HelenOS sources
#
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# - Redistributions in binary form must reproduce the above copyright
# - The name of the author may not be used to endorse or promote products
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#include <abi/asmtool.h>
#include <arch/boot/boot.h>
#include <arch/boot/memmap.h>
#include <arch/mm/page.h>
#include <arch/pm.h>
#include <arch/cpu.h>
#include <arch/cpuid.h>
#include <arch/context_struct.h>
.section K_TEXT_START, "ax"
#ifdef CONFIG_SMP
.align 4096
SYMBOL(unmapped_ap_boot)
.code16
cli
xorw %ax, %ax
movw %ax, %ds
lgdtl ap_gdtr # initialize Global Descriptor Table register
movl %cr0, %eax
orl $CR0_PE, %eax
movl %eax, %cr0 # switch to protected mode
jmpl $GDT_SELECTOR(KTEXT32_DES), $jump_to_kernel - BOOT_OFFSET + AP_BOOT_OFFSET
jump_to_kernel:
.code32
movw $GDT_SELECTOR(KDATA_DES), %ax
movw %ax, %ds
movw %ax, %es
movw %ax, %ss
movw $GDT_SELECTOR(UDATA_DES), %ax
movw %ax, %gs
movl %cr4, %eax
orl $CR4_PAE, %eax
movl %eax, %cr4
leal ptl_0, %eax
movl %eax, %cr3
movl $AMD_MSR_EFER, %ecx # EFER MSR number
rdmsr # Read EFER
orl $AMD_LME, %eax # Set LME=1
wrmsr # Write EFER
movl %cr0, %eax
orl $CR0_PG, %eax
movl %eax, %cr0
jmpl $GDT_SELECTOR(KTEXT_DES), $start64 - BOOT_OFFSET + AP_BOOT_OFFSET
.code64
start64:
movabsq $bootstrap_stack_top, %rsp
movq (%rsp), %rsp
pushq $0
pushq $0
movq %rsp, %rbp
movabsq $main_ap, %rax
callq *%rax # never returns
#endif
.section K_DATA_START, "aw", @progbits
#ifdef CONFIG_SMP
SYMBOL(unmapped_ap_gdtr)
.word 0
.long 0
#endif
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