Documentation/ABI/testing/debugfs-driver-dcc

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/debugfs-driver-dcc

File Facts

System
Linux kernel
Corpus path
Documentation/ABI/testing/debugfs-driver-dcc
Extension
[no extension]
Size
3604 bytes
Lines
128
Domain
Support Tooling And Documentation
Bucket
Documentation
Inferred role
Support Tooling And Documentation: Documentation
Status
atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

What:           /sys/kernel/debug/dcc/.../ready
Date:           December 2022
Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
Description:
		This file is used to check the status of the dcc
		hardware if it's ready to receive user configurations.
		A 'Y' here indicates dcc is ready.

What:           /sys/kernel/debug/dcc/.../trigger
Date:           December 2022
Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
Description:
		This is the debugfs interface for manual software
		triggers. The trigger can be invoked by writing '1'
		to the file.

What:           /sys/kernel/debug/dcc/.../config_reset
Date:           December 2022
Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
Description:
		This file is used to reset the configuration of
		a dcc driver to the default configuration. When '1'
		is written to the file, all the previous addresses
		stored in the driver gets removed and users need to
		reconfigure addresses again.

What:           /sys/kernel/debug/dcc/.../[list-number]/config
Date:		 December 2022
Contact:        Souradeep Chowdhury <quic_schowdhu@quicinc.com>
Description:
		This stores the addresses of the registers which
		can be read in case of a hardware crash or manual
		software triggers. The input addresses type
		can be one of following dcc instructions: read,
		write, read-write, and loop type. The lists need to
		be configured sequentially and not in a overlapping
		manner; e.g. users can jump to list x only after
		list y is configured and enabled. The input format for
		each type is as follows:

	        i) Read instruction

		   ::

		     echo R <addr> <n> <bus> >/sys/kernel/debug/dcc/../[list-number]/config

		   where:

		   <addr>
			The address to be read.

		   <n>
			The addresses word count, starting from address <1>.
			Each word is 32 bits (4 bytes). If omitted, defaulted
			to 1.

		   <bus type>
			The bus type, which can be either 'apb' or 'ahb'.
			The default is 'ahb' if leaved out.

		ii) Write instruction

		    ::

		      echo W <addr> <n> <bus type> > /sys/kernel/debug/dcc/../[list-number]/config

		    where:

		    <addr>
			The address to be written.

Annotation

Implementation Notes