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|
#------------------------------------------------------------------------------
#*
#* Copyright 2006, Intel Corporation
#* All rights reserved. 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:
.stack:
.code:
.org 0x21000
.equ DEFAULT_HANDLER_SIZE, INT1 - INT0
.macro jmpCommonIdtEntry
# 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...
.byte 0xe9 # jmp 16 bit relative
.long commonIdtEntry - . - 4 # offset to jump to
.endm
Start:
movl $0x001fffe8,%esp # make final stack aligned
# set OSFXSR and OSXMMEXCPT because some code will use XMM register
.byte 0xf
.byte 0x20
.byte 0xe0
# mov rax, cr4
btsl $9,%eax
btsl $0xa,%eax
.byte 0xf
.byte 0x22
.byte 0xe0
# mov cr4, rax
call ClearScreen
# Populate IDT with meaningful offsets for exception handlers...
sidt Idtr
movl Halt, %eax
movl %eax,%ebx # use bx to copy 15..0 to descriptors
shrl $16,%eax # use ax to copy 31..16 to descriptors
# 63..32 of descriptors is 0
movl $0x78,%ecx # 78h IDT entries to initialize with unique entry points (exceptions)
movl (Idtr + 2), %esi
movl (%esi),%edi
LOOP_1: # loop through all IDT entries exception handlers and initialize to default handler
movw %bx, (%edi) # write bits 15..0 of offset
movw $0x38, 2(%edi) # SYS_CODE_SEL64 from GDT
movw $(0x0e00 | 0x8000), 4(%edi) # type = 386 interrupt gate, present
movw %ax, 6(%edi) # write bits 31..16 of offset
movl $0, 8(%edi) # write bits 31..16 of offset
addl $16, %edi # move up to next descriptor
addw DEFAULT_HANDLER_SIZE, %bx # move to next entry point
loopl LOOP_1 # 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
movl $0x22000,%esi # esi = 22000
movl 0x14(%esi),%eax # eax = [22014]
addl %eax,%esi # esi = 22000 + [22014] = Base of EFILDR.C
movl 0x3c(%esi),%ebp # ebp = [22000 + [22014] + 3c] = NT Image Header for EFILDR.C
addl %esi,%ebp
movl 0x30(%ebp),%edi # edi = [[22000 + [22014] + 3c] + 2c] = ImageBase (63..32 is zero, ignore)
movl 0x28(%ebp),%eax # eax = [[22000 + [22014] + 3c] + 24] = EntryPoint
addl %edi,%eax # eax = ImageBase + EntryPoint
movl %ebx, EfiLdrOffset
movl %eax, (%ebx) # Modify far jump instruction for correct entry point
movw 6(%ebp), %bx # bx = Number of sections
xorl %eax,%eax
movw 0x14(%ebp), %ax # ax = Optional Header Size
addl %eax,%ebp
addl $0x18,%ebp # ebp = Start of 1st Section
SectionLoop:
pushl %esi # Save Base of EFILDR.C
pushl %edi # Save ImageBase
addl 0x14(%ebp),%esi # esi = Base of EFILDR.C + PointerToRawData
addl 0x0c(%ebp),%edi # edi = ImageBase + VirtualAddress
movl 0x10(%ebp),%ecx # ecs = SizeOfRawData
cld
shrl $2,%ecx
rep
movsl
popl %edi # Restore ImageBase
popl %esi # Restore Base of EFILDR.C
addw $0x28,%bp # ebp = ebp + 028h = Pointer to next section record
.byte 0x66
.byte 0xff
.byte 0xcb
# dec bx
cmpw $0,%bx
jne SectionLoop
movl (Idtr), %eax # get size of IDT
movzx (%edx), %eax
.byte 0xff
.byte 0xc0
# inc eax
addl 2(%edx), %eax # add to base of IDT to get location of memory map...
