osfmk/ppc/commpage/commpage.c

   1 /*
   2  * Copyright (c) 2003-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22
  23 /*
  24  *      Here's what to do if you want to add a new routine to the comm page:
  25  *
  26  *              1. Add a definition for it's address in osfmk/ppc/cpu_capabilities.h,
  27  *                 being careful to reserve room for future expansion.
  28  *
  29  *              2. Write one or more versions of the routine, each with it's own
  30  *                 commpage_descriptor.  The tricky part is getting the "special",
  31  *                 "musthave", and "canthave" fields right, so that exactly one
  32  *                 version of the routine is selected for every machine.
  33  *                 The source files should be in osfmk/ppc/commpage/.
  34  *
  35  *              3. Add a ptr to your new commpage_descriptor(s) in the "routines"
  36  *                 static array below.  Of course, you'll also have to declare them
  37  *                 "extern".
  38  *
  39  *              4. Write the code in Libc to use the new routine.
  40  */
  41
  42 #include <mach/mach_types.h>
  43 #include <mach/machine.h>
  44 #include <mach/vm_map.h>
  45 #include <ppc/exception.h>
  46 #include <ppc/machine_routines.h>
  47 #include <machine/cpu_capabilities.h>
  48 #include <machine/commpage.h>
  49 #include <machine/pmap.h>
  50 #include <vm/vm_kern.h>
  51 #include <vm/vm_map.h>
  52 #include <ipc/ipc_port.h>
  53
  54 extern  vm_map_t        com_region_map32;   // the 32-bit shared submap, set up in vm init
  55 extern  vm_map_t        com_region_map64;   // the 64-bit shared submap
  56
  57 char    *commPagePtr32 = NULL;                  // virtual address of 32-bit comm page in kernel map
  58 char    *commPagePtr64 = NULL;                  // and 64-bit commpage
  59 int             _cpu_capabilities = 0;                  // define the capability vector
  60
  61 static  char    *next;                                  // next available byte in comm page
  62 static  int             cur_routine;                    // comm page address of "current" routine
  63 static  int             matched;                                // true if we've found a match for "current" routine
  64 static  char    *commPagePtr;                   // virtual address in kernel of commpage we are working on
  65
  66 extern  commpage_descriptor     compare_and_swap32_on32;
  67 extern  commpage_descriptor     compare_and_swap32_on64;
  68 extern  commpage_descriptor     compare_and_swap64;
  69 extern  commpage_descriptor     atomic_enqueue32;
  70 extern  commpage_descriptor     atomic_enqueue64;
  71 extern  commpage_descriptor     atomic_dequeue32_on32;
  72 extern  commpage_descriptor     atomic_dequeue32_on64;
  73 extern  commpage_descriptor     atomic_dequeue64;
  74 extern  commpage_descriptor     memory_barrier_up;
  75 extern  commpage_descriptor     memory_barrier_mp32;
  76 extern  commpage_descriptor     memory_barrier_mp64;
  77 extern  commpage_descriptor     atomic_add32;
  78 extern  commpage_descriptor     atomic_add64;
  79 extern  commpage_descriptor     mach_absolute_time_32;
  80 extern  commpage_descriptor     mach_absolute_time_64;
  81 extern  commpage_descriptor     mach_absolute_time_lp64;
  82 extern  commpage_descriptor     spinlock_32_try_mp;
  83 extern  commpage_descriptor     spinlock_32_try_up;
  84 extern  commpage_descriptor     spinlock_64_try_mp;
  85 extern  commpage_descriptor     spinlock_64_try_up;
  86 extern  commpage_descriptor     spinlock_32_lock_mp;
  87 extern  commpage_descriptor     spinlock_32_lock_up;
  88 extern  commpage_descriptor     spinlock_64_lock_mp;
