Archipelago » qemu

/*

 * ARM kernel loader.

 *

 * Copyright (c) 2006-2007 CodeSourcery.

 * Written by Paul Brook

 *

 * This code is licensed under the GPL.

 */

#include "config.h"

#include "hw.h"

#include "arm-misc.h"

#include "sysemu/sysemu.h"

#include "boards.h"

#include "loader.h"

#include "elf.h"

#include "sysemu/device_tree.h"

#include "qemu/config-file.h"

#define KERNEL_ARGS_ADDR 0x100

#define KERNEL_LOAD_ADDR 0x00010000

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

static uint32_t bootloader[] = {

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

  0xe59f1004, /* ldr     r1, [pc, #4] */

  0xe59f2004, /* ldr     r2, [pc, #4] */

  0xe59ff004, /* ldr     pc, [pc, #4] */

  0, /* Board ID */

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

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

};

/* Handling for secondary CPU boot in a multicore system.

 * Unlike the uniprocessor/primary CPU boot, this is platform

 * dependent. The default code here is based on the secondary

 * CPU boot protocol used on realview/vexpress boards, with

 * some parameterisation to increase its flexibility.

 * QEMU platform models for which this code is not appropriate

 * should override write_secondary_boot and secondary_cpu_reset_hook

 * instead.

 *

 * This code enables the interrupt controllers for the secondary

 * CPUs and then puts all the secondary CPUs into a loop waiting

 * for an interprocessor interrupt and polling a configurable

 * location for the kernel secondary CPU entry point.

 */

#define DSB_INSN 0xf57ff04f

#define CP15_DSB_INSN 0xee070f9a /* mcr cp15, 0, r0, c7, c10, 4 */

static uint32_t smpboot[] = {

  0xe59f2028, /* ldr r2, gic_cpu_if */

  0xe59f0028, /* ldr r0, startaddr */

  0xe3a01001, /* mov r1, #1 */

  0xe5821000, /* str r1, [r2] - set GICC_CTLR.Enable */

  0xe3a010ff, /* mov r1, #0xff */

  0xe5821004, /* str r1, [r2, 4] - set GIC_PMR.Priority to 0xff */

  DSB_INSN,   /* dsb */

  0xe320f003, /* wfi */

  0xe5901000, /* ldr     r1, [r0] */

  0xe1110001, /* tst     r1, r1 */

  0x0afffffb, /* beq     <wfi> */

  0xe12fff11, /* bx      r1 */

  0,          /* gic_cpu_if: base address of GIC CPU interface */

  0           /* bootreg: Boot register address is held here */

};

static void default_write_secondary(ARMCPU *cpu,

                                    const struct arm_boot_info *info)

{

    int n;

    smpboot[ARRAY_SIZE(smpboot) - 1] = info->smp_bootreg_addr;

    smpboot[ARRAY_SIZE(smpboot) - 2] = info->gic_cpu_if_addr;

    for (n = 0; n < ARRAY_SIZE(smpboot); n++) {

        /* Replace DSB with the pre-v7 DSB if necessary. */

        if (!arm_feature(&cpu->env, ARM_FEATURE_V7) &&

            smpboot[n] == DSB_INSN) {

            smpboot[n] = CP15_DSB_INSN;

        }

        smpboot[n] = tswap32(smpboot[n]);

    }

    rom_add_blob_fixed("smpboot", smpboot, sizeof(smpboot),

                       info->smp_loader_start);

}

static void default_reset_secondary(ARMCPU *cpu,

                                    const struct arm_boot_info *info)

{

    CPUARMState *env = &cpu->env;

    stl_phys_notdirty(info->smp_bootreg_addr, 0);

    env->regs[15] = info->smp_loader_start;

}

#define WRITE_WORD(p, value) do { \

    stl_phys_notdirty(p, value);  \

    p += 4;                       \

} while (0)

static void set_kernel_args(const struct arm_boot_info *info)

{

    int initrd_size = info->initrd_size;

    hwaddr base = info->loader_start;

    hwaddr p;

    p = base + KERNEL_ARGS_ADDR;

    /* ATAG_CORE */

    WRITE_WORD(p, 5);

    WRITE_WORD(p, 0x54410001);

