text: /*
   * (C) Copyright 2002
   * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
   *
   * See file CREDITS for list of people who contributed to this
   * project.
   *
   * 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; either version 2 of
   * the License, or (at your option) any later version.
   *
   * 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., 59 Temple Place, Suite 330, Boston,
   * MA 02111-1307 USA
   */
  
  /*
   * Linux x86 zImage and bzImage loading
   *
   * based on the procdure described in
   * linux/Documentation/i386/boot.txt
   */
  
  #include <common.h>
  #include <asm/io.h>
  #include <asm/ptrace.h>
  #include <asm/zimage.h>
  #include <asm/realmode.h>
  #include <asm/byteorder.h>
  #include <asm/bootparam.h>
  #include <asm/ic/sc520.h>
  
  /*
   * Memory lay-out:
   *
   * relative to setup_base (which is 0x90000 currently)
   *
   *	0x0000-0x7FFF	Real mode kernel
   *	0x8000-0x8FFF	Stack and heap
   *	0x9000-0x90FF	Kernel command line
   */
  #define DEFAULT_SETUP_BASE  0x90000
  #define COMMAND_LINE_OFFSET 0x9000
  #define HEAP_END_OFFSET     0x8e00
  
  #define COMMAND_LINE_SIZE   2048
  
  static void build_command_line(char *command_line, int auto_boot)
  {
  	char *env_command_line;
  
  	command_line[0] = '\0';
  
  	env_command_line =  getenv("bootargs");
  
  	/* set console= argument if we use a serial console */
  	if (NULL == strstr(env_command_line, "console=")) {
  		if (0==strcmp(getenv("stdout"), "serial")) {
  
  			/* We seem to use serial console */
  			sprintf(command_line, "console=ttyS0,%s ",
  				 getenv("baudrate"));
  		}
  	}
  
  	if (auto_boot) {
  		strcat(command_line, "auto ");
  	}
  
  	if (NULL != env_command_line) {
  		strcat(command_line, env_command_line);
  	}
  
  
  	printf("Kernel command line: \"%s\"\n", command_line);
  }
  
  void *load_zimage(char *image, unsigned long kernel_size,
  		  unsigned long initrd_addr, unsigned long initrd_size,
  		  int auto_boot)
  {
  	void *setup_base;
  	int setup_size;
  	int bootproto;
  	int big_image;
  	void *load_address;
  
  	struct setup_header *hdr = (struct setup_header *)(image + SETUP_SECTS_OFF);
  
  	setup_base = (void*)DEFAULT_SETUP_BASE;	/* base address for real-mode segment */
  
  	if (KERNEL_MAGIC != hdr->boot_flag) {
  		printf("Error: Invalid Boot Flag (found 0x%04x, expected 0x%04x)\n",
  				hdr->boot_flag, KERNEL_MAGIC);
  		return 0;
  	} else {
  		printf("Valid Boot Flag\n");
  	}
  
  	/* determine boot protocol version */
  	if (KERNEL_V2_MAGIC == hdr->header) {
  		printf("Magic signature found\n");
  
  		bootproto = hdr->version;
  	} else {
  		/* Very old kernel */
  		printf("Magic signature not found\n");
  		bootproto = 0x0100;
  	}
  
  	/* determine size of setup */
  	if (0 == hdr->setup_sects) {
  		printf("Setup Sectors = 0 (defaulting to 4)\n");
  		setup_size = 5 * 512;
  	} else {
  		setup_size = (hdr->setup_sects + 1) * 512;
  	}
  
  	printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
  
  	if (setup_size > SETUP_MAX_SIZE) {
  		printf("Error: Setup is too large (%d bytes)\n", setup_size);
  	}
  
  	/* Determine image type */
  	big_image = (bootproto >= 0x0200) && (hdr->loadflags & BIG_KERNEL_FLAG);
  
  	/* Determine load address */
  	load_address = (void*)(big_image ? BZIMAGE_LOAD_ADDR : ZIMAGE_LOAD_ADDR);
  
  	/* load setup */
  	printf("Moving Real-Mode Code to 0x%8.8lx (%d bytes)\n", (ulong)setup_base, setup_size);
  	memmove(setup_base, image, setup_size);
  
  	printf("Using boot protocol version %x.%02x\n",
  	       (bootproto & 0xff00) >> 8, bootproto & 0xff);
  
  	if (bootproto == 0x0100) {
  
  		*(u16*)(setup_base + CMD_LINE_MAGIC_OFF) = COMMAND_LINE_MAGIC;
  		*(u16*)(setup_base + CMD_LINE_OFFSET_OFF) = COMMAND_LINE_OFFSET;
  
