common/cmd_bootm.c

/*
 * (C) Copyright 2000-2002
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * 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
 */

/*
 * Boot support
 */
#include <common.h>
#include <watchdog.h>
#include <command.h>
#include <cmd_boot.h>
#include <image.h>
#include <malloc.h>
#include <zlib.h>
#include <asm/byteorder.h>
#if (CONFIG_COMMANDS & CFG_CMD_DATE) || defined(CONFIG_TIMESTAMP)
#include <rtc.h>
#endif

#ifdef CFG_HUSH_PARSER
#include <hush.h>
#endif

#ifdef CONFIG_SHOW_BOOT_PROGRESS
# include <status_led.h>
# define SHOW_BOOT_PROGRESS(arg)	show_boot_progress(arg)
#else
# define SHOW_BOOT_PROGRESS(arg)
#endif

#ifdef CFG_INIT_RAM_LOCK
#include <asm/cache.h>
#endif

#ifdef CONFIG_LOGBUFFER
#include <logbuff.h>
#endif

/*
 * Some systems (for example LWMON) have very short watchdog periods;
 * we must make sure to split long operations like memmove() or
 * crc32() into reasonable chunks.
 */
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
# define CHUNKSZ (64 * 1024)
#endif

int  gunzip (void *, int, unsigned char *, int *);

static void *zalloc(void *, unsigned, unsigned);
static void zfree(void *, void *, unsigned);

#if (CONFIG_COMMANDS & CFG_CMD_IMI)
static int image_info (unsigned long addr);
#endif
static void print_type (image_header_t *hdr);

#ifdef __I386__
image_header_t *fake_header(image_header_t *hdr, void *ptr, int size);
#endif

/*
 *  Continue booting an OS image; caller already has:
 *  - copied image header to global variable `header'
 *  - checked header magic number, checksums (both header & image),
 *  - verified image architecture (PPC) and type (KERNEL or MULTI),
 *  - loaded (first part of) image to header load address,
 *  - disabled interrupts.
 */
typedef void boot_os_Fcn (cmd_tbl_t *cmdtp, int flag,
			  int	argc, char *argv[],
			  ulong	addr,		/* of image to boot */
			  ulong	*len_ptr,	/* multi-file image length table */
			  int	verify);	/* getenv("verify")[0] != 'n' */

#ifdef CONFIG_PPC
static boot_os_Fcn do_bootm_linux;
#else
extern boot_os_Fcn do_bootm_linux;
#endif
static boot_os_Fcn do_bootm_netbsd;
static boot_os_Fcn do_bootm_rtems;
#if (CONFIG_COMMANDS & CFG_CMD_ELF)
static boot_os_Fcn do_bootm_vxworks;
static boot_os_Fcn do_bootm_qnxelf;
int do_bootvx ( cmd_tbl_t *cmdtp, int flag, int argc, char *argv[] );
int do_bootelf (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[] );
#endif /* CFG_CMD_ELF */

image_header_t header;

ulong load_addr = CFG_LOAD_ADDR;		/* Default Load Address */

int do_bootm (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
	ulong	iflag;
	ulong	addr;
	ulong	data, len, checksum;
	ulong  *len_ptr;
	int	i, verify;
	char	*name, *s;
	int	(*appl)(cmd_tbl_t *, int, int, char *[]);
	image_header_t *hdr = &header;

	s = getenv ("verify");
	verify = (s && (*s == 'n')) ? 0 : 1;

	if (argc < 2) {
		addr = load_addr;
	} else {
		addr = simple_strtoul(argv[1], NULL, 16);
	}

	SHOW_BOOT_PROGRESS (1);
	printf ("## Booting image at %08lx ...\n", addr);

