Add logic to sleep in lpc17xx idle loop

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@3329 42af7a65-404d-4744-a932-0658087f49c3

2 files changed, 108 insertions, 4 deletions

diff --git a/nuttx/arch/arm/src/lpc17xx/Make.defs b/nuttx/arch/arm/src/lpc17xx/Make.defs
index 2b4ea0ffc..3665b9cce 100755
--- a/nuttx/arch/arm/src/lpc17xx/Make.defs
+++ b/nuttx/arch/arm/src/lpc17xx/Make.defs
@@ -1,7 +1,7 @@
 ############################################################################
 # arch/arm/src/lpc17xx/Make.defs
 #
-#   Copyright (C) 2010 Gregory Nutt. All rights reserved.
+#   Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
 #   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
 #
 # Redistribution and use in source and binary forms, with or without
@@ -41,7 +41,7 @@ HEAD_ASRC	= lpc17_vectors.S
 
 CMN_ASRCS	= up_saveusercontext.S up_fullcontextrestore.S up_switchcontext.S
 CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
-		  up_mdelay.c up_udelay.c up_exit.c up_idle.c up_initialize.c \
+		  up_mdelay.c up_udelay.c up_exit.c up_initialize.c \
 		  up_initialstate.c up_interruptcontext.c up_modifyreg8.c \
 		  up_modifyreg16.c up_modifyreg32.c up_releasepending.c \
 		  up_releasestack.c up_reprioritizertr.c up_schedulesigaction.c \
@@ -52,8 +52,8 @@ CMN_CSRCS	= up_assert.c up_blocktask.c up_copystate.c up_createstack.c \
 
 CHIP_ASRCS	=
 CHIP_CSRCS	= lpc17_allocateheap.c lpc17_clockconfig.c lpc17_clrpend.c \
-		  lpc17_gpio.c lpc17_irq.c lpc17_lowputc.c lpc17_serial.c \
-		  lpc17_spi.c lpc17_ssp.c lpc17_start.c lpc17_timerisr.c
+		  lpc17_gpio.c lpc17_idle.c lpc17_irq.c lpc17_lowputc.c \
+		  lpc17_serial.c lpc17_spi.c lpc17_ssp.c lpc17_start.c lpc17_timerisr.c
 
 # Configuration-dependent LPC17xx files
 
diff --git a/nuttx/arch/arm/src/lpc17xx/lpc17_idle.c b/nuttx/arch/arm/src/lpc17xx/lpc17_idle.c
new file mode 100755
index 000000000..6e55bca9e
--- /dev/null
+++ b/nuttx/arch/arm/src/lpc17xx/lpc17_idle.c
@@ -0,0 +1,104 @@
+/****************************************************************************

+ *  arch/arm/src/lpc17/lpc17_idle.c

+ *

+ *   Copyright (C) 2011 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 NuttX 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 <arch/board/board.h>

+#include <nuttx/config.h>

+

+#include <nuttx/arch.h>

+#include "up_internal.h"

+

+/****************************************************************************

+ * Pre-processor Definitions

+ ****************************************************************************/

+

+/* Does the board support an IDLE LED to indicate that the board is in the

+ * IDLE state?

+ */

+

+#if defined(CONFIG_ARCH_LEDS) && defined(LED_IDLE)

+#  define BEGIN_IDLE() up_ledon(LED_IDLE)

+#  define END_IDLE()   up_ledoff(LED_IDLE)

+#else

+#  define BEGIN_IDLE()

+#  define END_IDLE()

+#endif

+

+/****************************************************************************

+ * Private Data

+ ****************************************************************************/

+

+/****************************************************************************

+ * Private Functions

+ ****************************************************************************/

+

+/****************************************************************************

+ * Public Functions

+ ****************************************************************************/

+

+/****************************************************************************

+ * Name: up_idle

+ *

+ * Description:

+ *   up_idle() is the logic that will be executed when their is no other

+ *   ready-to-run task.  This is processor idle time and will continue until

+ *   some interrupt occurs to cause a context switch from the idle task.

+ *

+ *   Processing in this state may be processor-specific. e.g., this is where

+ *   power management operations might be performed.

+ *

+ ****************************************************************************/

+

+void up_idle(void)

+{

+#if defined(CONFIG_SUPPRESS_INTERRUPTS) || defined(CONFIG_SUPPRESS_TIMER_INTS)

+  /* If the system is idle and there are no timer interrupts, then process

+   * "fake" timer interrupts. Hopefully, something will wake up.

+   */

+

+  sched_process_timer();

+#else

+

+  /* Sleep until an interrupt occurs to save power */

+

+  BEGIN_IDLE();

+  asm("WFI");

+  END_IDLE();

+#endif

+}

+