/* $Id: s3c2410_rtc.c,v 1.5 2008/12/11 12:18:17 ecd Exp $
 */

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <sys/time.h>
#include <time.h>
#include <errno.h>

#include <x49gp.h>
#include <s3c2410.h>
#include <s3c2410_intc.h>


typedef struct {
	uint32_t			rtccon;
	uint32_t			ticnt;
	uint32_t			rtcalm;
	uint32_t			almsec;
	uint32_t			almmin;
	uint32_t			almhour;
	uint32_t			almdate;
	uint32_t			almmon;
	uint32_t			almyear;
	uint32_t			rtcrst;
	uint32_t			bcdsec;
	uint32_t			bcdmin;
	uint32_t			bcdhour;
	uint32_t			bcddate;
	uint32_t			bcdday;
	uint32_t			bcdmon;
	uint32_t			bcdyear;

	unsigned int		nr_regs;
	s3c2410_offset_t	*regs;

	x49gp_t			*x49gp;
	x49gp_timer_t		*tick_timer;
	x49gp_timer_t		*alarm_timer;
	int64_t			interval;	/* us */
	int64_t			expires;	/* us */
} s3c2410_rtc_t;


static int
s3c2410_rtc_data_init(s3c2410_rtc_t *rtc)
{
	s3c2410_offset_t regs[] = {
		S3C2410_OFFSET(RTC, RTCCON, 0x00, rtc->rtccon),
		S3C2410_OFFSET(RTC, TICNT, 0x00, rtc->ticnt),
		S3C2410_OFFSET(RTC, RTCALM, 0x00, rtc->rtcalm),
		S3C2410_OFFSET(RTC, ALMSEC, 0x00, rtc->almsec),
		S3C2410_OFFSET(RTC, ALMMIN, 0x00, rtc->almmin),
		S3C2410_OFFSET(RTC, ALMHOUR, 0x00, rtc->almhour),
		S3C2410_OFFSET(RTC, ALMDATE, 0x01, rtc->almdate),
		S3C2410_OFFSET(RTC, ALMMON, 0x01, rtc->almmon),
		S3C2410_OFFSET(RTC, ALMYEAR, 0x00, rtc->almyear),
		S3C2410_OFFSET(RTC, RTCRST, 0x00, rtc->rtcrst),
		S3C2410_OFFSET(RTC, BCDSEC, 0, rtc->bcdsec),
		S3C2410_OFFSET(RTC, BCDMIN, 0, rtc->bcdmin),
		S3C2410_OFFSET(RTC, BCDHOUR, 0, rtc->bcdhour),
		S3C2410_OFFSET(RTC, BCDDATE, 0, rtc->bcddate),
		S3C2410_OFFSET(RTC, BCDDAY, 0, rtc->bcdday),
		S3C2410_OFFSET(RTC, BCDMON, 0, rtc->bcdmon),
		S3C2410_OFFSET(RTC, BCDYEAR, 0, rtc->bcdyear)
	};

	memset(rtc, 0, sizeof(s3c2410_rtc_t));

	rtc->regs = malloc(sizeof(regs));
	if (NULL == rtc->regs) {
		fprintf(stderr, "%s:%u: Out of memory\n",
			__FUNCTION__, __LINE__);
		return -ENOMEM;
	}

	memcpy(rtc->regs, regs, sizeof(regs));
	rtc->nr_regs = sizeof(regs) / sizeof(regs[0]);

	return 0;
}

static __inline__ uint32_t bin2bcd(uint32_t bin)
{
	return ((bin / 10) << 4) | (bin % 10);
}

static __inline__ uint32_t bcd2bin(uint32_t bcd)
{
	return ((bcd >> 4) * 10) + (bcd & 0x0f);
}

static void
s3c2410_rtc_timeout(void * user_data)
{
	s3c2410_rtc_t *rtc = user_data;
	x49gp_t *x49gp = rtc->x49gp;
	int64_t now, us;

	if (!(rtc->ticnt & 0x80)) {
		return;
	}

#ifdef DEBUG_S3C2410_RTC
	printf("RTC: assert TICK interrupt\n");
#endif

	s3c2410_intc_assert(x49gp, INT_TICK, 0);

	now = x49gp_get_clock();
	while (rtc->expires <= now) {
		rtc->expires += rtc->interval;
	}

	us = rtc->expires - now;
	if (us < 1000)
		us = 1000;

#ifdef DEBUG_S3C2410_RTC
	printf("RTC: restart TICK timer (%llu us)\n", (unsigned long long) us);
#endif

	x49gp_mod_timer(rtc->tick_timer, rtc->expires);
}

static int
s3c2410_rtc_set_ticnt(s3c2410_rtc_t *rtc)
{
	int64_t now, us;

	if (x49gp_timer_pending(rtc->tick_timer)) {
		x49gp_del_timer(rtc->tick_timer);
#ifdef DEBUG_S3C2410_RTC
		printf("RTC: stop TICK timer\n");
#endif
	}

	if (!(rtc->ticnt & 0x80)) {
		return 0;
	}

	us = (((rtc->ticnt & 0x7f) + 1) * 1000000) / 128;

	rtc->interval = us;
	if (rtc->interval < 1000)
		rtc->interval = 1000;

	now = x49gp_get_clock();
	rtc->expires = now + rtc->interval;

	us = rtc->expires - now;
	if (us < 1000)
		us = 1000;

