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			408 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			408 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Get file-specific information about a file.  Linux version.
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|    Copyright (C) 2003, 2004 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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| 
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|    The GNU C Library is free software; you can redistribute it and/or
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|    modify it under the terms of the GNU Lesser General Public
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|    License as published by the Free Software Foundation; either
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|    version 2.1 of the License, or (at your option) any later version.
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| 
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|    The GNU C Library is distributed in the hope that it will be useful,
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|    but WITHOUT ANY WARRANTY; without even the implied warranty of
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|    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|    Lesser General Public License for more details.
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| 
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|    You should have received a copy of the GNU Lesser General Public
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|    License along with the GNU C Library; if not, write to the Free
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|    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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|    02111-1307 USA.  */
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| 
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| #include <assert.h>
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| #include <stdbool.h>
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| #include <stdlib.h>
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| #include <unistd.h>
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| #include <hp-timing.h>
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| 
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| static long int linux_sysconf (int name);
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| 
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| 
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| static long int
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| handle_i486 (int name)
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| {
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|   /* The processor only has a unified level 1 cache of 8k.  */
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|   switch (name)
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|     {
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|     case _SC_LEVEL1_ICACHE_SIZE:
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|     case _SC_LEVEL1_DCACHE_SIZE:
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|       return 8 * 1024;
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| 
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|     case _SC_LEVEL1_ICACHE_ASSOC:
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|     case _SC_LEVEL1_DCACHE_ASSOC:
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|       // XXX Anybody know this?
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|       return 0;
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| 
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|     case _SC_LEVEL1_ICACHE_LINESIZE:
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|     case _SC_LEVEL1_DCACHE_LINESIZE:
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|       // XXX Anybody know for sure?
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|       return 16;
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| 
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|     case _SC_LEVEL2_CACHE_SIZE:
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|     case _SC_LEVEL2_CACHE_ASSOC:
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|     case _SC_LEVEL2_CACHE_LINESIZE:
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|     case _SC_LEVEL3_CACHE_SIZE:
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|     case _SC_LEVEL3_CACHE_ASSOC:
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|     case _SC_LEVEL3_CACHE_LINESIZE:
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|     case _SC_LEVEL4_CACHE_SIZE:
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|     case _SC_LEVEL4_CACHE_ASSOC:
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|       /* Not available.  */
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|       break;
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| 
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|     default:
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|       assert (! "cannot happen");
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|     }
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| 
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|   return -1;
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| }
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| 
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| 
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| static const struct intel_02_cache_info
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| {
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|   unsigned int idx;
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|   int name;
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|   long int size;
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|   long int assoc;
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|   long int linesize;
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| } intel_02_known[] =
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|   {
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|     { 0x06, _SC_LEVEL1_ICACHE_SIZE, 8192, 4, 32 },
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|     { 0x08, _SC_LEVEL1_ICACHE_SIZE, 16384, 4, 32 },
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|     { 0x0a, _SC_LEVEL1_DCACHE_SIZE, 8192, 2, 32 },
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|     { 0x0c, _SC_LEVEL1_DCACHE_SIZE, 16384, 4, 32 },
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|     { 0x22, _SC_LEVEL3_CACHE_SIZE, 524288, 4, 64 },
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|     { 0x23, _SC_LEVEL3_CACHE_SIZE, 1048576, 8, 64 },
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|     { 0x25, _SC_LEVEL3_CACHE_SIZE, 2097152, 8, 64 },
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|     { 0x29, _SC_LEVEL3_CACHE_SIZE, 4194304, 8, 64 },
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|     { 0x2c, _SC_LEVEL1_DCACHE_SIZE, 32768, 8, 64 },
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|     { 0x30, _SC_LEVEL1_ICACHE_SIZE, 32768, 8, 64 },
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|     { 0x41, _SC_LEVEL2_CACHE_SIZE, 131072, 4, 32 },
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|     { 0x42, _SC_LEVEL2_CACHE_SIZE, 262144, 4, 32 },
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|     { 0x43, _SC_LEVEL2_CACHE_SIZE, 524288, 4, 32 },
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|     { 0x44, _SC_LEVEL2_CACHE_SIZE, 1048576, 4, 32 },
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|     { 0x45, _SC_LEVEL2_CACHE_SIZE, 2097152, 4, 32 },
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|     { 0x60, _SC_LEVEL1_DCACHE_SIZE, 16384, 8, 64 },
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|     { 0x66, _SC_LEVEL1_DCACHE_SIZE, 8192, 4, 64 },
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|     { 0x67, _SC_LEVEL1_DCACHE_SIZE, 16384, 4, 64 },
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|     { 0x68, _SC_LEVEL1_DCACHE_SIZE, 32768, 4, 64 },
