1 #include <linux/init.h>
2 #include <linux/kernel.h>
4 #include <linux/string.h>
5 #include <linux/bitops.h>
7 #include <linux/sched.h>
8 #include <linux/thread_info.h>
9 #include <linux/module.h>
10 #include <linux/uaccess.h>
12 #include <asm/processor.h>
13 #include <asm/pgtable.h>
19 #include <linux/topology.h>
20 #include <asm/numa_64.h>
25 #ifdef CONFIG_X86_LOCAL_APIC
26 #include <asm/mpspec.h>
30 static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
34 /* Unmask CPUID levels if masked: */
35 if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
36 rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
38 if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) {
40 misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;
41 wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
42 c->cpuid_level = cpuid_eax(0);
45 pr_warning("CPUID levels are restricted -"
46 " update hypervisor\n");
51 if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
52 (c->x86 == 0x6 && c->x86_model >= 0x0e))
53 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
56 if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64)) {
59 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
60 /* Required by the SDM */
62 rdmsr(MSR_IA32_UCODE_REV, lower_word, c->microcode);
66 * Atom erratum AAE44/AAF40/AAG38/AAH41:
68 * A race condition between speculative fetches and invalidating
69 * a large page. This is worked around in microcode, but we
70 * need the microcode to have already been loaded... so if it is
71 * not, recommend a BIOS update and disable large pages.
73 if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2 &&
74 c->microcode < 0x20e) {
75 printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n");
76 clear_cpu_cap(c, X86_FEATURE_PSE);
81 set_cpu_cap(c, X86_FEATURE_SYSENTER32);
83 /* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
84 if (c->x86 == 15 && c->x86_cache_alignment == 64)
85 c->x86_cache_alignment = 128;
88 /* CPUID workaround for 0F33/0F34 CPU */
89 if (c->x86 == 0xF && c->x86_model == 0x3
90 && (c->x86_mask == 0x3 || c->x86_mask == 0x4))
91 c->x86_phys_bits = 36;
94 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
95 * with P/T states and does not stop in deep C-states.
97 * It is also reliable across cores and sockets. (but not across
98 * cabinets - we turn it off in that case explicitly.)
100 if (c->x86_power & (1 << 8)) {
101 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
102 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
104 if (!check_tsc_unstable())
105 sched_clock_stable = 1;
110 * There is a known erratum on Pentium III and Core Solo
112 * " Page with PAT set to WC while associated MTRR is UC
113 * may consolidate to UC "
114 * Because of this erratum, it is better to stick with
115 * setting WC in MTRR rather than using PAT on these CPUs.
117 * Enable PAT WC only on P4, Core 2 or later CPUs.
119 if (c->x86 == 6 && c->x86_model < 15)
120 clear_cpu_cap(c, X86_FEATURE_PAT);
122 #ifdef CONFIG_KMEMCHECK
124 * P4s have a "fast strings" feature which causes single-
125 * stepping REP instructions to only generate a #DB on
126 * cache-line boundaries.
128 * Ingo Molnar reported a Pentium D (model 6) and a Xeon
129 * (model 2) with the same problem.
132 rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
134 if (misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING) {
135 printk(KERN_INFO "kmemcheck: Disabling fast string operations\n");
137 misc_enable &= ~MSR_IA32_MISC_ENABLE_FAST_STRING;
138 wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
144 * If fast string is not enabled in IA32_MISC_ENABLE for any reason,
145 * clear the fast string and enhanced fast string CPU capabilities.
147 if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
148 rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
149 if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
150 printk(KERN_INFO "Disabled fast string operations\n");
151 setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
152 setup_clear_cpu_cap(X86_FEATURE_ERMS);
159 * Early probe support logic for ppro memory erratum #50
161 * This is called before we do cpu ident work
164 int __cpuinit ppro_with_ram_bug(void)
166 /* Uses data from early_cpu_detect now */
167 if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
168 boot_cpu_data.x86 == 6 &&
169 boot_cpu_data.x86_model == 1 &&
170 boot_cpu_data.x86_mask < 8) {
171 printk(KERN_INFO "Pentium Pro with Errata#50 detected. Taking evasive action.\n");
177 #ifdef CONFIG_X86_F00F_BUG
178 static void __cpuinit trap_init_f00f_bug(void)
180 __set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);
183 * Update the IDT descriptor and reload the IDT so that
184 * it uses the read-only mapped virtual address.
