| /* |
| * Support for periodic interrupts (100 per second) and for getting |
| * the current time from the RTC on Power Macintoshes. |
| * |
| * We use the decrementer register for our periodic interrupts. |
| * |
| * Paul Mackerras August 1996. |
| * Copyright (C) 1996 Paul Mackerras. |
| * Copyright (C) 2003-2005 Benjamin Herrenschmidt. |
| * |
| */ |
| #include <linux/config.h> |
| #include <linux/errno.h> |
| #include <linux/sched.h> |
| #include <linux/kernel.h> |
| #include <linux/param.h> |
| #include <linux/string.h> |
| #include <linux/mm.h> |
| #include <linux/init.h> |
| #include <linux/time.h> |
| #include <linux/adb.h> |
| #include <linux/cuda.h> |
| #include <linux/pmu.h> |
| #include <linux/interrupt.h> |
| #include <linux/hardirq.h> |
| #include <linux/rtc.h> |
| |
| #include <asm/sections.h> |
| #include <asm/prom.h> |
| #include <asm/system.h> |
| #include <asm/io.h> |
| #include <asm/pgtable.h> |
| #include <asm/machdep.h> |
| #include <asm/time.h> |
| #include <asm/nvram.h> |
| #include <asm/smu.h> |
| |
| #undef DEBUG |
| |
| #ifdef DEBUG |
| #define DBG(x...) printk(x) |
| #else |
| #define DBG(x...) |
| #endif |
| |
| /* Apparently the RTC stores seconds since 1 Jan 1904 */ |
| #define RTC_OFFSET 2082844800 |
| |
| /* |
| * Calibrate the decrementer frequency with the VIA timer 1. |
| */ |
| #define VIA_TIMER_FREQ_6 4700000 /* time 1 frequency * 6 */ |
| |
| /* VIA registers */ |
| #define RS 0x200 /* skip between registers */ |
| #define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */ |
| #define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */ |
| #define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */ |
| #define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */ |
| #define ACR (11*RS) /* Auxiliary control register */ |
| #define IFR (13*RS) /* Interrupt flag register */ |
| |
| /* Bits in ACR */ |
| #define T1MODE 0xc0 /* Timer 1 mode */ |
| #define T1MODE_CONT 0x40 /* continuous interrupts */ |
| |
| /* Bits in IFR and IER */ |
| #define T1_INT 0x40 /* Timer 1 interrupt */ |
| |
| long __init pmac_time_init(void) |
| { |
| s32 delta = 0; |
| #ifdef CONFIG_NVRAM |
| int dst; |
| |
| delta = ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x9)) << 16; |
| delta |= ((s32)pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xa)) << 8; |
| delta |= pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0xb); |
| if (delta & 0x00800000UL) |
| delta |= 0xFF000000UL; |
| dst = ((pmac_xpram_read(PMAC_XPRAM_MACHINE_LOC + 0x8) & 0x80) != 0); |
| printk("GMT Delta read from XPRAM: %d minutes, DST: %s\n", delta/60, |
| dst ? "on" : "off"); |
| #endif |
| return delta; |
| } |
| |
| static void to_rtc_time(unsigned long now, struct rtc_time *tm) |
| { |
| to_tm(now, tm); |
| tm->tm_year -= 1900; |
| tm->tm_mon -= 1; |
| } |
| |
| static unsigned long from_rtc_time(struct rtc_time *tm) |
| { |
| return mktime(tm->tm_year+1900, tm->tm_mon+1, tm->tm_mday, |
| tm->tm_hour, tm->tm_min, tm->tm_sec); |
| } |
| |
| #ifdef CONFIG_ADB_CUDA |
| static unsigned long cuda_get_time(void) |
| { |
| struct adb_request req; |
| unsigned long now; |
| |
| if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0) |
| return 0; |
| while (!req.complete) |
