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-rw-r--r--Documentation/acpi/dsdt-override.txt15
-rwxr-xr-xDocumentation/acpi/initramfs-add-dsdt.sh43
-rw-r--r--Documentation/acpi/method-tracing.txt26
3 files changed, 84 insertions, 0 deletions
diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt
new file mode 100644
index 000000000000..5008f256a2db
--- /dev/null
+++ b/Documentation/acpi/dsdt-override.txt
@@ -0,0 +1,15 @@
+Linux supports two methods of overriding the BIOS DSDT:
+
+CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel.
+
+CONFIG_ACPI_CUSTOM_DSDT_INITRD adds the image to the initrd.
+
+When to use these methods is described in detail on the
+Linux/ACPI home page:
+http://www.lesswatts.org/projects/acpi/overridingDSDT.php
+
+Note that if both options are used, the DSDT supplied
+by the INITRD method takes precedence.
+
+Documentation/initramfs-add-dsdt.sh is provided for convenience
+for use with the CONFIG_ACPI_CUSTOM_DSDT_INITRD method.
diff --git a/Documentation/acpi/initramfs-add-dsdt.sh b/Documentation/acpi/initramfs-add-dsdt.sh
new file mode 100755
index 000000000000..17ef6e838e14
--- /dev/null
+++ b/Documentation/acpi/initramfs-add-dsdt.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+# Adds a DSDT file to the initrd (if it's an initramfs)
+# first argument is the name of archive
+# second argument is the name of the file to add
+# The file will be copied as /DSDT.aml
+
+# 20060126: fix "Premature end of file" with some old cpio (Roland Robic)
+# 20060205: this time it should really work
+
+# check the arguments
+if [ $# -ne 2 ]; then
+ program_name=$(basename $0)
+ echo "\
+$program_name: too few arguments
+Usage: $program_name initrd-name.img DSDT-to-add.aml
+Adds a DSDT file to an initrd (in initramfs format)
+
+ initrd-name.img: filename of the initrd in initramfs format
+ DSDT-to-add.aml: filename of the DSDT file to add
+ " 1>&2
+ exit 1
+fi
+
+# we should check it's an initramfs
+
+tempcpio=$(mktemp -d)
+# cleanup on exit, hangup, interrupt, quit, termination
+trap 'rm -rf $tempcpio' 0 1 2 3 15
+
+# extract the archive
+gunzip -c "$1" > "$tempcpio"/initramfs.cpio || exit 1
+
+# copy the DSDT file at the root of the directory so that we can call it "/DSDT.aml"
+cp -f "$2" "$tempcpio"/DSDT.aml
+
+# add the file
+cd "$tempcpio"
+(echo DSDT.aml | cpio --quiet -H newc -o -A -O "$tempcpio"/initramfs.cpio) || exit 1
+cd "$OLDPWD"
+
+# re-compress the archive
+gzip -c "$tempcpio"/initramfs.cpio > "$1"
+
diff --git a/Documentation/acpi/method-tracing.txt b/Documentation/acpi/method-tracing.txt
new file mode 100644
index 000000000000..f6efb1ea559a
--- /dev/null
+++ b/Documentation/acpi/method-tracing.txt
@@ -0,0 +1,26 @@
+/sys/module/acpi/parameters/:
+
+trace_method_name
+ The AML method name that the user wants to trace
+
+trace_debug_layer
+ The temporary debug_layer used when tracing the method.
+ Using 0xffffffff by default if it is 0.
+
+trace_debug_level
+ The temporary debug_level used when tracing the method.
+ Using 0x00ffffff by default if it is 0.
+
+trace_state
+ The status of the tracing feature.
+
+ "enabled" means this feature is enabled
+ and the AML method is traced every time it's executed.
+
+ "1" means this feature is enabled and the AML method
+ will only be traced during the next execution.
+
+ "disabled" means this feature is disabled.
+ Users can enable/disable this debug tracing feature by
+ "echo string > /sys/module/acpi/parameters/trace_state".
+ "string" should be one of "enable", "disable" and "1".
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