// SPDX-License-Identifier: GPL-2.0

  /*
   * ifdtool - Manage Intel Firmware Descriptor information
   *
   * Copyright 2014 Google, Inc
   *

   * From Coreboot project, but it got a serious code clean-up
   * and a few new features
   */
  
  #include <assert.h>
  #include <fcntl.h>
  #include <getopt.h>

  #include <stdbool.h>

  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
  #include <unistd.h>
  #include <sys/types.h>
  #include <sys/stat.h>

  #include <linux/libfdt.h>

  #include "ifdtool.h"
  
  #undef DEBUG
  
  #ifdef DEBUG
  #define debug(fmt, args...)	printf(fmt, ##args)
  #else
  #define debug(fmt, args...)
  #endif
  
  #define FD_SIGNATURE		0x0FF0A55A
  #define FLREG_BASE(reg)		((reg & 0x00000fff) << 12);
  #define FLREG_LIMIT(reg)	(((reg & 0x0fff0000) >> 4) | 0xfff);

  struct input_file {
  	char *fname;
  	unsigned int addr;

  };

  /**
   * find_fd() - Find the flash description in the ROM image
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   * @return pointer to structure, or NULL if not found
   */
  static struct fdbar_t *find_fd(char *image, int size)
  {
  	uint32_t *ptr, *end;
  
  	/* Scan for FD signature */
  	for (ptr = (uint32_t *)image, end = ptr + size / 4; ptr < end; ptr++) {
  		if (*ptr == FD_SIGNATURE)
  			break;
  	}
  
  	if (ptr == end) {
  		printf("No Flash Descriptor found in this image
  ");
  		return NULL;
  	}

  	debug("Found Flash Descriptor signature at 0x%08lx
  ",
  	      (char *)ptr - image);

  
  	return (struct fdbar_t *)ptr;
  }
  
  /**
   * get_region() - Get information about the selected region
   *
   * @frba:		Flash region list
   * @region_type:	Type of region (0..MAX_REGIONS-1)
   * @region:		Region information is written here
   * @return 0 if OK, else -ve
   */
  static int get_region(struct frba_t *frba, int region_type,
  		      struct region_t *region)
  {
  	if (region_type >= MAX_REGIONS) {
  		fprintf(stderr, "Invalid region type.
  ");
  		return -1;
  	}
  
  	region->base = FLREG_BASE(frba->flreg[region_type]);
  	region->limit = FLREG_LIMIT(frba->flreg[region_type]);
  	region->size = region->limit - region->base + 1;
  
  	return 0;
  }
  
  static const char *region_name(int region_type)
  {
  	static const char *const regions[] = {
  		"Flash Descriptor",
  		"BIOS",
  		"Intel ME",
  		"GbE",
  		"Platform Data"
  	};
  
  	assert(region_type < MAX_REGIONS);
  
  	return regions[region_type];
  }
  
  static const char *region_filename(int region_type)
  {
  	static const char *const region_filenames[] = {
  		"flashregion_0_flashdescriptor.bin",
  		"flashregion_1_bios.bin",
  		"flashregion_2_intel_me.bin",
  		"flashregion_3_gbe.bin",
  		"flashregion_4_platform_data.bin"
  	};
  
  	assert(region_type < MAX_REGIONS);
  
  	return region_filenames[region_type];
  }
  
  static int dump_region(int num, struct frba_t *frba)
  {
  	struct region_t region;
  	int ret;
  
  	ret = get_region(frba, num, &region);
  	if (ret)
  		return ret;
  
  	printf("  Flash Region %d (%s): %08x - %08x %s
  ",
  	       num, region_name(num), region.base, region.limit,
  	       region.size < 1 ? "(unused)" : "");
  
  	return ret;
  }
  
  static void dump_frba(struct frba_t *frba)
  {
  	int i;
  
  	printf("Found Region Section
  ");
  	for (i = 0; i < MAX_REGIONS; i++) {
  		printf("FLREG%d:    0x%08x
  ", i, frba->flreg[i]);
  		dump_region(i, frba);
  	}
  }
  
  static void decode_spi_frequency(unsigned int freq)
  {
  	switch (freq) {
  	case SPI_FREQUENCY_20MHZ:
  		printf("20MHz");
  		break;
  	case SPI_FREQUENCY_33MHZ:
  		printf("33MHz");
  		break;
  	case SPI_FREQUENCY_50MHZ:
  		printf("50MHz");
  		break;
  	default:
  		printf("unknown<%x>MHz", freq);
  	}
  }
  
