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/sched.h>
   8 #include <linux/thread_info.h>
   9 #include <linux/module.h>
  10
  11 #include <asm/processor.h>
  12 #include <asm/pgtable.h>
  13 #include <asm/msr.h>
  14 #include <asm/uaccess.h>
  15 #include <asm/ds.h>
  16 #include <asm/bugs.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          * It is also reliable across cores and sockets. (but not across
  62          * cabinets - we turn it off in that case explicitly.)
  63          */
  64         if (c->x86_power & (1 << 8)) {
  65                 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
  66                 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
  67                 set_cpu_cap(c, X86_FEATURE_TSC_RELIABLE);
  68                 sched_clock_stable = 1;
  69         }
  70
  71         /*
  72          * There is a known erratum on Pentium III and Core Solo
  73          * and Core Duo CPUs.
  74          * " Page with PAT set to WC while associated MTRR is UC
  75          *   may consolidate to UC "
  76          * Because of this erratum, it is better to stick with
  77          * setting WC in MTRR rather than using PAT on these CPUs.
  78          *
  79          * Enable PAT WC only on P4, Core 2 or later CPUs.
  80          */
  81         if (c->x86 == 6 && c->x86_model < 15)
  82                 clear_cpu_cap(c, X86_FEATURE_PAT);
  83 }
  84
  85 #ifdef CONFIG_X86_32
  86 /*
  87  *      Early probe support logic for ppro memory erratum #50
  88  *
  89  *      This is called before we do cpu ident work
  90  */
  91
  92 int __cpuinit ppro_with_ram_bug(void)
  93 {
  94         /* Uses data from early_cpu_detect now */
  95         if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
  96             boot_cpu_data.x86 == 6 &&
  97             boot_cpu_data.x86_model == 1 &&
  98             boot_cpu_data.x86_mask < 8) {
  99                 printk(KERN_INFO "Pentium Pro with Errata#50 detected. Taking evasive action.\n");
 100                 return 1;
 101         }
 102         return 0;
 103 }
 104
 105 #ifdef CONFIG_X86_F00F_BUG
 106 static void __cpuinit trap_init_f00f_bug(void)
 107 {
 108         __set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);
 109
 110         /*
 111          * Update the IDT descriptor and reload the IDT so that
 112          * it uses the read-only mapped virtual address.
 113          */
 114         idt_descr.address = fix_to_virt(FIX_F00F_IDT);
 115         load_idt(&idt_descr);
 116 }
 117 #endif
 118
 119 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 120 {
 121         unsigned long lo, hi;
 122
 123 #ifdef CONFIG_X86_F00F_BUG
 124         /*
 125          * All current models of Pentium and Pentium with MMX technology CPUs
 126          * have the F0 0F bug, which lets nonprivileged users lock up the system.
 127          * Note that the workaround only should be initialized once...
 128          */
 129         c->f00f_bug = 0;
 130         if (!paravirt_enabled() && c->x86 == 5) {
 131                 static int f00f_workaround_enabled;
 132
 133                 c->f00f_bug = 1;
 134                 if (!f00f_workaround_enabled) {
 135                         trap_init_f00f_bug();
 136                         printk(KERN_NOTICE "Intel Pentium with F0 0F bug - workaround enabled.\n");
 137                         f00f_workaround_enabled = 1;
 138                 }
 139         }
 140 #endif
 141
 142         /*
 143          * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
 144          * model 3 mask 3
 145          */
 146         if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
 147                 clear_cpu_cap(c, X86_FEATURE_SEP);
 148
 149         /*
 150          * P4 Xeon errata 037 workaround.
 151          * Hardware prefetcher may cause stale data to be loaded into the cache.
 152          */
 153         if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) {
 154                 rdmsr(MSR_IA32_MISC_ENABLE, lo, hi);
 155                 if ((lo & MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE) == 0) {
 156                         printk (KERN_INFO "CPU: C0 stepping P4 Xeon detected.\n");
 157                         printk (KERN_INFO "CPU: Disabling hardware prefetching (Errata 037)\n");
 158                         lo |= MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE;
 159                         wrmsr (MSR_IA32_MISC_ENABLE, lo, hi);
 160                 }
 161         }
 162
 163         /*
 164          * See if we have a good local APIC by checking for buggy Pentia,
 165          * i.e. all B steppings and the C2 stepping of P54C when using their
 166          * integrated APIC (see 11AP erratum in "Pentium Processor
 167          * Specification Update").
