arch/x86/kernel/cpu/amd.c

   1 #include <linux/init.h>
   2 #include <linux/bitops.h>
   3 #include <linux/mm.h>
   4
   5 #include <asm/io.h>
   6 #include <asm/processor.h>
   7 #include <asm/apic.h>
   8 #include <asm/cpu.h>
   9
  10 #ifdef CONFIG_X86_64
  11 # include <asm/numa_64.h>
  12 # include <asm/mmconfig.h>
  13 # include <asm/cacheflush.h>
  14 #endif
  15
  16 #include "cpu.h"
  17
  18 #ifdef CONFIG_X86_32
  19 /*
  20  *      B step AMD K6 before B 9730xxxx have hardware bugs that can cause
  21  *      misexecution of code under Linux. Owners of such processors should
  22  *      contact AMD for precise details and a CPU swap.
  23  *
  24  *      See     http://www.multimania.com/poulot/k6bug.html
  25  *              http://www.amd.com/K6/k6docs/revgd.html
  26  *
  27  *      The following test is erm.. interesting. AMD neglected to up
  28  *      the chip setting when fixing the bug but they also tweaked some
  29  *      performance at the same time..
  30  */
  31
  32 extern void vide(void);
  33 __asm__(".align 4\nvide: ret");
  34
  35 static void __cpuinit init_amd_k5(struct cpuinfo_x86 *c)
  36 {
  37 /*
  38  * General Systems BIOSen alias the cpu frequency registers
  39  * of the Elan at 0x000df000. Unfortuantly, one of the Linux
  40  * drivers subsequently pokes it, and changes the CPU speed.
  41  * Workaround : Remove the unneeded alias.
  42  */
  43 #define CBAR            (0xfffc) /* Configuration Base Address  (32-bit) */
  44 #define CBAR_ENB        (0x80000000)
  45 #define CBAR_KEY        (0X000000CB)
  46         if (c->x86_model == 9 || c->x86_model == 10) {
  47                 if (inl (CBAR) & CBAR_ENB)
  48                         outl (0 | CBAR_KEY, CBAR);
  49         }
  50 }
  51
  52
  53 static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
  54 {
  55         u32 l, h;
  56         int mbytes = num_physpages >> (20-PAGE_SHIFT);
  57
  58         if (c->x86_model < 6) {
  59                 /* Based on AMD doc 20734R - June 2000 */
  60                 if (c->x86_model == 0) {
  61                         clear_cpu_cap(c, X86_FEATURE_APIC);
  62                         set_cpu_cap(c, X86_FEATURE_PGE);
  63                 }
  64                 return;
  65         }
  66
  67         if (c->x86_model == 6 && c->x86_mask == 1) {
  68                 const int K6_BUG_LOOP = 1000000;
  69                 int n;
  70                 void (*f_vide)(void);
  71                 unsigned long d, d2;
  72
  73                 printk(KERN_INFO "AMD K6 stepping B detected - ");
  74
  75                 /*
  76                  * It looks like AMD fixed the 2.6.2 bug and improved indirect
  77                  * calls at the same time.
  78                  */
  79
  80                 n = K6_BUG_LOOP;
  81                 f_vide = vide;
  82                 rdtscl(d);
  83                 while (n--)
  84                         f_vide();
  85                 rdtscl(d2);
  86                 d = d2-d;
  87
  88                 if (d > 20*K6_BUG_LOOP)
  89                         printk("system stability may be impaired when more than 32 MB are used.\n");
  90                 else
  91                         printk("probably OK (after B9730xxxx).\n");
  92                 printk(KERN_INFO "Please see http://membres.lycos.fr/poulot/k6bug.html\n");
  93         }
  94
  95         /* K6 with old style WHCR */
  96         if (c->x86_model < 8 ||
  97            (c->x86_model == 8 && c->x86_mask < 8)) {
  98                 /* We can only write allocate on the low 508Mb */
  99                 if (mbytes > 508)
 100                         mbytes = 508;
 101
 102                 rdmsr(MSR_K6_WHCR, l, h);
 103                 if ((l&0x0000FFFF) == 0) {
 104                         unsigned long flags;
 105                         l = (1<<0)|((mbytes/4)<<1);
 106                         local_irq_save(flags);
 107                         wbinvd();
 108                         wrmsr(MSR_K6_WHCR, l, h);
 109                         local_irq_restore(flags);
 110                         printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
 111                                 mbytes);
 112                 }
 113                 return;
 114         }
 115
 116         if ((c->x86_model == 8 && c->x86_mask > 7) ||
 117              c->x86_model == 9 || c->x86_model == 13) {
 118                 /* The more serious chips .. */
 119
 120                 if (mbytes > 4092)
 121                         mbytes = 4092;
 122
 123                 rdmsr(MSR_K6_WHCR, l, h);
 124                 if ((l&0xFFFF0000) == 0) {
 125                         unsigned long flags;
 126                         l = ((mbytes>>2)<<22)|(1<<16);
 127                         local_irq_save(flags);
 128                         wbinvd();
 129                         wrmsr(MSR_K6_WHCR, l, h);
 130                         local_irq_restore(flags);
 131                         printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
 132                                 mbytes);
 133                 }
 134
 135                 return;
 136         }
 137
 138         if (c->x86_model == 10) {
 139                 /* AMD Geode LX is model 10 */
 140                 /* placeholder for any needed mods */
 141                 return;
 142         }
 143 }
 144
 145 static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
 146 {
 147 #ifdef CONFIG_SMP
 148         /* calling is from identify_secondary_cpu() ? */
 149         if (c->cpu_index == boot_cpu_id)
 150                 return;
 151
 152         /*
 153          * Certain Athlons might work (for various values of 'work') in SMP
 154          * but they are not certified as MP capable.