	/* Copy header so we can blank CRC field for re-calculation */
	memmove (&header, (char *)addr, sizeof(image_header_t));

	if (ntohl(hdr->ih_magic) != IH_MAGIC) {
#ifdef __I386__	/* correct image format not implemented yet - fake it */
		if (fake_header(hdr, (void*)addr, -1) != NULL) {
			/* to compensate for the addition below */
			addr -= sizeof(image_header_t);
			/* turnof verify,
			 * fake_header() does not fake the data crc
			 */
			verify = 0;
		} else
#endif	/* __I386__ */
	    {
		printf ("Bad Magic Number\n");
		SHOW_BOOT_PROGRESS (-1);
		return 1;
	    }
	}
	SHOW_BOOT_PROGRESS (2);

	data = (ulong)&header;
	len  = sizeof(image_header_t);

	checksum = ntohl(hdr->ih_hcrc);
	hdr->ih_hcrc = 0;

	if (crc32 (0, (char *)data, len) != checksum) {
		printf ("Bad Header Checksum\n");
		SHOW_BOOT_PROGRESS (-2);
		return 1;
	}
	SHOW_BOOT_PROGRESS (3);

	/* for multi-file images we need the data part, too */
	print_image_hdr (hdr);

	data = addr + sizeof(image_header_t);
	len  = ntohl(hdr->ih_size);

	if (verify) {
		printf ("   Verifying Checksum ... ");
		if (crc32 (0, (char *)data, len) != ntohl(hdr->ih_dcrc)) {
			printf ("Bad Data CRC\n");
			SHOW_BOOT_PROGRESS (-3);
			return 1;
		}
		printf ("OK\n");
	}
	SHOW_BOOT_PROGRESS (4);

	len_ptr = (ulong *)data;

#if defined(__PPC__)
	if (hdr->ih_arch != IH_CPU_PPC)
#elif defined(__ARM__)
	if (hdr->ih_arch != IH_CPU_ARM)
#elif defined(__I386__)
	if (hdr->ih_arch != IH_CPU_I386)
#elif defined(__mips__)
	if (hdr->ih_arch != IH_CPU_MIPS)	
#else
# error Unknown CPU type
#endif
	{
		printf ("Unsupported Architecture 0x%x\n", hdr->ih_arch);
		SHOW_BOOT_PROGRESS (-4);
		return 1;
	}
	SHOW_BOOT_PROGRESS (5);

	switch (hdr->ih_type) {
	case IH_TYPE_STANDALONE:	name = "Standalone Application";
					break;
	case IH_TYPE_KERNEL:		name = "Kernel Image";
					break;
	case IH_TYPE_MULTI:		name = "Multi-File Image";
					len  = ntohl(len_ptr[0]);
					/* OS kernel is always the first image */
					data += 8; /* kernel_len + terminator */
					for (i=1; len_ptr[i]; ++i)
						data += 4;
					break;
	default: printf ("Wrong Image Type for %s command\n", cmdtp->name);
		SHOW_BOOT_PROGRESS (-5);
		return 1;
	}
	SHOW_BOOT_PROGRESS (6);

	/*
	 * We have reached the point of no return: we are going to
	 * overwrite all exception vector code, so we cannot easily
	 * recover from any failures any more...
	 */

	iflag = disable_interrupts();

#ifdef CONFIG_AMIGAONEG3SE
	/*
	 * We've possible left the caches enabled during 
	 * bios emulation, so turn them off again
	 */
	icache_disable();
	invalidate_l1_instruction_cache();
	flush_data_cache();
	dcache_disable();
#endif

	switch (hdr->ih_comp) {
	case IH_COMP_NONE:
		if(ntohl(hdr->ih_load) == addr) {
			printf ("   XIP %s ... ", name);
		} else {
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
			size_t l = len;
			void *to = (void *)ntohl(hdr->ih_load);
			void *from = (void *)data;

			printf ("   Loading %s ... ", name);

			while (l > 0) {
				size_t tail = (l > CHUNKSZ) ? CHUNKSZ : l;
				WATCHDOG_RESET();
				memmove (to, from, tail);
				to += tail;
				from += tail;
				l -= tail;
			}
#else	/* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
			memmove ((void *) ntohl(hdr->ih_load), (uchar *)data, len);
#endif	/* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
		}
		break;
	case IH_COMP_GZIP:
		printf ("   Uncompressing %s ... ", name);
		if (gunzip ((void *)ntohl(hdr->ih_load), 0x400000,
			    (uchar *)data, (int *)&len) != 0) {
			printf ("GUNZIP ERROR - must RESET board to recover\n");
			SHOW_BOOT_PROGRESS (-6);
			do_reset (cmdtp, flag, argc, argv);
		}
		break;
	default:
		if (iflag)
			enable_interrupts();
		printf ("Unimplemented compression type %d\n", hdr->ih_comp);
		SHOW_BOOT_PROGRESS (-7);
		return 1;
	}
	printf ("OK\n");
	SHOW_BOOT_PROGRESS (7);

	switch (hdr->ih_type) {
	case IH_TYPE_STANDALONE:
		if (iflag)
			enable_interrupts();

