Re: [PATCH 1/4] dt-bindings: remoteproc: imx_rproc: Add "rpmsg" subnode support

[Rob Herring]

On Wed, Aug 27, 2025 at 02:49:54PM +0000, Shenwei Wang wrote:
> 
> 
> > -----Original Message-----
> > From: Rob Herring <robh@xxxxxxxxxx>
> > Sent: Tuesday, August 26, 2025 3:09 PM
> > To: Shenwei Wang <shenwei.wang@xxxxxxx>
> > Cc: Bjorn Andersson <andersson@xxxxxxxxxx>; Mathieu Poirier
> > <mathieu.poirier@xxxxxxxxxx>; Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>; Conor
> > Dooley <conor+dt@xxxxxxxxxx>; Shawn Guo <shawnguo@xxxxxxxxxx>; Sascha
> > Hauer <s.hauer@xxxxxxxxxxxxxx>; Linus Walleij <linus.walleij@xxxxxxxxxx>;
> > Bartosz Golaszewski <brgl@xxxxxxxx>; Pengutronix Kernel Team
> > <kernel@xxxxxxxxxxxxxx>; Fabio Estevam <festevam@xxxxxxxxx>; Peng Fan
> > <peng.fan@xxxxxxx>; linux-remoteproc@xxxxxxxxxxxxxxx;
> > devicetree@xxxxxxxxxxxxxxx; imx@xxxxxxxxxxxxxxx; linux-arm-
> > kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; dl-linux-imx <linux-
> > imx@xxxxxxx>
> > Subject: [EXT] Re: [PATCH 1/4] dt-bindings: remoteproc: imx_rproc: Add "rpmsg"
> > subnode support
> > > Each subnode within "rpmsg" represents an individual RPMSG channel.
> > > The name of each subnode corresponds to the channel name as defined by
> > > the remote processor.
> > >
> > > All remote devices associated with a given channel are defined as
> > > child nodes under the corresponding channel node.
> > 
> > How is each channel addressed? Are they really grouped by type first (i2c, gpio,
> > etc.) then an address within the group? Or is there some flat channel numbering?
> > If the latter, then the addresses in the DT shoulc match the channel number.
> > 
> 
> Yes, the channels are grouped by type and identified by unique channel names assigned 
> by the remote processor.
> 
> The RPMSG bus dynamically assigns addresses to each channel at runtime. Because these 
> addresses are not static, they cannot be pre-defined in the dts.

But you did define addresses. How do you know which channel 'gpio@1' 
corresponds to if RPMSG dynamically assigns addresses?

Rob