From a4831e08b7f3ed51623c9eb25e8c945b76b3eda3 Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Wed, 2 May 2007 19:27:08 +0200 Subject: [PATCH] x86-64: Move cpu verification code to common file o This patch moves the code to verify long mode and SSE to a common file. This code is now shared by trampoline.S, wakeup.S, boot/setup.S and boot/compressed/head.S o So far we used to do very limited check in trampoline.S, wakeup.S and in 32bit entry point. Now all the entry paths are forced to do the exhaustive check, including SSE because verify_cpu is shared. o I am keeping this patch as last in the x86 relocatable series because previous patches have got quite some amount of testing done and don't want to distrub that. So that if there is problem introduced by this patch, at least it can be easily isolated. Signed-off-by: Eric W. Biederman Signed-off-by: Vivek Goyal Signed-off-by: Andi Kleen --- arch/x86_64/boot/compressed/head.S | 19 ++++++++++- arch/x86_64/boot/setup.S | 65 ++++---------------------------------- 2 files changed, 24 insertions(+), 60 deletions(-) (limited to 'arch/x86_64/boot') diff --git a/arch/x86_64/boot/compressed/head.S b/arch/x86_64/boot/compressed/head.S index c353a9266ea..f9d5692a010 100644 --- a/arch/x86_64/boot/compressed/head.S +++ b/arch/x86_64/boot/compressed/head.S @@ -54,6 +54,15 @@ startup_32: 1: popl %ebp subl $1b, %ebp +/* setup a stack and make sure cpu supports long mode. */ + movl $user_stack_end, %eax + addl %ebp, %eax + movl %eax, %esp + + call verify_cpu + testl %eax, %eax + jnz no_longmode + /* Compute the delta between where we were compiled to run at * and where the code will actually run at. */ @@ -159,13 +168,21 @@ startup_32: /* Jump from 32bit compatibility mode into 64bit mode. */ lret +no_longmode: + /* This isn't an x86-64 CPU so hang */ +1: + hlt + jmp 1b + +#include "../../kernel/verify_cpu.S" + /* Be careful here startup_64 needs to be at a predictable * address so I can export it in an ELF header. Bootloaders * should look at the ELF header to find this address, as * it may change in the future. */ .code64 - .org 0x100 + .org 0x200 ENTRY(startup_64) /* We come here either from startup_32 or directly from a * 64bit bootloader. If we come here from a bootloader we depend on diff --git a/arch/x86_64/boot/setup.S b/arch/x86_64/boot/setup.S index deb3573c7ae..816d04faa2b 100644 --- a/arch/x86_64/boot/setup.S +++ b/arch/x86_64/boot/setup.S @@ -299,64 +299,10 @@ loader_ok: movw %cs,%ax movw %ax,%ds - /* minimum CPUID flags for x86-64 */ - /* see http://www.x86-64.org/lists/discuss/msg02971.html */ -#define SSE_MASK ((1<<25)|(1<<26)) -#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\ - (1<<13)|(1<<15)|(1<<24)) -#define REQUIRED_MASK2 (1<<29) - - pushfl /* standard way to check for cpuid */ - popl %eax - movl %eax,%ebx - xorl $0x200000,%eax - pushl %eax - popfl - pushfl - popl %eax - cmpl %eax,%ebx - jz no_longmode /* cpu has no cpuid */ - movl $0x0,%eax - cpuid - cmpl $0x1,%eax - jb no_longmode /* no cpuid 1 */ - xor %di,%di - cmpl $0x68747541,%ebx /* AuthenticAMD */ - jnz noamd - cmpl $0x69746e65,%edx - jnz noamd - cmpl $0x444d4163,%ecx - jnz noamd - mov $1,%di /* cpu is from AMD */ -noamd: - movl $0x1,%eax - cpuid - andl $REQUIRED_MASK1,%edx - xorl $REQUIRED_MASK1,%edx - jnz no_longmode - movl $0x80000000,%eax - cpuid - cmpl $0x80000001,%eax - jb no_longmode /* no extended cpuid */ - movl $0x80000001,%eax - cpuid - andl $REQUIRED_MASK2,%edx - xorl $REQUIRED_MASK2,%edx - jnz no_longmode -sse_test: - movl $1,%eax - cpuid - andl $SSE_MASK,%edx - cmpl $SSE_MASK,%edx - je sse_ok - test %di,%di - jz no_longmode /* only try to force SSE on AMD */ - movl $0xc0010015,%ecx /* HWCR */ - rdmsr - btr $15,%eax /* enable SSE */ - wrmsr - xor %di,%di /* don't loop */ - jmp sse_test /* try again */ + call verify_cpu + testl %eax,%eax + jz sse_ok + no_longmode: call beep lea long_mode_panic,%si @@ -366,7 +312,8 @@ no_longmode_loop: long_mode_panic: .string "Your CPU does not support long mode. Use a 32bit distribution." .byte 0 - + +#include "../kernel/verify_cpu.S" sse_ok: popw %ds -- cgit v1.2.3-70-g09d2