Lines Matching refs:is
6 The Arm CoreSight SoC-400 is a comprehensive library of components for the creation of debug and
7 trace functionality within a system. The STM (System Trace Macrocell) is a trace source that
8 is integrated into a CoreSight system, designed primarily for high-bandwidth trace of
9 instrumentation embedded into software. This instrumentation is made up of memory-mapped writes to
12 register sets) which can be independently accessed thus there is no need for locking when various
24 TPIU (Trace Port Interface Unit) or saved in the RAM Circular Buffer which is called ETR (Embedded
25 Trace Router). TPIU is a 5 pin interface (4 data pins and clock) and external tool is required to
27 When ETR is used then one core in the system is responsible for processing that data, for example
33 ETR is a circular RAM buffer to which tracing data is saved. Since it may contain data from
34 various sources additional wrapping protocol is used to multiplex them. ``Coresight Trace
35 Formatter`` is used for that. Data is encoded into 16 bytes frames which holds up to 15 byte
36 of data. Circular RAM buffer size is limited to 4k thus there is a risk of data overflow. If
37 overflow occurs then data is lost but due to presence of synchronization opcodes in the STPv2
40 Data from ETR is handled on the device. It can be forwarded as-is to the host (e.g. using UART),
41 where a host tool is decoding the data or data can be decoded on-chip to output the data in human r…
44 buffer busyness is using own wrapper: Trace Buffer Monitor (TBM).
49 …is implemented. Custom frontend assumes that all required operations are executed in the context o…
50 whole message is written to that STMESP. Limited pool of sets is used leaving most of channels for
56 STMESP cannot be used before STM or ETR/TPIU is setup. In order to support early logging,
57 before infrastructure is ready a dedicated RAM buffer is used to which data is written. When
58 STM infrastructure readiness is notified (:c:func:`log_frontend_stmesp_etr_ready`) then RAM buffer
59 content is written to STMESP. Early logging is applicable only to the core which owns and configures
60 Coresight infrastructure (e.g. in case of NRF54H20 it is the Secure core).
65 …ogging is too slow (even though it is very fast). For cases like that a dedicated ``trace point`` …
68 * :c:func:`log_frontend_stmesp_tp` - It accepts single argument - index. Index is between
71 Index is between 0 and 65280. User data is 32 bit word.
73 It takes less than 100 ns to log a single trace point on NRF54H20 and it is approx. 7 times faster …
80 * Dictionary-based - assisted mode which is using dictionary-based logging. In this mode logging
82 is performed by the host tool. This mode takes less memory and is faster (2-3 times faster).
83 There is less data written so there is less chance of data overflow in ETR buffer.
84 * Standalone - data is decoded on chip and human-readable strings are printed. This mode requires
91 Each core (local domain) is using logging frontend which writes logging data to STMESP registers.
93 If TPIU is used as the output then there is no more software components needed. STPv2 stream
94 of data is composed by STM and send over TPIU.
96 If ETR RAM buffer is used then buffer owner core (``proxy``) is responsible for handling that data.
97 If dictionary-based logging is used then proxy just sends data as-is over UART.
98 If standalone logging is used then proxy is using :ref:`cs_trace_defmt` and
106 to STM, and is based on the :ref:`logging_guide_dictionary` feature of the logging API provided by
110 If the data goes to the ETR buffer, the proxy core's responsibility is to dump this data.
116 …e binary itself. Logging infrastructure is also very limited. On local domains it is just the fron…
117 …be sent to and processed by the application core, as the string formatting is offloaded to the hos…
118 * Logging is fast. It takes less than 1 us to log a simple message (up to 2 arguments) on NRF54H20.
120 Proxy core is using Nordic specific peripheral (TBM) to get ETR buffer busyness and send data over
121 UART. Nordic specific driver for ETR buffer is located in
128 Each core shall be build with that snippet. If any core wants to use it then application core is
149 The file will contain timestamps and the log messages in a format that is human-readable.
173 Frontend is writing to STMESP registers. Message format is aligned with the on chip decoder
176 ``Proxy`` is using Nordic specific peripheral (TBM) to get ETR buffer busyness and read and
177 decode data and send human-readable data over UART. Nordic specific driver for ETR buffer is
178 located in :zephyr_file:`drivers/misc/coresight/nrf_etr.c`. It is using :ref:`cs_trace_defmt` and
183 messages are longer and processing is time consuming. Compared to the dictionary-based mode logging
184 is 2-3 slower.
190 Each core shall be build with that snippet. If any core wants to use it then application core is
202 The following is an example log output::
240 …ns, such as the Radio core and Application core, ensure that each database is prefixed with the co…