Hi Krzysztof, On Thu, Mar 14, 2024 at 02:56:53PM +0100, Krzysztof Kozlowski wrote: > On 14/03/2024 14:49, Abdellatif El Khlifi wrote: > >> Frankly at the moment I'd be inclined to say it isn't even a remoteproc > >> binding (or driver) at all, it's a reset controller. Bindings are a contract > >> for describing the hardware, not the current state of Linux driver support - > >> if this thing still needs mailboxes, shared memory, a reset vector register, > >> or whatever else to actually be useful, those should be in the binding from > >> day 1 so that a) people can write and deploy correct DTs now, such that > >> functionality becomes available on their systems as soon as driver support > >> catches up, and b) the community has any hope of being able to review > >> whether the binding is appropriately designed and specified for the purpose > >> it intends to serve. > > > > This is an initial patchset for allowing to turn on and off the remote processor. > > The FW is already loaded before the Corstone-1000 SoC is powered on and this > > is done through the FPGA board bootloader in case of the FPGA target. > > Or by the Corstone-1000 FVP model (emulator). > > > > The plan for the driver is as follows: > > > > Step 1: provide a foundation driver capable of turning the core on/off > > Step 2: provide mailbox support for comms > > Step 3: provide FW reload capability > > > > Steps 2 & 3 are waiting for a HW update so the Cortex-A35 (running Linux) can > > share memory with the remote core. > > > > So, when memory sharing becomes available in the FPGA and FVP the > > DT binding will be upgraded with: > > > > - mboxes property specifying the RX/TX mailboxes (based on MHU v2) > > - memory-region property describing the virtio vrings > > > > Currently the mailbox controller does exist in the HW but is not > > usable via virtio (no memory sharing available). > > > > Do you recommend I add the mboxes property even currently we can't do the comms ? > > Bindings should be complete, regardless whether Linux driver supports it > or not. Please see writing bindings document for explanation on this and > other rules. > > So yes: please describe as much as possible/reasonable. I'll do thanks. Cheers, Abdellatif
