[linux-block.git] / arch / powerpc / platforms / chrp / time.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  Copyright (C) 1991, 1992, 1995  Linus Torvalds
 *
 * Adapted for PowerPC (PReP) by Gary Thomas
 * Modified by Cort Dougan (cort@cs.nmt.edu).
 * Copied and modified from arch/i386/kernel/time.c
 *
 */
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/timex.h>
#include <linux/kernel_stat.h>
#include <linux/mc146818rtc.h>
#include <linux/init.h>
#include <linux/bcd.h>
#include <linux/ioport.h>

#include <asm/io.h>
#include <asm/nvram.h>
#include <asm/prom.h>
#include <asm/sections.h>
#include <asm/time.h>

extern spinlock_t rtc_lock;

#define NVRAM_AS0  0x74
#define NVRAM_AS1  0x75
#define NVRAM_DATA 0x77

static int nvram_as1 = NVRAM_AS1;
static int nvram_as0 = NVRAM_AS0;
static int nvram_data = NVRAM_DATA;

long __init chrp_time_init(void)
{
	struct device_node *rtcs;
	struct resource r;
	int base;

	rtcs = of_find_compatible_node(NULL, "rtc", "pnpPNP,b00");
	if (rtcs == NULL)
		rtcs = of_find_compatible_node(NULL, "rtc", "ds1385-rtc");
	if (rtcs == NULL)
		return 0;
	if (of_address_to_resource(rtcs, 0, &r)) {
		of_node_put(rtcs);
		return 0;
	}
	of_node_put(rtcs);

	base = r.start;
	nvram_as1 = 0;
	nvram_as0 = base;
	nvram_data = base + 1;

	return 0;
}

int chrp_cmos_clock_read(int addr)
{
	if (nvram_as1 != 0)
		outb(addr>>8, nvram_as1);
	outb(addr, nvram_as0);
	return (inb(nvram_data));
}

void chrp_cmos_clock_write(unsigned long val, int addr)
{
	if (nvram_as1 != 0)
		outb(addr>>8, nvram_as1);
	outb(addr, nvram_as0);
	outb(val, nvram_data);
	return;
}

/*
 * Set the hardware clock. -- Cort
 */
int chrp_set_rtc_time(struct rtc_time *tmarg)
{
	unsigned char save_control, save_freq_select;
	struct rtc_time tm = *tmarg;

	spin_lock(&rtc_lock);

	save_control = chrp_cmos_clock_read(RTC_CONTROL); /* tell the clock it's being set */

	chrp_cmos_clock_write((save_control|RTC_SET), RTC_CONTROL);

	save_freq_select = chrp_cmos_clock_read(RTC_FREQ_SELECT); /* stop and reset prescaler */

	chrp_cmos_clock_write((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);

	if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
		tm.tm_sec = bin2bcd(tm.tm_sec);
		tm.tm_min = bin2bcd(tm.tm_min);
		tm.tm_hour = bin2bcd(tm.tm_hour);
		tm.tm_mon = bin2bcd(tm.tm_mon);
		tm.tm_mday = bin2bcd(tm.tm_mday);
		tm.tm_year = bin2bcd(tm.tm_year);
	}
	chrp_cmos_clock_write(tm.tm_sec,RTC_SECONDS);
	chrp_cmos_clock_write(tm.tm_min,RTC_MINUTES);
	chrp_cmos_clock_write(tm.tm_hour,RTC_HOURS);
	chrp_cmos_clock_write(tm.tm_mon,RTC_MONTH);
	chrp_cmos_clock_write(tm.tm_mday,RTC_DAY_OF_MONTH);
	chrp_cmos_clock_write(tm.tm_year,RTC_YEAR);