  static void decode_component_density(unsigned int density)
  {
  	switch (density) {
  	case COMPONENT_DENSITY_512KB:
  		printf("512KiB");
  		break;
  	case COMPONENT_DENSITY_1MB:
  		printf("1MiB");
  		break;
  	case COMPONENT_DENSITY_2MB:
  		printf("2MiB");
  		break;
  	case COMPONENT_DENSITY_4MB:
  		printf("4MiB");
  		break;
  	case COMPONENT_DENSITY_8MB:
  		printf("8MiB");
  		break;
  	case COMPONENT_DENSITY_16MB:
  		printf("16MiB");
  		break;
  	default:
  		printf("unknown<%x>MiB", density);
  	}
  }
  
  static void dump_fcba(struct fcba_t *fcba)
  {
  	printf("
  Found Component Section
  ");
  	printf("FLCOMP     0x%08x
  ", fcba->flcomp);
  	printf("  Dual Output Fast Read Support:       %ssupported
  ",
  	       (fcba->flcomp & (1 << 30)) ? "" : "not ");
  	printf("  Read ID/Read Status Clock Frequency: ");
  	decode_spi_frequency((fcba->flcomp >> 27) & 7);
  	printf("
    Write/Erase Clock Frequency:         ");
  	decode_spi_frequency((fcba->flcomp >> 24) & 7);
  	printf("
    Fast Read Clock Frequency:           ");
  	decode_spi_frequency((fcba->flcomp >> 21) & 7);
  	printf("
    Fast Read Support:                   %ssupported",
  	       (fcba->flcomp & (1 << 20)) ? "" : "not ");
  	printf("
    Read Clock Frequency:                ");
  	decode_spi_frequency((fcba->flcomp >> 17) & 7);
  	printf("
    Component 2 Density:                 ");
  	decode_component_density((fcba->flcomp >> 3) & 7);
  	printf("
    Component 1 Density:                 ");
  	decode_component_density(fcba->flcomp & 7);
  	printf("
  ");
  	printf("FLILL      0x%08x
  ", fcba->flill);
  	printf("  Invalid Instruction 3: 0x%02x
  ",
  	       (fcba->flill >> 24) & 0xff);
  	printf("  Invalid Instruction 2: 0x%02x
  ",
  	       (fcba->flill >> 16) & 0xff);
  	printf("  Invalid Instruction 1: 0x%02x
  ",
  	       (fcba->flill >> 8) & 0xff);
  	printf("  Invalid Instruction 0: 0x%02x
  ",
  	       fcba->flill & 0xff);
  	printf("FLPB       0x%08x
  ", fcba->flpb);
  	printf("  Flash Partition Boundary Address: 0x%06x
  
  ",
  	       (fcba->flpb & 0xfff) << 12);
  }
  
  static void dump_fpsba(struct fpsba_t *fpsba)
  {
  	int i;
  
  	printf("Found PCH Strap Section
  ");
  	for (i = 0; i < MAX_STRAPS; i++)
  		printf("PCHSTRP%-2d:  0x%08x
  ", i, fpsba->pchstrp[i]);
  }
  
  static const char *get_enabled(int flag)
  {
  	return flag ? "enabled" : "disabled";
  }
  
  static void decode_flmstr(uint32_t flmstr)
  {
  	printf("  Platform Data Region Write Access: %s
  ",
  	       get_enabled(flmstr & (1 << 28)));
  	printf("  GbE Region Write Access:           %s
  ",
  	       get_enabled(flmstr & (1 << 27)));
  	printf("  Intel ME Region Write Access:      %s
  ",
  	       get_enabled(flmstr & (1 << 26)));
  	printf("  Host CPU/BIOS Region Write Access: %s
  ",
  	       get_enabled(flmstr & (1 << 25)));
  	printf("  Flash Descriptor Write Access:     %s
  ",
  	       get_enabled(flmstr & (1 << 24)));
  
  	printf("  Platform Data Region Read Access:  %s
  ",
  	       get_enabled(flmstr & (1 << 20)));
  	printf("  GbE Region Read Access:            %s
  ",
  	       get_enabled(flmstr & (1 << 19)));
  	printf("  Intel ME Region Read Access:       %s
  ",
  	       get_enabled(flmstr & (1 << 18)));
  	printf("  Host CPU/BIOS Region Read Access:  %s
  ",
  	       get_enabled(flmstr & (1 << 17)));
  	printf("  Flash Descriptor Read Access:      %s
  ",
  	       get_enabled(flmstr & (1 << 16)));
  
  	printf("  Requester ID:                      0x%04x
  
  ",
  	       flmstr & 0xffff);
  }
  
  static void dump_fmba(struct fmba_t *fmba)
  {
  	printf("Found Master Section
  ");
  	printf("FLMSTR1:   0x%08x (Host CPU/BIOS)
  ", fmba->flmstr1);
  	decode_flmstr(fmba->flmstr1);
  	printf("FLMSTR2:   0x%08x (Intel ME)
  ", fmba->flmstr2);
  	decode_flmstr(fmba->flmstr2);
  	printf("FLMSTR3:   0x%08x (GbE)
  ", fmba->flmstr3);
  	decode_flmstr(fmba->flmstr3);
  }
  