 155          */
 156         /* Athlon 660/661 is valid. */
 157         if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
 158             (c->x86_mask == 1)))
 159                 goto valid_k7;
 160
 161         /* Duron 670 is valid */
 162         if ((c->x86_model == 7) && (c->x86_mask == 0))
 163                 goto valid_k7;
 164
 165         /*
 166          * Athlon 662, Duron 671, and Athlon >model 7 have capability
 167          * bit. It's worth noting that the A5 stepping (662) of some
 168          * Athlon XP's have the MP bit set.
 169          * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
 170          * more.
 171          */
 172         if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
 173             ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
 174              (c->x86_model > 7))
 175                 if (cpu_has_mp)
 176                         goto valid_k7;
 177
 178         /* If we get here, not a certified SMP capable AMD system. */
 179
 180         /*
 181          * Don't taint if we are running SMP kernel on a single non-MP
 182          * approved Athlon
 183          */
 184         WARN_ONCE(1, "WARNING: This combination of AMD"
 185                 "processors is not suitable for SMP.\n");
 186         if (!test_taint(TAINT_UNSAFE_SMP))
 187                 add_taint(TAINT_UNSAFE_SMP);
 188
 189 valid_k7:
 190         ;
 191 #endif
 192 }
 193
 194 static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
 195 {
 196         u32 l, h;
 197
 198         /*
 199          * Bit 15 of Athlon specific MSR 15, needs to be 0
 200          * to enable SSE on Palomino/Morgan/Barton CPU's.
 201          * If the BIOS didn't enable it already, enable it here.
 202          */
 203         if (c->x86_model >= 6 && c->x86_model <= 10) {
 204                 if (!cpu_has(c, X86_FEATURE_XMM)) {
 205                         printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
 206                         rdmsr(MSR_K7_HWCR, l, h);
 207                         l &= ~0x00008000;
 208                         wrmsr(MSR_K7_HWCR, l, h);
 209                         set_cpu_cap(c, X86_FEATURE_XMM);
 210                 }
 211         }
 212
 213         /*
 214          * It's been determined by AMD that Athlons since model 8 stepping 1
 215          * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
 216          * As per AMD technical note 27212 0.2
 217          */
 218         if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
 219                 rdmsr(MSR_K7_CLK_CTL, l, h);
 220                 if ((l & 0xfff00000) != 0x20000000) {
 221                         printk ("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n", l,
 222                                 ((l & 0x000fffff)|0x20000000));
 223                         wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
 224                 }
 225         }
 226
 227         set_cpu_cap(c, X86_FEATURE_K7);
 228
 229         amd_k7_smp_check(c);
 230 }
 231 #endif
 232
 233 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
 234 static int __cpuinit nearby_node(int apicid)
 235 {
 236         int i, node;
 237
 238         for (i = apicid - 1; i >= 0; i--) {
 239                 node = apicid_to_node[i];
 240                 if (node != NUMA_NO_NODE && node_online(node))
 241                         return node;
 242         }
 243         for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
 244                 node = apicid_to_node[i];
 245                 if (node != NUMA_NO_NODE && node_online(node))
 246                         return node;
 247         }
 248         return first_node(node_online_map); /* Shouldn't happen */
 249 }
 250 #endif
 251
 252 /*
 253  * On a AMD dual core setup the lower bits of the APIC id distingush the cores.
 254  * Assumes number of cores is a power of two.
