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Diffstat (limited to 'arch/sh64/kernel/time.c')
| -rw-r--r-- | arch/sh64/kernel/time.c | 610 |
1 files changed, 610 insertions, 0 deletions
diff --git a/arch/sh64/kernel/time.c b/arch/sh64/kernel/time.c new file mode 100644 index 000000000000..6c84da3efc73 --- /dev/null +++ b/arch/sh64/kernel/time.c @@ -0,0 +1,610 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * arch/sh64/kernel/time.c + * + * Copyright (C) 2000, 2001 Paolo Alberelli + * Copyright (C) 2003, 2004 Paul Mundt + * Copyright (C) 2003 Richard Curnow + * + * Original TMU/RTC code taken from sh version. + * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka + * Some code taken from i386 version. + * Copyright (C) 1991, 1992, 1995 Linus Torvalds + */ + +#include <linux/config.h> +#include <linux/errno.h> +#include <linux/rwsem.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/param.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/time.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/profile.h> +#include <linux/smp.h> + +#include <asm/registers.h> /* required by inline __asm__ stmt. */ + +#include <asm/processor.h> +#include <asm/uaccess.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/delay.h> + +#include <linux/timex.h> +#include <linux/irq.h> +#include <asm/hardware.h> + +#define TMU_TOCR_INIT 0x00 +#define TMU0_TCR_INIT 0x0020 +#define TMU_TSTR_INIT 1 +#define TMU_TSTR_OFF 0 + +/* RCR1 Bits */ +#define RCR1_CF 0x80 /* Carry Flag */ +#define RCR1_CIE 0x10 /* Carry Interrupt Enable */ +#define RCR1_AIE 0x08 /* Alarm Interrupt Enable */ +#define RCR1_AF 0x01 /* Alarm Flag */ + +/* RCR2 Bits */ +#define RCR2_PEF 0x80 /* PEriodic interrupt Flag */ +#define RCR2_PESMASK 0x70 /* Periodic interrupt Set */ +#define RCR2_RTCEN 0x08 /* ENable RTC */ +#define RCR2_ADJ 0x04 /* ADJustment (30-second) */ +#define RCR2_RESET 0x02 /* Reset bit */ +#define RCR2_START 0x01 /* Start bit */ + +/* Clock, Power and Reset Controller */ +#define CPRC_BLOCK_OFF 0x01010000 +#define CPRC_BASE PHYS_PERIPHERAL_BLOCK + CPRC_BLOCK_OFF + +#define FRQCR (cprc_base+0x0) +#define WTCSR (cprc_base+0x0018) +#define STBCR (cprc_base+0x0030) + +/* Time Management Unit */ +#define TMU_BLOCK_OFF 0x01020000 +#define TMU_BASE PHYS_PERIPHERAL_BLOCK + TMU_BLOCK_OFF +#define TMU0_BASE tmu_base + 0x8 + (0xc * 0x0) +#define TMU1_BASE tmu_base + 0x8 + (0xc * 0x1) +#define TMU2_BASE tmu_base + 0x8 + (0xc * 0x2) + +#define TMU_TOCR tmu_base+0x0 /* Byte access */ +#define TMU_TSTR tmu_base+0x4 /* Byte access */ + +#define TMU0_TCOR TMU0_BASE+0x0 /* Long access */ +#define TMU0_TCNT TMU0_BASE+0x4 /* Long access */ +#define TMU0_TCR TMU0_BASE+0x8 /* Word access */ + +/* Real Time Clock */ +#define RTC_BLOCK_OFF 0x01040000 +#define RTC_BASE PHYS_PERIPHERAL_BLOCK + RTC_BLOCK_OFF + +#define R64CNT rtc_base+0x00 +#define RSECCNT rtc_base+0x04 +#define RMINCNT rtc_base+0x08 +#define RHRCNT rtc_base+0x0c +#define RWKCNT rtc_base+0x10 +#define RDAYCNT rtc_base+0x14 +#define RMONCNT rtc_base+0x18 +#define RYRCNT rtc_base+0x1c /* 16bit */ +#define RSECAR rtc_base+0x20 +#define RMINAR rtc_base+0x24 +#define RHRAR rtc_base+0x28 +#define RWKAR rtc_base+0x2c +#define RDAYAR rtc_base+0x30 +#define RMONAR rtc_base+0x34 +#define RCR1 rtc_base+0x38 +#define RCR2 rtc_base+0x3c + +#ifndef BCD_TO_BIN +#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10) +#endif + +#ifndef BIN_TO_BCD +#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10) +#endif + +#define