#ifdef DEBUG_S3C2410_RTC
	printf("RTC: start TICK timer (%lld us)\n", (unsigned long long) us);
#endif

	x49gp_mod_timer(rtc->tick_timer, rtc->expires);
	return 0;
}

static void
s3c2410_rtc_alarm(void * user_data)
{
	s3c2410_rtc_t *rtc = user_data;
	x49gp_t *x49gp = rtc->x49gp;
	struct tm *tm;
	struct timeval tv;
	int64_t now, us;
	int match = 1;

	if (!(rtc->rtcalm & 0x40)) {
		return;
	}

	gettimeofday(&tv, NULL);
	tm = localtime(&tv.tv_sec);

	now = x49gp_get_clock();
	us = 1000000LL - tv.tv_usec;

	if (match && (rtc->rtcalm & 0x01)) {
		if (tm->tm_sec != bcd2bin(rtc->almsec))
			match = 0;
	}
	if (match && (rtc->rtcalm & 0x02)) {
		if (tm->tm_min != bcd2bin(rtc->almmin))
			match = 0;
	}
	if (match && (rtc->rtcalm & 0x04)) {
		if (tm->tm_hour != bcd2bin(rtc->almhour))
			match = 0;
	}
	if (match && (rtc->rtcalm & 0x08)) {
		if (tm->tm_mday != bcd2bin(rtc->almdate))
			match = 0;
	}
	if (match && (rtc->rtcalm & 0x10)) {
		if ((tm->tm_mon + 1) != bcd2bin(rtc->almmon))
			match = 0;
	}
	if (match && (rtc->rtcalm & 0x20)) {
		if ((tm->tm_year % 100) != bcd2bin(rtc->almyear))
			match = 0;
	}

	if (match) {
#ifdef DEBUG_S3C2410_RTC
		printf("RTC: assert ALARM interrupt\n");
#endif
		s3c2410_intc_assert(x49gp, INT_RTC, 0);
	}

#ifdef DEBUG_S3C2410_RTC
	printf("RTC: reload ALARM timer (%lld us)\n", (unsigned long long) us);
#endif

	x49gp_mod_timer(rtc->alarm_timer, now + us);
}

static int
s3c2410_rtc_set_rtcalm(s3c2410_rtc_t *rtc)
{
	struct timeval tv;
	int64_t now, us;

	if (!(rtc->rtcalm & 0x40)) {
		x49gp_del_timer(rtc->alarm_timer);
		return 0;
	}

	gettimeofday(&tv, NULL);

	now = x49gp_get_clock();
	us = 1000000LL - tv.tv_usec;

#ifdef DEBUG_S3C2410_RTC
	printf("RTC: start ALARM timer (%lld us)\n", (unsigned long long) us);
#endif

	x49gp_mod_timer(rtc->alarm_timer, now + us);
	return 0;
}

static uint32_t
s3c2410_rtc_read(void *opaque, target_phys_addr_t offset)
{
	s3c2410_rtc_t *rtc = opaque;
	s3c2410_offset_t *reg;

	if (! S3C2410_OFFSET_OK(rtc, offset)) {
		return ~(0);
	}

	reg = S3C2410_OFFSET_ENTRY(rtc, offset);

	if (S3C2410_RTC_BCDSEC <= offset && offset <= S3C2410_RTC_BCDYEAR) {
		struct tm *tm;
		struct timeval tv;

		gettimeofday(&tv, NULL);
		tm = localtime(&tv.tv_sec);

		switch (offset) {
		case S3C2410_RTC_BCDSEC:
			*(reg->datap) = bin2bcd(tm->tm_sec);
			break;
		case S3C2410_RTC_BCDMIN:
			*(reg->datap) = bin2bcd(tm->tm_min);
			break;
		case S3C2410_RTC_BCDHOUR:
			*(reg->datap) = bin2bcd(tm->tm_hour);
			break;
		case S3C2410_RTC_BCDDATE:
			*(reg->datap) = bin2bcd(tm->tm_mday);
			break;
		case S3C2410_RTC_BCDDAY:
			*(reg->datap) = bin2bcd(tm->tm_wday + 1);
			break;
		case S3C2410_RTC_BCDMON:
			*(reg->datap) = bin2bcd(tm->tm_mon + 1);
			break;
		case S3C2410_RTC_BCDYEAR:
			*(reg->datap) = bin2bcd(tm->tm_year % 100);
			break;
		}
	}

#ifdef DEBUG_S3C2410_RTC
	printf("read  %s [%08x] %s [%08lx] data %08x\n",
		"s3c2410-rtc", S3C2410_RTC_BASE,
		reg->name, (unsigned long) offset, *(reg->datap));
#endif

	return *(reg->datap);
}

static void
s3c2410_rtc_write(void *opaque, target_phys_addr_t offset, uint32_t data)
{
	s3c2410_rtc_t *rtc = opaque;
	s3c2410_offset_t *reg;

	if (! S3C2410_OFFSET_OK(rtc, offset)) {
		return;
	}

	reg = S3C2410_OFFSET_ENTRY(rtc, offset);

