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|
;; @file
; Assembly code of the implementation of X64 CPU architectural protocol
;
; Copyright (c) 2005 - 2015, 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.
;
;;
.code
EXTRN mErrorCodeFlag:DWORD ; Error code flags for exceptions
ExternalVectorTablePtr QWORD 0 ; point to the external interrupt vector table
InitializeExternalVectorTablePtr PROC PUBLIC
mov ExternalVectorTablePtr, rcx
ret
InitializeExternalVectorTablePtr ENDP
;
;
;
;------------------------------------------------------------------------------
; Generic IDT Vector Handlers for the Host. They are all the same so they
; will compress really well.
;
; By knowing the return address for Vector 00 you can can calculate the
; vector number by looking at the call CommonInterruptEntry return address.
; (return address - (AsmIdtVector00 + 5))/8 == IDT index
;
;------------------------------------------------------------------------------
ALIGN 8
PUBLIC AsmIdtVector00
AsmIdtVector00 LABEL BYTE
REPEAT 256
call CommonInterruptEntry
dw ( $ - AsmIdtVector00 - 5 ) / 8 ; vector number
nop
ENDM
;---------------------------------------;
; CommonInterruptEntry ;
;---------------------------------------;
; The follow algorithm is used for the common interrupt routine.
;
; +---------------------+ <-- 16-byte aligned ensured by processor
; + Old SS +
; +---------------------+
; + Old RSP +
; +---------------------+
; + RFlags +
; +---------------------+
; + CS +
; +---------------------+
; + RIP +
; +---------------------+
; + Error Code +
; +---------------------+
; + RCX / Vector Number +
; +---------------------+
; + RBP +
; +---------------------+ <-- RBP, 16-byte aligned
;
CommonInterruptEntry PROC PUBLIC
cli
;
; All interrupt handlers are invoked through interrupt gates, so
; IF flag automatically cleared at the entry point
;
;
; Calculate vector number
;
xchg rcx, [rsp] ; get the return address of call, actually, it is the address of vector number.
movzx ecx, word ptr [rcx]
cmp ecx, 32 ; Intel reserved vector for exceptions?
jae NoErrorCode
bt mErrorCodeFlag, ecx
jc @F
NoErrorCode:
;
; Push a dummy error code on the stack
; to maintain coherent stack map
;
push [rsp]
mov qword ptr [rsp + 8], 0
@@:
push rbp
mov rbp, rsp
;
; Since here the stack pointer is 16-byte aligned, so
; EFI_FX_SAVE_STATE_X64 of EFI_SYSTEM_CONTEXT_x64
; is 16-byte aligned
;
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
push r15
push r14
push r13
push r12
push r11
push r10
push r9
push r8
push rax
push qword ptr [rbp + 8] ; RCX
push rdx
push rbx
push qword ptr [rbp + 48] ; RSP
push qword ptr [rbp] ; RBP
push rsi
push rdi
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss; insure high 16 bits of each is zero
movzx rax, word ptr [rbp + 56]
push rax ; for ss
movzx rax, word ptr [rbp + 32]
push rax ; for cs
mov rax, ds
push rax
mov rax, es
push rax
mov rax, fs
push rax
mov rax, gs
push rax
mov [rbp + 8], rcx ; save vector number
;; UINT64 Rip;
push qword ptr [rbp + 24]
;; UINT64 Gdtr[2], Idtr[2];
sub rsp, 16
sidt fword ptr [rsp]
sub rsp, 16
sgdt fword ptr [rsp]
;; UINT64 Ldtr, Tr;
xor rax, rax
str ax
push rax
sldt ax
push rax
;; UINT64 RFlags;
push qword ptr [rbp + 40]
;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
mov rax, cr8
push rax
mov rax, cr4
or rax, 208h
mov cr4, rax
push rax
mov rax, cr3
push rax
mov rax, cr2
push rax
xor rax, rax
push rax
mov rax, cr0
push rax
;; UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
mov rax, dr7
push rax
;; clear Dr7 while executing debugger itself
xor rax, rax
mov dr7, rax
mov rax, dr6
push rax
;; insure all status bits in dr6 are clear...
xor rax, rax
mov dr6, rax
mov rax, dr3
push rax
mov rax, dr2
push rax
mov rax, dr1
push rax
mov rax, dr0
push rax
;; FX_SAVE_STATE_X64 FxSaveState;
sub rsp, 512
mov rdi, rsp
db 0fh, 0aeh, 00000111y ;fxsave [rdi]
;; UINT32 ExceptionData;
push qword ptr [rbp + 16]
;; call into exception handler
mov rcx, [rbp + 8]
mov rax, ExternalVectorTablePtr ; get the interrupt vectors base
mov rax, [rax + rcx * 8]
or rax, rax ; NULL?
