ACPI: Improve acpi debug documentation

Now we use acpi.debug_level and acpi.debug_layer as kernel boot
parameters instead of acpi_dbg_level and acpi_dbg_layer.
Thanks to Andi Kleen for pointing it out.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 27 insertions, 5 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 12533a958c51..e3394eb42cb7 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -181,19 +181,41 @@ and is between 256 and 4096 characters. It is defined in the file
                         that require a timer override, but don't have
                         HPET
 
-        acpi_dbg_layer= [HW,ACPI]
+        acpi.debug_layer=       [HW,ACPI]
                         Format: <int>
                         Each bit of the <int> indicates an ACPI debug layer,
                         1: enable, 0: disable. It is useful for boot time
                         debugging. After system has booted up, it can be set
-                        via /proc/acpi/debug_layer.
-
-        acpi_dbg_level= [HW,ACPI]
+                        via /sys/module/acpi/parameters/debug_layer.
+                        CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
+                        Available bits (add the numbers together) to enable debug output
+                        for specific parts of the ACPI subsystem:
+                        0x01 utilities 0x02 hardware 0x04 events 0x08 tables
+                        0x10 namespace 0x20 parser 0x40 dispatcher
+                        0x80 executer 0x100 resources 0x200 acpica debugger
+                        0x400 os services 0x800 acpica disassembler.
+                        The number can be in decimal or prefixed with 0x in hex.
+                        Warning: Many of these options can produce a lot of
+                        output and make your system unusable. Be very careful.
+
+        acpi.debug_level=       [HW,ACPI]
                         Format: <int>
                         Each bit of the <int> indicates an ACPI debug level,
                         1: enable, 0: disable. It is useful for boot time
                         debugging. After system has booted up, it can be set
-                        via /proc/acpi/debug_level.
+                        via /sys/module/acpi/parameters/debug_level.
+                        CONFIG_ACPI_DEBUG must be enabled for this to produce any output.
+                        Available bits (add the numbers together) to enable different
+                        debug output levels of the ACPI subsystem:
+                        0x01 error 0x02 warn 0x04 init 0x08 debug object
+                        0x10 info 0x20 init names 0x40 parse 0x80 load
+                        0x100 dispatch 0x200 execute 0x400 names 0x800 operation region
+                        0x1000 bfield 0x2000 tables 0x4000 values 0x8000 objects
+                        0x10000 resources 0x20000 user requests 0x40000 package.
+                        The number can be in decimal or prefixed with 0x in hex.
+                        Warning: Many of these options can produce a lot of
+                        output and make your system unusable. Be very careful.
+
 
         acpi_fake_ecdt  [HW,ACPI] Workaround failure due to BIOS lacking ECDT