Fan and power improvements

[jackpot51]

• Re-enable interpolation, which was found to be important when reviewing Thomas' improved fan curve #550
• Fix power.sh script, used for debugging fan curve: scripts: Fix ectool commands in power script #559
• Configurable power levels (PL1, PL2, and TCC) - potentially exposed via /sys/firmware/acpi/platform_profile
• Configurable fan curves (either with baked-in quiet, balanced, cool options or exposing point configuration to the OS)

[higher972]

As a lemp13-b user, I would be incredibly grateful for the "Configurable fan curves" option. Any task with a constant low/medium load causes the fan to repeatedly cut on and off, and can be rather distracting. Ideally, one curve could provide a constant low/medium fan speed in response to a constant low/medium load. (Or allow the easy configuration of such a curve.)

The current curve is fantastic for when the system is mostly idle. But the inability to manage fan noise in other cases (without recompiling the firmware) is the one thing that makes me hesitant to recommend the Lemur Pro to others.

[ Edit: I noticed that NovaCustom solved the fan on-off-on-off issue by simply keeping the fan on at low levels when idle. Something analogous to their "Silent" and "Performance" curves seem ideal and worth considering: https://docs.dasharo.com/unified/novacustom/features/#fan-profiles ]

[crawfxrd]

CPU power levels

• PL1,PL2,PL4
  • Kernel driver support
  • Configurable from sysfs
  • Configure initial values in coreboot
• TCC
  • Kernel driver support (intel_tcc_cooling)
  • No sysfs support
  • Configure initial value in coreboot
    • MSR may be locked (default on PTL+); check TccOffsetLock

Does anything currently use these drivers or modify the values at run-time?

Fan control mode

• Only have "auto" (EC controlled) and "manual" (host controlled)
  • Remove PWM/RPM mode distinction
• Host control will only use 0-100 percent value
  • EC will be responsible for converting percent to PWM/RPM duty value
  • Change existing PWM reporting to percentage
• Do we need to write OS drivers for host control?

Fan profiles

• For auto control mode
• 3 options: Balanced, Quiet, Performance
  • "Custom" option to avoid writing OS drivers?
• Fixed number of fan points in tables?
  • 10 to match proprietary firmware

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ACPI

• Implement proper Fan Device support? (11.3 Fan Device)