1f6d57916SPaul Mackerras /* 2f6d57916SPaul Mackerras * Support for periodic interrupts (100 per second) and for getting 3f6d57916SPaul Mackerras * the current time from the RTC on Power Macintoshes. 4f6d57916SPaul Mackerras * 5f6d57916SPaul Mackerras * We use the decrementer register for our periodic interrupts. 6f6d57916SPaul Mackerras * 7f6d57916SPaul Mackerras * Paul Mackerras August 1996. 8f6d57916SPaul Mackerras * Copyright (C) 1996 Paul Mackerras. 9f6d57916SPaul Mackerras */ 10f6d57916SPaul Mackerras #include <linux/config.h> 11f6d57916SPaul Mackerras #include <linux/errno.h> 12f6d57916SPaul Mackerras #include <linux/sched.h> 13f6d57916SPaul Mackerras #include <linux/kernel.h> 14f6d57916SPaul Mackerras #include <linux/param.h> 15f6d57916SPaul Mackerras #include <linux/string.h> 16f6d57916SPaul Mackerras #include <linux/mm.h> 17f6d57916SPaul Mackerras #include <linux/init.h> 18f6d57916SPaul Mackerras #include <linux/time.h> 19f6d57916SPaul Mackerras #include <linux/adb.h> 20f6d57916SPaul Mackerras #include <linux/cuda.h> 21f6d57916SPaul Mackerras #include <linux/pmu.h> 22f6d57916SPaul Mackerras #include <linux/hardirq.h> 23f6d57916SPaul Mackerras 24f6d57916SPaul Mackerras #include <asm/sections.h> 25f6d57916SPaul Mackerras #include <asm/prom.h> 26f6d57916SPaul Mackerras #include <asm/system.h> 27f6d57916SPaul Mackerras #include <asm/io.h> 28f6d57916SPaul Mackerras #include <asm/pgtable.h> 29f6d57916SPaul Mackerras #include <asm/machdep.h> 30f6d57916SPaul Mackerras #include <asm/time.h> 31f6d57916SPaul Mackerras #include <asm/nvram.h> 32f6d57916SPaul Mackerras 33f6d57916SPaul Mackerras /* Apparently the RTC stores seconds since 1 Jan 1904 */ 34f6d57916SPaul Mackerras #define RTC_OFFSET 2082844800 35f6d57916SPaul Mackerras 36f6d57916SPaul Mackerras /* 37f6d57916SPaul Mackerras * Calibrate the decrementer frequency with the VIA timer 1. 38f6d57916SPaul Mackerras */ 39f6d57916SPaul Mackerras #define VIA_TIMER_FREQ_6 4700000 /* time 1 frequency * 6 */ 40f6d57916SPaul Mackerras 41f6d57916SPaul Mackerras /* VIA registers */ 42f6d57916SPaul Mackerras #define RS 0x200 /* skip between registers */ 43f6d57916SPaul Mackerras #define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */ 44f6d57916SPaul Mackerras #define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */ 45f6d57916SPaul Mackerras #define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */ 46f6d57916SPaul Mackerras #define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */ 47f6d57916SPaul Mackerras #define ACR (11*RS) /* Auxiliary control register */ 48f6d57916SPaul Mackerras #define IFR (13*RS) /* Interrupt flag register */ 49f6d57916SPaul Mackerras 50f6d57916SPaul Mackerras /* Bits in ACR */ 51f6d57916SPaul Mackerras #define T1MODE 0xc0 /* Timer 1 mode */ 52f6d57916SPaul Mackerras #define T1MODE_CONT 0x40 /* continuous interrupts */ 53f6d57916SPaul Mackerras 54f6d57916SPaul Mackerras /* Bits in IFR and IER */ 55f6d57916SPaul Mackerras #define T1_INT 0x40 /* Timer 1 interrupt */ 56f6d57916SPaul Mackerras 57f6d57916SPaul Mackerras extern struct timezone sys_tz; 58f6d57916SPaul Mackerras 59f6d57916SPaul Mackerras long __init 60f6d57916SPaul Mackerras