  static void dump_fmsba(struct fmsba_t *fmsba)
  {
  	int i;
  
  	printf("Found Processor Strap Section
  ");
  	for (i = 0; i < 4; i++)
  		printf("????:      0x%08x
  ", fmsba->data[0]);
  }
  
  static void dump_jid(uint32_t jid)
  {
  	printf("    SPI Component Device ID 1:          0x%02x
  ",
  	       (jid >> 16) & 0xff);
  	printf("    SPI Component Device ID 0:          0x%02x
  ",
  	       (jid >> 8) & 0xff);
  	printf("    SPI Component Vendor ID:            0x%02x
  ",
  	       jid & 0xff);
  }
  
  static void dump_vscc(uint32_t vscc)
  {
  	printf("    Lower Erase Opcode:                 0x%02x
  ",
  	       vscc >> 24);
  	printf("    Lower Write Enable on Write Status: 0x%02x
  ",
  	       vscc & (1 << 20) ? 0x06 : 0x50);
  	printf("    Lower Write Status Required:        %s
  ",
  	       vscc & (1 << 19) ? "Yes" : "No");
  	printf("    Lower Write Granularity:            %d bytes
  ",
  	       vscc & (1 << 18) ? 64 : 1);
  	printf("    Lower Block / Sector Erase Size:    ");
  	switch ((vscc >> 16) & 0x3) {
  	case 0:
  		printf("256 Byte
  ");
  		break;
  	case 1:
  		printf("4KB
  ");
  		break;
  	case 2:
  		printf("8KB
  ");
  		break;
  	case 3:
  		printf("64KB
  ");
  		break;
  	}
  
  	printf("    Upper Erase Opcode:                 0x%02x
  ",
  	       (vscc >> 8) & 0xff);
  	printf("    Upper Write Enable on Write Status: 0x%02x
  ",
  	       vscc & (1 << 4) ? 0x06 : 0x50);
  	printf("    Upper Write Status Required:        %s
  ",
  	       vscc & (1 << 3) ? "Yes" : "No");
  	printf("    Upper Write Granularity:            %d bytes
  ",
  	       vscc & (1 << 2) ? 64 : 1);
  	printf("    Upper Block / Sector Erase Size:    ");
  	switch (vscc & 0x3) {
  	case 0:
  		printf("256 Byte
  ");
  		break;
  	case 1:
  		printf("4KB
  ");
  		break;
  	case 2:
  		printf("8KB
  ");
  		break;
  	case 3:
  		printf("64KB
  ");
  		break;
  	}
  }
  
  static void dump_vtba(struct vtba_t *vtba, int vtl)
  {
  	int i;
  	int num = (vtl >> 1) < 8 ? (vtl >> 1) : 8;
  
  	printf("ME VSCC table:
  ");
  	for (i = 0; i < num; i++) {
  		printf("  JID%d:  0x%08x
  ", i, vtba->entry[i].jid);
  		dump_jid(vtba->entry[i].jid);
  		printf("  VSCC%d: 0x%08x
  ", i, vtba->entry[i].vscc);
  		dump_vscc(vtba->entry[i].vscc);
  	}
  	printf("
  ");
  }
  
  static void dump_oem(uint8_t *oem)
  {
  	int i, j;
  	printf("OEM Section:
  ");
  	for (i = 0; i < 4; i++) {
  		printf("%02x:", i << 4);
  		for (j = 0; j < 16; j++)
  			printf(" %02x", oem[(i<<4)+j]);
  		printf("
  ");
  	}
  	printf("
  ");
  }
  
  /**
   * dump_fd() - Display a dump of the full flash description
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   * @return 0 if OK, -1 on error
   */
  static int dump_fd(char *image, int size)
  {
  	struct fdbar_t *fdb = find_fd(image, size);
  
  	if (!fdb)
  		return -1;
  
  	printf("FLMAP0:    0x%08x
  ", fdb->flmap0);
  	printf("  NR:      %d
  ", (fdb->flmap0 >> 24) & 7);
  	printf("  FRBA:    0x%x
  ", ((fdb->flmap0 >> 16) & 0xff) << 4);
  	printf("  NC:      %d
  ", ((fdb->flmap0 >> 8) & 3) + 1);
  	printf("  FCBA:    0x%x
  ", ((fdb->flmap0) & 0xff) << 4);
  
  	printf("FLMAP1:    0x%08x
  ", fdb->flmap1);
  	printf("  ISL:     0x%02x
  ", (fdb->flmap1 >> 24) & 0xff);
  	printf("  FPSBA:   0x%x
  ", ((fdb->flmap1 >> 16) & 0xff) << 4);
  	printf("  NM:      %d
  ", (fdb->flmap1 >> 8) & 3);
  	printf("  FMBA:    0x%x
  ", ((fdb->flmap1) & 0xff) << 4);
  
