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-rw-r--r--Documentation/acpi/debug.txt148
-rw-r--r--Documentation/kernel-parameters.txt75
2 files changed, 171 insertions, 52 deletions
diff --git a/Documentation/acpi/debug.txt b/Documentation/acpi/debug.txt
new file mode 100644
index 000000000000..65bf47c46b6d
--- /dev/null
+++ b/Documentation/acpi/debug.txt
@@ -0,0 +1,148 @@
1 ACPI Debug Output
2
3
4The ACPI CA, the Linux ACPI core, and some ACPI drivers can generate debug
5output. This document describes how to use this facility.
6
7Compile-time configuration
8--------------------------
9
10ACPI debug output is globally enabled by CONFIG_ACPI_DEBUG. If this config
11option is turned off, the debug messages are not even built into the
12kernel.
13
14Boot- and run-time configuration
15--------------------------------
16
17When CONFIG_ACPI_DEBUG=y, you can select the component and level of messages
18you're interested in. At boot-time, use the acpi.debug_layer and
19acpi.debug_level kernel command line options. After boot, you can use the
20debug_layer and debug_level files in /sys/module/acpi/parameters/ to control
21the debug messages.
22
23debug_layer (component)
24-----------------------
25
26The "debug_layer" is a mask that selects components of interest, e.g., a
27specific driver or part of the ACPI interpreter. To build the debug_layer
28bitmask, look for the "#define _COMPONENT" in an ACPI source file.
29
30You can set the debug_layer mask at boot-time using the acpi.debug_layer
31command line argument, and you can change it after boot by writing values
32to /sys/module/acpi/parameters/debug_layer.
33
34The possible components are defined in include/acpi/acoutput.h and
35include/acpi/acpi_drivers.h. Reading /sys/module/acpi/parameters/debug_layer
36shows the supported mask values, currently these:
37
38 ACPI_UTILITIES 0x00000001
39 ACPI_HARDWARE 0x00000002
40 ACPI_EVENTS 0x00000004
41 ACPI_TABLES 0x00000008
42 ACPI_NAMESPACE 0x00000010
43 ACPI_PARSER 0x00000020
44 ACPI_DISPATCHER 0x00000040
45 ACPI_EXECUTER 0x00000080
46 ACPI_RESOURCES 0x00000100
47 ACPI_CA_DEBUGGER 0x00000200
48 ACPI_OS_SERVICES 0x00000400
49 ACPI_CA_DISASSEMBLER 0x00000800
50 ACPI_COMPILER 0x00001000
51 ACPI_TOOLS 0x00002000
52 ACPI_BUS_COMPONENT 0x00010000
53 ACPI_AC_COMPONENT 0x00020000
54 ACPI_BATTERY_COMPONENT 0x00040000
55 ACPI_BUTTON_COMPONENT 0x00080000
56 ACPI_SBS_COMPONENT 0x00100000
57 ACPI_FAN_COMPONENT 0x00200000
58 ACPI_PCI_COMPONENT 0x00400000
59 ACPI_POWER_COMPONENT 0x00800000
60 ACPI_CONTAINER_COMPONENT 0x01000000
61 ACPI_SYSTEM_COMPONENT 0x02000000
62 ACPI_THERMAL_COMPONENT 0x04000000
63 ACPI_MEMORY_DEVICE_COMPONENT 0x08000000
64 ACPI_VIDEO_COMPONENT 0x10000000
65 ACPI_PROCESSOR_COMPONENT 0x20000000
66
67debug_level
68-----------
69
70The "debug_level" is a mask that selects different types of messages, e.g.,
71those related to initialization, method execution, informational messages, etc.
72To build debug_level, look at the level specified in an ACPI_DEBUG_PRINT()
73statement.
74
75The ACPI interpreter uses several different levels, but the Linux
76ACPI core and ACPI drivers generally only use ACPI_LV_INFO.
77
78You can set the debug_level mask at boot-time using the acpi.debug_level
79command line argument, and you can change it after boot by writing values
80to /sys/module/acpi/parameters/debug_level.
81
82The possible levels are defined in include/acpi/acoutput.h. Reading
83/sys/module/acpi/parameters/debug_level shows the supported mask values,
84currently these:
85
86 ACPI_LV_INIT 0x00000001
87 ACPI_LV_DEBUG_OBJECT 0x00000002
88 ACPI_LV_INFO 0x00000004
89 ACPI_LV_INIT_NAMES 0x00000020
90 ACPI_LV_PARSE 0x00000040
91 ACPI_LV_LOAD 0x00000080
92 ACPI_LV_DISPATCH 0x00000100
93 ACPI_LV_EXEC 0x00000200
94 ACPI_LV_NAMES 0x00000400
95 ACPI_LV_OPREGION 0x00000800
96 ACPI_LV_BFIELD 0x00001000
97 ACPI_LV_TABLES 0x00002000
98 ACPI_LV_VALUES 0x00004000
99 ACPI_LV_OBJECTS 0x00008000
100 ACPI_LV_RESOURCES 0x00010000
101 ACPI_LV_USER_REQUESTS 0x00020000
102 ACPI_LV_PACKAGE 0x00040000
103 ACPI_LV_ALLOCATIONS 0x00100000
104 ACPI_LV_FUNCTIONS 0x00200000
105 ACPI_LV_OPTIMIZATIONS 0x00400000
106 ACPI_LV_MUTEX 0x01000000
107 ACPI_LV_THREADS 0x02000000
108 ACPI_LV_IO 0x04000000
109 ACPI_LV_INTERRUPTS 0x08000000
110 ACPI_LV_AML_DISASSEMBLE 0x10000000
111 ACPI_LV_VERBOSE_INFO 0x20000000
112 ACPI_LV_FULL_TABLES 0x40000000
113 ACPI_LV_EVENTS 0x80000000
114
115Examples
116--------
117
118For example, drivers/acpi/bus.c contains this:
119
120 #define _COMPONENT ACPI_BUS_COMPONENT
121 ...