pmac_time_init(void) 61f6d57916SPaul Mackerras { 62f6d57916SPaul Mackerras #ifdef CONFIG_NVRAM 63f6d57916SPaul Mackerras s32 delta = 0; 64f6d57916SPaul Mackerras int dst; 65f6d57916SPaul Mackerras 66f6d57916SPaul Mackerras delta = ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x9)) << 16; 67f6d57916SPaul Mackerras delta |= ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xa)) << 8; 68f6d57916SPaul Mackerras delta |= pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xb); 69f6d57916SPaul Mackerras if (delta & 0x00800000UL) 70f6d57916SPaul Mackerras delta |= 0xFF000000UL; 71f6d57916SPaul Mackerras dst = ((pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x8) & 0x80) != 0); 72f6d57916SPaul Mackerras printk("GMT Delta read from XPRAM: %d minutes, DST: %s\n", delta/60, 73f6d57916SPaul Mackerras dst ? "on" : "off"); 74f6d57916SPaul Mackerras return delta; 75f6d57916SPaul Mackerras #else 76f6d57916SPaul Mackerras return 0; 77f6d57916SPaul Mackerras #endif 78f6d57916SPaul Mackerras } 79f6d57916SPaul Mackerras 80143a1decSPaul Mackerras unsigned long pmac_get_boot_time(void) 81f6d57916SPaul Mackerras { 82f6d57916SPaul Mackerras #if defined(CONFIG_ADB_CUDA) || defined(CONFIG_ADB_PMU) 83f6d57916SPaul Mackerras struct adb_request req; 84f6d57916SPaul Mackerras unsigned long now; 85f6d57916SPaul Mackerras #endif 86f6d57916SPaul Mackerras 87f6d57916SPaul Mackerras /* Get the time from the RTC */ 88f6d57916SPaul Mackerras switch (sys_ctrler) { 89f6d57916SPaul Mackerras #ifdef CONFIG_ADB_CUDA 90f6d57916SPaul Mackerras case SYS_CTRLER_CUDA: 91f6d57916SPaul Mackerras if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0) 92f6d57916SPaul Mackerras return 0; 93f6d57916SPaul Mackerras while (!req.complete) 94f6d57916SPaul Mackerras cuda_poll(); 95f6d57916SPaul Mackerras if (req.reply_len != 7) 96f6d57916SPaul Mackerras printk(KERN_ERR "pmac_get_rtc_time: got %d byte reply\n", 97f6d57916SPaul Mackerras req.reply_len); 98f6d57916SPaul Mackerras now = (req.reply[3] << 24) + (req.reply[4] << 16) 99f6d57916SPaul Mackerras + (req.reply[5] << 8) + req.reply[6]; 100f6d57916SPaul Mackerras return now - RTC_OFFSET; 101f6d57916SPaul Mackerras #endif /* CONFIG_ADB_CUDA */ 102f6d57916SPaul Mackerras #ifdef CONFIG_ADB_PMU 103f6d57916SPaul Mackerras case SYS_CTRLER_PMU: 104f6d57916SPaul Mackerras if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0) 105f6d57916SPaul Mackerras return 0; 106f6d57916SPaul Mackerras while (!req.complete) 107f6d57916SPaul Mackerras pmu_poll(); 108f6d57916SPaul Mackerras if (req.reply_len != 4) 109f6d57916SPaul Mackerras printk(KERN_ERR "pmac_get_rtc_time: got %d byte reply\n", 110f6d57916SPaul Mackerras req.reply_len); 111f6d57916SPaul Mackerras now = (req.reply[0] << 24) + (req.reply[1] << 16) 112f6d57916SPaul Mackerras + (req.reply[2] << 8) + req.reply[3]; 113f6d57916SPaul Mackerras return now - RTC_OFFSET; 114f6d57916SPaul Mackerras #endif /* CONFIG_ADB_PMU */ 115f6d57916SPaul Mackerras default: ; 116f6d57916SPaul Mackerras } 117f6d57916SPaul Mackerras return 0; 118f6d57916SPaul Mackerras } 119f6d57916SPaul Mackerras 120143a1decSPaul Mackerras void pmac_get_rtc_time(struct rtc_time *tm) 