diff options
| -rw-r--r-- | hw/pc.c | 304 | ||||
| -rw-r--r-- | pc-bios/Makefile | 7 |
2 files changed, 222 insertions, 89 deletions
@@ -31,10 +31,6 @@ #define VGABIOS_CIRRUS_FILENAME "vgabios-cirrus.bin" #define LINUX_BOOT_FILENAME "linux_boot.bin" -#define KERNEL_LOAD_ADDR 0x00100000 -#define MAX_INITRD_LOAD_ADDR 0x38000000 -#define KERNEL_PARAMS_ADDR 0x00090000 -#define KERNEL_CMDLINE_ADDR 0x00099000 /* Leave a chunk of memory at the top of RAM for the BIOS ACPI tables. */ #define ACPI_DATA_SIZE 0x10000 @@ -350,6 +346,61 @@ void bochs_bios_init(void) register_ioport_write(0x503, 1, 1, bochs_bios_write, NULL); } +/* Generate an initial boot sector which sets state and jump to + a specified vector */ +static int generate_bootsect(uint32_t gpr[8], uint16_t segs[6], uint16_t ip) +{ + uint8_t bootsect[512], *p; + int i; + + if (bs_table[0] == NULL) { + fprintf(stderr, "A disk image must be given for 'hda' when booting " + "a Linux kernel\n"); + exit(1); + } + + memset(bootsect, 0, sizeof(bootsect)); + + /* Copy the MSDOS partition table if possible */ + bdrv_read(bs_table[0], 0, bootsect, 1); + + /* Make sure we have a partition signature */ + bootsect[510] = 0x55; + bootsect[511] = 0xaa; + + /* Actual code */ + p = bootsect; + *p++ = 0xfa; /* CLI */ + *p++ = 0xfc; /* CLD */ + + for (i = 0; i < 6; i++) { + if (i == 1) /* Skip CS */ + continue; + + *p++ = 0xb8; /* MOV AX,imm16 */ + *p++ = segs[i]; + *p++ = segs[i] >> 8; + *p++ = 0x8e; /* MOV <seg>,AX */ + *p++ = 0xc0 + (i << 3); + } + + for (i = 0; i < 8; i++) { + *p++ = 0x66; /* 32-bit operand size */ + *p++ = 0xb8 + i; /* MOV <reg>,imm32 */ + *p++ = gpr[i]; + *p++ = gpr[i] >> 8; + *p++ = gpr[i] >> 16; + *p++ = gpr[i] >> 24; + } + + *p++ = 0xea; /* JMP FAR */ + *p++ = ip; /* IP */ + *p++ = ip >> 8; + *p++ = segs[1]; /* CS */ + *p++ = segs[1] >> 8; + + bdrv_set_boot_sector(bs_table[0], bootsect, sizeof(bootsect)); +} int load_kernel(const char *filename, uint8_t *addr, uint8_t *real_addr) @@ -370,7 +421,7 @@ int load_kernel(const char *filename, uint8_t *addr, if (read(fd, real_addr + 512, setup_sects * 512) != setup_sects * 512) goto fail; - + /* load 32 bit code */ size = read(fd, addr, 16 * 1024 * 1024); if (size < 0) @@ -382,6 +433,169 @@ int load_kernel(const char *filename, uint8_t *addr, return -1; } +static long get_file_size(FILE *f) +{ + long where, size; + + /* XXX: on Unix systems, using fstat() probably makes more sense */ + + where = ftell(f); + fseek(f, 0, SEEK_END); + size = ftell(f); + fseek(f, where, SEEK_SET); + + return size; +} + +static void load_linux(const char *kernel_filename, + const char *initrd_filename, + const char *kernel_cmdline) +{ + uint16_t protocol; + uint32_t gpr[8]; + uint16_t seg[6]; + uint16_t real_seg; + int setup_size, kernel_size, initrd_size, cmdline_size; + uint32_t initrd_max; + uint8_t header[1024]; + uint8_t *real_addr, *prot_addr, *cmdline_addr, *initrd_addr; + FILE *f, *fi; + + /* Align to 16 bytes as a paranoia measure */ + cmdline_size = (strlen(kernel_cmdline)+16) & ~15; + + /* load the kernel header */ + f = fopen(kernel_filename, "rb"); + if (!f || !(kernel_size = get_file_size(f)) || + fread(header, 1, 1024, f) != 1024) { + fprintf(stderr, "qemu: could not load kernel '%s'\n", + kernel_filename); + exit(1); + } + + /* kernel protocol version */ + fprintf(stderr, "header magic: %#x\n", ldl_p(header+0x202)); + if (ldl_p(header+0x202) == 0x53726448) + protocol = lduw_p(header+0x206); + else + protocol = 0; + + if (protocol < 0x200 || !