    WRITE_WORD(p, 1);

    WRITE_WORD(p, 0x1000);

    WRITE_WORD(p, 0);

    /* ATAG_MEM */

    /* TODO: handle multiple chips on one ATAG list */

    WRITE_WORD(p, 4);

    WRITE_WORD(p, 0x54410002);

    WRITE_WORD(p, info->ram_size);

    WRITE_WORD(p, info->loader_start);

    if (initrd_size) {

        /* ATAG_INITRD2 */

        WRITE_WORD(p, 4);

        WRITE_WORD(p, 0x54420005);

        WRITE_WORD(p, info->initrd_start);

        WRITE_WORD(p, initrd_size);

    }

    if (info->kernel_cmdline && *info->kernel_cmdline) {

        /* ATAG_CMDLINE */

        int cmdline_size;

        cmdline_size = strlen(info->kernel_cmdline);

        cpu_physical_memory_write(p + 8, (void *)info->kernel_cmdline,

                                  cmdline_size + 1);

        cmdline_size = (cmdline_size >> 2) + 1;

        WRITE_WORD(p, cmdline_size + 2);

        WRITE_WORD(p, 0x54410009);

        p += cmdline_size * 4;

    }

    if (info->atag_board) {

        /* ATAG_BOARD */

        int atag_board_len;

        uint8_t atag_board_buf[0x1000];

        atag_board_len = (info->atag_board(info, atag_board_buf) + 3) & ~3;

        WRITE_WORD(p, (atag_board_len + 8) >> 2);

        WRITE_WORD(p, 0x414f4d50);

        cpu_physical_memory_write(p, atag_board_buf, atag_board_len);

        p += atag_board_len;

    }

    /* ATAG_END */

    WRITE_WORD(p, 0);

    WRITE_WORD(p, 0);

}

static void set_kernel_args_old(const struct arm_boot_info *info)

{

    hwaddr p;

    const char *s;

    int initrd_size = info->initrd_size;

    hwaddr base = info->loader_start;

    /* see linux/include/asm-arm/setup.h */

    p = base + KERNEL_ARGS_ADDR;

    /* page_size */

    WRITE_WORD(p, 4096);

    /* nr_pages */

    WRITE_WORD(p, info->ram_size / 4096);

    /* ramdisk_size */

    WRITE_WORD(p, 0);

#define FLAG_READONLY        1

#define FLAG_RDLOAD        4

#define FLAG_RDPROMPT        8

    /* flags */

    WRITE_WORD(p, FLAG_READONLY | FLAG_RDLOAD | FLAG_RDPROMPT);

    /* rootdev */

    WRITE_WORD(p, (31 << 8) | 0);        /* /dev/mtdblock0 */

    /* video_num_cols */

    WRITE_WORD(p, 0);

    /* video_num_rows */

    WRITE_WORD(p, 0);

    /* video_x */

    WRITE_WORD(p, 0);

    /* video_y */

    WRITE_WORD(p, 0);

    /* memc_control_reg */

    WRITE_WORD(p, 0);

    /* unsigned char sounddefault */

    /* unsigned char adfsdrives */

    /* unsigned char bytes_per_char_h */

    /* unsigned char bytes_per_char_v */

    WRITE_WORD(p, 0);

    /* pages_in_bank[4] */

    WRITE_WORD(p, 0);

    WRITE_WORD(p, 0);

    WRITE_WORD(p, 0);

    WRITE_WORD(p, 0);

    /* pages_in_vram */

    WRITE_WORD(p, 0);

    /* initrd_start */

    if (initrd_size) {

        WRITE_WORD(p, info->initrd_start);

    } else {

        WRITE_WORD(p, 0);

    }

    /* initrd_size */

    WRITE_WORD(p, initrd_size);

    /* rd_start */

    WRITE_WORD(p, 0);

    /* system_rev */

    WRITE_WORD(p, 0);

    /* system_serial_low */

    WRITE_WORD(p, 0);

    /* system_serial_high */

    WRITE_WORD(p, 0);

    /* mem_fclk_21285 */

    WRITE_WORD(p, 0);

    /* zero unused fields */

    while (p < base + KERNEL_ARGS_ADDR + 256 + 1024) {

        WRITE_WORD(p, 0);

