/*
 * This file is part of the flashrom project.
 *
 * SPDX-License-Identifier: GPL-2.0-only
 * SPDX-FileCopyrightText: 2007, 2008, 2009 Carl-Daniel Hailfinger
 * SPDX-FileCopyrightText: 2008 Ronald Hoogenboom <ronald@zonnet.nl>
 * SPDX-FileCopyrightText: 2008 coresystems GmbH
 */

/*
 * Contains the ITE IT87* SPI specific routines
 */

#include <string.h>
#include <stdbool.h>
#include <stdlib.h>
#include <errno.h>
#include "chipdrivers.h"
#include "programmer.h"
#include "hwaccess_physmap.h"
#include "hwaccess_x86_io.h"
#include "spi.h"
#include "platform/udelay.h"

#define ITE_SUPERIO_PORT1	0x2e
#define ITE_SUPERIO_PORT2	0x4e

#define CHIP_ID_BYTE1_REG	0x20
#define CHIP_ID_BYTE2_REG	0x21
#define CHIP_VER_REG		0x22

struct it8716f_spi_data {
	uint16_t flashport;
	/* use fast 33MHz SPI (<>0) or slow 16MHz (0) */
	bool fast_spi;
};

static int get_data_from_context(const struct flashctx *flash, struct it8716f_spi_data **data)
{
	if (!flash || !flash->mst || !flash->mst->spi.data) {
		msg_perr("Unable to extract fd from flash context.\n");
		return SPI_GENERIC_ERROR;
	}
	*data = (struct it8716f_spi_data *)flash->mst->spi.data;

	return 0;
}

/* Helper functions for most recent ITE IT87xx Super I/O chips */
void enter_conf_mode_ite(uint16_t port)
{
	OUTB(0x87, port);
	OUTB(0x01, port);
	OUTB(0x55, port);
	if (port == ITE_SUPERIO_PORT1)
		OUTB(0x55, port);
	else
		OUTB(0xaa, port);
}

void exit_conf_mode_ite(uint16_t port)
{
	sio_write(port, 0x02, 0x02);
}

static uint16_t probe_id_ite(uint16_t port)
{
	uint16_t id;

	enter_conf_mode_ite(port);
	id = sio_read(port, CHIP_ID_BYTE1_REG) << 8;
	id |= sio_read(port, CHIP_ID_BYTE2_REG);
	exit_conf_mode_ite(port);

	return id;
}

void probe_superio_ite(void)
{
	struct superio s = {0};
	uint16_t ite_ports[] = {ITE_SUPERIO_PORT1, ITE_SUPERIO_PORT2, 0};
	uint16_t *i = ite_ports;

	s.vendor = SUPERIO_VENDOR_ITE;
	for (; *i; i++) {
		s.port = *i;
		s.model = probe_id_ite(s.port);
		switch (s.model >> 8) {
		case 0x82:
		case 0x86:
		case 0x87:
			/* FIXME: Print revision for all models? */
			msg_pdbg("Found ITE Super I/O, ID 0x%04hx on port 0x%x\n", s.model, s.port);
			register_superio(s);
			break;
		case 0x85:
			msg_pdbg("Found ITE EC, ID 0x%04hx, Rev 0x%02x on port 0x%x.\n",
				 s.model, sio_read(s.port, CHIP_VER_REG), s.port);
			register_superio(s);
			break;
		}
	}

	return;
}

/* Page size is usually 256 bytes */
static int it8716f_spi_page_program(struct flashctx *flash, const uint8_t *buf, unsigned int start)
{
	unsigned int i;
	int result;
	chipaddr bios = flash->virtual_memory;
	struct it8716f_spi_data *data;

	if (get_data_from_context(flash, &data) < 0)
		return SPI_GENERIC_ERROR;

	result = spi_write_enable(flash);
	if (result)
		return result;
	/* FIXME: The command below seems to be redundant or wrong. */
	OUTB(0x06, data->flashport + 1);
	OUTB(((2 + (data->fast_spi ? 1 : 0)) << 4), data->flashport);
	for (i = 0; i < flash->chip->page_size; i++)
		mmio_writeb(buf[i], (void *)(bios + start + i));
	OUTB(0, data->flashport);
	/* Wait until the Write-In-Progress bit is cleared.
	 * This usually takes 1-10 ms, so wait in 1 ms steps.
	 *
	 * FIXME: This should timeout after some number of retries.
	 */
	while (true) {
		uint8_t status;
		int ret = spi_read_register(flash, STATUS1, &status);
		if (ret)
		       return ret;

