[thirdparty/u-boot.git] / drivers / rtc / ds174x.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2001
 * ARIO Data Networks, Inc. dchiu@ariodata.com
 *
 * Based on MontaVista DS1743 code and U-Boot mc146818 code
 */

/*
 * Date & Time support for the DS174x RTC
 */

/*#define	DEBUG*/

#include <common.h>
#include <command.h>
#include <rtc.h>

#if defined(CONFIG_CMD_DATE)

static uchar rtc_read( unsigned int addr );
static void  rtc_write( unsigned int addr, uchar val);

#define RTC_BASE		( CONFIG_SYS_NVRAM_SIZE + CONFIG_SYS_NVRAM_BASE_ADDR )

#define RTC_YEAR		( RTC_BASE + 7 )
#define RTC_MONTH		( RTC_BASE + 6 )
#define RTC_DAY_OF_MONTH	( RTC_BASE + 5 )
#define RTC_DAY_OF_WEEK		( RTC_BASE + 4 )
#define RTC_HOURS		( RTC_BASE + 3 )
#define RTC_MINUTES		( RTC_BASE + 2 )
#define RTC_SECONDS		( RTC_BASE + 1 )
#define RTC_CENTURY		( RTC_BASE + 0 )

#define RTC_CONTROLA		RTC_CENTURY
#define RTC_CONTROLB		RTC_SECONDS
#define RTC_CONTROLC		RTC_DAY_OF_WEEK

#define RTC_CA_WRITE		0x80
#define RTC_CA_READ		0x40

#define RTC_CB_OSC_DISABLE	0x80

#define RTC_CC_BATTERY_FLAG	0x80
#define RTC_CC_FREQ_TEST	0x40

/* ------------------------------------------------------------------------- */

int rtc_get( struct rtc_time *tmp )
{
	uchar sec, min, hour;
	uchar mday, wday, mon, year;

	int century;

	uchar reg_a;

	reg_a = rtc_read( RTC_CONTROLA );
	/* lock clock registers for read */
	rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_READ ));

	sec     = rtc_read( RTC_SECONDS );
	min     = rtc_read( RTC_MINUTES );
	hour    = rtc_read( RTC_HOURS );
	mday    = rtc_read( RTC_DAY_OF_MONTH );
	wday    = rtc_read( RTC_DAY_OF_WEEK );
	mon     = rtc_read( RTC_MONTH );
	year    = rtc_read( RTC_YEAR );
	century = rtc_read( RTC_CENTURY );

	/* unlock clock registers after read */
	rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ ));

#ifdef RTC_DEBUG
	printf( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
		"hr: %02x min: %02x sec: %02x\n",
		year, mon_cent, mday, wday,
		hour, min, sec );
#endif
	tmp->tm_sec  = bcd2bin( sec  & 0x7F );
	tmp->tm_min  = bcd2bin( min  & 0x7F );
	tmp->tm_hour = bcd2bin( hour & 0x3F );
	tmp->tm_mday = bcd2bin( mday & 0x3F );
	tmp->tm_mon  = bcd2bin( mon & 0x1F );
	tmp->tm_wday = bcd2bin( wday & 0x07 );

	/* glue year from century and year in century */
	tmp->tm_year = bcd2bin( year ) +
		( bcd2bin( century & 0x3F ) * 100 );

	tmp->tm_yday = 0;
	tmp->tm_isdst= 0;
#ifdef RTC_DEBUG
	printf( "Get DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
		tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
#endif
	return 0;
}

int rtc_set( struct rtc_time *tmp )
{
	uchar reg_a;
#ifdef RTC_DEBUG
	printf( "Set DATE: %4d-%02d-%02d (wday=%d)  TIME: %2d:%02d:%02d\n",
		tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
		tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
#endif
	/* lock clock registers for write */
	reg_a = rtc_read( RTC_CONTROLA );
	rtc_write( RTC_CONTROLA, ( reg_a | RTC_CA_WRITE ));

	rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon ));

	rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday ));
	rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday ));
	rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour ));
	rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min ));
	rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec ));

	/* break year up into century and year in century */
	rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 ));
	rtc_write( RTC_CENTURY, bin2bcd( tmp->tm_year / 100 ));