    }

    s = info->kernel_cmdline;

    if (s) {

        cpu_physical_memory_write(p, (void *)s, strlen(s) + 1);

    } else {

        WRITE_WORD(p, 0);

    }

}

static int load_dtb(hwaddr addr, const struct arm_boot_info *binfo)

{

#ifdef CONFIG_FDT

    uint32_t *mem_reg_property;

    uint32_t mem_reg_propsize;

    void *fdt = NULL;

    char *filename;

    int size, rc;

    uint32_t acells, scells, hival;

    filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, binfo->dtb_filename);

    if (!filename) {

        fprintf(stderr, "Couldn't open dtb file %s\n", binfo->dtb_filename);

        return -1;

    }

    fdt = load_device_tree(filename, &size);

    if (!fdt) {

        fprintf(stderr, "Couldn't open dtb file %s\n", filename);

        g_free(filename);

        return -1;

    }

    g_free(filename);

    acells = qemu_devtree_getprop_cell(fdt, "/", "#address-cells");

    scells = qemu_devtree_getprop_cell(fdt, "/", "#size-cells");

    if (acells == 0 || scells == 0) {

        fprintf(stderr, "dtb file invalid (#address-cells or #size-cells 0)\n");

        return -1;

    }

    mem_reg_propsize = acells + scells;

    mem_reg_property = g_new0(uint32_t, mem_reg_propsize);

    mem_reg_property[acells - 1] = cpu_to_be32(binfo->loader_start);

    hival = cpu_to_be32(binfo->loader_start >> 32);

    if (acells > 1) {

        mem_reg_property[acells - 2] = hival;

    } else if (hival != 0) {

        fprintf(stderr, "qemu: dtb file not compatible with "

                "RAM start address > 4GB\n");

        exit(1);

    }

    mem_reg_property[acells + scells - 1] = cpu_to_be32(binfo->ram_size);

    hival = cpu_to_be32(binfo->ram_size >> 32);

    if (scells > 1) {

        mem_reg_property[acells + scells - 2] = hival;

    } else if (hival != 0) {

        fprintf(stderr, "qemu: dtb file not compatible with "

                "RAM size > 4GB\n");

        exit(1);

    }

    rc = qemu_devtree_setprop(fdt, "/memory", "reg", mem_reg_property,

                              mem_reg_propsize * sizeof(uint32_t));

    if (rc < 0) {

        fprintf(stderr, "couldn't set /memory/reg\n");

    }

    if (binfo->kernel_cmdline && *binfo->kernel_cmdline) {

        rc = qemu_devtree_setprop_string(fdt, "/chosen", "bootargs",

                                          binfo->kernel_cmdline);

        if (rc < 0) {

            fprintf(stderr, "couldn't set /chosen/bootargs\n");

        }

    }

    if (binfo->initrd_size) {

        rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-start",

                binfo->initrd_start);

        if (rc < 0) {

            fprintf(stderr, "couldn't set /chosen/linux,initrd-start\n");

        }

        rc = qemu_devtree_setprop_cell(fdt, "/chosen", "linux,initrd-end",

                    binfo->initrd_start + binfo->initrd_size);

        if (rc < 0) {

            fprintf(stderr, "couldn't set /chosen/linux,initrd-end\n");

        }

    }

    cpu_physical_memory_write(addr, fdt, size);

    return 0;

#else

    fprintf(stderr, "Device tree requested, "

                "but qemu was compiled without fdt support\n");

    return -1;

#endif

}

static void do_cpu_reset(void *opaque)

{

    ARMCPU *cpu = opaque;

    CPUARMState *env = &cpu->env;

    const struct arm_boot_info *info = env->boot_info;

    cpu_reset(CPU(cpu));

    if (info) {

        if (!info->is_linux) {

            /* Jump to the entry point.  */

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

            env->thumb = info->entry & 1;

        } else {

            if (env == first_cpu) {

                env->regs[15] = info->loader_start;

                if (!info->dtb_filename) {

                    if (old_param) {

                        set_kernel_args_old(info);

                    } else {

                        set_kernel_args(info);

                    }

                }

            } else {

                info->secondary_cpu_reset_hook(cpu, info);

            }

        }

    }

}

void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)