  89 extern  commpage_descriptor     spinlock_64_lock_up;
  90 extern  commpage_descriptor     spinlock_32_unlock_mp;
  91 extern  commpage_descriptor     spinlock_32_unlock_up;
  92 extern  commpage_descriptor     spinlock_64_unlock_mp;
  93 extern  commpage_descriptor     spinlock_64_unlock_up;
  94 extern  commpage_descriptor     pthread_getspecific_sprg3_32;
  95 extern  commpage_descriptor     pthread_getspecific_sprg3_64;
  96 extern  commpage_descriptor     pthread_getspecific_uftrap;
  97 extern  commpage_descriptor     gettimeofday_32;
  98 extern  commpage_descriptor     gettimeofday_g5_32;
  99 extern  commpage_descriptor     gettimeofday_g5_64;
 100 extern  commpage_descriptor     commpage_flush_dcache;
 101 extern  commpage_descriptor     commpage_flush_icache;
 102 extern  commpage_descriptor     pthread_self_sprg3;
 103 extern  commpage_descriptor     pthread_self_uftrap;
 104 extern  commpage_descriptor     spinlock_relinquish;
 105 extern  commpage_descriptor     bzero_32;
 106 extern  commpage_descriptor     bzero_128;
 107 extern  commpage_descriptor     bcopy_g3;
 108 extern  commpage_descriptor     bcopy_g4;
 109 extern  commpage_descriptor     bcopy_970;
 110 extern  commpage_descriptor     bcopy_64;
 111 extern  commpage_descriptor     compare_and_swap32_on32b;
 112 extern  commpage_descriptor     compare_and_swap32_on64b;
 113 extern  commpage_descriptor     compare_and_swap64b;
 114 extern  commpage_descriptor memset_64;
 115 extern  commpage_descriptor memset_g3;
 116 extern  commpage_descriptor memset_g4;
 117 extern  commpage_descriptor memset_g5;
 118 extern  commpage_descriptor     bigcopy_970;
 119
 120 /* The list of all possible commpage routines.  WARNING: the check for overlap
 121  * assumes that these routines are in strictly ascending order, sorted by address
 122  * in the commpage.  We panic if not.
 123  */
 124 static  commpage_descriptor     *routines[] = {
 125     &compare_and_swap32_on32,
 126     &compare_and_swap32_on64,
 127     &compare_and_swap64,
 128     &atomic_enqueue32,
 129     &atomic_enqueue64,
 130     &atomic_dequeue32_on32,
 131     &atomic_dequeue32_on64,
 132     &atomic_dequeue64,
 133     &memory_barrier_up,
 134     &memory_barrier_mp32,
 135     &memory_barrier_mp64,
 136     &atomic_add32,
 137     &atomic_add64,
 138     &mach_absolute_time_32,
 139     &mach_absolute_time_64,
 140     &mach_absolute_time_lp64,
 141     &spinlock_32_try_mp,
 142     &spinlock_32_try_up,
 143     &spinlock_64_try_mp,
 144     &spinlock_64_try_up,
 145     &spinlock_32_lock_mp,
 146     &spinlock_32_lock_up,
 147     &spinlock_64_lock_mp,
 148     &spinlock_64_lock_up,
 149     &spinlock_32_unlock_mp,
 150     &spinlock_32_unlock_up,
 151     &spinlock_64_unlock_mp,
 152     &spinlock_64_unlock_up,
 153     &pthread_getspecific_sprg3_32,
 154     &pthread_getspecific_sprg3_64,
 155     &pthread_getspecific_uftrap,
 156     &gettimeofday_32,
 157     &gettimeofday_g5_32,
 158     &gettimeofday_g5_64,
 159     &commpage_flush_dcache,
 160     &commpage_flush_icache,
 161     &pthread_self_sprg3,
 162     &pthread_self_uftrap,
 163     &spinlock_relinquish,
 164     &bzero_32,
 165     &bzero_128,
 166     &bcopy_g3,
 167     &bcopy_g4,
 168     &bcopy_970,
 169     &bcopy_64,
 170     &compare_and_swap32_on32b,
 171     &compare_and_swap32_on64b,
 172     &compare_and_swap64b,
 173     &memset_64,
 174     &memset_g3,
 175     &memset_g4,
 176     &memset_g5,
 177     &bigcopy_970,
 178     NULL };
 179
 180
 181 /* Allocate the commpages and add to one of the shared submaps created by vm.
 182  * Called once each for the 32 and 64-bit submaps.
