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[X86] Fix AMD Znver3 model checks
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Authored by lebedev.ri on Mar 15 2022, 8:32 AM.

Details

Summary

While -march= is correctly detected as znver3 for the cpu,
apparently the model check is incorrect:

$ lscpu 
Architecture:            x86_64
  CPU op-mode(s):        32-bit, 64-bit
  Address sizes:         48 bits physical, 48 bits virtual
  Byte Order:            Little Endian
CPU(s):                  32
  On-line CPU(s) list:   0-31
Vendor ID:               AuthenticAMD
  Model name:            AMD Ryzen 9 5950X 16-Core Processor
    CPU family:          25
    Model:               33
    Thread(s) per core:  2
    Core(s) per socket:  16
    Socket(s):           1
    Stepping:            0
    Frequency boost:     disabled
    CPU max MHz:         6017.8462
    CPU min MHz:         2200.0000
    BogoMIPS:            8050.07
    Flags:               fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf rapl pni pclmulqdq monitor ssse
                         3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt tce topoext perfctr_core perfctr_nb bpext perfctr_llc mwaitx cpb cat_l3 cdp_l3 hw_p
                         state ssbd mba ibrs ibpb stibp vmmcall fsgsbase bmi1 avx2 smep bmi2 erms invpcid cqm rdt_a rdseed adx smap clflushopt clwb sha_ni xsaveopt xsavec xgetbv1 xsaves cqm_llc cqm_occup_llc cqm_mbm_total cqm_mbm_local clzero irperf xsaveerptr rdpru wbn
                         oinvd arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold avic v_vmsave_vmload vgif v_spec_ctrl umip pku ospke vaes vpclmulqdq rdpid overflow_recov succor smca fsrm
Virtualization features: 
  Virtualization:        AMD-V
Caches (sum of all):     
  L1d:                   512 KiB (16 instances)
  L1i:                   512 KiB (16 instances)
  L2:                    8 MiB (16 instances)
  L3:                    64 MiB (2 instances)
NUMA:                    
  NUMA node(s):          1
  NUMA node0 CPU(s):     0-31
Vulnerabilities:         
  Itlb multihit:         Not affected
  L1tf:                  Not affected
  Mds:                   Not affected
  Meltdown:              Not affected
  Spec store bypass:     Mitigation; Speculative Store Bypass disabled via prctl
  Spectre v1:            Mitigation; usercopy/swapgs barriers and __user pointer sanitization
  Spectre v2:            Mitigation; Retpolines, IBPB conditional, IBRS_FW, STIBP always-on, RSB filling
  Srbds:                 Not affected
  Tsx async abort:       Not affected

Model is 33 (0x21), while the code was expecting it to be 0x00 .. 0x1F.
https://github.com/torvalds/linux/blob/v5.17-rc8/drivers/hwmon/k10temp.c#L432-L453 agrees.
I'm not sure if other ranges listed here should also be accepted.

I noticed this while implementing CPU model detection for halide.

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lebedev.ri created this revision.Mar 15 2022, 8:32 AM
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This revision is now accepted and ready to land.Mar 15 2022, 8:34 AM
This revision was landed with ongoing or failed builds.Mar 15 2022, 10:29 AM
This revision was automatically updated to reflect the committed changes.