diff options
| author | H. Peter Anvin <hpa@linux.intel.com> | 2011-02-14 15:34:57 -0800 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2011-02-17 21:02:43 -0800 |
| commit | 4822b7fc6d4870685a9feadfc348d48f5e47460a (patch) | |
| tree | 52a482fde76ff8bae64fc09761967a33b9b7b08b /arch/x86/kernel/trampoline_64.S | |
| parent | 85e2efbb1db9a18d218006706d6e4fbeb0216213 (diff) | |
x86, trampoline: Common infrastructure for low memory trampolines
Common infrastructure for low memory trampolines. This code installs
the trampolines permanently in low memory very early. It also permits
multiple pieces of code to be used for this purpose.
This code also introduces a standard infrastructure for computing
symbol addresses in the trampoline code.
The only change to the actual SMP trampolines themselves is that the
64-bit trampoline has been made reusable -- the previous version would
overwrite the code with a status variable; this moves the status
variable to a separate location.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
LKML-Reference: <4D5DFBE4.7090104@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Matthieu Castet <castet.matthieu@free.fr>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Diffstat (limited to 'arch/x86/kernel/trampoline_64.S')
| -rw-r--r-- | arch/x86/kernel/trampoline_64.S | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/arch/x86/kernel/trampoline_64.S b/arch/x86/kernel/trampoline_64.S index 075d130efcf..49c77a68252 100644 --- a/arch/x86/kernel/trampoline_64.S +++ b/arch/x86/kernel/trampoline_64.S @@ -32,13 +32,9 @@ #include <asm/segment.h> #include <asm/processor-flags.h> -#ifdef CONFIG_ACPI_SLEEP -.section .rodata, "a", @progbits -#else -/* We can free up the trampoline after bootup if cpu hotplug is not supported. */ -__CPUINITRODATA -#endif -.code16 + .section ".x86_trampoline","a" + .balign PAGE_SIZE + .code16 ENTRY(trampoline_data) r_base = . @@ -50,7 +46,7 @@ r_base = . mov %ax, %ss - movl $0xA5A5A5A5, trampoline_data - r_base + movl $0xA5A5A5A5, trampoline_status - r_base # write marker for master knows we're running # Setup stack @@ -64,10 +60,13 @@ r_base = . 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 + # Fixup the absolute vectors + leal (startup_32 - r_base)(%esi), %eax + movl %eax, startup_32_vector - r_base + leal (startup_64 - r_base)(%esi), %eax + movl %eax, startup_64_vector - r_base + leal (tgdt - r_base)(%esi), %eax + movl %eax, (tgdt + 2 - r_base) /* * GDT tables in non default location kernel can be beyond 16MB and @@ -129,6 +128,7 @@ no_longmode: jmp no_longmode #include "verify_cpu.S" + .balign 4 # Careful these need to be in the same 64K segment as the above; tidt: .word 0 # idt limit = 0 @@ -156,6 +156,12 @@ startup_64_vector: .long startup_64 - r_base .word __KERNEL_CS, 0 + .balign 4 +fixup_base: + .long 0 +ENTRY(trampoline_status) + .long 0 + trampoline_stack: .org 0x1000 trampoline_stack_end: |