Archipelago » qemu

#include "vl.h"

#include "disas.h"

#define ELF_CLASS   ELFCLASS32

#define ELF_DATA    ELFDATA2MSB

#define ELF_ARCH    EM_SPARC

#include "elf.h"

#ifdef BSWAP_NEEDED

static void bswap_ehdr(Elf32_Ehdr *ehdr)

{

    bswap16s(&ehdr->e_type);                        /* Object file type */

    bswap16s(&ehdr->e_machine);                /* Architecture */

    bswap32s(&ehdr->e_version);                /* Object file version */

    bswap32s(&ehdr->e_entry);                /* Entry point virtual address */

    bswap32s(&ehdr->e_phoff);                /* Program header table file offset */

    bswap32s(&ehdr->e_shoff);                /* Section header table file offset */

    bswap32s(&ehdr->e_flags);                /* Processor-specific flags */

    bswap16s(&ehdr->e_ehsize);                /* ELF header size in bytes */

    bswap16s(&ehdr->e_phentsize);                /* Program header table entry size */

    bswap16s(&ehdr->e_phnum);                /* Program header table entry count */

    bswap16s(&ehdr->e_shentsize);                /* Section header table entry size */

    bswap16s(&ehdr->e_shnum);                /* Section header table entry count */

    bswap16s(&ehdr->e_shstrndx);                /* Section header string table index */

}

static void bswap_phdr(Elf32_Phdr *phdr)

{

    bswap32s(&phdr->p_type);                        /* Segment type */

    bswap32s(&phdr->p_offset);                /* Segment file offset */

    bswap32s(&phdr->p_vaddr);                /* Segment virtual address */

    bswap32s(&phdr->p_paddr);                /* Segment physical address */

    bswap32s(&phdr->p_filesz);                /* Segment size in file */

    bswap32s(&phdr->p_memsz);                /* Segment size in memory */

    bswap32s(&phdr->p_flags);                /* Segment flags */

    bswap32s(&phdr->p_align);                /* Segment alignment */

}

static void bswap_shdr(Elf32_Shdr *shdr)

{

    bswap32s(&shdr->sh_name);

    bswap32s(&shdr->sh_type);

    bswap32s(&shdr->sh_flags);

    bswap32s(&shdr->sh_addr);

    bswap32s(&shdr->sh_offset);

    bswap32s(&shdr->sh_size);

    bswap32s(&shdr->sh_link);

    bswap32s(&shdr->sh_info);

    bswap32s(&shdr->sh_addralign);

    bswap32s(&shdr->sh_entsize);

}

static void bswap_sym(Elf32_Sym *sym)

{

    bswap32s(&sym->st_name);

    bswap32s(&sym->st_value);

    bswap32s(&sym->st_size);

    bswap16s(&sym->st_shndx);

}

#else

#define bswap_ehdr(e) do { } while (0)

#define bswap_phdr(e) do { } while (0)

#define bswap_shdr(e) do { } while (0)

#define bswap_sym(e) do { } while (0)

#endif

static int find_phdr(struct elfhdr *ehdr, int fd, struct elf_phdr *phdr, uint32_t type)

{

    int i, retval;

    retval = lseek(fd, ehdr->e_phoff, SEEK_SET);

    if (retval < 0)

        return -1;

    for (i = 0; i < ehdr->e_phnum; i++) {

        retval = read(fd, phdr, sizeof(*phdr));

        if (retval < 0)

            return -1;

        bswap_phdr(phdr);

        if (phdr->p_type == type)

            return 0;

    }

    return -1;

}

static void *find_shdr(struct elfhdr *ehdr, int fd, struct elf_shdr *shdr, uint32_t type)

{

    int i, retval;

    retval = lseek(fd, ehdr->e_shoff, SEEK_SET);

    if (retval < 0)

        return NULL;

    for (i = 0; i < ehdr->e_shnum; i++) {

        retval = read(fd, shdr, sizeof(*shdr));

        if (retval < 0)

            return NULL;

        bswap_shdr(shdr);

        if (shdr->sh_type == type)

            return qemu_malloc(shdr->sh_size);

    }

    return NULL;

}

static int find_strtab(struct elfhdr *ehdr, int fd, struct elf_shdr *shdr, struct elf_shdr *symtab)

{

    int retval;

    retval = lseek(fd, ehdr->e_shoff + sizeof(struct elf_shdr) * symtab->sh_link, SEEK_SET);

    if (retval < 0)

        return -1;

    retval = read(fd, shdr, sizeof(*shdr));

    if (retval < 0)

        return -1;

    bswap_shdr(shdr);

    if (shdr->sh_type == SHT_STRTAB)

        return qemu_malloc(shdr->sh_size);;

    return 0;

}

static int read_program(int fd, struct elf_phdr *phdr, void *dst)

{

    int retval;

    retval = lseek(fd, 0x4000, SEEK_SET);

    if (retval < 0)

        return -1;

    return read(fd, dst, phdr->p_filesz);

}

static int read_section(int fd, struct elf_shdr *s, void *dst)

