Hi Rob,
On 14/06/18 14:59, Rob Herring wrote:
On Thu, Jun 14, 2018 at 2:53 AM, Suzuki K Poulose Suzuki.Poulose@arm.com wrote:
On 13/06/18 22:07, Matt Sealey wrote:
-----Original Message----- From: Mathieu Poirier mathieu.poirier@linaro.org
So, if the suggestion is to use an existing property "unit", I am fine with it, if people agree to it.
If we're going to have something sharply different than ACPI I prefer Rob's idea.
No, the above comment is about using "unit" ( if it is a standard property for specifying something specific to hardware) instead of "coresight,hwid". I would prefer to stick to the DT graph bindings, because :
"unit" is not a standard property and I don't like it either.
- The connections are bi-directional => Well, not necessarily
bi-directional in terms of the data flow. But the connection information is critical. i.e, we need information about both the end-points of a connection, which the DT graph bindings solves.
All we are missing is a way for specifying the "hardware port" number and the direction of flow. I don't see why do we need to create something new just for these two properties for something that exists today and works reasonably well for the usecase.
If you have "in-ports" and "out-ports" nodes, then that gives you direction and you can use reg for the "hardware port".
in-ports { port@0 { reg = <0>; endpoint {...}; }; port@1 { reg = <1>; endpoint {...}; }; }; out-ports { port@0 { reg = <0>; endpoint {...}; }; };
I'll need to check, but dtc may need an update to not warn about this.
I did a quick check with the upstream dtc tool and the above form is doesn't generate any errors.
Mathieu, Rob,
Shall I proceed with the proposal above ?
Suzuki