arch/x86/kernel/cpu/intel.c

   1 #include <linux/init.h>
   2 #include <linux/kernel.h>
   3
   4 #include <linux/string.h>
   5 #include <linux/bitops.h>
   6 #include <linux/smp.h>
   7 #include <linux/thread_info.h>
   8 #include <linux/module.h>
   9
  10 #include <asm/processor.h>
  11 #include <asm/pgtable.h>
  12 #include <asm/msr.h>
  13 #include <asm/uaccess.h>
  14 #include <asm/ds.h>
  15 #include <asm/bugs.h>
  16 #include <asm/cpu.h>
  17
  18 #ifdef CONFIG_X86_64
  19 #include <asm/topology.h>
  20 #include <asm/numa_64.h>
  21 #endif
  22
  23 #include "cpu.h"
  24
  25 #ifdef CONFIG_X86_LOCAL_APIC
  26 #include <asm/mpspec.h>
  27 #include <asm/apic.h>
  28 #endif
  29
  30 static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
  31 {
  32         /* Unmask CPUID levels if masked: */
  33         if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
  34                 u64 misc_enable;
  35
  36                 rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
  37
  38                 if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) {
  39                         misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;
  40                         wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
  41                         c->cpuid_level = cpuid_eax(0);
  42                 }
  43         }
  44
  45         if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
  46                 (c->x86 == 0x6 && c->x86_model >= 0x0e))
  47                 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
  48
  49 #ifdef CONFIG_X86_64
  50         set_cpu_cap(c, X86_FEATURE_SYSENTER32);
  51 #else
  52         /* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
  53         if (c->x86 == 15 && c->x86_cache_alignment == 64)
  54                 c->x86_cache_alignment = 128;
  55 #endif
  56
  57         /*
  58          * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
  59          * with P/T states and does not stop in deep C-states
  60          */
  61         if (c->x86_power & (1 << 8)) {
  62                 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
  63                 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
  64         }
  65
  66         /*
  67          * There is a known erratum on Pentium III and Core Solo
  68          * and Core Duo CPUs.
  69          * " Page with PAT set to WC while associated MTRR is UC
  70          *   may consolidate to UC "
  71          * Because of this erratum, it is better to stick with
  72          * setting WC in MTRR rather than using PAT on these CPUs.
  73          *
  74          * Enable PAT WC only on P4, Core 2 or later CPUs.
  75          */
  76         if (c->x86 == 6 && c->x86_model < 15)
  77                 clear_cpu_cap(c, X86_FEATURE_PAT);
  78 }
  79
  80 #ifdef CONFIG_X86_32
  81 /*
  82  *      Early probe support logic for ppro memory erratum #50
  83  *
  84  *      This is called before we do cpu ident work
  85  */
  86
  87 int __cpuinit ppro_with_ram_bug(void)
  88 {
  89         /* Uses data from early_cpu_detect now */
  90         if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
  91             boot_cpu_data.x86 == 6 &&
  92             boot_cpu_data.x86_model == 1 &&
  93             boot_cpu_data.x86_mask < 8) {
  94                 printk(KERN_INFO "Pentium Pro with Errata#50 detected. Taking evasive action.\n");
  95                 return 1;
  96         }
  97         return 0;
  98 }
  99
 100 #ifdef CONFIG_X86_F00F_BUG
 101 static void __cpuinit trap_init_f00f_bug(void)
 102 {
 103         __set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);
 104
 105         /*
 106          * Update the IDT descriptor and reload the IDT so that
 107          * it uses the read-only mapped virtual address.
 108          */
 109         idt_descr.address = fix_to_virt(FIX_F00F_IDT);
 110         load_idt(&idt_descr);
 111 }
 112 #endif
 113
 114 static void __cpuinit intel_smp_check(struct cpuinfo_x86 *c)
 115 {
 116 #ifdef CONFIG_SMP
 117         /* calling is from identify_secondary_cpu() ? */
 118         if (c->cpu_index == boot_cpu_id)
 119                 return;
 120
 121         /*
 122          * Mask B, Pentium, but not Pentium MMX
 123          */
 124         if (c->x86 == 5 &&
 125             c->x86_mask >= 1 && c->x86_mask <= 4 &&
 126             c->x86_model <= 3) {
 127                 /*
 128                  * Remember we have B step Pentia with bugs
 129                  */
 130                 WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
 131                                     "with B stepping processors.\n");
 132         }
 133 #endif
 134 }
 135
 136 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 137 {
 138         unsigned long lo, hi;
 139
 140 #ifdef CONFIG_X86_F00F_BUG
 141         /*
 142          * All current models of Pentium and Pentium with MMX technology CPUs
 143          * have the F0 0F bug, which lets nonprivileged users lock up the system.
