diff options
Diffstat (limited to 'arch/sh/kernel/cpu/rtc.c')
| -rw-r--r-- | arch/sh/kernel/cpu/rtc.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/rtc.c b/arch/sh/kernel/cpu/rtc.c new file mode 100644 index 00000000000..f8361f5e788 --- /dev/null +++ b/arch/sh/kernel/cpu/rtc.c @@ -0,0 +1,136 @@ +/* + * linux/arch/sh/kernel/rtc.c -- SH3 / SH4 on-chip RTC support + * + * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> + * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/time.h> + +#include <asm/io.h> +#include <asm/rtc.h> + +#ifndef BCD_TO_BIN +#define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10) +#endif + +#ifndef BIN_TO_BCD +#define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10) +#endif + +void sh_rtc_gettimeofday(struct timespec *ts) +{ + unsigned int sec128, sec, sec2, min, hr, wk, day, mon, yr, yr100, cf_bit; + unsigned long flags; + + again: + do { + local_irq_save(flags); + ctrl_outb(0, RCR1); /* Clear CF-bit */ + sec128 = ctrl_inb(R64CNT); + sec = ctrl_inb(RSECCNT); + min = ctrl_inb(RMINCNT); + hr = ctrl_inb(RHRCNT); + wk = ctrl_inb(RWKCNT); + day = ctrl_inb(RDAYCNT); + mon = ctrl_inb(RMONCNT); +#if defined(CONFIG_CPU_SH4) + yr = ctrl_inw(RYRCNT); + yr100 = (yr >> 8); + yr &= 0xff; +#else + yr = ctrl_inb(RYRCNT); + yr100 = (yr == 0x99) ? 0x19 : 0x20; +#endif + sec2 = ctrl_inb(R64CNT); + cf_bit = ctrl_inb(RCR1) & RCR1_CF; + local_irq_restore(flags); + } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0); + + BCD_TO_BIN(yr100); + BCD_TO_BIN(yr); + BCD_TO_BIN(mon); + BCD_TO_BIN(day); + BCD_TO_BIN(hr); + BCD_TO_BIN(min); + BCD_TO_BIN(sec); + + if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 || + hr > 23 || min > 59 || sec > 59) { + printk(KERN_ERR + "SH RTC: invalid value, resetting to 1 Jan 2000\n"); + local_irq_save(flags); + ctrl_outb(RCR2_RESET, RCR2); /* Reset & Stop */ + ctrl_outb(0, RSECCNT); + ctrl_outb(0, RMINCNT); + ctrl_outb(0, RHRCNT); + ctrl_outb(6, RWKCNT); + ctrl_outb(1, RDAYCNT); + ctrl_outb(1, RMONCNT); +#if defined(CONFIG_CPU_SH4) + ctrl_outw(0x2000, RYRCNT); +#else + ctrl_outb(0, RYRCNT); +#endif + ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start */ + goto again; + } + +#if RTC_BIT_INVERTED != 0 + if ((sec128 & RTC_BIT_INVERTED)) + sec--; +#endif + + ts->tv_sec = mktime(yr100 * 100 + yr, mon, day, hr, min, sec); + ts->tv_nsec = ((sec128 * 1000000) / 128) * 1000; +} + +/* + * Changed to only care about tv_sec, and not the full timespec struct + * (i.e. tv_nsec). It can easily be switched to timespec for future cpus + * that support setting usec or nsec RTC values. + */ +int sh_rtc_settimeofday(const time_t secs) +{ + int retval = 0; + int real_seconds, real_minutes, cmos_minutes; + unsigned long flags; + + local_irq_save(flags); + ctrl_outb(RCR2_RESET, RCR2); /* Reset pre-scaler & stop RTC */ + + cmos_minutes = ctrl_inb(RMINCNT); + BCD_TO_BIN(cmos_minutes); + + /* + * since we're only adjusting minutes and seconds, + * don't interfere with hour overflow. This avoids + * messing with unknown time zones but requires your + * RTC not to be off by more than 15 minutes + */ + real_seconds = secs % 60; + real_minutes = secs / 60; + if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1) + real_minutes += 30; /* correct for half hour time zone */ + real_minutes %= 60; + + if (abs(real_minutes - cmos_minutes) < 30) { + BIN_TO_BCD(real_seconds); + BIN_TO_BCD(real_minutes); + ctrl_outb(real_seconds, RSECCNT); + ctrl_outb(real_minutes, RMINCNT); + } else { + printk(KERN_WARNING + "set_rtc_time: can't update from %d to %d\n", + cmos_minutes, real_minutes); + retval = -1; + } + + ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start RTC */ + local_irq_restore(flags); + + return retval; +} |