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