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-rw-r--r--arch/i386/boot/cpucheck.c268
1 files changed, 0 insertions, 268 deletions
diff --git a/arch/i386/boot/cpucheck.c b/arch/i386/boot/cpucheck.c
deleted file mode 100644
index e655a89c551..00000000000
--- a/arch/i386/boot/cpucheck.c
+++ /dev/null
@@ -1,268 +0,0 @@
-/* -*- linux-c -*- ------------------------------------------------------- *
- *
- * Copyright (C) 1991, 1992 Linus Torvalds
- * Copyright 2007 rPath, Inc. - All Rights Reserved
- *
- * This file is part of the Linux kernel, and is made available under
- * the terms of the GNU General Public License version 2.
- *
- * ----------------------------------------------------------------------- */
-
-/*
- * arch/i386/boot/cpucheck.c
- *
- * Check for obligatory CPU features and abort if the features are not
- * present. This code should be compilable as 16-, 32- or 64-bit
- * code, so be very careful with types and inline assembly.
- *
- * This code should not contain any messages; that requires an
- * additional wrapper.
- *
- * As written, this code is not safe for inclusion into the kernel
- * proper (after FPU initialization, in particular).
- */
-
-#ifdef _SETUP
-# include "boot.h"
-# include "bitops.h"
-#endif
-#include <linux/types.h>
-#include <asm/cpufeature.h>
-#include <asm/processor-flags.h>
-#include <asm/required-features.h>
-#include <asm/msr-index.h>
-
-struct cpu_features {
- int level; /* Family, or 64 for x86-64 */
- int model;
- u32 flags[NCAPINTS];
-};
-
-static struct cpu_features cpu;
-static u32 cpu_vendor[3];
-static u32 err_flags[NCAPINTS];
-
-#ifdef CONFIG_X86_64
-static const int req_level = 64;
-#elif defined(CONFIG_X86_MINIMUM_CPU_FAMILY)
-static const int req_level = CONFIG_X86_MINIMUM_CPU_FAMILY;
-#else
-static const int req_level = 3;
-#endif
-
-static const u32 req_flags[NCAPINTS] =
-{
- REQUIRED_MASK0,
- REQUIRED_MASK1,
- REQUIRED_MASK2,
- REQUIRED_MASK3,
- REQUIRED_MASK4,
- REQUIRED_MASK5,
- REQUIRED_MASK6,
- REQUIRED_MASK7,
-};
-
-#define A32(a,b,c,d) (((d) << 24)+((c) << 16)+((b) << 8)+(a))
-
-static int is_amd(void)
-{
- return cpu_vendor[0] == A32('A','u','t','h') &&
- cpu_vendor[1] == A32('e','n','t','i') &&
- cpu_vendor[2] == A32('c','A','M','D');
-}
-
-static int is_centaur(void)
-{
- return cpu_vendor[0] == A32('C','e','n','t') &&
- cpu_vendor[1] == A32('a','u','r','H') &&
- cpu_vendor[2] == A32('a','u','l','s');
-}
-
-static int is_transmeta(void)
-{
- return cpu_vendor[0] == A32('G','e','n','u') &&
- cpu_vendor[1] == A32('i','n','e','T') &&
- cpu_vendor[2] == A32('M','x','8','6');
-}
-
-static int has_fpu(void)
-{
- u16 fcw = -1, fsw = -1;
- u32 cr0;
-
- asm("movl %%cr0,%0" : "=r" (cr0));
- if (cr0 & (X86_CR0_EM|X86_CR0_TS)) {
- cr0 &= ~(X86_CR0_EM|X86_CR0_TS);
- asm volatile("movl %0,%%cr0" : : "r" (cr0));
- }
-
- asm volatile("fninit ; fnstsw %0 ; fnstcw %1"
- : "+m" (fsw), "+m" (fcw));
-
- return fsw == 0 && (fcw & 0x103f) == 0x003f;
-}
-
-static int has_eflag(u32 mask)
-{
- u32 f0, f1;
-
- asm("pushfl ; "
- "pushfl ; "
- "popl %0 ; "
- "movl %0,%1 ; "
- "xorl %2,%1 ; "
- "pushl %1 ; "
- "popfl ; "
- "pushfl ; "
- "popl %1 ; "
- "popfl"
- : "=&r" (f0), "=&r" (f1)
- : "ri" (mask));
-
- return !!((f0^f1) & mask);
-}
-
-static void get_flags(void)
-{
