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-rw-r--r--arch/x86_64/kernel/trampoline_64.S166
1 files changed, 0 insertions, 166 deletions
diff --git a/arch/x86_64/kernel/trampoline_64.S b/arch/x86_64/kernel/trampoline_64.S
deleted file mode 100644
index 607983b0d27..00000000000
--- a/arch/x86_64/kernel/trampoline_64.S
+++ /dev/null
@@ -1,166 +0,0 @@
-/*
- *
- * Trampoline.S Derived from Setup.S by Linus Torvalds
- *
- * 4 Jan 1997 Michael Chastain: changed to gnu as.
- * 15 Sept 2005 Eric Biederman: 64bit PIC support
- *
- * Entry: CS:IP point to the start of our code, we are
- * in real mode with no stack, but the rest of the
- * trampoline page to make our stack and everything else
- * is a mystery.
- *
- * In fact we don't actually need a stack so we don't
- * set one up.
- *
- * On entry to trampoline_data, the processor is in real mode
- * with 16-bit addressing and 16-bit data. CS has some value
- * and IP is zero. Thus, data addresses need to be absolute
- * (no relocation) and are taken with regard to r_base.
- *
- * With the addition of trampoline_level4_pgt this code can
- * now enter a 64bit kernel that lives at arbitrary 64bit
- * physical addresses.
- *
- * If you work on this file, check the object module with objdump
- * --full-contents --reloc to make sure there are no relocation
- * entries.
- */
-
-#include <linux/linkage.h>
-#include <asm/pgtable.h>
-#include <asm/page.h>
-#include <asm/msr.h>
-#include <asm/segment.h>
-
-.data
-
-.code16
-
-ENTRY(trampoline_data)
-r_base = .
- cli # We should be safe anyway
- wbinvd
- mov %cs, %ax # Code and data in the same place
- mov %ax, %ds
- mov %ax, %es
- mov %ax, %ss
-
-
- movl $0xA5A5A5A5, trampoline_data - r_base
- # write marker for master knows we're running
-
- # Setup stack
- movw $(trampoline_stack_end - r_base), %sp
-
- call verify_cpu # Verify the cpu supports long mode
- testl %eax, %eax # Check for return code
- jnz no_longmode
-
- mov %cs, %ax
- movzx %ax, %esi # Find the 32bit trampoline location
- shll $4, %esi
-
- # Fixup the vectors
- addl %esi, startup_32_vector - r_base
- addl %esi, startup_64_vector - r_base
- addl %esi, tgdt + 2 - r_base # Fixup the gdt pointer
-
- /*
- * GDT tables in non default location kernel can be beyond 16MB and
- * lgdt will not be able to load the address as in real mode default
- * operand size is 16bit. Use lgdtl instead to force operand size
- * to 32 bit.
- */
-
- lidtl tidt - r_base # load idt with 0, 0
- lgdtl tgdt - r_base # load gdt with whatever is appropriate
-
- xor %ax, %ax
- inc %ax # protected mode (PE) bit
- lmsw %ax # into protected mode
-
- # flush prefetch and jump to startup_32
- ljmpl *(startup_32_vector - r_base)
-
- .code32
- .balign 4
-startup_32:
- movl $__KERNEL_DS, %eax # Initialize the %ds segment register
- movl %eax, %ds
-
- xorl %eax, %eax
- btsl $5, %eax # Enable PAE mode
- movl %eax, %cr4
-
- # Setup trampoline 4 level pagetables
- leal (trampoline_level4_pgt - r_base)(%esi), %eax
- movl %eax, %cr3
-
- movl $MSR_EFER, %ecx
- movl $(1 << _EFER_LME), %eax # Enable Long Mode
- xorl %edx, %edx
- wrmsr
-
- xorl %eax, %eax
- btsl $31, %eax # Enable paging and in turn activate Long Mode
- btsl $0, %eax # Enable protected mode
- movl %eax, %cr0
-
- /*
- * At this point we're in long mode but in 32bit compatibility mode
- * with EFER.LME = 1, CS.L = 0, CS.D = 1 (and in turn
- * EFER.LMA = 1). Now we want to jump in 64bit mode, to do that we use
- * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
- */
- ljmp *(startup_64_vector - r_base)(%esi)
-
- .code64
- .balign 4
-startup_64:
- # Now jump into the kernel using virtual addresses
- movq $secondary_startup_64, %rax
- jmp *%rax
-
- .code16
-no_longmode:
- hlt
- jmp no_longmode
-#include "verify_cpu_64.S"
-
- # Careful these need to be in the same 64K segment as the above;
-tidt:
- .word 0 # idt limit = 0
- .word 0, 0 # idt base = 0L
-
- # Duplicate the global descriptor table
- # so the kernel can live anywhere
- .balign 4
-tgdt:
- .short tgdt_end - tgdt # gdt limit
- .long tgdt - r_base
- .short 0
- .quad 0x00cf9b000000ffff # __KERNEL32_CS
- .quad 0x00af9b000000ffff # __KERNEL_CS
- .quad 0x00cf93000000ffff # __KERNEL_DS
-tgdt_end:
-
- .balign 4
-startup_32_vector:
- .long startup_32 - r_base
- .word __KERNEL32_CS, 0
-
- .balign 4
-startup_64_vector:
- .long startup_64 - r_base
- .word __KERNEL_CS, 0
-
-trampoline_stack:
- .org 0x1000
-trampoline_stack_end:
-ENTRY(trampoline_level4_pgt)
- .quad level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
- .fill 510,8,0
- .quad level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
-
-ENTRY(trampoline_end)