On Thu, 14 Mar 2024 at 08:59, Sudeep Holla <sudeep.holla@xxxxxxx> wrote: > > On Thu, Mar 14, 2024 at 08:52:59AM -0600, Mathieu Poirier wrote: > > On Wed, Mar 13, 2024 at 05:17:56PM +0000, Abdellatif El Khlifi wrote: > > > Hi Mathieu, > > > > > > On Wed, Mar 13, 2024 at 10:25:32AM -0600, Mathieu Poirier wrote: > > > > On Tue, Mar 12, 2024 at 05:32:52PM +0000, Abdellatif El Khlifi wrote: > > > > > Hi Mathieu, > > > > > > > > > > On Tue, Mar 12, 2024 at 10:29:52AM -0600, Mathieu Poirier wrote: > > > > > > > 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). > > > > > > > > > > > > > >From the above I take it that booting with a preloaded firmware is a > > > > > > scenario that needs to be supported and not just a temporary stage. > > > > > > > > > > The current status of the Corstone-1000 SoC requires that there is > > > > > a preloaded firmware for the external core. Preloading is done externally > > > > > either through the FPGA bootloader or the emulator (FVP) before powering > > > > > on the SoC. > > > > > > > > > > > > > Ok > > > > > > > > > Corstone-1000 will be upgraded in a way that the A core running Linux is able > > > > > to share memory with the remote core and also being able to access the remote > > > > > core memory so Linux can copy the firmware to. This HW changes are still > > > > > This is why this patchset is relying on a preloaded firmware. And it's the step 1 > > > > > of adding remoteproc support for Corstone. > > > > > > > > > > > > > Ok, so there is a HW problem where A core and M core can't see each other's > > > > memory, preventing the A core from copying the firmware image to the proper > > > > location. > > > > > > > > When the HW is fixed, will there be a need to support scenarios where the > > > > firmware image has been preloaded into memory? > > > > > > No, this scenario won't apply when we get the HW upgrade. No need for an > > > external entity anymore. The firmware(s) will all be files in the linux filesystem. > > > > > > > Very well. I am willing to continue with this driver but it does so little that > > I wonder if it wouldn't simply be better to move forward with upstreaming when > > the HW is fixed. The choice is yours. > > > > I think Robin has raised few points that need clarification. I think it was > done as part of DT binding patch. I share those concerns and I wanted to > reaching to the same concerns by starting the questions I asked on corstone > device tree changes. > I also agree with Robin's point of view. Proceeding with an initial driver with minimal functionality doesn't preclude having complete bindings. But that said and as I pointed out, it might be better to wait for the HW to be fixed before moving forward. > -- > Regards, > Sudeep
