Convert linux bootrom to external rom and fw_cfg
We already have a working multiboot implementation that uses fw_cfg to get
its kernel module etc. data in int19 runtime now.
So what's missing is a working linux boot option rom. While at it I figured it
would be a good idea to take the opcode generator out of pc.c and instead use
a proper option rom, like we do with multiboot.
So here it is - an fw_cfg using option rom for -kernel with linux!
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/pc.c b/hw/pc.c
index 55bd1a4..7c791c4 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -487,85 +487,6 @@
return fw_cfg;
}
-/* Generate an initial boot sector which sets state and jump to
- a specified vector */
-static void generate_bootsect(uint32_t gpr[8], uint16_t segs[6], uint16_t ip)
-{
- uint8_t rom[512], *p, *reloc;
- uint8_t sum;
- int i;
-
- memset(rom, 0, sizeof(rom));
-
- p = rom;
- /* Make sure we have an option rom signature */
- *p++ = 0x55;
- *p++ = 0xaa;
-
- /* ROM size in sectors*/
- *p++ = 1;
-
- /* Hook int19 */
-
- *p++ = 0x50; /* push ax */
- *p++ = 0x1e; /* push ds */
- *p++ = 0x31; *p++ = 0xc0; /* xor ax, ax */
- *p++ = 0x8e; *p++ = 0xd8; /* mov ax, ds */
-
- *p++ = 0xc7; *p++ = 0x06; /* movvw _start,0x64 */
- *p++ = 0x64; *p++ = 0x00;
- reloc = p;
- *p++ = 0x00; *p++ = 0x00;
-
- *p++ = 0x8c; *p++ = 0x0e; /* mov cs,0x66 */
- *p++ = 0x66; *p++ = 0x00;
-
- *p++ = 0x1f; /* pop ds */
- *p++ = 0x58; /* pop ax */
- *p++ = 0xcb; /* lret */
-
- /* Actual code */
- *reloc = (p - rom);
-
- *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;
-
- /* sign rom */
- sum = 0;
- for (i = 0; i < (sizeof(rom) - 1); i++)
- sum += rom[i];
- rom[sizeof(rom) - 1] = -sum;
-
- rom_add_blob("linux-bootsect", rom, sizeof(rom),
- PC_ROM_MIN_OPTION, PC_ROM_MAX, PC_ROM_ALIGN);
-}
-
static long get_file_size(FILE *f)
{
long where, size;
@@ -812,12 +733,9 @@
target_phys_addr_t max_ram_size)
{
uint16_t protocol;
- uint32_t gpr[8];
- uint16_t seg[6];
- uint16_t real_seg;
int setup_size, kernel_size, initrd_size = 0, cmdline_size;
uint32_t initrd_max;
- uint8_t header[8192], *setup, *kernel;
+ uint8_t header[8192], *setup, *kernel, *initrd_data;
target_phys_addr_t real_addr, prot_addr, cmdline_addr, initrd_addr = 0;
FILE *f;
char *vmode;
@@ -886,9 +804,11 @@
if (initrd_max >= max_ram_size-ACPI_DATA_SIZE)
initrd_max = max_ram_size-ACPI_DATA_SIZE-1;
- /* kernel command line */
- rom_add_blob_fixed("cmdline", kernel_cmdline,
- strlen(kernel_cmdline)+1, cmdline_addr);
+ fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_ADDR, cmdline_addr);
+ fw_cfg_add_i32(fw_cfg, FW_CFG_CMDLINE_SIZE, strlen(kernel_cmdline)+1);
+ fw_cfg_add_bytes(fw_cfg, FW_CFG_CMDLINE_DATA,
+ (uint8_t*)strdup(kernel_cmdline),
+ strlen(kernel_cmdline)+1);
if (protocol >= 0x202) {
stl_p(header+0x228, cmdline_addr);
@@ -937,7 +857,13 @@
initrd_size = get_image_size(initrd_filename);
initrd_addr = (initrd_max-initrd_size) & ~4095;
- rom_add_file_fixed(initrd_filename, initrd_addr);
+
+ initrd_data = qemu_malloc(initrd_size);
+ load_image(initrd_filename, initrd_data);
+
+ fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, initrd_addr);
+ fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, initrd_size);
+ fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, initrd_data, initrd_size);
stl_p(header+0x218, initrd_addr);
stl_p(header+0x21c, initrd_size);
@@ -957,21 +883,17 @@
fread(kernel, 1, kernel_size, f);
fclose(f);
memcpy(setup, header, MIN(sizeof(header), setup_size));
- rom_add_blob_fixed("linux-setup", setup,
- setup_size, real_addr);
- rom_add_blob_fixed(kernel_filename, kernel,
- kernel_size, prot_addr);
- qemu_free(setup);
- qemu_free(kernel);
- /* generate bootsector to set up the initial register state */
- real_seg = real_addr >> 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) */
+ fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, prot_addr);
+ fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, kernel_size);
+ fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA, kernel, kernel_size);
- generate_bootsect(gpr, seg, 0);
+ fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_ADDR, real_addr);
+ fw_cfg_add_i32(fw_cfg, FW_CFG_SETUP_SIZE, setup_size);
+ fw_cfg_add_bytes(fw_cfg, FW_CFG_SETUP_DATA, setup, setup_size);
+
+ option_rom[nb_option_roms] = "linuxboot.bin";
+ nb_option_roms++;
}
static const int ide_iobase[2] = { 0x1f0, 0x170 };