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|     { 0x78, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 64 },
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|     { 0x79, _SC_LEVEL2_CACHE_SIZE, 131072, 8, 64 },
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|     { 0x7a, _SC_LEVEL2_CACHE_SIZE, 262144, 8, 64 },
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|     { 0x7b, _SC_LEVEL2_CACHE_SIZE, 524288, 8, 64 },
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|     { 0x7c, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 64 },
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|     { 0x7d, _SC_LEVEL2_CACHE_SIZE, 2097152, 8, 64 },
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|     { 0x82, _SC_LEVEL2_CACHE_SIZE, 262144, 8, 32 },
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|     { 0x83, _SC_LEVEL2_CACHE_SIZE, 524288, 8, 32 },
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|     { 0x84, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 32 },
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|     { 0x85, _SC_LEVEL2_CACHE_SIZE, 2097152, 8, 32 },
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|     { 0x86, _SC_LEVEL2_CACHE_SIZE, 524288, 4, 64 },
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|     { 0x87, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 64 },
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|   };
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| #define nintel_02_known (sizeof (intel_02_known) / sizeof (intel_02_known[0]))
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| 
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| 
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| static int
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| intel_02_known_compare (const void *p1, const void *p2)
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| {
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|   const struct intel_02_cache_info *i1;
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|   const struct intel_02_cache_info *i2;
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| 
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|   i1 = (const struct intel_02_cache_info *) p1;
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|   i2 = (const struct intel_02_cache_info *) p2;
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| 
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|   if (i1->idx == i2->idx)
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|     return 0;
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| 
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|   return i1->idx < i2->idx ? -1 : 1;
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| }
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| 
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| 
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| static long int
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| intel_check_word (int name, unsigned int value, bool *has_level_2,
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| 		  bool *no_level_2_or_3)
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| {
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|   if ((value & 0x80000000) != 0)
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|     /* The register value is reserved.  */
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|     return 0;
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| 
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|   /* Fold the name.  The _SC_ constants are always in the order SIZE,
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|      ASSOC, LINESIZE.  */
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|   int folded_name = (_SC_LEVEL1_ICACHE_SIZE
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| 		     + ((name - _SC_LEVEL1_ICACHE_SIZE) / 3) * 3);
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| 
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|   while (value != 0)
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|     {
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|       unsigned int byte = value & 0xff;
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| 
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|       if (byte == 0x40)
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| 	{
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| 	  *no_level_2_or_3 = true;
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| 
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| 	  if (folded_name == _SC_LEVEL3_CACHE_SIZE)
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| 	    /* No need to look further.  */
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| 	    break;
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| 	}
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|       else
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| 	{
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| 	  struct intel_02_cache_info *found;
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| 	  struct intel_02_cache_info search;
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| 
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| 	  search.idx = byte;
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| 	  found = bsearch (&search, intel_02_known, nintel_02_known,
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| 			   sizeof (intel_02_known[0]), intel_02_known_compare);
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| 	  if (found != NULL)
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| 	    {
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| 	      if (found->name == folded_name)
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| 		{
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| 		  unsigned int offset = name - folded_name;
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| 
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| 		  if (offset == 0)
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| 		    /* Cache size.  */
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| 		    return found->size;
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| 		  if (offset == 1)
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| 		    return found->assoc;
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| 
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| 		  assert (offset == 2);
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| 		  return found->linesize;
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| 		}
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| 
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| 	      if (found->name == _SC_LEVEL2_CACHE_SIZE)
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| 		*has_level_2 = true;
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| 	    }
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| 	}
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| 
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|       /* Next byte for the next round.  */
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|       value >>= 8;
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|     }
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| 
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|   /* Nothing found.  */
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|   return 0;
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| }
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| 
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| 
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| static long int
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| handle_intel (int name, unsigned int maxidx)
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| {
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|   if (maxidx < 2)
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|     {
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|       // XXX Do such processors exist?  When we know we can fill in some
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|       // values.
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|       return 0;
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|     }
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| 
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|   /* OK, we can use the CPUID instruction to get all info about the
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|      caches.  */
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|   unsigned int cnt = 0;
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|   unsigned int max = 1;
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|   long int result = 0;
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|   bool no_level_2_or_3 = false;
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|   bool has_level_2 = false;
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|   while (cnt++ < max)
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|     {
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|       unsigned int eax;
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|       unsigned int ebx;
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|       unsigned int ecx;
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|       unsigned int edx;
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|       asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1"
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| 		    : "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx)
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| 		    : "0" (2));
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| 
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|       /* The low byte of EAX in the first round contain the number of
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| 	 rounds we have to make.  At least one, the one we are already
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| 	 doing.  */
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|       if (cnt == 1)
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| 	{
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| 	  max = eax & 0xff;
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| 	  eax &= 0xffffff00;
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| 	}
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| 
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|       /* Process the individual registers' value.  */
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|       result = intel_check_word (name, eax, &has_level_2, &no_level_2_or_3);
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|       if (result != 0)
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| 	return result;
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| 
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|       result = intel_check_word (name, ebx, &has_level_2, &no_level_2_or_3);
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|       if (result != 0)
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| 	return result;
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| 
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|       result = intel_check_word (name, ecx, &has_level_2, &no_level_2_or_3);
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|       if (result != 0)
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| 	return result;
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| 
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|       result = intel_check_word (name, edx, &has_level_2, &no_level_2_or_3);
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|       if (result != 0)
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| 	return result;
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|     }
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| 
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|   if (name >= _SC_LEVEL2_CACHE_SIZE && name <= _SC_LEVEL3_CACHE_LINESIZE
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|       && no_level_2_or_3)
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|     return -1;
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| 
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|   return 0;
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| }
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| 
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| 
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| static long int
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| handle_amd (int name)
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| {
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|   unsigned int eax;
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|   unsigned int ebx;
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|   unsigned int ecx;
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|   unsigned int edx;
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|   asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1"
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| 		: "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx)
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| 		: "0" (0x80000000));
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| 
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|   if (name >= _SC_LEVEL3_CACHE_SIZE)
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|     return 0;
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| 
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|   unsigned int fn = 0x80000005 + (name >= _SC_LEVEL2_CACHE_SIZE);
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|   if (eax < fn)
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|     return 0;
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| 
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|   asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1"
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| 		: "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx)
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| 		: "0" (fn));
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| 
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|   if (name < _SC_LEVEL1_DCACHE_SIZE)
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|     {
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|       name += _SC_LEVEL1_DCACHE_SIZE - _SC_LEVEL1_ICACHE_SIZE;
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|       ecx = edx;
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|     }
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| 
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|   switch (name)
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|     {
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|     case _SC_LEVEL1_DCACHE_SIZE:
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|       return (ecx >> 14) & 0x3fc00;
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|     case _SC_LEVEL1_DCACHE_ASSOC:
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|       ecx >>= 16;
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|       if ((ecx & 0xff) == 0xff)
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| 	/* Fully associative.  */
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| 	return (ecx << 2) & 0x3fc00;
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|       return ecx & 0xff;
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|     case _SC_LEVEL1_DCACHE_LINESIZE:
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|       return ecx & 0xff;
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|     case _SC_LEVEL2_CACHE_SIZE:
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|       return (ecx & 0xf000) == 0 ? 0 : (ecx >> 6) & 0x3fffc00;
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|     case _SC_LEVEL2_CACHE_ASSOC:
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|       ecx >>= 12;
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|       switch (ecx & 0xf)
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|         {
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|         case 0:
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|         case 1:
