sx551 failure to boot on Backfire

/* output:
===========================================================
 TI ADSL AR7300 Loader 0.71.4 build Oct 18 2005 11:13:40
                 Broad Net Technology, INC.
===========================================================
MXIC MX29LV160B bottom boot 16-bit mode found

Copying boot params.....DONE

Flash Checking  Passed.

Unzipping  web at 0x94f30000 ... [LZMA] done
Unzipping code at 0x94000000 ... [LZMA] doneLinux version 2.6.32.27 (peter@penguin) (gcc version 4.3.3 (GCC) ) #7 Tue Mar 27 11:35:39 CEST 2012
bootconsole [early0] enabled
CPU revision is: 00018448 (MIPS 4KEc)
TI AR7 (TNETD7300), ID: 0x0005, Revision: 0x26
Determined physical RAM map:
boot_mem_map.nr_map = 1
 memory: 02000000 @ 14000000 (usable)
exiting print_memory_map
Begin strlcpy to 00000001 for

bootmem_init
Initrd not found or empty - disabling initrd
sparse_init
paging init
Zone PFN ranges:
  Normal   0x00014000 -> 0x00016000
Movable zone start PFN for each node
early_node_map[1] active PFN ranges
    0: 0x00014000 -> 0x00016000
end of arch_mem_init
resource init
plat smp setup
end of setup_arch

*/


/* from arch/mips/kernel/setup.c:558 */
void __init setup_arch(char **cmdline_p)
{
        cpu_probe();
        prom_init();

#ifdef CONFIG_EARLY_PRINTK
        setup_early_printk();
#endif
        cpu_report();
        check_bugs_early();

#if defined(CONFIG_VT)
#if defined(CONFIG_VGA_CONSOLE)
        conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
        conswitchp = &dummy_con;
#endif
#endif

        arch_mem_init(cmdline_p);

        pr_info("resource init\n");
        resource_init();
        pr_info("plat smp setup\n");
        plat_smp_setup();
        pr_info("end of setup_arch\n");
}




/* caller, init/main.c:512 */
asmlinkage void __init start_kernel(void)
{
        char * command_line;
        extern struct kernel_param __start___param[], __stop___param[];

        smp_setup_processor_id();

        /*
         * Need to run as early as possible, to initialize the
         * lockdep hash:
         */
        lockdep_init();
        debug_objects_early_init();

        /*
         * Set up the the initial canary ASAP:
         */
        boot_init_stack_canary();

        cgroup_init_early();

        local_irq_disable();
        early_boot_irqs_off();
        early_init_irq_lock_class();

/*
 * Interrupts are still disabled. Do necessary setups, then
 * enable them
 */
        lock_kernel();
        tick_init();
        boot_cpu_init();
        page_address_init();
        printk(KERN_NOTICE "%s", linux_banner);
        setup_arch(&command_line);
        pr_info("mm_init_owner");
        pr_info("(%p, %p)\n", &init_mm, &init_task);
        mm_init_owner(&init_mm, &init_task);
        pr_info("setup_command_line\n");
        setup_command_line(command_line);
        pr_info("setup_nr_cpu_ids\n");
        setup_nr_cpu_ids();
        pr_info("setup_per_cpu_areas\n");
        setup_per_cpu_areas();
        pr_info("smp_prepare_boot_cpu\n");
        smp_prepare_boot_cpu(); /* arch-specific boot-cpu hooks */

        pr_info("build_all_zonelists\n");
        build_all_zonelists();
        pr_info("page_alloc_init\n");
        page_alloc_init();