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#include "bios.h"
#include "ioport.h"
#include "fw_cfg.h"
static void *_fw_cfg_read_blob(int faddr, int fsize, int fdata)
{
void *addr;
int length;
fw_cfg_select(faddr);
addr = (void *)fw_cfg_readl_le();
fw_cfg_select(fsize);
length = fw_cfg_readl_le();
fw_cfg_select(fdata);
fw_cfg_read(addr, length);
return addr;
}
/* BX = address of data block
* DX = cmdline_addr-setup_addr-16
*/
asm("pm16_boot_linux:"
".code16;"
"mov $0, %eax; mov %eax, %cr0;"
"ljmpl $0xf000, $(1f - 0xf0000); 1:"
"mov %bx, %ds; mov %bx, %es;"
"mov %bx, %fs; mov %bx, %gs; mov %bx, %ss;"
"mov %dx, %sp;"
"add $0x20, %bx; pushw %bx;" // push CS
"xor %eax, %eax; pushw %ax;" // push IP
"xor %ebx, %ebx;"
"xor %ecx, %ecx;"
"xor %edx, %edx;"
"xor %edi, %edi;"
"xor %ebp, %ebp;"
"lret;"
".code32");
void boot_linux(void)
{
void *setup_addr, *cmdline_addr;
#define fw_cfg_read_blob(f) \
_fw_cfg_read_blob(f##_ADDR, f##_SIZE, f##_DATA)
setup_addr = fw_cfg_read_blob(FW_CFG_SETUP);
cmdline_addr = fw_cfg_read_blob(FW_CFG_CMDLINE);
fw_cfg_read_blob(FW_CFG_INITRD);
fw_cfg_read_blob(FW_CFG_KERNEL);
asm volatile(
"ljmp $0x18, $pm16_boot_linux - 0xf0000"
: :
"b" (((uintptr_t) setup_addr) >> 4),
"d" (cmdline_addr - setup_addr - 16));
panic();
}
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