  	printf("FLMAP2:    0x%08x
  ", fdb->flmap2);
  	printf("  PSL:     0x%04x
  ", (fdb->flmap2 >> 8) & 0xffff);
  	printf("  FMSBA:   0x%x
  ", ((fdb->flmap2) & 0xff) << 4);
  
  	printf("FLUMAP1:   0x%08x
  ", fdb->flumap1);
  	printf("  Intel ME VSCC Table Length (VTL):        %d
  ",
  	       (fdb->flumap1 >> 8) & 0xff);
  	printf("  Intel ME VSCC Table Base Address (VTBA): 0x%06x
  
  ",
  	       (fdb->flumap1 & 0xff) << 4);
  	dump_vtba((struct vtba_t *)
  			(image + ((fdb->flumap1 & 0xff) << 4)),
  			(fdb->flumap1 >> 8) & 0xff);
  	dump_oem((uint8_t *)image + 0xf00);
  	dump_frba((struct frba_t *)(image + (((fdb->flmap0 >> 16) & 0xff)
  			<< 4)));
  	dump_fcba((struct fcba_t *)(image + (((fdb->flmap0) & 0xff) << 4)));
  	dump_fpsba((struct fpsba_t *)
  			(image + (((fdb->flmap1 >> 16) & 0xff) << 4)));
  	dump_fmba((struct fmba_t *)(image + (((fdb->flmap1) & 0xff) << 4)));
  	dump_fmsba((struct fmsba_t *)(image + (((fdb->flmap2) & 0xff) << 4)));
  
  	return 0;
  }
  
  /**
   * write_regions() - Write each region from an image to its own file
   *
   * The filename to use in each case is fixed - see region_filename()
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   * @return 0 if OK, -ve on error
   */
  static int write_regions(char *image, int size)
  {
  	struct fdbar_t *fdb;
  	struct frba_t *frba;
  	int ret = 0;
  	int i;
  
  	fdb =  find_fd(image, size);
  	if (!fdb)
  		return -1;
  
  	frba = (struct frba_t *)(image + (((fdb->flmap0 >> 16) & 0xff) << 4));
  
  	for (i = 0; i < MAX_REGIONS; i++) {
  		struct region_t region;
  		int region_fd;
  
  		ret = get_region(frba, i, &region);
  		if (ret)
  			return ret;
  		dump_region(i, frba);

  		if (region.size <= 0)

  			continue;
  		region_fd = open(region_filename(i),
  				 O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR |
  				 S_IWUSR | S_IRGRP | S_IROTH);
  		if (write(region_fd, image + region.base, region.size) !=
  				region.size) {
  			perror("Error while writing");
  			ret = -1;
  		}
  		close(region_fd);
  	}
  
  	return ret;
  }

  static int perror_fname(const char *fmt, const char *fname)
  {
  	char msg[strlen(fmt) + strlen(fname) + 1];
  
  	sprintf(msg, fmt, fname);
  	perror(msg);
  
  	return -1;
  }

  /**
   * write_image() - Write the image to a file
   *
   * @filename:	Filename to use for the image
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   * @return 0 if OK, -ve on error
   */
  static int write_image(char *filename, char *image, int size)
  {
  	int new_fd;
  
  	debug("Writing new image to %s
  ", filename);
  
  	new_fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR |
  		      S_IWUSR | S_IRGRP | S_IROTH);

  	if (new_fd < 0)
  		return perror_fname("Could not open file '%s'", filename);
  	if (write(new_fd, image, size) != size)
  		return perror_fname("Could not write file '%s'", filename);

  	close(new_fd);
  
  	return 0;
  }
  
  /**
   * set_spi_frequency() - Set the SPI frequency to use when booting
   *
   * Several frequencies are supported, some of which work with fast devices.
   * For SPI emulators, the slowest (SPI_FREQUENCY_20MHZ) is often used. The
   * Intel boot system uses this information somehow on boot.
   *
   * The image is updated with the supplied value
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   * @freq:	SPI frequency to use
   */
  static void set_spi_frequency(char *image, int size, enum spi_frequency freq)
  {
  	struct fdbar_t *fdb = find_fd(image, size);
  	struct fcba_t *fcba;
  
  	fcba = (struct fcba_t *)(image + (((fdb->flmap0) & 0xff) << 4));
  
  	/* clear bits 21-29 */
  	fcba->flcomp &= ~0x3fe00000;
  	/* Read ID and Read Status Clock Frequency */
  	fcba->flcomp |= freq << 27;
  	/* Write and Erase Clock Frequency */
  	fcba->flcomp |= freq << 24;
  	/* Fast Read Clock Frequency */
  	fcba->flcomp |= freq << 21;
  }
  