TICK_SIZE (tick_nsec / 1000) + +extern unsigned long wall_jiffies; + +u64 jiffies_64 = INITIAL_JIFFIES; + +static unsigned long tmu_base, rtc_base; +unsigned long cprc_base; + +/* Variables to allow interpolation of time of day to resolution better than a + * jiffy. */ + +/* This is effectively protected by xtime_lock */ +static unsigned long ctc_last_interrupt; +static unsigned long long usecs_per_jiffy = 1000000/HZ; /* Approximation */ + +#define CTC_JIFFY_SCALE_SHIFT 40 + +/* 2**CTC_JIFFY_SCALE_SHIFT / ctc_ticks_per_jiffy */ +static unsigned long long scaled_recip_ctc_ticks_per_jiffy; + +/* Estimate number of microseconds that have elapsed since the last timer tick, + by scaling the delta that has occured in the CTC register. + + WARNING WARNING WARNING : This algorithm relies on the CTC decrementing at + the CPU clock rate. If the CPU sleeps, the CTC stops counting. Bear this + in mind if enabling SLEEP_WORKS in process.c. In that case, this algorithm + probably needs to use TMU.TCNT0 instead. This will work even if the CPU is + sleeping, though will be coarser. + + FIXME : What if usecs_per_tick is moving around too much, e.g. if an adjtime + is running or if the freq or tick arguments of adjtimex are modified after + we have calibrated the scaling factor? This will result in either a jump at + the end of a tick period, or a wrap backwards at the start of the next one, + if the application is reading the time of day often enough. I think we + ought to do better than this. For this reason, usecs_per_jiffy is left + separated out in the calculation below. This allows some future hook into + the adjtime-related stuff in kernel/timer.c to remove this hazard. + +*/ + +static unsigned long usecs_since_tick(void) +{ + unsigned long long current_ctc; + long ctc_ticks_since_interrupt; + unsigned long long ull_ctc_ticks_since_interrupt; + unsigned long result; + + unsigned long long mul1_out; + unsigned long long mul1_out_high; + unsigned long long mul2_out_low, mul2_out_high; + + /* Read CTC register */ + asm ("getcon cr62, %0" : "=r" (current_ctc)); + /* Note, the CTC counts down on each CPU clock, not up. + Note(2), use long type to get correct wraparound arithmetic when + the counter crosses zero. */ + ctc_ticks_since_interrupt = (long) ctc_last_interrupt - (long) current_ctc; + ull_ctc_ticks_since_interrupt = (unsigned long long) ctc_ticks_since_interrupt; + + /* Inline assembly to do 32x32x32->64 multiplier */ + asm volatile ("mulu.l %1, %2, %0" : + "=r" (mul1_out) : + "r" (ull_ctc_ticks_since_interrupt), "r" (usecs_per_jiffy)); + + mul1_out_high = mul1_out >> 32; + + asm volatile ("mulu.l %1, %2, %0" : + "=r" (mul2_out_low) : + "r" (mul1_out), "r" (scaled_recip_ctc_ticks_per_jiffy)); + +#if 1 + asm volatile ("mulu.l %1, %2, %0" : + "=r" (mul2_out_high) : + "r" (mul1_out_high), "r" (scaled_recip_ctc_ticks_per_jiffy)); +#endif + + result = (unsigned long) (((mul2_out_high << 32) + mul2_out_low) >> CTC_JIFFY_SCALE_SHIFT); + + return result; +} + +void do_gettimeofday(struct timeval *tv) +{ + unsigned long flags; + unsigned long seq; + unsigned long usec, sec; + + do { + seq = read_seqbegin_irqsave(&xtime_lock, flags); + usec = usecs_since_tick(); + { + unsigned long lost = jiffies - wall_jiffies; + + if (lost) + usec += lost * (1000000 / HZ); + } + + sec = xtime.tv_sec; + usec += xtime.tv_nsec / 1000; + } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); + + while (usec >= 1000000) { + usec -= 1000000; + sec++; + } + + tv->tv_sec = sec; + tv->tv_usec = usec; +} + +int do_settimeofday(struct timespec *tv) +{ + time_t wtm_sec, sec = tv->tv_sec; + long wtm_nsec, nsec = tv->tv_nsec; + + if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) + return -EINVAL; + + write_seqlock_irq(&xtime_lock); + /* + * This is revolting. We need to set "xtime" correctly. However, the + * value in this location is the value at the most recent update of + * wall time. Discover what correction gettimeofday() would have + * made, and then undo it! + */ + nsec -= 1000 * (usecs_since_tick() + + (jiffies - wall_jiffies) * (1000000 / HZ)); + + wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); + wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); + + set_normalized_timespec(&xtime, sec, nsec); + set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); + + time_adjust = 0; /* stop active adjtime() */ + time_status |= STA_UNSYNC; + time_maxerror = NTP_PHASE_LIMIT; + time_esterror = NTP_PHASE_LIMIT; + write_sequnlock_irq(&xtime_lock); + clock_was_set(); + + return 0; +} + +static int set_rtc_time(unsigned long nowtime) +{ + int retval = 0; + int real_seconds, real_minutes, cmos_minutes; + + ctrl_outb(RCR2_RESET, RCR2); /* Reset pre-scaler & stop RTC */ + + cmos_minutes = ctrl_inb(RMINCNT); + BCD_TO_BIN(cmos_minutes); + + /* + * since we're only adjusting minutes and seconds, + * don't interfere with hour overflow. This avoids + * messing with unknown time zones but requires your + * RTC not to be off by more than 15 minutes + */ + real_seconds = nowtime % 60; + real_minutes = nowtime / 60; + if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1) + real_minutes += 30; /* correct for half hour time zone */ + real_minutes %= 60; + + if (abs(real_minutes - cmos_minutes) < 30) { + BIN_TO_BCD(real_seconds); + BIN_TO_BCD(real_minutes); + ctrl_outb(real_seconds, RSECCNT); + ctrl_outb(real_minutes, RMINCNT); + } else { + printk(KERN_WARNING + "set_rtc_time: can't update from %d to %d\n", + cmos_minutes, real_minutes); + retval = -1; + } + + ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start RTC */ + + return retval; +} + +/* last time the RTC clock got updated */ +static long last_rtc_update = 0; + +/* + * timer_interrupt() needs to keep up the real-time clock, + * as well as call the "do_timer()" routine every clocktick + */ +static inline void do_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + unsigned long long current_ctc; + asm ("getcon cr62, %0" : "=r" (current_ctc)); + ctc_last_interrupt = (unsigned long) current_ctc; + + do_timer(regs); +#ifndef CONFIG_SMP + update_process_times(user_mode(regs)); +#endif + profile_tick(CPU_PROFILING, regs); + +#ifdef CONFIG_HEARTBEAT + { + extern void heartbeat(void); + + heartbeat(); + } +#endif + + /* + * If we have an externally synchronized Linux clock, then update + * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be + * called as close as possible to 500 ms before the new second starts. + */ + if ((time_status & STA_UNSYNC) == 0 && + xtime.tv_sec > last_rtc_update + 660 && + (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 && + (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) { + if (set_rtc_time(xtime.tv_sec) == 0) + last_rtc_update = xtime.tv_sec; + else + last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */ + } +} + +/* + * This is the same as the above, except we _also_ save the current + * Time Stamp Counter value at the time of the timer interrupt, so that + * we later on can