;------------------------------------------------------------------------------ ;* ;* Copyright (c) 2006, Intel Corporation. All rights reserved.<BR> ;* This program and the accompanying materials ;* are licensed and made available under the terms and conditions of the BSD License ;* which accompanies this distribution. The full text of the license may be found at ;* http://opensource.org/licenses/bsd-license.php ;* ;* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, ;* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. ;* ;* efi64.asm ;* ;* Abstract: ;* ;------------------------------------------------------------------------------ ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Now in 64-bit long mode. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; .486 .model flat .stack .code org 21000h DEFAULT_HANDLER_SIZE EQU INT1 - INT0 JmpCommonIdtEntry macro ; jmp commonIdtEntry - this must be hand coded to keep the assembler from ; using a 8 bit reletive jump when the entries are ; within 255 bytes of the common entry. This must ; be done to maintain the consistency of the size ; of entry points... db 0e9h ; jmp 16 bit reletive dd commonIdtEntry - $ - 4 ; offset to jump to endm Start: mov esp,0001fffe8h ; make final stack aligned ; set OSFXSR and OSXMMEXCPT because some code will use XMM register db 0fh db 20h db 0e0h ; mov rax, cr4 bts eax, 9 bts eax, 0ah db 0fh db 22h db 0e0h ; mov cr4, rax call ClearScreen ; Populate IDT with meaningful offsets for exception handlers... mov eax, offset Idtr sidt fword ptr [eax] ; get fword address of IDT mov eax, offset Halt mov ebx, eax ; use bx to copy 15..0 to descriptors shr eax, 16 ; use ax to copy 31..16 to descriptors ; 63..32 of descriptors is 0 mov ecx, 78h ; 78h IDT entries to initialize with unique entry points (exceptions) mov esi, [offset Idtr + 2] mov edi, [esi] @@: ; loop through all IDT entries exception handlers and initialize to default handler mov word ptr [edi], bx ; write bits 15..0 of offset mov word ptr [edi+2], 38h ; SYS_CODE64_SEL from GDT mov word ptr [edi+4], 0e00h OR 8000h ; type = 386 interrupt gate, present mov word ptr [edi+6], ax ; write bits 31..16 of offset mov dword ptr [edi+8], 0 ; write bits 63..32 of offset add edi, 16 ; move up to next descriptor add bx, DEFAULT_HANDLER_SIZE ; move to next entry point loop @b ; loop back through again until all descriptors are initialized ;; at this point edi contains the offset of the descriptor for INT 20 ;; and bx contains the low 16 bits of the offset of the default handler ;; so initialize all the rest of the descriptors with these two values... ; mov ecx, 101 ; there are 100 descriptors left (INT 20 (14h) - INT 119 (77h) ;@@: ; loop through all IDT entries exception handlers and initialize to default handler ; mov word ptr [edi], bx ; write bits 15..0 of offset ; mov word ptr [edi+2], 38h ; SYS_CODE64_SEL from GDT ; mov word ptr [edi+4], 0e00h OR 8000h ; type = 386 interrupt gate, present ; mov word ptr [edi+6], ax ; write bits 31..16 of offset ; mov dword ptr [edi+8], 0 ; write bits 63..32 of offset ; add edi, 16 ; move up to next descriptor ; loop @b ; loop back through again until all descriptors are initialized ;; DUMP location of IDT and several of the descriptors ; mov ecx, 8 ; mov eax, [offset Idtr + 2] ; mov eax, [eax] ; mov edi, 0b8000h ; call PrintQword ; mov esi, eax ; mov edi, 0b80a0h ; jmp OuterLoop ;; ;; just for fun, let's do a software interrupt to see if we correctly land in the exception handler... ; mov eax, 011111111h ; mov ebx, 022222222h ; mov ecx, 033333333h ; mov edx, 044444444h ; mov ebp, 055555555h ; mov esi, 066666666h ; mov edi, 077777777h ; push 011111111h ; push 022222222h ; push 033333333h ; int 119 mov esi,022000h ; esi = 22000 mov eax,[esi+014h] ; eax = [22014] add esi,eax ; esi = 22000 + [22014] = Base of EFILDR.C mov ebp,[esi+03ch] ; ebp = [22000 + [22014] + 3c] = NT Image Header for EFILDR.C add ebp,esi mov edi,[ebp+030h] ; edi = [[22000 + [22014] + 3c] + 2c] = ImageBase (63..32 is zero, ignore) mov eax,[ebp+028h] ; eax = [[22000 + [22014] + 3c] + 24] = EntryPoint add eax,edi ; eax = ImageBase + EntryPoint mov ebx, offset EfiLdrOffset mov dword ptr [ebx],eax ; Modify far jump instruction for correct entry point mov bx,word ptr[ebp+6] ; bx = Number of sections xor eax,eax mov ax,word ptr[ebp+014h] ; ax = Optional Header Size add ebp,eax add ebp,018h ; ebp = Start of 1st Section SectionLoop: push esi ; Save Base of EFILDR.C push edi ; Save ImageBase add esi,[ebp+014h] ; esi = Base of EFILDR.C + PointerToRawData add edi,[ebp+00ch] ; edi = ImageBase + VirtualAddress mov ecx,[ebp+010h] ; ecs = SizeOfRawData cld shr ecx,2 rep movsd pop edi ; Restore ImageBase pop esi ; Restore Base of EFILDR.C add bp,028h ; ebp = ebp + 028h = Pointer to next section record db 66h db 0ffh db 0cbh ; dec bx cmp bx,0 jne SectionLoop mov edx, offset Idtr movzx eax, word ptr [edx] ; get size of IDT db 0ffh db 0c0h ; inc eax add eax, dword ptr [edx + 2] ; add to base of IDT to get location of memory map... xor ecx, ecx mov ecx, eax ; put argument to RCX db 48h db 0c7h db 0c0h EfiLdrOffset: dd 000401000h ; Offset of EFILDR ; mov rax, 401000h db 50h ; push rax ; ret db 0c3h ; db "**** DEFAULT IDT ENTRY ***",0 align 02h Halt: INT0: push 0h ; push error code place holder on the stack push 0h JmpCommonIdtEntry ; db 0e9h ; jmp 16 bit reletive ; dd commonIdtEntry - $ - 4 ; offset to jump to INT1: push 0h ; push error code place holder on the stack push 1h JmpCommonIdtEntry INT2: push 0h ; push error code place holder on the stack push 2h JmpCommonIdtEntry INT3: push 0h ; push error code place holder on the stack push 3h JmpCommonIdtEntry INT4: push 0h ; push error code place holder on the stack push 4h JmpCommonIdtEntry INT5: push 0h ; push error code place holder on the stack push 5h JmpCommonIdtEntry INT6: push 0h ; push error code place holder on the stack push 6h JmpCommonIdtEntry INT7: push 0h ; push error code place holder on the stack push 7h JmpCommonIdtEntry INT8: ; Double fault causes an error code to be pushed so no phony push necessary nop nop push 8h JmpCommonIdtEntry INT9: push 0h ; push error code place holder on the stack push 9h JmpCommonIdtEntry INT10: ; Invalid TSS causes an error code to be pushed so no phony push necessary nop nop push 10 JmpCommonIdtEntry INT11: ; Segment Not Present causes an error code to be pushed so no phony push necessary nop nop push 11 JmpCommonIdtEntry INT12: ; Stack fault causes an error code to be pushed so no phony push necessary nop nop push 12 JmpCommonIdtEntry INT13: ; GP fault causes an error code to be pushed so no phony push necessary nop nop push 13 JmpCommonIdtEntry INT14: ; Page fault causes an error code to be pushed so no phony push necessary nop nop push 14 JmpCommonIdtEntry INT15: push 0h ; push error code place holder on the stack push 15 JmpCommonIdtEntry INT16: push 0h ; push error code place holder on the stack push 16 JmpCommonIdtEntry INT17: ; Alignment check causes an error code to be pushed so no phony push necessary nop nop push 17 JmpCommonIdtEntry INT18: push 0h ; push error code place holder on the stack