/*
 * This file is part of the flashrom project.
 *
 * Copyright (C) 2007, 2008 Carl-Daniel Hailfinger
 * Copyright (C) 2008 Ronald Hoogenboom <ronald@zonnet.nl>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

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

#include <stdio.h>
#include <pci/pci.h>
#include <stdint.h>
#include <string.h>
#include "flash.h"
#include "spi.h"

#define ITE_SUPERIO_PORT1	0x2e
#define ITE_SUPERIO_PORT2	0x4e


uint16_t it8716f_flashport = 0;
/* use fast 33MHz SPI (<>0) or slow 16MHz (0) */
int fast_spi = 1;

/* Generic Super I/O helper functions */
uint8_t regval(uint16_t port, uint8_t reg)
{
	outb(reg, port);
	return inb(port + 1);
}

void regwrite(uint16_t port, uint8_t reg, uint8_t val)
{
	outb(reg, port);
	outb(val, port + 1);
}

/* Helper functions for most recent ITE IT87xx Super I/O chips */
#define CHIP_ID_BYTE1_REG	0x20
#define CHIP_ID_BYTE2_REG	0x21
static 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);
}

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

static uint16_t find_ite_spi_flash_port(uint16_t port)
{
	uint8_t tmp = 0;
	uint16_t id, flashport = 0;

	enter_conf_mode_ite(port);

	id = regval(port, CHIP_ID_BYTE1_REG) << 8;
	id |= regval(port, CHIP_ID_BYTE2_REG);

	/* TODO: Handle more IT87xx if they support flash translation */
	if (id == 0x8716) {
		/* NOLDN, reg 0x24, mask out lowest bit (suspend) */
		tmp = regval(port, 0x24) & 0xFE;
		printf("Serial flash segment 0x%08x-0x%08x %sabled\n",
			0xFFFE0000, 0xFFFFFFFF, (tmp & 1 << 1) ? "en" : "dis");
		printf("Serial flash segment 0x%08x-0x%08x %sabled\n",
			0x000E0000, 0x000FFFFF, (tmp & 1 << 1) ? "en" : "dis");
		printf("Serial flash segment 0x%08x-0x%08x %sabled\n",
			0xFFEE0000, 0xFFEFFFFF, (tmp & 1 << 2) ? "en" : "dis");
		printf("Serial flash segment 0x%08x-0x%08x %sabled\n",
			0xFFF80000, 0xFFFEFFFF, (tmp & 1 << 3) ? "en" : "dis");
		printf("LPC write to serial flash %sabled\n",
			(tmp & 1 << 4) ? "en" : "dis");
		/* If any serial flash segment is enabled, enable writing. */
		if ((tmp & 0xe) && (!(tmp & 1 << 4))) {
			printf("Enabling LPC write to serial flash\n");
			tmp |= 1 << 4;
			regwrite(port, 0x24, tmp);
		}
		printf("serial flash pin %i\n", (tmp & 1 << 5) ? 87 : 29);
		/* LDN 0x7, reg 0x64/0x65 */
		regwrite(port, 0x07, 0x7);
		flashport = regval(port, 0x64) << 8;
		flashport |= regval(port, 0x65);
	}
	exit_conf_mode_ite(port);
	return flashport;
}

int it87xx_probe_spi_flash(const char *name)
{
	it8716f_flashport = find_ite_spi_flash_port(ITE_SUPERIO_PORT1);
	if (!it8716f_flashport)
		it8716f_flashport = find_ite_spi_flash_port(ITE_SUPERIO_PORT2);
	return (!it8716f_flashport);
}