		/* load (and uncompress), but don't start if "autostart"
		 * is set to "no"
		 */
		if (((s = getenv("autostart")) != NULL) && (strcmp(s,"no") == 0))
			return 0;
		appl = (int (*)(cmd_tbl_t *, int, int, char *[]))ntohl(hdr->ih_ep);
		(*appl)(cmdtp, flag, argc-1, &argv[1]);
		return 0;
	case IH_TYPE_KERNEL:
	case IH_TYPE_MULTI:
		/* handled below */
		break;
	default:
		if (iflag)
			enable_interrupts();
		printf ("Can't boot image type %d\n", hdr->ih_type);
		SHOW_BOOT_PROGRESS (-8);
		return 1;
	}
	SHOW_BOOT_PROGRESS (8);

	switch (hdr->ih_os) {
	default:			/* handled by (original) Linux case */
	case IH_OS_LINUX:
	    do_bootm_linux  (cmdtp, flag, argc, argv,
			     addr, len_ptr, verify);
	    break;
	case IH_OS_NETBSD:
	    do_bootm_netbsd (cmdtp, flag, argc, argv,
			     addr, len_ptr, verify);
	    break;
	    
	case IH_OS_RTEMS:
	    do_bootm_rtems (cmdtp, flag, argc, argv,
			     addr, len_ptr, verify);
	    break;
	     
#if (CONFIG_COMMANDS & CFG_CMD_ELF)
	case IH_OS_VXWORKS:
	    do_bootm_vxworks (cmdtp, flag, argc, argv,
			      addr, len_ptr, verify);
	    break;
	case IH_OS_QNX:
	    do_bootm_qnxelf (cmdtp, flag, argc, argv,
			      addr, len_ptr, verify);
	    break;
#endif /* CFG_CMD_ELF */
	}

	SHOW_BOOT_PROGRESS (-9);
#ifdef DEBUG
	printf ("\n## Control returned to monitor - resetting...\n");
	do_reset (cmdtp, flag, argc, argv);
#endif
	return 1;
}

#ifdef CONFIG_PPC
static void
do_bootm_linux (cmd_tbl_t *cmdtp, int flag,
		int	argc, char *argv[],
		ulong	addr,
		ulong	*len_ptr,
		int	verify)
{
	DECLARE_GLOBAL_DATA_PTR;

	ulong	sp;
	ulong	len, checksum;
	ulong	initrd_start, initrd_end;
	ulong	cmd_start, cmd_end;
	ulong	initrd_high;
	ulong	data;
	char    *cmdline;
	char	*s;
	bd_t	*kbd;
	void	(*kernel)(bd_t *, ulong, ulong, ulong, ulong);
	image_header_t *hdr = &header;

	if ((s = getenv ("initrd_high")) != NULL) {
		/* a value of "no" or a similar string will act like 0,
		 * turning the "load high" feature off. This is intentional.
		 */
		initrd_high = simple_strtoul(s, NULL, 16);
	} else {	/* not set, no restrictions to load high */
		initrd_high = ~0;
	}

#ifdef CONFIG_LOGBUFFER
	kbd=gd->bd;
	/* Prevent initrd from overwriting logbuffer */
	if (initrd_high < (kbd->bi_memsize-LOGBUFF_LEN-LOGBUFF_OVERHEAD))
		initrd_high = kbd->bi_memsize-LOGBUFF_LEN-LOGBUFF_OVERHEAD;
	debug ("## Logbuffer at 0x%08lX ", kbd->bi_memsize-LOGBUFF_LEN);
#endif

