On Mon, Jan 04, 2021 at 02:42:08PM +0000, Suzuki K Poulose wrote: > Hi Rob, > > On 1/3/21 5:02 PM, Rob Herring wrote: > > On Wed, Dec 23, 2020 at 03:33:38PM +0530, Anshuman Khandual wrote: > > > From: Suzuki K Poulose <suzuki.poulose@xxxxxxx> > > > > > > Document the device tree bindings for Embedded Trace Extensions. > > > ETE can be connected to legacy coresight components and thus > > > could optionally contain a connection graph as described by > > > the CoreSight bindings. > > > > > > Cc: devicetree@xxxxxxxxxxxxxxx > > > Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> > > > Cc: Mike Leach <mike.leach@xxxxxxxxxx> > > > Cc: Rob Herring <robh@xxxxxxxxxx> > > > Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> > > > Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> > > > --- > > > Documentation/devicetree/bindings/arm/ete.txt | 41 +++++++++++++++++++++++++++ > > > 1 file changed, 41 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/arm/ete.txt > > > > Bindings are in schema format now, please convert this. > > > > Sure, will do that. > > > > > > > diff --git a/Documentation/devicetree/bindings/arm/ete.txt b/Documentation/devicetree/bindings/arm/ete.txt > > > new file mode 100644 > > > index 0000000..b52b507 > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/arm/ete.txt > > > @@ -0,0 +1,41 @@ > > > +Arm Embedded Trace Extensions > > > + > > > +Arm Embedded Trace Extensions (ETE) is a per CPU trace component that > > > +allows tracing the CPU execution. It overlaps with the CoreSight ETMv4 > > > +architecture and has extended support for future architecture changes. > > > +The trace generated by the ETE could be stored via legacy CoreSight > > > +components (e.g, TMC-ETR) or other means (e.g, using a per CPU buffer > > > +Arm Trace Buffer Extension (TRBE)). Since the ETE can be connected to > > > +legacy CoreSight components, a node must be listed per instance, along > > > +with any optional connection graph as per the coresight bindings. > > > +See bindings/arm/coresight.txt. > > > + > > > +** ETE Required properties: > > > + > > > +- compatible : should be one of: > > > + "arm,embedded-trace-extensions" > > > + > > > +- cpu : the CPU phandle this ETE belongs to. > > > > If this is 1:1 with CPUs, then perhaps it should be a child node of the > > CPU nodes. > > Yes, it is 1:1 with the CPUs. I have tried to keep this aligned with that of > "coresight-etm4x". The same driver handles both. The only reason why this > was separated from the "coresight.txt" is to describe the new configurations > possible (read, TRBE). Would it be possible to keep the CPU handle rather than moving things under the CPU nodes? ETMv3.x and ETMv4.x are using a handle and as Suzuki points out ETE and ETMv4.x are sharing the same driver. Proceeding differently for the ETE would be terribly confusing. > > That said, I am happy to move this under the CPU, if Mathieu is happy with > the diversion. > > Thanks for the review. > > Suzuki
