Benjamin Herrenschmidt | 628daa8 | 2011-09-19 17:45:01 +0000 | [diff] [blame] | 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 | } |