 168          */
 169         if (cpu_has_apic && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
 170             (c->x86_mask < 0x6 || c->x86_mask == 0xb))
 171                 set_cpu_cap(c, X86_FEATURE_11AP);
 172
 173
 174 #ifdef CONFIG_X86_INTEL_USERCOPY
 175         /*
 176          * Set up the preferred alignment for movsl bulk memory moves
 177          */
 178         switch (c->x86) {
 179         case 4:         /* 486: untested */
 180                 break;
 181         case 5:         /* Old Pentia: untested */
 182                 break;
 183         case 6:         /* PII/PIII only like movsl with 8-byte alignment */
 184                 movsl_mask.mask = 7;
 185                 break;
 186         case 15:        /* P4 is OK down to 8-byte alignment */
 187                 movsl_mask.mask = 7;
 188                 break;
 189         }
 190 #endif
 191
 192 #ifdef CONFIG_X86_NUMAQ
 193         numaq_tsc_disable();
 194 #endif
 195 }
 196 #else
 197 static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 198 {
 199 }
 200 #endif
 201
 202 static void __cpuinit srat_detect_node(void)
 203 {
 204 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
 205         unsigned node;
 206         int cpu = smp_processor_id();
 207         int apicid = hard_smp_processor_id();
 208
 209         /* Don't do the funky fallback heuristics the AMD version employs
 210            for now. */
 211         node = apicid_to_node[apicid];
 212         if (node == NUMA_NO_NODE || !node_online(node))
 213                 node = first_node(node_online_map);
 214         numa_set_node(cpu, node);
 215
 216         printk(KERN_INFO "CPU %d/0x%x -> Node %d\n", cpu, apicid, node);
 217 #endif
 218 }
 219
 220 /*
 221  * find out the number of processor cores on the die
 222  */
 223 static int __cpuinit intel_num_cpu_cores(struct cpuinfo_x86 *c)
 224 {
 225         unsigned int eax, ebx, ecx, edx;
 226
 227         if (c->cpuid_level < 4)
 228                 return 1;
 229
 230         /* Intel has a non-standard dependency on %ecx for this CPUID level. */
 231         cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
 232         if (eax & 0x1f)
 233                 return ((eax >> 26) + 1);
 234         else
 235                 return 1;
 236 }
 237
 238 static void __cpuinit detect_vmx_virtcap(struct cpuinfo_x86 *c)
 239 {
 240         /* Intel VMX MSR indicated features */
 241 #define X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW    0x00200000
 242 #define X86_VMX_FEATURE_PROC_CTLS_VNMI          0x00400000
 243 #define X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS      0x80000000
 244 #define X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC    0x00000001
 245 #define X86_VMX_FEATURE_PROC_CTLS2_EPT          0x00000002
 246 #define X86_VMX_FEATURE_PROC_CTLS2_VPID         0x00000020
 247
 248         u32 vmx_msr_low, vmx_msr_high, msr_ctl, msr_ctl2;
 249
 250         clear_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
 251         clear_cpu_cap(c, X86_FEATURE_VNMI);
 252         clear_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
 253         clear_cpu_cap(c, X86_FEATURE_EPT);
 254         clear_cpu_cap(c, X86_FEATURE_VPID);
 255
 256         rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, vmx_msr_low, vmx_msr_high);
 257         msr_ctl = vmx_msr_high | vmx_msr_low;
 258         if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW)
 259                 set_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
 260         if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_VNMI)
 261                 set_cpu_cap(c, X86_FEATURE_VNMI);
 262         if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS) {
 263                 rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
 264                       vmx_msr_low, vmx_msr_high);
 265                 msr_ctl2 = vmx_msr_high | vmx_msr_low;
 266                 if ((msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC) &&
 267                     (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW))
 268                         set_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
 269                 if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_EPT)
 270                         set_cpu_cap(c, X86_FEATURE_EPT);
 271                 if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VPID)
 272                         set_cpu_cap(c, X86_FEATURE_VPID);
 273         }
 274 }
 275
 276 static void __cpuinit init_intel(struct cpuinfo_x86 *c)
 277 {
 278         unsigned int l2 = 0;
 279
 280         early_init_intel(c);
 281
 282         intel_workarounds(c);
 283
 284         /*
 285          * Detect the extended topology information if available. This
 286          * will reinitialise the initial_apicid which will be used
 287          * in init_intel_cacheinfo()
 288          */
 289         detect_extended_topology(c);
 290
 291         l2 = init_intel_cacheinfo(c);
 292         if (c->cpuid_level > 9) {
 293                 unsigned eax = cpuid_eax(10);
 294                 /* Check for version and the number of counters */
 295                 if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
 296                         set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
 297         }
 298
 299         if (cpu_has_xmm2)
 300                 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
 301         if (cpu_has_ds) {
 302                 unsigned int l1;
 303                 rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
 304                 if (!(l1 & (1<<11)))
 305                         set_cpu_cap(c, X86_FEATURE_BTS);
 306                 if (!(l1 & (1<<12)))
 307                         set_cpu_cap(c, X86_FEATURE_PEBS);
 308                 ds_init_intel(c);
 309         }
 310
 311         if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush)
 312                 set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR);
 313
 314 #ifdef CONFIG_X86_64
 315         if (c->x86 == 15)
 316                 c->x86_cache_alignment = c->x86_clflush_size * 2;
 317         if (c->x86 == 6)
 318                 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 319 #else
 320         /*
 321          * Names for the Pentium II/Celeron processors
 322          * detectable only by also checking the cache size.
