Hi Krzysztof, On 6/23/21 3:53 PM, Krzysztof Wilczyński wrote: > [+cc Sasha for visibility] > > Hi Michal, > > Thank you for sending v2 so promptly! And for all the extra changes and > fixes. Much appreciated! > >> Enable PCIE reference clock. There is no remove function that's why >> this should be enough for simple operation. >> Normally this clock is enabled by default by firmware but there are >> usecases where this clock should be enabled by driver itself. >> It is also good that clock user is recorded in clock framework. > > Small nitpicks: it would be PCIe here in the above and in the error > message (this is as per [1]), and "use cases" also in the above. > > This can be corrected when the patch will be merged by either Bjorn or > Lorenzo, to avoid sending v3 unnecessarily, provided that they would > have a moment to do it, of course. Ok. Will wait for them. > >> Fixes: ab597d35ef11 ("PCI: xilinx-nwl: Add support for Xilinx NWL PCIe Host Controller") > > Thank you! > > Does it make sense for this change to be back-ported to stable and > long-term kernels? > > I am asking to make sure we do the right thing here, as I can imagine > that older kernels (primarily because some folks could use, for example, > Ubuntu LTS releases for development) might often be used by people who > work with the Xilinx FPGAs and such. I think that make sense to do so. I haven't had a time to take look at it closely but I think on Xilinx ZynqMP zcu102 board this missing patch is causing hang when standard debian 5.10 is used. > > [...] >> + err = clk_prepare_enable(pcie->clk); >> + if (err) { >> + dev_err(dev, "can't enable pcie ref clock\n"); >> + return err; >> + } >> + > > As per the nitpick above, it would be "PCIe", but probably no need to > send v3 to correct this. I will keep my eyes on it and will update it if v3 is required. Thanks, Michal