121f6d57916SPaul Mackerras { 122143a1decSPaul Mackerras unsigned long now; 123143a1decSPaul Mackerras 124143a1decSPaul Mackerras now = pmac_get_boot_time(); 125143a1decSPaul Mackerras to_tm(now, tm); 126143a1decSPaul Mackerras tm->tm_year -= 1900; 127143a1decSPaul Mackerras tm->tm_mon -= 1; /* month is 0-based */ 128143a1decSPaul Mackerras } 129143a1decSPaul Mackerras 130143a1decSPaul Mackerras int pmac_set_rtc_time(struct rtc_time *tm) 131143a1decSPaul Mackerras { 132143a1decSPaul Mackerras unsigned long nowtime; 133f6d57916SPaul Mackerras #if defined(CONFIG_ADB_CUDA) || defined(CONFIG_ADB_PMU) 134f6d57916SPaul Mackerras struct adb_request req; 135f6d57916SPaul Mackerras #endif 136f6d57916SPaul Mackerras 137143a1decSPaul Mackerras nowtime = mktime(tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday, 138143a1decSPaul Mackerras tm->tm_hour, tm->tm_min, tm->tm_sec); 139f6d57916SPaul Mackerras nowtime += RTC_OFFSET; 140f6d57916SPaul Mackerras 141f6d57916SPaul Mackerras switch (sys_ctrler) { 142f6d57916SPaul Mackerras #ifdef CONFIG_ADB_CUDA 143f6d57916SPaul Mackerras case SYS_CTRLER_CUDA: 144f6d57916SPaul Mackerras if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME, 145143a1decSPaul Mackerras nowtime >> 24, nowtime >> 16, nowtime >> 8, 146143a1decSPaul Mackerras nowtime) < 0) 147f6d57916SPaul Mackerras return 0; 148f6d57916SPaul Mackerras while (!req.complete) 149f6d57916SPaul Mackerras cuda_poll(); 150f6d57916SPaul Mackerras if ((req.reply_len != 3) && (req.reply_len != 7)) 151f6d57916SPaul Mackerras printk(KERN_ERR "pmac_set_rtc_time: got %d byte reply\n", 152f6d57916SPaul Mackerras req.reply_len); 153f6d57916SPaul Mackerras return 1; 154f6d57916SPaul Mackerras #endif /* CONFIG_ADB_CUDA */ 155f6d57916SPaul Mackerras #ifdef CONFIG_ADB_PMU 156f6d57916SPaul Mackerras case SYS_CTRLER_PMU: 157f6d57916SPaul Mackerras if (pmu_request(&req, NULL, 5, PMU_SET_RTC, 158f6d57916SPaul Mackerras nowtime >> 24, nowtime >> 16, nowtime >> 8, nowtime) < 0) 159f6d57916SPaul Mackerras return 0; 160f6d57916SPaul Mackerras while (!req.complete) 161f6d57916SPaul Mackerras pmu_poll(); 162f6d57916SPaul Mackerras if (req.reply_len != 0) 163f6d57916SPaul Mackerras printk(KERN_ERR "pmac_set_rtc_time: got %d byte reply\n", 164f6d57916SPaul Mackerras req.reply_len); 165f6d57916SPaul Mackerras return 1; 166f6d57916SPaul Mackerras #endif /* CONFIG_ADB_PMU */ 167f6d57916SPaul Mackerras default: 168f6d57916SPaul Mackerras return 0; 169f6d57916SPaul Mackerras } 170f6d57916SPaul Mackerras } 171f6d57916SPaul Mackerras 172f6d57916SPaul Mackerras /* 173f6d57916SPaul Mackerras * Calibrate the decrementer register using VIA timer 1. 174f6d57916SPaul Mackerras * This is used both on powermacs and CHRP machines. 