diff options
| author | Simon Glass | 2016-10-17 20:29:07 -0600 |
|---|---|---|
| committer | Bin Meng | 2016-10-18 15:58:50 +0800 |
| commit | f822403f0164be74a5161b65698d0f01f4556234 (patch) | |
| tree | accf57d30c4d04ae6daa0278f1d4358949dcba1f /arch/x86/cpu | |
| parent | 2b445e4d31940d512b3257f7398b794be710b8a9 (diff) | |
x86: Add implementations of setjmp() and longjmp()
Bring in these functions from Linux v4.4. They will be needed for EFI loader
support.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Diffstat (limited to 'arch/x86/cpu')
| -rw-r--r-- | arch/x86/cpu/Makefile | 2 | ||||
| -rw-r--r-- | arch/x86/cpu/setjmp.S | 61 |
2 files changed, 62 insertions, 1 deletions
diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile index 2667e0b478a..f5b8c9e3632 100644 --- a/arch/x86/cpu/Makefile +++ b/arch/x86/cpu/Makefile @@ -10,7 +10,7 @@ extra-y = start.o obj-$(CONFIG_X86_RESET_VECTOR) += resetvec.o start16.o -obj-y += interrupts.o cpu.o cpu_x86.o call64.o +obj-y += interrupts.o cpu.o cpu_x86.o call64.o setjmp.o AFLAGS_REMOVE_call32.o := -mregparm=3 \ $(if $(CONFIG_EFI_STUB_64BIT),-march=i386 -m32) diff --git a/arch/x86/cpu/setjmp.S b/arch/x86/cpu/setjmp.S new file mode 100644 index 00000000000..2ea1c6c7666 --- /dev/null +++ b/arch/x86/cpu/setjmp.S @@ -0,0 +1,61 @@ +/* + * Written by H. Peter Anvin <hpa@zytor.com> + * Brought in from Linux v4.4 and modified for U-Boot + * From Linux arch/um/sys-i386/setjmp.S + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#define _REGPARM + +/* + * The jmp_buf is assumed to contain the following, in order: + * %ebx + * %esp + * %ebp + * %esi + * %edi + * <return address> + */ + + .text + .align 4 + .globl setjmp + .type setjmp, @function +setjmp: +#ifdef _REGPARM + movl %eax, %edx +#else + movl 4(%esp), %edx +#endif + popl %ecx /* Return address, and adjust the stack */ + xorl %eax, %eax /* Return value */ + movl %ebx, (%edx) + movl %esp, 4(%edx) /* Post-return %esp! */ + pushl %ecx /* Make the call/return stack happy */ + movl %ebp, 8(%edx) + movl %esi, 12(%edx) + movl %edi, 16(%edx) + movl %ecx, 20(%edx) /* Return address */ + ret + + /* Provide function size if needed */ + .size setjmp, .-setjmp + + .align 4 + .globl longjmp + .type longjmp, @function +longjmp: +#ifdef _REGPARM + xchgl %eax, %edx +#else + movl 4(%esp), %edx /* jmp_ptr address */ +#endif + movl (%edx), %ebx + movl 4(%edx), %esp + movl 8(%edx), %ebp + movl 12(%edx), %esi + movl 16(%edx), %edi + jmp *20(%edx) + + .size longjmp, .-longjmp |