| cuda_poll(); |
| if (req.reply_len != 7) |
| printk(KERN_ERR "cuda_get_time: got %d byte reply\n", |
| req.reply_len); |
| now = (req.reply[3] << 24) + (req.reply[4] << 16) |
| + (req.reply[5] << 8) + req.reply[6]; |
| return now - RTC_OFFSET; |
| } |
| |
| #define cuda_get_rtc_time(tm) to_rtc_time(cuda_get_time(), (tm)) |
| |
| static int cuda_set_rtc_time(struct rtc_time *tm) |
| { |
| unsigned int nowtime; |
| struct adb_request req; |
| |
| nowtime = from_rtc_time(tm) + RTC_OFFSET; |
| if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME, |
| nowtime >> 24, nowtime >> 16, nowtime >> 8, |
| nowtime) < 0) |
| return -ENXIO; |
| while (!req.complete) |
| cuda_poll(); |
| if ((req.reply_len != 3) && (req.reply_len != 7)) |
| printk(KERN_ERR "cuda_set_rtc_time: got %d byte reply\n", |
| req.reply_len); |
| return 0; |
| } |
| |
| #else |
| #define cuda_get_time() 0 |
| #define cuda_get_rtc_time(tm) |
| #define cuda_set_rtc_time(tm) 0 |
| #endif |
| |
| #ifdef CONFIG_ADB_PMU |
| static unsigned long pmu_get_time(void) |
| { |
| struct adb_request req; |
| unsigned long now; |
| |
| if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0) |
| return 0; |
| pmu_wait_complete(&req); |
| if (req.reply_len != 4) |
| printk(KERN_ERR "pmu_get_time: got %d byte reply from PMU\n", |
| req.reply_len); |
| now = (req.reply[0] << 24) + (req.reply[1] << 16) |
| + (req.reply[2] << 8) + req.reply[3]; |
| return now - RTC_OFFSET; |
| } |
| |
| #define pmu_get_rtc_time(tm) to_rtc_time(pmu_get_time(), (tm)) |
| |
| static int pmu_set_rtc_time(struct rtc_time *tm) |
| { |
| unsigned int nowtime; |
| struct adb_request req; |
| |
| nowtime = from_rtc_time(tm) + RTC_OFFSET; |
| if (pmu_request(&req, NULL, 5, PMU_SET_RTC, nowtime >> 24, |
| nowtime >> 16, nowtime >> 8, nowtime) < 0) |
| return -ENXIO; |
| pmu_wait_complete(&req); |
| if (req.reply_len != 0) |
| printk(KERN_ERR "pmu_set_rtc_time: %d byte reply from PMU\n", |
| req.reply_len); |
| return 0; |
| } |
| |
| #else |
| #define pmu_get_time() 0 |
| #define pmu_get_rtc_time(tm) |
| #define pmu_set_rtc_time(tm) 0 |
| #endif |
| |
| #ifdef CONFIG_PMAC_SMU |
| static unsigned long smu_get_time(void) |
| { |
| struct rtc_time tm; |
| |
| if (smu_get_rtc_time(&tm, 1)) |
| return 0; |
| return from_rtc_time(&tm); |
| } |
| |
| #else |
| #define smu_get_time() 0 |
| #define smu_get_rtc_time(tm, spin) |
| #define smu_set_rtc_time(tm, spin) 0 |
| #endif |
| |
| unsigned long pmac_get_boot_time(void) |
| { |
| /* Get the time from the RTC, used only at boot time */ |
| switch (sys_ctrler) { |
| case SYS_CTRLER_CUDA: |
| return cuda_get_time(); |
| case SYS_CTRLER_PMU: |
| return pmu_get_time(); |
| case SYS_CTRLER_SMU: |
| return smu_get_time(); |
| default: |
| return 0; |
| } |
| } |
| |
| void pmac_get_rtc_time(struct rtc_time *tm) |
| { |
| /* Get the time from the RTC, used only at boot time */ |
| switch (sys_ctrler) { |
| case SYS_CTRLER_CUDA: |
| cuda_get_rtc_time(tm); |
| break; |
| case SYS_CTRLER_PMU: |
| pmu_get_rtc_time(tm); |
| break; |
| case SYS_CTRLER_SMU: |
| smu_get_rtc_time(tm, 1); |
| break; |
| default: |
| ; |
| } |
| } |
| |
| int pmac_set_rtc_time(struct rtc_time *tm) |
| { |
| switch (sys_ctrler) { |
| case SYS_CTRLER_CUDA: |