	/* The following flags have to be released exactly in this order,
	 * otherwise the DS12887 (popular MC146818A clone with integrated
	 * battery and quartz) will not reset the oscillator and will not
	 * update precisely 500 ms later. You won't find this mentioned in
	 * the Dallas Semiconductor data sheets, but who believes data
	 * sheets anyway ...                           -- Markus Kuhn
	 */
	chrp_cmos_clock_write(save_control, RTC_CONTROL);
	chrp_cmos_clock_write(save_freq_select, RTC_FREQ_SELECT);

	spin_unlock(&rtc_lock);
	return 0;
}

void chrp_get_rtc_time(struct rtc_time *tm)
{
	unsigned int year, mon, day, hour, min, sec;

	do {
		sec = chrp_cmos_clock_read(RTC_SECONDS);
		min = chrp_cmos_clock_read(RTC_MINUTES);
		hour = chrp_cmos_clock_read(RTC_HOURS);
		day = chrp_cmos_clock_read(RTC_DAY_OF_MONTH);
		mon = chrp_cmos_clock_read(RTC_MONTH);
		year = chrp_cmos_clock_read(RTC_YEAR);
	} while (sec != chrp_cmos_clock_read(RTC_SECONDS));

	if (!(chrp_cmos_clock_read(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
		sec = bcd2bin(sec);
		min = bcd2bin(min);
		hour = bcd2bin(hour);
		day = bcd2bin(day);
		mon = bcd2bin(mon);
		year = bcd2bin(year);
	}
	if (year < 70)
		year += 100;
	tm->tm_sec = sec;
	tm->tm_min = min;
	tm->tm_hour = hour;
	tm->tm_mday = day;
	tm->tm_mon = mon;
	tm->tm_year = year;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
bbd0abda	2	/*
bbd0abda PM	3	* Copyright (C) 1991, 1992, 1995 Linus Torvalds
	4	*
	5	* Adapted for PowerPC (PReP) by Gary Thomas
	6	* Modified by Cort Dougan (cort@cs.nmt.edu).
	7	* Copied and modified from arch/i386/kernel/time.c
	8	*
	9	*/
	10	#include <linux/errno.h>
	11	#include <linux/sched.h>
	12	#include <linux/kernel.h>
	13	#include <linux/param.h>
	14	#include <linux/string.h>
	15	#include <linux/mm.h>
	16	#include <linux/interrupt.h>
	17	#include <linux/time.h>
	18	#include <linux/timex.h>
	19	#include <linux/kernel_stat.h>
	20	#include <linux/mc146818rtc.h>
	21	#include <linux/init.h>
	22	#include <linux/bcd.h>
575e3216	23	#include <linux/ioport.h>
bbd0abda PM	24
	25	#include <asm/io.h>
	26	#include <asm/nvram.h>
	27	#include <asm/prom.h>
	28	#include <asm/sections.h>
	29	#include <asm/time.h>
	30
	31	extern spinlock_t rtc_lock;
	32
74d51d02 BH	33	#define NVRAM_AS0 0x74
	34	#define NVRAM_AS1 0x75
	35	#define NVRAM_DATA 0x77
	36
bbd0abda PM	37	static int nvram_as1 = NVRAM_AS1;
	38	static int nvram_as0 = NVRAM_AS0;
	39	static int nvram_data = NVRAM_DATA;
	40
	41	long __init chrp_time_init(void)
	42	{
	43	struct device_node *rtcs;
575e3216	44	struct resource r;
bbd0abda PM	45	int base;
bbd0abda PM	46
4bf56e17	47	rtcs = of_find_compatible_node(NULL, "rtc", "pnpPNP,b00");
bbd0abda	48	if (rtcs == NULL)
4bf56e17 SR	49	rtcs = of_find_compatible_node(NULL, "rtc", "ds1385-rtc");
	50	if (rtcs == NULL)
	51	return 0;
	52	if (of_address_to_resource(rtcs, 0, &r)) {
	53	of_node_put(rtcs);
bbd0abda	54	return 0;
4bf56e17 SR	55	}
	56	of_node_put(rtcs);
	57
575e3216	58	base = r.start;
bbd0abda PM	59	nvram_as1 = 0;
	60	nvram_as0 = base;
	61	nvram_data = base + 1;
	62
	63	return 0;
	64	}
	65
	66	int chrp_cmos_clock_read(int addr)
