diff options
Diffstat (limited to 'arch/ppc64/kernel/pmac_time.c')
| -rw-r--r-- | arch/ppc64/kernel/pmac_time.c | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/arch/ppc64/kernel/pmac_time.c b/arch/ppc64/kernel/pmac_time.c new file mode 100644 index 000000000000..f24827581dd7 --- /dev/null +++ b/arch/ppc64/kernel/pmac_time.c @@ -0,0 +1,201 @@ +/* + * 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/pmu.h> +#include <linux/interrupt.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 + +extern void setup_default_decr(void); + +extern unsigned long ppc_tb_freq; +extern unsigned long ppc_proc_freq; + +/* 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 */ + +extern struct timezone sys_tz; +extern void to_tm(int tim, struct rtc_time * tm); + +void __pmac pmac_get_rtc_time(struct rtc_time *tm) +{ + switch(sys_ctrler) { +#ifdef CONFIG_ADB_PMU + case SYS_CTRLER_PMU: { + /* TODO: Move that to a function in the PMU driver */ + struct adb_request req; + unsigned int now; + + if (pmu_request(&req, NULL, 1, PMU_READ_RTC) < 0) + return; + pmu_wait_complete(&req); + if (req.reply_len != 4) + printk(KERN_ERR "pmac_get_rtc_time: PMU returned a %d" + " bytes reply\n", req.reply_len); + now = (req.reply[0] << 24) + (req.reply[1] << 16) + + (req.reply[2] << 8) + req.reply[3]; + DBG("get: %u -> %u\n", (int)now, (int)(now - RTC_OFFSET)); + now -= RTC_OFFSET; + + to_tm(now, tm); + tm->tm_year -= 1900; + tm->tm_mon -= 1; + + DBG("-> tm_mday: %d, tm_mon: %d, tm_year: %d, %d:%02d:%02d\n", + tm->tm_mday, tm->tm_mon, tm->tm_year, + tm->tm_hour, tm->tm_min, tm->tm_sec); + break; + } +#endif /* CONFIG_ADB_PMU */ + +#ifdef CONFIG_PMAC_SMU + case SYS_CTRLER_SMU: + smu_get_rtc_time(tm); + break; +#endif /* CONFIG_PMAC_SMU */ + default: + ; + } +} + +int __pmac pmac_set_rtc_time(struct rtc_time *tm) +{ + switch(sys_ctrler) { +#ifdef CONFIG_ADB_PMU + case SYS_CTRLER_PMU: { + /* TODO: Move that to a function in the PMU driver */ + struct adb_request req; + unsigned int nowtime; + + DBG("set: tm_mday: %d, tm_mon: %d, tm_year: %d," + " %d:%02d:%02d\n", + tm->tm_mday, tm->tm_mon, tm->tm_year, + tm->tm_hour, tm->tm_min, tm->tm_sec); + + nowtime = mktime(tm->tm_year + 1900, tm->tm_mon + 1, + tm->tm_mday, tm->tm_hour, tm->tm_min, + tm->tm_sec); + + DBG("-> %u -> %u\n", (int)nowtime, + (int)(nowtime + RTC_OFFSET)); + nowtime += 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 "pmac_set_rtc_time: PMU returned a %d" + " bytes reply\n", req.reply_len); + return 0; + } +#endif /* CONFIG_ADB_PMU */ + +#ifdef CONFIG_PMAC_SMU + case SYS_CTRLER_SMU: + return smu_set_rtc_time(tm); +#endif /* CONFIG_PMAC_SMU */ + default: + return -ENODEV; + } +} + +void __init pmac_get_boot_time(struct rtc_time *tm) +{ + pmac_get_rtc_time(tm); + +#ifdef disabled__CONFIG_NVRAM + s32 delta = 0; + 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 +} + +/* + * Query the OF and get the decr frequency. + * This was taken from the pmac time_init() when merging the prep/pmac + * time functions. + */ +void __init pmac_calibrate_decr(void) +{ + struct device_node *cpu; + unsigned int freq, *fp; + struct div_result divres; + + /* + * The cpu node should have a timebase-frequency property + * to tell us the rate at which the decrementer counts. + */ + cpu = find_type_devices("cpu"); + if (cpu == 0) + panic("can't find cpu node in time_init"); + fp = (unsigned int *) get_property(cpu, "timebase-frequency", NULL); + if (fp == 0) + panic("can't get cpu timebase frequency"); + freq = *fp; + printk("time_init: decrementer frequency = %u.%.6u MHz\n", + freq/1000000, freq%1000000); + tb_ticks_per_jiffy = freq / HZ; + tb_ticks_per_sec = tb_ticks_per_jiffy * HZ; + tb_ticks_per_usec = freq / 1000000; + tb_to_us = mulhwu_scale_factor(freq, 1000000); + div128_by_32( 1024*1024, 0, tb_ticks_per_sec, &divres ); + tb_to_xs = divres.result_low; + ppc_tb_freq = freq; + + fp = (unsigned int *)get_property(cpu, "clock-frequency", NULL); + if (fp == 0) + panic("can't get cpu processor frequency"); + ppc_proc_freq = *fp; + + setup_default_decr(); +} + |