	/* unlock clock registers after read */
	rtc_write( RTC_CONTROLA, ( reg_a  & ~RTC_CA_WRITE ));

	return 0;
}

void rtc_reset (void)
{
	uchar reg_a, reg_b, reg_c;

	reg_a = rtc_read( RTC_CONTROLA );
	reg_b = rtc_read( RTC_CONTROLB );

	if ( reg_b & RTC_CB_OSC_DISABLE )
	{
		printf( "real-time-clock was stopped. Now starting...\n" );
		reg_a |= RTC_CA_WRITE;
		reg_b &= ~RTC_CB_OSC_DISABLE;

		rtc_write( RTC_CONTROLA, reg_a );
		rtc_write( RTC_CONTROLB, reg_b );
	}

	/* make sure read/write clock register bits are cleared */
	reg_a &= ~( RTC_CA_WRITE | RTC_CA_READ );
	rtc_write( RTC_CONTROLA, reg_a );

	reg_c = rtc_read( RTC_CONTROLC );
	if (( reg_c & RTC_CC_BATTERY_FLAG ) == 0 )
		printf( "RTC battery low. Clock setting may not be reliable.\n" );
}

/* ------------------------------------------------------------------------- */

static uchar rtc_read( unsigned int addr )
{
	uchar val = in8( addr );
#ifdef RTC_DEBUG
	printf( "rtc_read: %x:%x\n", addr, val );
#endif
	return( val );
}

static void rtc_write( unsigned int addr, uchar val )
{
#ifdef RTC_DEBUG
	printf( "rtc_write: %x:%x\n", addr, val );
#endif
	out8( addr, val );
}