186 idt_descr.address = fix_to_virt(FIX_F00F_IDT);
187 load_idt(&idt_descr);
191 static void __cpuinit intel_smp_check(struct cpuinfo_x86 *c)
193 /* calling is from identify_secondary_cpu() ? */
198 * Mask B, Pentium, but not Pentium MMX
201 c->x86_mask >= 1 && c->x86_mask <= 4 &&
204 * Remember we have B step Pentia with bugs
206 WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
207 "with B stepping processors.\n");
211 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
213 unsigned long lo, hi;
215 #ifdef CONFIG_X86_F00F_BUG
217 * All current models of Pentium and Pentium with MMX technology CPUs
218 * have the F0 0F bug, which lets nonprivileged users lock up the
220 * Note that the workaround only should be initialized once...
223 if (!paravirt_enabled() && c->x86 == 5) {
224 static int f00f_workaround_enabled;
227 if (!f00f_workaround_enabled) {
228 trap_init_f00f_bug();
229 printk(KERN_NOTICE "Intel Pentium with F0 0F bug - workaround enabled.\n");
230 f00f_workaround_enabled = 1;
236 * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
239 if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
240 clear_cpu_cap(c, X86_FEATURE_SEP);
243 * P4 Xeon errata 037 workaround.
244 * Hardware prefetcher may cause stale data to be loaded into the cache.
246 if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) {
247 rdmsr(MSR_IA32_MISC_ENABLE, lo, hi);
248 if ((lo & MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE) == 0) {
249 printk (KERN_INFO "CPU: C0 stepping P4 Xeon detected.\n");
251 printk (KERN_INFO "CPU: Disabling hardware prefetching (Errata 037)\n");
252 lo |= MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE;
253 wrmsr(MSR_IA32_MISC_ENABLE, lo, hi);
255 pr_warning("CPU: Hypervisor update needed\n");
261 * See if we have a good local APIC by checking for buggy Pentia,
262 * i.e. all B steppings and the C2 stepping of P54C when using their
263 * integrated APIC (see 11AP erratum in "Pentium Processor
264 * Specification Update").
266 if (cpu_has_apic && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
267 (c->x86_mask < 0x6 || c->x86_mask == 0xb))
268 set_cpu_cap(c, X86_FEATURE_11AP);
271 #ifdef CONFIG_X86_INTEL_USERCOPY
273 * Set up the preferred alignment for movsl bulk memory moves
276 case 4: /* 486: untested */
278 case 5: /* Old Pentia: untested */
280 case 6: /* PII/PIII only like movsl with 8-byte alignment */
283 case 15: /* P4 is OK down to 8-byte alignment */
289 #ifdef CONFIG_X86_NUMAQ
296 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
302 static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
306 int cpu = smp_processor_id();
308 /* Don't do the funky fallback heuristics the AMD version employs
310 node = numa_cpu_node(cpu);
311 if (node == NUMA_NO_NODE || !node_online(node)) {
312 /* reuse the value from init_cpu_to_node() */
313 node = cpu_to_node(cpu);
315 numa_set_node(cpu, node);
320 * find out the number of processor cores on the die
322 static int __cpuinit intel_num_cpu_cores(struct cpuinfo_x86 *c)
324 unsigned int eax, ebx, ecx, edx;
326 if (c->cpuid_level < 4)
329 /* Intel has a non-standard dependency on %ecx for this CPUID level. */
330 cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
332 return (eax >> 26) + 1;
337 static void __cpuinit detect_vmx_virtcap(struct cpuinfo_x86 *c)
339 /* Intel VMX MSR indicated features */
340 #define X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW 0x00200000
341 #define X86_VMX_FEATURE_PROC_CTLS_VNMI 0x00400000
342 #define X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS 0x80000000
343 #define X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC 0x00000001
344 #define X86_VMX_FEATURE_PROC_CTLS2_EPT 0x00000002
345 #define X86_VMX_FEATURE_PROC_CTLS2_VPID 0x00000020
347 u32 vmx_msr_low, vmx_msr_high, msr_ctl, msr_ctl2;
349 clear_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
350 clear_cpu_cap(c, X86_FEATURE_VNMI);
351 clear_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
352 clear_cpu_cap(c, X86_FEATURE_EPT);
353 clear_cpu_cap(c, X86_FEATURE_VPID);
355 rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, vmx_msr_low, vmx_msr_high);
356 msr_ctl = vmx_msr_high | vmx_msr_low;
357 if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW)
358 set_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
359 if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_VNMI)
360 set_cpu_cap(c, X86_FEATURE_VNMI);
361 if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS) {
362 rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
363 vmx_msr_low, vmx_msr_high);
364 msr_ctl2 = vmx_msr_high | vmx_msr_low;
365 if ((msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC) &&
366 (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW))
367 set_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
368 if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_EPT)
369 set_cpu_cap(c, X86_FEATURE_EPT);
370 if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VPID)
371 set_cpu_cap(c, X86_FEATURE_VPID);
376 static void __cpuinit init_intel(struct cpuinfo_x86 *c)
382 intel_workarounds(c);
385 * Detect the extended topology information if available. This
386 * will reinitialise the initial_apicid which will be used
387 * in init_intel_cacheinfo()
389 detect_extended_topology(c);
391 l2 = init_intel_cacheinfo(c);
392 if (c->cpuid_level > 9) {
393 unsigned eax = cpuid_eax(10);
394 /* Check for version and the number of counters */
395 if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
396 set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
400 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
403 rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
405 set_cpu_cap(c, X86_FEATURE_BTS);
407 set_cpu_cap(c, X86_FEATURE_PEBS);
410 if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush)
411 set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR);
415 c->x86_cache_alignment = c->x86_clflush_size * 2;
417 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
420 * Names for the Pentium II/Celeron processors
421 * detectable only by also checking the cache size.
