diff options
| author | Jarkko Sakkinen <jarkko.sakkinen@intel.com> | 2012-05-08 21:22:46 +0300 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-05-08 15:04:27 -0700 |
| commit | cda846f101fb1396b6924f1d9b68ac3d42de5403 (patch) | |
| tree | 1fa8716c308b8e10156a1caf51d8ff6c98eceea9 /arch/x86/realmode | |
| parent | bf8b88e97716feb750c3d34492f00d9c085e1183 (diff) | |
x86, realmode: read cr4 and EFER from kernel for 64-bit trampoline
This patch changes 64-bit trampoline so that CR4 and
EFER are provided by the kernel instead of using fixed
values.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-24-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/realmode')
| -rw-r--r-- | arch/x86/realmode/rm/header.S | 1 | ||||
| -rw-r--r-- | arch/x86/realmode/rm/trampoline_64.S | 32 | ||||
| -rw-r--r-- | arch/x86/realmode/rm/trampoline_common.S | 19 |
3 files changed, 27 insertions, 25 deletions
diff --git a/arch/x86/realmode/rm/header.S b/arch/x86/realmode/rm/header.S index b4c32632bf16..4612d5382791 100644 --- a/arch/x86/realmode/rm/header.S +++ b/arch/x86/realmode/rm/header.S @@ -9,6 +9,7 @@ .section ".header", "a" + .balign 16 GLOBAL(real_mode_header) .long pa_text_start .long pa_ro_end diff --git a/arch/x86/realmode/rm/trampoline_64.S b/arch/x86/realmode/rm/trampoline_64.S index 3f7293239365..66e26f088288 100644 --- a/arch/x86/realmode/rm/trampoline_64.S +++ b/arch/x86/realmode/rm/trampoline_64.S @@ -34,9 +34,9 @@ #include "realmode.h" .text - .balign PAGE_SIZE .code16 + .balign PAGE_SIZE ENTRY(trampoline_start) cli # We should be safe anyway wbinvd @@ -65,8 +65,8 @@ ENTRY(trampoline_start) * to 32 bit. */ - lidtl tidt # load idt with 0, 0 - lgdtl tgdt # load gdt with whatever is appropriate + lidtl tr_idt # load idt with 0, 0 + lgdtl tr_gdt # load gdt with whatever is appropriate movw $__KERNEL_DS, %dx # Data segment descriptor @@ -93,16 +93,17 @@ ENTRY(startup_32) movl %edx, %fs movl %edx, %gs - movl $X86_CR4_PAE, %eax + movl pa_tr_cr4, %eax movl %eax, %cr4 # Enable PAE mode # Setup trampoline 4 level pagetables movl $pa_trampoline_pgd, %eax movl %eax, %cr3 + # Set up EFER + movl pa_tr_efer, %eax + movl pa_tr_efer + 4, %edx movl $MSR_EFER, %ecx - movl $((1 << _EFER_LME) | (1 << _EFER_NX)), %eax # Enable Long Mode - xorl %edx, %edx wrmsr # Enable paging and in turn activate Long Mode @@ -124,23 +125,4 @@ ENTRY(startup_64) # Now jump into the kernel using virtual addresses jmpq *tr_start(%rip) - .section ".rodata","a" - .balign 16 -tidt: - .word 0 # idt limit = 0 - .word 0, 0 # idt base = 0L - - # Duplicate the global descriptor table - # so the kernel can live anywhere - .balign 16 - .globl tgdt -tgdt: - .short tgdt_end - tgdt - 1 # gdt limit - .long pa_tgdt - .short 0 - .quad 0x00cf9b000000ffff # __KERNEL32_CS - .quad 0x00af9b000000ffff # __KERNEL_CS - .quad 0x00cf93000000ffff # __KERNEL_DS -tgdt_end: - #include "trampoline_common.S" diff --git a/arch/x86/realmode/rm/trampoline_common.S b/arch/x86/realmode/rm/trampoline_common.S index c3f951c468c5..cac444b942f8 100644 --- a/arch/x86/realmode/rm/trampoline_common.S +++ b/arch/x86/realmode/rm/trampoline_common.S @@ -1,5 +1,20 @@ .section ".rodata","a" +#ifdef CONFIG_X86_64 + # Duplicate the global descriptor table + # so the kernel can live anywhere + .balign 16 + .globl tr_gdt +tr_gdt: + .short tr_gdt_end - tr_gdt - 1 # gdt limit + .long pa_tr_gdt + .short 0 + .quad 0x00cf9b000000ffff # __KERNEL32_CS + .quad 0x00af9b000000ffff # __KERNEL_CS + .quad 0x00cf93000000ffff # __KERNEL_DS +tr_gdt_end: +#endif + .balign 4 tr_idt: .fill 1, 6, 0 @@ -8,12 +23,16 @@ tr_idt: .fill 1, 6, 0 .balign 4 GLOBAL(trampoline_status) .space 4 + .balign 8 GLOBAL(trampoline_header) #ifdef CONFIG_X86_32 tr_start: .space 4 + tr_gdt_pad: .space 2 tr_gdt: .space 6 #else tr_start: .space 8 + GLOBAL(tr_cr4) .space 4 + GLOBAL(tr_efer) .space 8 #endif END(trampoline_header) |