  		/* A very old kernel MUST have its real-mode code
  		 * loaded at 0x90000 */
  
  		if ((u32)setup_base != 0x90000) {
  			/* Copy the real-mode kernel */
  			memmove((void*)0x90000, setup_base, setup_size);
  			/* Copy the command line */
  			memmove((void*)0x99000, setup_base+COMMAND_LINE_OFFSET,
  			       COMMAND_LINE_SIZE);
  
  			setup_base = (void*)0x90000;		 /* Relocated */
  		}
  
  		/* It is recommended to clear memory up to the 32K mark */
  		memset((void*)0x90000 + setup_size, 0, SETUP_MAX_SIZE-setup_size);
  	}
  
  	/* We are now setting up the real-mode version of the header */
  	hdr = (struct setup_header *)(setup_base + SETUP_SECTS_OFF);
  
  	if (bootproto >= 0x0200) {
  		hdr->type_of_loader = 8;
  
  		if (hdr->setup_sects >= 15)
  			printf("Linux kernel version %s\n", (char *)
  					(setup_base + (hdr->kernel_version + 0x200)));
  		else
  			printf("Setup Sectors < 15 - Cannot print kernel version.\n");
  
  		if (initrd_addr) {
  			printf("Initial RAM disk at linear address 0x%08lx, size %ld bytes\n",
  			       initrd_addr, initrd_size);
  
  			hdr->ramdisk_image = initrd_addr;
  			hdr->ramdisk_size = initrd_size;
  		}
  	}
  
  	if (bootproto >= 0x0201) {
  		hdr->heap_end_ptr = HEAP_END_OFFSET;
  		hdr->loadflags |= HEAP_FLAG;
  	}
  
  	if (bootproto >= 0x0202) {
  		hdr->cmd_line_ptr = (u32)setup_base + COMMAND_LINE_OFFSET;
  	} else if (bootproto >= 0x0200) {
  
  		*(u16*)(setup_base + CMD_LINE_MAGIC_OFF) = COMMAND_LINE_MAGIC;
  		*(u16*)(setup_base + CMD_LINE_OFFSET_OFF) = COMMAND_LINE_OFFSET;
  
  		hdr->setup_move_size = 0x9100;
  	}
  
  	if (bootproto >= 0x0204)
  		kernel_size = hdr->syssize * 16;
  	else
  		kernel_size -= setup_size;
  
  
  	if (big_image) {
  		if ((kernel_size) > BZIMAGE_MAX_SIZE) {
  			printf("Error: bzImage kernel too big! (size: %ld, max: %d)\n",
  			       kernel_size, BZIMAGE_MAX_SIZE);
  			return 0;
  		}
  
  	} else if ((kernel_size) > ZIMAGE_MAX_SIZE) {
  		printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
  		       kernel_size, ZIMAGE_MAX_SIZE);
  		return 0;
  	}
  
  	/* build command line at COMMAND_LINE_OFFSET */
  	build_command_line(setup_base + COMMAND_LINE_OFFSET, auto_boot);
  
  	printf("Loading %czImage at address 0x%08x (%ld bytes)\n", big_image ? 'b' : ' ',
  	       (u32)load_address, kernel_size);
  
  
  	memmove(load_address, image + setup_size, kernel_size);
  
  	/* ready for booting */
  	return setup_base;
  }
  
  void boot_zimage(void *setup_base)
  {
  	struct pt_regs regs;
  
  	memset(&regs, 0, sizeof(struct pt_regs));
  	regs.xds = (u32)setup_base >> 4;
  	regs.xes = regs.xds;
  	regs.xss = regs.xds;
  	regs.esp = 0x9000;
  	regs.eflags = 0;
  	enter_realmode(((u32)setup_base+SETUP_START_OFFSET)>>4, 0, &regs, &regs);
  }
  
  int do_zboot (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
  {
  	void *base_ptr;
  	void *bzImage_addr = NULL;
  	char *s;
  	ulong bzImage_size = 0;
  
  	disable_interrupts();
  
  	/* Setup board for maximum PC/AT Compatibility */
  	setup_pcat_compatibility();
  
  	if (argc >= 2)
  		/* argv[1] holds the address of the bzImage */
  		s = argv[1];
  	else
  		s = getenv("fileaddr");
  
  	if (s)
  		bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
  
  	if (argc >= 3)
  		/* argv[2] holds the size of the bzImage */
  		bzImage_size = simple_strtoul(argv[2], NULL, 16);
  
  	/* Lets look for*/
  	base_ptr = load_zimage (bzImage_addr, bzImage_size, 0, 0, 0);
  
  	if (NULL == base_ptr) {
  		printf ("## Kernel loading failed ...\n");
  	} else {
  		printf ("## Transferring control to Linux (at address %08x) ...\n",
  			(u32)base_ptr);
  
  		/* we assume that the kernel is in place */
  		printf("\nStarting kernel ...\n\n");
  
  		boot_zimage(base_ptr);
  		/* does not return */
  	}
  
  	return -1;
  }
  
  U_BOOT_CMD(
  	zboot, 2, 0,	do_zboot,
  	"Boot bzImage",
  	""
  );
  