175f6d57916SPaul Mackerras */ 176f6d57916SPaul Mackerras int __init 177f6d57916SPaul Mackerras via_calibrate_decr(void) 178f6d57916SPaul Mackerras { 179f6d57916SPaul Mackerras struct device_node *vias; 180f6d57916SPaul Mackerras volatile unsigned char __iomem *via; 181f6d57916SPaul Mackerras int count = VIA_TIMER_FREQ_6 / 100; 182f6d57916SPaul Mackerras unsigned int dstart, dend; 183f6d57916SPaul Mackerras 184f6d57916SPaul Mackerras vias = find_devices("via-cuda"); 185f6d57916SPaul Mackerras if (vias == 0) 186f6d57916SPaul Mackerras vias = find_devices("via-pmu"); 187f6d57916SPaul Mackerras if (vias == 0) 188f6d57916SPaul Mackerras vias = find_devices("via"); 189f6d57916SPaul Mackerras if (vias == 0 || vias->n_addrs == 0) 190f6d57916SPaul Mackerras return 0; 191f6d57916SPaul Mackerras via = ioremap(vias->addrs[0].address, vias->addrs[0].size); 192f6d57916SPaul Mackerras 193f6d57916SPaul Mackerras /* set timer 1 for continuous interrupts */ 194f6d57916SPaul Mackerras out_8(&via[ACR], (via[ACR] & ~T1MODE) | T1MODE_CONT); 195f6d57916SPaul Mackerras /* set the counter to a small value */ 196f6d57916SPaul Mackerras out_8(&via[T1CH], 2); 197f6d57916SPaul Mackerras /* set the latch to `count' */ 198f6d57916SPaul Mackerras out_8(&via[T1LL], count); 199f6d57916SPaul Mackerras out_8(&via[T1LH], count >> 8); 200f6d57916SPaul Mackerras /* wait until it hits 0 */ 201f6d57916SPaul Mackerras while ((in_8(&via[IFR]) & T1_INT) == 0) 202f6d57916SPaul Mackerras ; 203f6d57916SPaul Mackerras dstart = get_dec(); 204f6d57916SPaul Mackerras /* clear the interrupt & wait until it hits 0 again */ 205f6d57916SPaul Mackerras in_8(&via[T1CL]); 206f6d57916SPaul Mackerras while ((in_8(&via[IFR]) & T1_INT) == 0) 207f6d57916SPaul Mackerras ; 208f6d57916SPaul Mackerras dend = get_dec(); 209f6d57916SPaul Mackerras 2105629d41dSPaul Mackerras tb_ticks_per_jiffy = (dstart - dend) / ((6 * HZ)/100); 211f6d57916SPaul Mackerras tb_to_us = mulhwu_scale_factor(dstart - dend, 60000); 212f6d57916SPaul Mackerras 213f6d57916SPaul Mackerras printk(KERN_INFO "via_calibrate_decr: ticks per jiffy = %u (%u ticks)\n", 214f6d57916SPaul Mackerras tb_ticks_per_jiffy, dstart - dend); 215f6d57916SPaul Mackerras 216f6d57916SPaul Mackerras iounmap(via); 217f6d57916SPaul Mackerras 218f6d57916SPaul Mackerras return 1; 219f6d57916SPaul Mackerras } 220f6d57916SPaul Mackerras 221f6d57916SPaul Mackerras #ifdef CONFIG_PM 222f6d57916SPaul Mackerras /* 223f6d57916SPaul Mackerras * Reset the time after a sleep. 224f6d57916SPaul Mackerras */ 225f6d57916SPaul Mackerras static int 226f6d57916SPaul Mackerras time_sleep_notify(struct pmu_sleep_notifier *self, int when) 227f6d57916SPaul Mackerras { 228f6d57916SPaul Mackerras static unsigned long time_diff; 229f6d57916SPaul Mackerras unsigned long flags; 230f6d57916SPaul Mackerras unsigned long seq; 231f6d57916SPaul Mackerras 232f6d57916SPaul Mackerras switch (when) { 233f6d57916SPaul Mackerras case PBOOK_SLEEP_NOW: 234f6d57916SPaul Mackerras do { 235f6d57916SPaul Mackerras seq = read_seqbegin_irqsave(&xtime_lock, flags); 236143a1decSPaul Mackerras time_diff = xtime.tv_sec - pmac_get_boot_time(); 237f6d57916SPaul Mackerras } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); 238f6d57916SPaul Mackerras break; 239f6d57916SPaul Mackerras case PBOOK_WAKE: 240f6d57916SPaul Mackerras write_seqlock_irqsave(&xtime_lock, flags); 241f6d57916SPaul Mackerras xtime.tv_sec = pmac_get_rtc_time() + time_diff; 242f6d57916SPaul Mackerras xtime.tv_nsec = 0; 243f6d57916SPaul Mackerras last_rtc_update = xtime.tv_sec; 244f6d57916SPaul Mackerras write_sequnlock_irqrestore(&xtime_lock, flags); 