-/*
- * include/asm-i386/bugs.h
- *
- * Copyright (C) 1994 Linus Torvalds
- *
- * Cyrix stuff, June 1998 by:
- * - Rafael R. Reilova (moved everything from head.S),
- * <rreilova@ececs.uc.edu>
- * - Channing Corn (tests & fixes),
- * - Andrew D. Balsa (code cleanup).
- */
-
/*
* This is included by init/main.c to check for architecture-dependent bugs.
*
* Needs:
* void check_bugs(void);
*/
+#ifndef _ASM_I386_BUG_H
+#define _ASM_I386_BUG_H
-#include <linux/init.h>
-#include <asm/processor.h>
-#include <asm/i387.h>
-#include <asm/msr.h>
-#include <asm/paravirt.h>
-
-static int __init no_halt(char *s)
-{
- boot_cpu_data.hlt_works_ok = 0;
- return 1;
-}
-
-__setup("no-hlt", no_halt);
-
-static int __init mca_pentium(char *s)
-{
- mca_pentium_flag = 1;
- return 1;
-}
-
-__setup("mca-pentium", mca_pentium);
-
-static int __init no_387(char *s)
-{
- boot_cpu_data.hard_math = 0;
- write_cr0(0xE | read_cr0());
- return 1;
-}
-
-__setup("no387", no_387);
-
-static double __initdata x = 4195835.0;
-static double __initdata y = 3145727.0;
-
-/*
- * This used to check for exceptions..
- * However, it turns out that to support that,
- * the XMM trap handlers basically had to
- * be buggy. So let's have a correct XMM trap
- * handler, and forget about printing out
- * some status at boot.
- *
- * We should really only care about bugs here
- * anyway. Not features.
- */
-static void __init check_fpu(void)
-{
- if (!boot_cpu_data.hard_math) {
-#ifndef CONFIG_MATH_EMULATION
- printk(KERN_EMERG "No coprocessor found and no math emulation present.\n");
- printk(KERN_EMERG "Giving up.\n");
- for (;;) ;
-#endif
- return;
- }
-
-/* trap_init() enabled FXSR and company _before_ testing for FP problems here. */
- /* Test for the divl bug.. */
- __asm__("fninit\n\t"
- "fldl %1\n\t"
- "fdivl %2\n\t"
- "fmull %2\n\t"
- "fldl %1\n\t"
- "fsubp %%st,%%st(1)\n\t"
- "fistpl %0\n\t"
- "fwait\n\t"
- "fninit"
- : "=m" (*&boot_cpu_data.fdiv_bug)
- : "m" (*&x), "m" (*&y));
- if (boot_cpu_data.fdiv_bug)
- printk("Hmm, FPU with FDIV bug.\n");
-}
-
-static void __init check_hlt(void)
-{
- if (paravirt_enabled())
- return;
-
- printk(KERN_INFO "Checking 'hlt' instruction... ");
- if (!boot_cpu_data.hlt_works_ok) {
- printk("disabled\n");
- return;
- }
- halt();
- halt();
- halt();
- halt();
- printk("OK.\n");
-}
-
-/*
- * Most 386 processors have a bug where a POPAD can lock the
- * machine even from user space.
- */
-
-static void __init check_popad(void)
-{
-#ifndef CONFIG_X86_POPAD_OK
- int res, inp = (int) &res;
-
- printk(KERN_INFO "Checking for popad bug... ");
- __asm__ __volatile__(
- "movl $12345678,%%eax; movl $0,%%edi; pusha; popa; movl (%%edx,%%edi),%%ecx "
- : "=&a" (res)
- : "d" (inp)
- : "ecx", "edi" );
- /* If this fails, it means that any user program may lock the CPU hard. Too bad. */
- if (res != 12345678) printk( "Buggy.\n" );
- else printk( "OK.\n" );
-#endif
-}
-
-/*
- * Check whether we are able to run this kernel safely on SMP.
- *
- * - In order to run on a i386, we need to be compiled for i386
- * (for due to lack of "invlpg" and working WP on a i386)
- * - In order to run on anything without a TSC, we need to be
- * compiled for a i486.
- * - In order to support the local APIC on a buggy Pentium machine,
- * we need to be compiled with CONFIG_X86_GOOD_APIC disabled,
- * which happens implicitly if compiled for a Pentium or lower
- * (unless an advanced selection of CPU features is used) as an
- * otherwise config implies a properly working local APIC without
- * the need to do extra reads from the APIC.
-*/
-
-static void __init check_config(void)
-{
-/*
- * We'd better not be a i386 if we're configured to use some
- * i486+ only features! (WP works in supervisor mode and the
- * new "invlpg" and "bswap" instructions)
- */
-#if defined(CONFIG_X86_WP_WORKS_OK) || defined(CONFIG_X86_INVLPG) || defined(CONFIG_X86_BSWAP)
- if (boot_cpu_data.x86 == 3)
- panic("Kernel requires i486+ for 'invlpg' and other features");
-#endif
-
-/*
- * If we configured ourselves for a TSC, we'd better have one!
- */
-#ifdef CONFIG_X86_TSC
- if (!cpu_has_tsc)
- panic("Kernel compiled for Pentium+, requires TSC feature!");
-#endif
-
-/*
- * If we were told we had a good local APIC, check for buggy Pentia,
- * i.e. all B steppings and the C2 stepping of P54C when using their
- * integrated APIC (see 11AP erratum in "Pentium Processor
- * Specification Update").
- */
-#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_GOOD_APIC)
- if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL
- && cpu_has_apic
- && boot_cpu_data.x86 == 5
- && boot_cpu_data.x86_model == 2
- && (boot_cpu_data.x86_mask < 6 || boot_cpu_data.x86_mask == 11))
- panic("Kernel compiled for PMMX+, assumes a local APIC without the read-before-write bug!");
-#endif
-}
-
-extern void alternative_instructions(void);
+void check_bugs(void);
-static void __init check_bugs(void)
-{
- identify_cpu(&boot_cpu_data);
-#ifndef CONFIG_SMP
- printk("CPU: ");
- print_cpu_info(&boot_cpu_data);
-#endif
- check_config();
- check_fpu();
- check_hlt();
- check_popad();
- init_utsname()->machine[1] = '0' + (boot_cpu_data.x86 > 6 ? 6 : boot_cpu_data.x86);
- alternative_instructions();
-}
+#endif /* _ASM_I386_BUG_H */
git.samba.org / sfrench / cifs-2.6.git / blobdiff