		if((status & SPI_SR_WIP) == 0)
			return 0;

		default_delay(1000);
	}
	return 0;
}

/*
 * The IT8716F only supports commands with length 1,2,4,5 bytes including
 * command byte and can not read more than 3 bytes from the device.
 *
 * This function expects writearr[0] to be the first byte sent to the device,
 * whereas the IT8716F splits commands internally into address and non-address
 * commands with the address in inverse wire order. That's why the register
 * ordering in case 4 and 5 may seem strange.
 */
static int it8716f_spi_send_command(const struct flashctx *flash,
				    unsigned int writecnt, unsigned int readcnt,
				    const unsigned char *writearr,
				    unsigned char *readarr)
{
	uint8_t busy, writeenc;
	struct it8716f_spi_data *data;

	if (get_data_from_context(flash, &data) < 0)
		return SPI_GENERIC_ERROR;

	do {
		busy = INB(data->flashport) & 0x80;
	} while (busy);
	if (readcnt > 3) {
		msg_pinfo("%s called with unsupported readcnt %i.\n",
			  __func__, readcnt);
		return SPI_INVALID_LENGTH;
	}
	switch (writecnt) {
	case 1:
		OUTB(writearr[0], data->flashport + 1);
		writeenc = 0x0;
		break;
	case 2:
		OUTB(writearr[0], data->flashport + 1);
		OUTB(writearr[1], data->flashport + 7);
		writeenc = 0x1;
		break;
	case 4:
		OUTB(writearr[0], data->flashport + 1);
		OUTB(writearr[1], data->flashport + 4);
		OUTB(writearr[2], data->flashport + 3);
		OUTB(writearr[3], data->flashport + 2);
		writeenc = 0x2;
		break;
	case 5:
		OUTB(writearr[0], data->flashport + 1);
		OUTB(writearr[1], data->flashport + 4);
		OUTB(writearr[2], data->flashport + 3);
		OUTB(writearr[3], data->flashport + 2);
		OUTB(writearr[4], data->flashport + 7);
		writeenc = 0x3;
		break;
	default:
		msg_pinfo("%s called with unsupported writecnt %i.\n",
			  __func__, writecnt);
		return SPI_INVALID_LENGTH;
	}
	/*
	 * Start IO, 33 or 16 MHz, readcnt input bytes, writecnt output bytes.
	 * Note:
	 * We can't use writecnt directly, but have to use a strange encoding.
	 */
	OUTB(((0x4 + (data->fast_spi ? 1 : 0)) << 4)
		| ((readcnt & 0x3) << 2) | (writeenc), data->flashport);

	if (readcnt > 0) {
		unsigned int i;

		do {
			busy = INB(data->flashport) & 0x80;
		} while (busy);

		for (i = 0; i < readcnt; i++)
			readarr[i] = INB(data->flashport + 5 + i);
	}

	return 0;
}

/*
 * IT8716F only allows maximum of 512 kb SPI mapped to LPC memory cycles
 * Need to read this big flash using firmware cycles 3 byte at a time.
 */
static int it8716f_spi_chip_read(struct flashctx *flash, uint8_t *buf,
				 unsigned int start, unsigned int len)
{
	struct it8716f_spi_data *data;

	if (get_data_from_context(flash, &data) < 0)
		return SPI_GENERIC_ERROR;

	data->fast_spi = false;

