0001 .. SPDX-License-Identifier: GPL-2.0
0002
0003 ===============
0004 ACRN CPUID bits
0005 ===============
0006
0007 A guest VM running on an ACRN hypervisor can check some of its features using
0008 CPUID.
0009
0010 ACRN cpuid functions are:
0011
0012 function: 0x40000000
0013
0014 returns::
0015
0016 eax = 0x40000010
0017 ebx = 0x4e524341
0018 ecx = 0x4e524341
0019 edx = 0x4e524341
0020
0021 Note that this value in ebx, ecx and edx corresponds to the string
0022 "ACRNACRNACRN". The value in eax corresponds to the maximum cpuid function
0023 present in this leaf, and will be updated if more functions are added in the
0024 future.
0025
0026 function: define ACRN_CPUID_FEATURES (0x40000001)
0027
0028 returns::
0029
0030 ebx, ecx, edx
0031 eax = an OR'ed group of (1 << flag)
0032
0033 where ``flag`` is defined as below:
0034
0035 ================================= =========== ================================
0036 flag value meaning
0037 ================================= =========== ================================
0038 ACRN_FEATURE_PRIVILEGED_VM 0 guest VM is a privileged VM
0039 ================================= =========== ================================
0040
0041 function: 0x40000010
0042
0043 returns::
0044
0045 ebx, ecx, edx
0046 eax = (Virtual) TSC frequency in kHz.