#endif
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
5b1d7137 WD	2	/*
	3	* (C) Copyright 2001
	4	* ARIO Data Networks, Inc. dchiu@ariodata.com
	5	*
	6	* Based on MontaVista DS1743 code and U-Boot mc146818 code
5b1d7137 WD	7	*/
	8
	9	/*
	10	* Date & Time support for the DS174x RTC
	11	*/
	12
	13	/#define DEBUG/
	14
	15	#include <common.h>
	16	#include <command.h>
	17	#include <rtc.h>
	18
871c18dd	19	#if defined(CONFIG_CMD_DATE)
5b1d7137 WD	20
	21	static uchar rtc_read( unsigned int addr );
	22	static void rtc_write( unsigned int addr, uchar val);
5b1d7137	23
6d0f6bcf	24	#define RTC_BASE ( CONFIG_SYS_NVRAM_SIZE + CONFIG_SYS_NVRAM_BASE_ADDR )
5b1d7137 WD	25
	26	#define RTC_YEAR ( RTC_BASE + 7 )
	27	#define RTC_MONTH ( RTC_BASE + 6 )
	28	#define RTC_DAY_OF_MONTH ( RTC_BASE + 5 )
	29	#define RTC_DAY_OF_WEEK ( RTC_BASE + 4 )
	30	#define RTC_HOURS ( RTC_BASE + 3 )
	31	#define RTC_MINUTES ( RTC_BASE + 2 )
	32	#define RTC_SECONDS ( RTC_BASE + 1 )
	33	#define RTC_CENTURY ( RTC_BASE + 0 )
	34
	35	#define RTC_CONTROLA RTC_CENTURY
	36	#define RTC_CONTROLB RTC_SECONDS
	37	#define RTC_CONTROLC RTC_DAY_OF_WEEK
	38
	39	#define RTC_CA_WRITE 0x80
	40	#define RTC_CA_READ 0x40
	41
	42	#define RTC_CB_OSC_DISABLE 0x80
	43
	44	#define RTC_CC_BATTERY_FLAG 0x80
	45	#define RTC_CC_FREQ_TEST 0x40
	46
	47	/* ------------------------------------------------------------------------- */
	48
b73a19e1	49	int rtc_get( struct rtc_time *tmp )
5b1d7137 WD	50	{
	51	uchar sec, min, hour;
	52	uchar mday, wday, mon, year;
	53
	54	int century;
	55
	56	uchar reg_a;
	57
	58	reg_a = rtc_read( RTC_CONTROLA );
	59	/* lock clock registers for read */
	60	rtc_write( RTC_CONTROLA, ( reg_a \| RTC_CA_READ ));
	61
	62	sec = rtc_read( RTC_SECONDS );
	63	min = rtc_read( RTC_MINUTES );
	64	hour = rtc_read( RTC_HOURS );
	65	mday = rtc_read( RTC_DAY_OF_MONTH );
	66	wday = rtc_read( RTC_DAY_OF_WEEK );
	67	mon = rtc_read( RTC_MONTH );
	68	year = rtc_read( RTC_YEAR );
	69	century = rtc_read( RTC_CENTURY );
	70
	71	/* unlock clock registers after read */
	72	rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_READ ));
	73
	74	#ifdef RTC_DEBUG
	75	printf( "Get RTC year: %02x mon/cent: %02x mday: %02x wday: %02x "
	76	"hr: %02x min: %02x sec: %02x\n",
	77	year, mon_cent, mday, wday,
	78	hour, min, sec );
	79	#endif
	80	tmp->tm_sec = bcd2bin( sec & 0x7F );
	81	tmp->tm_min = bcd2bin( min & 0x7F );
	82	tmp->tm_hour = bcd2bin( hour & 0x3F );
	83	tmp->tm_mday = bcd2bin( mday & 0x3F );
	84	tmp->tm_mon = bcd2bin( mon & 0x1F );
	85	tmp->tm_wday = bcd2bin( wday & 0x07 );
	86
	87	/* glue year from century and year in century */
	88	tmp->tm_year = bcd2bin( year ) +
	89	( bcd2bin( century & 0x3F ) * 100 );
	90
	91	tmp->tm_yday = 0;
	92	tmp->tm_isdst= 0;
	93	#ifdef RTC_DEBUG
	94	printf( "Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
	95	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
	96	tmp->tm_hour, tmp->tm_min, tmp->tm_sec );
	97	#endif
53eec6f1	98	return 0;
5b1d7137 WD	99	}
5b1d7137 WD	100
d1e23194	101	int rtc_set( struct rtc_time *tmp )
5b1d7137 WD	102	{
	103	uchar reg_a;
	104	#ifdef RTC_DEBUG
	105	printf( "Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
	106	tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday,
	107	tmp->tm_hour, tmp->tm_min, tmp->tm_sec);
	108	#endif
	109	/* lock clock registers for write */
	110	reg_a = rtc_read( RTC_CONTROLA );
	111	rtc_write( RTC_CONTROLA, ( reg_a \| RTC_CA_WRITE ));
	112
	113	rtc_write( RTC_MONTH, bin2bcd( tmp->tm_mon ));
	114
	115	rtc_write( RTC_DAY_OF_WEEK, bin2bcd( tmp->tm_wday ));
	116	rtc_write( RTC_DAY_OF_MONTH, bin2bcd( tmp->tm_mday ));
	117	rtc_write( RTC_HOURS, bin2bcd( tmp->tm_hour ));
	118	rtc_write( RTC_MINUTES, bin2bcd( tmp->tm_min ));
	119	rtc_write( RTC_SECONDS, bin2bcd( tmp->tm_sec ));
	120
	121	/* break year up into century and year in century */
	122	rtc_write( RTC_YEAR, bin2bcd( tmp->tm_year % 100 ));
	123	rtc_write( RTC_CENTURY, bin2bcd( tmp->tm_year / 100 ));
	124
	125	/* unlock clock registers after read */
	126	rtc_write( RTC_CONTROLA, ( reg_a & ~RTC_CA_WRITE ));
d1e23194 JCPV	127
d1e23194 JCPV	128	return 0;
5b1d7137 WD	129	}
	130
	131	void rtc_reset (void)
	132	{
	133	uchar reg_a, reg_b, reg_c;
	134
	135	reg_a = rtc_read( RTC_CONTROLA );
	136	reg_b = rtc_read( RTC_CONTROLB );
	137
	138	if ( reg_b & RTC_CB_OSC_DISABLE )
	139	{
	140	printf( "real-time-clock was stopped. Now starting...\n" );
	141	reg_a \|= RTC_CA_WRITE;
	142	reg_b &= ~RTC_CB_OSC_DISABLE;
	143
	144	rtc_write( RTC_CONTROLA, reg_a );
	145	rtc_write( RTC_CONTROLB, reg_b );
	146	}
	147
	148	/* make sure read/write clock register bits are cleared */
	149	reg_a &= ~( RTC_CA_WRITE \| RTC_CA_READ );
	150	rtc_write( RTC_CONTROLA, reg_a );
	151
	152	reg_c = rtc_read( RTC_CONTROLC );
	153	if (( reg_c & RTC_CC_BATTERY_FLAG ) == 0 )
	154	printf( "RTC battery low. Clock setting may not be reliable.\n" );
	155	}
	156
	157	/* ------------------------------------------------------------------------- */
	158
	159	static uchar rtc_read( unsigned int addr )
	160	{
	161	uchar val = in8( addr );
	162	#ifdef RTC_DEBUG
	163	printf( "rtc_read: %x:%x\n", addr, val );
	164	#endif
	165	return( val );
	166	}
	167
	168	static void rtc_write( unsigned int addr, uchar val )
	169	{
	170	#ifdef RTC_DEBUG
	171	printf( "rtc_write: %x:%x\n", addr, val );
	172	#endif
	173	out8( addr, val );
	174	}
	175
068b60a0	176	#endif