	/* FIXME: Check if someone explicitly requested to use IT87 SPI although
	 * the mainboard does not use IT87 SPI translation. This should be done
	 * via a programmer parameter for the internal programmer.
	 */
	if ((flash->chip->total_size * 1024 > 512 * 1024)) {
		default_spi_read(flash, buf, start, len);
	} else {
		mmio_readn((void *)(flash->virtual_memory + start), buf, len);
	}

	return 0;
}

static int it8716f_spi_chip_write_256(struct flashctx *flash, const uint8_t *buf,
				      unsigned int start, unsigned int len)
{
	const struct flashchip *chip = flash->chip;
	/*
	 * IT8716F only allows maximum of 512 kb SPI chip size for memory
	 * mapped access. It also can't write more than 1+3+256 bytes at once,
	 * so page_size > 256 bytes needs a fallback.
	 * FIXME: Split too big page writes into chunks IT87* can handle instead
	 * of degrading to single-byte program.
	 * FIXME: Check if someone explicitly requested to use IT87 SPI although
	 * the mainboard does not use IT87 SPI translation. This should be done
	 * via a programmer parameter for the internal programmer.
	 */
	if ((chip->total_size * 1024 > 512 * 1024) || (chip->page_size > 256)) {
		spi_chip_write_1(flash, buf, start, len);
	} else {
		unsigned int lenhere;

		if (start % chip->page_size) {
			/* start to the end of the page or to start + len,
			 * whichever is smaller.
			 */
			lenhere = min(len, chip->page_size - start % chip->page_size);
			spi_chip_write_1(flash, buf, start, lenhere);
			start += lenhere;
			len -= lenhere;
			buf += lenhere;
		}

		while (len >= chip->page_size) {
			int ret = it8716f_spi_page_program(flash, buf, start);
			if (ret)
				return ret;
			update_progress(flash, FLASHROM_PROGRESS_WRITE, chip->page_size);
			start += chip->page_size;
			len -= chip->page_size;
			buf += chip->page_size;
		}
		if (len)
			spi_chip_write_1(flash, buf, start, len);
	}

	return 0;
}

static int it8716f_shutdown(void *data)
{
	free(data);
	return 0;
}

static const struct spi_master spi_master_it87xx = {
	.max_data_read	= 3,
	.max_data_write	= MAX_DATA_UNSPECIFIED,
	.command	= it8716f_spi_send_command,
	.map_flash_region	= physmap,
	.unmap_flash_region	= physunmap,
	.read		= it8716f_spi_chip_read,
	.write_256	= it8716f_spi_chip_write_256,
	.write_aai	= spi_chip_write_1,
	.shutdown	= it8716f_shutdown,
};

static uint16_t it87spi_probe(const struct programmer_cfg *cfg, uint16_t port)
{
	uint8_t tmp = 0;
	uint16_t flashport = 0;

	enter_conf_mode_ite(port);

	char *param = extract_programmer_param_str(cfg, "dualbiosindex");
	if (param != NULL) {
		sio_write(port, 0x07, 0x07); /* Select GPIO LDN */
		tmp = sio_read(port, 0xEF);
		if (*param == '\0') { /* Print current setting only. */
			free(param);
		} else {
			char *dualbiosindex_suffix;
			errno = 0;
			long chip_index = strtol(param, &dualbiosindex_suffix, 0);
			if (errno != 0 || *dualbiosindex_suffix != '\0' || chip_index < 0 || chip_index > 1) {
				msg_perr("DualBIOS: Invalid chip index requested - choose 0 or 1.\n");
				free(param);
				exit_conf_mode_ite(port);
				return 1;
			}
			free(param);
			if (chip_index != (tmp & 1)) {
				msg_pdbg("DualBIOS: Previous chip index: %d\n", tmp & 1);
				sio_write(port, 0xEF, (tmp & 0xFE) | chip_index);
				tmp = sio_read(port, 0xEF);
				if ((tmp & 1) != chip_index) {
					msg_perr("DualBIOS: Chip selection failed.\n");
					exit_conf_mode_ite(port);
					return 1;
				}
			}
		}
		msg_pinfo("DualBIOS: Selected chip: %d\n", tmp & 1);
	}

