/*
   * (C) Copyright 2007-2011
   * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
   * Tom Cubie <tangliang@allwinnertech.com>
   *
   * a simple tool to generate bootable image for sunxi platform.
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  #include <fcntl.h>
  #include <stdio.h>
  #include <unistd.h>
  #include <stdlib.h>
  #include <string.h>
  #include <errno.h>
  #include <sys/types.h>
  #include <sys/stat.h>

  #include "../arch/arm/include/asm/arch-sunxi/spl.h"

  #define STAMP_VALUE                     0x5F0A6C39
  
  /* check sum functon from sun4i boot code */
  int gen_check_sum(struct boot_file_head *head_p)
  {
  	uint32_t length;
  	uint32_t *buf;
  	uint32_t loop;
  	uint32_t i;
  	uint32_t sum;

  	length = le32_to_cpu(head_p->length);

  	if ((length & 0x3) != 0)	/* must 4-byte-aligned */
  		return -1;
  	buf = (uint32_t *)head_p;

  	head_p->check_sum = cpu_to_le32(STAMP_VALUE);	/* fill stamp */

  	loop = length >> 2;
  
  	/* calculate the sum */
  	for (i = 0, sum = 0; i < loop; i++)

  		sum += le32_to_cpu(buf[i]);

  
  	/* write back check sum */

  	head_p->check_sum = cpu_to_le32(sum);

  
  	return 0;
  }
  
  #define ALIGN(x, a) __ALIGN_MASK((x), (typeof(x))(a)-1)
  #define __ALIGN_MASK(x, mask) (((x)+(mask))&~(mask))

  #define SUNXI_SRAM_SIZE 0x8000	/* SoC with smaller size are limited before */
  #define SRAM_LOAD_MAX_SIZE (SUNXI_SRAM_SIZE - sizeof(struct boot_file_head))

  
  /*
   * BROM (at least on A10 and A20) requires NAND-images to be explicitly aligned
   * to a multiple of 8K, and rejects the image otherwise. MMC-images are fine
   * with 512B blocks. To cater for both, align to the largest of the two.
   */
  #define BLOCK_SIZE 0x2000

  
  struct boot_img {
  	struct boot_file_head header;
  	char code[SRAM_LOAD_MAX_SIZE];
  	char pad[BLOCK_SIZE];
  };
  
  int main(int argc, char *argv[])
  {
  	int fd_in, fd_out;
  	struct boot_img img;

  	unsigned file_size;

  	int count;

  	char *tool_name = argv[0];
  	char *default_dt = NULL;

  	/* a sanity check */
  	if ((sizeof(img.header) % 32) != 0) {
  		fprintf(stderr, "ERROR: the SPL header must be a multiple ");
  		fprintf(stderr, "of 32 bytes.
  ");
  		return EXIT_FAILURE;
  	}
  
  	/* process optional command line switches */
  	while (argc >= 2 && argv[1][0] == '-') {
  		if (strcmp(argv[1], "--default-dt") == 0) {
  			if (argc >= 3) {
  				default_dt = argv[2];
  				argv += 2;
  				argc -= 2;
  				continue;
  			}
  			fprintf(stderr, "ERROR: no --default-dt arg
  ");
  			return EXIT_FAILURE;
  		} else {
  			fprintf(stderr, "ERROR: bad option '%s'
  ", argv[1]);
  			return EXIT_FAILURE;
  		}
  	}
  
  	if (argc < 3) {
  		printf("This program converts an input binary file to a sunxi bootable image.
  ");
  		printf("
  Usage: %s [options] input_file output_file
  ",
  		       tool_name);
  		printf("Where [options] may be:
  ");
  		printf("  --default-dt arg         - 'arg' is the default device tree name
  ");
  		printf("                             (CONFIG_DEFAULT_DEVICE_TREE).
  ");

  		return EXIT_FAILURE;
  	}
  
  	fd_in = open(argv[1], O_RDONLY);
  	if (fd_in < 0) {
  		perror("Open input file");
  		return EXIT_FAILURE;
  	}

  	memset(&img, 0, sizeof(img));

  
  	/* get input file size */
  	file_size = lseek(fd_in, 0, SEEK_END);
  
  	if (file_size > SRAM_LOAD_MAX_SIZE) {
  		fprintf(stderr, "ERROR: File too large!
  ");
  		return EXIT_FAILURE;

  	}
  
  	fd_out = open(argv[2], O_WRONLY | O_CREAT, 0666);
  	if (fd_out < 0) {
  		perror("Open output file");
  		return EXIT_FAILURE;
  	}
  
  	/* read file to buffer to calculate checksum */
  	lseek(fd_in, 0, SEEK_SET);

  	count = read(fd_in, img.code, file_size);
  	if (count != file_size) {

  		perror("Reading input image");
  		return EXIT_FAILURE;
  	}
  
  	/* fill the header */
  	img.header.b_instruction =	/* b instruction */
  		0xEA000000 |	/* jump to the first instr after the header */
  		((sizeof(struct boot_file_head) / sizeof(int) - 2)
  		 & 0x00FFFFFF);
  	memcpy(img.header.magic, BOOT0_MAGIC, 8);	/* no '0' termination */
  	img.header.length =

  		ALIGN(file_size + sizeof(struct boot_file_head), BLOCK_SIZE);

  	img.header.b_instruction = cpu_to_le32(img.header.b_instruction);
  	img.header.length = cpu_to_le32(img.header.length);

  
  	memcpy(img.header.spl_signature, SPL_SIGNATURE, 3); /* "sunxi" marker */
  	img.header.spl_signature[3] = SPL_HEADER_VERSION;

  	if (default_dt) {
  		if (strlen(default_dt) + 1 <= sizeof(img.header.string_pool)) {
  			strcpy((char *)img.header.string_pool, default_dt);
  			img.header.dt_name_offset =
  				cpu_to_le32(offsetof(struct boot_file_head,
  						     string_pool));
  		} else {
  			printf("WARNING: The SPL header is too small
  ");
  			printf("         and has no space to store the dt name.
  ");
  		}
  	}

  	gen_check_sum(&img.header);

  	count = write(fd_out, &img, le32_to_cpu(img.header.length));
  	if (count != le32_to_cpu(img.header.length)) {

  		perror("Writing output");
  		return EXIT_FAILURE;
  	}
  
  	close(fd_in);
  	close(fd_out);
  
  	return EXIT_SUCCESS;
  }