	67	{
	68	if (nvram_as1 != 0)
	69	outb(addr>>8, nvram_as1);
	70	outb(addr, nvram_as0);
	71	return (inb(nvram_data));
	72	}
	73
	74	void chrp_cmos_clock_write(unsigned long val, int addr)
	75	{
	76	if (nvram_as1 != 0)
	77	outb(addr>>8, nvram_as1);
	78	outb(addr, nvram_as0);
	79	outb(val, nvram_data);
	80	return;
	81	}
	82
	83	/*
	84	* Set the hardware clock. -- Cort
	85	*/
	86	int chrp_set_rtc_time(struct rtc_time *tmarg)
	87	{
	88	unsigned char save_control, save_freq_select;
	89	struct rtc_time tm = *tmarg;
	90
	91	spin_lock(&rtc_lock);
	92
	93	save_control = chrp_cmos_clock_read(RTC_CONTROL); /* tell the clock it's being set */
	94
	95	chrp_cmos_clock_write((save_control\|RTC_SET), RTC_CONTROL);
	96
	97	save_freq_select = chrp_cmos_clock_read(RTC_FREQ_SELECT); /* stop and reset prescaler */
	98
	99	chrp_cmos_clock_write((save_freq_select\|RTC_DIV_RESET2), RTC_FREQ_SELECT);
	100
bbd0abda	101	if (!(save_control & RTC_DM_BINARY) \|\| RTC_ALWAYS_BCD) {
8f6ba492 AB	102	tm.tm_sec = bin2bcd(tm.tm_sec);
	103	tm.tm_min = bin2bcd(tm.tm_min);
	104	tm.tm_hour = bin2bcd(tm.tm_hour);
	105	tm.tm_mon = bin2bcd(tm.tm_mon);
	106	tm.tm_mday = bin2bcd(tm.tm_mday);
	107	tm.tm_year = bin2bcd(tm.tm_year);
bbd0abda PM	108	}
	109	chrp_cmos_clock_write(tm.tm_sec,RTC_SECONDS);
	110	chrp_cmos_clock_write(tm.tm_min,RTC_MINUTES);
	111	chrp_cmos_clock_write(tm.tm_hour,RTC_HOURS);
	112	chrp_cmos_clock_write(tm.tm_mon,RTC_MONTH);
	113	chrp_cmos_clock_write(tm.tm_mday,RTC_DAY_OF_MONTH);
	114	chrp_cmos_clock_write(tm.tm_year,RTC_YEAR);
	115
	116	/* The following flags have to be released exactly in this order,
	117	* otherwise the DS12887 (popular MC146818A clone with integrated
	118	* battery and quartz) will not reset the oscillator and will not
	119	* update precisely 500 ms later. You won't find this mentioned in
	120	* the Dallas Semiconductor data sheets, but who believes data
	121	* sheets anyway ... -- Markus Kuhn
	122	*/
	123	chrp_cmos_clock_write(save_control, RTC_CONTROL);
	124	chrp_cmos_clock_write(save_freq_select, RTC_FREQ_SELECT);
	125
	126	spin_unlock(&rtc_lock);
	127	return 0;
	128	}
	129
	130	void chrp_get_rtc_time(struct rtc_time *tm)
	131	{
	132	unsigned int year, mon, day, hour, min, sec;
bbd0abda	133
4dc12ec7	134	do {
bbd0abda PM	135	sec = chrp_cmos_clock_read(RTC_SECONDS);
	136	min = chrp_cmos_clock_read(RTC_MINUTES);
	137	hour = chrp_cmos_clock_read(RTC_HOURS);
	138	day = chrp_cmos_clock_read(RTC_DAY_OF_MONTH);
	139	mon = chrp_cmos_clock_read(RTC_MONTH);
	140	year = chrp_cmos_clock_read(RTC_YEAR);
4dc12ec7	141	} while (sec != chrp_cmos_clock_read(RTC_SECONDS));
bbd0abda PM	142
bbd0abda PM	143	if (!(chrp_cmos_clock_read(RTC_CONTROL) & RTC_DM_BINARY) \|\| RTC_ALWAYS_BCD) {
8f6ba492 AB	144	sec = bcd2bin(sec);
	145	min = bcd2bin(min);
	146	hour = bcd2bin(hour);
	147	day = bcd2bin(day);
	148	mon = bcd2bin(mon);
	149	year = bcd2bin(year);
bbd0abda	150	}
49e16b7b	151	if (year < 70)
bbd0abda PM	152	year += 100;
	153	tm->tm_sec = sec;
	154	tm->tm_min = min;
	155	tm->tm_hour = hour;
	156	tm->tm_mday = day;
	157	tm->tm_mon = mon;
	158	tm->tm_year = year;
	159	}