 323          * Dixon is NOT a Celeron.
 324          */
 325         if (c->x86 == 6) {
 326                 char *p = NULL;
 327
 328                 switch (c->x86_model) {
 329                 case 5:
 330                         if (c->x86_mask == 0) {
 331                                 if (l2 == 0)
 332                                         p = "Celeron (Covington)";
 333                                 else if (l2 == 256)
 334                                         p = "Mobile Pentium II (Dixon)";
 335                         }
 336                         break;
 337
 338                 case 6:
 339                         if (l2 == 128)
 340                                 p = "Celeron (Mendocino)";
 341                         else if (c->x86_mask == 0 || c->x86_mask == 5)
 342                                 p = "Celeron-A";
 343                         break;
 344
 345                 case 8:
 346                         if (l2 == 128)
 347                                 p = "Celeron (Coppermine)";
 348                         break;
 349                 }
 350
 351                 if (p)
 352                         strcpy(c->x86_model_id, p);
 353         }
 354
 355         if (c->x86 == 15)
 356                 set_cpu_cap(c, X86_FEATURE_P4);
 357         if (c->x86 == 6)
 358                 set_cpu_cap(c, X86_FEATURE_P3);
 359 #endif
 360
 361         if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
 362                 /*
 363                  * let's use the legacy cpuid vector 0x1 and 0x4 for topology
 364                  * detection.
 365                  */
 366                 c->x86_max_cores = intel_num_cpu_cores(c);
 367 #ifdef CONFIG_X86_32
 368                 detect_ht(c);
 369 #endif
 370         }
 371
 372         /* Work around errata */
 373         srat_detect_node();
 374
 375         if (cpu_has(c, X86_FEATURE_VMX))
 376                 detect_vmx_virtcap(c);
 377 }
 378
 379 #ifdef CONFIG_X86_32
 380 static unsigned int __cpuinit intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
 381 {
 382         /*
 383          * Intel PIII Tualatin. This comes in two flavours.
 384          * One has 256kb of cache, the other 512. We have no way
 385          * to determine which, so we use a boottime override
 386          * for the 512kb model, and assume 256 otherwise.
 387          */
 388         if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
 389                 size = 256;
 390         return size;
 391 }
 392 #endif
 393
 394 static struct cpu_dev intel_cpu_dev __cpuinitdata = {
 395         .c_vendor       = "Intel",
 396         .c_ident        = { "GenuineIntel" },
 397 #ifdef CONFIG_X86_32
 398         .c_models = {
 399                 { .vendor = X86_VENDOR_INTEL, .family = 4, .model_names =
 400                   {
 401                           [0] = "486 DX-25/33",
 402                           [1] = "486 DX-50",
 403                           [2] = "486 SX",
 404                           [3] = "486 DX/2",
 405                           [4] = "486 SL",
 406                           [5] = "486 SX/2",
 407                           [7] = "486 DX/2-WB",
 408                           [8] = "486 DX/4",
 409                           [9] = "486 DX/4-WB"
 410                   }
 411                 },
 412                 { .vendor = X86_VENDOR_INTEL, .family = 5, .model_names =
 413                   {
 414                           [0] = "Pentium 60/66 A-step",
 415                           [1] = "Pentium 60/66",
 416                           [2] = "Pentium 75 - 200",
 417                           [3] = "OverDrive PODP5V83",
 418                           [4] = "Pentium MMX",
 419                           [7] = "Mobile Pentium 75 - 200",
 420                           [8] = "Mobile Pentium MMX"
 421                   }
 422                 },
 423                 { .vendor = X86_VENDOR_INTEL, .family = 6, .model_names =
 424                   {
 425                           [0] = "Pentium Pro A-step",
 426                           [1] = "Pentium Pro",
 427                           [3] = "Pentium II (Klamath)",
 428                           [4] = "Pentium II (Deschutes)",
 429                           [5] = "Pentium II (Deschutes)",
 430                           [6] = "Mobile Pentium II",
 431                           [7] = "Pentium III (Katmai)",
 432                           [8] = "Pentium III (Coppermine)",
 433                           [10] = "Pentium III (Cascades)",
 434                           [11] = "Pentium III (Tualatin)",
 435                   }
 436                 },
 437                 { .vendor = X86_VENDOR_INTEL, .family = 15, .model_names =
 438                   {
 439                           [0] = "Pentium 4 (Unknown)",
 440                           [1] = "Pentium 4 (Willamette)",
 441                           [2] = "Pentium 4 (Northwood)",
 442                           [4] = "Pentium 4 (Foster)",
 443                           [5] = "Pentium 4 (Foster)",
 444                   }
 445                 },
 446         },
 447         .c_size_cache   = intel_size_cache,
 448 #endif
 449         .c_early_init   = early_init_intel,
 450         .c_init         = init_intel,
 451         .c_x86_vendor   = X86_VENDOR_INTEL,
 452 };
 453
 454 cpu_dev_register(intel_cpu_dev);
 455