{

    int retval;

    retval = lseek(fd, s->sh_offset, SEEK_SET);

    if (retval < 0)

        return -1;

    retval = read(fd, dst, s->sh_size);

    if (retval < 0)

        return -1;

    return 0;

}

static void *process_section(struct elfhdr *ehdr, int fd, struct elf_shdr *shdr, uint32_t type)

{

    void *dst;

    dst = find_shdr(ehdr, fd, shdr, type);

    if (!dst)

        goto error;

    if (read_section(fd, shdr, dst))

        goto error;

    return dst;

 error:

    qemu_free(dst);

    return NULL;

}

static void *process_strtab(struct elfhdr *ehdr, int fd, struct elf_shdr *shdr, struct elf_shdr *symtab)

{

    void *dst;

    dst = find_strtab(ehdr, fd, shdr, symtab);

    if (!dst)

        goto error;

    if (read_section(fd, shdr, dst))

        goto error;

    return dst;

 error:

    qemu_free(dst);

    return NULL;

}

static void load_symbols(struct elfhdr *ehdr, int fd)

{

    struct elf_shdr symtab, strtab;

    struct elf_sym *syms;

    int nsyms, i;

    char *str;

    /* Symbol table */

    syms = process_section(ehdr, fd, &symtab, SHT_SYMTAB);

    if (!syms)

        return;

    nsyms = symtab.sh_size / sizeof(struct elf_sym);

    for (i = 0; i < nsyms; i++)

        bswap_sym(&syms[i]);

    /* String table */

    str = process_strtab(ehdr, fd, &strtab, &symtab);

    if (!str)

        goto error_freesyms;

    /* Commit */

    if (disas_symtab)

        qemu_free(disas_symtab); /* XXX Merge with old symbols? */

    if (disas_strtab)

        qemu_free(disas_strtab);

    disas_symtab = syms;

    disas_num_syms = nsyms;

    disas_strtab = str;

    return;

 error_freesyms:

    qemu_free(syms);

    return;

}

int load_elf(const char * filename, uint8_t *addr)

{

    struct elfhdr ehdr;

    struct elf_phdr phdr;

    int retval, fd;

    fd = open(filename, O_RDONLY | O_BINARY);

    if (fd < 0)

        goto error;

    retval = read(fd, &ehdr, sizeof(ehdr));

    if (retval < 0)

        goto error;

    bswap_ehdr(&ehdr);

    if (ehdr.e_ident[0] != 0x7f || ehdr.e_ident[1] != 'E'

        || ehdr.e_ident[2] != 'L' || ehdr.e_ident[3] != 'F'

        || ehdr.e_machine != EM_SPARC)

        goto error;

    if (find_phdr(&ehdr, fd, &phdr, PT_LOAD))

        goto error;

    retval = read_program(fd, &phdr, addr);

    if (retval < 0)

        goto error;

    load_symbols(&ehdr, fd);

    close(fd);

    return retval;

 error:

    close(fd);

    return -1;

}

int load_kernel(const char *filename, uint8_t *addr)

{

    int fd, size;

    fd = open(filename, O_RDONLY | O_BINARY);

    if (fd < 0)

        return -1;

    /* load 32 bit code */

    size = read(fd, addr, 16 * 1024 * 1024);

    if (size < 0)

        goto fail;

    close(fd);

    return size;

 fail:

    close(fd);

    return -1;

}

typedef struct MAGICState {

    uint32_t addr;

    uint32_t saved_addr;

    int magic_state;

    char saved_kfn[1024];

} MAGICState;

static uint32_t magic_mem_readl(void *opaque, target_phys_addr_t addr)

{

    int ret;

    MAGICState *s = opaque;

    if (s->magic_state == 0) {

        ret = load_elf(s->saved_kfn, (uint8_t *)s->saved_addr);

        if (ret < 0)

            ret = load_kernel(s->saved_kfn, (uint8_t *)s->saved_addr);

        if (ret < 0) {

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

                    s->saved_kfn);

        }

        s->magic_state = 1; /* No more magic */

        tb_flush();

        return bswap32(ret);

    }

    return 0;

}

static void magic_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t val)

{

}

static CPUReadMemoryFunc *magic_mem_read[3] = {

    magic_mem_readl,

    magic_mem_readl,

    magic_mem_readl,

};

static CPUWriteMemoryFunc *magic_mem_write[3] = {

    magic_mem_writel,

    magic_mem_writel,

    magic_mem_writel,

};

void magic_init(const char *kfn, int kloadaddr, uint32_t addr)

{

    int magic_io_memory;

    MAGICState *s;

    s = qemu_mallocz(sizeof(MAGICState));

    if (!s)

        return;

    strcpy(s->saved_kfn, kfn);

    s->saved_addr = kloadaddr;

    s->magic_state = 0;

    s->addr = addr;

    magic_io_memory = cpu_register_io_memory(0, magic_mem_read, magic_mem_write, s);

    cpu_register_physical_memory(addr, 4, magic_io_memory);

}