Alder Lake and hwpstate_intel (RELENG_14)

From: mike tancsa <mike_at_sentex.net>
Date: Fri, 22 Mar 2024 16:42:07 UTC
I have a N100 based industrial PC that is showing some odd cpu frequency 
behaviour on FreeBSD. Linux doesnt seem to show it.

When I boot up the PC, it seems to idle at full speed for a short time 
but then scales *down* to 400 after I add load and stays down at 402. 
Its almost like its backwards ?


I tried setting

dev.hwpstate_intel.[x].epp

to zero, and it doesnt seem to make a difference.

Temp is nice and low as I put a fan on it as well.

  # sysctl -a dev.cpu | grep tempera
dev.cpu.3.temperature: 26.0C
dev.cpu.2.temperature: 26.0C
dev.cpu.1.temperature: 26.0C
dev.cpu.0.temperature: 26.0C

#  sysctl -a dev.cpu | grep freq
dev.cpu.3.freq_levels: 806/-1
dev.cpu.3.freq: 402
dev.cpu.2.freq_levels: 806/-1
dev.cpu.2.freq: 402
dev.cpu.1.freq_levels: 806/-1
dev.cpu.1.freq: 402
dev.cpu.0.freq_levels: 806/-1
dev.cpu.0.freq: 402

dmesg shows I think the ecore vs pcore ?

VT(vga): resolution 640x480
CPU microcode: updated from 0xe to 0x15
CPU: Intel(R) N100 (806.40-MHz K8-class CPU)
   Origin="GenuineIntel"  Id=0xb06e0  Family=0x6  Model=0xbe Stepping=0
Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
Features2=0x7ffafbbf<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,EST,TM2,SSSE3,SDBG,FMA,CX16,xTPR,PDCM,PCID,SSE4.1,SSE4.2,x2APIC,MOVBE,POPCNT,TSCDLT,AESNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND>
   AMD Features=0x2c100800<SYSCALL,NX,Page1GB,RDTSCP,LM>
   AMD Features2=0x121<LAHF,ABM,Prefetch>
   Structured Extended 
Features=0x239ca7eb<FSGSBASE,TSCADJ,BMI1,AVX2,FDPEXC,SMEP,BMI2,ERMS,INVPCID,NFPUSG,PQE,RDSEED,ADX,SMAP,CLFLUSHOPT,CLWB,PROCTRACE,SHA>
   Structured Extended 
Features2=0x98c007bc<UMIP,PKU,OSPKE,WAITPKG,GFNI,VAES,VPCLMULQDQ,RDPID,MOVDIRI,MOVDIR64B>
   Structured Extended 
Features3=0xfc184410<FSRM,MD_CLEAR,IBT,IBPB,STIBP,L1DFL,ARCH_CAP,CORE_CAP,SSBD>
   XSAVE Features=0xf<XSAVEOPT,XSAVEC,XINUSE,XSAVES>
IA32_ARCH_CAPS=0x1580fd6b<RDCL_NO,IBRS_ALL,SKIP_L1DFL_VME,MDS_NO,TAA_NO>
   VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID,VID,PostIntr
   TSC: P-state invariant, performance statistics
real memory  = 8589934592 (8192 MB)
avail memory = 7994687488 (7624 MB)

sett
  sysctl -w debug.cpufreq.verbose=1

shows

cpufreq: get returning immediate freq 402
cpufreq: get returning immediate freq 402
cpufreq: skipping info-only driver cpufreq2
cpufreq: No absolute levels returned by driver
cpufreq: adding abs setting 806 at head
cpufreq: skipping info-only driver cpufreq2
cpufreq: No absolute levels returned by driver
cpufreq: adding abs setting 806 at head
cpufreq: get returning immediate freq 402
cpufreq: get returning immediate freq 402
cpufreq: skipping info-only driver cpufreq1
cpufreq: No absolute levels returned by driver
cpufreq: adding abs setting 806 at head
cpufreq: skipping info-only driver cpufreq1
cpufreq: No absolute levels returned by driver
cpufreq: adding abs setting 806 at head
cpufreq: get returning immediate freq 402
cpufreq: get returning immediate freq 402
cpufreq: skipping info-only driver cpufreq0
cpufreq: No absolute levels returned by driver
cpufreq: adding abs setting 806 at head
cpufreq: skipping info-only driver cpufreq0
cpufreq: No absolute levels returned by driver
cpufreq: adding abs setting 806 at head
cpufreq: get returning immediate freq 402
cpufreq: get returning immediate freq 402


