On 26.09.16 09:00, Bin Meng wrote: > Hi Simon, > > On Mon, Sep 26, 2016 at 5:27 AM, Simon Glass <s...@chromium.org> wrote: >> Bring in these functions from Linux v4.4. They will be needed for EFI loader >> support. >> >> Signed-off-by: Simon Glass <s...@chromium.org> >> --- >> >> Changes in v2: >> - Drop irrelevant comment >> - Add a comment about .size >> - Drop unnecessary .text directive >> - Make longjmp() always cause setjmp() to return 1 >> >> arch/x86/cpu/Makefile | 2 +- >> arch/x86/cpu/setjmp.S | 66 >> +++++++++++++++++++++++++++++++++++++++++++ >> arch/x86/include/asm/setjmp.h | 24 ++++++++++++++++ >> 3 files changed, 91 insertions(+), 1 deletion(-) >> create mode 100644 arch/x86/cpu/setjmp.S >> create mode 100644 arch/x86/include/asm/setjmp.h >> >> diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile >> index 2667e0b..f5b8c9e 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 0000000..7443274 >> --- /dev/null >> +++ b/arch/x86/cpu/setjmp.S >> @@ -0,0 +1,66 @@ >> +/* >> + * Written by H. Peter Anvin <h...@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 >> + */ >> + >> +#include <asm/global_data.h> >> +#include <asm/msr-index.h> >> +#include <asm/processor-flags.h> >> + > > I believe the above 3 includes are not needed. > >> +#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 1, %eax > > This should be $1. > > But I still think the setjmp/longjump codes in efi_loader is wrong. We > should have longjump() to pass the return value to setjmp().
Why? Where's the difference? Alex _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
