On Mon, Oct 19, 2020 at 02:54:11PM +0530, Viresh Kumar wrote: > On 19-10-20, 10:17, Sudeep Holla wrote: > > On Mon, Oct 19, 2020 at 10:28:27AM +0530, Viresh Kumar wrote: > > > On 16-10-20, 12:12, Sudeep Holla wrote: > > > > On Fri, Oct 16, 2020 at 07:00:21AM +0100, Sudeep Holla wrote: > > > > > On Fri, Oct 16, 2020 at 09:54:34AM +0530, Viresh Kumar wrote: > > > > > > On 15-10-20, 19:05, Sudeep Holla wrote: > > > > > > > OK, this breaks with SCMI which doesn't provide clocks but manage OPPs > > > > > > > directly. Before this change clk_get(dev..) was allowed to fail and > > > > > > > --EPROBE_DEFER was not an error. > > > > > > > > > > > > I think the change in itself is fine. We should be returning from > > > > > > there if we get EPROBE_DEFER. The question is rather why are you > > > > > > getting EPROBE_DEFER here ? > > > > > > > > > > > > > > > > Ah OK, I didn't spend too much time, saw -EPROBE_DEFER, just reverted > > > > > this patch and it worked. I need to check it in detail yet. > > > > > > > > > > > > > You confused me earlier. As I said there will be no clock provider > > > > registered for SCMI CPU/Dev DVFS. > > > > opp_table->clk = clk_get(dev, NULL); > > > > will always return -EPROBE_DEFER as there is no clock provider for dev. > > > > But this change now propagates that error to caller of dev_pm_opp_add > > > > which means we can't add opp to a device if there are no clock providers. > > > > This breaks for DVFS which don't operate separately with clocks and > > > > regulators. > > > > > > The CPUs DT node shouldn't have a clock property in such a case and I > > > would expect an error instead of EPROBE_DEFER then. Isn't it ? > > > > Ideally yes, but for legacy reasons clocks property has been used for > > providing OPP/DVFS handle too. While we can change and add new property > > for that, it will still break old bindings. > > I am not sure I understood it all. So does your platform have the > clock-names property or not for the CPUs ? And how will something > break here ? > Yes it has clocks property but used by SCMI(for CPUFreq/DevFreq) and not by any clock provider driver. E.g. the issue you will see if "clocks" property is used instead of "qcom,freq-domain" on Qcom parts. On SCMI, we have used clocks property to represent perf domain which I understand is not ideal but it is there 🙁. -- Regards, Sudeep