 183  *      1. allocate pages in the kernel map (RW)
 184  *      2. wire them down
 185  *      3. make a memory entry out of them
 186  *      4. map that entry into the shared comm region map (R-only)
 187  */
 188 static  void*
 189 commpage_allocate(
 190         vm_map_t                        submap )                                        // com_region_map32 or com_region_map64
 191 {
 192     vm_offset_t                 kernel_addr;                            // address of commpage in kernel map
 193     vm_offset_t                 zero = 0;
 194     vm_size_t                   size = _COMM_PAGE_AREA_USED;    // size actually populated
 195     vm_map_entry_t              entry;
 196     ipc_port_t                  handle;
 197
 198     if (submap == NULL)
 199         panic("commpage submap is null");
 200
 201     if (vm_allocate(kernel_map,&kernel_addr,_COMM_PAGE_AREA_USED,VM_FLAGS_ANYWHERE))
 202         panic("cannot allocate commpage");
 203
 204     if (vm_map_wire(kernel_map,kernel_addr,kernel_addr+_COMM_PAGE_AREA_USED,VM_PROT_DEFAULT,FALSE))
 205         panic("cannot wire commpage");
 206
 207     /*
 208      * Now that the object is created and wired into the kernel map, mark it so that no delay
 209      * copy-on-write will ever be performed on it as a result of mapping it into user-space.
 210      * If such a delayed copy ever occurred, we could remove the kernel's wired mapping - and
 211      * that would be a real disaster.
 212      *
 213      * JMM - What we really need is a way to create it like this in the first place.
 214      */
 215     if (!vm_map_lookup_entry( kernel_map, vm_map_trunc_page(kernel_addr), &entry) || entry->is_sub_map)
 216         panic("cannot find commpage entry");
 217     entry->object.vm_object->copy_strategy = MEMORY_OBJECT_COPY_NONE;
 218
 219     if (mach_make_memory_entry( kernel_map,                     // target map
 220                                 &size,                          // size
 221                                 kernel_addr,            // offset (address in kernel map)
 222                                 VM_PROT_DEFAULT,        // map it RW
 223                                 &handle,                        // this is the object handle we get
 224                                 NULL ))                         // parent_entry
 225         panic("cannot make entry for commpage");
 226
 227     if (vm_map_64(      submap,                                                 // target map (shared submap)
 228                     &zero,                                                      // address (map into 1st page in submap)
 229                     _COMM_PAGE_AREA_USED,                       // size
 230                     0,                                                          // mask
 231                     VM_FLAGS_FIXED,                                     // flags (it must be 1st page in submap)
 232                     handle,                                                     // port is the memory entry we just made
 233                     0,                                                          // offset (map 1st page in memory entry)
 234                     FALSE,                                                      // copy
 235                     VM_PROT_READ,                                       // cur_protection (R-only in user map)
 236                     VM_PROT_READ,                                       // max_protection
 237                     VM_INHERIT_SHARE ))                         // inheritance
 238         panic("cannot map commpage");
 239
 240     ipc_port_release(handle);
 241
 242     return (void*) kernel_addr;                                         // return address in kernel map
 243 }
 244
 245
 246 /* Get address (in kernel map) of a commpage field. */
 247
 248 static  void*
 249 commpage_addr_of(
 250     int         addr_at_runtime )
 251 {
 252     return      (void*) (commPagePtr + addr_at_runtime - _COMM_PAGE_BASE_ADDRESS);
 253 }
 254
 255
 256 /* Determine number of CPUs on this system.  We cannot rely on
 257  * machine_info.max_cpus this early in the boot.
 258  */
 259 static int
 260 commpage_cpus( void )
 261 {
 262     int         cpus;
 263
 264     cpus = ml_get_max_cpus();                   // NB: this call can block
 265
 266     if (cpus == 0)
 267         panic("commpage cpus==0");
 268     if (cpus > 0xFF)
 269         cpus = 0xFF;
 270
 271     return      cpus;
 272 }
 273
 274
 275 /* Initialize kernel version of _cpu_capabilities vector (used by KEXTs.) */
 276
 277 static void
 278 commpage_init_cpu_capabilities( void )
 279 {
 280     procFeatures        *pfp;
 281     int cpus;
 282     int available;
 283
 284     pfp = &(PerProcTable[0].ppe_vaddr->pf);                     // point to features in per-proc
 285     available = pfp->Available;
 286
 287     // If AltiVec is disabled make sure it is not reported as available.
