Hi, On Fri, Oct 16, 2020 at 7:01 PM Stephen Boyd <sboyd@xxxxxxxxxx> wrote: > > Quoting Stephen Boyd (2020-10-15 20:16:27) > > Quoting Douglas Anderson (2020-10-14 17:13:29) > > > From: Taniya Das <tdas@xxxxxxxxxxxxxx> > > > > > > In the case where the PLL configuration is lost, then the pm runtime > > > resume will reconfigure before usage. > > > > Taniya, this commit needs a lot more describing than one sentence. I see > > that the PLL's L value is reset at boot, but only once. That seems to be > > because the bootloader I have doesn't set bit 11 for the RETAIN_FF bit > > on the lpass_core_hm_gdsc. Once the gdsc is turned off the first time, > > the PLL settings are lost and the L val is reset to 0. That makes sense > > because RETAIN_FF isn't set. This also means the other register writes > > during probe are lost during the first suspend of the lpass core clk > > controller. Then when the GDSC is turned on the next time for this clk > > controller being runtime resumed we will set the retain bit and then > > configure the PLL again. BTW, I see that runtime PM is called for this > > clk controller for all the clk operations. Maybe there should be some > > auto suspend timeout so that we're not toggling the gdsc constantly? > > > > I hacked up the GDSC code to set the bit at gdsc registration time and > > it seems to fix the problem I'm seeing (i.e. that the PLL is stuck, > > which should also be in the commit text here). When I try to set the bit > > in the bootloader though my kernel won't boot. I guess something is > > hanging the system if I enable the retain bit in the GDSC? > > > > After hacking on this for some time it looks like we can apply this > patch instead and things are good. The first two patches in this series > look mostly good to me minus some nitpicks so please resend. By this you mean the two newlines you mentioned on <https://crrev.com/c/2473610>, right? I think all the rest of your comments were on patch #3 (this patch) which I think we're dropping. I'm happy to repost a v5 of just patches #1 and #2 with the newlines fixed next week, or I'm happy if you want to fix them when applying as you alluded to on the Chrome OS gerrit. Just let me know. I just want to make sure I'm not missing some other nits before I post the v5. ;-) -Doug