	/*
	 * Booting a (Linux) kernel image
	 *
	 * Allocate space for command line and board info - the
	 * address should be as high as possible within the reach of
	 * the kernel (see CFG_BOOTMAPSZ settings), but in unused
	 * memory, which means far enough below the current stack
	 * pointer.
	 */

	asm( "mr %0,1": "=r"(sp) : );

	debug ("## Current stack ends at 0x%08lX ", sp);

	sp -= 2048;		/* just to be sure */
	if (sp > CFG_BOOTMAPSZ)
		sp = CFG_BOOTMAPSZ;
	sp &= ~0xF;

	debug ("=> set upper limit to 0x%08lX\n", sp);

	cmdline = (char *)((sp - CFG_BARGSIZE) & ~0xF);
	kbd = (bd_t *)(((ulong)cmdline - sizeof(bd_t)) & ~0xF);

	if ((s = getenv("bootargs")) == NULL)
		s = "";

	strcpy (cmdline, s);

	cmd_start    = (ulong)&cmdline[0];
	cmd_end      = cmd_start + strlen(cmdline);

	*kbd = *(gd->bd);

#ifdef	DEBUG
	printf ("## cmdline at 0x%08lX ... 0x%08lX\n", cmd_start, cmd_end);

	do_bdinfo (NULL, 0, 0, NULL);
#endif

	if ((s = getenv ("clocks_in_mhz")) != NULL) {
		/* convert all clock information to MHz */
		kbd->bi_intfreq /= 1000000L;
		kbd->bi_busfreq /= 1000000L;
#if defined(CONFIG_8260)
		kbd->bi_cpmfreq /= 1000000L;
		kbd->bi_brgfreq /= 1000000L;
		kbd->bi_sccfreq /= 1000000L;
		kbd->bi_vco     /= 1000000L;
#endif /* CONFIG_8260 */
	}

	kernel = (void (*)(bd_t *, ulong, ulong, ulong, ulong))hdr->ih_ep;

	/*
	 * Check if there is an initrd image
	 */
	if (argc >= 3) {
		SHOW_BOOT_PROGRESS (9);

		addr = simple_strtoul(argv[2], NULL, 16);

		printf ("## Loading RAMDisk Image at %08lx ...\n", addr);

		/* Copy header so we can blank CRC field for re-calculation */
		memmove (&header, (char *)addr, sizeof(image_header_t));

		if (hdr->ih_magic  != IH_MAGIC) {
			printf ("Bad Magic Number\n");
			SHOW_BOOT_PROGRESS (-10);
			do_reset (cmdtp, flag, argc, argv);
		}

		data = (ulong)&header;
		len  = sizeof(image_header_t);

		checksum = hdr->ih_hcrc;
		hdr->ih_hcrc = 0;

		if (crc32 (0, (char *)data, len) != checksum) {
			printf ("Bad Header Checksum\n");
			SHOW_BOOT_PROGRESS (-11);
			do_reset (cmdtp, flag, argc, argv);
		}

		SHOW_BOOT_PROGRESS (10);

		print_image_hdr (hdr);

		data = addr + sizeof(image_header_t);
		len  = hdr->ih_size;

		if (verify) {
			ulong csum = 0;
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
			ulong cdata = data, edata = cdata + len;
#endif	/* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */

			printf ("   Verifying Checksum ... ");

#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)

			while (cdata < edata) {
				ulong chunk = edata - cdata;

				if (chunk > CHUNKSZ)
					chunk = CHUNKSZ;
				csum = crc32 (csum, (char *)cdata, chunk);
				cdata += chunk;

				WATCHDOG_RESET();
			}
#else	/* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
			csum = crc32 (0, (char *)data, len);
#endif	/* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */

			if (csum != hdr->ih_dcrc) {
				printf ("Bad Data CRC\n");
				SHOW_BOOT_PROGRESS (-12);
				do_reset (cmdtp, flag, argc, argv);
			}
			printf ("OK\n");
		}