 255  */
 256 static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
 257 {
 258 #ifdef CONFIG_X86_HT
 259         unsigned bits;
 260
 261         bits = c->x86_coreid_bits;
 262
 263         /* Low order bits define the core id (index of core in socket) */
 264         c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
 265         /* Convert the initial APIC ID into the socket ID */
 266         c->phys_proc_id = c->initial_apicid >> bits;
 267 #endif
 268 }
 269
 270 static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
 271 {
 272 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
 273         int cpu = smp_processor_id();
 274         int node;
 275         unsigned apicid = hard_smp_processor_id();
 276
 277         node = c->phys_proc_id;
 278         if (apicid_to_node[apicid] != NUMA_NO_NODE)
 279                 node = apicid_to_node[apicid];
 280         if (!node_online(node)) {
 281                 /* Two possibilities here:
 282                    - The CPU is missing memory and no node was created.
 283                    In that case try picking one from a nearby CPU
 284                    - The APIC IDs differ from the HyperTransport node IDs
 285                    which the K8 northbridge parsing fills in.
 286                    Assume they are all increased by a constant offset,
 287                    but in the same order as the HT nodeids.
 288                    If that doesn't result in a usable node fall back to the
 289                    path for the previous case.  */
 290
 291                 int ht_nodeid = c->initial_apicid;
 292
 293                 if (ht_nodeid >= 0 &&
 294                     apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
 295                         node = apicid_to_node[ht_nodeid];
 296                 /* Pick a nearby node */
 297                 if (!node_online(node))
 298                         node = nearby_node(apicid);
 299         }
 300         numa_set_node(cpu, node);
 301
 302         printk(KERN_INFO "CPU %d/0x%x -> Node %d\n", cpu, apicid, node);
 303 #endif
 304 }
 305
 306 static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
 307 {
 308 #ifdef CONFIG_X86_HT
 309         unsigned bits, ecx;
 310
 311         /* Multi core CPU? */
 312         if (c->extended_cpuid_level < 0x80000008)
 313                 return;
 314
 315         ecx = cpuid_ecx(0x80000008);
 316
 317         c->x86_max_cores = (ecx & 0xff) + 1;
 318
 319         /* CPU telling us the core id bits shift? */
 320         bits = (ecx >> 12) & 0xF;
 321
 322         /* Otherwise recompute */
 323         if (bits == 0) {
 324                 while ((1 << bits) < c->x86_max_cores)
 325                         bits++;
 326         }
 327
 328         c->x86_coreid_bits = bits;
 329 #endif
 330 }
 331
 332 static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
 333 {
 334         early_init_amd_mc(c);
 335
 336         /*
 337          * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
 338          * with P/T states and does not stop in deep C-states
 339          */
 340         if (c->x86_power & (1 << 8)) {
 341                 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 342                 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
 343         }
 344
 345 #ifdef CONFIG_X86_64
 346         set_cpu_cap(c, X86_FEATURE_SYSCALL32);
 347 #else
 348         /*  Set MTRR capability flag if appropriate */
 349         if (c->x86 == 5)
 350                 if (c->x86_model == 13 || c->x86_model == 9 ||
 351                     (c->x86_model == 8 && c->x86_mask >= 8))
 352                         set_cpu_cap(c, X86_FEATURE_K6_MTRR);
 353 #endif
 354 }
 355
 356 static void __cpuinit init_amd(struct cpuinfo_x86 *c)
 357 {
 358 #ifdef CONFIG_SMP
 359         unsigned long long value;
 360
 361         /*
 362          * Disable TLB flush filter by setting HWCR.FFDIS on K8
 363          * bit 6 of msr C001_0015
 364          *
 365          * Errata 63 for SH-B3 steppings
 366          * Errata 122 for all steppings (F+ have it disabled by default)
 367          */
 368         if (c->x86 == 0xf) {
 369                 rdmsrl(MSR_K7_HWCR, value);
 370                 value |= 1 << 6;
 371                 wrmsrl(MSR_K7_HWCR, value);
 372         }
 373 #endif
 374
 375         early_init_amd(c);
 376
 377         /*
 378          * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
 379          * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
 380          */
 381         clear_cpu_cap(c, 0*32+31);
 382
 383 #ifdef CONFIG_X86_64
 384         /* On C+ stepping K8 rep microcode works well for copy/memset */
 385         if (c->x86 == 0xf) {
 386                 u32 level;
 387
 388                 level = cpuid_eax(1);
 389                 if((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
 390                         set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 391         }
 392         if (c->x86 == 0x10 || c->x86 == 0x11)