je nonNullValue;
;; Prepare parameter and call
; mov rcx, [rbp + 8]
mov rdx, rsp
;
; Per X64 calling convention, allocate maximum parameter stack space
; and make sure RSP is 16-byte aligned
;
sub rsp, 4 * 8 + 8
call rax
add rsp, 4 * 8 + 8
nonNullValue:
cli
;; UINT64 ExceptionData;
add rsp, 8
;; FX_SAVE_STATE_X64 FxSaveState;
mov rsi, rsp
db 0fh, 0aeh, 00001110y ; fxrstor [rsi]
add rsp, 512
;; UINT64 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
pop rax
mov dr0, rax
pop rax
mov dr1, rax
pop rax
mov dr2, rax
pop rax
mov dr3, rax
;; skip restore of dr6. We cleared dr6 during the context save.
add rsp, 8
pop rax
mov dr7, rax
;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
pop rax
mov cr0, rax
add rsp, 8 ; not for Cr1
pop rax
mov cr2, rax
pop rax
mov cr3, rax
pop rax
mov cr4, rax
pop rax
mov cr8, rax
;; UINT64 RFlags;
pop qword ptr [rbp + 40]
;; UINT64 Ldtr, Tr;
;; UINT64 Gdtr[2], Idtr[2];
;; Best not let anyone mess with these particular registers...
add rsp, 48
;; UINT64 Rip;
pop qword ptr [rbp + 24]
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss;
pop rax
; mov gs, rax ; not for gs
pop rax
; mov fs, rax ; not for fs
; (X64 will not use fs and gs, so we do not restore it)
pop rax
mov es, rax
pop rax
mov ds, rax
pop qword ptr [rbp + 32] ; for cs
pop qword ptr [rbp + 56] ; for ss
;; UINT64 Rdi, Rsi, Rbp, Rsp, Rbx, Rdx, Rcx, Rax;
;; UINT64 R8, R9, R10, R11, R12, R13, R14, R15;
pop rdi
pop rsi
add rsp, 8 ; not for rbp
pop qword ptr [rbp + 48] ; for rsp
pop rbx
pop rdx
pop rcx
pop rax
pop r8
pop r9
pop r10
pop r11
pop r12
pop r13
pop r14
pop r15
mov rsp, rbp
pop rbp
add rsp, 16
iretq
CommonInterruptEntry ENDP
LongMode PROC PUBLIC
in_long_mode::
;
; Debug Stop
;
jmp in_long_mode
;
; We're in long mode, so marshall the arguments to call the
; passed in function pointers
; Recall
; [ebp][10h] = HobStart
; [ebp][18h] = Stack
; [ebp][20h] = PpisNeededByDxeIplEntryPoint <--- Call this first (for each call, pass HOB pointer)
; [ebp][28h] = DxeCoreEntryPoint <--- Call this second
;
mov rbx, [rbp+18h] ; Setup the stack
mov rsp, rbx ; On a new stack now
mov rcx, [rbp+10h] ; Pass Hob Start in RCX
mov rax, [rbp+20h] ; Get the function pointer for
; PpisNeededByDxeIplEntryPoint into EAX
call fword ptr [rax] ; Make the call into PpisNeededByDxeIplEntryPoint
mov ecx, [rbp+10h] ; Pass Hob Start in RCX
mov eax, [rbp+28h] ; Get the function pointer for
; DxeCoreEntryPoint into EAX
call fword ptr [rax] ; Make the call into Dxe Core
call CommonInterruptEntry
mov rdi, CommonInterruptEntry
lgdt fword ptr [rdi]
lidt fword ptr [rdi]
call near ptr [rax] ; Make the call into PpisNeededByDxeIplEntryPoint
call rax
;
; Should never get here.
;
no_long_mode:
jmp no_long_mode
;
; WE SHOULD NEVER GET HERE!!!!!!!!!!!!!
;
LongMode endp
MpMtrrSynchUpEntry PROC PUBLIC
;
; Enter no fill cache mode, CD=1(Bit30), NW=0 (Bit29)
;
mov rax, cr0
and rax, 0DFFFFFFFh
or rax, 040000000h
mov cr0, rax
;
; Flush cache
;
wbinvd
;
; Clear PGE flag Bit 7
;
mov rax, cr4
mov rdx, rax
and rax, 0FFFFFF7Fh
mov cr4, rax
;
; Flush all TLBs
;
mov rax, cr3
mov cr3, rax
mov rax, rdx
ret
MpMtrrSynchUpEntry ENDP
MpMtrrSynchUpExit PROC PUBLIC
;
; Flush all TLBs the second time
;
mov rax, cr3
mov cr3, rax
;
; Enable Normal Mode caching CD=NW=0, CD(Bit30), NW(Bit29)
;
mov rax, cr0
and rax, 09FFFFFFFh
mov cr0, rax
;
; Set PGE Flag in CR4 if set
;
mov cr4, rcx
ret
MpMtrrSynchUpExit ENDP
CpuInitFloatPointUnit PROC PUBLIC
; bugbug
; finit
ret
CpuInitFloatPointUnit ENDP
CpuDisableInterrupt PROC PUBLIC
cli
ret
CpuDisableInterrupt ENDP
CpuEnableInterrupt PROC PUBLIC
sti
ret
CpuEnableInterrupt ENDP
GetCoreNumber PROC PUBLIC
push rbx
mov eax, 4
mov ecx, 0
cpuid
shr eax, 26
and eax, 3fh
inc al
pop rbx
ret
GetCoreNumber ENDP
END
|