[PATCH 2/2] ARM: mxc: Add sched_clock to mxc platform

[u.kleine-koenig@pengutronix.de (Uwe Kleine-König)]

On Thu, Mar 17, 2011 at 01:44:30PM +0100, Jan Weitzel wrote:
> Add sched_clock using cyc_to_sched_clock and update_sched_clock
> with HAVE_SCHED_CLOCK
> tested on iMX27 and iMX35
> 
> Signed-off-by: Jan Weitzel <j.weitzel@phytec.de>
> ---
>  arch/arm/Kconfig         |    1 +
>  arch/arm/plat-mxc/time.c |   16 ++++++++++++++++
>  2 files changed, 17 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index 26d45e5..076e307 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -356,6 +356,7 @@ config ARCH_MXC
>  	select GENERIC_CLOCKEVENTS
>  	select ARCH_REQUIRE_GPIOLIB
>  	select CLKDEV_LOOKUP
> +	select HAVE_SCHED_CLOCK
>  	help
>  	  Support for Freescale MXC/iMX-based family of processors
>  
> diff --git a/arch/arm/plat-mxc/time.c b/arch/arm/plat-mxc/time.c
> index 0142e4b..2237ff8 100644
> --- a/arch/arm/plat-mxc/time.c
> +++ b/arch/arm/plat-mxc/time.c
> @@ -27,6 +27,7 @@
>  #include <linux/clk.h>
>  
>  #include <mach/hardware.h>
> +#include <asm/sched_clock.h>
>  #include <asm/mach/time.h>
>  #include <mach/common.h>
>  
> @@ -128,6 +129,20 @@ static struct clocksource clocksource_mxc = {
>  	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
>  };
>  
> +static DEFINE_CLOCK_DATA(cd);
> +unsigned long long notrace sched_clock(void)
> +{
> +	cycle_t cyc = clocksource_mxc.read(&clocksource_mxc);
> +
> +	return cyc_to_sched_clock(&cd, cyc, (u32)~0);
This cast to u32 isn't needed. The third argument to cyc_to_sched_clock
(and update_sched_clock below) is a u32 anyhow. I would support 

	~(u32)0

though.

Best regards
Uwe

> +}
> +
> +static void notrace mxc_update_sched_clock(void)
> +{
> +	cycle_t cyc = clocksource_mxc.read(&clocksource_mxc);
> +	update_sched_clock(&cd, cyc, (u32)~0);
> +}
> +
>  static int __init mxc_clocksource_init(struct clk *timer_clk)
>  {
>  	unsigned int c = clk_get_rate(timer_clk);
> @@ -137,6 +152,7 @@ static int __init mxc_clocksource_init(struct clk *timer_clk)
>  	else
>  		clocksource_mxc.read = mx1_2_get_cycles;
>  
> +	init_sched_clock(&cd, mxc_update_sched_clock, 32, c);
>  	clocksource_register_hz(&clocksource_mxc, c);
>  
>  	return 0;

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |