1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Freescale i.MX28 RTC Driver 4 * 5 * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com> 6 * on behalf of DENX Software Engineering GmbH 7 */ 8 9 #include <common.h> 10 #include <rtc.h> 11 #include <asm/io.h> 12 #include <asm/arch/imx-regs.h> 13 #include <asm/arch/sys_proto.h> 14 15 #define MXS_RTC_MAX_TIMEOUT 1000000 16 17 /* Set time in seconds since 1970-01-01 */ 18 int mxs_rtc_set_time(uint32_t secs) 19 { 20 struct mxs_rtc_regs *rtc_regs = (struct mxs_rtc_regs *)MXS_RTC_BASE; 21 int ret; 22 23 writel(secs, &rtc_regs->hw_rtc_seconds); 24 25 /* 26 * The 0x80 here means seconds were copied to analog. This information 27 * is taken from the linux kernel driver for the STMP37xx RTC since 28 * documentation doesn't mention it. 29 */ 30 ret = mxs_wait_mask_clr(&rtc_regs->hw_rtc_stat_reg, 31 0x80 << RTC_STAT_STALE_REGS_OFFSET, MXS_RTC_MAX_TIMEOUT); 32 33 if (ret) 34 printf("MXS RTC: Timeout waiting for update\n"); 35 36 return ret; 37 } 38 39 int rtc_get(struct rtc_time *time) 40 { 41 struct mxs_rtc_regs *rtc_regs = (struct mxs_rtc_regs *)MXS_RTC_BASE; 42 uint32_t secs; 43 44 secs = readl(&rtc_regs->hw_rtc_seconds); 45 rtc_to_tm(secs, time); 46 47 return 0; 48 } 49 50 int rtc_set(struct rtc_time *time) 51 { 52 uint32_t secs; 53 54 secs = rtc_mktime(time); 55 56 return mxs_rtc_set_time(secs); 57 } 58 59 void rtc_reset(void) 60 { 61 struct mxs_rtc_regs *rtc_regs = (struct mxs_rtc_regs *)MXS_RTC_BASE; 62 int ret; 63 64 /* Set time to 1970-01-01 */ 65 mxs_rtc_set_time(0); 66 67 /* Reset the RTC block */ 68 ret = mxs_reset_block(&rtc_regs->hw_rtc_ctrl_reg); 69 if (ret) 70 printf("MXS RTC: Block reset timeout\n"); 71 } 72