On Tue, Oct 11, 2022 at 04:46:53PM +0300, Dmitry Baryshkov wrote: > On 11/10/2022 16:14, Johan Hovold wrote: > > The power-down delay was included in the first version of the QMP driver > > as an optional delay after powering on the PHY (using > > POWER_DOWN_CONTROL) and just before starting it. Later changes modified > > this sequence by powering on before initialising the PHY, but the > > optional delay stayed where it was (i.e. before starting the PHY). > > > > The vendor driver does not use a delay before starting the PHY and this > > is likely not needed on any platform unless there is a corresponding > > delay in the vendor kernel init sequence tables (i.e. in devicetree). > > > > Let's keep the delay for now, but drop the redundant delay period > > configuration while increasing the unnecessarily low timer slack > > somewhat. > > Actually, the vendor driver does this 995..1005 sleep. But contrary to > our driver it does that after programming whole PHY init sequence, which > includes SW_RESET / START_CTL, but before programming the pipe clocks. Right, it does it after starting the PHY which means that you don't have to poll for as long for the PHY status. It's a different delay entirely. > I think we can either drop this delay completely, or move it before > read_poll_timeout(). It definitely shouldn't be used for any new platforms, but I opted for the conservative route of keeping it in case some of the older platforms actually do need it. My bet is that this is all copy-paste cruft that could be removed, but I'd rather do that as a separate follow-on change. Perhaps after testing some more SoC after removing the delay. SC8280XP certainly doesn't need it. Johan
