On Fri, Feb 09, 2024 at 12:02:48PM +0100, Daniel Vetter wrote: > On Thu, Feb 08, 2024 at 04:27:02PM +0100, Maxime Ripard wrote: > > On Wed, Feb 07, 2024 at 10:35:49AM +0100, Daniel Vetter wrote: > > > On Wed, Feb 07, 2024 at 01:27:59AM +0800, Sui Jingfeng wrote: > > > > The component helper functions are the glue, which is used to bind multiple > > > > GPU cores to a virtual master platform device. Which is fine and works well > > > > for the SoCs who contains multiple GPU cores. > > > > > > > > The problem is that usperspace programs (such as X server and Mesa) will > > > > search the PCIe device to use if it is exist. In other words, usperspace > > > > programs open the PCIe device with higher priority. Creating a virtual > > > > master platform device for PCI(e) GPUs is unnecessary, as the PCI device > > > > has been created by the time drm/etnaviv is loaded. > > > > > > > > we create virtual platform devices as a representation for the vivante GPU > > > > ip core. As all of subcomponent are attached via the PCIe master device, > > > > we reflect this hardware layout by binding all of the virtual child to the > > > > the real master. > > > > > > > > Signed-off-by: Sui Jingfeng <sui.jingfeng@xxxxxxxxx> > > > > > > Uh so my understanding is that drivers really shouldn't create platform > > > devices of their own. For this case here I think the aux-bus framework is > > > the right thing to use. Alternatively would be some infrastructure where > > > you feed a DT tree to driver core or pci subsystem and it instantiates it > > > all for you correctly, and especially with hotunplug all done right since > > > this is pci now, not actually part of the soc that cannot be hotunplugged. > > > > I don't think we need intermediate platform devices at all. We just need > > to register our GPU against the PCI device and that's it. We don't need > > a platform device, we don't need the component framework. > > Afaik that's what this series does. The component stuff is for the > internal structure of the gpu ip, so that the same modular approach that > works for arm-soc also works for pci chips. But there should be a single PCI device, while we have multiple "DT" devices, right? Or is there several PCI devices too on that PCI card? Maxime
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