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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* This path is for stages that are post bootblock. The gdt is reloaded
* to accommodate platforms that are executing out of CAR. In order to
* continue with C code execution one needs to set stack pointer and
* clear .bss variables that are stage specific.
*/
#if CONFIG(RESET_VECTOR_IN_RAM)
#define _STACK_TOP _eearlyram_stack
#else
#define _STACK_TOP _ecar_stack
#endif
#if ENV_X86_64
.code64
#else
.code32
#endif
.section ".text._start", "ax", @progbits
.global _start
_start:
/* Migrate GDT to this text segment */
#if ENV_X86_64
call gdt_init64
#else
call gdt_init
#endif
/* reset stack pointer to CAR/EARLYRAM stack */
mov $_STACK_TOP, %esp
#if ENV_SEPARATE_DATA_AND_BSS
/* clear .bss section as it is not shared */
cld
xor %eax, %eax
movl $(_ebss), %ecx
movl $(_bss), %edi
sub %edi, %ecx
shrl $2, %ecx
rep stosl
/* Copy .data section content to Cache-As-Ram */
movl $(_edata), %ecx
movl $(_data), %edi
sub %edi, %ecx
shrl $2, %ecx
movl $(_data_load),%esi
rep movsl
#endif
#if ((ENV_SEPARATE_VERSTAGE && CONFIG(VERSTAGE_DEBUG_SPINLOOP)) \
|| (ENV_SEPARATE_ROMSTAGE && CONFIG(ROMSTAGE_DEBUG_SPINLOOP)))
/* Wait for a JTAG debugger to break in and set EBX non-zero */
xor %ebx, %ebx
debug_spinloop:
cmp $0, %ebx
jz debug_spinloop
#endif
andl $0xfffffff0, %esp
#if CONFIG(IDT_IN_EVERY_STAGE)
call exception_init
#endif
#if CONFIG(ASAN_IN_ROMSTAGE)
call asan_init
#endif
call car_stage_entry
/* Expect to never return. */
1:
jmp 1b
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