  /**
   * set_em100_mode() - Set a SPI frequency that will work with Dediprog EM100
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   */
  static void set_em100_mode(char *image, int size)
  {
  	struct fdbar_t *fdb = find_fd(image, size);
  	struct fcba_t *fcba;
  
  	fcba = (struct fcba_t *)(image + (((fdb->flmap0) & 0xff) << 4));
  	fcba->flcomp &= ~(1 << 30);
  	set_spi_frequency(image, size, SPI_FREQUENCY_20MHZ);
  }
  
  /**
   * lock_descriptor() - Lock the NE descriptor so it cannot be updated
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   */
  static void lock_descriptor(char *image, int size)
  {
  	struct fdbar_t *fdb = find_fd(image, size);
  	struct fmba_t *fmba;
  
  	/*
  	 * TODO: Dynamically take Platform Data Region and GbE Region into
  	 * account.
  	 */
  	fmba = (struct fmba_t *)(image + (((fdb->flmap1) & 0xff) << 4));
  	fmba->flmstr1 = 0x0a0b0000;
  	fmba->flmstr2 = 0x0c0d0000;
  	fmba->flmstr3 = 0x08080118;
  }
  
  /**
   * unlock_descriptor() - Lock the NE descriptor so it can be updated
   *
   * @image:	Pointer to image
   * @size:	Size of image in bytes
   */
  static void unlock_descriptor(char *image, int size)
  {
  	struct fdbar_t *fdb = find_fd(image, size);
  	struct fmba_t *fmba;
  
  	fmba = (struct fmba_t *)(image + (((fdb->flmap1) & 0xff) << 4));
  	fmba->flmstr1 = 0xffff0000;
  	fmba->flmstr2 = 0xffff0000;
  	fmba->flmstr3 = 0x08080118;
  }
  
  /**
   * open_for_read() - Open a file for reading
   *
   * @fname:	Filename to open
   * @sizep:	Returns file size in bytes
   * @return 0 if OK, -1 on error
   */
  int open_for_read(const char *fname, int *sizep)
  {
  	int fd = open(fname, O_RDONLY);
  	struct stat buf;

  	if (fd == -1)
  		return perror_fname("Could not open file '%s'", fname);
  	if (fstat(fd, &buf) == -1)
  		return perror_fname("Could not stat file '%s'", fname);

  	*sizep = buf.st_size;
  	debug("File %s is %d bytes
  ", fname, *sizep);
  
  	return fd;
  }
  
  /**
   * inject_region() - Add a file to an image region
   *
   * This puts a file into a particular region of the flash. Several pre-defined
   * regions are used.
   *
   * @image:		Pointer to image
   * @size:		Size of image in bytes
   * @region_type:	Region where the file should be added
   * @region_fname:	Filename to add to the image
   * @return 0 if OK, -ve on error
   */
  int inject_region(char *image, int size, int region_type, char *region_fname)
  {
  	struct fdbar_t *fdb = find_fd(image, size);
  	struct region_t region;
  	struct frba_t *frba;
  	int region_size;
  	int offset = 0;
  	int region_fd;
  	int ret;
  
  	if (!fdb)
  		exit(EXIT_FAILURE);
  	frba = (struct frba_t *)(image + (((fdb->flmap0 >> 16) & 0xff) << 4));
  
  	ret = get_region(frba, region_type, &region);
  	if (ret)
  		return -1;
  	if (region.size <= 0xfff) {
  		fprintf(stderr, "Region %s is disabled in target. Not injecting.
  ",
  			region_name(region_type));
  		return -1;
  	}
  
  	region_fd = open_for_read(region_fname, &region_size);
  	if (region_fd < 0)
  		return region_fd;
  
  	if ((region_size > region.size) ||
  	    ((region_type != 1) && (region_size > region.size))) {
  		fprintf(stderr, "Region %s is %d(0x%x) bytes. File is %d(0x%x)  bytes. Not injecting.
  ",
  			region_name(region_type), region.size,
  			region.size, region_size, region_size);
  		return -1;
  	}
  
  	if ((region_type == 1) && (region_size < region.size)) {
  		fprintf(stderr, "Region %s is %d(0x%x) bytes. File is %d(0x%x) bytes. Padding before injecting.
  ",
  			region_name(region_type), region.size,
  			region.size, region_size, region_size);
  		offset = region.size - region_size;
  		memset(image + region.base, 0xff, offset);
  	}
  
  	if (size < region.base + offset + region_size) {
  		fprintf(stderr, "Output file is too small. (%d < %d)
  ",
  			size, region.base + offset + region_size);
  		return -1;
  	}
  
  	if (read(region_fd, image + region.base + offset, region_size)
  							!= region_size) {
  		perror("Could not read file");
  		return -1;
  	}
  
  	close(region_fd);
  
  	debug("Adding %s as the %s section
  ", region_fname,
  	      region_name(region_type));
  
  	return 0;
  }
  
  /**
   * write_data() - Write some raw data into a region
   *
   * This puts a file into a particular place in the flash, ignoring the
   * regions. Be careful not to overwrite something important.
   *
   * @image:		Pointer to image
   * @size:		Size of image in bytes
   * @addr:		x86 ROM address to put file. The ROM ends at
   *			0xffffffff so use an address relative to that. For an
   *			8MB ROM the start address is 0xfff80000.
   * @write_fname:	Filename to add to the image

