[PATCH v9 00/13] Add support to configure TPDM DSB subunit

Tao Zhang quic_taozha at quicinc.com
Tue Sep 26 23:37:57 PDT 2023


On 9/26/2023 9:12 PM, Suzuki K Poulose wrote:
> On 14/09/2023 06:43, Tao Zhang wrote:
>> Introduction of TPDM DSB subunit
>> DSB subunit is responsible for creating a dataset element, and is also
>> optionally responsible for packing it to fit multiple elements on a
>> single ATB transfer if possible in the configuration. The TPDM Core
>> Datapath requests timestamps be stored by the TPDA and then delivering
>> ATB sized data (depending on ATB width and element size, this could
>> be smaller or larger than a dataset element) to the ATB Mast FSM.
>>
>> The DSB subunit must be configured prior to enablement. This series
>> adds support for TPDM to configure the configure DSB subunit.
>>
>> Once this series patches are applied properly, the new tpdm nodes for
>> should be observed at the tpdm path /sys/bus/coresight/devices/tpdm*
>> which supports DSB subunit.
>> e.g.
>> root at qemuarm64:/sys/devices/platform/soc at 0/6c08000.tpdm/tpdm1# ls -l
>> drwxr-xr-x    2 root     root             0 Jan  1 00:00 connections
>> drwxr-xr-x    2 root     root             0 Jan  1 00:00 dsb_edge
>> -rw-r--r--    1 root     root          4096 Jan  1 00:00 dsb_mode
>> drwxr-xr-x    2 root     root             0 Jan  1 00:00 dsb_msr
>> drwxr-xr-x    2 root     root             0 Jan  1 00:00 dsb_patt
>> -rw-r--r--    1 root     root          4096 Jan  1 00:00 dsb_patt_ts
>> -rw-r--r--    1 root     root          4096 Jan  1 00:00 dsb_patt_type
>> drwxr-xr-x    2 root     root             0 Jan  1 00:00 dsb_trig_patt
>> -rw-r--r--    1 root     root          4096 Jan  1 00:00 dsb_trig_ts
>> -rw-r--r--    1 root     root          4096 Jan  1 00:00 dsb_trig_type
>> -rw-r--r--    1 root     root          4096 Jan  1 00:02 enable_source
>> --w-------    1 root     root          4096 Jan  1 00:00 
>> integration_test
>> drwxr-xr-x    2 root     root             0 Jan  1 00:00 power
>> --w-------    1 root     root          4096 Jan  1 00:02 reset_dataset
>> lrwxrwxrwx    1 root     root             0 Apr  5  2021 subsystem -> 
>> ../../../../../bus/coresight
>> -rw-r--r--    1 root     root          4096 Apr  5  2021 uevent
>> -r--r--r--    1 root     root          4096 Jan  1 00:00 
>> waiting_for_supplier
>>
>> We can use the commands are similar to the below to configure the
>> TPDMs which support DSB subunit. Enable coresight sink first.
>> echo 1 > /sys/bus/coresight/devices/tmc_etf0/enable_sink
>> echo 1 > /sys/bus/coresight/devices/tpdm1/reset_dataset
>> echo 0x3 > /sys/bus/coresight/devices/tpdm1/dsb_edge/ctrl_idx
>> echo 0x1 > /sys/bus/coresight/devices/tpdm1/dsb_edge/ctrl_mask
>> echo 0x0 > /sys/bus/coresight/devices/tpdm1/dsb_edge/ctrl_val
>> echo 1 > /sys/bus/coresight/devices/tpdm1/dsb_patt/enable_ts
>> echo 1 > /sys/bus/coresight/devices/tpdm1/dsb_patt/set_type
>> echo 0 > /sys/bus/coresight/devices/tpdm1/dsb_trig_ts
>> echo 0xFFFFFFFF > /sys/bus/coresight/devices/tpdm1/dsb_patt/tpmr5
>> echo 0xFFFFFFFF > /sys/bus/coresight/devices/tpdm1/dsb_trig_patt/xpr2
>> echo 1 > /sys/bus/coresight/devices/tpdm1/enable_source
>>
>
> I have reviewed this set, except for the last patch, rest looks fine.
> If you could resend the series with the comments addressed, we could
> queue this.

That's great. Thanks for your review.

I also want to make a minor change.

Can I rename "tpdm_dsb_attrs_grp" to "tpdm_dsb_attr_grp" in the next 
patch series?


Best,

Tao

>
> Suzuki



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