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

Suzuki K Poulose suzuki.poulose at arm.com
Wed Sep 27 01:58:11 PDT 2023


On 27/09/2023 07:37, Tao Zhang wrote:
> 
> 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 

Sure, that is fine. The proposed changes to the other patch look good
too.

Suzuki



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