 393                 set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 394 #else
 395
 396         /*
 397          *      FIXME: We should handle the K5 here. Set up the write
 398          *      range and also turn on MSR 83 bits 4 and 31 (write alloc,
 399          *      no bus pipeline)
 400          */
 401
 402         switch (c->x86) {
 403         case 4:
 404                 init_amd_k5(c);
 405                 break;
 406         case 5:
 407                 init_amd_k6(c);
 408                 break;
 409         case 6: /* An Athlon/Duron */
 410                 init_amd_k7(c);
 411                 break;
 412         }
 413
 414         /* K6s reports MCEs but don't actually have all the MSRs */
 415         if (c->x86 < 6)
 416                 clear_cpu_cap(c, X86_FEATURE_MCE);
 417 #endif
 418
 419         /* Enable workaround for FXSAVE leak */
 420         if (c->x86 >= 6)
 421                 set_cpu_cap(c, X86_FEATURE_FXSAVE_LEAK);
 422
 423         if (!c->x86_model_id[0]) {
 424                 switch (c->x86) {
 425                 case 0xf:
 426                         /* Should distinguish Models here, but this is only
 427                            a fallback anyways. */
 428                         strcpy(c->x86_model_id, "Hammer");
 429                         break;
 430                 }
 431         }
 432
 433         display_cacheinfo(c);
 434
 435         /* Multi core CPU? */
 436         if (c->extended_cpuid_level >= 0x80000008) {
 437                 amd_detect_cmp(c);
 438                 srat_detect_node(c);
 439         }
 440
 441 #ifdef CONFIG_X86_32
 442         detect_ht(c);
 443 #endif
 444
 445         if (c->extended_cpuid_level >= 0x80000006) {
 446                 if ((c->x86 >= 0x0f) && (cpuid_edx(0x80000006) & 0xf000))
 447                         num_cache_leaves = 4;
 448                 else
 449                         num_cache_leaves = 3;
 450         }
 451
 452         if (c->x86 >= 0xf && c->x86 <= 0x11)
 453                 set_cpu_cap(c, X86_FEATURE_K8);
 454
 455         if (cpu_has_xmm2) {
 456                 /* MFENCE stops RDTSC speculation */
 457                 set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
 458         }
 459
 460 #ifdef CONFIG_X86_64
 461         if (c->x86 == 0x10) {
 462                 /* do this for boot cpu */
 463                 if (c == &boot_cpu_data)
 464                         check_enable_amd_mmconf_dmi();
 465
 466                 fam10h_check_enable_mmcfg();
 467         }
 468
 469         if (c == &boot_cpu_data && c->x86 >= 0xf && c->x86 <= 0x11) {
 470                 unsigned long long tseg;
 471
 472                 /*
 473                  * Split up direct mapping around the TSEG SMM area.
 474                  * Don't do it for gbpages because there seems very little
 475                  * benefit in doing so.
 476                  */
 477                 if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
 478                     printk(KERN_DEBUG "tseg: %010llx\n", tseg);
 479                     if ((tseg>>PMD_SHIFT) <
 480                                 (max_low_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) ||
 481                         ((tseg>>PMD_SHIFT) <
 482                                 (max_pfn_mapped>>(PMD_SHIFT-PAGE_SHIFT)) &&
 483                          (tseg>>PMD_SHIFT) >= (1ULL<<(32 - PMD_SHIFT))))
 484                         set_memory_4k((unsigned long)__va(tseg), 1);
 485                 }
 486         }
 487 #endif
 488 }
 489
 490 #ifdef CONFIG_X86_32
 491 static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
 492 {
 493         /* AMD errata T13 (order #21922) */
 494         if ((c->x86 == 6)) {
 495                 if (c->x86_model == 3 && c->x86_mask == 0)      /* Duron Rev A0 */
 496                         size = 64;
 497                 if (c->x86_model == 4 &&
 498                     (c->x86_mask == 0 || c->x86_mask == 1))     /* Tbird rev A1/A2 */
 499                         size = 256;
 500         }
 501         return size;
 502 }
 503 #endif
 504
 505 static struct cpu_dev amd_cpu_dev __cpuinitdata = {
 506         .c_vendor       = "AMD",
 507         .c_ident        = { "AuthenticAMD" },
 508 #ifdef CONFIG_X86_32
 509         .c_models = {
 510                 { .vendor = X86_VENDOR_AMD, .family = 4, .model_names =
 511                   {
 512                           [3] = "486 DX/2",
 513                           [7] = "486 DX/2-WB",
 514                           [8] = "486 DX/4",
 515                           [9] = "486 DX/4-WB",
 516                           [14] = "Am5x86-WT",
 517                           [15] = "Am5x86-WB"
 518                   }
 519                 },
 520         },
 521         .c_size_cache   = amd_size_cache,
 522 #endif
 523         .c_early_init   = early_init_amd,
 524         .c_init         = init_amd,
 525         .c_x86_vendor   = X86_VENDOR_AMD,
 526 };
 527
 528 cpu_dev_register(amd_cpu_dev);