diff options
| -rw-r--r-- | payloads/libpayload/arch/x86/head.S | 31 | ||||
| -rw-r--r-- | payloads/libpayload/arch/x86/multiboot_header.inc | 54 |
2 files changed, 58 insertions, 27 deletions
diff --git a/payloads/libpayload/arch/x86/head.S b/payloads/libpayload/arch/x86/head.S index 2bac700bda..99842cd54b 100644 --- a/payloads/libpayload/arch/x86/head.S +++ b/payloads/libpayload/arch/x86/head.S @@ -38,36 +38,13 @@ * change anything. */ _entry: - jmp _init - - .align 4 - -#define MB_MAGIC 0x1BADB002 -#define MB_FLAGS 0x00010003 - -mb_header: - .long MB_MAGIC - .long MB_FLAGS - .long -(MB_MAGIC + MB_FLAGS) - .long mb_header - .long _start - .long _edata - .long _end - .long _init - -/* - * This function saves off the previous stack and switches us to our - * own execution environment. - */ -_init: - /* No interrupts, please. */ - cli + /* Add multiboot header and jump around it when building with multiboot support. */ #if CONFIG(LP_MULTIBOOT) - /* Store EAX and EBX */ - movl %eax, loader_eax - movl %ebx, loader_ebx + #include "multiboot_header.inc" #endif + /* No interrupts, please. */ + cli /* save pointer to coreboot tables */ movl 4(%esp), %eax diff --git a/payloads/libpayload/arch/x86/multiboot_header.inc b/payloads/libpayload/arch/x86/multiboot_header.inc new file mode 100644 index 0000000000..e321dc42b2 --- /dev/null +++ b/payloads/libpayload/arch/x86/multiboot_header.inc @@ -0,0 +1,54 @@ +/* + * + * Copyright (C) 2008 Advanced Micro Devices, Inc. + * Copyright (C) 2017 Patrick Rudolph <siro@das-labor.org> + * Copyright (C) 2024 Google Inc. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#define MB_MAGIC 0x1BADB002 +#define MB_FLAGS 0x00010003 + + jmp _init + +/* + * Note: The Multiboot standard requires Multiboot header to be placed + * below 0x2000 in the resulting image. See: + * http://www.gnu.org/software/grub/manual/multiboot/html_node/OS-image-format.html + */ +mb_header: + .long MB_MAGIC + .long MB_FLAGS + .long -(MB_MAGIC + MB_FLAGS) + .long mb_header + .long _start + .long _edata + .long _end + .long _init + +_init: + /* Store EAX and EBX */ + movl %eax, loader_eax + movl %ebx, loader_ebx |