On Sat, Jul 24, 2021 at 10:49 PM David E. Box <david.e.box@xxxxxxxxxxxxxxx> wrote: > On Sat, 2021-07-24 at 11:29 +0300, Andy Shevchenko wrote: > > On Friday, July 23, 2021, Michael Bottini > > <michael.a.bottini@xxxxxxxxxxxxxxx> wrote: > > > Tiger Lake devices have the capability to track the duration > > > of time that their Power Supply Units (PSUs) are turned off during > > > S0ix. > > > This patch adds a debugfs file `pson_residency_usec` to provide > > > access to this counter. > > > > > > In order to determine whether the device is capable of PSON, > > > use acpi_init_properties() to reevaluate _DSD. > > > > > > > > > > It’s direct abuse of ACPI specification as I read it: > > > > “_DSD must return the same data each time it is evaluated. Firmware > > should not expect it to be evaluated every time (in case it is > > implemented as a method).” > > > > > > NAK to the series. > > Okay, we'll check with the BIOS folks. They are setting this property > from _STA. They may not expect OSPM to reevaluate _DSD. Does it matter? > But they may > have expected that OSPM doesn't attempt to read _DSD until after _STA > is executed. They may study a bit of ACPI specification perhaps? Or if there is indeed an issue with the specification language (so native-speaking people misinterpret above) then ECR to ASWG should be submitted? -- With Best Regards, Andy Shevchenko
