rtc: add support of mx27 rtc

This driver has been tested on board armadeus apf27.

Signed-off-by: Philippe Reynes <tremyfr@yahoo.fr>
Acked-by: Stefano Babic <sbabic@denx.de>

arch/arm/include/asm/arch-mx27/imx-regs.h

@@ -24,6 +24,8 @@
 #ifndef _IMX_REGS_H
 #define _IMX_REGS_H
 
+#include <asm/arch/regs-rtc.h>
+
 #ifndef __ASSEMBLY__
 
 extern void imx_gpio_mode (int gpio_mode);
@@ -224,6 +226,7 @@ struct fuse_bank0_regs {
 #define IMX_TIM1_BASE		(0x03000 + IMX_IO_BASE)
 #define IMX_TIM2_BASE		(0x04000 + IMX_IO_BASE)
 #define IMX_TIM3_BASE		(0x05000 + IMX_IO_BASE)
+#define IMX_RTC_BASE		(0x07000 + IMX_IO_BASE)
 #define UART1_BASE		(0x0a000 + IMX_IO_BASE)
 #define UART2_BASE		(0x0b000 + IMX_IO_BASE)
 #define UART3_BASE		(0x0c000 + IMX_IO_BASE)

arch/arm/include/asm/arch-mx27/regs-rtc.h

@@ -0,0 +1,40 @@
+/*
+ * Freescale i.MX27 RTC Register Definitions
+ *
+ * Copyright (C) 2012 Philippe Reynes <tremyfr@yahoo.fr>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ */
+
+#ifndef __MX27_REGS_RTC_H__
+#define __MX27_REGS_RTC_H__
+
+#ifndef	__ASSEMBLY__
+struct rtc_regs {
+	u32 hourmin;
+	u32 seconds;
+	u32 alrm_hm;
+	u32 alrm_sec;
+	u32 rtcctl;
+	u32 rtcisr;
+	u32 rtcienr;
+	u32 stpwch;
+	u32 dayr;
+	u32 dayalarm;
+};
+#endif /* __ASSEMBLY__*/
+
+#endif	/* __MX28_REGS_RTC_H__ */

drivers/rtc/Makefile

@@ -59,6 +59,7 @@ COBJS-$(CONFIG_RTC_MK48T59) += mk48t59.o
 COBJS-$(CONFIG_RTC_MPC5200) += mpc5xxx.o
 COBJS-$(CONFIG_RTC_MPC8xx) += mpc8xx.o
 COBJS-$(CONFIG_RTC_MV) += mvrtc.o
+COBJS-$(CONFIG_RTC_MX27) += mx27rtc.o
 COBJS-$(CONFIG_RTC_MXS) += mxsrtc.o
 COBJS-$(CONFIG_RTC_PCF8563) += pcf8563.o
 COBJS-$(CONFIG_RTC_PL031) += pl031.o

drivers/rtc/mx27rtc.c

@@ -0,0 +1,83 @@
+/*
+ * Freescale i.MX27 RTC Driver
+ *
+ * Copyright (C) 2012 Philippe Reynes <tremyfr@yahoo.fr>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ */
+
+#include <common.h>
+#include <rtc.h>
+#include <asm/io.h>
+#include <asm/arch/imx-regs.h>
+
+#define HOUR_SHIFT 8
+#define HOUR_MASK  0x1f
+#define MIN_SHIFT  0
+#define MIN_MASK   0x3f
+
+int rtc_get(struct rtc_time *time)
+{
+	struct rtc_regs *rtc_regs = (struct rtc_regs *)IMX_RTC_BASE;
+	uint32_t day, hour, min, sec;
+
+	day  = readl(&rtc_regs->dayr);
+	hour = readl(&rtc_regs->hourmin);
+	sec  = readl(&rtc_regs->seconds);
+
+	min  = (hour >> MIN_SHIFT) & MIN_MASK;
+	hour = (hour >> HOUR_SHIFT) & HOUR_MASK;
+
+	sec += min * 60 + hour * 3600 + day * 24 * 3600;
+
+	to_tm(sec, time);
+
+	return 0;
+}
+
+int rtc_set(struct rtc_time *time)
+{
+	struct rtc_regs *rtc_regs = (struct rtc_regs *)IMX_RTC_BASE;
+	uint32_t day, hour, min, sec;
+
+	sec = mktime(time->tm_year, time->tm_mon, time->tm_mday,
+		time->tm_hour, time->tm_min, time->tm_sec);
+
+	day  = sec / (24 * 3600);
+	sec  = sec % (24 * 3600);
+	hour = sec / 3600;
+	sec  = sec % 3600;
+	min  = sec / 60;
+	sec  = sec % 60;
+
+	hour  = (hour & HOUR_MASK) << HOUR_SHIFT;
+	hour |= (min & MIN_MASK) << MIN_SHIFT;
+
+	writel(day, &rtc_regs->dayr);
+	writel(hour, &rtc_regs->hourmin);
+	writel(sec, &rtc_regs->seconds);
+
+	return 0;
+}
+
+void rtc_reset(void)
+{
+	struct rtc_regs *rtc_regs = (struct rtc_regs *)IMX_RTC_BASE;
+
+	writel(0, &rtc_regs->dayr);
+	writel(0, &rtc_regs->hourmin);
+	writel(0, &rtc_regs->seconds);
+}