diff options
Diffstat (limited to 'arch/mips/kernel/time.c')
| -rw-r--r-- | arch/mips/kernel/time.c | 66 |
1 files changed, 19 insertions, 47 deletions
diff --git a/arch/mips/kernel/time.c b/arch/mips/kernel/time.c index b45a7093ca2..8d0170969e2 100644 --- a/arch/mips/kernel/time.c +++ b/arch/mips/kernel/time.c @@ -5,8 +5,8 @@ * * Common time service routines for MIPS machines. * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */ @@ -21,11 +21,11 @@ #include <linux/timex.h> #include <linux/smp.h> #include <linux/spinlock.h> -#include <linux/module.h> +#include <linux/export.h> #include <asm/cpu-features.h> +#include <asm/cpu-type.h> #include <asm/div64.h> -#include <asm/smtc_ipi.h> #include <asm/time.h> /* @@ -38,7 +38,6 @@ int __weak rtc_mips_set_time(unsigned long sec) { return 0; } -EXPORT_SYMBOL(rtc_mips_set_time); int __weak rtc_mips_set_mmss(unsigned long nowtime) { @@ -50,13 +49,11 @@ int update_persistent_clock(struct timespec now) return rtc_mips_set_mmss(now.tv_sec); } -int null_perf_irq(void) +static int null_perf_irq(void) { return 0; } -EXPORT_SYMBOL(null_perf_irq); - int (*perf_irq)(void) = null_perf_irq; EXPORT_SYMBOL(perf_irq); @@ -65,8 +62,8 @@ EXPORT_SYMBOL(perf_irq); * time_init() - it does the following things. * * 1) plat_time_init() - - * a) (optional) set up RTC routines, - * b) (optional) calibrate and set the mips_hpt_frequency + * a) (optional) set up RTC routines, + * b) (optional) calibrate and set the mips_hpt_frequency * (only needed if you intended to use cpu counter as timer interrupt * source) * 2) calculate a couple of cached variables for later usage @@ -74,44 +71,11 @@ EXPORT_SYMBOL(perf_irq); unsigned int mips_hpt_frequency; -void __init clocksource_set_clock(struct clocksource *cs, unsigned int clock) -{ - u64 temp; - u32 shift; - - /* Find a shift value */ - for (shift = 32; shift > 0; shift--) { - temp = (u64) NSEC_PER_SEC << shift; - do_div(temp, clock); - if ((temp >> 32) == 0) - break; - } - cs->shift = shift; - cs->mult = (u32) temp; -} - -void __cpuinit clockevent_set_clock(struct clock_event_device *cd, - unsigned int clock) -{ - u64 temp; - u32 shift; - - /* Find a shift value */ - for (shift = 32; shift > 0; shift--) { - temp = (u64) clock << shift; - do_div(temp, NSEC_PER_SEC); - if ((temp >> 32) == 0) - break; - } - cd->shift = shift; - cd->mult = (u32) temp; -} - /* * This function exists in order to cause an error due to a duplicate * definition if platform code should have its own implementation. The hook * to use instead is plat_time_init. plat_time_init does not receive the - * irqaction pointer argument anymore. This is because any function which + * irqaction pointer argument anymore. This is because any function which * initializes an interrupt timer now takes care of its own request_irq rsp. * setup_irq calls and each clock_event_device should use its own * struct irqrequest. @@ -129,7 +93,7 @@ static __init int cpu_has_mfc0_count_bug(void) case CPU_R4000MC: /* * V3.0 is documented as suffering from the mfc0 from count bug. - * Afaik this is the last version of the R4000. Later versions + * Afaik this is the last version of the R4000. Later versions * were marketed as R4400. */ return 1; @@ -138,7 +102,7 @@ static __init int cpu_has_mfc0_count_bug(void) case CPU_R4400SC: case CPU_R4400MC: /* - * The published errata for the R4400 upto 3.0 say the CPU + * The published errata for the R4400 up to 3.0 say the CPU * has the mfc0 from count bug. */ if ((current_cpu_data.processor_id & 0xff) <= 0x30) @@ -157,6 +121,14 @@ void __init time_init(void) { plat_time_init(); - if (!mips_clockevent_init() || !cpu_has_mfc0_count_bug()) + /* + * The use of the R4k timer as a clock event takes precedence; + * if reading the Count register might interfere with the timer + * interrupt, then we don't use the timer as a clock source. + * We may still use the timer as a clock source though if the + * timer interrupt isn't reliable; the interference doesn't + * matter then, because we don't use the interrupt. + */ + if (mips_clockevent_init() != 0 || !cpu_has_mfc0_count_bug()) init_mips_clocksource(); } |