Hi Suzuki, > -----Original Message----- > From: Suzuki K Poulose <suzuki.poulose@xxxxxxx> > Sent: Monday, September 4, 2023 1:57 PM > To: Linu Cherian <lcherian@xxxxxxxxxxx>; mike.leach@xxxxxxxxxx; > james.clark@xxxxxxx; leo.yan@xxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; coresight@xxxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; robh+dt@xxxxxxxxxx; > krzysztof.kozlowski+dt@xxxxxxxxxx; conor+dt@xxxxxxxxxx; > devicetree@xxxxxxxxxxxxxxx; Sunil Kovvuri Goutham > <sgoutham@xxxxxxxxxxx>; George Cherian <gcherian@xxxxxxxxxxx> > Subject: [EXT] Re: [RFC PATCH v3 1/7] dt-bindings: arm: coresight-tmc: Add > "memory-region" property > > External Email > > ---------------------------------------------------------------------- > On 04/09/2023 06:05, Linu Cherian wrote: > > memory-region 0: Reserved trace buffer memory > > > > TMC ETR: When available, use this reserved memory region for > > trace data capture. Same region is used for trace data > > retention after a panic or watchdog reset. > > > > TMC ETF: When available, use this reserved memory region for > > trace data retention synced from internal SRAM after a panic or > > watchdog reset. > > > > memory-region 1: Reserved meta data memory > > > > TMC ETR, ETF: When available, use this memory for register > > snapshot retention synced from hardware registers after a panic > > or watchdog reset. > > Instead of having to use a number to map the memory regions, could we use > > memory-region-names property to describe the index ? That way it is much > easier to read and is less error prone. > > Names could be something like: > > tmc-reserved-trace > tmc-reserved-metadata > Ack. Will use names in the next version. Will take care of the suggestions from Rob. > Suzuki > > > > > Signed-off-by: Linu Cherian <lcherian@xxxxxxxxxxx> > > --- > > .../devicetree/bindings/arm/arm,coresight-tmc.yaml | 13 > +++++++++++++ > > 1 file changed, 13 insertions(+) > > > > diff --git > > a/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml > > b/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml > > index cb8dceaca70e..dce54978554a 100644 > > --- a/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml > > +++ b/Documentation/devicetree/bindings/arm/arm,coresight-tmc.yaml > > @@ -101,6 +101,17 @@ properties: > > and ETF configurations. > > $ref: /schemas/graph.yaml#/properties/port > > > > + memory-region: > > + items: > > + - description: Reserved trace buffer memory for ETR and ETF sinks. > > + For ETR, this reserved memory region is used for trace data capture. > > + Same region is used for trace data retention as well after a panic > > + or watchdog reset. > > + For ETF, this reserved memory region is used for retention of trace > > + data synced from internal SRAM after a panic or watchdog reset. > > + > > + - description: Reserved meta data memory. Used for ETR and ETF sinks. > > + > > required: > > - compatible > > - reg > > @@ -115,6 +126,8 @@ examples: > > etr@20070000 { > > compatible = "arm,coresight-tmc", "arm,primecell"; > > reg = <0x20070000 0x1000>; > > + memory-region = <&etr_trace_mem_reserved>, > > + <&etr_mdata_mem_reserved>; > > > > clocks = <&oscclk6a>; > > clock-names = "apb_pclk";