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Here's the initial draft I had for Intel: Intel CPU model checks ---------------------- Intel CPU model checks should use the combined vendor/family/model field, x86_vfm, together with the INTEL_* defines in asm/intel-family.h. Avoid comparing x86_model against literal model numbers. Instead of writing:: if (c->x86 == 6 && c->x86_model == 0x97) Please use:: if (c->x86_vfm == INTEL_ALDERLAKE) To match several models, prefer an x86_match_cpu() table built with X86_MATCH_VFM(). If a model is missing from asm/intel-family.h, add a define for it. Range checks on x86_vfm can work, but they are discouraged for newer CPUs. Model numbers are not assigned in release order, and the newer Families 18 and 19 interleave with Family 6, which makes ranges hard to get right. IIUC, the AMD usage is primarily geared towards range checks for a group of CPUs whereas the Intel usage is for specific targeted CPUs. Expressing uarch reusing x86_vfm and using it for range checks can be tricky. See below. > amd-family.h is not really necessary right now but that's immaterial for this > change - we can always convert to it later if absolutely necessary. And > I don't think it will be. > ... > @@ -483,13 +482,13 @@ static void bsp_init_amd(struct cpuinfo_x86 *c) > switch (c->x86_model) { > case 0x00 ... 0x2f: > case 0x50 ... 0x5f: > - setup_force_cpu_cap(X86_FEATURE_ZEN1); > + c->x86_vfm = AMD_ZEN1; Since x86_vfm is a union, wouldn't this clobber the vendor, family and model? This will set the x86_vendor to 0 and get detected as an Intel CPU. > break; > case 0x30 ... 0x4f: > case 0x60 ... 0x7f: > case 0x90 ... 0x91: > case 0xa0 ... 0xaf: > - setup_force_cpu_cap(X86_FEATURE_ZEN2); > + c->x86_vfm = AMD_ZEN2; > break; > default: