1 /* 2 * Freescale i.MX28 RTC Driver 3 * 4 * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com> 5 * on behalf of DENX Software Engineering GmbH 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 * 21 */ 22 23 #include <common.h> 24 #include <rtc.h> 25 #include <asm/io.h> 26 #include <asm/arch/imx-regs.h> 27 #include <asm/arch/sys_proto.h> 28 29 #define MXS_RTC_MAX_TIMEOUT 1000000 30 31 /* Set time in seconds since 1970-01-01 */ 32 int mxs_rtc_set_time(uint32_t secs) 33 { 34 struct mx28_rtc_regs *rtc_regs = (struct mx28_rtc_regs *)MXS_RTC_BASE; 35 int ret; 36 37 writel(secs, &rtc_regs->hw_rtc_seconds); 38 39 /* 40 * The 0x80 here means seconds were copied to analog. This information 41 * is taken from the linux kernel driver for the STMP37xx RTC since 42 * documentation doesn't mention it. 43 */ 44 ret = mx28_wait_mask_clr(&rtc_regs->hw_rtc_stat_reg, 45 0x80 << RTC_STAT_STALE_REGS_OFFSET, MXS_RTC_MAX_TIMEOUT); 46 47 if (ret) 48 printf("MXS RTC: Timeout waiting for update\n"); 49 50 return ret; 51 } 52 53 int rtc_get(struct rtc_time *time) 54 { 55 struct mx28_rtc_regs *rtc_regs = (struct mx28_rtc_regs *)MXS_RTC_BASE; 56 uint32_t secs; 57 58 secs = readl(&rtc_regs->hw_rtc_seconds); 59 to_tm(secs, time); 60 61 return 0; 62 } 63 64 int rtc_set(struct rtc_time *time) 65 { 66 uint32_t secs; 67 68 secs = mktime(time->tm_year, time->tm_mon, time->tm_mday, 69 time->tm_hour, time->tm_min, time->tm_sec); 70 71 return mxs_rtc_set_time(secs); 72 } 73 74 void rtc_reset(void) 75 { 76 struct mx28_rtc_regs *rtc_regs = (struct mx28_rtc_regs *)MXS_RTC_BASE; 77 int ret; 78 79 /* Set time to 1970-01-01 */ 80 mxs_rtc_set_time(0); 81 82 /* Reset the RTC block */ 83 ret = mx28_reset_block(&rtc_regs->hw_rtc_ctrl_reg); 84 if (ret) 85 printf("MXS RTC: Block reset timeout\n"); 86 } 87