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x86: intel.c put workaround for old cpus together
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consolidate the code some more.

No change in functionality intended.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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Yinghai Lu authored and Ingo Molnar committed Sep 10, 2008
1 parent 879d792 commit 4052704
Showing 1 changed file with 98 additions and 94 deletions.
192 changes: 98 additions & 94 deletions arch/x86/kernel/cpu/intel.c
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Original file line number Diff line number Diff line change
Expand Up @@ -63,15 +63,54 @@ int __cpuinit ppro_with_ram_bug(void)
return 0;
}

#ifdef CONFIG_X86_F00F_BUG
static void __cpuinit trap_init_f00f_bug(void)
{
__set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);

/*
* P4 Xeon errata 037 workaround.
* Hardware prefetcher may cause stale data to be loaded into the cache.
*/
static void __cpuinit Intel_errata_workarounds(struct cpuinfo_x86 *c)
/*
* Update the IDT descriptor and reload the IDT so that
* it uses the read-only mapped virtual address.
*/
idt_descr.address = fix_to_virt(FIX_F00F_IDT);
load_idt(&idt_descr);
}
#endif

static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
{
unsigned long lo, hi;

#ifdef CONFIG_X86_F00F_BUG
/*
* All current models of Pentium and Pentium with MMX technology CPUs
* have the F0 0F bug, which lets nonprivileged users lock up the system.
* Note that the workaround only should be initialized once...
*/
c->f00f_bug = 0;
if (!paravirt_enabled() && c->x86 == 5) {
static int f00f_workaround_enabled;

c->f00f_bug = 1;
if (!f00f_workaround_enabled) {
trap_init_f00f_bug();
printk(KERN_NOTICE "Intel Pentium with F0 0F bug - workaround enabled.\n");
f00f_workaround_enabled = 1;
}
}
#endif

/*
* SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
* model 3 mask 3
*/
if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
clear_cpu_cap(c, X86_FEATURE_SEP);

/*
* P4 Xeon errata 037 workaround.
* Hardware prefetcher may cause stale data to be loaded into the cache.
*/
if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) {
rdmsr(MSR_IA32_MISC_ENABLE, lo, hi);
if ((lo & (1<<9)) == 0) {
Expand All @@ -81,23 +120,44 @@ static void __cpuinit Intel_errata_workarounds(struct cpuinfo_x86 *c)
wrmsr (MSR_IA32_MISC_ENABLE, lo, hi);
}
}
}


/*
* See if we have a good local APIC by checking 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 (cpu_has_apic && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
(c->x86_mask < 0x6 || c->x86_mask == 0xb))
set_cpu_cap(c, X86_FEATURE_11AP);

#ifdef CONFIG_X86_F00F_BUG
static void __cpuinit trap_init_f00f_bug(void)
{
__set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);

#ifdef CONFIG_X86_INTEL_USERCOPY
/*
* Update the IDT descriptor and reload the IDT so that
* it uses the read-only mapped virtual address.
* Set up the preferred alignment for movsl bulk memory moves
*/
idt_descr.address = fix_to_virt(FIX_F00F_IDT);
load_idt(&idt_descr);
}
switch (c->x86) {
case 4: /* 486: untested */
break;
case 5: /* Old Pentia: untested */
break;
case 6: /* PII/PIII only like movsl with 8-byte alignment */
movsl_mask.mask = 7;
break;
case 15: /* P4 is OK down to 8-byte alignment */
movsl_mask.mask = 7;
break;
}
#endif

#ifdef CONFIG_X86_NUMAQ
numaq_tsc_disable();
#endif
}
#else
static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
{
}
#endif

static void __cpuinit srat_detect_node(void)
Expand Down Expand Up @@ -139,28 +199,10 @@ static int __cpuinit intel_num_cpu_cores(struct cpuinfo_x86 *c)
static void __cpuinit init_intel(struct cpuinfo_x86 *c)
{
unsigned int l2 = 0;
char *p = NULL;

early_init_intel(c);

