Initial commit of cc2430 cpu port files. Currently used by /platform/sensinode.

cpu/cc2430/dev/clock.c

@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2009, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * 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 of the Institute 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 INSTITUTE 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 INSTITUTE 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.
+ *
+ * This file is part of the Contiki operating system.
+ *
+ * $Id: clock.c,v 1.1 2009/09/08 20:07:35 zdshelby Exp $
+ */
+
+/**
+ * \file
+ *         Implementation of the clock functions for the 8051 CPU
+ * \author
+ *         Zach Shelby (zach@sensinode.com)
+ */
+
+/**
+ * TODO: Implement clock_fine() and clock_fine_max_ticks() using another timer?
+ */
+
+#include <stdio.h> /*for debug printf*/
+#include "sys/clock.h"
+#include "sys/etimer.h"
+#include "cc2430_sfr.h"
+
+
+/*Sleep timer runs on the 32k RC osc. */
+/* One clock tick is 7.8 ms */
+#define TICK_VAL (32768/128)
+
+#define MAX_TICKS (~((clock_time_t)0) / 2)
+
+/* Used in sleep timer interrupt for calculating the next interrupt time */
+static unsigned long timer_value;
+/*starts calculating the ticks right after reset*/
+static volatile clock_time_t count = 0;
+/*calculates seconds*/
+static volatile clock_time_t seconds = 0;
+
+/*---------------------------------------------------------------------------*/
+/**
+ * One delay is about 0.6 us, so this function delays for len * 0.6 us
+ */
+void
+clock_delay(unsigned int len)
+{
+  unsigned int i;
+  for(i = 0; i< len; i++) {
+    __asm
+      nop
+      __endasm;
+  }
+}
+/*---------------------------------------------------------------------------*/
+/**
+ * Wait for a multiple of ~8 ms (a tick)
+ */
+void
+clock_wait(int i)
+{
+  clock_time_t start;
+
+  start = clock_time();
+  while(clock_time() - start < (clock_time_t)i);
+}
+/*---------------------------------------------------------------------------*/
+clock_time_t
+clock_time(void)
+{
+  return count;
+}
+/*---------------------------------------------------------------------------*/
+CCIF unsigned long
+clock_seconds(void)
+{
+  return seconds;
+}
+/*---------------------------------------------------------------------------*/
+void
+clock_init(void)
+{
+  CLKCON = OSC32K |  TICKSPD2|TICKSPD1|TICKSPD0;	/*tickspeed 250 kHz*/
+  
+  /*Initialize tick value*/
+  timer_value = ST0;									/*sleep timer 0. low bits [7:0]*/
+  timer_value += ((unsigned long int)ST1) << 8;		/*middle bits [15:8]*/
+  timer_value += ((unsigned long int)ST2) << 16;		/*high bits [23:16]*/
+  timer_value += TICK_VAL;							/*init value 256*/
+  ST2 = (unsigned char) (timer_value >> 16);
+  ST1 = (unsigned char) (timer_value >> 8);
+  ST0 = (unsigned char) timer_value;
+  
+  IEN0 |= STIE;		/*interrupt enable for sleep timers. STIE=Interrupt mask, CPU. */
+}
+/*---------------------------------------------------------------------------*/
+void
+cc2430_clock_ISR( void ) __interrupt (ST_VECTOR)
+{
+  IEN0_EA = 0;	/*interrupt disable*/
+  /* When using the cooperative scheduler the timer 2 ISR is only
+     required to increment the RTOS tick count. */
+  
+  /*Read value of the ST0,ST1,ST2 and then add TICK_VAL and write it back.
+    Next interrupt occurs after the current time + TICK_VAL*/
+  timer_value = ST0;
+  timer_value += ((unsigned long int)ST1) << 8;
+  timer_value += ((unsigned long int)ST2) << 16;
+  timer_value += TICK_VAL;
+  ST2 = (unsigned char) (timer_value >> 16);
+  ST1 = (unsigned char) (timer_value >> 8);
+  ST0 = (unsigned char) timer_value;
+  
+  ++count;
+  
+  /* Make sure the CLOCK_CONF_SECOND is a power of two, to ensure
+     that the modulo operation below becomes a logical and and not
+     an expensive divide. Algorithm from Wikipedia:
+     http://en.wikipedia.org/wiki/Power_of_two */
+#if (CLOCK_CONF_SECOND & (CLOCK_CONF_SECOND - 1)) != 0
+#error CLOCK_CONF_SECOND must be a power of two (i.e., 1, 2, 4, 8, 16, 32, 64, ...).
+#error Change CLOCK_CONF_SECOND in contiki-conf.h.
+#endif
+  if(count % CLOCK_CONF_SECOND == 0) {
+    ++seconds;
+  }
+  
+  if(etimer_pending() &&
+     (etimer_next_expiration_time() - count - 1) > MAX_TICKS) {	/*core/sys/etimer.c*/
+    etimer_request_poll();
+  }
+  
+  IRCON &= ~STIF;		/*IRCON.STIF=Sleep timer interrupt flag. This flag called this interrupt func, now reset it*/
+  IEN0_EA = 1;		/*interrupt enable*/
+}
+/*---------------------------------------------------------------------------*/