On Thu, Jan 28, 2021 at 9:45 PM Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> wrote: > > On 28/01/2021 22:26, Rob Herring wrote: > > On Thu, Jan 28, 2021 at 11:52 AM Dmitry Baryshkov > > <dmitry.baryshkov@xxxxxxxxxx> wrote: > >> > >> Some Qualcomm platforms require to power up an external device before > >> probing the PCI bus. E.g. on RB5 platform the QCA6390 WiFi/BT chip needs > >> to be powered up before PCIe0 bus is probed. Add a quirk to the > >> respective PCIe root bridge to attach to the power domain if one is > >> required, so that the QCA chip is started before scanning the PCIe bus. > > > > This is solving a generic problem in a specific driver. It needs to be > > solved for any PCI host and any device. > > Ack. I see your point here. > > As this would require porting code from powerpc/spark of-pci code and > changing pcie port driver to apply power supply before bus probing > happens, I'd also ask for the comments from PCI maintainers. Will that > solution be acceptable to you? Oh good, something exists. :) FYI, there's another similar case needing this that just popped up[1]. Rob [1] https://lore.kernel.org/linux-pci/20210129173057.30288c9d@xxxxxxxx/