xorl %ecx,%ecx
movl %eax,%ecx # put argument to RCX
.byte 0x48
.byte 0xc7
.byte 0xc0
EfiLdrOffset:
.long 0x00401000 # Offset of EFILDR
# mov rax, 401000h
.byte 0x50
# push rax
# ret
.byte 0xc3
# db "**** DEFAULT IDT ENTRY ***",0
.align 0x2
Halt:
INT0:
pushl $0x0 # push error code place holder on the stack
pushl $0x0
jmpCommonIdtEntry
# db 0e9h ; jmp 16 bit reletive
# dd commonIdtEntry - $ - 4 ; offset to jump to
INT1:
pushl $0x0 # push error code place holder on the stack
pushl $0x1
jmpCommonIdtEntry
INT2:
pushl $0x0 # push error code place holder on the stack
pushl $0x2
jmpCommonIdtEntry
INT3:
pushl $0x0 # push error code place holder on the stack
pushl $0x3
jmpCommonIdtEntry
INT4:
pushl $0x0 # push error code place holder on the stack
pushl $0x4
jmpCommonIdtEntry
INT5:
pushl $0x0 # push error code place holder on the stack
pushl $0x5
jmpCommonIdtEntry
INT6:
pushl $0x0 # push error code place holder on the stack
pushl $0x6
jmpCommonIdtEntry
INT7:
pushl $0x0 # push error code place holder on the stack
pushl $0x7
jmpCommonIdtEntry
INT8:
# Double fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $0x8
jmpCommonIdtEntry
INT9:
pushl $0x0 # push error code place holder on the stack
pushl $0x9
jmpCommonIdtEntry
INT10:
# Invalid TSS causes an error code to be pushed so no phony push necessary
nop
nop
pushl $10
jmpCommonIdtEntry
INT11:
# Segment Not Present causes an error code to be pushed so no phony push necessary
nop
nop
pushl $11
jmpCommonIdtEntry
INT12:
# Stack fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $12
jmpCommonIdtEntry
INT13:
# GP fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $13
jmpCommonIdtEntry
INT14:
# Page fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $14
jmpCommonIdtEntry
INT15:
pushl $0x0 # push error code place holder on the stack
pushl $15
jmpCommonIdtEntry
INT16:
pushl $0x0 # push error code place holder on the stack
pushl $16
jmpCommonIdtEntry
INT17:
# Alignment check causes an error code to be pushed so no phony push necessary
nop
nop
pushl $17
jmpCommonIdtEntry
INT18:
pushl $0x0 # push error code place holder on the stack
pushl $18
jmpCommonIdtEntry
INT19:
pushl $0x0 # push error code place holder on the stack
pushl $19
jmpCommonIdtEntry
INTUnknown:
.rept (0x78 - 20)
pushl $0x0 # push error code place holder on the stack
# push xxh ; push vector number
.byte 0x6a
.byte ( . - INTUnknown - 3 ) / 9 + 20 # vector number
jmpCommonIdtEntry
.endr
commonIdtEntry:
pushl %eax
pushl %ecx
pushl %edx
pushl %ebx
pushl %esp
pushl %ebp
pushl %esi
pushl %edi
.byte 0x41
.byte 0x50
# push r8
.byte 0x41
.byte 0x51
# push r9
.byte 0x41
.byte 0x52
# push r10
.byte 0x41
.byte 0x53
# push r11
.byte 0x41
.byte 0x54
# push r12
.byte 0x41
.byte 0x55
# push r13
.byte 0x41
.byte 0x56
# push r14
.byte 0x41
.byte 0x57
# push r15
.byte 0x48
movl %esp,%ebp
# 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 String1, %esi
call PrintString
.byte 0x48
movl 16*8(%ebp),%eax ## move Int number into RAX
.byte 0x48
cmpl $18,%eax
ja PrintDefaultString
PrintExceptionString:
shll $3,%eax ## multiply by 8 to get offset from StringTable to actual string address
