Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/sh/kernel/rtc.c -- SH3 / SH4 on-chip RTC support |
| 3 | * |
| 4 | * Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org> |
| 5 | * Copyright (C) 1999 Tetsuya Okada & Niibe Yutaka |
| 6 | */ |
| 7 | |
| 8 | #include <linux/init.h> |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/sched.h> |
| 11 | #include <linux/time.h> |
| 12 | |
| 13 | #include <asm/io.h> |
| 14 | #include <asm/rtc.h> |
| 15 | |
| 16 | #ifndef BCD_TO_BIN |
| 17 | #define BCD_TO_BIN(val) ((val)=((val)&15) + ((val)>>4)*10) |
| 18 | #endif |
| 19 | |
| 20 | #ifndef BIN_TO_BCD |
| 21 | #define BIN_TO_BCD(val) ((val)=(((val)/10)<<4) + (val)%10) |
| 22 | #endif |
| 23 | |
| 24 | void sh_rtc_gettimeofday(struct timespec *ts) |
| 25 | { |
| 26 | unsigned int sec128, sec, sec2, min, hr, wk, day, mon, yr, yr100, cf_bit; |
| 27 | unsigned long flags; |
| 28 | |
| 29 | again: |
| 30 | do { |
| 31 | local_irq_save(flags); |
| 32 | ctrl_outb(0, RCR1); /* Clear CF-bit */ |
| 33 | sec128 = ctrl_inb(R64CNT); |
| 34 | sec = ctrl_inb(RSECCNT); |
| 35 | min = ctrl_inb(RMINCNT); |
| 36 | hr = ctrl_inb(RHRCNT); |
| 37 | wk = ctrl_inb(RWKCNT); |
| 38 | day = ctrl_inb(RDAYCNT); |
| 39 | mon = ctrl_inb(RMONCNT); |
| 40 | #if defined(CONFIG_CPU_SH4) |
| 41 | yr = ctrl_inw(RYRCNT); |
| 42 | yr100 = (yr >> 8); |
| 43 | yr &= 0xff; |
| 44 | #else |
| 45 | yr = ctrl_inb(RYRCNT); |
| 46 | yr100 = (yr == 0x99) ? 0x19 : 0x20; |
| 47 | #endif |
| 48 | sec2 = ctrl_inb(R64CNT); |
| 49 | cf_bit = ctrl_inb(RCR1) & RCR1_CF; |
| 50 | local_irq_restore(flags); |
| 51 | } while (cf_bit != 0 || ((sec128 ^ sec2) & RTC_BIT_INVERTED) != 0); |
| 52 | |
| 53 | BCD_TO_BIN(yr100); |
| 54 | BCD_TO_BIN(yr); |
| 55 | BCD_TO_BIN(mon); |
| 56 | BCD_TO_BIN(day); |
| 57 | BCD_TO_BIN(hr); |
| 58 | BCD_TO_BIN(min); |
| 59 | BCD_TO_BIN(sec); |
| 60 | |
| 61 | if (yr > 99 || mon < 1 || mon > 12 || day > 31 || day < 1 || |
| 62 | hr > 23 || min > 59 || sec > 59) { |
| 63 | printk(KERN_ERR |
| 64 | "SH RTC: invalid value, resetting to 1 Jan 2000\n"); |
| 65 | local_irq_save(flags); |
| 66 | ctrl_outb(RCR2_RESET, RCR2); /* Reset & Stop */ |
| 67 | ctrl_outb(0, RSECCNT); |
| 68 | ctrl_outb(0, RMINCNT); |
| 69 | ctrl_outb(0, RHRCNT); |
| 70 | ctrl_outb(6, RWKCNT); |
| 71 | ctrl_outb(1, RDAYCNT); |
| 72 | ctrl_outb(1, RMONCNT); |
| 73 | #if defined(CONFIG_CPU_SH4) |
| 74 | ctrl_outw(0x2000, RYRCNT); |
| 75 | #else |
| 76 | ctrl_outb(0, RYRCNT); |
| 77 | #endif |
| 78 | ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start */ |
| 79 | goto again; |
| 80 | } |
| 81 | |
| 82 | #if RTC_BIT_INVERTED != 0 |
| 83 | if ((sec128 & RTC_BIT_INVERTED)) |
| 84 | sec--; |
| 85 | #endif |
| 86 | |
| 87 | ts->tv_sec = mktime(yr100 * 100 + yr, mon, day, hr, min, sec); |
| 88 | ts->tv_nsec = ((sec128 * 1000000) / 128) * 1000; |
| 89 | } |
| 90 | |
| 91 | /* |
| 92 | * Changed to only care about tv_sec, and not the full timespec struct |
| 93 | * (i.e. tv_nsec). It can easily be switched to timespec for future cpus |
| 94 | * that support setting usec or nsec RTC values. |
| 95 | */ |
| 96 | int sh_rtc_settimeofday(const time_t secs) |
| 97 | { |
| 98 | int retval = 0; |
| 99 | int real_seconds, real_minutes, cmos_minutes; |
| 100 | unsigned long flags; |
| 101 | |
| 102 | local_irq_save(flags); |
| 103 | ctrl_outb(RCR2_RESET, RCR2); /* Reset pre-scaler & stop RTC */ |
| 104 | |
| 105 | cmos_minutes = ctrl_inb(RMINCNT); |
| 106 | BCD_TO_BIN(cmos_minutes); |
| 107 | |
| 108 | /* |
| 109 | * since we're only adjusting minutes and seconds, |
| 110 | * don't interfere with hour overflow. This avoids |
| 111 | * messing with unknown time zones but requires your |
| 112 | * RTC not to be off by more than 15 minutes |
| 113 | */ |
| 114 | real_seconds = secs % 60; |
| 115 | real_minutes = secs / 60; |
| 116 | if (((abs(real_minutes - cmos_minutes) + 15)/30) & 1) |
| 117 | real_minutes += 30; /* correct for half hour time zone */ |
| 118 | real_minutes %= 60; |
| 119 | |
| 120 | if (abs(real_minutes - cmos_minutes) < 30) { |
| 121 | BIN_TO_BCD(real_seconds); |
| 122 | BIN_TO_BCD(real_minutes); |
| 123 | ctrl_outb(real_seconds, RSECCNT); |
| 124 | ctrl_outb(real_minutes, RMINCNT); |
| 125 | } else { |
| 126 | printk(KERN_WARNING |
| 127 | "set_rtc_time: can't update from %d to %d\n", |
| 128 | cmos_minutes, real_minutes); |
| 129 | retval = -1; |
| 130 | } |
| 131 | |
| 132 | ctrl_outb(RCR2_RTCEN|RCR2_START, RCR2); /* Start RTC */ |
| 133 | local_irq_restore(flags); |
| 134 | |
| 135 | return retval; |
| 136 | } |