push 18 JmpCommonIdtEntry INT19: push 0h ; push error code place holder on the stack push 19 JmpCommonIdtEntry INTUnknown: REPEAT (78h - 20) push 0h ; push error code place holder on the stack ; push xxh ; push vector number db 06ah db ( $ - INTUnknown - 3 ) / 9 + 20 ; vector number JmpCommonIdtEntry ENDM commonIdtEntry: push eax push ecx push edx push ebx push esp push ebp push esi push edi db 41h db 50h ; push r8 db 41h db 51h ; push r9 db 41h db 52h ; push r10 db 41h db 53h ; push r11 db 41h db 54h ; push r12 db 41h db 55h ; push r13 db 41h db 56h ; push r14 db 41h db 57h ; push r15 db 48h mov ebp, esp ; mov rbp, rsp ;; ;; At this point the stack looks like this: ;; ;; Calling SS ;; Calling RSP ;; rflags ;; Calling CS ;; Calling RIP ;; Error code or 0 ;; Int num or 0ffh for unknown int num ;; rax ;; rcx ;; rdx ;; rbx ;; rsp ;; rbp ;; rsi ;; rdi ;; r8 ;; r9 ;; r10 ;; r11 ;; r12 ;; r13 ;; r14 ;; r15 <------- RSP, RBP ;; call ClearScreen mov esi, offset String1 call PrintString db 48h mov eax, [ebp + 16*8] ;; move Int number into RAX db 48h cmp eax, 18 ja PrintDefaultString PrintExceptionString: shl eax, 3 ;; multiply by 8 to get offset from StringTable to actual string address add eax, offset StringTable mov esi, [eax] jmp PrintTheString PrintDefaultString: mov esi, offset IntUnknownString ; patch Int number mov edx, eax call A2C mov [esi + 1], al mov eax, edx shr eax, 4 call A2C mov [esi], al PrintTheString: call PrintString mov esi, offset String2 call PrintString db 48h mov eax, [ebp+19*8] ; CS call PrintQword mov al, ':' mov byte ptr [edi], al add edi, 2 db 48h mov eax, [ebp+18*8] ; RIP call PrintQword mov esi, offset String3 call PrintString mov edi, 0b8140h mov esi, offset StringRax ; rax call PrintString db 48h mov eax, [ebp+15*8] call PrintQword mov esi, offset StringRcx ; rcx call PrintString db 48h mov eax, [ebp+14*8] call PrintQword mov esi, offset StringRdx ; rdx call PrintString db 48h mov eax, [ebp+13*8] call PrintQword mov edi, 0b81e0h mov esi, offset StringRbx ; rbx call PrintString db 48h mov eax, [ebp+12*8] call PrintQword mov esi, offset StringRsp ; rsp call PrintString db 48h mov eax, [ebp+21*8] call PrintQword mov esi, offset StringRbp ; rbp call PrintString db 48h mov eax, [ebp+10*8] call PrintQword mov edi, 0b8280h mov esi, offset StringRsi ; rsi call PrintString db 48h mov eax, [ebp+9*8] call PrintQword mov esi, offset StringRdi ; rdi call PrintString db 48h mov eax, [ebp+8*8] call PrintQword mov esi, offset StringEcode ; error code call PrintString db 48h mov eax, [ebp+17*8] call PrintQword mov edi, 0b8320h mov esi, offset StringR8 ; r8 call PrintString db 48h mov eax, [ebp+7*8] call PrintQword mov esi, offset StringR9 ; r9 call PrintString db 48h mov eax, [ebp+6*8] call PrintQword mov esi, offset StringR10 ; r10 call PrintString db 48h mov eax, [ebp+5*8] call PrintQword mov edi, 0b83c0h mov esi, offset StringR11 ; r11 call PrintString db 48h mov eax, [ebp+4*8] call PrintQword mov esi, offset StringR12 ; r12 call PrintString db 48h mov eax, [ebp+3*8] call PrintQword mov esi, offset StringR13 ; r13 call PrintString db 48h mov eax, [ebp+2*8] call PrintQword mov edi, 0b8460h mov esi, offset StringR14 ; r14 call PrintString db 48h mov eax, [ebp+1*8] call PrintQword mov esi, offset StringR15 ; r15 call PrintString db 48h mov eax, [ebp+0*8] call PrintQword mov esi, offset StringSs ; ss call PrintString db 48h mov eax, [ebp+22*8] call PrintQword mov edi, 0b8500h mov esi, offset StringRflags ; rflags call PrintString db 48h mov eax, [ebp+20*8] call PrintQword mov edi, 0b8640h mov esi, ebp