On linux, the CPU looks as follows

  cat /proc/cpuinfo
processor       : 0
vendor_id       : GenuineIntel
cpu family      : 6
model           : 190
model name      : Intel(R) N100
stepping        : 0
microcode       : 0x15
cpu MHz         : 700.000
cache size      : 6144 KB
physical id     : 0
siblings        : 4
core id         : 0
cpu cores       : 4
apicid          : 0
initial apicid  : 0
fpu             : yes
fpu_exception   : yes
cpuid level     : 32
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge 
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe 
syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts 
rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni 
pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr 
pdcm sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx 
f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l2 cdp_l2 ssbd 
ibrs ibpb stibp ibrs_enhanced tpr_shadow flexpriority ept vpid ept_ad 
fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid rdt_a rdseed adx 
smap clflushopt clwb intel_pt sha_ni xsaveopt xsavec xgetbv1 xsaves 
split_lock_detect user_shstk avx_vnni dtherm ida arat pln pts hwp 
hwp_notify hwp_act_window hwp_epp hwp_pkg_req vnmi umip pku ospke 
waitpkg gfni vaes vpclmulqdq rdpid movdiri movdir64b fsrm md_clear 
serialize arch_lbr ibt flush_l1d arch_capabilities
vmx flags       : vnmi preemption_timer posted_intr invvpid ept_x_only 
ept_ad ept_1gb flexpriority apicv tsc_offset vtpr mtf vapic ept vpid 
unrestricted_guest vapic_reg vid ple shadow_vmcs ept_mode_based_exec 
tsc_scaling usr_wait_pause
bugs            : spectre_v1 spectre_v2 spec_store_bypass swapgs
bogomips        : 1612.80
clflush size    : 64
cache_alignment : 64
address sizes   : 39 bits physical, 48 bits virtual
power management:

processor       : 1
vendor_id       : GenuineIntel
cpu family      : 6
model           : 190
model name      : Intel(R) N100
stepping        : 0
microcode       : 0x15
cpu MHz         : 700.000
cache size      : 6144 KB
physical id     : 0
siblings        : 4
core id         : 1
cpu cores       : 4
apicid          : 2
initial apicid  : 2
fpu             : yes
fpu_exception   : yes
cpuid level     : 32
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge 
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe 
syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts 
rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni 
pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr 
pdcm sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx 
f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l2 cdp_l2 ssbd 
ibrs ibpb stibp ibrs_enhanced tpr_shadow flexpriority ept vpid ept_ad 
fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid rdt_a rdseed adx 
smap clflushopt clwb intel_pt sha_ni xsaveopt xsavec xgetbv1 xsaves 
split_lock_detect user_shstk avx_vnni dtherm ida arat pln pts hwp 
hwp_notify hwp_act_window hwp_epp hwp_pkg_req vnmi umip pku ospke 
waitpkg gfni vaes vpclmulqdq rdpid movdiri movdir64b fsrm md_clear 
serialize arch_lbr ibt flush_l1d arch_capabilities
vmx flags       : vnmi preemption_timer posted_intr invvpid ept_x_only 
ept_ad ept_1gb flexpriority apicv tsc_offset vtpr mtf vapic ept vpid 
unrestricted_guest vapic_reg vid ple shadow_vmcs ept_mode_based_exec 
tsc_scaling usr_wait_pause
bugs            : spectre_v1 spectre_v2 spec_store_bypass swapgs
bogomips        : 1612.80
clflush size    : 64
cache_alignment : 64
address sizes   : 39 bits physical, 48 bits virtual
power management:

