2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
6 * arch/sh64/kernel/time.c
8 * Copyright (C) 2000, 2001 Paolo Alberelli
9 * Copyright (C) 2003, 2004 Paul Mundt
10 * Copyright (C) 2003 Richard Curnow
12 * Original TMU/RTC code taken from sh version.
13 * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka
14 * Some code taken from i386 version.
15 * Copyright (C) 1991, 1992, 1995 Linus Torvalds
18 #include <linux/config.h>
19 #include <linux/errno.h>
20 #include <linux/rwsem.h>
21 #include <linux/sched.h>
22 #include <linux/kernel.h>
23 #include <linux/param.h>
24 #include <linux/string.h>
26 #include <linux/interrupt.h>
27 #include <linux/time.h>
28 #include <linux/delay.h>
29 #include <linux/init.h>
30 #include <linux/profile.h>
31 #include <linux/smp.h>
33 #include <asm/registers.h> /* required by inline __asm__ stmt. */
35 #include <asm/processor.h>
36 #include <asm/uaccess.h>
39 #include <asm/delay.h>
41 #include <linux/timex.h>
42 #include <linux/irq.h>
43 #include <asm/hardware.h>
45 #define TMU_TOCR_INIT 0x00
46 #define TMU0_TCR_INIT 0x0020
47 #define TMU_TSTR_INIT 1
48 #define TMU_TSTR_OFF 0
51 #define RCR1_CF 0x80 /* Carry Flag */
52 #define RCR1_CIE 0x10 /* Carry Interrupt Enable */
53 #define RCR1_AIE 0x08 /* Alarm Interrupt Enable */
54 #define RCR1_AF 0x01 /* Alarm Flag */
57 #define RCR2_PEF 0x80 /* PEriodic interrupt Flag */
58 #define RCR2_PESMASK 0x70 /* Periodic interrupt Set */
59 #define RCR2_RTCEN 0x08 /* ENable RTC */
60 #define RCR2_ADJ 0x04 /* ADJustment (30-second) */
61 #define RCR2_RESET 0x02 /* Reset bit */
62 #define RCR2_START 0x01 /* Start bit */
64 /* Clock, Power and Reset Controller */
65 #define CPRC_BLOCK_OFF 0x01010000
66 #define CPRC_BASE PHYS_PERIPHERAL_BLOCK + CPRC_BLOCK_OFF
68 #define FRQCR (cprc_base+0x0)
69 #define WTCSR (cprc_base+0x0018)
70 #define STBCR (cprc_base+0x0030)
72 /* Time Management Unit */
73 #define TMU_BLOCK_OFF 0x01020000
74 #define TMU_BASE PHYS_PERIPHERAL_BLOCK + TMU_BLOCK_OFF
75 #define TMU0_BASE tmu_base + 0x8 + (0xc * 0x0)
76 #define TMU1_BASE tmu_base + 0x8 + (0xc * 0x1)
77 #define TMU2_BASE tmu_base + 0x8 + (0xc * 0x2)
79 #define TMU_TOCR tmu_base+0x0 /* Byte access */
80 #define TMU_TSTR tmu_base+0x4 /* Byte access */
82 #define TMU0_TCOR TMU0_BASE+0x0 /* Long access */
83 #define TMU0_TCNT TMU0_BASE+0x4 /* Long access */
84 #define TMU0_TCR TMU0_BASE+0x8 /* Word access */
87 #define RTC_BLOCK_OFF 0x01040000
88 #define RTC_BASE PHYS_PERIPHERAL_BLOCK + RTC_BLOCK_OFF
90 #define R64CNT rtc_base+0x00
91 #define RSECCNT rtc_base+0x04
92 #define RMINCNT rtc_base+0x08
93 #define RHRCNT rtc_base+0x0c
94 #define RWKCNT rtc_base+0x10
95 #define RDAYCNT rtc_base+0x14
96 #define RMONCNT rtc_base+0x18
97 #define RYRCNT rtc_base+0x1c /* 16bit */
98 #define RSECAR rtc_base+0x20
99 #define RMINAR rtc_base+0x24
100 #define RHRAR rtc_base+0x28
101 #define RWKAR rtc_base+0x2c
102 #define RDAYAR rtc_base+0x30
103 #define RMONAR rtc_base+0x34
104 #define RCR1 rtc_base+0x38
105 #define RCR2 rtc_base+0x3c
108 #define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10)
112 #define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10)
115 #define TICK_SIZE (tick_nsec / 1000)
117 extern unsigned long wall_jiffies;
119 static unsigned long tmu_base, rtc_base;
120 unsigned long cprc_base;
122 /* Variables to allow interpolation of time of day to resolution better than a
125 /* This is effectively protected by xtime_lock */
126 static unsigned long ctc_last_interrupt;