 144          * Note that the workaround only should be initialized once...
 145          */
 146         c->f00f_bug = 0;
 147         if (!paravirt_enabled() && c->x86 == 5) {
 148                 static int f00f_workaround_enabled;
 149
 150                 c->f00f_bug = 1;
 151                 if (!f00f_workaround_enabled) {
 152                         trap_init_f00f_bug();
 153                         printk(KERN_NOTICE "Intel Pentium with F0 0F bug - workaround enabled.\n");
 154                         f00f_workaround_enabled = 1;
 155                 }
 156         }
 157 #endif
 158
 159         /*
 160          * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
 161          * model 3 mask 3
 162          */
 163         if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
 164                 clear_cpu_cap(c, X86_FEATURE_SEP);
 165
 166         /*
 167          * P4 Xeon errata 037 workaround.
 168          * Hardware prefetcher may cause stale data to be loaded into the cache.
 169          */
 170         if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) {
 171                 rdmsr(MSR_IA32_MISC_ENABLE, lo, hi);
 172                 if ((lo & MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE) == 0) {
 173                         printk (KERN_INFO "CPU: C0 stepping P4 Xeon detected.\n");
 174                         printk (KERN_INFO "CPU: Disabling hardware prefetching (Errata 037)\n");
 175                         lo |= MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE;
 176                         wrmsr (MSR_IA32_MISC_ENABLE, lo, hi);
 177                 }
 178         }
 179
 180         /*
 181          * See if we have a good local APIC by checking for buggy Pentia,
 182          * i.e. all B steppings and the C2 stepping of P54C when using their
 183          * integrated APIC (see 11AP erratum in "Pentium Processor
 184          * Specification Update").
 185          */
 186         if (cpu_has_apic && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
 187             (c->x86_mask < 0x6 || c->x86_mask == 0xb))
 188                 set_cpu_cap(c, X86_FEATURE_11AP);
 189
 190
 191 #ifdef CONFIG_X86_INTEL_USERCOPY
 192         /*
 193          * Set up the preferred alignment for movsl bulk memory moves
 194          */
 195         switch (c->x86) {
 196         case 4:         /* 486: untested */
 197                 break;
 198         case 5:         /* Old Pentia: untested */
 199                 break;
 200         case 6:         /* PII/PIII only like movsl with 8-byte alignment */
 201                 movsl_mask.mask = 7;
 202                 break;
 203         case 15:        /* P4 is OK down to 8-byte alignment */
 204                 movsl_mask.mask = 7;
 205                 break;
 206         }
 207 #endif
 208
 209 #ifdef CONFIG_X86_NUMAQ
 210         numaq_tsc_disable();
 211 #endif
 212
 213         intel_smp_check(c);
 214 }
 215 #else
 216 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 217 {
 218 }
 219 #endif
 220
 221 static void __cpuinit srat_detect_node(void)
 222 {
 223 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
 224         unsigned node;
 225         int cpu = smp_processor_id();
 226         int apicid = hard_smp_processor_id();
 227
 228         /* Don't do the funky fallback heuristics the AMD version employs
 229            for now. */
 230         node = apicid_to_node[apicid];
 231         if (node == NUMA_NO_NODE || !node_online(node))
 232                 node = first_node(node_online_map);
 233         numa_set_node(cpu, node);
 234
 235         printk(KERN_INFO "CPU %d/0x%x -> Node %d\n", cpu, apicid, node);
 236 #endif
 237 }
 238
 239 /*
 240  * find out the number of processor cores on the die
 241  */
 242 static int __cpuinit intel_num_cpu_cores(struct cpuinfo_x86 *c)
 243 {
 244         unsigned int eax, ebx, ecx, edx;
 245
 246         if (c->cpuid_level < 4)
 247                 return 1;
 248
 249         /* Intel has a non-standard dependency on %ecx for this CPUID level. */
 250         cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
 251         if (eax & 0x1f)
 252                 return ((eax >> 26) + 1);
 253         else
 254                 return 1;
 255 }
 256
 257 static void __cpuinit detect_vmx_virtcap(struct cpuinfo_x86 *c)
 258 {
 259         /* Intel VMX MSR indicated features */
 260 #define X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW    0x00200000
 261 #define X86_VMX_FEATURE_PROC_CTLS_VNMI          0x00400000
 262 #define X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS      0x80000000
 263 #define X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC    0x00000001
 264 #define X86_VMX_FEATURE_PROC_CTLS2_EPT          0x00000002
 265 #define X86_VMX_FEATURE_PROC_CTLS2_VPID         0x00000020
 266
 267         u32 vmx_msr_low, vmx_msr_high, msr_ctl, msr_ctl2;
 268
 269         clear_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
