CPUID settings



Header file

Configured via config/settings.h.


Enable CPUID settings

  #define CPUID_SETTINGS        /* CPUID settings */


This build option enables support for the CPUID settings, which expose information retrieved using the CPUID instruction.

The CPU vendor and model can be retrieved using the cpuvendor and cpumodel settings.

Other information can be retrieved by constructing a numbered setting using the syntax ${cpuid/<register>.<function>}}, where <function> is the CPUID function number and <register> indicates the CPU register in which the information is returned (encoded as %eax=0, %ebx=1, %ecx=2, %edx=3). For example ${cpuid/2.0x80000001} will give the value of %ecx after calling CPUID with %eax=0x80000001.

For some CPUID leaves (such as %eax=0x00000004), there is also a subfunction number. This may be specified using the syntax ${cpuid/<subfunction>.0x40.<register>.<function>}.

See also

buildcfg/cpuid_settings.txt ยท Last modified: 2021/08/02 11:31 by mcb30
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