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cmd:cpuid [2012/06/06 23:29] 127.0.0.1 external edit |
cmd:cpuid [2012/06/12 10:05] mcb30 |
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| ===== Synopsis ===== | ===== Synopsis ===== | ||
| - | cpuid [--amd] [--ecx] <bit number> | + | cpuid [--ext] [--ecx] <bit number> |
| ===== Examples ===== | ===== Examples ===== | ||
| Line 9: | Line 9: | ||
| === Check if CPU supports 64-bit operation ("long mode") === | === Check if CPU supports 64-bit operation ("long mode") === | ||
| - | cpuid --amd 29 && set arch x86_64 || set arch i386 | + | cpuid --ext 29 && set arch x86_64 || set arch i386 |
| === Check if CPU supports physical address extensions ("PAE") === | === Check if CPU supports physical address extensions ("PAE") === | ||
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| cpuid --ecx 5 && set vmx yes || | cpuid --ecx 5 && set vmx yes || | ||
| - | cpuid --amd --ecx 2 && set svm yes || | + | cpuid --ext --ecx 2 && set svm yes || |
| isset ${vmx} || isset ${svm} && set hw_virt yes || | isset ${vmx} || isset ${svm} && set hw_virt yes || | ||
| ===== Description ===== | ===== Description ===== | ||
| - | Check for the existence of the specified x86 CPU feature using the ''[[http://en.wikipedia.org/wiki/CPUID|CPUID]]'' instruction. If the ''%%--amd%%'' option is specified then the [[http://support.amd.com/us/Embedded_TechDocs/25481.pdf|AMD-defined ("extended") feature set]] is checked, otherwise the [[http://download.intel.com/design/processor/applnots/24161832.pdf|Intel-defined ("standard") feature set]] is checked. If the ''%%--ecx%%'' option is specified then the feature set contained in the ''%%%ecx%%'' register is checked, otherwise the feature set contained in the ''%%%edx%%'' register is checked. | + | Check for the existence of the specified x86 CPU feature using the ''[[http://en.wikipedia.org/wiki/CPUID|CPUID]]'' instruction. If the ''%%--ext%%'' option is specified then the [[http://support.amd.com/us/Embedded_TechDocs/25481.pdf|extended feature set]] is checked, otherwise the [[http://download.intel.com/design/processor/applnots/24161832.pdf|standard feature set]] is checked. If the ''%%--ecx%%'' option is specified then the feature set contained in the ''%%%ecx%%'' register is checked, otherwise the feature set contained in the ''%%%edx%%'' register is checked. |
| Some useful features to check are: | Some useful features to check are: | ||
| ^ Feature set ^ Register ^ Bit ^ Feature ^ Command | | ^ Feature set ^ Register ^ Bit ^ Feature ^ Command | | ||
| - | | AMD | ''%%%edx%%'' | 29 ^ Long mode (64-bit) | ''%%cpuid --amd 29%%'' | | + | | Extended | ''%%%edx%%'' | 29 ^ Long mode (64-bit) | ''%%cpuid --ext 29%%'' | |
| - | | Intel | ''%%%edx%%'' | 6 ^ Physical address extensions (PAE) | ''%%cpuid 6%%'' | | + | | Standard | ''%%%edx%%'' | 6 ^ Physical address extensions (PAE) | ''%%cpuid 6%%'' | |
| - | | Intel | ''%%%ecx%%'' | 5 ^ Virtual Machine Extensions (VMX) | ''%%cpuid --ecx 5%%'' | | + | | Standard | ''%%%ecx%%'' | 5 ^ Virtual Machine Extensions (VMX) | ''%%cpuid --ecx 5%%'' | |
| - | | AMD | ''%%%ecx%%'' | 2 ^ Secure Virtual Machine (SVM) | ''%%cpuid --amd --ecx 2%%'' | | + | | Extended | ''%%%ecx%%'' | 2 ^ Secure Virtual Machine (SVM) | ''%%cpuid --ext --ecx 2%%'' | |
| - | | Intel | ''%%%edx%%'' | 15 ^ Conditional Move (CMOV) | ''%%cpuid 15%%'' | | + | | Standard | ''%%%edx%%'' | 15 ^ Conditional Move (CMOV) | ''%%cpuid 15%%'' | |
| ===== Command status ===== | ===== Command status ===== | ||
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| ===== Notes ===== | ===== Notes ===== | ||
| - | The [[http://download.intel.com/design/processor/applnots/24161832.pdf|Intel-defined ("standard") feature set]] represents the values returned in ''%%%ecx%%'' and ''%%%edx%%'' when ''CPUID'' is called with ''%%%eax=0x00000001%%''. | + | The [[http://download.intel.com/design/processor/applnots/24161832.pdf|standard feature set]] represents the values returned in ''%%%ecx%%'' and ''%%%edx%%'' when ''CPUID'' is called with ''%%%eax=0x00000001%%''. |
| - | The [[http://support.amd.com/us/Embedded_TechDocs/25481.pdf|AMD-defined ("extended") feature set]] represents the values returned in ''%%%ecx%%'' and ''%%%edx%%'' when ''CPUID'' is called with ''%%%eax=0x80000001%%''. | + | The [[http://support.amd.com/us/Embedded_TechDocs/25481.pdf|extended feature set]] represents the values returned in ''%%%ecx%%'' and ''%%%edx%%'' when ''CPUID'' is called with ''%%%eax=0x80000001%%''. |