processor       : 2
vendor_id       : GenuineIntel
cpu family      : 6
model           : 190
model name      : Intel(R) N100
stepping        : 0
microcode       : 0x15
cpu MHz         : 2600.008
cache size      : 6144 KB
physical id     : 0
siblings        : 4
core id         : 2
cpu cores       : 4
apicid          : 4
initial apicid  : 4
fpu             : yes
fpu_exception   : yes
cpuid level     : 32
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge 
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe 
syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts 
rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni 
pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr 
pdcm sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx 
f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l2 cdp_l2 ssbd 
ibrs ibpb stibp ibrs_enhanced tpr_shadow flexpriority ept vpid ept_ad 
fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid rdt_a rdseed adx 
smap clflushopt clwb intel_pt sha_ni xsaveopt xsavec xgetbv1 xsaves 
split_lock_detect user_shstk avx_vnni dtherm ida arat pln pts hwp 
hwp_notify hwp_act_window hwp_epp hwp_pkg_req vnmi umip pku ospke 
waitpkg gfni vaes vpclmulqdq rdpid movdiri movdir64b fsrm md_clear 
serialize arch_lbr ibt flush_l1d arch_capabilities
vmx flags       : vnmi preemption_timer posted_intr invvpid ept_x_only 
ept_ad ept_1gb flexpriority apicv tsc_offset vtpr mtf vapic ept vpid 
unrestricted_guest vapic_reg vid ple shadow_vmcs ept_mode_based_exec 
tsc_scaling usr_wait_pause
bugs            : spectre_v1 spectre_v2 spec_store_bypass swapgs
bogomips        : 1612.80
clflush size    : 64
cache_alignment : 64
address sizes   : 39 bits physical, 48 bits virtual
power management:

processor       : 3
vendor_id       : GenuineIntel
cpu family      : 6
model           : 190
model name      : Intel(R) N100
stepping        : 0
microcode       : 0x15
cpu MHz         : 2597.960
cache size      : 6144 KB
physical id     : 0
siblings        : 4
core id         : 3
cpu cores       : 4
apicid          : 6
initial apicid  : 6
fpu             : yes
fpu_exception   : yes
cpuid level     : 32
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge 
mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe 
syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts 
rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni 
pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr 
pdcm sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave avx 
f16c rdrand lahf_lm abm 3dnowprefetch cpuid_fault epb cat_l2 cdp_l2 ssbd 
ibrs ibpb stibp ibrs_enhanced tpr_shadow flexpriority ept vpid ept_ad 
fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid rdt_a rdseed adx 
smap clflushopt clwb intel_pt sha_ni xsaveopt xsavec xgetbv1 xsaves 
split_lock_detect user_shstk avx_vnni dtherm ida arat pln pts hwp 
hwp_notify hwp_act_window hwp_epp hwp_pkg_req vnmi umip pku ospke 
waitpkg gfni vaes vpclmulqdq rdpid movdiri movdir64b fsrm md_clear 
serialize arch_lbr ibt flush_l1d arch_capabilities
vmx flags       : vnmi preemption_timer posted_intr invvpid ept_x_only 
ept_ad ept_1gb flexpriority apicv tsc_offset vtpr mtf vapic ept vpid 
unrestricted_guest vapic_reg vid ple shadow_vmcs ept_mode_based_exec 
tsc_scaling usr_wait_pause
bugs            : spectre_v1 spectre_v2 spec_store_bypass swapgs
bogomips        : 1612.80
clflush size    : 64
cache_alignment : 64
address sizes   : 39 bits physical, 48 bits virtual
power management:

coretemp0: <CPU On-Die Thermal Sensors> on cpu0
hwpstate_intel0: <Intel Speed Shift> on cpu0
hwpstate_intel1: <Intel Speed Shift> on cpu1
hwpstate_intel2: <Intel Speed Shift> on cpu2
hwpstate_intel3: <Intel Speed Shift> on cpu3
Timecounter "TSC" frequency 806398651 Hz quality 1000