_device = {
> +	.name		= "arm_smp_twd",
> +	.id		= -1,
Why is the id set to -1 ?

> +	.resource	= omap2_gp_twd_resources,
> +	.num_resources	= ARRAY_SIZE(omap2_gp_twd_resources),
> +};
> +
> +static struct platform_device *omap2_gp_early_devices[] = {
> +	&omap2_gp_twd_device,
> +};
> +#endif
> +
>   static void __init omap2_gp_timer_init(void)
>   {
> -#ifdef CONFIG_LOCAL_TIMERS
> -	if (cpu_is_omap44xx()) {
> -		twd_base = ioremap(OMAP44XX_LOCAL_TWD_BASE, SZ_256);
> -		BUG_ON(!twd_base);
> -	}
> -#endif
>   	omap_dm_timer_init();
>
>   	omap2_gp_clockevent_init();
>   	omap2_gp_clocksource_init();
> +#ifdef CONFIG_ARM_SMP_TWD
> +	/* Local timers are not supprted on OMAP4430 ES1.0 */
> +	if (omap_rev() != OMAP4430_REV_ES1_0)
> +		early_platform_add_devices(omap2_gp_early_devices,
> +					   ARRAY_SIZE(omap2_gp_early_devices));
> +#endif
>   }
>
These changes looks good.

>   struct sys_timer omap_timer = {
> diff --git a/arch/arm/mach-omap2/timer-mpu.c b/arch/arm/mach-omap2/timer-mpu.c
> deleted file mode 100644
> index 1fd5ca5..0000000
> --- a/arch/arm/mach-omap2/timer-mpu.c
> +++ /dev/null
> @@ -1,40 +0,0 @@
> -/*
> - * The MPU local timer source file. In OMAP4, both cortex-a9 cores have
> - * own timer in it's MPU domain. These timers will be driving the
> - * linux kernel SMP tick framework when active. These timers are not
> - * part of the wake up domain.
> - *
> - * Copyright (C) 2009 Texas Instruments, Inc.
> - *
> - * Author:
> - *      Santosh Shilimkar<santosh.shilimkar at ti.com>
> - *
> - * This file is based on arm realview smp platform file.
> - * Copyright (C) 2002 ARM Ltd.
> - *
> - * This program is free software; you can redistribute it and/or modify
> - * it under the terms of the GNU General Public License version 2 as
> - * published by the Free Software Foundation.
> - */
> -#include<linux/init.h>
> -#include<linux/smp.h>
> -#include<linux/clockchips.h>
> -#include<asm/irq.h>
> -#include<asm/smp_twd.h>
> -#include<asm/localtimer.h>
> -#include<asm/hardware/gic.h>
> -
> -/*
> - * Setup the local clock events for a CPU.
> - */
> -int __cpuinit local_timer_setup(struct clock_event_device *evt)
> -{
> -	/* Local timers are not supprted on OMAP4430 ES1.0 */
> -	if (omap_rev() == OMAP4430_REV_ES1_0)
> -		return -ENXIO;
> -
> -	evt->irq = gic_ppi_to_vppi(OMAP44XX_IRQ_LOCALTIMER);
> -	twd_timer_setup(evt);
> -	return 0;
> -}
> -
And this one is even better. -40 lines from arch/arm/*omap*/

I am fine with all changes except the id value. With that
clarified,
Reviewedd-by: Santosh Shilimkar <santosh.shilimkar at ti.com>

Regards
Santosh