 288     if ((available & pfAltivec) == 0) {
 289         _cpu_capabilities &= ~kHasAltivec;
 290     }
 291
 292     if (_cpu_capabilities & kDcbaAvailable) {           // if this processor has DCBA, time it...
 293         _cpu_capabilities |= commpage_time_dcba();      // ...and set kDcbaRecomended if it helps.
 294     }
 295
 296     cpus = commpage_cpus();                         // how many CPUs do we have
 297     if (cpus == 1) _cpu_capabilities |= kUP;
 298     _cpu_capabilities |= (cpus << kNumCPUsShift);
 299
 300     if (_cpu_capabilities & k64Bit)                 // 64-bit processors use SPRG3 for TLS
 301         _cpu_capabilities |= kFastThreadLocalStorage;
 302 }
 303
 304
 305 /* Copy data into commpage. */
 306
 307 static void
 308 commpage_stuff(
 309     int         address,
 310     const void  *source,
 311     int         length  )
 312 {
 313     char        *dest = commpage_addr_of(address);
 314
 315     if (dest < next)
 316         panic("commpage overlap: %08 - %08X", dest, next);
 317
 318     bcopy((const char*)source,dest,length);
 319
 320     next = (dest + length);
 321 }
 322
 323
 324 /* Modify commpage code in-place for this specific platform. */
 325
 326 static void
 327 commpage_change(
 328     uint32_t    *ptr,
 329     int                 bytes,
 330     uint32_t    search_mask,
 331     uint32_t    search_pattern,
 332     uint32_t    new_mask,
 333     uint32_t    new_pattern,
 334     int                 (*check)(uint32_t instruction)  )
 335 {
 336     int                 words = bytes >> 2;
 337     uint32_t    word;
 338
 339     while( (--words) >= 0 ) {
 340         word = *ptr;
 341         if ((word & search_mask)==search_pattern) {
 342             if ((check==NULL) || (check(word))) {       // check instruction if necessary
 343                 word &= ~new_mask;
 344                 word |= new_pattern;
 345                 *ptr = word;
 346             }
 347         }
 348         ptr++;
 349     }
 350 }
 351
 352
 353 /* Check to see if exactly one bit is set in a MTCRF instruction's FXM field.
 354  */
 355 static int
 356 commpage_onebit(
 357     uint32_t    mtcrf )
 358 {
 359     int x = (mtcrf >> 12) & 0xFF;               // isolate the FXM field of the MTCRF
 360
 361     if (x==0)
 362         panic("commpage bad mtcrf");
 363
 364     return      (x & (x-1))==0 ? 1 : 0;         // return 1 iff exactly 1 bit set in FXM field
 365 }
 366
 367
 368 /* Check to see if a RLWINM (whose ME is 31) is a SRWI.  Since to shift right n bits
 369  * you must "RLWINM ra,rs,32-n,n,31", if (SH+MB)==32 then we have a SRWI.
 370  */
 371 static int
 372 commpage_srwi(
 373         uint32_t        rlwinm )
 374 {
 375         int                     sh = (rlwinm >> 11) & 0x1F;             // extract SH field of RLWINM, ie bits 16-20
 376         int                     mb = (rlwinm >> 6 ) & 0x1F;             // extract MB field of RLWINM, ie bits 21-25
 377
 378         return  (sh + mb) == 32;                                        // it is a SRWI if (SH+MB)==32
 379 }
 380
 381
 382 /* Handle kCommPageDCBA bit: the commpage routine uses DCBA.  If the machine we're
 383  * running on doesn't benefit from use of that instruction, map them to NOPs
 384  * in the commpage.
 385  */
 386 static void
 387 commpage_handle_dcbas(
 388     int         address,
 389     int         length  )
 390 {
 391     uint32_t    *ptr, search_mask, search, replace_mask, replace;
 392
 393     if ( (_cpu_capabilities & kDcbaRecommended) == 0 ) {
 394         ptr = commpage_addr_of(address);
 395
 396         search_mask =   0xFC0007FE;             // search x-form opcode bits
 397         search =                0x7C0005EC;             // for a DCBA
 398         replace_mask =  0xFFFFFFFF;             // replace all bits...
