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;------------------------------------------------------------------------------ ;
; Copyright (c) 2015 - 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:
;
; MpFuncs.nasm
;
; Abstract:
;
; This is the assembly code for MP support
;
;-------------------------------------------------------------------------------
%include "MpEqu.inc"
extern ASM_PFX(InitializeFloatingPointUnits)
DEFAULT REL
SECTION .text
;-------------------------------------------------------------------------------------
;RendezvousFunnelProc procedure follows. All APs execute their procedure. This
;procedure serializes all the AP processors through an Init sequence. It must be
;noted that APs arrive here very raw...ie: real mode, no stack.
;ALSO THIS PROCEDURE IS EXECUTED BY APs ONLY ON 16 BIT MODE. HENCE THIS PROC
;IS IN MACHINE CODE.
;-------------------------------------------------------------------------------------
global ASM_PFX(RendezvousFunnelProc)
ASM_PFX(RendezvousFunnelProc):
RendezvousFunnelProcStart:
; At this point CS = 0x(vv00) and ip= 0x0.
; Save BIST information to ebp firstly
BITS 16
mov ebp, eax ; Save BIST information
mov ax, cs
mov ds, ax
mov es, ax
mov ss, ax
xor ax, ax
mov fs, ax
mov gs, ax
mov si, BufferStartLocation
mov ebx, [si]
mov di, ModeOffsetLocation
mov eax, [di]
mov di, CodeSegmentLocation
mov edx, [di]
mov di, ax
sub di, 02h
mov [di],dx ; Patch long mode CS
sub di, 04h
add eax, ebx
mov [di],eax ; Patch address
mov si, GdtrLocation
o32 lgdt [cs:si]
mov si, IdtrLocation
o32 lidt [cs:si]
mov di, DataSegmentLocation
mov edi, [di] ; Save long mode DS in edi
mov si, Cr3Location ; Save CR3 in ecx
mov ecx, [si]
xor ax, ax
mov ds, ax ; Clear data segment
mov eax, cr0 ; Get control register 0
or eax, 000000003h ; Set PE bit (bit #0) & MP
mov cr0, eax
mov eax, cr4
bts eax, 5
mov cr4, eax
mov cr3, ecx ; Load CR3
mov ecx, 0c0000080h ; EFER MSR number
rdmsr ; Read EFER
bts eax, 8 ; Set LME=1
wrmsr ; Write EFER
mov eax, cr0 ; Read CR0
bts eax, 31 ; Set PG=1
mov cr0, eax ; Write CR0
jmp 0:strict dword 0 ; far jump to long mode
BITS 64
LongModeStart:
mov eax, edi
mov ds, ax
mov es, ax
mov ss, ax
mov esi, ebx
mov edi, esi
add edi, LockLocation
mov rax, NotVacantFlag
TestLock:
xchg qword [edi], rax
cmp rax, NotVacantFlag
jz TestLock
mov edi, esi
add edi, NumApsExecutingLoction
inc dword [edi]
mov ebx, [edi]
ProgramStack:
mov edi, esi
add edi, StackSizeLocation
mov rax, qword [edi]
mov edi, esi
add edi, StackStartAddressLocation
add rax, qword [edi]
mov rsp, rax
mov qword [edi], rax
Releaselock:
mov rax, VacantFlag
mov edi, esi
add edi, LockLocation
xchg qword [edi], rax
CProcedureInvoke:
push rbp ; push BIST data at top of AP stack
xor rbp, rbp ; clear ebp for call stack trace
push rbp
mov rbp, rsp
mov rax, ASM_PFX(InitializeFloatingPointUnits)
sub rsp, 20h
call rax ; Call assembly function to initialize FPU per UEFI spec
add rsp, 20h
mov edx, ebx ; edx is NumApsExecuting
mov ecx, esi
add ecx, LockLocation ; rcx is address of exchange info data buffer
mov edi, esi
add edi, ApProcedureLocation
mov rax, qword [edi]
sub rsp, 20h
call rax ; invoke C function
add rsp, 20h
jmp $
RendezvousFunnelProcEnd:
;-------------------------------------------------------------------------------------
; AsmGetAddressMap (&AddressMap);
;-------------------------------------------------------------------------------------
global ASM_PFX(AsmGetAddressMap)
ASM_PFX(AsmGetAddressMap):
mov rax, ASM_PFX(RendezvousFunnelProc)
mov qword [rcx], rax
mov qword [rcx + 8h], LongModeStart - RendezvousFunnelProcStart
mov qword [rcx + 10h], RendezvousFunnelProcEnd - RendezvousFunnelProcStart
ret
;-------------------------------------------------------------------------------------
;AsmExchangeRole procedure follows. This procedure executed by current BSP, that is
;about to become an AP. It switches it'stack with the current AP.
;AsmExchangeRole (IN CPU_EXCHANGE_INFO *MyInfo, IN CPU_EXCHANGE_INFO *OthersInfo);
;-------------------------------------------------------------------------------------
global ASM_PFX(AsmExchangeRole)
ASM_PFX(AsmExchangeRole):
; DO NOT call other functions in this function, since 2 CPU may use 1 stack
; at the same time. If 1 CPU try to call a function, stack will be corrupted.
push rax
push rbx
push rcx
push rdx
push rsi
push rdi
push rbp
push r8
push r9
push r10
push r11
push r12
push r13
push r14
push r15
mov rax, cr0
push rax
mov rax, cr4
push rax
; rsi contains MyInfo pointer
mov rsi, rcx
; rdi contains OthersInfo pointer
mov rdi, rdx
;Store EFLAGS, GDTR and IDTR regiter to stack
pushfq
sgdt [rsi + 16]
sidt [rsi + 26]
; Store the its StackPointer
mov [rsi + 8], rsp
; update its switch state to STORED
mov byte [rsi], CPU_SWITCH_STATE_STORED
WaitForOtherStored:
; wait until the other CPU finish storing its state
cmp byte [rdi], CPU_SWITCH_STATE_STORED
jz OtherStored
pause
jmp WaitForOtherStored
OtherStored:
; Since another CPU already stored its state, load them
; load GDTR value
lgdt [rdi + 16]
; load IDTR value
lidt [rdi + 26]
; load its future StackPointer
mov rsp, [rdi + 8]
; update the other CPU's switch state to LOADED
mov byte [rdi], CPU_SWITCH_STATE_LOADED
WaitForOtherLoaded:
; wait until the other CPU finish loading new state,
; otherwise the data in stack may corrupt
cmp byte [rsi], CPU_SWITCH_STATE_LOADED
jz OtherLoaded
pause
jmp WaitForOtherLoaded
OtherLoaded:
; since the other CPU already get the data it want, leave this procedure
popfq
pop rax
mov cr4, rax
pop rax
mov cr0, rax
pop r15
pop r14
pop r13
pop r12
pop r11
pop r10
pop r9
pop r8
pop rbp
pop rdi
pop rsi
pop rdx
pop rcx
pop rbx
pop rax
ret
|
