add undervolt

git-svn-id: https://svn.disconnected-by-peer.at/svn/linamh/trunk/linamh@1543 6952d904-891a-0410-993b-d76249ca496b

sys-power/undervolt/files/undervolt.initd

@@ -0,0 +1,113 @@
+#!/sbin/runscript
+# Copyright 1999-2005 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Header: $
+
+CUSTOM_VTABLE=" "
+DEFAULT_VTABLE=" "
+VTABLE_PATH=" "
+
+depend()
+{
+  need localmount
+  need logger
+}
+
+
+do_error()
+{
+  # Display an error
+  # $1: Error message
+
+  eerror $1
+  eerror "see http://gentoo-wiki.com/HOWTO_Undervolt_a_Pentium_M_CPU for further information"
+  eend 1
+}
+
+sysfs_check()
+{
+  # Check that the sysfs interface exists
+
+  if [ -e ${VTABLE_PATH_0_3_X} ]; then
+    VTABLE_PATH="${VTABLE_PATH_0_3_X}"
+    CUSTOM_VTABLE="${CUSTOM_VTABLE_0_3_X}"
+    DEFAULT_VTABLE="${DEFAULT_VTABLE_0_3_X}"
+    return 0
+  else
+    if [ -e ${VTABLE_PATH_0_2_X} ]; then
+      VTABLE_PATH="${VTABLE_PATH_0_2_X}"
+      CUSTOM_VTABLE="${CUSTOM_VTABLE_0_2_X}"
+      DEFAULT_VTABLE="${DEFAULT_VTABLE_0_2_X}"
+      return 0
+    else
+      logger "Undervolt: SysFs table not found. Can't modify CPU voltages."
+      eerror "SysFs voltage_table not found. Can't modify CPU voltage table."
+      eerror "It seems that the undervolting patch has not been applied to the kernel"
+      do_error "or that the file /etc/conf.d/undervolt is not correctly configured."
+      return 1
+    fi
+  fi
+}
+
+einfo_tables()
+{
+  # display current table and a custom table
+  # $1 : custom table to display
+
+  # Display the voltage table currently used by the CPU
+  einfo "Current table:     "`cat ${VTABLE_PATH} `
+
+  # Display the custom voltage table
+  einfo "Configured table:  ${1}"
+}
+
+set_custom_table()
+{
+  # Set a custom table through the sysfs interface
+  # $1 : custom table to set
+
+  # Display current table and custom table that will be set
+  einfo_tables "${1}"
+
+  # Write the custom voltage to the SysFS interface and display the
+  # new voltage table that is now used by the CPU if there is no error
+  echo "${1}" > ${VTABLE_PATH} && \
+  einfo "Applied table:     "`cat ${VTABLE_PATH}`
+
+  return $?
+}
+
+start()
+{
+  ebegin "Changing CPU voltages table"
+
+  if [ "$IS_CONFIGURED" = "yes" ]; then
+    sysfs_check || return 1
+
+    set_custom_table "${CUSTOM_VTABLE}"
+    eend $?
+  else
+    do_error "Custom voltage table is not configured. Check the file /etc/conf.d/undervolt"
+  fi
+}
+
+# I think it is not necessary to switch to the default voltage table on shutdown
+# But this init script provides that feature in case you don't agree.
+stop()
+{
+  if [ "$SWITCH_BACK" = "yes" ]; then
+    if [ "$IS_CONFIGURED" = "yes" ]; then
+      ebegin "Switching back to default CPU voltage table"
+
+      sysfs_check || return 1
+
+      set_custom_table "${DEFAULT_VTABLE}"
+      eend $?
+    else
+      do_error "Default voltage table is not configured. Check the file /etc/conf.d/undervolt"
+    fi
+  else
+    ebegin "Not switching back to default CPU voltage table (disabled in configuration)"
+    eend 0
+  fi
+}