From mboxrd@z Thu Jan 1 00:00:00 1970 From: Magnus Damm Date: Thu, 22 Jan 2009 09:55:31 +0000 Subject: [PATCH 01/05] sh: rework clocksource and sched_clock Message-Id: <20090122095531.31653.60916.sendpatchset@rx1.opensource.se> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org From: Magnus Damm 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 --- arch/sh/include/asm/timer.h | 4 +- arch/sh/kernel/time_32.c | 59 +++++-------------------------------- arch/sh/kernel/timers/timer-tmu.c | 10 +++++- 3 files changed, 19 insertions(+), 54 deletions(-) --- 0001/arch/sh/include/asm/timer.h +++ work/arch/sh/include/asm/timer.h 2009-01-22 13:22:25.000000000 +0900 @@ -9,7 +9,6 @@ struct sys_timer_ops { int (*init)(void); int (*start)(void); int (*stop)(void); - cycle_t (*read)(void); #ifndef CONFIG_GENERIC_TIME unsigned long (*get_offset)(void); #endif @@ -39,6 +38,7 @@ struct sys_timer *get_sys_timer(void); /* arch/sh/kernel/time.c */ void handle_timer_tick(void); -extern unsigned long sh_hpt_frequency; + +extern struct clocksource clocksource_sh; #endif /* __ASM_SH_TIMER_H */ --- 0001/arch/sh/kernel/time_32.c +++ work/arch/sh/kernel/time_32.c 2009-01-22 13:23:11.000000000 +0900 @@ -41,14 +41,6 @@ static int null_rtc_set_time(const time_ 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); - } --- 0001/arch/sh/kernel/timers/timer-tmu.c +++ work/arch/sh/kernel/timers/timer-tmu.c 2009-01-22 13:22:12.000000000 +0900 @@ -254,7 +254,14 @@ static int tmu_timer_init(void) _tmu_start(TMU1); - sh_hpt_frequency = clk_get_rate(&tmu1_clk); + clocksource_sh.rating = 200; + clocksource_sh.mask = CLOCKSOURCE_MASK(32); + clocksource_sh.read = tmu_timer_read; + clocksource_sh.shift = 10; + clocksource_sh.mult = clocksource_hz2mult(clk_get_rate(&tmu1_clk), + clocksource_sh.shift); + clocksource_sh.flags = CLOCK_SOURCE_IS_CONTINUOUS; + clocksource_register(&clocksource_sh); tmu0_clockevent.mult = div_sc(frequency, NSEC_PER_SEC, tmu0_clockevent.shift); @@ -274,7 +281,6 @@ static struct sys_timer_ops tmu_timer_op .init = tmu_timer_init, .start = tmu_timer_start, .stop = tmu_timer_stop, - .read = tmu_timer_read, }; struct sys_timer tmu_timer = {