[linux-2.6-block.git] / arch / powerpc / platforms / maple / time.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  (c) Copyright 2004 Benjamin Herrenschmidt (benh@kernel.crashing.org),
 *                     IBM Corp. 
 */

#undef DEBUG

#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/init.h>
#include <linux/time.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <linux/interrupt.h>
#include <linux/mc146818rtc.h>
#include <linux/bcd.h>
#include <linux/of_address.h>

#include <asm/sections.h>
#include <asm/io.h>
#include <asm/machdep.h>
#include <asm/time.h>

#include "maple.h"

#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif

static int maple_rtc_addr;

static int maple_clock_read(int addr)
{
	outb_p(addr, maple_rtc_addr);
	return inb_p(maple_rtc_addr+1);
}

static void maple_clock_write(unsigned long val, int addr)
{
	outb_p(addr, maple_rtc_addr);
	outb_p(val, maple_rtc_addr+1);
}

void maple_get_rtc_time(struct rtc_time *tm)
{
	do {
		tm->tm_sec = maple_clock_read(RTC_SECONDS);
		tm->tm_min = maple_clock_read(RTC_MINUTES);
		tm->tm_hour = maple_clock_read(RTC_HOURS);
		tm->tm_mday = maple_clock_read(RTC_DAY_OF_MONTH);
		tm->tm_mon = maple_clock_read(RTC_MONTH);
		tm->tm_year = maple_clock_read(RTC_YEAR);
	} while (tm->tm_sec != maple_clock_read(RTC_SECONDS));

	if (!(maple_clock_read(RTC_CONTROL) & RTC_DM_BINARY)
	    || RTC_ALWAYS_BCD) {
		tm->tm_sec = bcd2bin(tm->tm_sec);
		tm->tm_min = bcd2bin(tm->tm_min);
		tm->tm_hour = bcd2bin(tm->tm_hour);
		tm->tm_mday = bcd2bin(tm->tm_mday);
		tm->tm_mon = bcd2bin(tm->tm_mon);
		tm->tm_year = bcd2bin(tm->tm_year);
	  }
	if ((tm->tm_year + 1900) < 1970)
		tm->tm_year += 100;

	tm->tm_wday = -1;
}

int maple_set_rtc_time(struct rtc_time *tm)
{
	unsigned char save_control, save_freq_select;
	int sec, min, hour, mon, mday, year;

	spin_lock(&rtc_lock);

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

	maple_clock_write((save_control|RTC_SET), RTC_CONTROL);

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

	maple_clock_write((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);

	sec = tm->tm_sec;
	min = tm->tm_min;
	hour = tm->tm_hour;
	mon = tm->tm_mon;
	mday = tm->tm_mday;
	year = tm->tm_year;

	if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
		sec = bin2bcd(sec);
		min = bin2bcd(min);
		hour = bin2bcd(hour);
		mon = bin2bcd(mon);
		mday = bin2bcd(mday);
		year = bin2bcd(year);
	}
	maple_clock_write(sec, RTC_SECONDS);
	maple_clock_write(min, RTC_MINUTES);
	maple_clock_write(hour, RTC_HOURS);
	maple_clock_write(mon, RTC_MONTH);
	maple_clock_write(mday, RTC_DAY_OF_MONTH);
	maple_clock_write(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
	 */
	maple_clock_write(save_control, RTC_CONTROL);
	maple_clock_write(save_freq_select, RTC_FREQ_SELECT);

	spin_unlock(&rtc_lock);

	return 0;
}

static struct resource rtc_iores = {
	.name = "rtc",
	.flags = IORESOURCE_IO | IORESOURCE_BUSY,
};

time64_t __init maple_get_boot_time(void)
{
	struct rtc_time tm;
	struct device_node *rtcs;

	rtcs = of_find_compatible_node(NULL, "rtc", "pnpPNP,b00");
	if (rtcs) {
		struct resource r;
		if (of_address_to_resource(rtcs, 0, &r)) {
			printk(KERN_EMERG "Maple: Unable to translate RTC"
			       " address\n");
			goto bail;
		}
		if (!(r.flags & IORESOURCE_IO)) {
			printk(KERN_EMERG "Maple: RTC address isn't PIO!\n");
			goto bail;
		}
		maple_rtc_addr = r.start;
		printk(KERN_INFO "Maple: Found RTC at IO 0x%x\n",
		       maple_rtc_addr);
	}
 bail:
	of_node_put(rtcs);
	if (maple_rtc_addr == 0) {
		maple_rtc_addr = RTC_PORT(0); /* legacy address */
		printk(KERN_INFO "Maple: No device node for RTC, assuming "
		       "legacy address (0x%x)\n", maple_rtc_addr);
	}