	/* NOLDN, reg 0x24, mask out lowest bit (suspend) */
	tmp = sio_read(port, 0x24) & 0xFE;
	/* Check if LPC->SPI translation is active. */
	if (!(tmp & 0x0e)) {
		msg_pdbg("No IT87* serial flash segment enabled.\n");
		exit_conf_mode_ite(port);
		/* Nothing to do. */
		return 0;
	}
	msg_pdbg("Serial flash segment 0x%08x-0x%08x %sabled\n",
		 0xFFFE0000, 0xFFFFFFFF, (tmp & 1 << 1) ? "en" : "dis");
	msg_pdbg("Serial flash segment 0x%08x-0x%08x %sabled\n",
		 0x000E0000, 0x000FFFFF, (tmp & 1 << 1) ? "en" : "dis");
	msg_pdbg("Serial flash segment 0x%08x-0x%08x %sabled\n",
		 0xFFEE0000, 0xFFEFFFFF, (tmp & 1 << 2) ? "en" : "dis");
	msg_pdbg("Serial flash segment 0x%08x-0x%08x %sabled\n",
		 0xFFF80000, 0xFFFEFFFF, (tmp & 1 << 3) ? "en" : "dis");
	msg_pdbg("LPC write to serial flash %sabled\n",
		 (tmp & 1 << 4) ? "en" : "dis");
	/* The LPC->SPI force write enable below only makes sense for
	 * non-programmer mode.
	 */
	/* If any serial flash segment is enabled, enable writing. */
	if ((tmp & 0xe) && (!(tmp & 1 << 4))) {
		msg_pdbg("Enabling LPC write to serial flash\n");
		tmp |= 1 << 4;
		sio_write(port, 0x24, tmp);
	}
	msg_pdbg("Serial flash pin %i\n", (tmp & 1 << 5) ? 87 : 29);
	/* LDN 0x7, reg 0x64/0x65 */
	sio_write(port, 0x07, 0x7);
	flashport = sio_read(port, 0x64) << 8;
	flashport |= sio_read(port, 0x65);
	msg_pdbg("Serial flash port 0x%04x\n", flashport);
	/* Non-default port requested? */
	param = extract_programmer_param_str(cfg, "it87spiport");
	if (param) {
		char *endptr = NULL;
		unsigned long forced_flashport;
		forced_flashport = strtoul(param, &endptr, 0);
		/* Port 0, port >0x1000, unaligned ports and garbage strings
		 * are rejected.
		 */
		if (!forced_flashport || (forced_flashport >= 0x1000) ||
		    (forced_flashport & 0x7) || (*endptr != '\0')) {
			/* Using ports below 0x100 is a really bad idea, and
			 * should only be done if no port between 0x100 and
			 * 0xff8 works due to routing issues.
			 */
			msg_perr("Error: it87spiport specified, but no valid "
				 "port specified.\nPort must be a multiple of "
				 "0x8 and lie between 0x100 and 0xff8.\n");
			exit_conf_mode_ite(port);
			free(param);
			return 1;
		} else {
			flashport = (uint16_t)forced_flashport;
			msg_pinfo("Forcing serial flash port 0x%04x\n",
				  flashport);
			sio_write(port, 0x64, (flashport >> 8));
			sio_write(port, 0x65, (flashport & 0xff));
		}
	}
	free(param);
	exit_conf_mode_ite(port);

	struct it8716f_spi_data *data = calloc(1, sizeof(*data));
	if (!data) {
		msg_perr("Unable to allocate space for extra SPI master data.\n");
		return SPI_GENERIC_ERROR;
	}

	data->flashport = flashport;
	data->fast_spi = true;

	if (internal_buses_supported & BUS_SPI)
		msg_pdbg("Overriding chipset SPI with IT87 SPI.\n");
	/* FIXME: Add the SPI bus or replace the other buses with it? */
	return register_spi_master(&spi_master_it87xx, data);
}

int init_superio_ite(const struct programmer_cfg *cfg)
{
	int i;
	int ret = 0;

	for (i = 0; i < superio_count; i++) {
		if (superios[i].vendor != SUPERIO_VENDOR_ITE)
			continue;

		switch (superios[i].model) {
		case 0x8705:
			ret |= it8705f_write_enable(superios[i].port);
			break;
		case 0x8686:
		case 0x8716:
		case 0x8718:
		case 0x8720:
		case 0x8728:
			ret |= it87spi_probe(cfg, superios[i].port);
			break;
		default:
			msg_pdbg2("Super I/O ID 0x%04hx is not on the list of flash-capable controllers.\n",
				  superios[i].model);
		}
	}
	return ret;
}
