[PATCH v7 00/10] Add support to configure TPDM CMB subunit
Tao Zhang
quic_taozha at quicinc.com
Sat Feb 3 21:30:31 PST 2024
Introduction of TPDM CMB(Continuous Multi Bit) subunit
CMB 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 CMB makes trace elements in two modes. In ‘continuous’ mode, every
valid data cycle creates an element. In ‘trace on change’ mode, when
valid data changes on the bus, a trace element is created. In
continuous mode, all cycles where this condition is true create trace
elements. In trace on change mode, a data element is only when the
previously sampled input is different from the current sampled input.
The CMB subunit must be configured prior to enablement. This series
adds support for TPDM to configure the configure CMB 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 CMB subunit.
e.g.
root at qemuarm64:/sys/devices/platform/soc at 0/684c000.tpdm/tpdm0# ls -l
-rw-r--r-- 1 root root 4096 Jan 1 00:00 cmb_mode
drwxr-xr-x 2 root root 0 Jan 1 00:00 cmb_msr
drwxr-xr-x 2 root root 0 Jan 1 00:00 cmb_patt
drwxr-xr-x 2 root root 0 Jan 1 00:00 cmb_trig_patt
-rw-r--r-- 1 root root 4096 Jan 1 00:00 cmb_trig_ts
-rw-r--r-- 1 root root 4096 Jan 1 00:00 cmb_ts_all
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
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
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 enable_source
--w------- 1 root root 4096 Jan 1 00:00 integration_test
drwxr-xr-x 2 root root 0 Ja? 1 00:00 power
--w------- 1 root root 4096 Jan 1 00:00 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 CMB subunit. Enable coresight sink first.
echo 1 > /sys/bus/coresight/devices/tmc_etf0/enable_sink
echo 1 > /sys/bus/coresight/devices/tpdm0/reset_dataset
echo 1 > /sys/bus/coresight/devices/tpdm0/cmb_mode
echo 1 > /sys/bus/coresight/devices/tpdm0/cmb_patt/enable_ts
echo 0xFFFFFFFF > /sys/bus/coresight/devices/tpdm0/cmb_patt/tpmr0
echo 0 > /sys/bus/coresight/devices/tpdm0/cmb_trig_ts
echo 0xFFFFFFFF > /sys/bus/coresight/devices/tpdm0/cmb_trig_patt/xpr1
echo 1 > /sys/bus/coresight/devices/tpdm0/enable_source
codelinaro link:
https://git.codelinaro.org/clo/linux-kernel/coresight/-/commits/tpdm-cmb-v7
Changes in V7:
1. Rename "tpdm_clear_element_size" to "tpda_clear_element_size" in
the patch#5.
-- Suzuki K Poulose
2. Remove the stale comments in "tpda_enable_port".
-- Suzuki K Poulose
Changes in V6:
1. Clear all the relevant fields before setting them in the function
"tpda_set_element_size". In patch#5.
-- Suzuki K Poulose
2. Leave a space after/before '/*' & '*/'. In patch#7 #8.
-- Suzuki K Poulose
Changes in V5:
1. Return directly to refine the process of "tpdm_enable_dsb" and
"tpdm_disable_dsb" if the TPDM does not support DSB dataset.
-- Suzuki K Poulose
2. Change the new property name from "qcom,cmb-element-size" to
"qcom,cmb-element-bits". And update the property name to the new
tpdm example which supports the CMB dataset.
-- Krzysztof
3. Drop unnecessary () around the drvdata member access in patch#5.
-- Suzuki K Poulose
4. Replace the error code "-EEXIST" with the port number in detecting
multiple TPDMs on one input port. In patch#5.
-- Suzuki K Poulose
5. Due to the modification of the new property name, the searched
property name was changed from "qcom,cmb-element-size" to
"qcom,cmb-element-bits". In patch#5.
6. Replace the judgement "tpdm_has_cmb_dataset(drvdata)" with
"drvdata->cmb" in the function "tpdm_reset_datasets". In patch#6.