127 static unsigned long long usecs_per_jiffy = 1000000/HZ; /* Approximation */
129 #define CTC_JIFFY_SCALE_SHIFT 40
131 /* 2**CTC_JIFFY_SCALE_SHIFT / ctc_ticks_per_jiffy */
132 static unsigned long long scaled_recip_ctc_ticks_per_jiffy;
134 /* Estimate number of microseconds that have elapsed since the last timer tick,
135 by scaling the delta that has occured in the CTC register.
137 WARNING WARNING WARNING : This algorithm relies on the CTC decrementing at
138 the CPU clock rate. If the CPU sleeps, the CTC stops counting. Bear this
139 in mind if enabling SLEEP_WORKS in process.c. In that case, this algorithm
140 probably needs to use TMU.TCNT0 instead. This will work even if the CPU is
141 sleeping, though will be coarser.
143 FIXME : What if usecs_per_tick is moving around too much, e.g. if an adjtime
144 is running or if the freq or tick arguments of adjtimex are modified after
145 we have calibrated the scaling factor? This will result in either a jump at
146 the end of a tick period, or a wrap backwards at the start of the next one,
147 if the application is reading the time of day often enough. I think we
148 ought to do better than this. For this reason, usecs_per_jiffy is left
149 separated out in the calculation below. This allows some future hook into
150 the adjtime-related stuff in kernel/timer.c to remove this hazard.
154 static unsigned long usecs_since_tick(void)
156 unsigned long long current_ctc;
157 long ctc_ticks_since_interrupt;
158 unsigned long long ull_ctc_ticks_since_interrupt;
159 unsigned long result;
161 unsigned long long mul1_out;
162 unsigned long long mul1_out_high;
163 unsigned long long mul2_out_low, mul2_out_high;
165 /* Read CTC register */
166 asm ("getcon cr62, %0" : "=r" (current_ctc));
167 /* Note, the CTC counts down on each CPU clock, not up.
168 Note(2), use long type to get correct wraparound arithmetic when
169 the counter crosses zero. */
170 ctc_ticks_since_interrupt = (long) ctc_last_interrupt - (long) current_ctc;
171 ull_ctc_ticks_since_interrupt = (unsigned long long) ctc_ticks_since_interrupt;
173 /* Inline assembly to do 32x32x32->64 multiplier */
174 asm volatile ("mulu.l %1, %2, %0" :
176 "r" (ull_ctc_ticks_since_interrupt), "r" (usecs_per_jiffy));
178 mul1_out_high = mul1_out >> 32;
180 asm volatile ("mulu.l %1, %2, %0" :
181 "=r" (mul2_out_low) :
182 "r" (mul1_out), "r" (scaled_recip_ctc_ticks_per_jiffy));
185 asm volatile ("mulu.l %1, %2, %0" :
186 "=r" (mul2_out_high) :
187 "r" (mul1_out_high), "r" (scaled_recip_ctc_ticks_per_jiffy));
190 result = (unsigned long) (((mul2_out_high << 32) + mul2_out_low) >> CTC_JIFFY_SCALE_SHIFT);
195 void do_gettimeofday(struct timeval *tv)
199 unsigned long usec, sec;
202 seq = read_seqbegin_irqsave(&xtime_lock, flags);
203 usec = usecs_since_tick();
205 unsigned long lost = jiffies - wall_jiffies;
208 usec += lost * (1000000 / HZ);
212 usec += xtime.tv_nsec / 1000;
213 } while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
215 while (usec >= 1000000) {
224 int do_settimeofday(struct timespec *tv)
226 time_t wtm_sec, sec = tv->tv_sec;
227 long wtm_nsec, nsec = tv->tv_nsec;
229 if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
232 write_seqlock_irq(&xtime_lock);
234 * This is revolting. We need to set "xtime" correctly. However, the
235 * value in this location is the value at the most recent update of
236 * wall time. Discover what correction gettimeofday() would have
237 * made, and then undo it!
