On Tue, Feb 14, 2023 at 01:12:25PM +0100, Vincent Whitchurch wrote: > On Mon, Feb 13, 2023 at 06:54:49PM +0100, Johannes Berg wrote: > > On Fri, 2023-01-27 at 15:30 +0100, Vincent Whitchurch wrote: > > > My first approach to getting platform drivers working on UML was by > > > adding a minimal PCI-to-platform bridge driver, which worked without > > > modifications to virt-pci, but that got shot down: > > > > > > https://lore.kernel.org/lkml/20230120-simple-mfd-pci-v1-1-c46b3d6601ef@xxxxxxxx/ > > > > Reading through that ... OK that isn't fun either :-) > > > > Sounds like there's a use case for something else though, but the PCI > > IDs issue also makes that thorny. > > Yes, Greg was initially totally opposed to the idea of putting platform > devices under PCI devices, but in his latest email he seemed to > allow it in some cases. It's still unclear if he'd be OK with a > "virtual PCI-to-platform bridge" though. And yes, adding platform > devices support like in this patch removes one layer and also eliminates > the disadvantage of having to wait for user space to specify a PCI ID > for the bridge device. Like I said in that thread, we have multiple usecases needing something similar for non-discoverable MMIO devices behind a PCI device. And I convinced Greg a platform device was okay, so please continue that path. I'm adding you to the thread of other usecases. Rob
