[Public] > On 2/25/22 17:04, Limonciello, Mario wrote: > > [Public] > > > >> On Fri, Feb 25, 2022 at 12:11:11AM -0600, Mario Limonciello wrote: > >>> This board definition was originally created for mobile devices to > >>> designate default link power managmeent policy to influence runtime > >>> power consumption. > >>> > >>> As this is interesting for more than just mobile designs, rename the > >>> board to `board_ahci_low_power` to make it clear it is about default > >>> policy. > >> > >> Is there any good reason to not just apply the policy to all devices > >> by default? > > > > That sure would make this all cleaner. > > > > I think Hans knows more of the history here than anyone else. I had > > presumed there was some data loss scenarios with some of the older > > chipsets. > > When I first introduced this change there were reports of crashes and > data corruption caused by setting the policy to min_power, these were > tied to some motherboards and/or to some drives. > > This is the whole reason why I only enabled this on a subset of all the > AHCI chipsets. > > At least on devices with a chipset which is currently marked as > mobile, the motherboard specific issues could be fixed with a BIOS > update. But I doubt that similar BIOS fixes have also been rolled > out to all desktop boards (and have been applied by all users), > and I also don't know about older boards. > > So enabling this on all chipsets is definitely not without risks. > This was before min_power_with_partial and min_power_with_dipm were introduced though right? Maybe another way to look at this is to drop the policy min_power, which overall is dangerous.
