The FADT contains a flag `ACPI_FADT_PLATFORM_CLOCK` telling the OSPM if
a specification-compliant PM Timer is present. Currently, this flag is
set regardless of the timer being enabled or disabled.
To be specification-compliant, only set that flag, when the hardware PM
Timer is enabled. This changes behaviour of all mainboards defaulting to
USE_PM_ACPI_TIMER=n.
Note: On platforms supporting uCode PM ACPI Timer emulation, this is
required, too, because emulation does not support `TMR_STS`. Any
OS or software checking this flag and thus relying on the overflow
flag would not work (properly).
Change-Id: Id2e5d69b5515c21e6ce922dab2cb88b494c65ebe
Signed-off-by: Michael Niewöhner <foss@mniewoehner.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57934
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
5c259642c2