c-user: Move "Idle Task Configuration"

Update #3836.

1 files changed, 96 insertions, 0 deletions

diff --git a/c-user/config/idle-task.rst b/c-user/config/idle-task.rst
new file mode 100644
index 0000000..ef8b192
--- /dev/null
+++ b/c-user/config/idle-task.rst
@@ -0,0 +1,96 @@
+.. SPDX-License-Identifier: CC-BY-SA-4.0
+
+.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR)
+
+Idle Task Configuration
+=======================
+
+This section defines the IDLE task related configuration parameters supported
+by ``<rtems/confdefs.h>``.
+
+.. index:: CONFIGURE_IDLE_TASK_BODY
+
+.. _CONFIGURE_IDLE_TASK_BODY:
+
+CONFIGURE_IDLE_TASK_BODY
+------------------------
+
+CONSTANT:
+    ``CONFIGURE_IDLE_TASK_BODY``
+
+DATA TYPE:
+    Function pointer.
+
+RANGE:
+    Undefined or valid function pointer.
+
+DEFAULT VALUE:
+    This is not defined by default.
+
+DESCRIPTION:
+    ``CONFIGURE_IDLE_TASK_BODY`` is set to the function name corresponding to
+    the application specific IDLE thread body.  If not specified, the BSP or
+    RTEMS default IDLE thread body will be used.
+
+NOTES:
+    None.
+
+.. index:: CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION
+
+.. _CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION:
+
+CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION
+-------------------------------------------
+
+CONSTANT:
+    ``CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION``
+
+DATA TYPE:
+    Boolean feature macro.
+
+RANGE:
+    Defined or undefined.
+
+DEFAULT VALUE:
+    This is not defined by default, the user is assumed to provide one or more
+    initialization tasks.
+
+DESCRIPTION:
+    ``CONFIGURE_IDLE_TASK_INITIALIZES_APPLICATION`` is set to indicate that the
+    user has configured *NO* user initialization tasks or threads and that the
+    user provided IDLE task will perform application initialization and then
+    transform itself into an IDLE task.
+
+NOTES:
+    If you use this option be careful, the user IDLE task *CANNOT* block at all
+    during the initialization sequence.  Further, once application
+    initialization is complete, it must make itself preemptible and enter an
+    IDLE body loop.
+
+    The IDLE task must run at the lowest priority of all tasks in the system.
+
+.. index:: CONFIGURE_IDLE_TASK_STACK_SIZE
+
+.. _CONFIGURE_IDLE_TASK_STACK_SIZE:
+
+CONFIGURE_IDLE_TASK_STACK_SIZE
+------------------------------
+
+CONSTANT:
+    ``CONFIGURE_IDLE_TASK_STACK_SIZE``
+
+DATA TYPE:
+    Unsigned integer (``size_t``).
+
+RANGE:
+    Undefined or positive.
+
+DEFAULT VALUE:
+    The default value is RTEMS_MINIMUM_STACK_SIZE.
+
+DESCRIPTION:
+    ``CONFIGURE_IDLE_TASK_STACK_SIZE`` is set to the desired stack size for the
+    IDLE task.
+
+NOTES:
+    None.