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|         case 2:
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|         case 4:
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| 	  return ecx & 0xf;
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| 	case 6:
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| 	  return 8;
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| 	case 8:
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| 	  return 16;
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| 	case 0xf:
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| 	  return (ecx << 6) & 0x3fffc00;
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| 	default:
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| 	  return 0;
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|         }
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|     case _SC_LEVEL2_CACHE_LINESIZE:
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|       return (ecx & 0xf000) == 0 ? 0 : ecx & 0xff;
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|     default:
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|       assert (! "cannot happen");
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|     }
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|   return -1;
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| }
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| 
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| 
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| static int
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| i386_i486_test (void)
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| {
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|   int eflags;
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|   int ac;
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|   asm volatile ("pushfl;\n\t"
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| 		"popl %0;\n\t"
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| 		"movl $0x240000, %1;\n\t"
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| 		"xorl %0, %1;\n\t"
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| 		"pushl %1;\n\t"
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| 		"popfl;\n\t"
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| 		"pushfl;\n\t"
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| 		"popl %1;\n\t"
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| 		"xorl %0, %1;\n\t"
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| 		"pushl %0;\n\t"
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| 		"popfl"
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| 		: "=r" (eflags), "=r" (ac));
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| 
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|   return ac;
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| }
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| 
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| 
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| /* Get the value of the system variable NAME.  */
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| long int
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| __sysconf (int name)
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| {
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|   if (name == _SC_CPUTIME || name == _SC_THREAD_CPUTIME)
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|     {
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| #if HP_TIMING_AVAIL
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|       // XXX We can add  here test for machines which cannot support a
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|       // XXX usable TSC.
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|       return 200112L;
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| #else
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|       return -1;
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| #endif
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|     }
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| 
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|   /* All the remainder, except the cache information, is handled in
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|      the generic code.  */
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|   if (name < _SC_LEVEL1_ICACHE_SIZE || name > _SC_LEVEL4_CACHE_LINESIZE)
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|     return linux_sysconf (name);
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| 
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|   /* Recognize i386 and compatible.  These don't have any cache on
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|      board.  */
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|   int ac = i386_i486_test ();
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| 
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|   if (ac == 0)
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|     /* This is an i386.  */
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|     // XXX Is this true for all brands?
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|     return -1;
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| 
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|   /* Detect i486, the last Intel processor without CPUID.  */
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|   if ((ac & (1 << 21)) == 0)
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|     {
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|       /* No CPUID.  */
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|       // XXX Fill in info about other brands.  For now only Intel.
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|       return handle_i486 (name);
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|     }
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| 
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|   /* Find out what brand of processor.  */
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|   unsigned int eax;
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|   unsigned int ebx;
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|   unsigned int ecx;
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|   unsigned int edx;
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|   asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1"
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| 		: "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx)
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| 		: "0" (0));
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| 
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|   /* This spells out "GenuineIntel".  */
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|   if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69)
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|     return handle_intel (name, eax);
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| 
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|   /* This spells out "AuthenticAMD".  */
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|   if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
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|     return handle_amd (name);
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| 
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|   // XXX Fill in more vendors.
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| 
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|   /* CPU not known, we have no information.  */
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|   return 0;
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| }
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| 
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| /* Now the generic Linux version.  */
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| #undef __sysconf
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| #define __sysconf static linux_sysconf
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| #include "../sysconf.c"
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