On Sun Sep 27, 2026 at 8:14 PM JST, Alexandre Courbot wrote: > The upcoming r000 firmware support [1] introduces a new type of command > named GMC alongside the existing and already supported RPC command type. > > Since RPC was the only command type supported so far, it was embedded > into the lowest command queue level: the message header actually > includes the RPC header and the code considers them as one. > > This makes the r000/GMC support difficult to land without a refactor, > with the result of transport layer code being duplicated between the two > message types, and no clear separation between the RPC and GMC code > which are mixed together in the command queue. Merging the code that way > would introduce quite some technical debt. > > Thus, this series prepares a proper landing ground for a new message > type by extracting all the RPC layer code and moving it into its own > sub-modules, making the `cmdq` module completely agnostic of the type of > message it transports. By the end of the series, the only mention of RPC > in `cmdq.rs` is for the `rpc` sub-module. > > With the transport and message layers properly separated, support for > GMC can be added into sibling modules of `rpc`, and the transport layer > can be converted once when doing the switch to r000. > > This moves quite a bit of code around, but most of it is moved verbatim. > No significant functional change is intended. > > For the r000 series, this essentially means the following: > > - Its patch 7 making `allocate_command` generic can be dropped as the > transport layer makes no assumption about the message type. > - Patches adding GMC support will do it in dedicated `gmc` sub-modules, > following the model set by RPC. These `gmc` sub-modules will start as > `dead_code` as they are being built. > - The "switch to r000" patch will essentially operate on the transport > layer level, i.e. `cmdq.rs`. > - There should be no need for extra post-switch RPC fixing, as the > transport layer code will already be shared with GMC. > > Overall, this should make the r000 series much easier to review and > eventually land, while not creating new technical debt. > > This series is based on `drm-rust-next`.
Sashiko has found a couple of serious issues, and I've found another I had overlooked, so please ignore this revision. I will send v2 shortly.
