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 __be32 __y_m_d; 41 __be64 __h_m_s_ms; 42 long rc = OPAL_BUSY; 43 44 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 45 rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms); 46 if (rc == OPAL_BUSY_EVENT) 47 opal_poll_events(NULL); 48 else 49 mdelay(10); 50 } 51 if (rc != OPAL_SUCCESS) 52 return 0; 53 y_m_d = be32_to_cpu(__y_m_d); 54 h_m_s_ms = be64_to_cpu(__h_m_s_ms); 55 opal_to_tm(y_m_d, h_m_s_ms, &tm); 56 return mktime(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 57 tm.tm_hour, tm.tm_min, tm.tm_sec); 58 } 59 60 void opal_get_rtc_time(struct rtc_time *tm) 61 { 62 long rc = OPAL_BUSY; 63 u32 y_m_d; 64 u64 h_m_s_ms; 65 __be32 __y_m_d; 66 __be64 __h_m_s_ms; 67 68 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 69 rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms); 70 if (rc == OPAL_BUSY_EVENT) 71 opal_poll_events(NULL); 72 else 73 mdelay(10); 74 } 75 if (rc != OPAL_SUCCESS) 76 return; 77 y_m_d = be32_to_cpu(__y_m_d); 78 h_m_s_ms = be64_to_cpu(__h_m_s_ms); 79 opal_to_tm(y_m_d, h_m_s_ms, tm); 80 } 81 82 int opal_set_rtc_time(struct rtc_time *tm) 83 { 84 long rc = OPAL_BUSY; 85 u32 y_m_d = 0; 86 u64 h_m_s_ms = 0; 87 88 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24; 89 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16; 90 y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8; 91 y_m_d |= ((u32)bin2bcd(tm->tm_mday)); 92 93 h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56; 94 h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48; 95 h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40; 96 97 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 98 rc = opal_rtc_write(y_m_d, h_m_s_ms); 99 if (rc == OPAL_BUSY_EVENT) 100 opal_poll_events(NULL); 101 else 102 mdelay(10); 103 } 104 return rc == OPAL_SUCCESS ? 0 : -EIO; 105 } 106