422 * Dixon is NOT a Celeron.
427 switch (c->x86_model) {
430 p = "Celeron (Covington)";
432 p = "Mobile Pentium II (Dixon)";
437 p = "Celeron (Mendocino)";
438 else if (c->x86_mask == 0 || c->x86_mask == 5)
444 p = "Celeron (Coppermine)";
449 strcpy(c->x86_model_id, p);
453 set_cpu_cap(c, X86_FEATURE_P4);
455 set_cpu_cap(c, X86_FEATURE_P3);
459 if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
461 * let's use the legacy cpuid vector 0x1 and 0x4 for topology
464 c->x86_max_cores = intel_num_cpu_cores(c);
470 /* Work around errata */
473 if (cpu_has(c, X86_FEATURE_VMX))
474 detect_vmx_virtcap(c);
478 * Initialize MSR_IA32_ENERGY_PERF_BIAS if BIOS did not.
479 * x86_energy_perf_policy(8) is available to change it at run-time
481 if (cpu_has(c, X86_FEATURE_EPB)) {
484 rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
485 if ((epb & 0xF) == ENERGY_PERF_BIAS_PERFORMANCE) {
486 printk_once(KERN_WARNING "ENERGY_PERF_BIAS:"
487 " Set to 'normal', was 'performance'\n"
488 "ENERGY_PERF_BIAS: View and update with"
489 " x86_energy_perf_policy(8)\n");
490 epb = (epb & ~0xF) | ENERGY_PERF_BIAS_NORMAL;
491 wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
497 static unsigned int __cpuinit intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
500 * Intel PIII Tualatin. This comes in two flavours.
501 * One has 256kb of cache, the other 512. We have no way
502 * to determine which, so we use a boottime override
503 * for the 512kb model, and assume 256 otherwise.
505 if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
511 static const struct cpu_dev __cpuinitconst intel_cpu_dev = {
513 .c_ident = { "GenuineIntel" },
516 { .vendor = X86_VENDOR_INTEL, .family = 4, .model_names =
518 [0] = "486 DX-25/33",
529 { .vendor = X86_VENDOR_INTEL, .family = 5, .model_names =
531 [0] = "Pentium 60/66 A-step",
532 [1] = "Pentium 60/66",
533 [2] = "Pentium 75 - 200",
534 [3] = "OverDrive PODP5V83",
536 [7] = "Mobile Pentium 75 - 200",
537 [8] = "Mobile Pentium MMX"
540 { .vendor = X86_VENDOR_INTEL, .family = 6, .model_names =
542 [0] = "Pentium Pro A-step",
544 [3] = "Pentium II (Klamath)",
545 [4] = "Pentium II (Deschutes)",
546 [5] = "Pentium II (Deschutes)",
547 [6] = "Mobile Pentium II",
548 [7] = "Pentium III (Katmai)",
549 [8] = "Pentium III (Coppermine)",
550 [10] = "Pentium III (Cascades)",
551 [11] = "Pentium III (Tualatin)",
554 { .vendor = X86_VENDOR_INTEL, .family = 15, .model_names =
556 [0] = "Pentium 4 (Unknown)",
557 [1] = "Pentium 4 (Willamette)",
558 [2] = "Pentium 4 (Northwood)",
559 [4] = "Pentium 4 (Foster)",
560 [5] = "Pentium 4 (Foster)",
564 .c_size_cache = intel_size_cache,
566 .c_early_init = early_init_intel,
567 .c_init = init_intel,
568 .c_x86_vendor = X86_VENDOR_INTEL,
571 cpu_dev_register(intel_cpu_dev);