/*
 * (C) Copyright 2018 Leo C. <erbl259-lmu@yahoo.de>
 *
 * SPDX-License-Identifier:	GPL-2.0
 */

#include "cmd_cpu.h"
//#include <ctype.h>
//#include <util/atomic.h>

#include "z80-if.h"
#include "con-utils.h"
//#include "env.h"
#include "eval_arg.h"
#include "timer.h"
#include "getopt-min.h"
//#include "debug.h"

/* hack to get Z180 loadfile into flash memory */
#define const const FLASH
#include "../z180/cpuinfo.h"
#undef const


static const FLASH char * const FLASH cpu_strings[] = {
	FSTR("Unknown CPU"),
	FSTR("8080"),
	FSTR("8085"),
	FSTR("Z80"),
	FSTR("x180"),
	FSTR("HD64180"),
	FSTR("Z80180"),
	FSTR("Z80S180"),
};

command_ret_t do_cpuchk(cmd_tbl_t *cmdtp UNUSED, uint_fast8_t flag UNUSED, int argc UNUSED, char * const argv[] UNUSED)
{
	uint8_t done = 0;
	uint8_t cputype;
	ERRNUM err = ESUCCESS;
	uint8_t ram_save[cpuinfo_length];

	if (z80_bus_state() & ZST_RUNNING) {
		err = ERUNNING;
	} else {
		z80_bus_request_or_exit();
		z80_read_block(ram_save, 0, cpuinfo_length);
		z80_load_mem(0, cpuinfo,
					&cpuinfo_sections,
					cpuinfo_address,
					cpuinfo_length_of_sections);
		z80_bus_cmd(Release);

		if (argv[1] && (argv[1][0] == 'n'))
			goto donot;

		z80_bus_cmd(Run);

		clear_ctrlc();		/* forget any previous Control C */
		while (done != 0xFF) {
			_delay_ms(8);
			/* check for ctrl-c to abort... */
			if (had_ctrlc() || ctrlc()) {
				err = EINTR;
				break;
			}
			z80_bus_cmd(Request);
			done = z80_read(3);
			if (done == 0xFF)
				cputype = z80_read(4);
			z80_bus_cmd(Release);
		}
		z80_bus_cmd(Reset);
		z80_bus_cmd(Request);
//		z80_write_block(ram_save, 0, cpuinfo_length);
		z80_bus_cmd(Release);
	}

donot:

	if (err)
		cmd_error(CMD_RET_FAILURE, err, NULL);

	if (done == 0xFF) {
		if (cputype >= ARRAY_SIZE(cpu_strings))
			cputype = 0;
		printf_P(PSTR("Detected CPU: %S\n"), cpu_strings[cputype]);
	}

	return CMD_RET_SUCCESS;
}

/*
 * delay for <count> ms...
 */
static void	test_delay(uint32_t count)
{
	uint32_t ts = get_timer(0);

	while (get_timer(ts) < count);
}

command_ret_t do_cpu_test(cmd_tbl_t *cmdtp UNUSED, uint_fast8_t flag UNUSED, int argc, char * const argv[])
{

	uint32_t pulsewidth = 10; /* ms */

	/* reset getopt() */
	optind = 0;

	int opt;
	while ((opt = getopt(argc, argv, PSTR("t:"))) != -1) {
		switch (opt) {
		case 't':
			pulsewidth = eval_arg(optarg, NULL);
			break;
		default: /* '?' */
			return CMD_RET_USAGE;
		}
	}

	if ((z80_bus_state() & ZST_ACQUIRED) != RESET)
		cmd_error(CMD_RET_FAILURE, ERUNNING, NULL);

	clear_ctrlc();		/* forget any previous Control C */
	do {
		z80_bus_cmd(Request);
		test_delay(pulsewidth);
		z80_bus_cmd(Release);
		test_delay(pulsewidth);
	} while (!(had_ctrlc() || ctrlc()));

	return CMD_RET_SUCCESS;
}

#if 0
command_ret_t do_cpu_freq(cmd_tbl_t *cmdtp UNUSED, int flag UNUSED, int argc, char * const argv[])
{
	bool silent = false;
	bool write_env = false;
	bool load_loop = true;
	uint8_t lcycles = 18;
	uint16_t timeout = 1000;

	uint8_t eicrb_save;
	uint8_t eimsk_save;
	uint8_t mem_save[cpuinfo_length];

	/* reset getopt() */
	optind = 0;

	int opt;
	while ((opt = getopt(argc, argv, PSTR("swnc:t:"))) != -1) {
		switch (opt) {
		case 's':
			silent = true;
			break;
		case 'w':
			write_env = true;
			break;
		case 'n':
			load_loop = false;
			break;
		case 'c':
			lcycles = eval_arg(optarg, NULL);
			break;
		case 't':
			lcycles = eval_arg(optarg, NULL);
			break;
		default: /* '?' */
			return CMD_RET_USAGE;
		}
	}

	if (z80_bus_state() & ZST_RUNNING) {
		if (!silent)
			printf_P(PSTR("Frequency measuring failed. CPU allready running!\n"));
		return CMD_RET_FAILURE;
	}

	ATOMIC_BLOCK(ATOMIC_FORCEON) {
		/* Save state and disable INT6 */
		eimsk_save = EIMSK;
		EIMSK &= ~_BV(INT6);
		/* Save state and set INT6 for falling edge */
		eicrb_save = EICRB;
		EICRB = (eicrb_save & ~(0b11 << ISC60)) | (0b10 << ISC60);
	}

	z80_bus_cmd(Request);
	if (load_loop) {
		z80_read_block(mem_save, 0, cpuinfo_length);
		z80_load_mem(0, cpuinfo,
					&cpuinfo_sections,
					cpuinfo_address,
					cpuinfo_length_of_sections);
	}
	z80_bus_cmd(Run);
	z80_bus_cmd(Release);

	uint32_t cpu_freq = z80_measure_phi(lcycles, true, timeout);

	z80_bus_cmd(Reset);
	z80_bus_cmd(Request);
	if (load_loop)
		z80_write_block(mem_save, 0, cpuinfo_length);
	z80_bus_cmd(Release);