239 nsec -= 1000 * (usecs_since_tick() +
240 (jiffies - wall_jiffies) * (1000000 / HZ));
242 wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec);
243 wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec);
245 set_normalized_timespec(&xtime, sec, nsec);
246 set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec);
249 write_sequnlock_irq(&xtime_lock);
254 EXPORT_SYMBOL(do_settimeofday);
256 static int set_rtc_time(unsigned long nowtime)
259 int real_seconds, real_minutes, cmos_minutes;
261 ctrl_outb(RCR2_RESET, RCR2); /* Reset pre-scaler & stop RTC */
263 cmos_minutes = ctrl_inb(RMINCNT);
264 BCD_TO_BIN(cmos_minutes);
267 * since we're only adjusting minutes and seconds,
268 * don't interfere with hour overflow. This avoids
269 * messing with unknown time zones but requires your
270 * RTC not to be off by more than 15 minutes
272 real_seconds = nowtime % 60;
273 real_minutes = nowtime / 60;
274 if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1)
275 real_minutes += 30; /* correct for half hour time zone */
278 if (abs(real_minutes - cmos_minutes) < 30) {
279 BIN_TO_BCD(real_seconds);
280 BIN_TO_BCD(real_minutes);
281 ctrl_outb(real_seconds, RSECCNT);
282 ctrl_outb(real_minutes, RMINCNT);
285 "set_rtc_time: can't update from %d to %d\n",
286 cmos_minutes, real_minutes);
290 ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start RTC */
295 /* last time the RTC clock got updated */
296 static long last_rtc_update = 0;
299 * timer_interrupt() needs to keep up the real-time clock,
300 * as well as call the "do_timer()" routine every clocktick
302 static inline void do_timer_interrupt(int irq, struct pt_regs *regs)
304 unsigned long long current_ctc;
305 asm ("getcon cr62, %0" : "=r" (current_ctc));
306 ctc_last_interrupt = (unsigned long) current_ctc;
310 update_process_times(user_mode(regs));
312 profile_tick(CPU_PROFILING, regs);
314 #ifdef CONFIG_HEARTBEAT
316 extern void heartbeat(void);
323 * If we have an externally synchronized Linux clock, then update
324 * RTC clock accordingly every ~11 minutes. Set_rtc_mmss() has to be
325 * called as close as possible to 500 ms before the new second starts.
328 xtime.tv_sec > last_rtc_update + 660 &&
329 (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
330 (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
331 if (set_rtc_time(xtime.tv_sec) == 0)
332 last_rtc_update = xtime.tv_sec;
334 last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
339 * This is the same as the above, except we _also_ save the current
340 * Time Stamp Counter value at the time of the timer interrupt, so that
341 * we later on can estimate the time of day more exactly.