estimate the time of day more exactly. + */ +static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + unsigned long timer_status; + + /* Clear UNF bit */ + timer_status = ctrl_inw(TMU0_TCR); + timer_status &= ~0x100; + ctrl_outw(timer_status, TMU0_TCR); + + /* + * Here we are in the timer irq handler. We just have irqs locally + * disabled but we don't know if the timer_bh is running on the other + * CPU. We need to avoid to SMP race with it. NOTE: we don' t need + * the irq version of write_lock because as just said we have irq + * locally disabled. -arca + */ + write_lock(&xtime_lock); + do_timer_interrupt(irq, NULL, regs); + write_unlock(&xtime_lock); + + return IRQ_HANDLED; +} + +static unsigned long get_rtc_time(void) +{ + unsigned int sec, min, hr, wk, day, mon, yr, yr100; + + again: + do { + ctrl_outb(0, RCR1); /* Clear CF-bit */ + sec = ctrl_inb(RSECCNT); + min = ctrl_inb(RMINCNT); + hr = ctrl_inb(RHRCNT); + wk = ctrl_inb(RWKCNT); + day = ctrl_inb(RDAYCNT); + mon = ctrl_inb(RMONCNT); + yr = ctrl_inw(RYRCNT); + yr100 = (yr >> 8); + yr &= 0xff; + } while ((ctrl_inb(RCR1) & RCR1_CF) != 0); + + BCD_TO_BIN(yr100); + BCD_TO_BIN(yr); + BCD_TO_BIN(mon); + BCD_TO_BIN(day); + BCD_TO_BIN(hr); + BCD_TO_BIN(min); + BCD_TO_BIN(sec); + + if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 || + hr > 23 || min > 59 || sec > 59) { + printk(KERN_ERR + "SH RTC: invalid value, resetting to 1 Jan 2000\n"); + ctrl_outb(RCR2_RESET, RCR2); /* Reset & Stop */ + ctrl_outb(0, RSECCNT); + ctrl_outb(0, RMINCNT); + ctrl_outb(0, RHRCNT); + ctrl_outb(6, RWKCNT); + ctrl_outb(1, RDAYCNT); + ctrl_outb(1, RMONCNT); + ctrl_outw(0x2000, RYRCNT); + ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start */ + goto again; + } + + return mktime(yr100 * 100 + yr, mon, day, hr, min, sec); +} + +static __init unsigned int get_cpu_hz(void) +{ + unsigned int count; + unsigned long __dummy; + unsigned long ctc_val_init, ctc_val; + + /* + ** Regardless the toolchain, force the compiler to use the + ** arbitrary register r3 as a clock tick counter. + ** NOTE: r3 must be in accordance with rtc_interrupt() + */ + register unsigned long long __rtc_irq_flag __asm__ ("r3"); + + local_irq_enable(); + do {} while (ctrl_inb(R64CNT) != 0); + ctrl_outb(RCR1_CIE, RCR1); /* Enable carry interrupt */ + + /* + * r3 is arbitrary. CDC does not support "=z". + */ + ctc_val_init = 0xffffffff; + ctc_val = ctc_val_init; + + asm volatile("gettr tr0, %1\n\t" + "putcon %0, " __CTC "\n\t" + "and %2, r63, %2\n\t" + "pta $+4, tr0\n\t" + "beq/l %2, r63, tr0\n\t" + "ptabs %1, tr0\n\t" + "getcon " __CTC ", %0\n\t" + : "=r"(ctc_val), "=r" (__dummy), "=r" (__rtc_irq_flag) + : "0" (0)); + local_irq_disable(); + /* + * SH-3: + * CPU clock = 4 stages * loop + * tst rm,rm if id ex + * bt/s 1b if id ex + * add #1,rd if id ex + * (if) pipe line stole + * tst rm,rm if id ex + * .... + * + * + * SH-4: + * CPU clock = 6 stages * loop + * I don't know why. + * .... + * + * SH-5: + * Use CTC register to count. This approach returns the right value + * even if the I-cache is disabled (e.g. whilst debugging.) + * + */ + + count = ctc_val_init - ctc_val; /* CTC counts down */ + +#if defined (CONFIG_SH_SIMULATOR) + /* + * Let's pretend we are a 5MHz SH-5 to avoid a too + * little timer interval. Also to keep delay + * calibration within a reasonable time. + */ + return 5000000; +#else + /* + * This really is count by the number of clock cycles + * by the ratio between a complete R64CNT + * wrap-around (128) and