Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/m32r/kernel/time.c |
| 3 | * |
| 4 | * Copyright (c) 2001, 2002 Hiroyuki Kondo, Hirokazu Takata, |
| 5 | * Hitoshi Yamamoto |
| 6 | * Taken from i386 version. |
| 7 | * Copyright (C) 1991, 1992, 1995 Linus Torvalds |
| 8 | * Copyright (C) 1996, 1997, 1998 Ralf Baechle |
| 9 | * |
| 10 | * This file contains the time handling details for PC-style clocks as |
| 11 | * found in some MIPS systems. |
| 12 | * |
| 13 | * Some code taken from sh version. |
| 14 | * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka |
| 15 | * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> |
| 16 | */ |
| 17 | |
| 18 | #undef DEBUG_TIMER |
| 19 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/errno.h> |
| 21 | #include <linux/init.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/sched.h> |
| 24 | #include <linux/kernel.h> |
| 25 | #include <linux/param.h> |
| 26 | #include <linux/string.h> |
| 27 | #include <linux/mm.h> |
| 28 | #include <linux/interrupt.h> |
| 29 | #include <linux/profile.h> |
| 30 | |
| 31 | #include <asm/io.h> |
| 32 | #include <asm/m32r.h> |
| 33 | |
| 34 | #include <asm/hw_irq.h> |
| 35 | |
| 36 | #ifdef CONFIG_SMP |
Al Viro | 9c8e7f5 | 2006-10-07 16:29:18 +0100 | [diff] [blame] | 37 | extern void smp_local_timer_interrupt(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | #endif |
| 39 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #define TICK_SIZE (tick_nsec / 1000) |
| 41 | |
| 42 | /* |
| 43 | * Change this if you have some constant time drift |
| 44 | */ |
| 45 | |
| 46 | /* This is for machines which generate the exact clock. */ |
| 47 | #define USECS_PER_JIFFY (1000000/HZ) |
| 48 | |
| 49 | static unsigned long latch; |
| 50 | |
| 51 | static unsigned long do_gettimeoffset(void) |
| 52 | { |
| 53 | unsigned long elapsed_time = 0; /* [us] */ |
| 54 | |
| 55 | #if defined(CONFIG_CHIP_M32102) || defined(CONFIG_CHIP_XNUX2) \ |
| 56 | || defined(CONFIG_CHIP_VDEC2) || defined(CONFIG_CHIP_M32700) \ |
Hirokazu Takata | 9287d95 | 2006-01-06 00:18:41 -0800 | [diff] [blame] | 57 | || defined(CONFIG_CHIP_OPSP) || defined(CONFIG_CHIP_M32104) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | #ifndef CONFIG_SMP |
| 59 | |
| 60 | unsigned long count; |
| 61 | |
| 62 | /* timer count may underflow right here */ |
| 63 | count = inl(M32R_MFT2CUT_PORTL); |
| 64 | |
| 65 | if (inl(M32R_ICU_CR18_PORTL) & 0x00000100) /* underflow check */ |
| 66 | count = 0; |
| 67 | |
| 68 | count = (latch - count) * TICK_SIZE; |
| 69 | elapsed_time = (count + latch / 2) / latch; |
| 70 | /* NOTE: LATCH is equal to the "interval" value (= reload count). */ |
| 71 | |
| 72 | #else /* CONFIG_SMP */ |
| 73 | unsigned long count; |
| 74 | static unsigned long p_jiffies = -1; |
| 75 | static unsigned long p_count = 0; |
| 76 | |
| 77 | /* timer count may underflow right here */ |
| 78 | count = inl(M32R_MFT2CUT_PORTL); |
| 79 | |
| 80 | if (jiffies == p_jiffies && count > p_count) |
| 81 | count = 0; |
| 82 | |
| 83 | p_jiffies = jiffies; |
| 84 | p_count = count; |
| 85 | |
| 86 | count = (latch - count) * TICK_SIZE; |
| 87 | elapsed_time = (count + latch / 2) / latch; |
| 88 | /* NOTE: LATCH is equal to the "interval" value (= reload count). */ |
| 89 | #endif /* CONFIG_SMP */ |
| 90 | #elif defined(CONFIG_CHIP_M32310) |
| 91 | #warning do_gettimeoffse not implemented |
| 92 | #else |
| 93 | #error no chip configuration |
| 94 | #endif |
| 95 | |
| 96 | return elapsed_time; |
| 97 | } |
| 98 | |
| 99 | /* |
| 100 | * This version of gettimeofday has near microsecond resolution. |
| 101 | */ |
| 102 | void do_gettimeofday(struct timeval *tv) |
| 103 | { |
| 104 | unsigned long seq; |
| 105 | unsigned long usec, sec; |
| 106 | unsigned long max_ntp_tick = tick_usec - tickadj; |
| 107 | |
| 108 | do { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | seq = read_seqbegin(&xtime_lock); |
| 110 | |
| 111 | usec = do_gettimeoffset(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | |
| 113 | /* |
| 114 | * If time_adjust is negative then NTP is slowing the clock |
| 115 | * so make sure not to go into next possible interval. |
| 116 | * Better to lose some accuracy than have time go backwards.. |
| 117 | */ |
Atsushi Nemoto | 8ef3860 | 2006-09-30 23:28:31 -0700 | [diff] [blame] | 118 | if (unlikely(time_adjust < 0)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | usec = min(usec, max_ntp_tick); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | |
| 121 | sec = xtime.tv_sec; |
| 122 | usec += (xtime.tv_nsec / 1000); |
| 123 | } while (read_seqretry(&xtime_lock, seq)); |
| 124 | |
| 125 | while (usec >= 1000000) { |
| 126 | usec -= 1000000; |
| 127 | sec++; |
| 128 | } |
| 129 | |
| 130 | tv->tv_sec = sec; |
| 131 | tv->tv_usec = usec; |
| 132 | } |
| 133 | |
| 134 | EXPORT_SYMBOL(do_gettimeofday); |
| 135 | |
| 136 | int do_settimeofday(struct timespec *tv) |
| 137 | { |
| 138 | time_t wtm_sec, sec = tv->tv_sec; |
| 139 | long wtm_nsec, nsec = tv->tv_nsec; |
| 140 | |
| 141 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) |
| 142 | return -EINVAL; |
| 143 | |
| 144 | write_seqlock_irq(&xtime_lock); |
| 145 | /* |
| 146 | * This is revolting. We need to set "xtime" correctly. However, the |
| 147 | * value in this location is the value at the most recent update of |
| 148 | * wall time. Discover what correction gettimeofday() would have |
| 149 | * made, and then undo it! |
| 150 | */ |
| 151 | nsec -= do_gettimeoffset() * NSEC_PER_USEC; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | |
| 153 | wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); |
| 154 | wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); |
| 155 | |
| 156 | set_normalized_timespec(&xtime, sec, nsec); |
| 157 | set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); |
| 158 | |
john stultz | b149ee2 | 2005-09-06 15:17:46 -0700 | [diff] [blame] | 159 | ntp_clear(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 160 | write_sequnlock_irq(&xtime_lock); |
| 161 | clock_was_set(); |
| 162 | |
| 163 | return 0; |
| 164 | } |
| 165 | |
| 166 | EXPORT_SYMBOL(do_settimeofday); |
| 167 | |
| 168 | /* |
| 169 | * In order to set the CMOS clock precisely, set_rtc_mmss has to be |
| 170 | * called 500 ms after the second nowtime has started, because when |
| 171 | * nowtime is written into the registers of the CMOS clock, it will |
| 172 | * jump to the next second precisely 500 ms later. Check the Motorola |
| 173 | * MC146818A or Dallas DS12887 data sheet for details. |
| 174 | * |
| 175 | * BUG: This routine does not handle hour overflow properly; it just |
| 176 | * sets the minutes. Usually you won't notice until after reboot! |
| 177 | */ |
| 178 | static inline int set_rtc_mmss(unsigned long nowtime) |
| 179 | { |
| 180 | return 0; |
| 181 | } |
| 182 | |
| 183 | /* last time the cmos clock got updated */ |
| 184 | static long last_rtc_update = 0; |
| 185 | |
| 186 | /* |
| 187 | * timer_interrupt() needs to keep up the real-time clock, |
| 188 | * as well as call the "do_timer()" routine every clocktick |
| 189 | */ |
Adrian Bunk | 81e4807 | 2008-09-24 15:01:47 +0900 | [diff] [blame] | 190 | static irqreturn_t timer_interrupt(int irq, void *dev_id) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | { |
| 192 | #ifndef CONFIG_SMP |
Al Viro | 9c8e7f5 | 2006-10-07 16:29:18 +0100 | [diff] [blame] | 193 | profile_tick(CPU_PROFILING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | #endif |
Atsushi Nemoto | 3171a03 | 2006-09-29 02:00:32 -0700 | [diff] [blame] | 195 | do_timer(1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | |
| 197 | #ifndef CONFIG_SMP |
Al Viro | 9c8e7f5 | 2006-10-07 16:29:18 +0100 | [diff] [blame] | 198 | update_process_times(user_mode(get_irq_regs())); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | #endif |
| 200 | /* |
| 201 | * If we have an externally synchronized Linux clock, then update |
| 202 | * CMOS clock accordingly every ~11 minutes. Set_rtc_mmss() has to be |
| 203 | * called as close as possible to 500 ms before the new second starts. |
| 204 | */ |
Hirokazu Takata | 2757a71 | 2005-08-01 21:11:35 -0700 | [diff] [blame] | 205 | write_seqlock(&xtime_lock); |
john stultz | b149ee2 | 2005-09-06 15:17:46 -0700 | [diff] [blame] | 206 | if (ntp_synced() |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | && xtime.tv_sec > last_rtc_update + 660 |
| 208 | && (xtime.tv_nsec / 1000) >= 500000 - ((unsigned)TICK_SIZE) / 2 |
| 209 | && (xtime.tv_nsec / 1000) <= 500000 + ((unsigned)TICK_SIZE) / 2) |
| 210 | { |
| 211 | if (set_rtc_mmss(xtime.tv_sec) == 0) |
| 212 | last_rtc_update = xtime.tv_sec; |
| 213 | else /* do it again in 60 s */ |
| 214 | last_rtc_update = xtime.tv_sec - 600; |
| 215 | } |
Hirokazu Takata | 2757a71 | 2005-08-01 21:11:35 -0700 | [diff] [blame] | 216 | write_sequnlock(&xtime_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | /* As we return to user mode fire off the other CPU schedulers.. |
| 218 | this is basically because we don't yet share IRQ's around. |
| 219 | This message is rigged to be safe on the 386 - basically it's |
| 220 | a hack, so don't look closely for now.. */ |
| 221 | |
| 222 | #ifdef CONFIG_SMP |
Al Viro | 9c8e7f5 | 2006-10-07 16:29:18 +0100 | [diff] [blame] | 223 | smp_local_timer_interrupt(); |
Hirokazu Takata | 2757a71 | 2005-08-01 21:11:35 -0700 | [diff] [blame] | 224 | smp_send_timer(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | |
| 227 | return IRQ_HANDLED; |
| 228 | } |
| 229 | |
Adrian Bunk | 81e4807 | 2008-09-24 15:01:47 +0900 | [diff] [blame] | 230 | static struct irqaction irq0 = { |
Thomas Gleixner | 977676a | 2007-10-16 01:26:36 -0700 | [diff] [blame] | 231 | .handler = timer_interrupt, |
| 232 | .flags = IRQF_DISABLED, |
Thomas Gleixner | 977676a | 2007-10-16 01:26:36 -0700 | [diff] [blame] | 233 | .name = "MFT2", |
| 234 | }; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | |
| 236 | void __init time_init(void) |
| 237 | { |
| 238 | unsigned int epoch, year, mon, day, hour, min, sec; |
| 239 | |
| 240 | sec = min = hour = day = mon = year = 0; |
| 241 | epoch = 0; |
| 242 | |
| 243 | year = 23; |
| 244 | mon = 4; |
| 245 | day = 17; |
| 246 | |
| 247 | /* Attempt to guess the epoch. This is the same heuristic as in rtc.c |
| 248 | so no stupid things will happen to timekeeping. Who knows, maybe |
| 249 | Ultrix also uses 1952 as epoch ... */ |
| 250 | if (year > 10 && year < 44) |
| 251 | epoch = 1980; |
| 252 | else if (year < 96) |
| 253 | epoch = 1952; |
| 254 | year += epoch; |
| 255 | |
| 256 | xtime.tv_sec = mktime(year, mon, day, hour, min, sec); |
| 257 | xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ); |
| 258 | set_normalized_timespec(&wall_to_monotonic, |
| 259 | -xtime.tv_sec, -xtime.tv_nsec); |
| 260 | |
| 261 | #if defined(CONFIG_CHIP_M32102) || defined(CONFIG_CHIP_XNUX2) \ |
| 262 | || defined(CONFIG_CHIP_VDEC2) || defined(CONFIG_CHIP_M32700) \ |
Hirokazu Takata | 9287d95 | 2006-01-06 00:18:41 -0800 | [diff] [blame] | 263 | || defined(CONFIG_CHIP_OPSP) || defined(CONFIG_CHIP_M32104) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | |
| 265 | /* M32102 MFT setup */ |
| 266 | setup_irq(M32R_IRQ_MFT2, &irq0); |
| 267 | { |
| 268 | unsigned long bus_clock; |
| 269 | unsigned short divide; |
| 270 | |
| 271 | bus_clock = boot_cpu_data.bus_clock; |
| 272 | divide = boot_cpu_data.timer_divide; |
| 273 | latch = (bus_clock/divide + HZ / 2) / HZ; |
| 274 | |
| 275 | printk("Timer start : latch = %ld\n", latch); |
| 276 | |
| 277 | outl((M32R_MFTMOD_CC_MASK | M32R_MFTMOD_TCCR \ |
| 278 | |M32R_MFTMOD_CSSEL011), M32R_MFT2MOD_PORTL); |
| 279 | outl(latch, M32R_MFT2RLD_PORTL); |
| 280 | outl(latch, M32R_MFT2CUT_PORTL); |
| 281 | outl(0, M32R_MFT2CMPRLD_PORTL); |
| 282 | outl((M32R_MFTCR_MFT2MSK|M32R_MFTCR_MFT2EN), M32R_MFTCR_PORTL); |
| 283 | } |
| 284 | |
| 285 | #elif defined(CONFIG_CHIP_M32310) |
| 286 | #warning time_init not implemented |
| 287 | #else |
| 288 | #error no chip configuration |
| 289 | #endif |
| 290 | } |