343 static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
345 unsigned long timer_status;
348 timer_status = ctrl_inw(TMU0_TCR);
349 timer_status &= ~0x100;
350 ctrl_outw(timer_status, TMU0_TCR);
353 * Here we are in the timer irq handler. We just have irqs locally
354 * disabled but we don't know if the timer_bh is running on the other
355 * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
356 * the irq version of write_lock because as just said we have irq
357 * locally disabled. -arca
359 write_lock(&xtime_lock);
360 do_timer_interrupt(irq, regs);
361 write_unlock(&xtime_lock);
366 static unsigned long get_rtc_time(void)
368 unsigned int sec, min, hr, wk, day, mon, yr, yr100;
372 ctrl_outb(0, RCR1); /* Clear CF-bit */
373 sec = ctrl_inb(RSECCNT);
374 min = ctrl_inb(RMINCNT);
375 hr = ctrl_inb(RHRCNT);
376 wk = ctrl_inb(RWKCNT);
377 day = ctrl_inb(RDAYCNT);
378 mon = ctrl_inb(RMONCNT);
379 yr = ctrl_inw(RYRCNT);
382 } while ((ctrl_inb(RCR1) & RCR1_CF) != 0);
392 if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 ||
393 hr > 23 || min > 59 || sec > 59) {
395 "SH RTC: invalid value, resetting to 1 Jan 2000\n");
396 ctrl_outb(RCR2_RESET, RCR2); /* Reset & Stop */
397 ctrl_outb(0, RSECCNT);
398 ctrl_outb(0, RMINCNT);
399 ctrl_outb(0, RHRCNT);
400 ctrl_outb(6, RWKCNT);
401 ctrl_outb(1, RDAYCNT);
402 ctrl_outb(1, RMONCNT);
403 ctrl_outw(0x2000, RYRCNT);
404 ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start */
408 return mktime(yr100 * 100 + yr, mon, day, hr, min, sec);
411 static __init unsigned int get_cpu_hz(void)
414 unsigned long __dummy;
415 unsigned long ctc_val_init, ctc_val;
418 ** Regardless the toolchain, force the compiler to use the
419 ** arbitrary register r3 as a clock tick counter.
420 ** NOTE: r3 must be in accordance with rtc_interrupt()
422 register unsigned long long __rtc_irq_flag __asm__ ("r3");
425 do {} while (ctrl_inb(R64CNT) != 0);
426 ctrl_outb(RCR1_CIE, RCR1); /* Enable carry interrupt */
429 * r3 is arbitrary. CDC does not support "=z".
431 ctc_val_init = 0xffffffff;
432 ctc_val = ctc_val_init;
434 asm volatile("gettr tr0, %1\n\t"
435 "putcon %0, " __CTC "\n\t"
436 "and %2, r63, %2\n\t"
438 "beq/l %2, r63, tr0\n\t"
440 "getcon " __CTC ", %0\n\t"
441 : "=r"(ctc_val), "=r" (__dummy), "=r" (__rtc_irq_flag)
446 * CPU clock = 4 stages * loop
450 * (if) pipe line stole
456 * CPU clock = 6 stages * loop
461 * Use CTC register to count. This approach returns the right value
462 * even if the I-cache is disabled (e.g. whilst debugging.)
466 count = ctc_val_init - ctc_val; /* CTC counts down */
468 #if defined (CONFIG_SH_SIMULATOR)
470 * Let's pretend we are a 5MHz SH-5 to avoid a too
471 * little timer interval. Also to keep delay
472 * calibration within a reasonable time.
477 * This really is count by the number of clock cycles
478 * by the ratio between a complete R64CNT
479 * wrap-around (128) and CUI interrupt being raised (64).
