source: SVN/rincon/u-boot/common/cmd_elf.c @ 55

/*
 * Copyright (c) 2001 William L. Pitts
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are freely
 * permitted provided that the above copyright notice and this
 * paragraph and the following disclaimer are duplicated in all
 * such forms.
 *
 * This software is provided "AS IS" and without any express or
 * implied warranties, including, without limitation, the implied
 * warranties of merchantability and fitness for a particular
 * purpose.
 */

#include <common.h>
#include <command.h>
#include <linux/ctype.h>
#include <net.h>
#include <elf.h>

#if defined(CONFIG_WALNUT) || defined(CFG_VXWORKS_MAC_PTR)
DECLARE_GLOBAL_DATA_PTR;
#endif

#ifndef MAX
#define MAX(a,b) ((a) > (b) ? (a) : (b))
#endif

int valid_elf_image (unsigned long addr);
unsigned long load_elf_image (unsigned long addr);

/* Allow ports to override the default behavior */
__attribute__((weak))
unsigned long do_bootelf_exec (ulong (*entry)(int, char *[]), int argc, char *argv[])
{
        unsigned long ret;

        /*
         * QNX images require the data cache is disabled.
         * Data cache is already flushed, so just turn it off.
         */
        int dcache = dcache_status ();
        if (dcache)
                dcache_disable ();

        /*
         * pass address parameter as argv[0] (aka command name),
         * and all remaining args
         */
        ret = entry (argc, argv);

        if (dcache)
                dcache_enable ();

        return ret;
}

/* ======================================================================
 * Interpreter command to boot an arbitrary ELF image from memory.
 * ====================================================================== */
int do_bootelf (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
        unsigned long addr;             /* Address of the ELF image     */
        unsigned long rc;               /* Return value from user code  */

        /* -------------------------------------------------- */
        int rcode = 0;

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

        if (!valid_elf_image (addr))
                return 1;

        addr = load_elf_image (addr);

        printf ("## Starting application at 0x%08lx ...\n", addr);

        /*
         * pass address parameter as argv[0] (aka command name),
         * and all remaining args
         */
        rc = do_bootelf_exec ((void *)addr, argc - 1, argv + 1);
        if (rc != 0)
                rcode = 1;

        printf ("## Application terminated, rc = 0x%lx\n", rc);
        return rcode;
}

/* ======================================================================
 * Interpreter command to boot VxWorks from a memory image.  The image can
 * be either an ELF image or a raw binary.  Will attempt to setup the
 * bootline and other parameters correctly.
 * ====================================================================== */
int do_bootvx (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
        unsigned long addr;             /* Address of image            */
        unsigned long bootaddr;         /* Address to put the bootline */
        char *bootline;                 /* Text of the bootline        */
        char *tmp;                      /* Temporary char pointer      */

#if defined(CONFIG_4xx) || defined(CONFIG_IOP480)
        char build_buf[80];             /* Buffer for building the bootline */
#endif
        /* -------------------------------------------------- */

        /*
         * Check the loadaddr variable.
         * If we don't know where the image is then we're done.
         */

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

#if defined(CONFIG_CMD_NET)
        /* Check to see if we need to tftp the image ourselves before starting */

        if ((argc == 2) && (strcmp (argv[1], "tftp") == 0)) {
                if (NetLoop (TFTP) <= 0)
                        return 1;
                printf ("Automatic boot of VxWorks image at address 0x%08lx ... \n", addr);
        }
#endif

        /* This should equate
         * to NV_RAM_ADRS + NV_BOOT_OFFSET + NV_ENET_OFFSET
         * from the VxWorks BSP header files.
         * This will vary from board to board
         */

#if defined(CONFIG_WALNUT)
        tmp = (char *) CFG_NVRAM_BASE_ADDR + 0x500;
        memcpy ((char *) tmp, (char *) &gd->bd->bi_enetaddr[3], 3);
#elif defined(CFG_VXWORKS_MAC_PTR)
        tmp = (char *) CFG_VXWORKS_MAC_PTR;
        memcpy ((char *) tmp, (char *) &gd->bd->bi_enetaddr[0], 6);
#else
        puts ("## Ethernet MAC address not copied to NV RAM\n");
#endif

        /*
         * Use bootaddr to find the location in memory that VxWorks
         * will look for the bootline string. The default value for
         * PowerPC is LOCAL_MEM_LOCAL_ADRS + BOOT_LINE_OFFSET which
         * defaults to 0x4200
         */

        if ((tmp = getenv ("bootaddr")) == NULL)
                bootaddr = 0x4200;
        else
                bootaddr = simple_strtoul (tmp, NULL, 16);

