diff options
| -rw-r--r-- | arch/x86_64/boot/compressed/head.S | 19 | ||||
| -rw-r--r-- | arch/x86_64/boot/setup.S | 65 | ||||
| -rw-r--r-- | arch/x86_64/kernel/acpi/wakeup.S | 30 | ||||
| -rw-r--r-- | arch/x86_64/kernel/trampoline.S | 51 | ||||
| -rw-r--r-- | arch/x86_64/kernel/verify_cpu.S | 110 |
5 files changed, 152 insertions, 123 deletions
diff --git a/arch/x86_64/boot/compressed/head.S b/arch/x86_64/boot/compressed/head.S index c353a92..f9d5692 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 deb3573..816d04f 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 diff --git a/arch/x86_64/kernel/acpi/wakeup.S b/arch/x86_64/kernel/acpi/wakeup.S index 766cfbc..8550a6f 100644 --- a/arch/x86_64/kernel/acpi/wakeup.S +++ b/arch/x86_64/kernel/acpi/wakeup.S @@ -43,6 +43,11 @@ wakeup_code: cmpl $0x12345678, %eax jne bogus_real_magic + call verify_cpu # Verify the cpu supports long + # mode + testl %eax, %eax + jnz no_longmode + testl $1, video_flags - wakeup_code jz 1f lcall $0xc000,$3 @@ -92,18 +97,6 @@ wakeup_32: # Running in this code, but at low address; paging is not yet turned on. movb $0xa5, %al ; outb %al, $0x80 - /* Check if extended functions are implemented */ - movl $0x80000000, %eax - cpuid - cmpl $0x80000000, %eax - jbe bogus_cpu - wbinvd - mov $0x80000001, %eax - cpuid - btl $29, %edx - jnc bogus_cpu - movl %edx,%edi - movl $__KERNEL_DS, %eax movl %eax, %ds @@ -123,6 +116,11 @@ wakeup_32: leal (wakeup_level4_pgt - wakeup_code)(%esi), %eax movl %eax, %cr3 + /* Check if nx is implemented */ + movl $0x80000001, %eax + cpuid + movl %edx,%edi + /* Enable Long Mode */ xorl %eax, %eax btsl $_EFER_LME, %eax @@ -244,10 +242,12 @@ bogus_64_magic: movb $0xb3,%al ; outb %al,$0x80 jmp bogus_64_magic -bogus_cpu: - movb $0xbc,%al ; outb %al,$0x80 - jmp bogus_cpu +.code16 +no_longmode: + movb $0xbc,%al ; outb %al,$0x80 + jmp no_longmode +#include "../verify_cpu.S" /* This code uses an extended set of video mode numbers. These include: * Aliases for standard modes diff --git a/arch/x86_64/kernel/trampoline.S b/arch/x86_64/kernel/trampoline.S index 13eee63..e7e2764 100644 --- a/arch/x86_64/kernel/trampoline.S +++ b/arch/x86_64/kernel/trampoline.S @@ -54,6 +54,8 @@ r_base = . 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 @@ -121,57 +123,10 @@ startup_64: jmp *%rax .code16 -verify_cpu: - pushl $0 # Kill any dangerous flags - popfl - - /* minimum CPUID flags for x86-64 */ - /* see http://www.x86-64.org/lists/discuss/msg02971.html */ -#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\ - (1<<13)|(1<<15)|(1<<24)|(1<<25)|(1<<26)) -#define REQUIRED_MASK2 (1<<29) - - pushfl # check for cpuid - popl %eax - movl %eax, %ebx - xorl $0x200000,%eax - pushl %eax - popfl - pushfl - popl %eax - pushl %ebx - popfl - cmpl %eax, %ebx - jz no_longmode - - xorl %eax, %eax # See if cpuid 1 is implemented - cpuid - cmpl $0x1, %eax - jb no_longmode - - movl $0x01, %eax # Does the cpu have what it takes? - cpuid - andl $REQUIRED_MASK1, %edx - xorl $REQUIRED_MASK1, %edx - jnz no_longmode - - movl $0x80000000, %eax # See if extended cpuid is implemented - cpuid - cmpl $0x80000001, %eax - jb no_longmode - - movl $0x80000001, %eax # Does the cpu have what it takes? - cpuid - andl $REQUIRED_MASK2, %edx - xorl $REQUIRED_MASK2, %edx - jnz no_longmode - - ret # The cpu supports long mode - no_longmode: hlt jmp no_longmode - +#include "verify_cpu.S" # Careful these need to be in the same 64K segment as the above; tidt: diff --git a/arch/x86_64/kernel/verify_cpu.S b/arch/x86_64/kernel/verify_cpu.S new file mode 100644 index 0000000..72edabd --- /dev/null +++ b/arch/x86_64/kernel/verify_cpu.S @@ -0,0 +1,110 @@ +/* + * + * verify_cpu.S - Code for cpu long mode and SSE verification. This + * code has been borrowed from boot/setup.S and was introduced by + * Andi Kleen. + * + * Copyright (c) 2007 Andi Kleen (ak@suse.de) + * Copyright (c) 2007 Eric Biederman (ebiederm@xmission.com) + * Copyright (c) 2007 Vivek Goyal (vgoyal@in.ibm.com) + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + * + * This is a common code for verification whether CPU supports + * long mode and SSE or not. It is not called directly instead this + * file is included at various places and compiled in that context. + * Following are the current usage. + * + * This file is included by both 16bit and 32bit code. + * + * arch/x86_64/boot/setup.S : Boot cpu verification (16bit) + * arch/x86_64/boot/compressed/head.S: Boot cpu verification (32bit) + * arch/x86_64/kernel/trampoline.S: secondary processor verfication (16bit) + * arch/x86_64/kernel/acpi/wakeup.S:Verfication at resume (16bit) + * + * verify_cpu, returns the status of cpu check in register %eax. + * 0: Success 1: Failure + * + * The caller needs to check for the error code and take the action + * appropriately. Either display a message or halt. + */ + +verify_cpu: + + pushfl # Save caller passed flags + pushl $0 # Kill any dangerous flags + popfl + + /* 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 verify_cpu_no_longmode # cpu has no cpuid + + movl $0x0,%eax # See if cpuid 1 is implemented + cpuid + cmpl $0x1,%eax + jb verify_cpu_no_longmode # no cpuid 1 + + xor %di,%di + cmpl $0x68747541,%ebx # AuthenticAMD + jnz verify_cpu_noamd + cmpl $0x69746e65,%edx + jnz verify_cpu_noamd + cmpl $0x444d4163,%ecx + jnz verify_cpu_noamd + mov $1,%di # cpu is from AMD + +verify_cpu_noamd: + movl $0x1,%eax # Does the cpu have what it takes + cpuid + andl $REQUIRED_MASK1,%edx + xorl $REQUIRED_MASK1,%edx + jnz verify_cpu_no_longmode + + movl $0x80000000,%eax # See if extended cpuid is implemented + cpuid + cmpl $0x80000001,%eax + jb verify_cpu_no_longmode # no extended cpuid + + movl $0x80000001,%eax # Does the cpu have what it takes + cpuid + andl $REQUIRED_MASK2,%edx + xorl $REQUIRED_MASK2,%edx + jnz verify_cpu_no_longmode + +verify_cpu_sse_test: + movl $1,%eax + cpuid + andl $SSE_MASK,%edx + cmpl $SSE_MASK,%edx + je verify_cpu_sse_ok + test %di,%di + jz verify_cpu_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 verify_cpu_sse_test # try again + +verify_cpu_no_longmode: + popfl # Restore caller passed flags + movl $1,%eax + ret +verify_cpu_sse_ok: + popfl # Restore caller passed flags + xorl %eax, %eax + ret |