From 16b7b2ac0148e839da86af8747b6fa4aad43a9b7 Mon Sep 17 00:00:00 2001 From: Atsushi Nemoto Date: Tue, 24 Oct 2006 00:21:27 +0900 Subject: [MIPS] Fixup migration to GENERIC_TIME Since we already moved to GENERIC_TIME, we should implement alternatives of old do_gettimeoffset routines to get sub-jiffies resolution from gettimeofday(). This patch includes: * MIPS clocksource support (based on works by Manish Lachwani). * remove unused gettimeoffset routines and related codes. * remove unised 64bit do_div64_32(). * simplify mips_hpt_init. (no argument needed, __init tag) * simplify c0_hpt_timer_init. (no need to write to c0_count) * remove some hpt_init routines. * mips_hpt_mask variable to specify bitmask of hpt value. * convert jmr3927_do_gettimeoffset to jmr3927_hpt_read. * convert ip27_do_gettimeoffset to ip27_hpt_read. * convert bcm1480_do_gettimeoffset to bcm1480_hpt_read. * simplify sb1250 hpt functions. (no need to subtract and shift) Signed-off-by: Atsushi Nemoto Signed-off-by: Ralf Baechle --- arch/mips/au1000/common/time.c | 98 ------------------------------------------ 1 file changed, 98 deletions(-) (limited to 'arch/mips/au1000/common/time.c') diff --git a/arch/mips/au1000/common/time.c b/arch/mips/au1000/common/time.c index 6768638883ea..fa1c62f05515 100644 --- a/arch/mips/au1000/common/time.c +++ b/arch/mips/au1000/common/time.c @@ -53,9 +53,6 @@ static unsigned long r4k_cur; /* What counter should be at next timer irq */ int no_au1xxx_32khz; extern int allow_au1k_wait; /* default off for CP0 Counter */ -/* Cycle counter value at the previous timer interrupt.. */ -static unsigned int timerhi = 0, timerlo = 0; - #ifdef CONFIG_PM #if HZ < 100 || HZ > 1000 #error "unsupported HZ value! Must be in [100,1000]" @@ -90,10 +87,6 @@ void mips_timer_interrupt(void) goto null; do { - count = read_c0_count(); - timerhi += (count < timerlo); /* Wrap around */ - timerlo = count; - kstat_this_cpu.irqs[irq]++; do_timer(1); #ifndef CONFIG_SMP @@ -297,88 +290,6 @@ unsigned long cal_r4koff(void) return (cpu_speed / HZ); } -/* This is for machines which generate the exact clock. */ -#define USECS_PER_JIFFY (1000000/HZ) -#define USECS_PER_JIFFY_FRAC (0x100000000LL*1000000/HZ&0xffffffff) - -static unsigned long -div64_32(unsigned long v1, unsigned long v2, unsigned long v3) -{ - unsigned long r0; - do_div64_32(r0, v1, v2, v3); - return r0; -} - -static unsigned long do_fast_cp0_gettimeoffset(void) -{ - u32 count; - unsigned long res, tmp; - unsigned long r0; - - /* Last jiffy when do_fast_gettimeoffset() was called. */ - static unsigned long last_jiffies=0; - unsigned long quotient; - - /* - * Cached "1/(clocks per usec)*2^32" value. - * It has to be recalculated once each jiffy. - */ - static unsigned long cached_quotient=0; - - tmp = jiffies; - - quotient = cached_quotient; - - if (tmp && last_jiffies != tmp) { - last_jiffies = tmp; - if (last_jiffies != 0) { - r0 = div64_32(timerhi, timerlo, tmp); - quotient = div64_32(USECS_PER_JIFFY, USECS_PER_JIFFY_FRAC, r0); - cached_quotient = quotient; - } - } - - /* Get last timer tick in absolute kernel time */ - count = read_c0_count(); - - /* .. relative to previous jiffy (32 bits is enough) */ - count -= timerlo; - - __asm__("multu\t%1,%2\n\t" - "mfhi\t%0" - : "=r" (res) - : "r" (count), "r" (quotient) - : "hi", "lo", GCC_REG_ACCUM); - - /* - * Due to possible jiffies inconsistencies, we need to check - * the result so that we'll get a timer that is monotonic. - */ - if (res >= USECS_PER_JIFFY) - res = USECS_PER_JIFFY-1; - - return res; -} - -#ifdef CONFIG_PM -static unsigned long do_fast_pm_gettimeoffset(void) -{ - unsigned long pc0; - unsigned long offset; - - pc0 = au_readl(SYS_TOYREAD); - au_sync(); - offset = pc0 - last_pc0; - if (offset > 2*MATCH20_INC) { - printk("huge offset %x, last_pc0 %x last_match20 %x pc0 %x\n", - (unsigned)offset, (unsigned)last_pc0, - (unsigned)last_match20, (unsigned)pc0); - } - offset = (unsigned long)((offset * 305) / 10); - return offset; -} -#endif - void __init plat_timer_setup(struct irqaction *irq) { unsigned int est_freq; @@ -416,7 +327,6 @@ void __init plat_timer_setup(struct irqaction *irq) unsigned int c0_status; printk("WARNING: no 32KHz clock found.\n"); - do_gettimeoffset = do_fast_cp0_gettimeoffset; /* Ensure we get CPO_COUNTER interrupts. */ @@ -441,19 +351,11 @@ void __init plat_timer_setup(struct irqaction *irq) while (au_readl(SYS_COUNTER_CNTRL) & SYS_CNTRL_M20); startup_match20_interrupt(counter0_irq); - do_gettimeoffset = do_fast_pm_gettimeoffset; - /* We can use the real 'wait' instruction. */ allow_au1k_wait = 1; } -#else - /* We have to do this here instead of in timer_init because - * the generic code in arch/mips/kernel/time.c will write - * over our function pointer. - */ - do_gettimeoffset = do_fast_cp0_gettimeoffset; #endif } -- cgit v1.2.2