add esi, 23*8 mov ecx, 4 OuterLoop: push ecx mov ecx, 4 db 48h mov edx, edi InnerLoop: db 48h mov eax, [esi] call PrintQword add esi, 8 mov al, ' ' mov [edi], al add edi, 2 loop InnerLoop pop ecx add edx, 0a0h mov edi, edx loop OuterLoop mov edi, 0b8960h db 48h mov eax, [ebp+18*8] ; RIP sub eax, 8 * 8 db 48h mov esi, eax ; esi = rip - 8 QWORD linear (total 16 QWORD) mov ecx, 4 OuterLoop1: push ecx mov ecx, 4 mov edx, edi InnerLoop1: db 48h mov eax, [esi] call PrintQword add esi, 8 mov al, ' ' mov [edi], al add edi, 2 loop InnerLoop1 pop ecx add edx, 0a0h mov edi, edx loop OuterLoop1 ;wbinvd @@: jmp @b ; ; return ; mov esp, ebp ; mov rsp, rbp db 41h db 5fh ; pop r15 db 41h db 5eh ; pop r14 db 41h db 5dh ; pop r13 db 41h db 5ch ; pop r12 db 41h db 5bh ; pop r11 db 41h db 5ah ; pop r10 db 41h db 59h ; pop r9 db 41h db 58h ; pop r8 pop edi pop esi pop ebp pop eax ; esp pop ebx pop edx pop ecx pop eax db 48h db 83h db 0c4h db 10h ; add esp, 16 ; error code and INT number db 48h db 0cfh ; iretq PrintString: push eax @@: mov al, byte ptr [esi] cmp al, 0 je @f mov byte ptr [edi], al db 0ffh db 0c6h ; inc esi add edi, 2 jmp @b @@: pop eax ret ;; RAX contains qword to print ;; RDI contains memory location (screen location) to print it to PrintQword: push ecx push ebx push eax db 48h db 0c7h db 0c1h dd 16 ; mov rcx, 16 looptop: db 48h rol eax, 4 mov bl, al and bl, 0fh add bl, '0' cmp bl, '9' jle @f add bl, 7 @@: mov byte ptr [edi], bl add edi, 2 loop looptop ;wbinvd pop eax pop ebx pop ecx ret ClearScreen: push eax push ecx mov al, ' ' mov ah, 0ch mov edi, 0b8000h mov ecx, 80 * 24 @@: mov word ptr [edi], ax add edi, 2 loop @b mov edi, 0b8000h pop ecx pop eax ret A2C: and al, 0fh add al, '0' cmp al, '9' jle @f add al, 7 @@: ret String1 db "*** INT ",0 Int0String db "00h Divide by 0 -",0 Int1String db "01h Debug exception -",0 Int2String db "02h NMI -",0 Int3String db "03h Breakpoint -",0 Int4String db "04h Overflow -",0 Int5String db "05h Bound -",0 Int6String db "06h Invalid opcode -",0 Int7String db "07h Device not available -",0 Int8String db "08h Double fault -",0 Int9String db "09h Coprocessor seg overrun (reserved) -",0 Int10String db "0Ah Invalid TSS -",0 Int11String db "0Bh Segment not present -",0 Int12String db "0Ch Stack fault -",0 Int13String db "0Dh General protection fault -",0 Int14String db "0Eh Page fault -",0 Int15String db "0Fh (Intel reserved) -",0 Int16String db "10h Floating point error -",0 Int17String db "11h Alignment check -",0 Int18String db "12h Machine check -",0 Int19String db "13h SIMD Floating-Point Exception -",0 IntUnknownString db "??h Unknown interrupt -",0 StringTable dq offset Int0String, offset Int1String, offset Int2String, offset Int3String, offset Int4String, offset Int5String, offset Int6String, offset Int7String, offset Int8String, offset Int9String, offset Int10String, offset Int11String, offset Int12String, offset Int13String, offset Int14String, offset Int15String, offset Int16String, offset Int17String, offset Int18String, offset Int19String String2 db " HALT!! *** (",0 String3 db ")",0 StringRax db "RAX=",0 StringRcx db " RCX=",0 StringRdx db " RDX=",0 StringRbx db "RBX=",0 StringRsp db " RSP=",0 StringRbp db " RBP=",0 StringRsi db "RSI=",0 StringRdi db " RDI=",0 StringEcode db " ECODE=",0 StringR8 db "R8 =",0 StringR9 db " R9 =",0 StringR10 db " R10=",0 StringR11 db "R11=",0 StringR12 db " R12=",0 StringR13 db " R13=",0 StringR14 db "R14=",0 StringR15 db " R15=",0 StringSs db " SS =",0 StringRflags db "RFLAGS=",0 Idtr df 0 df 0 org 21ffeh BlockSignature: dw 0aa55h end