addl StringTable, %eax
movl (%eax),%esi
jmp PrintTheString
PrintDefaultString:
movl IntUnknownString, %esi
# patch Int number
movl %eax,%edx
call A2C
movb %al,1(%esi)
movl %edx,%eax
shrl $4,%eax
call A2C
movb %al,(%esi)
PrintTheString:
call PrintString
movl String2, %esi
call PrintString
.byte 0x48
movl 19*8(%ebp),%eax # CS
call PrintQword
movb $':', %al
movb %al, (%edi)
addl $2,%edi
.byte 0x48
movl 18*8(%ebp),%eax # RIP
call PrintQword
movl String3, %esi
call PrintString
movl $0xb8140,%edi
movl StringRax, %esi
call PrintString
.byte 0x48
movl 15*8(%ebp),%eax
call PrintQword
movl StringRcx, %esi
call PrintString
.byte 0x48
movl 14*8(%ebp),%eax
call PrintQword
movl StringRdx, %esi
call PrintString
.byte 0x48
movl 13*8(%ebp),%eax
call PrintQword
movl $0xb81e0,%edi
movl StringRbx, %esi
call PrintString
.byte 0x48
movl 12*8(%ebp),%eax
call PrintQword
movl StringRsp, %esi
call PrintString
.byte 0x48
movl 21*8(%ebp),%eax
call PrintQword
movl StringRbp, %esi
call PrintString
.byte 0x48
movl 10*8(%ebp),%eax
call PrintQword
movl $0xb8280,%edi
movl StringRsi, %esi
call PrintString
.byte 0x48
movl 9*8(%ebp),%eax
call PrintQword
movl StringRdi, %esi
call PrintString
.byte 0x48
movl 8*8(%ebp),%eax
call PrintQword
movl StringEcode, %esi
call PrintString
.byte 0x48
movl 17*8(%ebp),%eax
call PrintQword
movl $0xb8320,%edi
movl StringR8, %esi
call PrintString
.byte 0x48
movl 7*8(%ebp),%eax
call PrintQword
movl StringR9, %esi
call PrintString
.byte 0x48
movl 6*8(%ebp),%eax
call PrintQword
movl StringR10, %esi
call PrintString
.byte 0x48
movl 5*8(%ebp),%eax
call PrintQword
movl $0xb83c0,%edi
movl StringR11, %esi
call PrintString
.byte 0x48
movl 4*8(%ebp),%eax
call PrintQword
movl StringR12, %esi
call PrintString
.byte 0x48
movl 3*8(%ebp),%eax
call PrintQword
movl StringR13, %esi
call PrintString
.byte 0x48
movl 2*8(%ebp),%eax
call PrintQword
movl $0xb8460,%edi
movl StringR14, %esi
call PrintString
.byte 0x48
movl 1*8(%ebp),%eax
call PrintQword
movl StringR15, %esi
call PrintString
.byte 0x48
movl 0*8(%ebp),%eax
call PrintQword
movl StringSs, %esi
call PrintString
.byte 0x48
movl 22*8(%ebp),%eax
call PrintQword
movl $0xb8500,%edi
movl StringRflags, %esi
call PrintString
.byte 0x48
movl 20*8(%ebp),%eax
call PrintQword
movl $0xb8640,%edi
movl %ebp,%esi
addl $23*8,%esi
movl $4,%ecx
OuterLoop:
pushl %ecx
movl $4,%ecx
.byte 0x48
movl %edi,%edx
InnerLoop:
.byte 0x48
movl (%esi),%eax
call PrintQword
addl $8,%esi
mov $0x00, %al
movb %al,(%edi)
addl $2,%edi
loop InnerLoop
popl %ecx
addl $0xa0,%edx
movl %edx,%edi
loop OuterLoop
movl $0xb8960,%edi
.byte 0x48
movl 18*8(%ebp),%eax # RIP
subl $8*8,%eax
.byte 0x48
movl %eax,%esi # esi = rip - 8 QWORD linear (total 16 QWORD)
movl $4,%ecx
OuterLoop1:
pushl %ecx
movl $4,%ecx
movl %edi,%edx
InnerLoop1:
.byte 0x48
movl (%esi),%eax
call PrintQword
addl $8,%esi
movb $0x00, %al
movb %al,(%edi)
addl $2,%edi
loop InnerLoop1
popl %ecx
addl $0xa0,%edx
movl %edx,%edi
loop OuterLoop1
#wbinvd
LN_C1:
jmp LN_C1
#
# return
#
movl %ebp,%esp
# mov rsp, rbp
.byte 0x41
.byte 0x5f
# pop r15
.byte 0x41