#ifdef DEBUG_S3C2410_RTC
	printf("write %s [%08x] %s [%08lx] data %08x\n",
		"s3c2410-rtc", S3C2410_RTC_BASE,
		reg->name, (unsigned long) offset, data);
#endif

	switch (offset) {
	case S3C2410_RTC_TICNT:
		*(reg->datap) = data;
		s3c2410_rtc_set_ticnt(rtc);
		break;
	case S3C2410_RTC_RTCALM:
		*(reg->datap) = data;
		s3c2410_rtc_set_rtcalm(rtc);
		break;
	default:
		*(reg->datap) = data;
		break;
	}
}

static int
s3c2410_rtc_load(x49gp_module_t *module, GKeyFile *key)
{
	s3c2410_rtc_t *rtc = module->user_data;
	s3c2410_offset_t *reg;
	int error = 0;
	int i;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	for (i = 0; i < rtc->nr_regs; i++) {
		reg = &rtc->regs[i];

		if (NULL == reg->name)
			continue;

		if (x49gp_module_get_u32(module, key, reg->name,
					 reg->reset, reg->datap))
			error = -EAGAIN;
	}

	s3c2410_rtc_set_ticnt(rtc);
	s3c2410_rtc_set_rtcalm(rtc);

	return error;
}

static int
s3c2410_rtc_save(x49gp_module_t *module, GKeyFile *key)
{
	s3c2410_rtc_t *rtc = module->user_data;
	s3c2410_offset_t *reg;
	int i;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	for (i = 0; i < rtc->nr_regs; i++) {
		reg = &rtc->regs[i];

		if (NULL == reg->name)
			continue;

		x49gp_module_set_u32(module, key, reg->name, *(reg->datap));
	}

	return 0;
}

static int
s3c2410_rtc_reset(x49gp_module_t *module, x49gp_reset_t reset)
{
	s3c2410_rtc_t *rtc = module->user_data;
	s3c2410_offset_t *reg;
	int i;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	for (i = 0; i < (S3C2410_RTC_RTCALM >> 2); i++) {
		reg = &rtc->regs[i];

		if (NULL == reg->name)
			continue;

		*(reg->datap) = reg->reset;
	}

	s3c2410_rtc_set_ticnt(rtc);

	return 0;
}

static CPUReadMemoryFunc *s3c2410_rtc_readfn[] =
{
	s3c2410_rtc_read,
	s3c2410_rtc_read,
	s3c2410_rtc_read
};

static CPUWriteMemoryFunc *s3c2410_rtc_writefn[] =
{
	s3c2410_rtc_write,
	s3c2410_rtc_write,
	s3c2410_rtc_write
};

static int
s3c2410_rtc_init(x49gp_module_t *module)
{
	s3c2410_rtc_t *rtc;
	int iotype;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	rtc = malloc(sizeof(s3c2410_rtc_t));
	if (NULL == rtc) {
		fprintf(stderr, "%s: %s:%u: Out of memory\n",
			module->x49gp->progname, __FUNCTION__, __LINE__);
		return -ENOMEM;
	}
	if (s3c2410_rtc_data_init(rtc)) {
		free(rtc);
		return -ENOMEM;
	}

	module->user_data = rtc;
	rtc->x49gp = module->x49gp;

	rtc->tick_timer = x49gp_new_timer(X49GP_TIMER_REALTIME,
					  s3c2410_rtc_timeout, rtc);
	rtc->alarm_timer = x49gp_new_timer(X49GP_TIMER_REALTIME,
					   s3c2410_rtc_alarm, rtc);

	iotype = cpu_register_io_memory(s3c2410_rtc_readfn,
					s3c2410_rtc_writefn, rtc);
#ifdef DEBUG_S3C2410_RTC
	printf("%s: iotype %08x\n", __FUNCTION__, iotype);
#endif
	cpu_register_physical_memory(S3C2410_RTC_BASE, S3C2410_MAP_SIZE, iotype);

	return 0;
}

static int
s3c2410_rtc_exit(x49gp_module_t *module)
{
	s3c2410_rtc_t *rtc;

#ifdef DEBUG_X49GP_MODULES
	printf("%s: %s:%u\n", module->name, __FUNCTION__, __LINE__);
#endif

	if (module->user_data) {
		rtc = module->user_data;
		if (rtc->regs)
			free(rtc->regs);
		free(rtc);
	}

	x49gp_module_unregister(module);
	free(module);

	return 0;
}

int
x49gp_s3c2410_rtc_init(x49gp_t *x49gp)
{
	x49gp_module_t *module;

	if (x49gp_module_init(x49gp, "s3c2410-rtc",
			      s3c2410_rtc_init,
			      s3c2410_rtc_exit,
			      s3c2410_rtc_reset,
			      s3c2410_rtc_load,
			      s3c2410_rtc_save,
			      NULL, &module)) {
		return -1;
	}

	return x49gp_module_register(module);
}