On 10/18/14 20:25, Jordan Justen wrote: > The BaseTools/Scripts/ConvertMasmToNasm.py script was used to convert > X64/JumpToKernel.asm to X64/JumpToKernel.nasm > > Contributed-under: TianoCore Contribution Agreement 1.0 > Signed-off-by: Jordan Justen <[email protected]> > --- > OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf | 3 +- > OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S | 91 > ---------------------- > .../X64/{JumpToKernel.asm => JumpToKernel.nasm} | 66 ++++++++-------- > 3 files changed, 33 insertions(+), 127 deletions(-) > delete mode 100644 OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S > rename OvmfPkg/Library/LoadLinuxLib/X64/{JumpToKernel.asm => > JumpToKernel.nasm} (54%) > > diff --git a/OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf > b/OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf > index 0d98c26..12d2f4f 100644 > --- a/OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf > +++ b/OvmfPkg/Library/LoadLinuxLib/LoadLinuxLib.inf > @@ -34,8 +34,7 @@ > Ia32/JumpToKernel.nasm > > [Sources.X64] > - X64/JumpToKernel.asm > - X64/JumpToKernel.S > + X64/JumpToKernel.nasm > > [Packages] > MdePkg/MdePkg.dec > diff --git a/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S > b/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S > deleted file mode 100644 > index 056e3c0..0000000 > --- a/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.S > +++ /dev/null > @@ -1,91 +0,0 @@ > -#------------------------------------------------------------------------------ > -# > -# Copyright (c) 2006 - 2013, 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. > -# > -#------------------------------------------------------------------------------ > - > -ASM_GLOBAL ASM_PFX(JumpToKernel) > -ASM_GLOBAL ASM_PFX(JumpToUefiKernel) > - > -#------------------------------------------------------------------------------ > -# VOID > -# EFIAPI > -# JumpToKernel ( > -# VOID *KernelStart, // %rcx > -# VOID *KernelBootParams // %rdx > -# ); > -#------------------------------------------------------------------------------ > -ASM_PFX(JumpToKernel): > - > - // Set up for executing kernel. BP in %esi, entry point on the stack > - // (64-bit when the 'ret' will use it as 32-bit, but we're little-endian) > - movq %rdx, %rsi > - pushq %rcx > - > - // Jump into the compatibility mode CS > - pushq $0x10 > - leaq 1f(%rip), %rax > - pushq %rax > - .byte 0x48, 0xcb // retfq > - > -1: // Now in compatibility mode > -.code32 > - movl $0x18, %eax > - movl %eax, %ds > - movl %eax, %es > - movl %eax, %fs > - movl %eax, %gs > - movl %eax, %ss > - > - // Disable paging > - movl %cr0, %eax > - btcl $31, %eax > - movl %eax, %cr0 > - > - // Disable long mode in EFER > - movl $0x0c0000080, %ecx > - rdmsr > - btcl $8, %eax > - wrmsr > - > - // Disable PAE > - movl %cr4, %eax > - btcl $5, %eax > - movl %eax, %cr4 > - > - // Zero registers and 'return' to kernel > - xorl %ebp, %ebp > - xorl %edi, %edi > - xorl %ebx, %ebx > - ret > -.code64 > - > -#------------------------------------------------------------------------------ > -# VOID > -# EFIAPI > -# JumpToUefiKernel ( > -# EFI_HANDLE ImageHandle, // rcx > -# EFI_SYSTEM_TABLE *SystemTable, // rdx > -# VOID *KernelBootParams, // r8 > -# VOID *KernelStart // r9 > -# ); > -#------------------------------------------------------------------------------ > -ASM_PFX(JumpToUefiKernel): > - movq %rcx, %rdi > - movq %rdx, %rsi > - movq %r8, %rdx > - xor %rax, %rax > - movl 0x264(%r8), %eax > - addq %rax, %r9 > - addq $0x200, %r9 > - callq %r9 > - ret > - > diff --git a/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.asm > b/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.nasm > similarity index 54% > rename from OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.asm > rename to OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.nasm > index fc07eab..128dcef 100644 > --- a/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.asm > +++ b/OvmfPkg/Library/LoadLinuxLib/X64/JumpToKernel.nasm > @@ -12,7 +12,8 @@ > ; > > ;------------------------------------------------------------------------------ > > - .code > + DEFAULT REL > + SECTION .text > > > ;------------------------------------------------------------------------------ > ; VOID > @@ -22,7 +23,8 @@ > ; VOID *KernelBootParams // rdx > ; ); > > ;------------------------------------------------------------------------------ > -JumpToKernel PROC > +global ASM_PFX(JumpToKernel) > +ASM_PFX(JumpToKernel): > > ; Set up for executing kernel. BP in %esi, entry point on the stack > ; (64-bit when the 'ret' will use it as 32-bit, but we're little-endian) > @@ -30,43 +32,41 @@ JumpToKernel PROC > push rcx > > ; Jump into the compatibility mode CS > - push 10h > - lea rax, @F > + push 0x10 > + lea rax, [.0]
Okay, I did have to look at the .S here -- "@" is a label, "ahead" (F). And we're loading its rip-relative address into rax. I gather from the nasm docs that "." is the local label prefix. > push rax > - DB 048h, 0cbh ; retfq > + DB 0x48, 0xcb ; retfq > > -@@: > +.0: > ; Now in compatibility mode. > > - DB 0b8h, 018h, 000h, 000h, 000h ; movl $0x18, %eax > - DB 08eh, 0d8h ; movl %eax, %ds > - DB 08eh, 0c0h ; movl %eax, %es > - DB 08eh, 0e0h ; movl %eax, %fs > - DB 08eh, 0e8h ; movl %eax, %gs > - DB 08eh, 0d0h ; movl %eax, %ss > + DB 0xb8, 0x18, 0x0, 0x0, 0x0 ; movl $0x18, %eax > + DB 0x8e, 0xd8 ; movl %eax, %ds > + DB 0x8e, 0xc0 ; movl %eax, %es > + DB 0x8e, 0xe0 ; movl %eax, %fs > + DB 0x8e, 0xe8 ; movl %eax, %gs > + DB 0x8e, 0xd0 ; movl %eax, %ss I guess this could be "simply" rewritten, as nasm supports mode switches within the same assembly file. But the conversion looks okay too. > > ; Disable paging > - DB 00fh, 020h, 0c0h ; movl %cr0, %eax > - DB 00fh, 0bah, 0f8h, 01fh ; btcl $31, %eax > - DB 00fh, 022h, 0c0h ; movl %eax, %cr0 > + DB 0xf, 0x20, 0xc0 ; movl %cr0, %eax > + DB 0xf, 0xba, 0xf8, 0x1f ; btcl $31, %eax > + DB 0xf, 0x22, 0xc0 ; movl %eax, %cr0 > > ; Disable long mode in EFER > - DB 0b9h, 080h, 000h, 000h, 0c0h ; movl $0x0c0000080, %ecx > - DB 00fh, 032h ; rdmsr > - DB 00fh, 0bah, 0f8h, 008h ; btcl $8, %eax > - DB 00fh, 030h ; wrmsr > + DB 0xb9, 0x80, 0x0, 0x0, 0xc0 ; movl $0x0c0000080, %ecx > + DB 0xf, 0x32 ; rdmsr > + DB 0xf, 0xba, 0xf8, 0x8 ; btcl $8, %eax > + DB 0xf, 0x30 ; wrmsr > > ; Disable PAE > - DB 00fh, 020h, 0e0h ; movl %cr4, %eax > - DB 00fh, 0bah, 0f8h, 005h ; btcl $5, %eax > - DB 00fh, 022h, 0e0h ; movl %eax, %cr4 > + DB 0xf, 0x20, 0xe0 ; movl %cr4, %eax > + DB 0xf, 0xba, 0xf8, 0x5 ; btcl $5, %eax > + DB 0xf, 0x22, 0xe0 ; movl %eax, %cr4 > > - DB 031h, 0edh ; xor %ebp, %ebp > - DB 031h, 0ffh ; xor %edi, %edi > - DB 031h, 0dbh ; xor %ebx, %ebx > - DB 0c3h ; ret > - > -JumpToKernel ENDP > + DB 0x31, 0xed ; xor %ebp, %ebp > + DB 0x31, 0xff ; xor %edi, %edi > + DB 0x31, 0xdb ; xor %ebx, %ebx > + DB 0xc3 ; ret Comparing this by way of eyeballing gets old real quick. If it runs then the conversion is correct. :) Mode switches are not exactly forgiving. Also I think the conversion of DBs is a more "mechanic" part of ConvertMasmToNasm.py (around defineDataRe), and if it broke, it would break very loudly. > > > ;------------------------------------------------------------------------------ > ; VOID > @@ -78,18 +78,16 @@ JumpToKernel ENDP > ; VOID *KernelStart, // r9 > ; ); > > ;------------------------------------------------------------------------------ > -JumpToUefiKernel PROC > +global ASM_PFX(JumpToUefiKernel) > +ASM_PFX(JumpToUefiKernel): > > mov rdi, rcx > mov rsi, rdx > mov rdx, r8 > xor rax, rax > - mov eax, [r8 + 264h] > + mov eax, [r8 + 0x264] > add r9, rax > - add r9, 200h > + add r9, 0x200 > call r9 > ret > > -JumpToUefiKernel ENDP > - > -END > Reviewed-by: Laszlo Ersek <[email protected]> ------------------------------------------------------------------------------ _______________________________________________ edk2-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/edk2-devel