245f6d57916SPaul Mackerras break; 246f6d57916SPaul Mackerras } 247f6d57916SPaul Mackerras return PBOOK_SLEEP_OK; 248f6d57916SPaul Mackerras } 249f6d57916SPaul Mackerras 250f6d57916SPaul Mackerras static struct pmu_sleep_notifier time_sleep_notifier = { 251f6d57916SPaul Mackerras time_sleep_notify, SLEEP_LEVEL_MISC, 252f6d57916SPaul Mackerras }; 253f6d57916SPaul Mackerras #endif /* CONFIG_PM */ 254f6d57916SPaul Mackerras 255f6d57916SPaul Mackerras /* 256f6d57916SPaul Mackerras * Query the OF and get the decr frequency. 257f6d57916SPaul Mackerras * This was taken from the pmac time_init() when merging the prep/pmac 258f6d57916SPaul Mackerras * time functions. 259f6d57916SPaul Mackerras */ 260f6d57916SPaul Mackerras void __init 261f6d57916SPaul Mackerras pmac_calibrate_decr(void) 262f6d57916SPaul Mackerras { 263f6d57916SPaul Mackerras struct device_node *cpu; 264f6d57916SPaul Mackerras unsigned int freq, *fp; 265f6d57916SPaul Mackerras 266f6d57916SPaul Mackerras #ifdef CONFIG_PM 267f6d57916SPaul Mackerras pmu_register_sleep_notifier(&time_sleep_notifier); 268f6d57916SPaul Mackerras #endif /* CONFIG_PM */ 269f6d57916SPaul Mackerras 270f6d57916SPaul Mackerras /* We assume MacRISC2 machines have correct device-tree 271f6d57916SPaul Mackerras * calibration. That's better since the VIA itself seems 272f6d57916SPaul Mackerras * to be slightly off. --BenH 273f6d57916SPaul Mackerras */ 274f6d57916SPaul Mackerras if (!machine_is_compatible("MacRISC2") && 275f6d57916SPaul Mackerras !machine_is_compatible("MacRISC3") && 276f6d57916SPaul Mackerras !machine_is_compatible("MacRISC4")) 277f6d57916SPaul Mackerras if (via_calibrate_decr()) 278f6d57916SPaul Mackerras return; 279f6d57916SPaul Mackerras 280f6d57916SPaul Mackerras /* Special case: QuickSilver G4s seem to have a badly calibrated 281f6d57916SPaul Mackerras * timebase-frequency in OF, VIA is much better on these. We should 282f6d57916SPaul Mackerras * probably implement calibration based on the KL timer on these 283f6d57916SPaul Mackerras * machines anyway... -BenH 284f6d57916SPaul Mackerras */ 285f6d57916SPaul Mackerras if (machine_is_compatible("PowerMac3,5")) 286f6d57916SPaul Mackerras if (via_calibrate_decr()) 287f6d57916SPaul Mackerras return; 288f6d57916SPaul Mackerras /* 289f6d57916SPaul Mackerras * The cpu node should have a timebase-frequency property 290f6d57916SPaul Mackerras * to tell us the rate at which the decrementer counts. 291f6d57916SPaul Mackerras */ 292f6d57916SPaul Mackerras cpu = find_type_devices("cpu"); 293f6d57916SPaul Mackerras if (cpu == 0) 294f6d57916SPaul Mackerras panic("can't find cpu node in time_init"); 295f6d57916SPaul Mackerras fp = (unsigned int *) get_property(cpu, "timebase-frequency", NULL); 296f6d57916SPaul Mackerras if (fp == 0) 297f6d57916SPaul Mackerras panic("can't get cpu timebase frequency"); 298f6d57916SPaul Mackerras freq = *fp; 299f6d57916SPaul Mackerras printk("time_init: decrementer frequency = %u.%.6u MHz\n", 300f6d57916SPaul Mackerras freq/1000000, freq%1000000); 301f6d57916SPaul Mackerras tb_ticks_per_jiffy = freq / HZ; 302f6d57916SPaul Mackerras tb_to_us = mulhwu_scale_factor(freq, 1000000); 303f6d57916SPaul Mackerras } 304