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| author | Bin Meng <bmeng.cn@gmail.com> | 2018-10-13 20:52:01 -0700 |
|---|---|---|
| committer | Bin Meng <bmeng.cn@gmail.com> | 2018-10-22 17:51:45 +0800 |
| commit | a139cc1865aa7dd14e896596fa23938b303d7052 (patch) | |
| tree | 259c05e98eec4ce02008bfa115544b4f687ab6dd | |
| parent | c74e3295ae4a5338f91e971aee1638fa08a9b97d (diff) | |
x86: Specify -march=core2 to build 64-bit U-Boot proper
With newer kernel.org GCC (7.3.0 or 8.1.0), the u-boot.rom image
built for qemu-x86_64 target does not boot. It keeps resetting
soon after the 32-bit SPL jumps to 64-bit proper. Debugging shows
that the reset happens inside env_callback_init().
000000000113dd85 <env_callback_init>:
113dd85: 41 54 push %r12
113dd87: 55 push %rbp
113dd88: 31 c0 xor %eax,%eax
113dd8a: 53 push %rbx
113dd8b: 0f 57 c0 xorps %xmm0,%xmm0
Executing "xorps %xmm0,%xmm0" causes CPU to immediately reset.
However older GCC like 5.4.0 (the one shipped by Ubuntu 16.04)
does not generate such instructions that utilizes SSE for this
function - env_callback_init() and U-Boot boots without any issue.
Explicitly specifying -march=core2 for newer GCC allows U-Boot
proper to boot again. Examine assembly codes of env_callback_init
and there is no SSE instruction in that function hence U-Boot
continues to boot.
core2 seems to be the oldest arch in GCC that supports 64-bit.
Like 32-bit U-Boot build we use -march=i386 which is the most
conservative cpu type so that the image can run on any x86
processor, let's do the same for the 64-bit U-Boot build.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
| -rw-r--r-- | arch/x86/config.mk | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/config.mk b/arch/x86/config.mk index cc940712a8..576501e55e 100644 --- a/arch/x86/config.mk +++ b/arch/x86/config.mk @@ -23,7 +23,7 @@ endif ifeq ($(IS_32BIT),y) PLATFORM_CPPFLAGS += -march=i386 -m32 else -PLATFORM_CPPFLAGS += $(if $(CONFIG_SPL_BUILD),,-fpic) -fno-common -m64 +PLATFORM_CPPFLAGS += $(if $(CONFIG_SPL_BUILD),,-fpic) -fno-common -march=core2 -m64 endif PLATFORM_RELFLAGS += -fdata-sections -ffunction-sections -fvisibility=hidden |