NuttX RTOS

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3 42af7a65-404d-4744-a932-0658087f49c3

1 files changed, 136 insertions, 0 deletions

diff --git a/nuttx/sched/wd_initialize.c b/nuttx/sched/wd_initialize.c
new file mode 100644
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+/************************************************************
+ * wd_initialize.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <sys/types.h>
+#include <queue.h>
+#include <nuttx/kmalloc.h>
+#include "os_internal.h"
+#include "wd_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Type Declarations
+ ************************************************************/
+
+/************************************************************
+ * Global Variables
+ ************************************************************/
+
+/* The g_wdfreelist data structure is a singly linked list
+ * of watchdogs available to the system for delayed function
+ * use.
+ */
+
+sq_queue_t g_wdfreelist;
+
+/* g_wdpool is a pointer to a list of pre-allocated watchdogs.
+ * The number of watchdogs in the pool is a configuration
+ * item.
+ */
+
+wdog_t *g_wdpool;
+
+/* The g_wdactivelist data structure is a singly linked list
+ * ordered by watchdog expiration time. When watchdog timers
+ * expire,the functions on this linked list are removed and
+ * the function is called.
+ */
+
+sq_queue_t g_wdactivelist;
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Function:  wd_initialize
+ *
+ * Description:
+ * This function initalized the watchdog data structures
+ *
+ * Parameters:
+ *   None
+ *
+ * Return Value:
+ *   None
+ *
+ * Assumptions:
+ *   This function must be called early in the initialization
+ *   sequence before the timer interrupt is attached and
+ *   before any watchdog services are used.
+ *
+ ************************************************************/
+
+void wd_initialize(void)
+{
+  /* Initialize the free watchdog list */
+
+  sq_init(&g_wdfreelist);
+
+  /* The g_wdfreelist must be loaded at initialization time to hold the
+   * configured number of watchdogs.
+   */
+
+  g_wdpool = (wdog_t*)kmalloc(sizeof(wdog_t) * CONFIG_PREALLOC_WDOGS);
+  if (g_wdpool)
+    {
+      wdog_t *wdog = g_wdpool;
+      int i;
+
+      for (i = 0; i < CONFIG_PREALLOC_WDOGS; i++)
+        {
+          sq_addlast((sq_entry_t*)wdog++, &g_wdfreelist);
+        }
+    }
+
+  /* The g_wdactivelist queue must be reset at initialization time. */
+
+  sq_init(&g_wdactivelist);
+}