From 955c0778723501cc16fec40501cd54b7e72d3e74 Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Thu, 22 Jan 2009 09:55:31 +0000 Subject: sh: rework clocksource and sched_clock Rework and simplify the sched_clock and clocksource code. Instead of registering the clocksource in a shared file we move it into the tmu driver. Also, add code to handle sched_clock in the case of no clocksource. Signed-off-by: Magnus Damm Signed-off-by: Paul Mundt --- arch/sh/kernel/time_32.c | 59 ++++++++---------------------------------------- 1 file changed, 9 insertions(+), 50 deletions(-) (limited to 'arch/sh/kernel/time_32.c') diff --git a/arch/sh/kernel/time_32.c b/arch/sh/kernel/time_32.c index 8457f83242c5..ca22eef669ae 100644 --- a/arch/sh/kernel/time_32.c +++ b/arch/sh/kernel/time_32.c @@ -41,14 +41,6 @@ static int null_rtc_set_time(const time_t secs) return 0; } -/* - * Null high precision timer functions for systems lacking one. - */ -static cycle_t null_hpt_read(void) -{ - return 0; -} - void (*rtc_sh_get_time)(struct timespec *) = null_rtc_get_time; int (*rtc_sh_set_time)(const time_t) = null_rtc_set_time; @@ -200,42 +192,21 @@ device_initcall(timer_init_sysfs); void (*board_time_init)(void); -/* - * Shamelessly based on the MIPS and Sparc64 work. - */ -static unsigned long timer_ticks_per_nsec_quotient __read_mostly; -unsigned long sh_hpt_frequency = 0; - -#define NSEC_PER_CYC_SHIFT 10 - -static struct clocksource clocksource_sh = { +struct clocksource clocksource_sh = { .name = "SuperH", - .rating = 200, - .mask = CLOCKSOURCE_MASK(32), - .read = null_hpt_read, - .shift = 16, - .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; -static void __init init_sh_clocksource(void) -{ - if (!sh_hpt_frequency || clocksource_sh.read == null_hpt_read) - return; - - clocksource_sh.mult = clocksource_hz2mult(sh_hpt_frequency, - clocksource_sh.shift); - - timer_ticks_per_nsec_quotient = - clocksource_hz2mult(sh_hpt_frequency, NSEC_PER_CYC_SHIFT); - - clocksource_register(&clocksource_sh); -} - #ifdef CONFIG_GENERIC_TIME unsigned long long sched_clock(void) { - unsigned long long ticks = clocksource_sh.read(); - return (ticks * timer_ticks_per_nsec_quotient) >> NSEC_PER_CYC_SHIFT; + unsigned long long cycles; + + /* jiffies based sched_clock if no clocksource is installed */ + if (!clocksource_sh.rating) + return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ); + + cycles = clocksource_sh.read(); + return cyc2ns(&clocksource_sh, cycles); } #endif @@ -260,16 +231,4 @@ void __init time_init(void) */ sys_timer = get_sys_timer(); printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); - - - if (sys_timer->ops->read) - clocksource_sh.read = sys_timer->ops->read; - - init_sh_clocksource(); - - if (sh_hpt_frequency) - printk("Using %lu.%03lu MHz high precision timer.\n", - ((sh_hpt_frequency + 500) / 1000) / 1000, - ((sh_hpt_frequency + 500) / 1000) % 1000); - } -- cgit v1.2.2 From 07821d3310996746a2cf1e9c705ffe64223d1112 Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Thu, 22 Jan 2009 09:55:49 +0000 Subject: sh: fix no sys_timer case Handle the case with a sys_timer set to NULL. Signed-off-by: Magnus Damm Signed-off-by: Paul Mundt --- arch/sh/kernel/time_32.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'arch/sh/kernel/time_32.c') diff --git a/arch/sh/kernel/time_32.c b/arch/sh/kernel/time_32.c index ca22eef669ae..766554ba2a5b 100644 --- a/arch/sh/kernel/time_32.c +++ b/arch/sh/kernel/time_32.c @@ -181,7 +181,12 @@ static struct sysdev_class timer_sysclass = { static int __init timer_init_sysfs(void) { - int ret = sysdev_class_register(&timer_sysclass); + int ret; + + if (!sys_timer) + return 0; + + ret = sysdev_class_register(&timer_sysclass); if (ret != 0) return ret; @@ -230,5 +235,8 @@ void __init time_init(void) * initialized for us. */ sys_timer = get_sys_timer(); + if (unlikely(!sys_timer)) + panic("System timer missing.\n"); + printk(KERN_INFO "Using %s for system timer\n", sys_timer->name); } -- cgit v1.2.2 From c161e40f45d32b48f8facbee17720e708607002f Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Thu, 29 Jan 2009 18:11:25 +0900 Subject: sh: Don't enable GENERIC_TIME for the CMT clockevent driver yet. GENERIC_TIME still depends on the clocksource bits being there, which is presently not supported. This allows the CMT clockevent driver to be used alongside alternate system timers that do not yet provide a clocksource of their own (MTU2 and so on in the case of SH-2A). Signed-off-by: Paul Mundt --- arch/sh/kernel/time_32.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'arch/sh/kernel/time_32.c') diff --git a/arch/sh/kernel/time_32.c b/arch/sh/kernel/time_32.c index 766554ba2a5b..c34e1e0f9b02 100644 --- a/arch/sh/kernel/time_32.c +++ b/arch/sh/kernel/time_32.c @@ -104,7 +104,6 @@ int do_settimeofday(struct timespec *tv) EXPORT_SYMBOL(do_settimeofday); #endif /* !CONFIG_GENERIC_TIME */ -#ifndef CONFIG_GENERIC_CLOCKEVENTS /* last time the RTC clock got updated */ static long last_rtc_update; @@ -148,7 +147,6 @@ void handle_timer_tick(void) update_process_times(user_mode(get_irq_regs())); #endif } -#endif /* !CONFIG_GENERIC_CLOCKEVENTS */ #ifdef CONFIG_PM int timer_suspend(struct sys_device *dev, pm_message_t state) -- cgit v1.2.2