/*
   * (C) Copyright 2001
   * Hans-Joerg Frieden, Hyperion Entertainment
   * Hans-JoergF@hyperion-entertainment.com
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  #include <common.h>
  #include <command.h>
  #include <ide.h>
  #include "part_amiga.h"
  
  #ifdef HAVE_BLOCK_DEVICE
  
  #undef AMIGA_DEBUG
  
  #ifdef AMIGA_DEBUG
  #define PRINTF(fmt, args...) printf(fmt ,##args)
  #else
  #define PRINTF(fmt, args...)
  #endif
  
  struct block_header
  {
      u32 id;
      u32 summed_longs;
      s32 chk_sum;
  };
  
  static unsigned char block_buffer[DEFAULT_SECTOR_SIZE];
  static struct rigid_disk_block rdb = {0};
  static struct bootcode_block bootcode = {0};
  
  /*
   * Copy a bcpl to a c string
   */
  static void bcpl_strcpy(char *to, char *from)
  {
      int len = *from++;
  
      while (len)
      {
  	*to++ = *from++;
  	len--;
      }
      *to = 0;
  }
  
  /*
   * Print a BCPL String. BCPL strings start with a byte with the length
   * of the string, and don't contain a terminating nul character
   */
  static void bstr_print(char *string)
  {
      int len = *string++;
      char buffer[256];
      int i;
  
      i = 0;
      while (len)
      {
  	buffer[i++] = *string++;
  	len--;
      }
  
      buffer[i] = 0;
      printf("%-10s", buffer);
  }
  
  /*
   * Sum a block. The checksum of a block must end up at zero
   * to be valid. The chk_sum field is selected so that adding
   * it yields zero.
   */
  int sum_block(struct block_header *header)
  {
      s32 *block = (s32 *)header;
      u32 i;
      s32 sum = 0;
  
      for (i = 0; i < header->summed_longs; i++)
  	sum += *block++;
  
      return (sum != 0);
  }
  
  /*
   * Print an AmigaOS disk type. Disk types are a four-byte identifier
   * describing the file system. They are usually written as a three-letter
   * word followed by a backslash and a version number. For example,
   * DOS\0 would be the original file system. SFS\0 would be SmartFileSystem.
   * DOS\1 is FFS.
   */
  static void print_disk_type(u32 disk_type)
  {
      char buffer[6];
      buffer[0] = (disk_type & 0xFF000000)>>24;
      buffer[1] = (disk_type & 0x00FF0000)>>16;
      buffer[2] = (disk_type & 0x0000FF00)>>8;
      buffer[3] = '\\';
      buffer[4] = (disk_type & 0x000000FF) + '0';
      buffer[5] = 0;
      printf("%s", buffer);
  }
  
  /*
   * Print the info contained within the given partition block
   */
  static void print_part_info(struct partition_block *p)
  {
      struct amiga_part_geometry *g;
  
      g = (struct amiga_part_geometry *)&(p->environment);
  
      bstr_print(p->drive_name);
      printf("%6d\t%6d\t",
  	   g->low_cyl * g->block_per_track * g->surfaces ,
  	   (g->high_cyl - g->low_cyl + 1) * g->block_per_track * g->surfaces - 1);
      print_disk_type(g->dos_type);
      printf("\t%5d
  ", g->boot_priority);
  }
  
  /*
   * Search for the Rigid Disk Block. The rigid disk block is required
   * to be within the first 16 blocks of a drive, needs to have
   * the ID AMIGA_ID_RDISK ('RDSK') and needs to have a valid
   * sum-to-zero checksum
   */
  struct rigid_disk_block *get_rdisk(block_dev_desc_t *dev_desc)
  {
      int i;
      int limit;
      char *s;
  
      s = getenv("amiga_scanlimit");
      if (s)
  	limit = simple_strtoul(s, NULL, 10);
      else
  	limit = AMIGA_BLOCK_LIMIT;
  
      for (i=0; i<limit; i++)
      {
  	ulong res = dev_desc->block_read(dev_desc->dev, i, 1,
  					 (ulong *)block_buffer);
  	if (res == 1)
  	{
  	    struct rigid_disk_block *trdb = (struct rigid_disk_block *)block_buffer;
  	    if (trdb->id == AMIGA_ID_RDISK)
  	    {
  		PRINTF("Rigid disk block suspect at %d, checking checksum
  ",i);
  		if (sum_block((struct block_header *)block_buffer) == 0)
  		{
  		    PRINTF("FOUND
  ");
  		    memcpy(&rdb, trdb, sizeof(struct rigid_disk_block));
  		    return (struct rigid_disk_block *)&rdb;
  		}
  	    }
  	}
      }
      PRINTF("Done scanning, no RDB found
  ");
      return NULL;
  }
  
  /*
   * Search for boot code
   * Again, the first boot block must be located somewhere in the first 16 blocks, or rooted in the
   * Ridgid disk block
   */
  
  struct bootcode_block *get_bootcode(block_dev_desc_t *dev_desc)
  {
      int i;
      int limit;
      char *s;
  
      s = getenv("amiga_scanlimit");
      if (s)
  	limit = simple_strtoul(s, NULL, 10);
      else
  	limit = AMIGA_BLOCK_LIMIT;
  
      PRINTF("Scanning for BOOT from 0 to %d
  ", limit);
  
      for (i = 0; i < limit; i++)
      {
  	ulong res = dev_desc->block_read(dev_desc->dev, i, 1, (ulong *)block_buffer);
  	if (res == 1)
  	{
  	    struct bootcode_block *boot = (struct bootcode_block *)block_buffer;
  	    if (boot->id == AMIGA_ID_BOOT)
  	    {
  		PRINTF("BOOT block at %d, checking checksum
  ", i);
  		if (sum_block((struct block_header *)block_buffer) == 0)
  		{
  		    PRINTF("Found valid bootcode block
  ");
  		    memcpy(&bootcode, boot, sizeof(struct bootcode_block));
  		    return &bootcode;
  		}
  	    }
  	}
      }
  
