On 25/10/2023 03:53, Tao Zhang wrote:
TPDM CMB subunits support two forms of CMB data set element creation: continuous and trace-on-change collection mode. Continuous change creates CMB data set elements on every CMBCLK edge. Trace-on-change creates CMB data set elements only when a new data set element differs in value from the previous element in a CMB data set. Set CMB_CR.MODE to 0 for continuous CMB collection mode. Set CMB_CR.MODE to 1 for trace-on-change CMB collection mode
Signed-off-by: Tao Zhang quic_taozha@quicinc.com Signed-off-by: Jinlong Mao quic_jinlmao@quicinc.com
.../ABI/testing/sysfs-bus-coresight-devices-tpdm | 10 +++ drivers/hwtracing/coresight/coresight-tpdm.c | 71 ++++++++++++++++++++++ drivers/hwtracing/coresight/coresight-tpdm.h | 12 ++++ 3 files changed, 93 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm index f07218e..ace7231 100644 --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm @@ -170,3 +170,13 @@ Contact: Jinlong Mao (QUIC) quic_jinlmao@quicinc.com, Tao Zhang (QUIC) <quic_t Description: (RW) Set/Get the MSR(mux select register) for the DSB subunit TPDM.
+What: /sys/bus/coresight/devices/<tpdm-name>/cmb_mode +Date: March 2023 +KernelVersion 6.7 +Contact: Jinlong Mao (QUIC) quic_jinlmao@quicinc.com, Tao Zhang (QUIC) quic_taozha@quicinc.com +Description: (Write) Set the data collection mode of CMB tpdm.
I know it's expanded elsewhere, but it's probably worth expanding the CMB abbreviation here as well so people reading the docs don't have to go into the code.
Otherwise:
Reviewed-by: James Clark james.clark@arm.com
Accepts only one of the 2 values - 0 or 1.
0 : Continuous CMB collection mode.
1 : Trace-on-change CMB collection mode.
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c index c8bb388..efb376e 100644 --- a/drivers/hwtracing/coresight/coresight-tpdm.c +++ b/drivers/hwtracing/coresight/coresight-tpdm.c @@ -148,6 +148,18 @@ static umode_t tpdm_dsb_is_visible(struct kobject *kobj, return 0; }
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