1 files changed, 18 insertions, 1 deletions

diff --git a/Documentation/admin-guide/pm/intel_idle.rst b/Documentation/admin-guide/pm/intel_idle.rst
index 8998598746a4..89309e1b0e48 100644
--- a/Documentation/admin-guide/pm/intel_idle.rst
+++ b/Documentation/admin-guide/pm/intel_idle.rst
@@ -168,7 +168,7 @@ and ``idle=nomwait``.  If any of them is present in the kernel command line, the
 ``MWAIT`` instruction is not allowed to be used, so the initialization of
 ``intel_idle`` will fail.
 
-Apart from that there are three module parameters recognized by ``intel_idle``
+Apart from that there are four module parameters recognized by ``intel_idle``
 itself that can be set via the kernel command line (they cannot be updated via
 sysfs, so that is the only way to change their values).
 
@@ -195,6 +195,23 @@ driver ignore the system's ACPI tables entirely or use them for all of the
 recognized processor models, respectively (they both are unset by default and
 ``use_acpi`` has no effect if ``no_acpi`` is set).
 
+The value of the ``states_off`` module parameter (0 by default) represents a
+list of idle states to be disabled by default in the form of a bitmask.
+
+Namely, the positions of the bits that are set in the ``states_off`` value are
+the indices of idle states to be disabled by default (as reflected by the names
+of the corresponding idle state directories in ``sysfs``, :file:`state0`,
+:file:`state1` ... :file:`state<i>` ..., where ``<i>`` is the index of the given
+idle state; see :ref:`idle-states-representation` in :doc:`cpuidle`).
+
+For example, if ``states_off`` is equal to 3, the driver will disable idle
+states 0 and 1 by default, and if it is equal to 8, idle state 3 will be
+disabled by default and so on (bit positions beyond the maximum idle state index
+are ignored).
+
+The idle states disabled this way can be enabled (on a per-CPU basis) from user
+space via ``sysfs``.
+
 
 .. _intel-idle-core-and-package-idle-states: