| 1 | /* |
| 2 | * linux/arch/m68k/coldfire/time.c |
| 3 | * |
| 4 | * This file contains the coldfire specific time handling pieces. |
| 5 | * |
| 6 | * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved. |
| 7 | * Kurt Mahan <kmahan@freescale.com> |
| 8 | * Jason Jin Jason.Jin@freescale.com |
| 9 | * Shrek Wu B16972@freescale.com |
| 10 | * |
| 11 | * based on linux/arch/m68k/kernel/time.c |
| 12 | */ |
| 13 | #include <linux/clk.h> |
| 14 | #include <linux/clk.h> |
| 15 | #include <linux/clocksource.h> |
| 16 | #include <linux/clockchips.h> |
| 17 | #include <linux/time.h> |
| 18 | #include <linux/timex.h> |
| 19 | #include <linux/errno.h> |
| 20 | #include <linux/module.h> |
| 21 | #include <linux/sysdev.h> |
| 22 | #include <linux/sched.h> |
| 23 | #include <linux/kernel.h> |
| 24 | #include <linux/param.h> |
| 25 | #include <linux/string.h> |
| 26 | #include <linux/mm.h> |
| 27 | #include <linux/rtc.h> |
| 28 | |
| 29 | #include <asm/machdep.h> |
| 30 | #include <linux/io.h> |
| 31 | #include <asm/irq_regs.h> |
| 32 | |
| 33 | #include <linux/profile.h> |
| 34 | #include <asm/mcfsim.h> |
| 35 | #ifdef CONFIG_GENERIC_CLOCKEVENTS |
| 36 | /*extern unsigned long long sys_dtim0_read(void); |
| 37 | extern void sys_dtim_init(void);*/ |
| 38 | extern unsigned long long sys_dtim2_read(void); |
| 39 | extern void sys_dtim2_init(void); |
| 40 | static int cfv4_set_next_event(unsigned long evt, |
| 41 | struct clock_event_device *dev); |
| 42 | static void cfv4_set_mode(enum clock_event_mode mode, |
| 43 | struct clock_event_device *dev); |
| 44 | #if defined(CONFIG_M5445X) |
| 45 | #define FREQ (MCF_BUSCLK / 16) |
| 46 | #else |
| 47 | #define FREQ (MCF_BUSCLK) |
| 48 | #endif |
| 49 | /* |
| 50 | * realtime clock dummy code |
| 51 | */ |
| 52 | |
| 53 | static unsigned long null_rtc_get_time(void) |
| 54 | { |
| 55 | return mktime(2008, 1, 1, 0, 0, 0); |
| 56 | } |
| 57 | |
| 58 | static int null_rtc_set_time(unsigned long sec) |
| 59 | { |
| 60 | return 0; |
| 61 | } |
| 62 | |
| 63 | static unsigned long (*cf_rtc_get_time)(void) = null_rtc_get_time; |
| 64 | static int (*cf_rtc_set_time)(unsigned long) = null_rtc_set_time; |
| 65 | #endif /* CONFIG_GENERIC_CLOCKEVENTS */ |
| 66 | |
| 67 | /* |
| 68 | * old pre-GENERIC clock code |
| 69 | */ |
| 70 | |
| 71 | #ifndef CONFIG_GENERIC_CLOCKEVENTS |
| 72 | /* |
| 73 | * timer_interrupt() needs to keep up the real-time clock, |
| 74 | * as well as call the "do_timer()" routine every clocktick |
| 75 | */ |
| 76 | static irqreturn_t timer_interrupt(int irq, void *dummy) |
| 77 | { |
| 78 | #ifdef CONFIG_COLDFIRE |
| 79 | /* kick hardware timer if necessary */ |
| 80 | if (mach_tick) |
| 81 | mach_tick(); |
| 82 | #endif |
| 83 | do_timer(1); |
| 84 | #ifndef CONFIG_SMP |
| 85 | update_process_times(user_mode(get_irq_regs())); |
| 86 | #endif |
| 87 | profile_tick(CPU_PROFILING); |
| 88 | |
| 89 | #ifdef CONFIG_HEARTBEAT |
| 90 | /* use power LED as a heartbeat instead -- much more useful |
| 91 | for debugging -- based on the version for PReP by Cort */ |
| 92 | /* acts like an actual heart beat -- ie thump-thump-pause... */ |
| 93 | if (mach_heartbeat) { |
| 94 | unsigned cnt = 0, period = 0, dist = 0; |
| 95 | |
| 96 | if (cnt == 0 || cnt == dist) |
| 97 | mach_heartbeat(1); |
| 98 | else if (cnt == 7 || cnt == dist+7) |
| 99 | mach_heartbeat(0); |
| 100 | |
| 101 | if (++cnt > period) { |
| 102 | cnt = 0; |
| 103 | /* The hyperbolic function below modifies |
| 104 | * the heartbeat period length in dependency |
| 105 | * of the current (5min) load. It goes through |
| 106 | * the points f(0)=126, f(1)=86, f(5)=51, |
| 107 | * f(inf)->30. */ |
| 108 | period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) |
| 109 | + 30; |
| 110 | dist = period / 4; |
| 111 | } |
| 112 | } |
| 113 | #endif /* CONFIG_HEARTBEAT */ |
| 114 | return IRQ_HANDLED; |
| 115 | } |
| 116 | |
| 117 | void __init time_init(void) |
| 118 | { |
| 119 | struct rtc_time time; |
| 120 | |
| 121 | if (mach_hwclk) { |
| 122 | mach_hwclk(0, &time); |
| 123 | time.tm_year += 1900; |
| 124 | if (time.tm_year < 1970) |
| 125 | time.tm_year += 100; |
| 126 | xtime.tv_sec = mktime(time.tm_year, time.tm_mon, time.tm_mday, |
| 127 | time.tm_hour, time.tm_min, time.tm_sec); |
| 128 | xtime.tv_nsec = 0; |
| 129 | } |
| 130 | wall_to_monotonic.tv_sec = -xtime.tv_sec; |
| 131 | |
| 132 | mach_sched_init(timer_interrupt); |
| 133 | } |
| 134 | #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ |
| 135 | |
| 136 | #ifndef CONFIG_GENERIC_TIME |
| 137 | /* |
| 138 | * This version of gettimeofday has near microsecond resolution. |
| 139 | */ |
| 140 | void do_gettimeofday(struct timeval *tv) |
| 141 | { |
| 142 | unsigned long flags; |
| 143 | unsigned long seq; |
| 144 | unsigned long usec, sec; |
| 145 | unsigned long max_ntp_tick = tick_usec - tickadj; |
| 146 | |
| 147 | do { |
| 148 | seq = read_seqbegin_irqsave(&xtime_lock, flags); |
| 149 | |
| 150 | usec = mach_gettimeoffset(); |
| 151 | |
| 152 | /* |
| 153 | * If time_adjust is negative then NTP is slowing the clock |
| 154 | * so make sure not to go into next possible interval. |
| 155 | * Better to lose some accuracy than have time go backwards.. |
| 156 | */ |
| 157 | if (unlikely(time_adjust < 0)) |
| 158 | usec = min(usec, max_ntp_tick); |
| 159 | |
| 160 | sec = xtime.tv_sec; |
| 161 | usec += xtime.tv_nsec/1000; |
| 162 | } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); |
| 163 | |
| 164 | |
| 165 | while (usec >= 1000000) { |
| 166 | usec -= 1000000; |
| 167 | sec++; |
| 168 | } |
| 169 | |
| 170 | tv->tv_sec = sec; |
| 171 | tv->tv_usec = usec; |
| 172 | } |
| 173 | EXPORT_SYMBOL(do_gettimeofday); |
| 174 | |
| 175 | int do_settimeofday(struct timespec *tv) |
| 176 | { |
| 177 | time_t wtm_sec, sec = tv->tv_sec; |
| 178 | long wtm_nsec, nsec = tv->tv_nsec; |
| 179 | |
| 180 | if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC) |
| 181 | return -EINVAL; |
| 182 | |
| 183 | write_seqlock_irq(&xtime_lock); |
| 184 | /* This is revolting. We need to set the xtime.tv_nsec |
| 185 | * correctly. However, the value in this location is |
| 186 | * is value at the last tick. |
| 187 | * Discover what correction gettimeofday |
| 188 | * would have done, and then undo it! |
| 189 | */ |
| 190 | nsec -= 1000 * mach_gettimeoffset(); |
| 191 | |
| 192 | wtm_sec = wall_to_monotonic.tv_sec + (xtime.tv_sec - sec); |
| 193 | wtm_nsec = wall_to_monotonic.tv_nsec + (xtime.tv_nsec - nsec); |
| 194 | |
| 195 | set_normalized_timespec(&xtime, sec, nsec); |
| 196 | set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); |
| 197 | |
| 198 | ntp_clear(); |
| 199 | write_sequnlock_irq(&xtime_lock); |
| 200 | clock_was_set(); |
| 201 | return 0; |
| 202 | } |
| 203 | EXPORT_SYMBOL(do_settimeofday); |
| 204 | #endif /* !CONFIG_GENERIC_TIME */ |
| 205 | |
