AMD-Powered Lenovo ThinkPads To Soon Have Working Platform Profile Support On Linux
Last month I covered the issue of Lenovo's ACPI Platform Profile support for AMD-powered laptops was busted on Linux. The platform profile controls were exposed but in reality did not work. Fortunately, fixed up support for this feature is now on the way to the Linux kernel for letting users choose between better performance or extended battery life and cooler operating device.
Confirmed in my own tests and discovered independently by Lenovo as well is that the ACPI platform profile support for their ThinkPad laptops on Linux didn't actually work. Choosing between the performance / balanced / power saver modes did not impact the performance/power unlike this functionality with their Intel-powered ThinkPads.
Last month this broken support was disabled in the mainline Linux kernel while now proper support is on the way, likely for the v5.18 kernel. Under review is adding PSC mode support to the ThinkPad ACPI Linux driver as needed for platform profile support on AMD laptops. The PSC mode is properly handled where as previously only the MMC mode used by Intel was supported and taking that code path broke for AMD Ryzen systems.
Thus once that patch makes it to the mainline kernel, the platform profile support should be working on AMD Ryzen powered Lenovo laptops for switching between performance and power-savings preferences.
For improving ACPI Platform Profile support in general, Lenovo is also proposing support for switching between Platform Profiles in an easier manner whether on AC (wall charging) or DC (battery) modes. Lenovo laptops at least can easily switch platform profiles based on power mode and so under a "request for comments" was providing an implementation that allows for easily setting the platform profile preference depending upon power source.
Confirmed in my own tests and discovered independently by Lenovo as well is that the ACPI platform profile support for their ThinkPad laptops on Linux didn't actually work. Choosing between the performance / balanced / power saver modes did not impact the performance/power unlike this functionality with their Intel-powered ThinkPads.
Last month this broken support was disabled in the mainline Linux kernel while now proper support is on the way, likely for the v5.18 kernel. Under review is adding PSC mode support to the ThinkPad ACPI Linux driver as needed for platform profile support on AMD laptops. The PSC mode is properly handled where as previously only the MMC mode used by Intel was supported and taking that code path broke for AMD Ryzen systems.
Thus once that patch makes it to the mainline kernel, the platform profile support should be working on AMD Ryzen powered Lenovo laptops for switching between performance and power-savings preferences.
The ThinkPad T14s Gen2a with Ryzen 7 PRO 5850U running Linux well.
For improving ACPI Platform Profile support in general, Lenovo is also proposing support for switching between Platform Profiles in an easier manner whether on AC (wall charging) or DC (battery) modes. Lenovo laptops at least can easily switch platform profiles based on power mode and so under a "request for comments" was providing an implementation that allows for easily setting the platform profile preference depending upon power source.
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