diff options
Diffstat (limited to 'src/soc/amd/common/block/cpu/noncar/pre_c.S')
| -rw-r--r-- | src/soc/amd/common/block/cpu/noncar/pre_c.S | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/src/soc/amd/common/block/cpu/noncar/pre_c.S b/src/soc/amd/common/block/cpu/noncar/pre_c.S new file mode 100644 index 0000000000..6fae1ed1cb --- /dev/null +++ b/src/soc/amd/common/block/cpu/noncar/pre_c.S @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#include <cpu/x86/post_code.h> + +.global bootblock_resume_entry +bootblock_resume_entry: + post_code(0xb0) + + /* Get an early timestamp */ + rdtsc + movd %eax, %mm1 + movd %edx, %mm2 + + /* Fall through to bootblock_pre_c_entry */ + +/* + * on entry: + * mm0: BIST (ignored) + * mm2_mm1: timestamp at bootblock_protected_mode_entry + */ + +.global bootblock_pre_c_entry +bootblock_pre_c_entry: + post_code(0xa0) + + /* Clear .bss section */ + cld + xor %eax, %eax + movl $(_ebss), %ecx + movl $(_bss), %edi + sub %edi, %ecx + shrl $2, %ecx + rep stosl + + movl $_eearlyram_stack, %esp + + /* Align the stack and keep aligned for call to bootblock_c_entry() */ + and $0xfffffff0, %esp + sub $8, %esp + + movd %mm2, %eax + pushl %eax /* tsc[63:32] */ + movd %mm1, %eax + pushl %eax /* tsc[31:0] */ + + post_code(0xa2) + + call bootblock_c_entry + /* Never reached */ + +.halt_forever: + post_code(POST_DEAD_CODE) + hlt + jmp .halt_forever |