#ifdef CONFIG_X86_F00F_BUG
/*
* All current models of Pentium and Pentium with MMX technology CPUs
* have the F0 0F bug, which lets nonprivileged users lock up the system.
* Note that the workaround only should be initialized once...
*/
c->f00f_bug = 0;
if (!paravirt_enabled() && c->x86 == 5) {
static int f00f_workaround_enabled;

c->f00f_bug = 1;
if (!f00f_workaround_enabled) {
trap_init_f00f_bug();
printk(KERN_NOTICE "Intel Pentium with F0 0F bug - workaround enabled.\n");
f00f_workaround_enabled = 1;
}
}
#endif
intel_workarounds(c);

l2 = init_intel_cacheinfo(c);
if (c->cpuid_level > 9) {
Expand All @@ -170,17 +212,32 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
}

#ifdef CONFIG_X86_32
/* SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until model 3 mask 3 */
if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
clear_cpu_cap(c, X86_FEATURE_SEP);
if (cpu_has_xmm2)
set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
if (cpu_has_ds) {
unsigned int l1;
rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
if (!(l1 & (1<<11)))
set_cpu_cap(c, X86_FEATURE_BTS);
if (!(l1 & (1<<12)))
set_cpu_cap(c, X86_FEATURE_PEBS);
ds_init_intel(c);
}

#ifdef CONFIG_X86_64
if (c->x86 == 15)
c->x86_cache_alignment = c->x86_clflush_size * 2;
if (c->x86 == 6)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
#else
/*
* Names for the Pentium II/Celeron processors
* detectable only by also checking the cache size.
* Dixon is NOT a Celeron.
*/
if (c->x86 == 6) {
char *p = NULL;

switch (c->x86_model) {
case 5:
if (c->x86_mask == 0) {
Expand All @@ -203,51 +260,11 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
p = "Celeron (Coppermine)";
break;
}
}

if (p)
strcpy(c->x86_model_id, p);

Intel_errata_workarounds(c);

#ifdef CONFIG_X86_INTEL_USERCOPY
/*
* Set up the preferred alignment for movsl bulk memory moves
*/
switch (c->x86) {
case 4: /* 486: untested */
break;
case 5: /* Old Pentia: untested */
break;
case 6: /* PII/PIII only like movsl with 8-byte alignment */
movsl_mask.mask = 7;
break;
case 15: /* P4 is OK down to 8-byte alignment */
movsl_mask.mask = 7;
break;
if (p)
strcpy(c->x86_model_id, p);
}
#endif

#endif

if (cpu_has_xmm2)
set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
if (cpu_has_ds) {
unsigned int l1;
rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
if (!(l1 & (1<<11)))
set_cpu_cap(c, X86_FEATURE_BTS);
if (!(l1 & (1<<12)))
set_cpu_cap(c, X86_FEATURE_PEBS);
ds_init_intel(c);
}

#ifdef CONFIG_X86_64
if (c->x86 == 15)
c->x86_cache_alignment = c->x86_clflush_size * 2;
if (c->x86 == 6)
set_cpu_cap(c, X86_FEATURE_REP_GOOD);
#else
if (c->x86 == 15)
set_cpu_cap(c, X86_FEATURE_P4);
if (c->x86 == 6)
Expand All @@ -256,19 +273,6 @@ static void __cpuinit init_intel(struct cpuinfo_x86 *c)
if (cpu_has_bts)
ptrace_bts_init_intel(c);

/*
* See if we have a good local APIC by checking 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 (cpu_has_apic && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
(c->x86_mask < 0x6 || c->x86_mask == 0xb))
set_cpu_cap(c, X86_FEATURE_11AP);

#ifdef CONFIG_X86_NUMAQ
numaq_tsc_disable();
#endif
#endif

detect_extended_topology(c);
Expand Down

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