 399         replace =               0x60000000;             // ...with a NOP
 400
 401         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 402     }
 403 }
 404
 405
 406 /* Handle kCommPageSYNC bit: this routine uses SYNC, LWSYNC, or EIEIO.  If we're
 407  * running on a UP machine, map them to NOPs.
 408  */
 409 static void
 410 commpage_handle_syncs(
 411     int         address,
 412     int         length  )
 413 {
 414     uint32_t    *ptr, search_mask, search, replace_mask, replace;
 415
 416     if (_NumCPUs() == 1) {
 417         ptr = commpage_addr_of(address);
 418
 419         search_mask =   0xFC0005FE;             // search x-form opcode bits (but ignore bit 0x00000200)
 420         search =                0x7C0004AC;             // for a SYNC, LWSYNC, or EIEIO
 421         replace_mask =  0xFFFFFFFF;             // replace all bits...
 422         replace =               0x60000000;             // ...with a NOP
 423
 424         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 425     }
 426 }
 427
 428
 429 /* Handle kCommPageISYNC bit: this routine uses ISYNCs.  If we're running on a UP machine,
 430  * map them to NOPs.
 431  */
 432 static void
 433 commpage_handle_isyncs(
 434     int         address,
 435     int         length  )
 436 {
 437     uint32_t    *ptr, search_mask, search, replace_mask, replace;
 438
 439     if (_NumCPUs() == 1) {
 440         ptr = commpage_addr_of(address);
 441
 442         search_mask =   0xFC0007FE;             // search xl-form opcode bits
 443         search =                0x4C00012C;             // for an ISYNC
 444         replace_mask =  0xFFFFFFFF;             // replace all bits...
 445         replace =               0x60000000;             // ...with a NOP
 446
 447         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 448     }
 449 }
 450
 451
 452 /* Handle kCommPageMTCRF bit.  When this was written (3/03), the assembler did not
 453  * recognize the special form of MTCRF instructions, in which exactly one bit is set
 454  * in the 8-bit mask field.  Bit 11 of the instruction should be set in this case,
 455  * since the 970 and probably other 64-bit processors optimize it.  Once the assembler
 456  * has been updated this code can be removed, though it need not be.
 457  */
 458 static void
 459 commpage_handle_mtcrfs(
 460     int         address,
 461     int         length  )
 462 {
 463     uint32_t    *ptr, search_mask, search, replace_mask, replace;
 464
 465     if (_cpu_capabilities & k64Bit) {
 466         ptr = commpage_addr_of(address);
 467
 468         search_mask =   0xFC0007FE;             // search x-form opcode bits
 469         search =                0x7C000120;             // for a MTCRF
 470         replace_mask =  0x00100000;             // replace bit 11...
 471         replace =               0x00100000;             // ...with a 1-bit
 472
 473         commpage_change(ptr,length,search_mask,search,replace_mask,replace,commpage_onebit);
 474     }
 475 }
 476
 477
 478 /* Port 32-bit code to 64-bit for use in the 64-bit commpage.  This sounds fancier than
 479  * it is.  We do the following:
 480  *              - map "cmpw*" into "cmpd*"
 481  *              - map "srwi" into "srdi"
 482  * Perhaps surprisingly, this is enough to permit lots of code to run in 64-bit mode, as
 483  * long as it is written with this in mind.
 484  */
 485 static void
 486 commpage_port_32_to_64(
 487     int         address,
 488     int         length  )
 489 {
 490     uint32_t    *ptr, search_mask, search, replace_mask, replace;
 491
 492         ptr = commpage_addr_of(address);
 493
 494         search_mask =   0xFC2007FE;             // search x-form opcode bits (and L bit)
 495         search =                0x7C000000;             // for a CMPW
 496         replace_mask =  0x00200000;             // replace bit 10 (L)...
