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#include <xtf/asm_macros.h>

#include <arch/page.h>
#include <arch/processor.h>
#include <arch/msr-index.h>
#include <arch/segment.h>

#include <xen/elfnote.h>

        .section ".text.head", "ax", @progbits
        .code32                 /* Always starts in 32bit flat mode. */
GLOBAL(_elf_start)              /* HVM common setup. */

#if CONFIG_PAGING_LEVELS > 0    /* Paging setup for CR3 and CR4 */

#if CONFIG_PAGING_LEVELS == 2
        mov $X86_CR4_PSE, %eax
#elif CONFIG_PAGING_LEVELS == 3 || CONFIG_PAGING_LEVELS == 4
        mov $X86_CR4_PAE, %eax
#else
# error Bad paging mode
#endif
        mov %eax, %cr4

        mov $cr3_target, %ebx
        mov %ebx, %cr3
#endif /* CONFIG_PAGING_LEVELS > 0 */

#ifdef __x86_64__               /* EFER.LME = 1 */
        mov $MSR_EFER, %ecx
        rdmsr
        or  $EFER_LME, %eax
        wrmsr
#endif /* __x86_64__ */

#if CONFIG_PAGING_LEVELS > 0    /* CR0.PG = 1 */
# define MAYBE_PG X86_CR0_PG
#else
# define MAYBE_PG 0
#endif /* CONFIG_PAGING_LEVELS > 0 */

        mov %cr0, %eax
        or $(X86_CR0_WP | MAYBE_PG), %eax
        mov %eax, %cr0

        lgdt gdt_ptr

        /* Load code segment. */
        ljmp $__KERN_CS, $1f
#ifdef __x86_64__
        .code64
#endif

        /* Load data segments. */
1:      mov $__USER_DS, %eax
        mov %eax, %ds
        mov %eax, %es
        mov %eax, %fs
        mov %eax, %gs
        mov $__KERN_DS, %eax
        mov %eax, %ss

        /* Move onto the boot stack. */
        mov $boot_stack + PAGE_SIZE, %esp

        /* Reset flags. */
        push $X86_EFLAGS_MBS
        popf

        call xtf_main

        /* panic() if xtf_main manages to return. */
#ifdef __x86_64__
        lea .Lmain_err_msg(%rip), %rdi
#else
        push $.Lmain_err_msg
#endif
        call panic
ENDFUNC(_elf_start)

DECLSTR(.Lmain_err_msg, "xtf_main() returned\n")

/* All HVM XTF guests are compatible with the PVH ABI. */
ENTRY(_pvh_start)
        mov %ebx, pvh_start_info
        jmp _elf_start
ENDFUNC(_pvh_start)
ELFNOTE(Xen, XEN_ELFNOTE_PHYS32_ENTRY, .long _pvh_start)

/*
 * Local variables:
 * tab-width: 8
 * indent-tabs-mode: nil
 * End:
 */