485 static irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
487 ctrl_outb(0, RCR1); /* Disable Carry Interrupts */
488 regs->regs[3] = 1; /* Using r3 */
493 static struct irqaction irq0 = { timer_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "timer", NULL, NULL};
494 static struct irqaction irq1 = { rtc_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "rtc", NULL, NULL};
496 void __init time_init(void)
498 unsigned int cpu_clock, master_clock, bus_clock, module_clock;
499 unsigned long interval;
500 unsigned long frqcr, ifc, pfc;
501 static int ifc_table[] = { 2, 4, 6, 8, 10, 12, 16, 24 };
502 #define bfc_table ifc_table /* Same */
503 #define pfc_table ifc_table /* Same */
505 tmu_base = onchip_remap(TMU_BASE, 1024, "TMU");
507 panic("Unable to remap TMU\n");
510 rtc_base = onchip_remap(RTC_BASE, 1024, "RTC");
512 panic("Unable to remap RTC\n");
515 cprc_base = onchip_remap(CPRC_BASE, 1024, "CPRC");
517 panic("Unable to remap CPRC\n");
520 xtime.tv_sec = get_rtc_time();
523 setup_irq(TIMER_IRQ, &irq0);
524 setup_irq(RTC_IRQ, &irq1);
526 /* Check how fast it is.. */
527 cpu_clock = get_cpu_hz();
529 /* Note careful order of operations to maintain reasonable precision and avoid overflow. */
530 scaled_recip_ctc_ticks_per_jiffy = ((1ULL << CTC_JIFFY_SCALE_SHIFT) / (unsigned long long)(cpu_clock / HZ));
532 disable_irq(RTC_IRQ);
534 printk("CPU clock: %d.%02dMHz\n",
535 (cpu_clock / 1000000), (cpu_clock % 1000000)/10000);
538 frqcr = ctrl_inl(FRQCR);
539 ifc = ifc_table[(frqcr>> 6) & 0x0007];
540 bfc = bfc_table[(frqcr>> 3) & 0x0007];
541 pfc = pfc_table[(frqcr>> 12) & 0x0007];
542 master_clock = cpu_clock * ifc;
543 bus_clock = master_clock/bfc;
546 printk("Bus clock: %d.%02dMHz\n",
547 (bus_clock/1000000), (bus_clock % 1000000)/10000);
548 module_clock = master_clock/pfc;
549 printk("Module clock: %d.%02dMHz\n",
550 (module_clock/1000000), (module_clock % 1000000)/10000);
551 interval = (module_clock/(HZ*4));
553 printk("Interval = %ld\n", interval);
555 current_cpu_data.cpu_clock = cpu_clock;
556 current_cpu_data.master_clock = master_clock;
557 current_cpu_data.bus_clock = bus_clock;
558 current_cpu_data.module_clock = module_clock;
561 ctrl_outb(TMU_TSTR_OFF, TMU_TSTR);
562 ctrl_outb(TMU_TOCR_INIT, TMU_TOCR);
563 ctrl_outw(TMU0_TCR_INIT, TMU0_TCR);
564 ctrl_outl(interval, TMU0_TCOR);
565 ctrl_outl(interval, TMU0_TCNT);
566 ctrl_outb(TMU_TSTR_INIT, TMU_TSTR);
569 void enter_deep_standby(void)
571 /* Disable watchdog timer */
572 ctrl_outl(0xa5000000, WTCSR);
573 /* Configure deep standby on sleep */
574 ctrl_outl(0x03, STBCR);
576 #ifdef CONFIG_SH_ALPHANUMERIC
578 extern void mach_alphanum(int position, unsigned char value);
579 extern void mach_alphanum_brightness(int setting);
580 char halted[] = "Halted. ";
582 mach_alphanum_brightness(6); /* dimmest setting above off */
583 for (i=0; i<8; i++) {
584 mach_alphanum(i, halted[i]);
586 asm __volatile__ ("synco");
590 asm __volatile__ ("sleep");
591 asm __volatile__ ("synci");
592 asm __volatile__ ("nop");
593 asm __volatile__ ("nop");
594 asm __volatile__ ("nop");
595 asm __volatile__ ("nop");
596 panic("Unexpected wakeup!\n");
600 * Scheduler clock - returns current time in nanosec units.
602 unsigned long long sched_clock(void)
604 return (unsigned long long)jiffies * (1000000000 / HZ);