Commit 99ed6bfa authored by Changbin Du's avatar Changbin Du Committed by Rafael J. Wysocki
Browse files

Documentation: ACPI: move debug.txt to firmware-guide/acpi and convert to reST 



This converts the plain text documentation to reStructuredText format
and adds it to Sphinx TOC tree.

No essential content change.

Signed-off-by: default avatarChangbin Du <changbin.du@gmail.com>
Reviewed-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 05000042

Documentation/acpi/debug.txt→Documentation/firmware-guide/acpi/debug.rst

+17 −14
Original line number Diff line number Diff line 
			ACPI Debug Output

.. SPDX-License-Identifier: GPL-2.0



=================

ACPI Debug Output

=================



The ACPI CA, the Linux ACPI core, and some ACPI drivers can generate debug

output.  This document describes how to use this facility.



Compile-time configuration

--------------------------

==========================



ACPI debug output is globally enabled by CONFIG_ACPI_DEBUG.  If this config

option is turned off, the debug messages are not even built into the

kernel.



Boot- and run-time configuration

--------------------------------

================================



When CONFIG_ACPI_DEBUG=y, you can select the component and level of messages

you're interested in.  At boot-time, use the acpi.debug_layer and
@@ -21,7 +24,7 @@ debug_layer and debug_level files in /sys/module/acpi/parameters/ to control 
the debug messages.



debug_layer (component)

-----------------------

=======================



The "debug_layer" is a mask that selects components of interest, e.g., a

specific driver or part of the ACPI interpreter.  To build the debug_layer
@@ -33,7 +36,7 @@ to /sys/module/acpi/parameters/debug_layer. 


The possible components are defined in include/acpi/acoutput.h and

include/acpi/acpi_drivers.h.  Reading /sys/module/acpi/parameters/debug_layer

shows the supported mask values, currently these:

shows the supported mask values, currently these::



    ACPI_UTILITIES                  0x00000001

    ACPI_HARDWARE                   0x00000002
@@ -65,7 +68,7 @@ shows the supported mask values, currently these: 
    ACPI_PROCESSOR_COMPONENT        0x20000000



debug_level

-----------

===========



The "debug_level" is a mask that selects different types of messages, e.g.,

those related to initialization, method execution, informational messages, etc.
@@ -81,7 +84,7 @@ to /sys/module/acpi/parameters/debug_level. 


The possible levels are defined in include/acpi/acoutput.h.  Reading

/sys/module/acpi/parameters/debug_level shows the supported mask values,

currently these:

currently these::



    ACPI_LV_INIT                    0x00000001

    ACPI_LV_DEBUG_OBJECT            0x00000002
@@ -113,9 +116,9 @@ currently these: 
    ACPI_LV_EVENTS                  0x80000000



Examples

--------

========



For example, drivers/acpi/bus.c contains this:

For example, drivers/acpi/bus.c contains this::



    #define _COMPONENT              ACPI_BUS_COMPONENT

    ...
@@ -127,22 +130,22 @@ statement uses ACPI_DB_INFO, which is macro based on the ACPI_LV_INFO 
definition.)



Enable all AML "Debug" output (stores to the Debug object while interpreting

AML) during boot:

AML) during boot::



    acpi.debug_layer=0xffffffff acpi.debug_level=0x2



Enable PCI and PCI interrupt routing debug messages:

Enable PCI and PCI interrupt routing debug messages::



    acpi.debug_layer=0x400000 acpi.debug_level=0x4



Enable all ACPI hardware-related messages:

Enable all ACPI hardware-related messages::



    acpi.debug_layer=0x2 acpi.debug_level=0xffffffff



Enable all ACPI_DB_INFO messages after boot:

Enable all ACPI_DB_INFO messages after boot::



    # echo 0x4 > /sys/module/acpi/parameters/debug_level



Show all valid component values:

Show all valid component values::



    # cat /sys/module/acpi/parameters/debug_layer

Documentation/firmware-guide/acpi/index.rst

+2 −1
Original line number Diff line number Diff line
@@ -14,6 +14,7 @@ ACPI Support 
   osi

   method-customizing

   DSD-properties-rules

   debug

   gpio-properties

   i2c-muxes

   acpi-lid

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