{

    CPUARMState *env = &cpu->env;

    int kernel_size;

    int initrd_size;

    int n;

    int is_linux = 0;

    uint64_t elf_entry;

    hwaddr entry;

    int big_endian;

    QemuOpts *machine_opts;

    /* Load the kernel.  */

    if (!info->kernel_filename) {

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

        exit(1);

    }

    machine_opts = qemu_opts_find(qemu_find_opts("machine"), 0);

    if (machine_opts) {

        info->dtb_filename = qemu_opt_get(machine_opts, "dtb");

    } else {

        info->dtb_filename = NULL;

    }

    if (!info->secondary_cpu_reset_hook) {

        info->secondary_cpu_reset_hook = default_reset_secondary;

    }

    if (!info->write_secondary_boot) {

        info->write_secondary_boot = default_write_secondary;

    }

    if (info->nb_cpus == 0)

        info->nb_cpus = 1;

#ifdef TARGET_WORDS_BIGENDIAN

    big_endian = 1;

#else

    big_endian = 0;

#endif

    /* We want to put the initrd far enough into RAM that when the

     * kernel is uncompressed it will not clobber the initrd. However

     * on boards without much RAM we must ensure that we still leave

     * enough room for a decent sized initrd, and on boards with large

     * amounts of RAM we must avoid the initrd being so far up in RAM

     * that it is outside lowmem and inaccessible to the kernel.

     * So for boards with less  than 256MB of RAM we put the initrd

     * halfway into RAM, and for boards with 256MB of RAM or more we put

     * the initrd at 128MB.

     */

    info->initrd_start = info->loader_start +

        MIN(info->ram_size / 2, 128 * 1024 * 1024);

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

    kernel_size = load_elf(info->kernel_filename, NULL, NULL, &elf_entry,

                           NULL, NULL, big_endian, ELF_MACHINE, 1);

    entry = elf_entry;

    if (kernel_size < 0) {

        kernel_size = load_uimage(info->kernel_filename, &entry, NULL,

                                  &is_linux);

    }

    if (kernel_size < 0) {

        entry = info->loader_start + KERNEL_LOAD_ADDR;

        kernel_size = load_image_targphys(info->kernel_filename, entry,

                                          info->ram_size - KERNEL_LOAD_ADDR);

        is_linux = 1;

    }

    if (kernel_size < 0) {

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

                info->kernel_filename);

        exit(1);

    }

    info->entry = entry;

    if (is_linux) {

        if (info->initrd_filename) {

            initrd_size = load_image_targphys(info->initrd_filename,

                                              info->initrd_start,

                                              info->ram_size -

                                              info->initrd_start);

            if (initrd_size < 0) {

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

                        info->initrd_filename);

                exit(1);

            }

        } else {

            initrd_size = 0;

        }

        info->initrd_size = initrd_size;

        bootloader[4] = info->board_id;

        /* for device tree boot, we pass the DTB directly in r2. Otherwise

         * we point to the kernel args.

         */

        if (info->dtb_filename) {

            /* Place the DTB after the initrd in memory */

            hwaddr dtb_start = TARGET_PAGE_ALIGN(info->initrd_start +

                                                 initrd_size);

            if (load_dtb(dtb_start, info)) {

                exit(1);

            }

            bootloader[5] = dtb_start;

        } else {

            bootloader[5] = info->loader_start + KERNEL_ARGS_ADDR;

            if (info->ram_size >= (1ULL << 32)) {

                fprintf(stderr, "qemu: RAM size must be less than 4GB to boot"

                        " Linux kernel using ATAGS (try passing a device tree"

                        " using -dtb)\n");

                exit(1);

            }

        }

        bootloader[6] = entry;

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

            bootloader[n] = tswap32(bootloader[n]);

        }

        rom_add_blob_fixed("bootloader", bootloader, sizeof(bootloader),

                           info->loader_start);

        if (info->nb_cpus > 1) {

            info->write_secondary_boot(cpu, info);

        }

    }

    info->is_linux = is_linux;

    for (; env; env = env->next_cpu) {

        cpu = arm_env_get_cpu(env);

        env->boot_info = info;

        qemu_register_reset(do_cpu_reset, cpu);

    }

}