		SHOW_BOOT_PROGRESS (11);

		if ((hdr->ih_os   != IH_OS_LINUX)	||
		    (hdr->ih_arch != IH_CPU_PPC)	||
		    (hdr->ih_type != IH_TYPE_RAMDISK)	) {
			printf ("No Linux PPC Ramdisk Image\n");
			SHOW_BOOT_PROGRESS (-13);
			do_reset (cmdtp, flag, argc, argv);
		}

		/*
		 * Now check if we have a multifile image
		 */
	} else if ((hdr->ih_type==IH_TYPE_MULTI) && (len_ptr[1])) {
		u_long tail    = ntohl(len_ptr[0]) % 4;
		int i;

		SHOW_BOOT_PROGRESS (13);

		/* skip kernel length and terminator */
		data = (ulong)(&len_ptr[2]);
		/* skip any additional image length fields */
		for (i=1; len_ptr[i]; ++i)
			data += 4;
		/* add kernel length, and align */
		data += ntohl(len_ptr[0]);
		if (tail) {
			data += 4 - tail;
		}

		len   = ntohl(len_ptr[1]);

	} else {
		/*
		 * no initrd image
		 */
		SHOW_BOOT_PROGRESS (14);

		len = data = 0;
	}

	if (!data) {
		debug ("No initrd\n");
	}

	if (data) {
		initrd_start  = (ulong)kbd - len;
		initrd_start &= ~(4096 - 1);	/* align on page */

		if (initrd_high) {
			ulong nsp;

			/*
			 * the inital ramdisk does not need to be within
			 * CFG_BOOTMAPSZ as it is not accessed until after
			 * the mm system is initialised.
			 *
			 * do the stack bottom calculation again and see if
			 * the initrd will fit just below the monitor stack
			 * bottom without overwriting the area allocated
			 * above for command line args and board info.
			 */
			asm( "mr %0,1": "=r"(nsp) : );
			nsp -= 2048;		/* just to be sure */
			nsp &= ~0xF;
			if (nsp > initrd_high)	/* limit as specified */
				nsp = initrd_high;
			nsp -= len;
			nsp &= ~(4096 - 1);	/* align on page */
			if (nsp >= sp)
				initrd_start = nsp;
		}

		SHOW_BOOT_PROGRESS (12);

		debug ("## initrd at 0x%08lX ... 0x%08lX (len=%ld=0x%lX)\n",
			data, data + len - 1, len, len);

		initrd_end    = initrd_start + len;
		printf ("   Loading Ramdisk to %08lx, end %08lx ... ",
			initrd_start, initrd_end);
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
		{
			size_t l = len;
			void *to = (void *)initrd_start;
			void *from = (void *)data;

			while (l > 0) {
				size_t tail = (l > CHUNKSZ) ? CHUNKSZ : l;
				WATCHDOG_RESET();
				memmove (to, from, tail);
				to += tail;
				from += tail;
				l -= tail;
			}
		}
#else	/* !(CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG) */
		memmove ((void *)initrd_start, (void *)data, len);
#endif	/* CONFIG_HW_WATCHDOG || CONFIG_WATCHDOG */
		printf ("OK\n");
	} else {
		initrd_start = 0;
		initrd_end = 0;
	}


	debug ("## Transferring control to Linux (at address %08lx) ...\n",
		(ulong)kernel);

	SHOW_BOOT_PROGRESS (15);

#ifdef CFG_INIT_RAM_LOCK
	unlock_ram_in_cache();
#endif
	/*
	 * Linux Kernel Parameters:
	 *   r3: ptr to board info data
	 *   r4: initrd_start or 0 if no initrd
	 *   r5: initrd_end - unused if r4 is 0
	 *   r6: Start of command line string
	 *   r7: End   of command line string
	 */
	(*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end);
}
#endif /* CONFIG_PPC */

static void
do_bootm_netbsd (cmd_tbl_t *cmdtp, int flag,
		int	argc, char *argv[],
		ulong	addr,
		ulong	*len_ptr,
		int	verify)
{
	DECLARE_GLOBAL_DATA_PTR;

	image_header_t *hdr = &header;

	void	(*loader)(bd_t *, image_header_t *, char *, char *);
	image_header_t *img_addr;
	char     *consdev;
	char     *cmdline;