	rtc_iores.start = maple_rtc_addr;
	rtc_iores.end = maple_rtc_addr + 7;
	request_resource(&ioport_resource, &rtc_iores);

	maple_get_rtc_time(&tm);
	return rtc_tm_to_time64(&tm);
}
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4	2	/*
1da177e4 LT	3	* (c) Copyright 2004 Benjamin Herrenschmidt (benh@kernel.crashing.org),
1da177e4 LT	4	* IBM Corp.
1da177e4 LT	5	*/
	6
	7	#undef DEBUG
	8
1da177e4 LT	9	#include <linux/errno.h>
	10	#include <linux/sched.h>
	11	#include <linux/kernel.h>
	12	#include <linux/param.h>
	13	#include <linux/string.h>
	14	#include <linux/mm.h>
	15	#include <linux/init.h>
	16	#include <linux/time.h>
	17	#include <linux/adb.h>
	18	#include <linux/pmu.h>
	19	#include <linux/interrupt.h>
	20	#include <linux/mc146818rtc.h>
	21	#include <linux/bcd.h>
e6f6390a	22	#include <linux/of_address.h>
1da177e4 LT	23
1da177e4 LT	24	#include <asm/sections.h>
1da177e4	25	#include <asm/io.h>
1da177e4 LT	26	#include <asm/machdep.h>
	27	#include <asm/time.h>
	28
0cb7b2af PM	29	#include "maple.h"
0cb7b2af PM	30
1da177e4 LT	31	#ifdef DEBUG
	32	#define DBG(x...) printk(x)
	33	#else
	34	#define DBG(x...)
	35	#endif
	36
1da177e4 LT	37	static int maple_rtc_addr;
	38
	39	static int maple_clock_read(int addr)
	40	{
	41	outb_p(addr, maple_rtc_addr);
	42	return inb_p(maple_rtc_addr+1);
	43	}
	44
	45	static void maple_clock_write(unsigned long val, int addr)
	46	{
	47	outb_p(addr, maple_rtc_addr);
	48	outb_p(val, maple_rtc_addr+1);
	49	}
	50
	51	void maple_get_rtc_time(struct rtc_time *tm)
	52	{
6f0d7bd6	53	do {
1da177e4 LT	54	tm->tm_sec = maple_clock_read(RTC_SECONDS);
	55	tm->tm_min = maple_clock_read(RTC_MINUTES);
	56	tm->tm_hour = maple_clock_read(RTC_HOURS);
	57	tm->tm_mday = maple_clock_read(RTC_DAY_OF_MONTH);
	58	tm->tm_mon = maple_clock_read(RTC_MONTH);
	59	tm->tm_year = maple_clock_read(RTC_YEAR);
6f0d7bd6	60	} while (tm->tm_sec != maple_clock_read(RTC_SECONDS));
1da177e4 LT	61
	62	if (!(maple_clock_read(RTC_CONTROL) & RTC_DM_BINARY)
	63	\|\| RTC_ALWAYS_BCD) {
8f6ba492 AB	64	tm->tm_sec = bcd2bin(tm->tm_sec);
	65	tm->tm_min = bcd2bin(tm->tm_min);
	66	tm->tm_hour = bcd2bin(tm->tm_hour);
	67	tm->tm_mday = bcd2bin(tm->tm_mday);
	68	tm->tm_mon = bcd2bin(tm->tm_mon);
	69	tm->tm_year = bcd2bin(tm->tm_year);
1da177e4 LT	70	}
	71	if ((tm->tm_year + 1900) < 1970)
	72	tm->tm_year += 100;
	73
00b912b0	74	tm->tm_wday = -1;
1da177e4 LT	75	}
	76
	77	int maple_set_rtc_time(struct rtc_time *tm)
	78	{
	79	unsigned char save_control, save_freq_select;
	80	int sec, min, hour, mon, mday, year;
	81
	82	spin_lock(&rtc_lock);
	83
	84	save_control = maple_clock_read(RTC_CONTROL); /* tell the clock it's being set */
	85
	86	maple_clock_write((save_control\|RTC_SET), RTC_CONTROL);
	87