 270         clear_cpu_cap(c, X86_FEATURE_VNMI);
 271         clear_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
 272         clear_cpu_cap(c, X86_FEATURE_EPT);
 273         clear_cpu_cap(c, X86_FEATURE_VPID);
 274
 275         rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, vmx_msr_low, vmx_msr_high);
 276         msr_ctl = vmx_msr_high | vmx_msr_low;
 277         if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW)
 278                 set_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
 279         if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_VNMI)
 280                 set_cpu_cap(c, X86_FEATURE_VNMI);
 281         if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS) {
 282                 rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
 283                       vmx_msr_low, vmx_msr_high);
 284                 msr_ctl2 = vmx_msr_high | vmx_msr_low;
 285                 if ((msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC) &&
 286                     (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW))
 287                         set_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
 288                 if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_EPT)
 289                         set_cpu_cap(c, X86_FEATURE_EPT);
 290                 if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VPID)
 291                         set_cpu_cap(c, X86_FEATURE_VPID);
 292         }
 293 }
 294
 295 static void __cpuinit init_intel(struct cpuinfo_x86 *c)
 296 {
 297         unsigned int l2 = 0;
 298
 299         early_init_intel(c);
 300
 301         intel_workarounds(c);
 302
 303         /*
 304          * Detect the extended topology information if available. This
 305          * will reinitialise the initial_apicid which will be used
 306          * in init_intel_cacheinfo()
 307          */
 308         detect_extended_topology(c);
 309
 310         l2 = init_intel_cacheinfo(c);
 311         if (c->cpuid_level > 9) {
 312                 unsigned eax = cpuid_eax(10);
 313                 /* Check for version and the number of counters */
 314                 if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
 315                         set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
 316         }
 317
 318         if (cpu_has_xmm2)
 319                 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
 320         if (cpu_has_ds) {
 321                 unsigned int l1;
 322                 rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
 323                 if (!(l1 & (1<<11)))
 324                         set_cpu_cap(c, X86_FEATURE_BTS);
 325                 if (!(l1 & (1<<12)))
 326                         set_cpu_cap(c, X86_FEATURE_PEBS);
 327                 ds_init_intel(c);
 328         }
 329
 330         if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush)
 331                 set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR);
 332
 333 #ifdef CONFIG_X86_64
 334         if (c->x86 == 15)
 335                 c->x86_cache_alignment = c->x86_clflush_size * 2;
 336         if (c->x86 == 6)
 337                 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 338 #else
 339         /*
 340          * Names for the Pentium II/Celeron processors
 341          * detectable only by also checking the cache size.
 342          * Dixon is NOT a Celeron.
 343          */
 344         if (c->x86 == 6) {
 345                 char *p = NULL;
 346
 347                 switch (c->x86_model) {
 348                 case 5:
 349                         if (c->x86_mask == 0) {
 350                                 if (l2 == 0)
 351                                         p = "Celeron (Covington)";
 352                                 else if (l2 == 256)
 353                                         p = "Mobile Pentium II (Dixon)";
 354                         }
 355                         break;
 356
 357                 case 6:
 358                         if (l2 == 128)
 359                                 p = "Celeron (Mendocino)";
 360                         else if (c->x86_mask == 0 || c->x86_mask == 5)
 361                                 p = "Celeron-A";
 362                         break;
 363
 364                 case 8:
 365                         if (l2 == 128)
 366                                 p = "Celeron (Coppermine)";
 367                         break;
 368                 }
 369
 370                 if (p)
 371                         strcpy(c->x86_model_id, p);
 372         }
 373
 374         if (c->x86 == 15)
 375                 set_cpu_cap(c, X86_FEATURE_P4);
 376         if (c->x86 == 6)
 377                 set_cpu_cap(c, X86_FEATURE_P3);
 378 #endif
 379
 380         if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
 381                 /*
 382                  * let's use the legacy cpuid vector 0x1 and 0x4 for topology
 383                  * detection.
