What: /sys/kernel/debug/dcc/.../ready
Date: December 2022
Contact: Souradeep Chowdhury <[email protected]>
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 <[email protected]>
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 <[email protected]>
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 <[email protected]>
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.
<n>
The value to be written at <addr>.
<bus type>
The bus type, which can be either 'apb' or 'ahb'.
iii) Read-write instruction
::
echo RW <addr> <n> <mask> > /sys/kernel/debug/dcc/../[list-number]/config
where:
<addr>
The address to be read and written.
<n>
The value to be written at <addr>.
<mask>
The value mask.
iv) Loop instruction
::
echo L <loop count> <address count> <address>... > /sys/kernel/debug/dcc/../[list-number]/config
where:
<loop count>
Number of iterations
<address count>
total number of addresses to be written
<address>
Space-separated list of addresses.
What: /sys/kernel/debug/dcc/.../[list-number]/enable
Date: December 2022
Contact: Souradeep Chowdhury <[email protected]>
Description:
This debugfs interface is used for enabling the
the dcc hardware. A file named "enable" is in the
directory list number where users can enable/disable
the specific list by writing boolean (1 or 0) to the
file.
On enabling the dcc, all the addresses specified
by the user for the corresponding list is written
into dcc sram which is read by the dcc hardware
on manual or crash induced triggers. Lists must
be configured and enabled sequentially, e.g. list
2 can only be enabled when list 1 have so.
Codebase Browser
linux