CUI interrupt being raised (64). + */ + return count*2; +#endif +} + +static irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + ctrl_outb(0, RCR1); /* Disable Carry Interrupts */ + regs->regs[3] = 1; /* Using r3 */ + + return IRQ_HANDLED; +} + +static struct irqaction irq0 = { timer_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "timer", NULL, NULL}; +static struct irqaction irq1 = { rtc_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "rtc", NULL, NULL}; + +void __init time_init(void) +{ + unsigned int cpu_clock, master_clock, bus_clock, module_clock; + unsigned long interval; + unsigned long frqcr, ifc, pfc; + static int ifc_table[] = { 2, 4, 6, 8, 10, 12, 16, 24 }; +#define bfc_table ifc_table /* Same */ +#define pfc_table ifc_table /* Same */ + + tmu_base = onchip_remap(TMU_BASE, 1024, "TMU"); + if (!tmu_base) { + panic("Unable to remap TMU\n"); + } + + rtc_base = onchip_remap(RTC_BASE, 1024, "RTC"); + if (!rtc_base) { + panic("Unable to remap RTC\n"); + } + + cprc_base = onchip_remap(CPRC_BASE, 1024, "CPRC"); + if (!cprc_base) { + panic("Unable to remap CPRC\n"); + } + + xtime.tv_sec = get_rtc_time(); + xtime.tv_nsec = 0; + + setup_irq(TIMER_IRQ, &irq0); + setup_irq(RTC_IRQ, &irq1); + + /* Check how fast it is.. */ + cpu_clock = get_cpu_hz(); + + /* Note careful order of operations to maintain reasonable precision and avoid overflow. */ + scaled_recip_ctc_ticks_per_jiffy = ((1ULL << CTC_JIFFY_SCALE_SHIFT) / (unsigned long long)(cpu_clock / HZ)); + + disable_irq(RTC_IRQ); + + printk("CPU clock: %d.%02dMHz\n", + (cpu_clock / 1000000), (cpu_clock % 1000000)/10000); + { + unsigned short bfc; + frqcr = ctrl_inl(FRQCR); + ifc = ifc_table[(frqcr>> 6) & 0x0007]; + bfc = bfc_table[(frqcr>> 3) & 0x0007]; + pfc = pfc_table[(frqcr>> 12) & 0x0007]; + master_clock = cpu_clock * ifc; + bus_clock = master_clock/bfc; + } + + printk("Bus clock: %d.%02dMHz\n", + (bus_clock/1000000), (bus_clock % 1000000)/10000); + module_clock = master_clock/pfc; + printk("Module clock: %d.%02dMHz\n", + (module_clock/1000000), (module_clock % 1000000)/10000); + interval = (module_clock/(HZ*4)); + + printk("Interval = %ld\n", interval); + + current_cpu_data.cpu_clock = cpu_clock; + current_cpu_data.master_clock = master_clock; + current_cpu_data.bus_clock = bus_clock; + current_cpu_data.module_clock = module_clock; + + /* Start TMU0 */ + ctrl_outb(TMU_TSTR_OFF, TMU_TSTR); + ctrl_outb(TMU_TOCR_INIT, TMU_TOCR); + ctrl_outw(TMU0_TCR_INIT, TMU0_TCR); + ctrl_outl(interval, TMU0_TCOR); + ctrl_outl(interval, TMU0_TCNT); + ctrl_outb(TMU_TSTR_INIT, TMU_TSTR); +} + +void enter_deep_standby(void) +{ + /* Disable watchdog timer */ + ctrl_outl(0xa5000000, WTCSR); + /* Configure deep standby on sleep */ + ctrl_outl(0x03, STBCR); + +#ifdef CONFIG_SH_ALPHANUMERIC + { + extern void mach_alphanum(int position, unsigned char value); + extern void mach_alphanum_brightness(int setting); + char halted[] = "Halted. "; + int i; + mach_alphanum_brightness(6); /* dimmest setting above off */ + for (i=0; i<8; i++) { + mach_alphanum(i, halted[i]); + } + asm __volatile__ ("synco"); + } +#endif + + asm __volatile__ ("sleep"); + asm __volatile__ ("synci"); + asm __volatile__ ("nop"); + asm __volatile__ ("nop"); + asm __volatile__ ("nop"); + asm __volatile__ ("nop"); + panic("Unexpected wakeup!\n"); +} + +/* + * Scheduler clock - returns current time in nanosec units. + */ +unsigned long long sched_clock(void) +{ + return (unsigned long long)jiffies * (1000000000 / HZ); +} + |