On 01/13/20 12:56, Ni, Ray wrote: > We shouldn't assume that a DriverBindingStart() can only start on a handle > with device path installed. DevicePath protocol is just a special protocol. > It's possible that a bus driver starts on a host controller handle and > creates multiple children, each with only a Specific_IO protocol installed. > Certain device driver can start on the children handle and open the > Specific_IO protocol BY_DRIVER. > I am not sure if certain today's network drivers may work like this. It's > allowed per UEFI spec.
I agree. Under "10.2 EFI Device Path Protocol", the spec says, "If the handle does not logically map to a physical device, the handle may not necessarily support the device path protocol." I think gBS->ConnectController() and EFI_DRIVER_BINDING_PROTOCOL.Supported() should work on such handles. If we'd like to work around related issues in drivers, then I'd suggest new command line options for the "load", "connect", "reconnect" shell commands (maybe more), for filtering out handles that do not carry device paths. Such command line options could be added as an extension, IIUC, such as "-_option". I.e., I believe it's not necessary to start with UEFI Shell Spec updates. Thanks Laszlo -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#53194): https://edk2.groups.io/g/devel/message/53194 Mute This Topic: https://groups.io/mt/69653841/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