	/*
	 * Booting a (NetBSD) kernel image
	 *
	 * This process is pretty similar to a standalone application:
	 * The (first part of an multi-) image must be a stage-2 loader,
	 * which in turn is responsible for loading & invoking the actual
	 * kernel.  The only differences are the parameters being passed:
	 * besides the board info strucure, the loader expects a command
	 * line, the name of the console device, and (optionally) the
	 * address of the original image header.
	 */

	img_addr = 0;
	if ((hdr->ih_type==IH_TYPE_MULTI) && (len_ptr[1]))
		img_addr = (image_header_t *) addr;


	consdev = "";
#if   defined (CONFIG_8xx_CONS_SMC1)
	consdev = "smc1";
#elif defined (CONFIG_8xx_CONS_SMC2)
	consdev = "smc2";
#elif defined (CONFIG_8xx_CONS_SCC2)
	consdev = "scc2";
#elif defined (CONFIG_8xx_CONS_SCC3)
	consdev = "scc3";
#endif

	if (argc > 2) {
		ulong len;
		int   i;

		for (i=2, len=0 ; i<argc ; i+=1)
			len += strlen (argv[i]) + 1;
		cmdline = malloc (len);

		for (i=2, len=0 ; i<argc ; i+=1) {
			if (i > 2)
				cmdline[len++] = ' ';
			strcpy (&cmdline[len], argv[i]);
			len += strlen (argv[i]);
		}
	} else if ((cmdline = getenv("bootargs")) == NULL) {
		cmdline = "";
	}

	loader = (void (*)(bd_t *, image_header_t *, char *, char *)) hdr->ih_ep;

	printf ("## Transferring control to NetBSD stage-2 loader (at address %08lx) ...\n",
		(ulong)loader);

	SHOW_BOOT_PROGRESS (15);

	/*
	 * NetBSD Stage-2 Loader Parameters:
	 *   r3: ptr to board info data
	 *   r4: image address
	 *   r5: console device
	 *   r6: boot args string
	 */
	(*loader) (gd->bd, img_addr, consdev, cmdline);
}

#if (CONFIG_COMMANDS & CFG_CMD_BOOTD)
int do_bootd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
	int rcode = 0;
#ifndef CFG_HUSH_PARSER
	if (run_command (getenv ("bootcmd"), flag) < 0) rcode = 1;
#else
	if (parse_string_outer(getenv("bootcmd"),
		FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP) != 0 ) rcode = 1;
#endif
	return rcode;
}
#endif

#if (CONFIG_COMMANDS & CFG_CMD_IMI)
int do_iminfo ( cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
	int	arg;
	ulong	addr;
	int     rcode=0;

	if (argc < 2) {
		return image_info (load_addr);
	}

	for (arg=1; arg <argc; ++arg) {
		addr = simple_strtoul(argv[arg], NULL, 16);
		if (image_info (addr) != 0) rcode = 1;
	}
	return rcode;
}

static int image_info (ulong addr)
{
	ulong	data, len, checksum;
	image_header_t *hdr = &header;

	printf ("\n## Checking Image at %08lx ...\n", addr);

	/* Copy header so we can blank CRC field for re-calculation */
	memmove (&header, (char *)addr, sizeof(image_header_t));

	if (ntohl(hdr->ih_magic) != IH_MAGIC) {
		printf ("   Bad Magic Number\n");
		return 1;
	}

	data = (ulong)&header;
	len  = sizeof(image_header_t);

	checksum = ntohl(hdr->ih_hcrc);
	hdr->ih_hcrc = 0;

	if (crc32 (0, (char *)data, len) != checksum) {
		printf ("   Bad Header Checksum\n");
		return 1;
	}