122 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device insertion detected\n"));
123
124To turn on this message, set the ACPI_BUS_COMPONENT bit in acpi.debug_layer
125and the ACPI_LV_INFO bit in acpi.debug_level. (The ACPI_DEBUG_PRINT
126statement uses ACPI_DB_INFO, which is macro based on the ACPI_LV_INFO
127definition.)
128
129Enable all AML "Debug" output (stores to the Debug object while interpreting
130AML) during boot:
131
132 acpi.debug_layer=0xffffffff acpi.debug_level=0x2
133
134Enable PCI and PCI interrupt routing debug messages:
135
136 acpi.debug_layer=0x400000 acpi.debug_level=0x4
137
138Enable all ACPI hardware-related messages:
139
140 acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
141
142Enable all ACPI_DB_INFO messages after boot:
143
144 # echo 0x4 > /sys/module/acpi/parameters/debug_level
145
146Show all valid component values:
147
148 # cat /sys/module/acpi/parameters/debug_layer
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 343e0f0f84b6..e8951118deaf 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -198,59 +198,30 @@ and is between 256 and 4096 characters. It is defined in the file
198 that require a timer override, but don't have 198 that require a timer override, but don't have
199 HPET 199 HPET
200 200
201 acpi.debug_layer= [HW,ACPI] 201 acpi.debug_layer= [HW,ACPI,ACPI_DEBUG]
202 acpi.debug_level= [HW,ACPI,ACPI_DEBUG]
202 Format: <int> 203 Format: <int>
203 Each bit of the <int> indicates an ACPI debug layer, 204 CONFIG_ACPI_DEBUG must be enabled to produce any ACPI
204 1: enable, 0: disable. It is useful for boot time 205 debug output. Bits in debug_layer correspond to a
205 debugging. After system has booted up, it can be set 206 _COMPONENT in an ACPI source file, e.g.,
206 via /sys/module/acpi/parameters/debug_layer. 207 #define _COMPONENT ACPI_PCI_COMPONENT
207 CONFIG_ACPI_DEBUG must be enabled for this to produce any output. 208 Bits in debug_level correspond to a level in
208 Available bits (add the numbers together) to enable debug output 209 ACPI_DEBUG_PRINT statements, e.g.,
209 for specific parts of the ACPI subsystem: 210 ACPI_DEBUG_PRINT((ACPI_DB_INFO, ...
210 0x01 utilities 0x02 hardware 0x04 events 0x08 tables 211 See Documentation/acpi/debug.txt for more information
211 0x10 namespace 0x20 parser 0x40 dispatcher 212 about debug layers and levels.
212 0x80 executer 0x100 resources 0x200 acpica debugger 213
213 0x400 os services 0x800 acpica disassembler. 214 Enable AML "Debug" output, i.e., stores to the Debug
214 The number can be in decimal or prefixed with 0x in hex. 215 object while interpreting AML:
215 Warning: Many of these options can produce a lot of 216 acpi.debug_layer=0xffffffff acpi.debug_level=0x2
216 output and make your system unusable. Be very careful. 217 Enable PCI/PCI interrupt routing info messages:
217 218 acpi.debug_layer=0x400000 acpi.debug_level=0x4
218 acpi.debug_level= [HW,ACPI] 219 Enable all messages related to ACPI hardware:
219 Format: <int> 220 acpi.debug_layer=0x2 acpi.debug_level=0xffffffff
220 Each bit of the <int> indicates an ACPI debug level, 221
221 which corresponds to the level in an ACPI_DEBUG_PRINT 222 Some values produce so much output that the system is
222 statement. After system has booted up, this mask 223 unusable. The "log_buf_len" parameter may be useful
223 can be set via /sys/module/acpi/parameters/debug_level. 224 if you need to capture more output.
224
225 CONFIG_ACPI_DEBUG must be enabled for this to produce
226 any output. The number can be in decimal or prefixed
227 with 0x in hex. Some of these options produce so much
228 output that the system is unusable.
229
230 The following global components are defined by the
231 ACPI CA:
232 0x01 error
233 0x02 warn
234 0x04 init
235 0x08 debug object
236 0x10 info
237 0x20 init names
238 0x40 parse
239 0x80 load
240 0x100 dispatch
241 0x200 execute
242 0x400 names
243 0x800 operation region
244 0x1000 bfield
245 0x2000 tables
246 0x4000 values
247 0x8000 objects
248 0x10000 resources
249 0x20000 user requests
250 0x40000 package
251 The number can be in decimal or prefixed with 0x in hex.
252 Warning: Many of these options can produce a lot of
253 output and make your system unusable. Be very careful.
254 225
255 acpi.power_nocheck= [HW,ACPI] 226 acpi.power_nocheck= [HW,ACPI]
256 Format: 1/0 enable/disable the check of power state. 227 Format: 1/0 enable/disable the check of power state.