(header[0x211] & 0x01)) { + /* Low kernel */ + real_addr = phys_ram_base + 0x90000; + cmdline_addr = phys_ram_base + 0x9a000 - cmdline_size; + prot_addr = phys_ram_base + 0x10000; + } else if (protocol < 0x202) { + /* High but ancient kernel */ + real_addr = phys_ram_base + 0x90000; + cmdline_addr = phys_ram_base + 0x9a000 - cmdline_size; + prot_addr = phys_ram_base + 0x100000; + } else { + /* High and recent kernel */ + real_addr = phys_ram_base + 0x10000; + cmdline_addr = phys_ram_base + 0x20000; + prot_addr = phys_ram_base + 0x100000; + } + + fprintf(stderr, + "qemu: real_addr = %#zx\n" + "qemu: cmdline_addr = %#zx\n" + "qemu: prot_addr = %#zx\n", + real_addr-phys_ram_base, + cmdline_addr-phys_ram_base, + prot_addr-phys_ram_base); + + /* highest address for loading the initrd */ + if (protocol >= 0x203) + initrd_max = ldl_p(header+0x22c); + else + initrd_max = 0x37ffffff; + + if (initrd_max >= ram_size-ACPI_DATA_SIZE) + initrd_max = ram_size-ACPI_DATA_SIZE-1; + + /* kernel command line */ + pstrcpy(cmdline_addr, 4096, kernel_cmdline); + + if (protocol >= 0x202) { + stl_p(header+0x228, cmdline_addr-phys_ram_base); + } else { + stw_p(header+0x20, 0xA33F); + stw_p(header+0x22, cmdline_addr-real_addr); + } + + /* loader type */ + /* High nybble = B reserved for Qemu; low nybble is revision number. + If this code is substantially changed, you may want to consider + incrementing the revision. */ + if (protocol >= 0x200) + header[0x210] = 0xB0; + + /* heap */ + if (protocol >= 0x201) { + header[0x211] |= 0x80; /* CAN_USE_HEAP */ + stw_p(header+0x224, cmdline_addr-real_addr-0x200); + } + + /* load initrd */ + if (initrd_filename) { + if (protocol < 0x200) { + fprintf(stderr, "qemu: linux kernel too old to load a ram disk\n"); + exit(1); + } + + fi = fopen(initrd_filename, "rb"); + if (!fi) { + fprintf(stderr, "qemu: could not load initial ram disk '%s'\n", + initrd_filename); + exit(1); + } + + initrd_size = get_file_size(fi); + initrd_addr = phys_ram_base + ((initrd_max-initrd_size) & ~4095); + + fprintf(stderr, "qemu: loading initrd (%#x bytes) at %#zx\n", + initrd_size, initrd_addr-phys_ram_base); + + if (fread(initrd_addr, 1, initrd_size, fi) != initrd_size) { + fprintf(stderr, "qemu: read error on initial ram disk '%s'\n", + initrd_filename); + exit(1); + } + fclose(fi); + + stl_p(header+0x218, initrd_addr-phys_ram_base); + stl_p(header+0x21c, initrd_size); + } + + /* store the finalized header and load the rest of the kernel */ + memcpy(real_addr, header, 1024); + + setup_size = header[0x1f1]; + if (setup_size == 0) + setup_size = 4; + + setup_size = (setup_size+1)*512; + kernel_size -= setup_size; /* Size of protected-mode code */ + + if (fread(real_addr+1024, 1, setup_size-1024, f) != setup_size-1024 || + fread(prot_addr, 1, kernel_size, f) != kernel_size) { + fprintf(stderr, "qemu: read error on kernel '%s'\n", + kernel_filename); + exit(1); + } + fclose(f); + + /* generate bootsector to set up the initial register state */ + real_seg = (real_addr-phys_ram_base) >> 4; + seg[0] = seg[2] = seg[3] = seg[4] = seg[4] = real_seg; + seg[1] = real_seg+0x20; /* CS */ + memset(gpr, 0, sizeof gpr); + gpr[4] = cmdline_addr-real_addr-16; /* SP (-16 is paranoia) */ + + generate_bootsect(gpr, seg, 0); +} + static