	/* for multi-file images we need the data part, too */
	print_image_hdr ((image_header_t *)addr);

	data = addr + sizeof(image_header_t);
	len  = ntohl(hdr->ih_size);

	printf ("   Verifying Checksum ... ");
	if (crc32 (0, (char *)data, len) != ntohl(hdr->ih_dcrc)) {
		printf ("   Bad Data CRC\n");
		return 1;
	}
	printf ("OK\n");
	return 0;
}
#endif	/* CFG_CMD_IMI */

void
print_image_hdr (image_header_t *hdr)
{
#if (CONFIG_COMMANDS & CFG_CMD_DATE) || defined(CONFIG_TIMESTAMP)
	time_t timestamp = (time_t)ntohl(hdr->ih_time);
	struct rtc_time tm;
#endif

	printf ("   Image Name:   %.*s\n", IH_NMLEN, hdr->ih_name);
#if (CONFIG_COMMANDS & CFG_CMD_DATE) || defined(CONFIG_TIMESTAMP)
	to_tm (timestamp, &tm);
	printf ("   Created:      %4d-%02d-%02d  %2d:%02d:%02d UTC\n",
		tm.tm_year, tm.tm_mon, tm.tm_mday,
		tm.tm_hour, tm.tm_min, tm.tm_sec);
#endif	/* CFG_CMD_DATE, CONFIG_TIMESTAMP */
	printf ("   Image Type:   "); print_type(hdr); printf ("\n");
	printf ("   Data Size:    %d Bytes = ", ntohl(hdr->ih_size));
	print_size (ntohl(hdr->ih_size), "\n");
	printf ("   Load Address: %08x\n", ntohl(hdr->ih_load));
	printf ("   Entry Point:  %08x\n", ntohl(hdr->ih_ep));

	if (hdr->ih_type == IH_TYPE_MULTI) {
		int i;
		ulong len;
		ulong *len_ptr = (ulong *)((ulong)hdr + sizeof(image_header_t));

		printf ("   Contents:\n");
		for (i=0; (len = ntohl(*len_ptr)); ++i, ++len_ptr) {
			printf ("   Image %d: %8ld Bytes = ", i, len);
			print_size (len, "\n");
		}
	}
}


static void
print_type (image_header_t *hdr)
{
	char *os, *arch, *type, *comp;

	switch (hdr->ih_os) {
	case IH_OS_INVALID:	os = "Invalid OS";		break;
	case IH_OS_NETBSD:	os = "NetBSD";			break;
	case IH_OS_LINUX:	os = "Linux";			break;
	case IH_OS_VXWORKS:	os = "VxWorks";			break;
	case IH_OS_QNX:		os = "QNX";			break;
	case IH_OS_U_BOOT:	os = "U-Boot";			break;
	case IH_OS_RTEMS:	os = "RTEMS";			break;
	default:		os = "Unknown OS";		break;
	}

	switch (hdr->ih_arch) {
	case IH_CPU_INVALID:	arch = "Invalid CPU";		break;
	case IH_CPU_ALPHA:	arch = "Alpha";			break;
	case IH_CPU_ARM:	arch = "ARM";			break;
	case IH_CPU_I386:	arch = "Intel x86";		break;
	case IH_CPU_IA64:	arch = "IA64";			break;
	case IH_CPU_MIPS:	arch = "MIPS";			break;
	case IH_CPU_MIPS64:	arch = "MIPS 64 Bit";		break;
	case IH_CPU_PPC:	arch = "PowerPC";		break;
	case IH_CPU_S390:	arch = "IBM S390";		break;
	case IH_CPU_SH:		arch = "SuperH";		break;
	case IH_CPU_SPARC:	arch = "SPARC";			break;
	case IH_CPU_SPARC64:	arch = "SPARC 64 Bit";		break;
	default:		arch = "Unknown Architecture";	break;
	}

	switch (hdr->ih_type) {
	case IH_TYPE_INVALID:	type = "Invalid Image";		break;
	case IH_TYPE_STANDALONE:type = "Standalone Program";	break;
	case IH_TYPE_KERNEL:	type = "Kernel Image";		break;
	case IH_TYPE_RAMDISK:	type = "RAMDisk Image";		break;
	case IH_TYPE_MULTI:	type = "Multi-File Image";	break;
	case IH_TYPE_FIRMWARE:	type = "Firmware";		break;
	case IH_TYPE_SCRIPT:	type = "Script";		break;
	default:		type = "Unknown Image";		break;
	}

