Re: dw_apb_timer_of.c: remove parts that were picoxcell-specific

Pavel Machek
2013-05-06T12:48:18Z

Hi!

Ping? Previous version was tested by Dinh, and this one is based on
Jamie's updates, so I assume it is acceptable for him, too.

It brings two platforms closer together, and makes time actually work
on socfpga. It would be good to get it applied.

Thanks,
Pavel

On Fri 2013-04-26 23:43:13, Pavel Machek wrote:
> It seems we made a mistake when creating dw_apb_timer_of.c:
> picoxcell sched_clock had parts that were not related to
> dw_apb_timer, yet we moved them to dw_apb_timer_of, and tried to
> use them on socfpga.
>
> This results in system where user/system time is not measured
> properly, as demonstrated by
>
> time dd if=/dev/urandom of=/dev/zero bs=100000 count=100
>
> So this patch switches sched_clock to hardware that exists on both
> platforms, and adds missing of_node_put() in dw_apb_timer_init().
>
> Signed-off-by: Pavel Machek <pavel@denx.de>
>
> diff --git a/arch/arm/mach-picoxcell/common.h b/arch/arm/mach-picoxcell/common.h
> index 481b42a..237fb3b 100644
> --- a/arch/arm/mach-picoxcell/common.h
> +++ b/arch/arm/mach-picoxcell/common.h
> @@ -12,6 +12,4 @@
>
> #include <asm/mach/time.h>
>
> -extern void dw_apb_timer_init(void);
> -
> #endif /* __PICOXCELL_COMMON_H__ */
> diff --git a/drivers/clocksource/dw_apb_timer.c b/drivers/clocksource/dw_apb_timer.c
> index 8c2a35f..460ac99 100644
> --- a/drivers/clocksource/dw_apb_timer.c
> +++ b/drivers/clocksource/dw_apb_timer.c
> @@ -21,12 +21,6 @@
> #define APBT_MIN_PERIOD 4
> #define APBT_MIN_DELTA_USEC 200
>
> -#define APBTMR_N_LOAD_COUNT 0x00
> -#define APBTMR_N_CURRENT_VALUE 0x04
> -#define APBTMR_N_CONTROL 0x08
> -#define APBTMR_N_EOI 0x0c
> -#define APBTMR_N_INT_STATUS 0x10
> -
> #define APBTMRS_INT_STATUS 0xa0
> #define APBTMRS_EOI 0xa4
> #define APBTMRS_RAW_INT_STATUS 0xa8
> diff --git a/drivers/clocksource/dw_apb_timer_of.c b/drivers/clocksource/dw_apb_timer_of.c
> index ab09ed3..0fa3104 100644
> --- a/drivers/clocksource/dw_apb_timer_of.c
> +++ b/drivers/clocksource/dw_apb_timer_of.c
> @@ -57,6 +57,15 @@ static void add_clockevent(struct device_node *event_timer)
> dw_apb_clockevent_register(ced);
> }
>
> +static void __iomem *sched_io_base;
> +
> +/* This is actually same as __apbt_read_clocksource(), but with
> + different interface */
> +static u32 read_sched_clock_sptimer(void)
> +{
> + return ~__raw_readl(sched_io_base + APBTMR_N_CURRENT_VALUE);
> +}
> +
> static void add_clocksource(struct device_node *source_timer)
> {
> void __iomem *iobase;
> @@ -71,41 +80,27 @@ static void add_clocksource(struct device_node *source_timer)
>
> dw_apb_clocksource_start(cs);
> dw_apb_clocksource_register(cs);
> -}
>
> -static void __iomem *sched_io_base;
> -
> -static u32 read_sched_clock(void)
> -{
> - return __raw_readl(sched_io_base);
> + sched_io_base = iobase;
> + setup_sched_clock(read_sched_clock_sptimer, 32, rate);
> }
>
> -static const struct of_device_id sptimer_ids[] __initconst = {
> - { .compatible = "picochip,pc3x2-rtc" },
> +static const struct of_device_id osctimer_ids[] __initconst = {
> + { .compatible = "picochip,pc3x2-timer" },
> + { .compatible = "snps,dw-apb-timer-osc" },
> { .compatible = "snps,dw-apb-timer-sp" },
> - { /* Sentinel */ },
> + { /* Sentinel */ },
> };
>
> -static void init_sched_clock(void)
> -{
> - struct device_node *sched_timer;
> - u32 rate;
> -
> - sched_timer = of_find_matching_node(NULL, sptimer_ids);
> - if (!sched_timer)
> - panic("No RTC for sched clock to use");
> +/*
> + You don't have to use dw_apb_timer for scheduler clock,
> + this should also work fine on arm:
>
> - timer_get_base_and_rate(sched_timer, &sched_io_base, &rate);
> - of_node_put(sched_timer);
> + twd_local_timer_of_register();
> + arch_timer_of_register();
> + arch_timer_sched_clock_init();
> +*/
>
> - setup_sched_clock(read_sched_clock, 32, rate);
> -}
> -
> -static const struct of_device_id osctimer_ids[] __initconst = {
> - { .compatible = "picochip,pc3x2-timer" },
> - { .compatible = "snps,dw-apb-timer-osc" },
> - {},
> -};
>
> void __init dw_apb_timer_init(void)
> {
> @@ -121,7 +116,6 @@ void __init dw_apb_timer_init(void)
> panic("No timer for clocksource");
> add_clocksource(source_timer);
>
> + of_node_put(event_timer);
> of_node_put(source_timer);
> -
> - init_sched_clock();
> }
> diff --git a/include/linux/dw_apb_timer.h b/include/linux/dw_apb_timer.h
> index dd755ce..a64c987 100644
> --- a/include/linux/dw_apb_timer.h
> +++ b/include/linux/dw_apb_timer.h
> @@ -17,6 +17,12 @@
> #include <linux/clocksource.h>
> #include <linux/interrupt.h>
>
> +#define APBTMR_N_LOAD_COUNT 0x00
> +#define APBTMR_N_CURRENT_VALUE 0x04
> +#define APBTMR_N_CONTROL 0x08
> +#define APBTMR_N_EOI 0x0c
> +#define APBTMR_N_INT_STATUS 0x10
> +
> #define APBTMRS_REG_SIZE 0x14
>
> struct dw_apb_timer {