-- Suzuki K Poulose
7. Drop unnecessary () around kstrtoul() in the function
"cmb_mode_store". In patch#6.
-- Suzuki K Poulose
8. Update the date and the kernel version in the Document.
-- Suzuki K Poulose
9. Initialize the return value to "-EINVAL" and remove the unnecessary
code in the function "enable_ts_show". In patch#8.
-- Suzuki K Poulose
10. Replace spin lock/unlock with guard(spinlock). In patch#8.
-- Suzuki K Poulose
11. Drop _rw from the macro "tpdm_patt_enable_ts_rw". In patch#8.
-- Suzuki K Poulose
Changes in V4:
1. Replace spin lock/unlock to avoid forgetting to unlock when the
function exits.
-- Suzuki K Poulose
2. Move the helper "tpdm_has_dsb_dataset" to the header file.
-- Suzuki K Poulose
3. Fix the incorrect property of the sample in the documents.
-- James Clark
4. Clear the dsb/cmb element size directly in the clear helper.
-- Suzuki K Poulose
5. Correct the comment of "tpdm_read_element_size".
-- Suzuki K Poulose
6. Call the helper "tpdm_has_dsb/cmb_dataset" in TPDA driver to
check what dataset the TPDM supports.
-- Suzuki K Poulose
7. Refine the dsb/cmb dataset support check in enable/disable functions.
-- Suzuki K Poulose
8. Get rid of redundant code in function "set_cmb_tier".
-- Suzuki K Poulose
9. Since one SysFs file should follow "one value", use "dev_ext_attribute"
to instead of the previous "enable_ts" Sysfs file approach.
-- Suzuki K Poulose
10. Change the kernel version to 6.9 for the MSR related SysFs file.
-- James Clark
11. Refine the function "tpdm_simple_dataset_store".
-- Suzuki K Poulose
Changes in V3:
1. Add 8-bit support to the description in the TPDM devicetree document.
-- Rob Herring
2. Change how the result is produced in "tpdm_read_element_size".
-- James Clark
3. Calling "tpdm_clear_element_size" at the beginning of
"tpda_enable_port".
-- James Clark
4. Use "dsb_esize" and "cmb_esize" to determine whether multiple TPDMs
are detected on a TPDA input port in "tpda_get_element_size".
-- James Clark
5. Modify the judgment logic in "tpda_enable_port".
-- James Clark
6. Add more description of "cmb_mode" to TPDM SysFS document.
-- James Clark
Changes in V2:
1. Optimizate and modify this patch series based on the patch series
"Add support to configure TPDM CMB subunit".
2. Modify the functions that read the element size of DSB/CMB in TPDA driver.
Tao Zhang (10):
coresight-tpdm: Optimize the store function of tpdm simple dataset
coresight-tpdm: Optimize the useage of tpdm_has_dsb_dataset
dt-bindings: arm: qcom,coresight-tpdm: Add support for CMB element
size
coresight-tpdm: Add CMB dataset support
coresight-tpda: Add support to configure CMB element
coresight-tpdm: Add support to configure CMB
coresight-tpdm: Add pattern registers support for CMB
coresight-tpdm: Add timestamp control register support for the CMB
dt-bindings: arm: qcom,coresight-tpdm: Add support for TPDM CMB MSR
register
coresight-tpdm: Add msr register support for CMB
.../testing/sysfs-bus-coresight-devices-tpdm | 87 ++++
.../bindings/arm/qcom,coresight-tpdm.yaml | 35 ++
drivers/hwtracing/coresight/coresight-tpda.c | 130 ++---
drivers/hwtracing/coresight/coresight-tpda.h | 6 +
drivers/hwtracing/coresight/coresight-tpdm.c | 455 ++++++++++++++++--
drivers/hwtracing/coresight/coresight-tpdm.h | 113 +++++
6 files changed, 729 insertions(+), 97 deletions(-)
--
2.17.1
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