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 #include <asm/machdep.h> 22 23 static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm) 24 { 25 tm->tm_year = ((bcd2bin(y_m_d >> 24) * 100) + 26 bcd2bin((y_m_d >> 16) & 0xff)) - 1900; 27 tm->tm_mon = bcd2bin((y_m_d >> 8) & 0xff) - 1; 28 tm->tm_mday = bcd2bin(y_m_d & 0xff); 29 tm->tm_hour = bcd2bin((h_m_s_ms >> 56) & 0xff); 30 tm->tm_min = bcd2bin((h_m_s_ms >> 48) & 0xff); 31 tm->tm_sec = bcd2bin((h_m_s_ms >> 40) & 0xff); 32 33 GregorianDay(tm); 34 } 35 36 unsigned long __init opal_get_boot_time(void) 37 { 38 struct rtc_time tm; 39 u32 y_m_d; 40 u64 h_m_s_ms; 41 __be32 __y_m_d; 42 __be64 __h_m_s_ms; 43 long rc = OPAL_BUSY; 44 45 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 46 rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms); 47 if (rc == OPAL_BUSY_EVENT) 48 opal_poll_events(NULL); 49 else 50 mdelay(10); 51 } 52 if (rc != OPAL_SUCCESS) { 53 ppc_md.get_rtc_time = NULL; 54 ppc_md.set_rtc_time = NULL; 55 return 0; 56 } 57 y_m_d = be32_to_cpu(__y_m_d); 58 h_m_s_ms = be64_to_cpu(__h_m_s_ms); 59 opal_to_tm(y_m_d, h_m_s_ms, &tm); 60 return mktime(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday, 61 tm.tm_hour, tm.tm_min, tm.tm_sec); 62 } 63 64 void opal_get_rtc_time(struct rtc_time *tm) 65 { 66 long rc = OPAL_BUSY; 67 u32 y_m_d; 68 u64 h_m_s_ms; 69 __be32 __y_m_d; 70 __be64 __h_m_s_ms; 71 72 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 73 rc = opal_rtc_read(&__y_m_d, &__h_m_s_ms); 74 if (rc == OPAL_BUSY_EVENT) 75 opal_poll_events(NULL); 76 else 77 mdelay(10); 78 } 79 if (rc != OPAL_SUCCESS) 80 return; 81 y_m_d = be32_to_cpu(__y_m_d); 82 h_m_s_ms = be64_to_cpu(__h_m_s_ms); 83 opal_to_tm(y_m_d, h_m_s_ms, tm); 84 } 85 86 int opal_set_rtc_time(struct rtc_time *tm) 87 { 88 long rc = OPAL_BUSY; 89 u32 y_m_d = 0; 90 u64 h_m_s_ms = 0; 91 92 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) / 100)) << 24; 93 y_m_d |= ((u32)bin2bcd((tm->tm_year + 1900) % 100)) << 16; 94 y_m_d |= ((u32)bin2bcd((tm->tm_mon + 1))) << 8; 95 y_m_d |= ((u32)bin2bcd(tm->tm_mday)); 96 97 h_m_s_ms |= ((u64)bin2bcd(tm->tm_hour)) << 56; 98 h_m_s_ms |= ((u64)bin2bcd(tm->tm_min)) << 48; 99 h_m_s_ms |= ((u64)bin2bcd(tm->tm_sec)) << 40; 100 101 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 102 rc = opal_rtc_write(y_m_d, h_m_s_ms); 103 if (rc == OPAL_BUSY_EVENT) 104 opal_poll_events(NULL); 105 else 106 mdelay(10); 107 } 108 return rc == OPAL_SUCCESS ? 0 : -EIO; 109 } 110