      PRINTF("No boot code found on disk
  ");
      return 0;
  }
  
  /*
   * Test if the given partition has an Amiga partition table/Rigid
   * Disk block
   */
  int test_part_amiga(block_dev_desc_t *dev_desc)
  {
      struct rigid_disk_block *rdb;
      struct bootcode_block *bootcode;
  
      PRINTF("test_part_amiga: Testing for an Amiga RDB partition
  ");
  
      rdb = get_rdisk(dev_desc);
      if (rdb)
      {
  	bootcode = get_bootcode(dev_desc);
  	if (bootcode)
  	    PRINTF("test_part_amiga: bootable Amiga disk
  ");
  	else
  	    PRINTF("test_part_amiga: non-bootable Amiga disk
  ");
  
  	return 0;
      }
      else
      {
  	PRINTF("test_part_amiga: no RDB found
  ");
  	return -1;
      }
  
  }
  
  /*
   * Find partition number partnum on the given drive.
   */
  static struct partition_block *find_partition(block_dev_desc_t *dev_desc, int partnum)
  {
      struct rigid_disk_block *rdb;
      struct partition_block *p;
      u32 block;
  
      PRINTF("Trying to find partition block %d
  ", partnum);
      rdb = get_rdisk(dev_desc);
      if (!rdb)
      {
  	PRINTF("find_partition: no rdb found
  ");
  	return NULL;
      }
  
      PRINTF("find_partition: Scanning partition list
  ");
  
      block = rdb->partition_list;
      PRINTF("find_partition: partition list at 0x%x
  ", block);
  
      while (block != 0xFFFFFFFF)
      {
  	ulong res = dev_desc->block_read(dev_desc->dev, block, 1,
  					 (ulong *)block_buffer);
  	if (res == 1)
  	{
  	    p = (struct partition_block *)block_buffer;
  	    if (p->id == AMIGA_ID_PART)
  	    {
  		PRINTF("PART block suspect at 0x%x, checking checksum
  ",block);
  		if (sum_block((struct block_header *)p) == 0)
  		{
  		    if (partnum == 0) break;
  		    else
  		    {
  			partnum--;
  			block = p->next;
  		    }
  		}
  	    } else block = 0xFFFFFFFF;
  	} else block = 0xFFFFFFFF;
      }
  
      if (block == 0xFFFFFFFF)
      {
  	PRINTF("PART block not found
  ");
  	return NULL;
      }
  
      return (struct partition_block *)block_buffer;
  }
  
  /*
   * Get info about a partition
   */
  int get_partition_info_amiga (block_dev_desc_t *dev_desc, int part, disk_partition_t *info)
  {
      struct partition_block *p = find_partition(dev_desc, part-1);
      struct amiga_part_geometry *g;
      u32 disk_type;
  
      if (!p) return -1;
  
      g = (struct amiga_part_geometry *)&(p->environment);
      info->start = g->low_cyl  * g->block_per_track * g->surfaces;
      info->size  = (g->high_cyl - g->low_cyl + 1) * g->block_per_track * g->surfaces - 1;
      info->blksz = rdb.block_bytes;
      bcpl_strcpy(info->name, p->drive_name);
  
  
      disk_type = g->dos_type;
  
      info->type[0] = (disk_type & 0xFF000000)>>24;
      info->type[1] = (disk_type & 0x00FF0000)>>16;
      info->type[2] = (disk_type & 0x0000FF00)>>8;
      info->type[3] = '\\';
      info->type[4] = (disk_type & 0x000000FF) + '0';
      info->type[5] = 0;
  
      return 0;
  }
  
  void print_part_amiga (block_dev_desc_t *dev_desc)
  {
      struct rigid_disk_block *rdb;
      struct bootcode_block *boot;
      struct partition_block *p;
      u32 block;
      int i = 1;
  
      rdb = get_rdisk(dev_desc);
      if (!rdb)
      {
  	PRINTF("print_part_amiga: no rdb found
  ");
  	return;
      }
  
      PRINTF("print_part_amiga: Scanning partition list
  ");
  
      block = rdb->partition_list;
      PRINTF("print_part_amiga: partition list at 0x%x
  ", block);
  
      printf("Summary:  DiskBlockSize: %d
  "
  	   "          Cylinders    : %d
  "
  	   "          Sectors/Track: %d
  "
  	   "          Heads        : %d
  
  ",
  	   rdb->block_bytes, rdb->cylinders, rdb->sectors,
  	   rdb->heads);
  
      printf("                 First   Num. 
  "
  	   "Nr.  Part. Name  Block   Block  Type        Boot Priority
  ");
  
      while (block != 0xFFFFFFFF)
      {
  	ulong res;
  
  	PRINTF("Trying to load block #0x%X
  ", block);
  
  	res = dev_desc->block_read(dev_desc->dev, block, 1,
  				   (ulong *)block_buffer);
  	if (res == 1)
  	{
  	    p = (struct partition_block *)block_buffer;
  	    if (p->id == AMIGA_ID_PART)
  	    {
  		PRINTF("PART block suspect at 0x%x, checking checksum
  ",block);
  		if (sum_block((struct block_header *)p) == 0)
  		{
  		    printf("%-4d ", i); i++;
  		    print_part_info(p);
  		    block = p->next;
  		}
  	    } else block = 0xFFFFFFFF;
  	} else block = 0xFFFFFFFF;
      }
  
      boot = get_bootcode(dev_desc);
      if (boot)
      {
  	printf("Disk is bootable
  ");
      }
  }
  
  #endif