1 /* 2 * PowerNV Real Time Clock. 3 * 4 * Copyright 2011 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12 13 #include <linux/kernel.h> 14 #include <linux/time.h> 15 #include <linux/bcd.h> 16 #include <linux/rtc.h> 17 #include <linux/delay.h> 18 19 #include <asm/opal.h> 20 #include <asm/firmware.h> 21 22 static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm) 23 { 24 tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) + 25 bcd2bin((y_m_d >> 16) & 0xff)) - 1900; 26 tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1; 27 tm->tm_mday = bcd2bin(y_m_d & 0xff); 28 tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff); 29 tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff); 30 tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff); 31 32 GregorianDay(tm); 33 } 34 35 unsigned long __init opal_get_boot_time(void) 36 { 37 struct rtc_time tm; 38 u32 y_m_d; 39 u64 h_m_s_ms; 40 long rc = OPAL_BUSY; 41 42 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 43 rc = opal_rtc_read(&y_m_d, &h_m_s_ms); 44 if (rc == OPAL_BUSY_EVENT) 45 opal_poll_events(NULL); 46 else 47 mdelay(10); 48 } 49 if (rc != OPAL_SUCCESS) 50 return 0; 51 opal_to_tm(y_m_d, h_m_s_ms, &tm); 52 return mktime(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 53 tm.tm_hour, tm.tm_min, tm.tm_sec); 54 } 55 56 void opal_get_rtc_time(struct rtc_time *tm) 57 { 58 long rc = OPAL_BUSY; 59 u32 y_m_d; 60 u64 h_m_s_ms; 61 62 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 63 rc = opal_rtc_read(&y_m_d, &h_m_s_ms); 64 if (rc == OPAL_BUSY_EVENT) 65 opal_poll_events(NULL); 66 else 67 mdelay(10); 68 } 69 if (rc != OPAL_SUCCESS) 70 return; 71 opal_to_tm(y_m_d, h_m_s_ms, tm); 72 } 73 74 int opal_set_rtc_time(struct rtc_time *tm) 75 { 76 long rc = OPAL_BUSY; 77 u32 y_m_d = 0; 78 u64 h_m_s_ms = 0; 79 80 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24; 81 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16; 82 y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8; 83 y_m_d |= ((u32)bin2bcd(tm->tm_mday)); 84 85 h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56; 86 h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48; 87 h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40; 88 89 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 90 rc = opal_rtc_write(y_m_d, h_m_s_ms); 91 if (rc == OPAL_BUSY_EVENT) 92 opal_poll_events(NULL); 93 else 94 mdelay(10); 95 } 96 return rc == OPAL_SUCCESS ? 0 : -EIO; 97 } 98