Merge devel code into the trunk.

[tinyos-2.x.git] / tos / chips / atm128 / McuSleepC.nc

diff --git a/tos/chips/atm128/McuSleepC.nc b/tos/chips/atm128/McuSleepC.nc
new file mode 100644 (file)
index 0000000..e85bbd5
--- /dev/null
+++ b/tos/chips/atm128/McuSleepC.nc
@@ -0,0 +1,125 @@
+/// $Id$
+
+/*
+ * "Copyright (c) 2005 Stanford University. All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose, without fee, and without written
+ * agreement is hereby granted, provided that the above copyright
+ * notice, the following two paragraphs and the author appear in all
+ * copies of this software.
+ * 
+ * IN NO EVENT SHALL STANFORD UNIVERSITY BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF STANFORD UNIVERSITY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ * 
+ * STANFORD UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE
+ * PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND STANFORD UNIVERSITY
+ * HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
+ * ENHANCEMENTS, OR MODIFICATIONS."
+ */
+
+/**
+ * Implementation of TEP 112 (Microcontroller Power Management) for
+ * the Atmega128. Power state calculation code copied from Rob
+ * Szewczyk's 1.x code in HPLPowerManagementM.nc.
+ *
+ * <pre>
+ *  $Id$
+ * </pre>
+ *
+ * @author Philip Levis
+ * @author Robert Szewczyk
+ * @date   October 26, 2005
+ */
+
+module McuSleepC {
+  provides {
+    interface McuSleep;
+    interface McuPowerState;
+  }
+  uses {
+    interface McuPowerOverride;
+  }
+}
+implementation {
+  /* There is no dirty bit management because the sleep mode depends on
+     the amount of time remaining in timer0. */
+
+  /* Note that the power values are maintained in an order
+   * based on their active components, NOT on their values.
+   * Look at atm128hardware.h and page 42 of the ATmeg128
+   * manual (figure 17).*/
+  const_uint8_t atm128PowerBits[ATM128_POWER_DOWN + 1] = {
+    0,
+    (1 << SM0),
+    (1 << SM2) | (1 << SM1) | (1 << SM0),
+    (1 << SM1) | (1 << SM0),
+    (1 << SM2) | (1 << SM1),
+    (1 << SM1)};
+    
+  mcu_power_t getPowerState() {
+    uint8_t diff;
+    // Note: we go to sleep even if timer 1, 2, or 3's overflow interrupt
+    // is enabled - this allows using these timers as TinyOS "Alarm"s
+    // while still having power management.
+
+    // Are external timers running?  
+    if (TIMSK & ~(1 << OCIE0 | 1 << TOIE0 | 1 << TOIE1 | 1 << TOIE2) ||
+       ETIMSK & ~(1 << TOIE3)) {
+      return ATM128_POWER_IDLE;
+    }
+    // SPI (Radio stack on mica/micaZ
+    else if (bit_is_set(SPCR, SPIE)) { 
+      return ATM128_POWER_IDLE;
+    }
+    // UARTs are active
+    else if (UCSR0B & (1 << TXCIE | 1 << RXCIE)) { // UART
+      return ATM128_POWER_IDLE;
+    }
+    else if (UCSR1B & (1 << TXCIE | 1 << RXCIE)) { // UART
+      return ATM128_POWER_IDLE;
+    }
+    // ADC is enabled
+    else if (bit_is_set(ADCSR, ADEN)) { 
+      return ATM128_POWER_ADC_NR;
+    }
+    // How soon for the timer to go off?
+    else if (TIMSK & (1 << OCIE0 | 1 << TOIE0)) {
+      // force waiting for timer0 update (overflow glitches otherwise)
+      TCCR0 = TCCR0;
+      while (ASSR & (1 << TCN0UB | 1 << OCR0UB | 1 << TCR0UB))
+       ;
+      diff = OCR0 - TCNT0;
+      if (diff < 16 || TCNT0 > 240) 
+       return ATM128_POWER_EXT_STANDBY;
+      return ATM128_POWER_SAVE;
+    }
+    else {
+      return ATM128_POWER_DOWN;
+    }
+  }
+  
+  async command void McuSleep.sleep() {
+    uint8_t powerState;
+
+    powerState = mcombine(getPowerState(), call McuPowerOverride.lowestState());
+    MCUCR =
+      (MCUCR & 0xe3) | 1 << SE | read_uint8_t(&atm128PowerBits[powerState]);
+
+    sei();
+    asm volatile ("sleep");
+    cli();
+  }
+
+  async command void McuPowerState.update() {
+  }
+
+  default async command mcu_power_t McuPowerOverride.lowestState() {
+    return ATM128_POWER_DOWN;
+  }
+}