   * @offset_uboot_top:	Offset of the top of U-Boot

   * @offset_uboot_start:	Offset of the start of U-Boot

   * @return number of bytes written if OK, -ve on error

   */
  static int write_data(char *image, int size, unsigned int addr,

  		      const char *write_fname, int offset_uboot_top,
  		      int offset_uboot_start)

  {
  	int write_fd, write_size;
  	int offset;
  
  	write_fd = open_for_read(write_fname, &write_size);
  	if (write_fd < 0)
  		return write_fd;

  	offset = (uint32_t)(addr + size);

  	if (offset_uboot_top) {
  		if (offset_uboot_start < offset &&
  		    offset_uboot_top >= offset) {
  			fprintf(stderr, "U-Boot image overlaps with region '%s'
  ",
  				write_fname);
  			fprintf(stderr,
  				"U-Boot finishes at offset %x, file starts at %x
  ",
  				offset_uboot_top, offset);
  			return -EXDEV;
  		}
  		if (offset_uboot_start > offset &&
  		    offset_uboot_start <= offset + write_size) {
  			fprintf(stderr, "U-Boot image overlaps with region '%s'
  ",
  				write_fname);
  			fprintf(stderr,
  				"U-Boot starts at offset %x, file finishes at %x
  ",
  				offset_uboot_start, offset + write_size);
  			return -EXDEV;
  		}

  	}

  	debug("Writing %s to offset %#x
  ", write_fname, offset);
  
  	if (offset < 0 || offset + write_size > size) {
  		fprintf(stderr, "Output file is too small. (%d < %d)
  ",
  			size, offset + write_size);
  		return -1;
  	}
  
  	if (read(write_fd, image + offset, write_size) != write_size) {
  		perror("Could not read file");
  		return -1;
  	}
  
  	close(write_fd);

  	return write_size;
  }

  static void print_version(void)
  {
  	printf("ifdtool v%s -- ", IFDTOOL_VERSION);
  	printf("Copyright (C) 2014 Google Inc.
  
  ");

  	printf("SPDX-License-Identifier: GPL-2.0+
  ");

  }
  
  static void print_usage(const char *name)
  {
  	printf("usage: %s [-vhdix?] <filename> [<outfile>]
  ", name);
  	printf("
  "
  	       "   -d | --dump:                      dump intel firmware descriptor
  "
  	       "   -x | --extract:                   extract intel fd modules
  "
  	       "   -i | --inject <region>:<module>   inject file <module> into region <region>
  "
  	       "   -w | --write <addr>:<file>        write file to appear at memory address <addr>
  "

  	       "                                     multiple files can be written simultaneously
  "

  	       "   -s | --spifreq <20|33|50>         set the SPI frequency
  "
  	       "   -e | --em100                      set SPI frequency to 20MHz and disable
  "
  	       "                                     Dual Output Fast Read Support
  "
  	       "   -l | --lock                       Lock firmware descriptor and ME region
  "
  	       "   -u | --unlock                     Unlock firmware descriptor and ME region
  "
  	       "   -r | --romsize                    Specify ROM size
  "
  	       "   -D | --write-descriptor <file>    Write descriptor at base
  "
  	       "   -c | --create                     Create a new empty image
  "
  	       "   -v | --version:                   print the version
  "
  	       "   -h | --help:                      print this help
  
  "
  	       "<region> is one of Descriptor, BIOS, ME, GbE, Platform
  "
  	       "
  ");
  }
  
  /**
   * get_two_words() - Convert a string into two words separated by :
   *
   * The supplied string is split at ':', two substrings are allocated and
   * returned.
   *
   * @str:	String to split
   * @firstp:	Returns first string
   * @secondp:	Returns second string
   * @return 0 if OK, -ve if @str does not have a :
   */
  static int get_two_words(const char *str, char **firstp, char **secondp)
  {
  	const char *p;
  
  	p = strchr(str, ':');
  	if (!p)
  		return -1;
  	*firstp = strdup(str);
  	(*firstp)[p - str] = '\0';
  	*secondp = strdup(p + 1);
  
  	return 0;
  }
  
  int main(int argc, char *argv[])
  {
  	int opt, option_index = 0;
  	int mode_dump = 0, mode_extract = 0, mode_inject = 0;
  	int mode_spifreq = 0, mode_em100 = 0, mode_locked = 0;
  	int mode_unlocked = 0, mode_write = 0, mode_write_descriptor = 0;