 497         replace =               0x00200000;             // ...with a 1-bit, converting word to doubleword compares
 498         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 499
 500         search_mask =   0xFC2007FE;             // search x-form opcode bits (and L bit)
 501         search =                0x7C000040;             // for a CMPLW
 502         replace_mask =  0x00200000;             // replace bit 10 (L)...
 503         replace =               0x00200000;             // ...with a 1-bit, converting word to doubleword compares
 504         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 505
 506         search_mask =   0xFC200000;             // search d-form opcode bits (and L bit)
 507         search =                0x28000000;             // for a CMPLWI
 508         replace_mask =  0x00200000;             // replace bit 10 (L)...
 509         replace =               0x00200000;             // ...with a 1-bit, converting word to doubleword compares
 510         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 511
 512         search_mask =   0xFC200000;             // search d-form opcode bits (and L bit)
 513         search =                0x2C000000;             // for a CMPWI
 514         replace_mask =  0x00200000;             // replace bit 10 (L)...
 515         replace =               0x00200000;             // ...with a 1-bit, converting word to doubleword compares
 516         commpage_change(ptr,length,search_mask,search,replace_mask,replace,NULL);
 517
 518         search_mask =   0xFC00003E;             // search d-form opcode bits and ME (mask end) field
 519         search =                0x5400003E;             // for an RLWINM with ME=31 (which might be a "srwi")
 520         replace_mask =  0xFC00003E;             // then replace RLWINM's opcode and ME field to make a RLDICL
 521         replace =               0x78000002;             // opcode is 30, ME is 0, except we add 32 to SH amount
 522         commpage_change(ptr,length,search_mask,search,replace_mask,replace,commpage_srwi);
 523 }
 524
 525
 526 /* Copy a routine into comm page if it matches running machine.
 527  */
 528 static void
 529 commpage_stuff_routine(
 530     commpage_descriptor *rd,
 531         int                                     mode )                          // kCommPage32 or kCommPage64
 532 {
 533     char        *routine_code;
 534     int         must,cant;
 535
 536         if ( (rd->special & mode) == 0 )                // is this routine useable in this mode?
 537                 return;
 538
 539     if (rd->commpage_address != cur_routine) {
 540         if ((cur_routine!=0) && (matched==0))
 541             panic("commpage no match for last, next address %08x", rd->commpage_address);
 542         cur_routine = rd->commpage_address;
 543         matched = 0;
 544     }
 545
 546     must = _cpu_capabilities & rd->musthave;
 547     cant = _cpu_capabilities & rd->canthave;
 548
 549     if ((must == rd->musthave) && (cant == 0)) {
 550         if (matched)
 551             panic("commpage multiple matches for address %08x", rd->commpage_address);
 552         matched = 1;
 553         routine_code = ((char*)rd) + rd->code_offset;
 554
 555         commpage_stuff(rd->commpage_address,routine_code,rd->code_length);
 556
 557         if (rd->special & kCommPageDCBA)
 558             commpage_handle_dcbas(rd->commpage_address,rd->code_length);
 559
 560         if (rd->special & kCommPageSYNC)
 561             commpage_handle_syncs(rd->commpage_address,rd->code_length);
 562
 563         if (rd->special & kCommPageISYNC)
 564             commpage_handle_isyncs(rd->commpage_address,rd->code_length);
 565
 566         if (rd->special & kCommPageMTCRF)
 567             commpage_handle_mtcrfs(rd->commpage_address,rd->code_length);
 568
 569                 if ((mode == kCommPage64) && (rd->special & kPort32to64))
 570                         commpage_port_32_to_64(rd->commpage_address,rd->code_length);
 571     }
 572 }
 573
 574
 575 /* Fill in the 32- or 64-bit commpage.  Called once for each.  */
 576
 577 static void
 578 commpage_populate_one(
 579         vm_map_t        submap,                 // the map to populate
 580         char    **  kernAddressPtr,     // address within kernel of this commpage
 581         int                     mode,           // either kCommPage32 or kCommPage64
 582     const char* signature )     // "commpage 32-bit" or "commpage 64-bit"
 583 {
 584     char        c1;
 585     short       c2;
 586     addr64_t c8;
 587     static double       two52 = 1048576.0 * 1048576.0 * 4096.0; // 2**52
 588     static double       ten6 = 1000000.0;                                               // 10**6
 589     static uint64_t magicFE = 0xFEFEFEFEFEFEFEFFLL;         // used to find 0s in strings
 590     static uint64_t magic80 = 0x8080808080808080LL;         // also used to find 0s
 591     commpage_descriptor **rd;
 592     short       version = _COMM_PAGE_THIS_VERSION;
 593
 594     next = NULL;                                                                // initialize next available byte in the commpage
 595         cur_routine = 0;                                                        // initialize comm page address of "current" routine
 596
 597     commPagePtr = (char*) commpage_allocate( submap );
 598     *kernAddressPtr = commPagePtr;                              // save address either in commPagePtr32 or 64
 599
 600     /* Stuff in the constants.  We move things into the comm page in strictly
 601      * ascending order, so we can check for overlap and panic if so.
