ref: aa0b6bedf4151dffec81e38b3c166aaac51c04c1
dir: /sys/src/boot/efi/x64.s/
MODE $64 TEXT start(SB), 1, $-4 /* spill arguments */ MOVQ CX, 8(SP) MOVQ DX, 16(SP) CALL reloc(SP) TEXT reloc(SB), 1, $-4 MOVQ 0(SP), SI SUBQ $reloc-IMAGEBASE(SB), SI MOVQ $IMAGEBASE, DI MOVQ $edata-IMAGEBASE(SB), CX CLD REP; MOVSB MOVQ 16(SP), BP MOVQ $efimain(SB), DI MOVQ DI, (SP) RET TEXT eficall(SB), 1, $-4 MOVQ SP, SI MOVQ SP, DI MOVL $(8*16), CX SUBQ CX, DI ANDQ $~15ULL, DI LEAQ 16(DI), SP CLD REP; MOVSB SUBQ $(8*16), SI MOVQ 0(SP), CX MOVQ 8(SP), DX MOVQ 16(SP), R8 MOVQ 24(SP), R9 CALL BP MOVQ SI, SP RET TEXT rebase(SB), 1, $-4 MOVQ BP, AX RET #include "mem.h" TEXT jump(SB), 1, $-4 CLI /* load zero length idt */ MOVL $_idtptr64p<>(SB), AX MOVL (AX), IDTR /* load temporary gdt */ MOVL $_gdtptr64p<>(SB), AX MOVL (AX), GDTR /* load CS with 32bit code segment */ PUSHQ $SELECTOR(3, SELGDT, 0) PUSHQ $_warp32<>(SB) RETFQ MODE $32 TEXT _warp32<>(SB), 1, $-4 /* load 32bit data segments */ MOVL $SELECTOR(2, SELGDT, 0), AX MOVW AX, DS MOVW AX, ES MOVW AX, FS MOVW AX, GS MOVW AX, SS /* turn off paging */ MOVL CR0, AX ANDL $0x7fffffff, AX /* ~(PG) */ MOVL AX, CR0 MOVL $0, AX MOVL AX, CR3 /* disable long mode */ MOVL $0xc0000080, CX /* Extended Feature Enable */ RDMSR ANDL $0xfffffeff, AX /* Long Mode Disable */ WRMSR /* diable pae */ MOVL CR4, AX ANDL $0xffffff5f, AX /* ~(PAE|PGE) */ MOVL AX, CR4 JMP *BP TEXT _gdt<>(SB), 1, $-4 /* null descriptor */ LONG $0 LONG $0 /* (KESEG) 64 bit long mode exec segment */ LONG $(0xFFFF) LONG $(SEGL|SEGG|SEGP|(0xF<<16)|SEGPL(0)|SEGEXEC|SEGR) /* 32 bit data segment descriptor for 4 gigabytes (PL 0) */ LONG $(0xFFFF) LONG $(SEGG|SEGB|(0xF<<16)|SEGP|SEGPL(0)|SEGDATA|SEGW) /* 32 bit exec segment descriptor for 4 gigabytes (PL 0) */ LONG $(0xFFFF) LONG $(SEGG|SEGD|(0xF<<16)|SEGP|SEGPL(0)|SEGEXEC|SEGR) TEXT _gdtptr64p<>(SB), 1, $-4 WORD $(4*8-1) QUAD $_gdt<>(SB) TEXT _idtptr64p<>(SB), 1, $-4 WORD $0 QUAD $0 GLOBL confaddr(SB), $8 DATA confaddr(SB)/8, $CONFADDR