	ATOMIC_BLOCK(ATOMIC_FORCEON) {
		/* Restore INT6 */
		eicrb_save = EICRB;
		EICRB = (EICRB & ~(0b11 << ISC60)) | (eicrb_save & (0b11 << ISC60));
		if ((eimsk_save & _BV(INT6)) != 0)
			EIMSK |= _BV(INT6);
		/* Reset pending int */
		EIFR = _BV(INTF6);
	}

	if (!silent) {
		if (cpu_freq != 0)
			printf_P(PSTR("%luHz\n"), cpu_freq);
		else
			printf_P(PSTR("No CPU clock or input frequency to low!\n"));
	}

	if (write_env) {
		if (setenv_ulong(PSTR(ENV_CPU_FREQ), cpu_freq)) {
			if (!silent)
				printf_P(PSTR("'SETENV (%S, %lu)' failed!\n"), PSTR(ENV_CPU_FREQ), cpu_freq);
			return CMD_RET_FAILURE;
		}
	}

	return CMD_RET_SUCCESS;
}
#endif

/*
 * command table for fat subcommands
 */

cmd_tbl_t cmd_tbl_cpu[] = {
CMD_TBL_ITEM(
	chkcpu,	CONFIG_SYS_MAXARGS,	CTBL_RPT,	do_cpuchk,
	"Check CPU",
	""
),
CMD_TBL_ITEM(
	test,	CONFIG_SYS_MAXARGS,	1,	do_cpu_test,
	"Do bus request/release cycles",
	"[-t pulsewidth]"
),
#if 0
CMD_TBL_ITEM(
	freq,	CONFIG_SYS_MAXARGS,	1,	do_cpu_freq,
	"Measure cpu frequency",
	"[-swn] [-c loopcycles]\n"
	"     -s  Supress output (silent)\n"
	"     -w  Write result to environment variable '"ENV_CPU_FREQ"'"
),
#endif
CMD_TBL_ITEM(
	help,	CONFIG_SYS_MAXARGS,	CTBL_RPT,	do_help,
	"Print sub command description/usage",
	"\n"
	"       - print brief description of all sub commands\n"
	"fat help command ...\n"
	"       - print detailed usage of sub cmd 'command'"
),

/* This does not use the CMD_TBL_ITEM macro as ? can't be used in symbol names */
	{FSTR("?"),   CONFIG_SYS_MAXARGS, 1, do_help,
	 NULL,
#ifdef  CONFIG_SYS_LONGHELP
	FSTR(""),
#endif /* CONFIG_SYS_LONGHELP */
	NULL,
#ifdef CONFIG_AUTO_COMPLETE
	NULL,
#endif
},
/* Mark end of table */
CMD_TBL_END(cmd_tbl_cpu)
};


command_ret_t do_cpu(cmd_tbl_t *cmdtp UNUSED, uint_fast8_t flag UNUSED, int argc UNUSED, char * const argv[] UNUSED)
{
	//puts_P(PSTR("Huch?"));

	return CMD_RET_USAGE;
}


#if 0
/*
 * Z180 Single Step Functions
 *
 */


#define P_RUN		PORTG
#define RUN			1
#define DDR_RUN		DDRG
#define P_STEP		PORTG
#define STEP		0
#define DDR_STEP	DDRG
#define P_WAIT		PORTG
#define WAIT		2
#define DDR_WAIT	DDRG
/* All three signals are on the same Port (PortG) */
#define PORT_SS		PORTG
#define DDR_SS		DDRG
#define PIN_SS		PING

static bool ss_available;

int single_step_setup(void)
{
	ss_available = false;

#if 0
	if (z80_bus_state() & ZST_RUNNING ||
			!(z80_bus_cmd(Request) & ZST_ACQUIRED))
		return  -1;
#endif

	/* STEP, RUN output, WAIT input */

	PORT_SS |= _BV(RUN) | _BV(STEP);
	DDR_SS |= _BV(RUN) | _BV(STEP);
	DDR_SS &= ~_BV(WAIT);

	/* RUN high, MREQ pulse --> WAIT should be low */
	z80_mreq_pulse();

	if ((PIN_SS & _BV(WAIT)) == 0) {

		/* RUN high, STEP pulse --> WAIT should be high */
		PIN_SS = _BV(STEP);
		PIN_SS = _BV(STEP);
		if ((PIN_SS & _BV(WAIT)) != 0) {

			/* RUN high, MREQ pulse --> WAIT should be low */
			z80_mreq_pulse();
			if ((PIN_SS & _BV(WAIT)) == 0) {

				/* RUN low --> WAIT should be high */
				PIN_SS = _BV(RUN);
				if ((PIN_SS & _BV(WAIT)) != 0) {

					/* RUN low, STEP pulse --> WAIT should be high */
					PIN_SS = _BV(STEP);
					PIN_SS = _BV(STEP);
					if ((PIN_SS & _BV(WAIT)) != 0) {

						/* all tests passed */
						ss_available = true;
					}
				}
			}
		}
	}

	if (!ss_available) {
		DDR_SS &= ~(_BV(STEP) | _BV(RUN));
		PORT_SS |= _BV(RUN) | _BV(STEP);
	}

	return ss_available ? 0 : -1;
}
#endif