	88	save_freq_select = maple_clock_read(RTC_FREQ_SELECT); /* stop and reset prescaler */
	89
	90	maple_clock_write((save_freq_select\|RTC_DIV_RESET2), RTC_FREQ_SELECT);
	91
	92	sec = tm->tm_sec;
	93	min = tm->tm_min;
	94	hour = tm->tm_hour;
	95	mon = tm->tm_mon;
	96	mday = tm->tm_mday;
	97	year = tm->tm_year;
	98
	99	if (!(save_control & RTC_DM_BINARY) \|\| RTC_ALWAYS_BCD) {
8f6ba492 AB	100	sec = bin2bcd(sec);
	101	min = bin2bcd(min);
	102	hour = bin2bcd(hour);
	103	mon = bin2bcd(mon);
	104	mday = bin2bcd(mday);
	105	year = bin2bcd(year);
1da177e4 LT	106	}
	107	maple_clock_write(sec, RTC_SECONDS);
	108	maple_clock_write(min, RTC_MINUTES);
	109	maple_clock_write(hour, RTC_HOURS);
	110	maple_clock_write(mon, RTC_MONTH);
	111	maple_clock_write(mday, RTC_DAY_OF_MONTH);
	112	maple_clock_write(year, RTC_YEAR);
	113
	114	/* The following flags have to be released exactly in this order,
	115	* otherwise the DS12887 (popular MC146818A clone with integrated
	116	* battery and quartz) will not reset the oscillator and will not
	117	* update precisely 500 ms later. You won't find this mentioned in
	118	* the Dallas Semiconductor data sheets, but who believes data
	119	* sheets anyway ... -- Markus Kuhn
	120	*/
	121	maple_clock_write(save_control, RTC_CONTROL);
	122	maple_clock_write(save_freq_select, RTC_FREQ_SELECT);
	123
	124	spin_unlock(&rtc_lock);
	125
	126	return 0;
	127	}
	128
a097a35c SB	129	static struct resource rtc_iores = {
a097a35c SB	130	.name = "rtc",
961292e6	131	.flags = IORESOURCE_IO \| IORESOURCE_BUSY,
a097a35c SB	132	};
a097a35c SB	133
5bfd6435	134	time64_t __init maple_get_boot_time(void)
1da177e4	135	{
143a1dec	136	struct rtc_time tm;
1da177e4 LT	137	struct device_node *rtcs;
1da177e4 LT	138
4c882b01 BH	139	rtcs = of_find_compatible_node(NULL, "rtc", "pnpPNP,b00");
	140	if (rtcs) {
	141	struct resource r;
	142	if (of_address_to_resource(rtcs, 0, &r)) {
	143	printk(KERN_EMERG "Maple: Unable to translate RTC"
	144	" address\n");
	145	goto bail;
	146	}
	147	if (!(r.flags & IORESOURCE_IO)) {
	148	printk(KERN_EMERG "Maple: RTC address isn't PIO!\n");
	149	goto bail;
	150	}
	151	maple_rtc_addr = r.start;
	152	printk(KERN_INFO "Maple: Found RTC at IO 0x%x\n",
	153	maple_rtc_addr);
	154	}
	155	bail:
23b14818	156	of_node_put(rtcs);
4c882b01	157	if (maple_rtc_addr == 0) {
1da177e4 LT	158	maple_rtc_addr = RTC_PORT(0); /* legacy address */
	159	printk(KERN_INFO "Maple: No device node for RTC, assuming "
	160	"legacy address (0x%x)\n", maple_rtc_addr);
	161	}
a097a35c SB	162
	163	rtc_iores.start = maple_rtc_addr;
	164	rtc_iores.end = maple_rtc_addr + 7;
	165	request_resource(&ioport_resource, &rtc_iores);
	166
143a1dec	167	maple_get_rtc_time(&tm);
5bfd6435	168	return rtc_tm_to_time64(&tm);
1da177e4 LT	169	}
1da177e4 LT	170