/* 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. */
int it8716f_spi_command(unsigned int writecnt, unsigned int readcnt, const unsigned char *writearr, unsigned char *readarr)
{
	uint8_t busy, writeenc;
	int i;

	do {
		busy = inb(it8716f_flashport) & 0x80;
	} while (busy);
	if (readcnt > 3) {
		printf("%s called with unsupported readcnt %i.\n",
			__FUNCTION__, readcnt);
		return 1;
	}
	switch (writecnt) {
	case 1:
		outb(writearr[0], it8716f_flashport + 1);
		writeenc = 0x0;
		break;
	case 2:
		outb(writearr[0], it8716f_flashport + 1);
		outb(writearr[1], it8716f_flashport + 7);
		writeenc = 0x1;
		break;
	case 4:
		outb(writearr[0], it8716f_flashport + 1);
		outb(writearr[1], it8716f_flashport + 4);
		outb(writearr[2], it8716f_flashport + 3);
		outb(writearr[3], it8716f_flashport + 2);
		writeenc = 0x2;
		break;
	case 5:
		outb(writearr[0], it8716f_flashport + 1);
		outb(writearr[1], it8716f_flashport + 4);
		outb(writearr[2], it8716f_flashport + 3);
		outb(writearr[3], it8716f_flashport + 2);
		outb(writearr[4], it8716f_flashport + 7);
		writeenc = 0x3;
		break;
	default:
		printf("%s called with unsupported writecnt %i.\n",
			__FUNCTION__, writecnt);
		return 1;
	}
	/* 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 + (fast_spi ? 1 : 0)) << 4) | ((readcnt & 0x3) << 2) | (writeenc), it8716f_flashport);

	if (readcnt > 0) {
		do {
			busy = inb(it8716f_flashport) & 0x80;
		} while (busy);

		for (i = 0; i < readcnt; i++) {
			readarr[i] = inb(it8716f_flashport + 5 + i);
		}
	}

	return 0;
}

/* Page size is usually 256 bytes */
void it8716f_spi_page_program(int block, uint8_t *buf, uint8_t *bios) {
	int i;

	spi_write_enable();
	outb(0x06 , it8716f_flashport + 1);
	outb(((2 + (fast_spi ? 1 : 0)) << 4), it8716f_flashport);
	for (i = 0; i < 256; i++) {
		bios[256 * block + i] = buf[256 * block + i];
	}
	outb(0, it8716f_flashport);
	/* Wait until the Write-In-Progress bit is cleared.
	 * This usually takes 1-10 ms, so wait in 1 ms steps.
	 */
	while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
		usleep(1000);
}

/*
 * IT8716F only allows maximum of 512 kb SPI mapped to LPC memory cycles
 * Program chip using firmware cycle byte programming. (SLOW!)
 */
int it8716f_over512k_spi_chip_write(struct flashchip *flash, uint8_t *buf)
{
	int total_size = 1024 * flash->total_size;
	int i;
	fast_spi = 0;

	spi_disable_blockprotect();
	for (i = 0; i < total_size; i++) {
		spi_write_enable();
		spi_byte_program(i, buf[i]);
		while (spi_read_status_register() & JEDEC_RDSR_BIT_WIP)
			myusec_delay(10);
	}
	/* resume normal ops... */
	outb(0x20, it8716f_flashport);
	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.
 */
int it8716f_spi_chip_read(struct flashchip *flash, uint8_t *buf)
{
	int total_size = 1024 * flash->total_size;
	int i;
	fast_spi = 0;

	if (total_size > 512 * 1024) {
		for (i = 0; i < total_size; i += 3) {
			int toread = 3;
			if (total_size - i < toread)
				toread = total_size - i;
			spi_nbyte_read(i, buf + i, toread);
		}
	} else {
		memcpy(buf, (const char *)flash->virtual_memory, total_size);
	}
	return 0;
}

int it8716f_spi_chip_write(struct flashchip *flash, uint8_t *buf) {
	int total_size = 1024 * flash->total_size;
	int i;
	if (total_size > 512 * 1024) {
		it8716f_over512k_spi_chip_write(flash, buf);
	} else {
		for (i = 0; i < total_size / 256; i++) {
			spi_page_program(i, buf, (uint8_t *)flash->virtual_memory);
		}
	}
	return 0;
}