 602      */
 603
 604     commpage_stuff(_COMM_PAGE_SIGNATURE,signature,strlen(signature));
 605
 606     commpage_stuff(_COMM_PAGE_VERSION,&version,2);
 607
 608     commpage_stuff(_COMM_PAGE_CPU_CAPABILITIES,&_cpu_capabilities,sizeof(int));
 609
 610     c1 = (_cpu_capabilities & kHasAltivec) ? -1 : 0;
 611     commpage_stuff(_COMM_PAGE_ALTIVEC,&c1,1);
 612
 613     c1 = (_cpu_capabilities & k64Bit) ? -1 : 0;
 614     commpage_stuff(_COMM_PAGE_64_BIT,&c1,1);
 615
 616     if (_cpu_capabilities & kCache32)
 617         c2 = 32;
 618     else if (_cpu_capabilities & kCache64)
 619         c2 = 64;
 620     else if (_cpu_capabilities & kCache128)
 621         c2 = 128;
 622     commpage_stuff(_COMM_PAGE_CACHE_LINESIZE,&c2,2);
 623
 624     commpage_stuff(_COMM_PAGE_2_TO_52,&two52,8);
 625     commpage_stuff(_COMM_PAGE_10_TO_6,&ten6,8);
 626     commpage_stuff(_COMM_PAGE_MAGIC_FE,&magicFE,8);
 627     commpage_stuff(_COMM_PAGE_MAGIC_80,&magic80,8);
 628
 629     c8 = 0;                                                                                                     // 0 timestamp means "disabled"
 630     commpage_stuff(_COMM_PAGE_TIMEBASE,&c8,8);
 631     commpage_stuff(_COMM_PAGE_TIMESTAMP,&c8,8);
 632     commpage_stuff(_COMM_PAGE_SEC_PER_TICK,&c8,8);
 633
 634     /* Now the routines.  We try each potential routine in turn,
 635      * and copy in any that "match" the platform we are running on.
 636      * We require that exactly one routine match for each slot in the
 637      * comm page, and panic if not.
 638      */
 639
 640     for( rd = routines; *rd != NULL ; rd++ )
 641         commpage_stuff_routine(*rd,mode);
 642
 643     if (!matched)
 644         panic("commpage no match on last routine");
 645
 646     if (next > (commPagePtr + _COMM_PAGE_AREA_USED))
 647         panic("commpage overflow");
 648
 649
 650         // make all that new code executable
 651
 652     sync_cache_virtual((vm_offset_t) commPagePtr,_COMM_PAGE_AREA_USED);
 653 }
 654
 655
 656 /* Fill in commpage: called once, during kernel initialization, from the
 657  * startup thread before user-mode code is running.
 658  *
 659  * See the top of this file for a list of what you have to do to add
 660  * a new routine to the commpage.
 661  */
 662
 663 void
 664 commpage_populate( void )
 665 {
 666     commpage_init_cpu_capabilities();
 667         commpage_populate_one( com_region_map32, &commPagePtr32, kCommPage32, "commpage 32-bit");
 668         if (_cpu_capabilities & k64Bit) {
 669                 commpage_populate_one( com_region_map64, &commPagePtr64, kCommPage64, "commpage 64-bit");
 670                 pmap_init_sharedpage((vm_offset_t)commPagePtr64);                       // Do the 64-bit version
 671         }
 672
 673 }