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;------------------------------------------------------------------------------ ;
; Copyright (c) 2016, 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.nasm
;
; Abstract:
;
; Exception handlers used in SM mode
;
;-------------------------------------------------------------------------------
extern ASM_PFX(SmiPFHandler)
global ASM_PFX(gcSmiIdtr)
global ASM_PFX(gcSmiGdtr)
global ASM_PFX(gcPsd)
SECTION .data
NullSeg: DQ 0 ; reserved by architecture
CodeSeg32:
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 0x9b
DB 0xcf ; LimitHigh
DB 0 ; BaseHigh
ProtModeCodeSeg32:
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 0x9b
DB 0xcf ; LimitHigh
DB 0 ; BaseHigh
ProtModeSsSeg32:
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 0x93
DB 0xcf ; LimitHigh
DB 0 ; BaseHigh
DataSeg32:
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 0x93
DB 0xcf ; LimitHigh
DB 0 ; BaseHigh
CodeSeg16:
DW -1
DW 0
DB 0
DB 0x9b
DB 0x8f
DB 0
DataSeg16:
DW -1
DW 0
DB 0
DB 0x93
DB 0x8f
DB 0
CodeSeg64:
DW -1 ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 0x9b
DB 0xaf ; LimitHigh
DB 0 ; BaseHigh
; TSS Segment for X64 specially
TssSeg:
DW TSS_DESC_SIZE ; LimitLow
DW 0 ; BaseLow
DB 0 ; BaseMid
DB 0x89
DB 0x80 ; LimitHigh
DB 0 ; BaseHigh
DD 0 ; BaseUpper
DD 0 ; Reserved
GDT_SIZE equ $ - NullSeg
; Create TSS Descriptor just after GDT
TssDescriptor:
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 equ $ - TssDescriptor
;
; This structure serves as a template for all processors.
;
ASM_PFX(gcPsd):
DB 'PSDSIG '
DW PSD_SIZE
DW 2
DW 1 << 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 NullSeg
DD GDT_SIZE
DD 0
times 24 DB 0
DQ 0
PSD_SIZE equ $ - ASM_PFX(gcPsd)
;
; CODE & DATA segments for SMM runtime
;
CODE_SEL equ CodeSeg64 - NullSeg
DATA_SEL equ DataSeg32 - NullSeg
CODE32_SEL equ CodeSeg32 - NullSeg
ASM_PFX(gcSmiGdtr):
DW GDT_SIZE - 1
DQ NullSeg
ASM_PFX(gcSmiIdtr):
DW 0
DQ 0
DEFAULT REL
SECTION .text
;------------------------------------------------------------------------------
; _SmiExceptionEntryPoints is the collection of exception entrypoints 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
;------------------------------------------------------------------------------
global ASM_PFX(PageFaultIdtHandlerSmmProfile)
ASM_PFX(PageFaultIdtHandlerSmmProfile):
push 0xe ; Page Fault
test spl, 8 ; odd multiple of 8 => ErrCode present
jnz .0
push qword [rsp] ; duplicate INT# if no ErrCode
mov qword [rsp + 8], 0
.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 [rbp + 48] ; RSP
push qword [rbp] ; RBP
push rsi
push rdi
;; UINT64 Gs, Fs, Es, Ds, Cs, Ss; insure high 16 bits of each is zero
movzx rax, word [rbp + 56]
push rax ; for ss
movzx rax, word [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 [rbp + 24]
;; UINT64 Gdtr[2], Idtr[2];
sub rsp, 16
sidt [rsp]
sub rsp, 16
sgdt [rsp]
;; UINT64 Ldtr, Tr;
xor rax, rax
str ax
push rax
sldt ax
push rax
;; UINT64 RFlags;
push qword [rbp + 40]
;; UINT64 Cr0, Cr1, Cr2, Cr3, Cr4, Cr8;
mov rax, cr8
push rax
mov rax, cr4
or rax, 0x208
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 0xf, 0xae, 00000111y ;fxsave [rdi]
; UEFI calling convention for x64 requires that Direction flag in EFLAGs is clear
cld
;; UINT32 ExceptionData;
push qword [rbp + 16]
;; call into exception handler
mov rcx, [rbp + 8]
mov rax, ASM_PFX(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 .1
.1:
;; UINT64 ExceptionData;
add rsp, 8
;; FX_SAVE_STATE_X64 FxSaveState;
mov rsi, rsp
db 0xf, 0xae, 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 [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 [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 [rbp + 32] ; for cs
pop qword [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 [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 [rsp + 40], 8 ;RFLAGS
pop rbp
add rsp, 16 ; skip INT# & ErrCode
iretq
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