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-rw-r--r--arch/sh64/kernel/time.c610
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diff --git a/arch/sh64/kernel/time.c b/arch/sh64/kernel/time.c
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+/*
+ * 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);
+}
+