  	int create = 0;

  	char *region_type_string = NULL, *inject_fname = NULL;
  	char *desc_fname = NULL, *addr_str = NULL;

  	int region_type = -1, inputfreq = 0;
  	enum spi_frequency spifreq = SPI_FREQUENCY_20MHZ;

  	struct input_file input_file[WRITE_MAX], *ifile, *fdt = NULL;

  	unsigned char wr_idx, wr_num = 0;

  	int rom_size = -1;
  	bool write_it;
  	char *filename;
  	char *outfile = NULL;
  	struct stat buf;
  	int size = 0;

  	bool have_uboot = false;

  	int bios_fd;
  	char *image;
  	int ret;
  	static struct option long_options[] = {
  		{"create", 0, NULL, 'c'},
  		{"dump", 0, NULL, 'd'},
  		{"descriptor", 1, NULL, 'D'},
  		{"em100", 0, NULL, 'e'},
  		{"extract", 0, NULL, 'x'},

  		{"fdt", 1, NULL, 'f'},

  		{"inject", 1, NULL, 'i'},
  		{"lock", 0, NULL, 'l'},
  		{"romsize", 1, NULL, 'r'},
  		{"spifreq", 1, NULL, 's'},
  		{"unlock", 0, NULL, 'u'},

  		{"uboot", 1, NULL, 'U'},

  		{"write", 1, NULL, 'w'},
  		{"version", 0, NULL, 'v'},
  		{"help", 0, NULL, 'h'},
  		{0, 0, 0, 0}
  	};

  	while ((opt = getopt_long(argc, argv, "cdD:ef:hi:lr:s:uU:vw:x?",

  				  long_options, &option_index)) != EOF) {
  		switch (opt) {
  		case 'c':
  			create = 1;
  			break;
  		case 'd':
  			mode_dump = 1;
  			break;
  		case 'D':
  			mode_write_descriptor = 1;

  			desc_fname = optarg;

  			break;
  		case 'e':
  			mode_em100 = 1;
  			break;
  		case 'i':
  			if (get_two_words(optarg, &region_type_string,

  					  &inject_fname)) {

  				print_usage(argv[0]);
  				exit(EXIT_FAILURE);
  			}
  			if (!strcasecmp("Descriptor", region_type_string))
  				region_type = 0;
  			else if (!strcasecmp("BIOS", region_type_string))
  				region_type = 1;
  			else if (!strcasecmp("ME", region_type_string))
  				region_type = 2;
  			else if (!strcasecmp("GbE", region_type_string))
  				region_type = 3;
  			else if (!strcasecmp("Platform", region_type_string))
  				region_type = 4;
  			if (region_type == -1) {
  				fprintf(stderr, "No such region type: '%s'
  
  ",
  					region_type_string);
  				print_usage(argv[0]);
  				exit(EXIT_FAILURE);
  			}
  			mode_inject = 1;
  			break;
  		case 'l':
  			mode_locked = 1;
  			break;
  		case 'r':
  			rom_size = strtol(optarg, NULL, 0);
  			debug("ROM size %d
  ", rom_size);
  			break;
  		case 's':
  			/* Parse the requested SPI frequency */
  			inputfreq = strtol(optarg, NULL, 0);
  			switch (inputfreq) {
  			case 20:
  				spifreq = SPI_FREQUENCY_20MHZ;
  				break;
  			case 33:
  				spifreq = SPI_FREQUENCY_33MHZ;
  				break;
  			case 50:
  				spifreq = SPI_FREQUENCY_50MHZ;
  				break;
  			default:
  				fprintf(stderr, "Invalid SPI Frequency: %d
  ",
  					inputfreq);
  				print_usage(argv[0]);
  				exit(EXIT_FAILURE);
  			}
  			mode_spifreq = 1;
  			break;
  		case 'u':
  			mode_unlocked = 1;
  			break;
  		case 'v':
  			print_version();
  			exit(EXIT_SUCCESS);
  			break;
  		case 'w':

  		case 'U':
  		case 'f':

  			ifile = &input_file[wr_num];

  			mode_write = 1;

  			if (wr_num < WRITE_MAX) {
  				if (get_two_words(optarg, &addr_str,

  						  &ifile->fname)) {

  					print_usage(argv[0]);
  					exit(EXIT_FAILURE);
  				}

  				ifile->addr = strtoll(optarg, NULL, 0);

  				wr_num++;
  			} else {
  				fprintf(stderr,
  					"The number of files to write simultaneously exceeds the limitation (%d)
  ",
  					WRITE_MAX);

