mdw@git.distorted.org.uk Git - misc/blob - x86-model.1

   1 .TH x86-model 1 "30 April 2009" "Edgeware tools"
   2 .SH NAME
   3 x86-model \- show x86 CPU model information and (a bit) more
   4 .SH SYNOPSIS
   5 .B x86-model
   6 .RB [ \-v ]
   7 .RB [ \-i \c
   8 .RB | \-d \c
   9 .RB |[ \-s ]
  10 .IR leaf ] \c
  11 .RB | \-x
  12 .IR leaf ]
  13 .SH DESCRIPTION
  14 The
  15 .b x86-model
  16 program shows basic information about the host's x86-based processor,
  17 gleaned from the CPUID instruction.  It doesn't work on other processors
  18 at all.  The
  19 .B \-v
  20 flag causes more detailed information to be output.
  21 .PP
  22 The CPUID instruction reads an index in the EAX register which selects a
  23 `leaf' of information; it sets the output registers EAX, EBX, ECX, and
  24 EDX, to the appropriate values for the selected leaf.
  25 .PP
  26 By default, or with
  27 .BR \-i ,
  28 it shows the `display family' and `display model' information for the
  29 processor, in the form
  30 .IB family _ model H
  31 which is used in the tables in Appendix C of Intel's optimization
  32 guide.  In verbose mode, the processor type, family, model and stepping
  33 are shown separately.
  34 .PP
  35 With the
  36 .B \-d
  37 option, all of the available CPUID information is dumped to standard
  38 output.  Each line has the form
  39 .IP
  40 .IB leaf :
  41 .I eax
  42 .I ebx
  43 .I ecx
  44 .I edx
  45 .PP
  46 Verbose mode makes no difference.
  47 .PP
  48 With the
  49 .B \-s
  50 option (or just a
  51 .I leaf
  52 index), prints the leaf of information selected by
  53 .IR leaf ,
  54 as four hexadecimal numbers separated by spaces.  In verbose mode, the
  55 output is written on four lines, labelled with the appropriate register
  56 names.
  57 .PP
  58 With the
  59 .B \-x
  60 option, the behaviour is as for
  61 .B \-s
  62 except that `extended function' information is selected by toggling bit
  63 31 of the leaf index.
  64 .PP
  65 If no option is given, but there is a command-line argument, then the
  66 behaviour is as for
  67 .B \-s
  68 with the leaf taken from the argument; otherwise the behaviour is as for
  69 .BR \-i .
  70 .SH SEE ALSO
  71 .BR cpuid (1).
  72 .PP
  73 .I "Intel 64 and IA-32 Architectures Software Developer's Manual"
  74 .br
  75 .I "Intel 64 and IA-32 Architectures Optimization Reference Manual"