src/mesa/ppc/common_ppc.c

   1 /*
   2  * (C) Copyright IBM Corporation 2004
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the "Software"),
   7  * to deal in the Software without restriction, including without limitation
   8  * on the rights to use, copy, modify, merge, publish, distribute, sub
   9  * license, and/or sell copies of the Software, and to permit persons to whom
  10  * the Software is furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice (including the next
  13  * paragraph) shall be included in all copies or substantial portions of the
  14  * Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.  IN NO EVENT SHALL
  19  * IBM AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
  20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  22  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file common_ppc.c
  27  * Check CPU capabilities & initialize optimized funtions for this particular
  28  * processor.
  29  *
  30  * \author Ian Romanick <idr@us.ibm.com>
  31  */
  32
  33 #include <stdio.h>
  34 #include <unistd.h>
  35 #include <sys/types.h>
  36
  37 #ifdef USE_PPC_ASM
  38 #include <elf.h>
  39 #endif
  40
  41 #include "common_ppc_features.h"
  42
  43
  44 unsigned long _mesa_ppc_cpu_features = 0;
  45
  46 /**
  47  * Detect CPU features and install optimized transform and lighting routines.
  48  * Currently, CPU features are only detected.  The optimized routines have
  49  * yet to be written.
  50  *
  51  * \bug
  52  * This routine is highly specific to Linux kernel 2.6.  I'm still waiting
  53  * to hear back from the glibc folk on how to do this "right".
  54  */
  55
  56 void _mesa_init_all_ppc_transform_asm( void )
  57 {
  58 #ifdef USE_PPC_ASM
  59    const pid_t  my_pid = getpid();
  60    char file_name[32];
  61    FILE * f;
  62 #ifdef __powerpc64__
  63    Elf64_auxv_t  v;
  64 #else
  65    Elf32_auxv_t  v;
  66 #endif
  67
  68    sprintf( file_name, "/proc/%u/auxv", (unsigned) my_pid );
  69    f = fopen( file_name, "rb" );
  70    if ( f != NULL ) {
  71       while( 1 ) {
  72          ssize_t elem = fread( & v, sizeof( v ), 1, f );
  73
  74          if ( elem < 1 ) {
  75             break;
  76          }
  77
  78          if ( v.a_type == AT_HWCAP ) {
  79             _mesa_ppc_cpu_features = v.a_un.a_val;
  80             break;
  81          }
  82       }
  83
  84       fclose( f );
  85    }
  86
  87 # ifndef USE_VMX_ASM
  88    _mesa_ppc_cpu_features &= ~PPC_FEATURE_HAS_ALTIVEC;
  89 # endif
  90 #endif
  91 }