| return cuda_set_rtc_time(tm); |
| case SYS_CTRLER_PMU: |
| return pmu_set_rtc_time(tm); |
| case SYS_CTRLER_SMU: |
| return smu_set_rtc_time(tm, 1); |
| default: |
| return -ENODEV; |
| } |
| } |
| |
| #ifdef CONFIG_PPC32 |
| /* |
| * Calibrate the decrementer register using VIA timer 1. |
| * This is used both on powermacs and CHRP machines. |
| */ |
| int __init via_calibrate_decr(void) |
| { |
| struct device_node *vias; |
| volatile unsigned char __iomem *via; |
| int count = VIA_TIMER_FREQ_6 / 100; |
| unsigned int dstart, dend; |
| |
| vias = find_devices("via-cuda"); |
| if (vias == 0) |
| vias = find_devices("via-pmu"); |
| if (vias == 0) |
| vias = find_devices("via"); |
| if (vias == 0 || vias->n_addrs == 0) |
| return 0; |
| via = ioremap(vias->addrs[0].address, vias->addrs[0].size); |
| |
| /* set timer 1 for continuous interrupts */ |
| out_8(&via[ACR], (via[ACR] & ~T1MODE) | T1MODE_CONT); |
| /* set the counter to a small value */ |
| out_8(&via[T1CH], 2); |
| /* set the latch to `count' */ |
| out_8(&via[T1LL], count); |
| out_8(&via[T1LH], count >> 8); |
| /* wait until it hits 0 */ |
| while ((in_8(&via[IFR]) & T1_INT) == 0) |
| ; |
| dstart = get_dec(); |
| /* clear the interrupt & wait until it hits 0 again */ |
| in_8(&via[T1CL]); |
| while ((in_8(&via[IFR]) & T1_INT) == 0) |
| ; |
| dend = get_dec(); |
| |
| ppc_tb_freq = (dstart - dend) * 100 / 6; |
| |
| iounmap(via); |
| |
| return 1; |
| } |
| #endif |
| |
| #ifdef CONFIG_PM |
| /* |
| * Reset the time after a sleep. |
| */ |
| static int |
| time_sleep_notify(struct pmu_sleep_notifier *self, int when) |
| { |
| static unsigned long time_diff; |
| unsigned long flags; |
| unsigned long seq; |
| struct timespec tv; |
| |
| switch (when) { |
| case PBOOK_SLEEP_NOW: |
| do { |
| seq = read_seqbegin_irqsave(&xtime_lock, flags); |
| time_diff = xtime.tv_sec - pmac_get_boot_time(); |
| } while (read_seqretry_irqrestore(&xtime_lock, seq, flags)); |
| break; |
| case PBOOK_WAKE: |
| tv.tv_sec = pmac_get_boot_time() + time_diff; |
| tv.tv_nsec = 0; |
| do_settimeofday(&tv); |
| break; |
| } |
| return PBOOK_SLEEP_OK; |
| } |
| |
| static struct pmu_sleep_notifier time_sleep_notifier = { |
| time_sleep_notify, SLEEP_LEVEL_MISC, |
| }; |
| #endif /* CONFIG_PM */ |
| |
| /* |
| * Query the OF and get the decr frequency. |
| */ |
| void __init pmac_calibrate_decr(void) |
| { |
| #ifdef CONFIG_PM |
| /* XXX why here? */ |
| pmu_register_sleep_notifier(&time_sleep_notifier); |
| #endif /* CONFIG_PM */ |
| |
| generic_calibrate_decr(); |
| |
| #ifdef CONFIG_PPC32 |
| /* We assume MacRISC2 machines have correct device-tree |
| * calibration. That's better since the VIA itself seems |
| * to be slightly off. --BenH |
| */ |
| if (!machine_is_compatible("MacRISC2") && |
| !machine_is_compatible("MacRISC3") && |
| !machine_is_compatible("MacRISC4")) |
| if (via_calibrate_decr()) |
| return; |
| |
| /* Special case: QuickSilver G4s seem to have a badly calibrated |
| * timebase-frequency in OF, VIA is much better on these. We should |
| * probably implement calibration based on the KL timer on these |
| * machines anyway... -BenH |
| */ |
| if (machine_is_compatible("PowerMac3,5")) |
| if (via_calibrate_decr()) |
| return; |
| #endif |
| } |