 384                  */
 385                 c->x86_max_cores = intel_num_cpu_cores(c);
 386 #ifdef CONFIG_X86_32
 387                 detect_ht(c);
 388 #endif
 389         }
 390
 391         /* Work around errata */
 392         srat_detect_node();
 393
 394         if (cpu_has(c, X86_FEATURE_VMX))
 395                 detect_vmx_virtcap(c);
 396 }
 397
 398 #ifdef CONFIG_X86_32
 399 static unsigned int __cpuinit intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
 400 {
 401         /*
 402          * Intel PIII Tualatin. This comes in two flavours.
 403          * One has 256kb of cache, the other 512. We have no way
 404          * to determine which, so we use a boottime override
 405          * for the 512kb model, and assume 256 otherwise.
 406          */
 407         if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
 408                 size = 256;
 409         return size;
 410 }
 411 #endif
 412
 413 static const struct cpu_dev __cpuinitconst intel_cpu_dev = {
 414         .c_vendor       = "Intel",
 415         .c_ident        = { "GenuineIntel" },
 416 #ifdef CONFIG_X86_32
 417         .c_models = {
 418                 { .vendor = X86_VENDOR_INTEL, .family = 4, .model_names =
 419                   {
 420                           [0] = "486 DX-25/33",
 421                           [1] = "486 DX-50",
 422                           [2] = "486 SX",
 423                           [3] = "486 DX/2",
 424                           [4] = "486 SL",
 425                           [5] = "486 SX/2",
 426                           [7] = "486 DX/2-WB",
 427                           [8] = "486 DX/4",
 428                           [9] = "486 DX/4-WB"
 429                   }
 430                 },
 431                 { .vendor = X86_VENDOR_INTEL, .family = 5, .model_names =
 432                   {
 433                           [0] = "Pentium 60/66 A-step",
 434                           [1] = "Pentium 60/66",
 435                           [2] = "Pentium 75 - 200",
 436                           [3] = "OverDrive PODP5V83",
 437                           [4] = "Pentium MMX",
 438                           [7] = "Mobile Pentium 75 - 200",
 439                           [8] = "Mobile Pentium MMX"
 440                   }
 441                 },
 442                 { .vendor = X86_VENDOR_INTEL, .family = 6, .model_names =
 443                   {
 444                           [0] = "Pentium Pro A-step",
 445                           [1] = "Pentium Pro",
 446                           [3] = "Pentium II (Klamath)",
 447                           [4] = "Pentium II (Deschutes)",
 448                           [5] = "Pentium II (Deschutes)",
 449                           [6] = "Mobile Pentium II",
 450                           [7] = "Pentium III (Katmai)",
 451                           [8] = "Pentium III (Coppermine)",
 452                           [10] = "Pentium III (Cascades)",
 453                           [11] = "Pentium III (Tualatin)",
 454                   }
 455                 },
 456                 { .vendor = X86_VENDOR_INTEL, .family = 15, .model_names =
 457                   {
 458                           [0] = "Pentium 4 (Unknown)",
 459                           [1] = "Pentium 4 (Willamette)",
 460                           [2] = "Pentium 4 (Northwood)",
 461                           [4] = "Pentium 4 (Foster)",
 462                           [5] = "Pentium 4 (Foster)",
 463                   }
 464                 },
 465         },
 466         .c_size_cache   = intel_size_cache,
 467 #endif
 468         .c_early_init   = early_init_intel,
 469         .c_init         = init_intel,
 470         .c_x86_vendor   = X86_VENDOR_INTEL,
 471 };
 472
 473 cpu_dev_register(intel_cpu_dev);
 474