  			}

  			break;
  		case 'x':
  			mode_extract = 1;
  			break;
  		case 'h':
  		case '?':
  		default:
  			print_usage(argv[0]);
  			exit(EXIT_SUCCESS);
  			break;
  		}
  	}
  
  	if (mode_locked == 1 && mode_unlocked == 1) {
  		fprintf(stderr, "Locking/Unlocking FD and ME are mutually exclusive
  ");
  		exit(EXIT_FAILURE);
  	}
  
  	if (mode_inject == 1 && mode_write == 1) {
  		fprintf(stderr, "Inject/Write are mutually exclusive
  ");
  		exit(EXIT_FAILURE);
  	}
  
  	if ((mode_dump + mode_extract + mode_inject +
  		(mode_spifreq | mode_em100 | mode_unlocked |
  		 mode_locked)) > 1) {
  		fprintf(stderr, "You may not specify more than one mode.
  
  ");
  		print_usage(argv[0]);
  		exit(EXIT_FAILURE);
  	}
  
  	if ((mode_dump + mode_extract + mode_inject + mode_spifreq +
  	     mode_em100 + mode_locked + mode_unlocked + mode_write +

  	     mode_write_descriptor) == 0 && !create) {

  		fprintf(stderr, "You need to specify a mode.
  
  ");
  		print_usage(argv[0]);
  		exit(EXIT_FAILURE);
  	}
  
  	if (create && rom_size == -1) {
  		fprintf(stderr, "You need to specify a rom size when creating.
  
  ");
  		exit(EXIT_FAILURE);
  	}
  
  	if (optind + 1 != argc) {
  		fprintf(stderr, "You need to specify a file.
  
  ");
  		print_usage(argv[0]);
  		exit(EXIT_FAILURE);
  	}

  	if (have_uboot && !fdt) {
  		fprintf(stderr,
  			"You must supply a device tree file for U-Boot
  
  ");
  		print_usage(argv[0]);
  		exit(EXIT_FAILURE);
  	}

  	filename = argv[optind];
  	if (optind + 2 != argc)
  		outfile = argv[optind + 1];
  
  	if (create)
  		bios_fd = open(filename, O_WRONLY | O_CREAT, 0666);
  	else
  		bios_fd = open(filename, outfile ? O_RDONLY : O_RDWR);
  
  	if (bios_fd == -1) {
  		perror("Could not open file");
  		exit(EXIT_FAILURE);
  	}
  
  	if (!create) {
  		if (fstat(bios_fd, &buf) == -1) {
  			perror("Could not stat file");
  			exit(EXIT_FAILURE);
  		}
  		size = buf.st_size;
  	}
  
  	debug("File %s is %d bytes
  ", filename, size);
  
  	if (rom_size == -1)
  		rom_size = size;
  
  	image = malloc(rom_size);
  	if (!image) {
  		printf("Out of memory.
  ");
  		exit(EXIT_FAILURE);
  	}
  
  	memset(image, '\xff', rom_size);
  	if (!create && read(bios_fd, image, size) != size) {
  		perror("Could not read file");
  		exit(EXIT_FAILURE);
  	}
  	if (size != rom_size) {
  		debug("ROM size changed to %d bytes
  ", rom_size);
  		size = rom_size;
  	}
  
  	write_it = true;
  	ret = 0;
  	if (mode_dump) {
  		ret = dump_fd(image, size);
  		write_it = false;
  	}
  
  	if (mode_extract) {
  		ret = write_regions(image, size);
  		write_it = false;
  	}
  
  	if (mode_write_descriptor)

  		ret = write_data(image, size, -size, desc_fname, 0, 0);

  
  	if (mode_inject)

  		ret = inject_region(image, size, region_type, inject_fname);

  	if (mode_write) {

  		int offset_uboot_top = 0;

  		int offset_uboot_start = 0;

  		for (wr_idx = 0; wr_idx < wr_num; wr_idx++) {

  			ifile = &input_file[wr_idx];

  			ret = write_data(image, size, ifile->addr,
  					 ifile->fname, offset_uboot_top,
  					 offset_uboot_start);

  			if (ret < 0)

  				break;
  		}
  	}

  
  	if (mode_spifreq)
  		set_spi_frequency(image, size, spifreq);
  
  	if (mode_em100)
  		set_em100_mode(image, size);
  
  	if (mode_locked)
  		lock_descriptor(image, size);
  
  	if (mode_unlocked)
  		unlock_descriptor(image, size);
  
  	if (write_it) {
  		if (outfile) {
  			ret = write_image(outfile, image, size);
  		} else {
  			if (lseek(bios_fd, 0, SEEK_SET)) {
  				perror("Error while seeking");
  				ret = -1;
  			}
  			if (write(bios_fd, image, size) != size) {
  				perror("Error while writing");
  				ret = -1;
  			}
  		}
  	}
  
  	free(image);
  	close(bios_fd);

  	return ret < 0 ? 1 : 0;

  }