diff options
Diffstat (limited to 'arch/mips/mti-malta/malta-time.c')
| -rw-r--r-- | arch/mips/mti-malta/malta-time.c | 83 |
1 files changed, 50 insertions, 33 deletions
diff --git a/arch/mips/mti-malta/malta-time.c b/arch/mips/mti-malta/malta-time.c index 8607b0dd29f6..a144b89cf9ba 100644 --- a/arch/mips/mti-malta/malta-time.c +++ b/arch/mips/mti-malta/malta-time.c @@ -17,7 +17,6 @@ * * Setting up the clock on the MIPS boards. */ - #include <linux/types.h> #include <linux/i8253.h> #include <linux/init.h> @@ -25,7 +24,6 @@ #include <linux/sched.h> #include <linux/spinlock.h> #include <linux/interrupt.h> -#include <linux/time.h> #include <linux/timex.h> #include <linux/mc146818rtc.h> @@ -34,11 +32,11 @@ #include <asm/hardirq.h> #include <asm/irq.h> #include <asm/div64.h> -#include <asm/cpu.h> #include <asm/setup.h> #include <asm/time.h> #include <asm/mc146818-time.h> #include <asm/msc01_ic.h> +#include <asm/gic.h> #include <asm/mips-boards/generic.h> #include <asm/mips-boards/prom.h> @@ -46,6 +44,7 @@ #include <asm/mips-boards/maltaint.h> unsigned long cpu_khz; +int gic_frequency; static int mips_cpu_timer_irq; static int mips_cpu_perf_irq; @@ -61,44 +60,50 @@ static void mips_perf_dispatch(void) do_IRQ(mips_cpu_perf_irq); } +static unsigned int freqround(unsigned int freq, unsigned int amount) +{ + freq += amount; + freq -= freq % (amount*2); + return freq; +} + /* - * Estimate CPU frequency. Sets mips_hpt_frequency as a side-effect + * Estimate CPU and GIC frequencies. */ -static unsigned int __init estimate_cpu_frequency(void) +static void __init estimate_frequencies(void) { - unsigned int prid = read_c0_prid() & 0xffff00; - unsigned int count; - unsigned long flags; - unsigned int start; + unsigned int count, start; + unsigned int giccount = 0, gicstart = 0; local_irq_save(flags); - /* Start counter exactly on falling edge of update flag */ + /* Start counter exactly on falling edge of update flag. */ while (CMOS_READ(RTC_REG_A) & RTC_UIP); while (!(CMOS_READ(RTC_REG_A) & RTC_UIP)); - /* Start r4k counter. */ + /* Initialize counters. */ start = read_c0_count(); + if (gic_present) + GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_31_00), gicstart); - /* Read counter exactly on falling edge of update flag */ + /* Read counter exactly on falling edge of update flag. */ while (CMOS_READ(RTC_REG_A) & RTC_UIP); while (!(CMOS_READ(RTC_REG_A) & RTC_UIP)); - count = read_c0_count() - start; + count = read_c0_count(); + if (gic_present) + GICREAD(GIC_REG(SHARED, GIC_SH_COUNTER_31_00), giccount); - /* restore interrupts */ local_irq_restore(flags); - mips_hpt_frequency = count; - if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) && - (prid != (PRID_COMP_MIPS | PRID_IMP_25KF))) - count *= 2; - - count += 5000; /* round */ - count -= count%10000; + count -= start; + if (gic_present) + giccount -= gicstart; - return count; + mips_hpt_frequency = count; + if (gic_present) + gic_frequency = giccount; } void read_persistent_clock(struct timespec *ts) @@ -144,22 +149,34 @@ unsigned int __cpuinit get_c0_compare_int(void) void __init plat_time_init(void) { - unsigned int est_freq; - - /* Set Data mode - binary. */ - CMOS_WRITE(CMOS_READ(RTC_CONTROL) | RTC_DM_BINARY, RTC_CONTROL); - - est_freq = estimate_cpu_frequency(); + unsigned int prid = read_c0_prid() & 0xffff00; + unsigned int freq; - printk("CPU frequency %d.%02d MHz\n", est_freq/1000000, - (est_freq%1000000)*100/1000000); + estimate_frequencies(); - cpu_khz = est_freq / 1000; + freq = mips_hpt_frequency; + if ((prid != (PRID_COMP_MIPS | PRID_IMP_20KC)) && + (prid != (PRID_COMP_MIPS | PRID_IMP_25KF))) + freq *= 2; + freq = freqround(freq, 5000); + pr_debug("CPU frequency %d.%02d MHz\n", freq/1000000, + (freq%1000000)*100/1000000); + cpu_khz = freq / 1000; + + if (gic_present) { + freq = freqround(gic_frequency, 5000); + pr_debug("GIC frequency %d.%02d MHz\n", freq/1000000, + (freq%1000000)*100/1000000); + gic_clocksource_init(gic_frequency); + } else + init_r4k_clocksource(); - mips_scroll_message(); -#ifdef CONFIG_I8253 /* Only Malta has a PIT */ +#ifdef CONFIG_I8253 + /* Only Malta has a PIT. */ setup_pit_timer(); #endif + mips_scroll_message(); + plat_perf_setup(); } |