void main_cpu_reset(void *opaque) { CPUState *env = opaque; @@ -453,9 +667,8 @@ static void pc_init1(int ram_size, int vga_ram_size, int boot_device, int pci_enabled) { char buf[1024]; - int ret, linux_boot, initrd_size, i; + int ret, linux_boot, i; ram_addr_t ram_addr, vga_ram_addr, bios_offset, vga_bios_offset; - ram_addr_t initrd_offset; int bios_size, isa_bios_size, vga_bios_size; PCIBus *pci_bus; int piix3_devfn = -1; @@ -570,81 +783,8 @@ static void pc_init1(int ram_size, int vga_ram_size, int boot_device, bochs_bios_init(); - if (linux_boot) { - uint8_t bootsect[512]; - uint8_t old_bootsect[512]; - - if (bs_table[0] == NULL) { - fprintf(stderr, "A disk image must be given for 'hda' when booting a Linux kernel\n"); - exit(1); - } - snprintf(buf, sizeof(buf), "%s/%s", bios_dir, LINUX_BOOT_FILENAME); - ret = load_image(buf, bootsect); - if (ret != sizeof(bootsect)) { - fprintf(stderr, "qemu: could not load linux boot sector '%s'\n", - buf); - exit(1); - } - - if (bdrv_read(bs_table[0], 0, old_bootsect, 1) >= 0) { - /* copy the MSDOS partition table */ - memcpy(bootsect + 0x1be, old_bootsect + 0x1be, 0x40); - } - - bdrv_set_boot_sector(bs_table[0], bootsect, sizeof(bootsect)); - - /* now we can load the kernel */ - ret = load_kernel(kernel_filename, - phys_ram_base + KERNEL_LOAD_ADDR, - phys_ram_base + KERNEL_PARAMS_ADDR); - if (ret < 0) { - fprintf(stderr, "qemu: could not load kernel '%s'\n", - kernel_filename); - exit(1); - } - - /* load initrd */ - initrd_size = 0; - initrd_offset = 0; - if (initrd_filename) { - initrd_size = get_image_size (initrd_filename); - if (initrd_size > 0) { - initrd_offset = (ram_size - initrd_size) & TARGET_PAGE_MASK; - /* Leave space for BIOS ACPI tables. */ - initrd_offset -= ACPI_DATA_SIZE; - /* Avoid the last 64k to avoid 2.2.x kernel bugs. */ - initrd_offset -= 0x10000; - if (initrd_offset > MAX_INITRD_LOAD_ADDR) - initrd_offset = MAX_INITRD_LOAD_ADDR; - - if (initrd_size > ram_size - || initrd_offset < KERNEL_LOAD_ADDR + ret) { - fprintf(stderr, - "qemu: memory too small for initial ram disk '%s'\n", - initrd_filename); - exit(1); - } - initrd_size = load_image(initrd_filename, - phys_ram_base + initrd_offset); - } - if (initrd_size < 0) { - fprintf(stderr, "qemu: could not load initial ram disk '%s'\n", - initrd_filename); - exit(1); - } - } - if (initrd_size > 0) { - stl_raw(phys_ram_base + KERNEL_PARAMS_ADDR + 0x218, initrd_offset); - stl_raw(phys_ram_base + KERNEL_PARAMS_ADDR + 0x21c, initrd_size); - } - pstrcpy(phys_ram_base + KERNEL_CMDLINE_ADDR, 4096, - kernel_cmdline); - stw_raw(phys_ram_base + KERNEL_PARAMS_ADDR + 0x20, 0xA33F); - stw_raw(phys_ram_base + KERNEL_PARAMS_ADDR + 0x22, - KERNEL_CMDLINE_ADDR - KERNEL_PARAMS_ADDR); - /* loader type */ - stw_raw(phys_ram_base + KERNEL_PARAMS_ADDR + 0x210, 0x01); - } + if (linux_boot) + load_linux(kernel_filename, initrd_filename, kernel_cmdline); cpu_irq = qemu_allocate_irqs(pic_irq_request, first_cpu, 1); i8259 = i8259_init(cpu_irq[0]); diff --git a/pc-bios/Makefile b/pc-bios/Makefile index 7ae0ff02a0..c817e851cf 100644 --- a/pc-bios/Makefile +++ b/pc-bios/Makefile @@ -6,16 +6,9 @@ include ../config-host.mak DEFINES= TARGETS= -ifeq ($(ARCH),i386) -TARGETS+=linux_boot.bin -endif all: $(TARGETS) -linux_boot.bin: linux_boot.o - ld --oformat binary -Ttext 0 -o $@ $< - chmod a-x $@ - %.o: %.S $(CC) $(DEFINES) -c -o $@ $< |