	switch (hdr->ih_comp) {
	case IH_COMP_NONE:	comp = "uncompressed";		break;
	case IH_COMP_GZIP:	comp = "gzip compressed";	break;
	case IH_COMP_BZIP2:	comp = "bzip2 compressed";	break;
	default:		comp = "unknown compression";	break;
	}

	printf ("%s %s %s (%s)", arch, os, type, comp);
}

#define	ZALLOC_ALIGNMENT	16

static void *zalloc(void *x, unsigned items, unsigned size)
{
	void *p;

	size *= items;
	size = (size + ZALLOC_ALIGNMENT - 1) & ~(ZALLOC_ALIGNMENT - 1);

	p = malloc (size);

	return (p);
}

static void zfree(void *x, void *addr, unsigned nb)
{
	free (addr);
}

#define HEAD_CRC	2
#define EXTRA_FIELD	4
#define ORIG_NAME	8
#define COMMENT		0x10
#define RESERVED	0xe0

#define DEFLATED	8

int gunzip(void *dst, int dstlen, unsigned char *src, int *lenp)
{
	z_stream s;
	int r, i, flags;

	/* skip header */
	i = 10;
	flags = src[3];
	if (src[2] != DEFLATED || (flags & RESERVED) != 0) {
		printf ("Error: Bad gzipped data\n");
		return (-1);
	}
	if ((flags & EXTRA_FIELD) != 0)
		i = 12 + src[10] + (src[11] << 8);
	if ((flags & ORIG_NAME) != 0)
		while (src[i++] != 0)
			;
	if ((flags & COMMENT) != 0)
		while (src[i++] != 0)
			;
	if ((flags & HEAD_CRC) != 0)
		i += 2;
	if (i >= *lenp) {
		printf ("Error: gunzip out of data in header\n");
		return (-1);
	}

	s.zalloc = zalloc;
	s.zfree = zfree;
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
	s.outcb = (cb_func)WATCHDOG_RESET;
#else
	s.outcb = Z_NULL;
#endif	/* CONFIG_HW_WATCHDOG */

	r = inflateInit2(&s, -MAX_WBITS);
	if (r != Z_OK) {
		printf ("Error: inflateInit2() returned %d\n", r);
		return (-1);
	}
	s.next_in = src + i;
	s.avail_in = *lenp - i;
	s.next_out = dst;
	s.avail_out = dstlen;
	r = inflate(&s, Z_FINISH);
	if (r != Z_OK && r != Z_STREAM_END) {
		printf ("Error: inflate() returned %d\n", r);
		return (-1);
	}
	*lenp = s.next_out - (unsigned char *) dst;
	inflateEnd(&s);

	return (0);
}

static void
do_bootm_rtems (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
		ulong addr, ulong *len_ptr, int verify)
{
	DECLARE_GLOBAL_DATA_PTR;
	image_header_t *hdr = &header;
	void	(*entry_point)(bd_t *);

	entry_point = (void (*)(bd_t *)) hdr->ih_ep;

	printf ("## Transferring control to RTEMS (at address %08lx) ...\n",
		(ulong)entry_point);

	SHOW_BOOT_PROGRESS (15);

	/*
	 * RTEMS Parameters:
	 *   r3: ptr to board info data
	 */

	(*entry_point ) ( gd->bd );
}

#if (CONFIG_COMMANDS & CFG_CMD_ELF)
static void
do_bootm_vxworks (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
		  ulong addr, ulong *len_ptr, int verify)
{
	image_header_t *hdr = &header;
	char str[80];

	sprintf(str, "%x", hdr->ih_ep); /* write entry-point into string */
	setenv("loadaddr", str);
	do_bootvx(cmdtp, 0, 0, NULL);
}

static void
do_bootm_qnxelf (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[],
		 ulong addr, ulong *len_ptr, int verify)
{
	image_header_t *hdr = &header;
	char *local_args[2];
	char str[16];

	sprintf(str, "%x", hdr->ih_ep); /* write entry-point into string */
	local_args[0] = argv[0];
	local_args[1] = str;	/* and provide it via the arguments */
	do_bootelf(cmdtp, 0, 2, local_args);
}
#endif /* CFG_CMD_ELF */