- u32 max_intel_level, max_amd_level;
- u32 tfms;
-
- if (has_fpu())
- set_bit(X86_FEATURE_FPU, cpu.flags);
-
- if (has_eflag(X86_EFLAGS_ID)) {
- asm("cpuid"
- : "=a" (max_intel_level),
- "=b" (cpu_vendor[0]),
- "=d" (cpu_vendor[1]),
- "=c" (cpu_vendor[2])
- : "a" (0));
-
- if (max_intel_level >= 0x00000001 &&
- max_intel_level <= 0x0000ffff) {
- asm("cpuid"
- : "=a" (tfms),
- "=c" (cpu.flags[4]),
- "=d" (cpu.flags[0])
- : "a" (0x00000001)
- : "ebx");
- cpu.level = (tfms >> 8) & 15;
- cpu.model = (tfms >> 4) & 15;
- if (cpu.level >= 6)
- cpu.model += ((tfms >> 16) & 0xf) << 4;
- }
-
- asm("cpuid"
- : "=a" (max_amd_level)
- : "a" (0x80000000)
- : "ebx", "ecx", "edx");
-
- if (max_amd_level >= 0x80000001 &&
- max_amd_level <= 0x8000ffff) {
- u32 eax = 0x80000001;
- asm("cpuid"
- : "+a" (eax),
- "=c" (cpu.flags[6]),
- "=d" (cpu.flags[1])
- : : "ebx");
- }
- }
-}
-
-/* Returns a bitmask of which words we have error bits in */
-static int check_flags(void)
-{
- u32 err;
- int i;
-
- err = 0;
- for (i = 0; i < NCAPINTS; i++) {
- err_flags[i] = req_flags[i] & ~cpu.flags[i];
- if (err_flags[i])
- err |= 1 << i;
- }
-
- return err;
-}
-
-/*
- * Returns -1 on error.
- *
- * *cpu_level is set to the current CPU level; *req_level to the required
- * level. x86-64 is considered level 64 for this purpose.
- *
- * *err_flags_ptr is set to the flags error array if there are flags missing.
- */
-int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr)
-{
- int err;
-
- memset(&cpu.flags, 0, sizeof cpu.flags);
- cpu.level = 3;
-
- if (has_eflag(X86_EFLAGS_AC))
- cpu.level = 4;
-
- get_flags();
- err = check_flags();
-
- if (test_bit(X86_FEATURE_LM, cpu.flags))
- cpu.level = 64;
-
- if (err == 0x01 &&
- !(err_flags[0] &
- ~((1 << X86_FEATURE_XMM)|(1 << X86_FEATURE_XMM2))) &&
- is_amd()) {
- /* If this is an AMD and we're only missing SSE+SSE2, try to
- turn them on */
-
- u32 ecx = MSR_K7_HWCR;
- u32 eax, edx;
-
- asm("rdmsr" : "=a" (eax), "=d" (edx) : "c" (ecx));
- eax &= ~(1 << 15);
- asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
-
- get_flags(); /* Make sure it really did something */
- err = check_flags();
- } else if (err == 0x01 &&
- !(err_flags[0] & ~(1 << X86_FEATURE_CX8)) &&
- is_centaur() && cpu.model >= 6) {
- /* If this is a VIA C3, we might have to enable CX8
- explicitly */
-
- u32 ecx = MSR_VIA_FCR;
- u32 eax, edx;
-
- asm("rdmsr" : "=a" (eax), "=d" (edx) : "c" (ecx));
- eax |= (1<<1)|(1<<7);
- asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
-
- set_bit(X86_FEATURE_CX8, cpu.flags);
- err = check_flags();
- } else if (err == 0x01 && is_transmeta()) {
- /* Transmeta might have masked feature bits in word 0 */
-
- u32 ecx = 0x80860004;
- u32 eax, edx;
- u32 level = 1;
-
- asm("rdmsr" : "=a" (eax), "=d" (edx) : "c" (ecx));
- asm("wrmsr" : : "a" (~0), "d" (edx), "c" (ecx));
- asm("cpuid"
- : "+a" (level), "=d" (cpu.flags[0])
- : : "ecx", "ebx");
- asm("wrmsr" : : "a" (eax), "d" (edx), "c" (ecx));
-
- err = check_flags();
- }
-
- if (err_flags_ptr)
- *err_flags_ptr = err ? err_flags : NULL;
- if (cpu_level_ptr)
- *cpu_level_ptr = cpu.level;
- if (req_level_ptr)
- *req_level_ptr = req_level;
-
- return (cpu.level < req_level || err) ? -1 : 0;
-}
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