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|
;------------------------------------------------------------------------------ ;
; Copyright (c) 2009 - 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.
;
; Module Name:
;
; SmiException.asm
;
; Abstract:
;
; Exception handlers used in SM mode
;
;-------------------------------------------------------------------------------
EXTERNDEF SmiPFHandler:PROC
EXTERNDEF gSmiMtrrs:QWORD
EXTERNDEF gcSmiIdtr:FWORD
EXTERNDEF gcSmiGdtr:FWORD
EXTERNDEF gcPsd:BYTE
.const
NullSeg DQ 0 ; reserved by architecture
CodeSeg32 LABEL QWORD
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 9bh
DB 0cfh ; LimitHigh
DB 0 ; BaseHigh
ProtModeCodeSeg32 LABEL QWORD
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 9bh
DB 0cfh ; LimitHigh
DB 0 ; BaseHigh
ProtModeSsSeg32 LABEL QWORD
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 93h
DB 0cfh ; LimitHigh
DB 0 ; BaseHigh
DataSeg32 LABEL QWORD
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 93h
DB 0cfh ; LimitHigh
DB 0 ; BaseHigh
CodeSeg16 LABEL QWORD
DW -1
DW 0
DB 0
DB 9bh
DB 8fh
DB 0
DataSeg16 LABEL QWORD
DW -1
DW 0
DB 0
DB 93h
DB 8fh
DB 0
CodeSeg64 LABEL QWORD
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 9bh
DB 0afh ; LimitHigh
DB 0 ; BaseHigh
; TSS Segment for X64 specially
TssSeg LABEL QWORD
DW TSS_DESC_SIZE - 1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 89h
DB 00h ; LimitHigh
DB 0 ; BaseHigh
DD 0 ; BaseUpper
DD 0 ; Reserved
GDT_SIZE = $ - offset NullSeg
; Create TSS Descriptor just after GDT
TssDescriptor LABEL BYTE
DD 0 ; Reserved
DQ 0 ; RSP0
DQ 0 ; RSP1
DQ 0 ; RSP2
DD 0 ; Reserved
DD 0 ; Reserved
DQ 0 ; IST1
DQ 0 ; IST2
DQ 0 ; IST3
DQ 0 ; IST4
DQ 0 ; IST5
DQ 0 ; IST6
DQ 0 ; IST7
DD 0 ; Reserved
DD 0 ; Reserved
DW 0 ; Reserved
DW 0 ; I/O Map Base Address
TSS_DESC_SIZE = $ - offset TssDescriptor
;
; This structure serves as a template for all processors.
;
gcPsd LABEL BYTE
DB 'PSDSIG '
DW PSD_SIZE
DW 2
DW 1 SHL 2
DW CODE_SEL
DW DATA_SEL
DW DATA_SEL
DW DATA_SEL
DW 0
DQ 0
DQ 0
DQ 0 ; fixed in InitializeMpServiceData()
DQ offset NullSeg
DD GDT_SIZE
DD 0
DB 24 dup (0)
DQ offset gSmiMtrrs
PSD_SIZE = $ - offset gcPsd
;
; CODE & DATA segments for SMM runtime
;
CODE_SEL = offset CodeSeg64 - offset NullSeg
DATA_SEL = offset DataSeg32 - offset NullSeg
CODE32_SEL = offset CodeSeg32 - offset NullSeg
gcSmiGdtr LABEL FWORD
DW GDT_SIZE - 1
DQ offset NullSeg
gcSmiIdtr LABEL FWORD
DW IDT_SIZE - 1
DQ offset _SmiIDT
.data
;
; Here is the IDT. There are 32 (not 255) entries in it since only processor
; generated exceptions will be handled.
;
_SmiIDT:
REPEAT 32
DW 0 ; Offset 0:15
DW CODE_SEL ; Segment selector
DB 0 ; Unused
DB 8eh ; Interrupt Gate, Present
DW 0 ; Offset 16:31
DQ 0 ; Offset 32:63
ENDM
_SmiIDTEnd:
IDT_SIZE = (offset _SmiIDTEnd - offset _SmiIDT)
.code
;------------------------------------------------------------------------------
; _SmiExceptionEntryPoints is the collection of exception entry points followed
; by a common exception handler.
;
; Stack frame would be as follows as specified in IA32 manuals:
;
; +---------------------+ <-- 16-byte aligned ensured by processor
; + Old SS +
; +---------------------+
; + Old RSP +
; +---------------------+
; + RFlags +
; +---------------------+
; + CS +
; +---------------------+
; + RIP +
; +---------------------+
; + Error Code +
; +---------------------+
; + Vector Number +
; +---------------------+
; + RBP +
; +---------------------+ <-- RBP, 16-byte aligned
;
; RSP set to odd multiple of 8 at @CommonEntryPoint means ErrCode PRESENT
;------------------------------------------------------------------------------
PageFaultIdtHandlerSmmProfile PROC
push 0eh ; Page Fault
test spl, 8 ; odd multiple of 8 => ErrCode present
jnz @F
push [rsp] ; duplicate INT# if no ErrCode
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 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
;; 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
mov rax, dr6
push 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]
; UEFI calling convention for x64 requires that Direction flag in EFLAGs is clear
cld
;; UINT32 ExceptionData;
push qword ptr [rbp + 16]
;; call into exception handler
mov rcx, [rbp + 8]
mov rax, SmiPFHandler
;; Prepare parameter and call
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
jmp @F
@@:
;; 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;
;; Skip restoration of DRx registers to support debuggers
;; that set breakpoints in interrupt/exception context
add rsp, 8 * 6
;; 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
; Enable TF bit after page fault handler runs
bts dword ptr [rsp + 40], 8 ;RFLAGS
pop rbp
add rsp, 16 ; skip INT# & ErrCode
iretq
PageFaultIdtHandlerSmmProfile ENDP
InitializeIDTSmmStackGuard PROC
;
; If SMM Stack Guard feature is enabled, set the IST field of
; the interrupt gate for Page Fault Exception to be 1
;
lea rax, _SmiIDT + 14 * 16
mov byte ptr [rax + 4], 1
ret
InitializeIDTSmmStackGuard ENDP
END
|
