Archipelago » qemu

/* 

 * ARM kernel loader.

 *

 * Copyright (c) 2006 CodeSourcery.

 * Written by Paul Brook

 *

 * This code is licenced under the GPL.

 */

#include "vl.h"

#define KERNEL_ARGS_ADDR 0x100

#define KERNEL_LOAD_ADDR 0x00010000

#define INITRD_LOAD_ADDR 0x00800000

/* The worlds second smallest bootloader.  Set r0-r2, then jump to kernel.  */

static uint32_t bootloader[] = {

  0xe3a00000, /* mov     r0, #0 */

  0xe3a01000, /* mov     r1, #0x?? */

  0xe3811c00, /* orr     r1, r1, #0x??00 */

  0xe59f2000, /* ldr     r2, [pc, #0] */

  0xe59ff000, /* ldr     pc, [pc, #0] */

  0, /* Address of kernel args.  Set by integratorcp_init.  */

  0  /* Kernel entry point.  Set by integratorcp_init.  */

};

static void main_cpu_reset(void *opaque)

{

    CPUState *env = opaque;

    cpu_reset(env);

    if (env->kernel_filename)

        arm_load_kernel(env, env->ram_size, env->kernel_filename, 

                        env->kernel_cmdline, env->initrd_filename, 

                        env->board_id, env->loader_start);

}

static void set_kernel_args(uint32_t ram_size, int initrd_size,

                            const char *kernel_cmdline,

                            target_phys_addr_t loader_start)

{

    uint32_t *p;

    p = (uint32_t *)(phys_ram_base + KERNEL_ARGS_ADDR);

    /* ATAG_CORE */

    stl_raw(p++, 5);

    stl_raw(p++, 0x54410001);

    stl_raw(p++, 1);

    stl_raw(p++, 0x1000);

    stl_raw(p++, 0);

    /* ATAG_MEM */

    stl_raw(p++, 4);

    stl_raw(p++, 0x54410002);

    stl_raw(p++, ram_size);

    stl_raw(p++, loader_start);

    if (initrd_size) {

        /* ATAG_INITRD2 */

        stl_raw(p++, 4);

        stl_raw(p++, 0x54420005);

        stl_raw(p++, loader_start + INITRD_LOAD_ADDR);

        stl_raw(p++, initrd_size);

    }

    if (kernel_cmdline && *kernel_cmdline) {

        /* ATAG_CMDLINE */

        int cmdline_size;

        cmdline_size = strlen(kernel_cmdline);

        memcpy (p + 2, kernel_cmdline, cmdline_size + 1);

        cmdline_size = (cmdline_size >> 2) + 1;

        stl_raw(p++, cmdline_size + 2);

        stl_raw(p++, 0x54410009);

        p += cmdline_size;

    }

    /* ATAG_END */

    stl_raw(p++, 0);

    stl_raw(p++, 0);

}

void arm_load_kernel(CPUState *env, int ram_size, const char *kernel_filename,

                     const char *kernel_cmdline, const char *initrd_filename,

                     int board_id, target_phys_addr_t loader_start)

{

    int kernel_size;

    int initrd_size;

    int n;

    int is_linux = 0;

    uint64_t elf_entry;

    target_ulong entry;

    /* Load the kernel.  */

    if (!kernel_filename) {

        fprintf(stderr, "Kernel image must be specified\n");

        exit(1);

    }

    if (!env->kernel_filename) {

        env->ram_size = ram_size;

        env->kernel_filename = kernel_filename;

        env->kernel_cmdline = kernel_cmdline;

        env->initrd_filename = initrd_filename;

        env->board_id = board_id;

        env->loader_start = loader_start;

        qemu_register_reset(main_cpu_reset, env);

    }

    /* Assume that raw images are linux kernels, and ELF images are not.  */

    kernel_size = load_elf(kernel_filename, 0, &elf_entry, NULL, NULL);

    entry = elf_entry;

    if (kernel_size < 0) {

        kernel_size = load_uboot(kernel_filename, &entry, &is_linux);

    }

    if (kernel_size < 0) {

        kernel_size = load_image(kernel_filename,

                                 phys_ram_base + KERNEL_LOAD_ADDR);

        entry = loader_start + KERNEL_LOAD_ADDR;

        is_linux = 1;

    }

    if (kernel_size < 0) {

        fprintf(stderr, "qemu: could not load kernel '%s'\n", kernel_filename);

        exit(1);

    }

    if (!is_linux) {

        /* Jump to the entry point.  */

        env->regs[15] = entry & 0xfffffffe;

        env->thumb = entry & 1;

    } else {

        if (initrd_filename) {

            initrd_size = load_image(initrd_filename,

                                     phys_ram_base + INITRD_LOAD_ADDR);

            if (initrd_size < 0) {

                fprintf(stderr, "qemu: could not load initrd '%s'\n",

                        initrd_filename);

                exit(1);

            }

        } else {

            initrd_size = 0;

        }

        bootloader[1] |= board_id & 0xff;

        bootloader[2] |= (board_id >> 8) & 0xff;

        bootloader[5] = loader_start + KERNEL_ARGS_ADDR;

        bootloader[6] = entry;

        for (n = 0; n < sizeof(bootloader) / 4; n++)

            stl_raw(phys_ram_base + (n * 4), bootloader[n]);

        set_kernel_args(ram_size, initrd_size, kernel_cmdline, loader_start);

    }

}