On Fri, Oct 18, 2024 at 06:13:05PM -0500, Bjorn Helgaas wrote: > On Tue, Oct 15, 2024 at 04:33:25PM +0800, Richard Zhu wrote: > > Previous reference clock of i.MX95 PCIe RC is on when system boot to > > kernel. But boot firmware change the behavor, it is off when boot. So it > > needs be turn on when it is used. Also it needs be turn off/on when suspend > > and resume. > > I think this background would make more sense in patch 2. IIUC, > that's where the driver behavior changes to do something with the > "ref" clock. > > I'm not sure how to interpret "Previous reference clock of i.MX95 PCIe > RC is on when system boot to kernel. But boot firmware change the > behavor, it is off when boot." > > Does that mean a previous version of the boot firmware left the ref > clock on at handoff to the OS, and newer firmware turns it off? If > so, I think it would be useful to include information about the > relevant firmware versions. > Most likely that the bootloader *used to* turn on the reference clock and now it decides not to do so (for whatever reason). But ideally, the clock should be voted/enabled by the kernel irrespective of that. So the reference of 'boot firmware' is not relevant here. - Mani -- மணிவண்ணன் சதாசிவம்