64 lines
1.3 KiB
C
64 lines
1.3 KiB
C
#include <sys/gdt.h>
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__attribute__((noreturn)) void linux_spinup(void *entry, void *boot_params) {
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struct gdt_desc linux_gdt_descs[] = {
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{0},
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{0},
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{
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.limit = 0xffff,
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.base_low = 0x0000,
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.base_mid = 0x00,
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.access = 0b10011010,
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.granularity = 0b11001111,
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.base_hi = 0x00
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},
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{
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.limit = 0xffff,
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.base_low = 0x0000,
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.base_mid = 0x00,
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.access = 0b10010010,
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.granularity = 0b11001111,
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.base_hi = 0x00
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}
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};
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struct gdtr linux_gdt = {
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sizeof(linux_gdt_descs) - 1,
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(uintptr_t)linux_gdt_descs,
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#if defined (bios)
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0
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#endif
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};
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asm volatile (
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"lgdt %0\n\t"
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"push 0x10\n\t"
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"call 1f\n\t"
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"1:\n\t"
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"add dword ptr [esp], 5\n\t"
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"retf\n\t"
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"mov eax, 0x18\n\t"
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"mov ds, eax\n\t"
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"mov es, eax\n\t"
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"mov fs, eax\n\t"
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"mov gs, eax\n\t"
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"mov ss, eax\n\t"
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"xor ebp, ebp\n\t"
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"xor edi, edi\n\t"
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"xor ebx, ebx\n\t"
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"jmp ecx\n\t"
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:
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: "m"(linux_gdt), "c"(entry), "S"(boot_params)
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: "memory"
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);
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__builtin_unreachable();
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}
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