1 #include <linux/kernel.h> 2 #include <linux/time.h> 3 #include <linux/timer.h> 4 #include <linux/init.h> 5 #include <linux/rtc.h> 6 #include <linux/delay.h> 7 #include <asm/prom.h> 8 #include <asm/rtas.h> 9 #include <asm/time.h> 10 11 12 #define MAX_RTC_WAIT 5000 /* 5 sec */ 13 #define RTAS_CLOCK_BUSY (-2) 14 unsigned long __init rtas_get_boot_time(void) 15 { 16 int ret[8]; 17 int error; 18 unsigned int wait_time; 19 u64 max_wait_tb; 20 21 max_wait_tb = get_tb() + tb_ticks_per_usec * 1000 * MAX_RTC_WAIT; 22 do { 23 error = rtas_call(rtas_token("get-time-of-day"), 0, 8, ret); 24 25 wait_time = rtas_busy_delay_time(error); 26 if (wait_time) { 27 /* This is boot time so we spin. */ 28 udelay(wait_time*1000); 29 } 30 } while (wait_time && (get_tb() < max_wait_tb)); 31 32 if (error != 0 && printk_ratelimit()) { 33 printk(KERN_WARNING "error: reading the clock failed (%d)\n", 34 error); 35 return 0; 36 } 37 38 return mktime(ret[0], ret[1], ret[2], ret[3], ret[4], ret[5]); 39 } 40 41 /* NOTE: get_rtc_time will get an error if executed in interrupt context 42 * and if a delay is needed to read the clock. In this case we just 43 * silently return without updating rtc_tm. 44 */ 45 void rtas_get_rtc_time(struct rtc_time *rtc_tm) 46 { 47 int ret[8]; 48 int error; 49 unsigned int wait_time; 50 u64 max_wait_tb; 51 52 max_wait_tb = get_tb() + tb_ticks_per_usec * 1000 * MAX_RTC_WAIT; 53 do { 54 error = rtas_call(rtas_token("get-time-of-day"), 0, 8, ret); 55 56 wait_time = rtas_busy_delay_time(error); 57 if (wait_time) { 58 if (in_interrupt() && printk_ratelimit()) { 59 memset(rtc_tm, 0, sizeof(struct rtc_time)); 60 printk(KERN_WARNING "error: reading clock" 61 " would delay interrupt\n"); 62 return; /* delay not allowed */ 63 } 64 msleep(wait_time); 65 } 66 } while (wait_time && (get_tb() < max_wait_tb)); 67 68 if (error != 0 && printk_ratelimit()) { 69 printk(KERN_WARNING "error: reading the clock failed (%d)\n", 70 error); 71 return; 72 } 73 74 rtc_tm->tm_sec = ret[5]; 75 rtc_tm->tm_min = ret[4]; 76 rtc_tm->tm_hour = ret[3]; 77 rtc_tm->tm_mday = ret[2]; 78 rtc_tm->tm_mon = ret[1] - 1; 79 rtc_tm->tm_year = ret[0] - 1900; 80 } 81 82 int rtas_set_rtc_time(struct rtc_time *tm) 83 { 84 int error, wait_time; 85 u64 max_wait_tb; 86 87 max_wait_tb = get_tb() + tb_ticks_per_usec * 1000 * MAX_RTC_WAIT; 88 do { 89 error = rtas_call(rtas_token("set-time-of-day"), 7, 1, NULL, 90 tm->tm_year + 1900, tm->tm_mon + 1, 91 tm->tm_mday, tm->tm_hour, tm->tm_min, 92 tm->tm_sec, 0); 93 94 wait_time = rtas_busy_delay_time(error); 95 if (wait_time) { 96 if (in_interrupt()) 97 return 1; /* probably decrementer */ 98 msleep(wait_time); 99 } 100 } while (wait_time && (get_tb() < max_wait_tb)); 101 102 if (error != 0 && printk_ratelimit()) 103 printk(KERN_WARNING "error: setting the clock failed (%d)\n", 104 error); 105 106 return 0; 107 } 108