| 206 | #ifdef CONFIG_GENERIC_CLOCKEVENTS |
| 207 | /* |
| 208 | * Clock Evnt setup |
| 209 | */ |
| 210 | static struct clock_event_device clockevent_cfv4 = { |
| 211 | .name = "CFV4 timer2even", |
| 212 | .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, |
| 213 | .rating = 200, |
| 214 | .shift = 20, |
| 215 | .set_mode = cfv4_set_mode, |
| 216 | .set_next_event = cfv4_set_next_event, |
| 217 | }; |
| 218 | |
| 219 | static int cfv4_set_next_event(unsigned long evt, |
| 220 | struct clock_event_device *dev) |
| 221 | { |
| 222 | return 0; |
| 223 | } |
| 224 | |
| 225 | static void cfv4_set_mode(enum clock_event_mode mode, |
| 226 | struct clock_event_device *dev) |
| 227 | { |
| 228 | if (mode != CLOCK_EVT_MODE_ONESHOT) |
| 229 | cfv4_set_next_event((FREQ / HZ), dev); |
| 230 | } |
| 231 | |
| 232 | static int __init cfv4_clockevent_init(void) |
| 233 | { |
| 234 | clockevent_cfv4.mult = |
| 235 | div_sc(FREQ, NSEC_PER_SEC, |
| 236 | clockevent_cfv4.shift); |
| 237 | clockevent_cfv4.max_delta_ns = |
| 238 | clockevent_delta2ns((FREQ / HZ), |
| 239 | &clockevent_cfv4); |
| 240 | clockevent_cfv4.min_delta_ns = |
| 241 | clockevent_delta2ns(1, &clockevent_cfv4); |
| 242 | |
| 243 | clockevent_cfv4.cpumask = &cpumask_of_cpu(0); |
| 244 | |
| 245 | printk(KERN_INFO "timer: register clockevent\n"); |
| 246 | clockevents_register_device(&clockevent_cfv4); |
| 247 | |
| 248 | return 0; |
| 249 | } |
| 250 | |
| 251 | /* |
| 252 | * clocksource setup |
| 253 | */ |
| 254 | |
| 255 | struct clocksource clocksource_cfv4 = { |
| 256 | .name = "ColdfireV4", |
| 257 | .rating = 250, |
| 258 | .mask = CLOCKSOURCE_MASK(32), |
| 259 | .read = sys_dtim2_read, |
| 260 | .shift = 20, |
| 261 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, |
| 262 | }; |
| 263 | |
| 264 | /* |
| 265 | * Initialize time subsystem. Called from linux/init/main.c |
| 266 | */ |
| 267 | void __init time_init(void) |
| 268 | { |
| 269 | int ret; |
| 270 | |
| 271 | printk(KERN_INFO "Initializing time\n"); |
| 272 | #if 0 |
| 273 | /* initialize system clocks */ |
| 274 | clk_init(); |
| 275 | #endif |
| 276 | cfv4_clockevent_init(); |
| 277 | /* initialize the system timer */ |
| 278 | /*sys_dtim_init();*/ |
| 279 | sys_dtim2_init(); |
| 280 | /* setup initial system time */ |
| 281 | xtime.tv_sec = cf_rtc_get_time(); |
| 282 | xtime.tv_nsec = 0; |
| 283 | set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, |
| 284 | -xtime.tv_nsec); |
| 285 | |
| 286 | /* JKM */ |
| 287 | clocksource_cfv4.mult = clocksource_hz2mult(FREQ, |
| 288 | clocksource_cfv4.shift); |
| 289 | |
| 290 | /* register our clocksource */ |
| 291 | ret = clocksource_register(&clocksource_cfv4); |
| 292 | if (ret) |
| 293 | printk(KERN_ERR "timer: unable to " |
| 294 | "register clocksource - %d\n", ret); |
| 295 | } |
| 296 | |
| 297 | /* |
| 298 | * sysfs pieces |
| 299 | */ |
| 300 | |
| 301 | static struct sysdev_class timer_class = { |
| 302 | .name = "timer", |
| 303 | }; |
| 304 | |
| 305 | static struct sys_device timer_device = { |
| 306 | .id = 0, |
| 307 | .cls = &timer_class, |
| 308 | }; |
| 309 | |
| 310 | static int __init timer_init_sysfs(void) |
| 311 | { |
| 312 | int err = sysdev_class_register(&timer_class); |
| 313 | if (!err) |
| 314 | err = sysdev_register(&timer_device); |
| 315 | return err; |
| 316 | } |
| 317 | device_initcall(timer_init_sysfs); |
| 318 | #endif /* CONFIG_GENERIC_CLOCKEVENTS */ |
| 319 | |
