diff options
Diffstat (limited to 'arch/x86/kernel/acpi/realmode/wakeup.S')
| -rw-r--r-- | arch/x86/kernel/acpi/realmode/wakeup.S | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.S b/arch/x86/kernel/acpi/realmode/wakeup.S new file mode 100644 index 000000000000..f9b77fb37e5b --- /dev/null +++ b/arch/x86/kernel/acpi/realmode/wakeup.S @@ -0,0 +1,113 @@ +/* + * ACPI wakeup real mode startup stub + */ +#include <asm/segment.h> +#include <asm/msr-index.h> +#include <asm/page.h> +#include <asm/pgtable.h> + + .code16 + .section ".header", "a" + +/* This should match the structure in wakeup.h */ + .globl wakeup_header +wakeup_header: +video_mode: .short 0 /* Video mode number */ +pmode_return: .byte 0x66, 0xea /* ljmpl */ + .long 0 /* offset goes here */ + .short __KERNEL_CS +pmode_cr0: .long 0 /* Saved %cr0 */ +pmode_cr3: .long 0 /* Saved %cr3 */ +pmode_cr4: .long 0 /* Saved %cr4 */ +pmode_efer: .quad 0 /* Saved EFER */ +pmode_gdt: .quad 0 +realmode_flags: .long 0 +real_magic: .long 0 +trampoline_segment: .word 0 +signature: .long 0x51ee1111 + + .text + .globl _start + .code16 +wakeup_code: +_start: + cli + cld + + /* Set up segments */ + movw %cs, %ax + movw %ax, %ds + movw %ax, %es + movw %ax, %ss + + movl $wakeup_stack_end, %esp + + /* Clear the EFLAGS */ + pushl $0 + popfl + + /* Check header signature... */ + movl signature, %eax + cmpl $0x51ee1111, %eax + jne bogus_real_magic + + /* Check we really have everything... */ + movl end_signature, %eax + cmpl $0x65a22c82, %eax + jne bogus_real_magic + + /* Call the C code */ + calll main + + /* Do any other stuff... */ + +#ifndef CONFIG_64BIT + /* This could also be done in C code... */ + movl pmode_cr3, %eax + movl %eax, %cr3 + + movl pmode_cr4, %ecx + jecxz 1f + movl %ecx, %cr4 +1: + movl pmode_efer, %eax + movl pmode_efer + 4, %edx + movl %eax, %ecx + orl %edx, %ecx + jz 1f + movl $0xc0000080, %ecx + wrmsr +1: + + lgdtl pmode_gdt + + /* This really couldn't... */ + movl pmode_cr0, %eax + movl %eax, %cr0 + jmp pmode_return +#else + pushw $0 + pushw trampoline_segment + pushw $0 + lret +#endif + +bogus_real_magic: +1: + hlt + jmp 1b + + .data + .balign 4 + .globl HEAP, heap_end +HEAP: + .long wakeup_heap +heap_end: + .long wakeup_stack + + .bss +wakeup_heap: + .space 2048 +wakeup_stack: + .space 2048 +wakeup_stack_end: |