.byte 0x5e
# pop r14
.byte 0x41
.byte 0x5d
# pop r13
.byte 0x41
.byte 0x5c
# pop r12
.byte 0x41
.byte 0x5b
# pop r11
.byte 0x41
.byte 0x5a
# pop r10
.byte 0x41
.byte 0x59
# pop r9
.byte 0x41
.byte 0x58
# pop r8
popl %edi
popl %esi
popl %ebp
popl %eax # esp
popl %ebx
popl %edx
popl %ecx
popl %eax
.byte 0x48
.byte 0x83
.byte 0xc4
.byte 0x10
# add esp, 16 ; error code and INT number
.byte 0x48
.byte 0xcf
# iretq
PrintString:
pushl %eax
LN_C2:
movb (%esi), %al
cmpb $0,%al
je LN_C3
movb %al, (%edi)
.byte 0xff
.byte 0xc6
# inc esi
addl $2,%edi
jmp LN_C2
LN_C3:
popl %eax
ret
## RAX contains qword to print
## RDI contains memory location (screen location) to print it to
PrintQword:
pushl %ecx
pushl %ebx
pushl %eax
.byte 0x48
.byte 0xc7
.byte 0xc1
.long 16
# mov rcx, 16
looptop:
.byte 0x48
roll $4,%eax
movb %al,%bl
andb $0xf,%bl
addb $'0', %bl
cmpb $'9', %bl
jle @f
addb $7,%bl
@@:
movb %bl, (%edi)
addl $2,%edi
loop looptop
#wbinvd
popl %eax
popl %ebx
popl %ecx
ret
ClearScreen:
pushl %eax
pushl %ecx
movb $0x00, %al
movb $0xc,%ah
movl $0xb8000,%edi
movl $80*24,%ecx
LN_C4:
movw %ax, (%edi)
addl $2,%edi
loop LN_C4
movl $0xb8000,%edi
popl %ecx
popl %eax
ret
A2C:
andb $0xf,%al
addb $'0', %al
cmpb $'9', %al
jle @f
addb $7,%al
LN_C5:
ret
String1: .asciz "*** INT "
Int0String: .asciz "00h Divide by 0 -"
Int1String: .asciz "01h Debug exception -"
Int2String: .asciz "02h NMI -"
Int3String: .asciz "03h Breakpoint -"
Int4String: .asciz "04h Overflow -"
Int5String: .asciz "05h Bound -"
Int6String: .asciz "06h Invalid opcode -"
Int7String: .asciz "07h Device not available -"
Int8String: .asciz "08h Double fault -"
Int9String: .asciz "09h Coprocessor seg overrun (reserved) -"
Int10String: .asciz "0Ah Invalid TSS -"
Int11String: .asciz "0Bh Segment not present -"
Int12String: .asciz "0Ch Stack fault -"
Int13String: .asciz "0Dh General protection fault -"
Int14String: .asciz "0Eh Page fault -"
Int15String: .asciz "0Fh (Intel reserved) -"
Int16String: .asciz "10h Floating point error -"
Int17String: .asciz "11h Alignment check -"
Int18String: .asciz "12h Machine check -"
Int19String: .asciz "13h SIMD Floating-Point Exception -"
IntUnknownString: .asciz "??h Unknown interrupt -"
StringTable: .long Int0String, Int1String, Int2String, Int3String, \
Int4String, Int5String, Int6String, Int7String, \
Int8String, Int9String, Int10String, Int11String, \
Int12String, Int13String, Int14String, Int15String,\
Int16String, Int17String, Int18String, Int19String
String2: .asciz " HALT!! *** ("
String3: .asciz ")"
StringRax: .asciz "RAX="
StringRcx: .asciz " RCX="
StringRdx: .asciz " RDX="
StringRbx: .asciz "RBX="
StringRsp: .asciz " RSP="
StringRbp: .asciz " RBP="
StringRsi: .asciz "RSI="
StringRdi: .asciz " RDI="
StringEcode: .asciz " ECODE="
StringR8: .asciz "R8 ="
StringR9: .asciz " R9 ="
StringR10: .asciz " R10="
StringR11: .asciz "R11="
StringR12: .asciz " R12="
StringR13: .asciz " R13="
StringR14: .asciz "R14="
StringR15: .asciz " R15="
StringSs: .asciz " SS ="
StringRflags: .asciz "RFLAGS="
Idtr: .float 0
.float 0
.org 0x21ffe
BlockSignature:
.word 0xaa55
|
