On Tue 08 Jun 17:29 CDT 2021, Stephen Boyd wrote: > Quoting Bjorn Andersson (2021-06-08 15:26:23) > > On Tue 08 Jun 17:15 CDT 2021, Stephen Boyd wrote: > > > > > Quoting Bjorn Andersson (2021-06-07 16:31:47) > > > > On Mon 07 Jun 12:48 CDT 2021, khsieh@xxxxxxxxxxxxxx wrote: > > > > > > > > > Sorry about the confusion. What I meant is that even though DP controller is > > > > > in the MDSS_GDSC > > > > > power domain, DP PHY/PLL sources out of CX. The DP link clocks have a direct > > > > > impact > > > > > on the CX voltage corners. Therefore, we need to mention the CX power domain > > > > > here. And, since > > > > > we can associate only one OPP table with one device, we picked the DP link > > > > > clock over other > > > > > clocks. > > > > > > > > Thank you, that's a much more useful answer. > > > > > > > > Naturally I would think it would make more sense for the PHY/PLL driver > > > > to ensure that CX is appropriately voted for then, but I think that > > > > would result in it being the clock driver performing such vote and I'm > > > > unsure how the opp table for that would look. > > > > > > > > @Stephen, what do you say? > > > > > > > > > > Wouldn't the PHY be the one that sets some vote? So it wouldn't be the > > > clk driver, and probably not from the clk ops, but instead come from the > > > phy ops via phy_enable() and phy_configure(). > > > > > > > If I understand the logic correctly *_configure_dp_phy() will both > > configure the vco clock and "request" the clock framework to change the > > rate. > > > > So I presume what you're suggesting is that that would be the place to > > cast the CX corner vote? > > Yes that would be a place to make the CX vote. The problem is then I > don't know where to drop the vote. Is that when the phy is disabled? We do pass qcom_qmp_phy_power_off() and power down the DP part as DP output is being disabled. So that sounds like a reasonable place to drop the vote for the lowest performance state. Regards, Bjorn