        /*
         * Check to see if the bootline is defined in the 'bootargs'
         * parameter. If it is not defined, we may be able to
         * construct the info
         */

        if ((bootline = getenv ("bootargs")) != NULL) {
                memcpy ((void *) bootaddr, bootline, MAX(strlen(bootline), 255));
                flush_cache (bootaddr, MAX(strlen(bootline), 255));
        } else {
#if defined(CONFIG_4xx)
                sprintf (build_buf, "ibmEmac(0,0)");

                if ((tmp = getenv ("hostname")) != NULL) {
                        sprintf (&build_buf[strlen (build_buf - 1)],
                                "host:%s ", tmp);
                } else {
                        sprintf (&build_buf[strlen (build_buf - 1)],
                                ": ");
                }

                if ((tmp = getenv ("ipaddr")) != NULL) {
                        sprintf (&build_buf[strlen (build_buf - 1)],
                                "e=%s ", tmp);
                }
                memcpy ((void *)bootaddr, build_buf, MAX(strlen(build_buf), 255));
                flush_cache (bootaddr, MAX(strlen(build_buf), 255));
#elif defined(CONFIG_IOP480)
                sprintf (build_buf, "dc(0,0)");

                if ((tmp = getenv ("hostname")) != NULL) {
                        sprintf (&build_buf[strlen (build_buf - 1)],
                                "host:%s ", tmp);
                } else {
                        sprintf (&build_buf[strlen (build_buf - 1)],
                                ": ");
                }

                if ((tmp = getenv ("ipaddr")) != NULL) {
                        sprintf (&build_buf[strlen (build_buf - 1)],
                                "e=%s ", tmp);
                }
                memcpy ((void *) bootaddr, build_buf, MAX(strlen(build_buf), 255));
                flush_cache (bootaddr, MAX(strlen(build_buf), 255));
#else

                /*
                 * I'm not sure what the device should be for other
                 * PPC flavors, the hostname and ipaddr should be ok
                 * to just copy
                 */

                puts ("No bootargs defined\n");
                return 1;
#endif
        }

        /*
         * If the data at the load address is an elf image, then
         * treat it like an elf image. Otherwise, assume that it is a
         * binary image
         */

        if (valid_elf_image (addr)) {
                addr = load_elf_image (addr);
        } else {
                puts ("## Not an ELF image, assuming binary\n");
                /* leave addr as load_addr */
        }

        printf ("## Using bootline (@ 0x%lx): %s\n", bootaddr,
                        (char *) bootaddr);
        printf ("## Starting vxWorks at 0x%08lx ...\n", addr);

        ((void (*)(void)) addr) ();

        puts ("## vxWorks terminated\n");
        return 1;
}

/* ======================================================================
 * Determine if a valid ELF image exists at the given memory location.
 * First looks at the ELF header magic field, the makes sure that it is
 * executable and makes sure that it is for a PowerPC.
 * ====================================================================== */
int valid_elf_image (unsigned long addr)
{
        Elf32_Ehdr *ehdr;               /* Elf header structure pointer */

        /* -------------------------------------------------- */

        ehdr = (Elf32_Ehdr *) addr;

        if (!IS_ELF (*ehdr)) {
                printf ("## No elf image at address 0x%08lx\n", addr);
                return 0;
        }

        if (ehdr->e_type != ET_EXEC) {
                printf ("## Not a 32-bit elf image at address 0x%08lx\n",
                        addr);
                return 0;
        }

#if 0
        if (ehdr->e_machine != EM_PPC) {
                printf ("## Not a PowerPC elf image at address 0x%08lx\n",
                        addr);
                return 0;
        }
#endif

        return 1;
}


/* ======================================================================
 * A very simple elf loader, assumes the image is valid, returns the
 * entry point address.
 * ====================================================================== */
unsigned long load_elf_image (unsigned long addr)
{
        Elf32_Ehdr *ehdr;               /* Elf header structure pointer     */
        Elf32_Shdr *shdr;               /* Section header structure pointer */
        unsigned char *strtab = 0;      /* String table pointer             */
        unsigned char *image;           /* Binary image pointer             */
        int i;                          /* Loop counter                     */

        /* -------------------------------------------------- */

        ehdr = (Elf32_Ehdr *) addr;

        /* Find the section header string table for output info */
        shdr = (Elf32_Shdr *) (addr + ehdr->e_shoff +
                               (ehdr->e_shstrndx * sizeof (Elf32_Shdr)));

        if (shdr->sh_type == SHT_STRTAB)
                strtab = (unsigned char *) (addr + shdr->sh_offset);

        /* Load each appropriate section */
        for (i = 0; i < ehdr->e_shnum; ++i) {
                shdr = (Elf32_Shdr *) (addr + ehdr->e_shoff +
                                       (i * sizeof (Elf32_Shdr)));

                if (!(shdr->sh_flags & SHF_ALLOC)
                   || shdr->sh_addr == 0 || shdr->sh_size == 0) {
                        continue;
                }

                if (strtab) {
                        printf ("%sing %s @ 0x%08lx (%ld bytes)\n",
                                (shdr->sh_type == SHT_NOBITS) ?
                                        "Clear" : "Load",
                                &strtab[shdr->sh_name],
                                (unsigned long) shdr->sh_addr,
                                (long) shdr->sh_size);
                }

                if (shdr->sh_type == SHT_NOBITS) {
                        memset ((void *)shdr->sh_addr, 0, shdr->sh_size);
                } else {
                        image = (unsigned char *) addr + shdr->sh_offset;
                        memcpy ((void *) shdr->sh_addr,
                                (const void *) image,
                                shdr->sh_size);
                }
                flush_cache (shdr->sh_addr, shdr->sh_size);
        }

        return ehdr->e_entry;
}

/* ====================================================================== */
U_BOOT_CMD(
        bootelf,      2,      0,      do_bootelf,
        "bootelf - Boot from an ELF image in memory\n",
        " [address] - load address of ELF image.\n"
);

U_BOOT_CMD(
        bootvx,      2,      0,      do_bootvx,
        "bootvx  - Boot vxWorks from an ELF image\n",
        " [address] - load address of vxWorks ELF image.\n"
);