--- /dev/null
+/*
+ * Copyright (c) 2008, Technische Universitaet Berlin
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * - 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.
+ * - Neither the name of the Technische Universitaet Berlin 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.
+ *
+ * - Revision -------------------------------------------------------------
+ * $Revision$
+ * $Date$
+ * @author Jan Hauer <hauer@tkn.tu-berlin.de>
+ * ========================================================================
+ */
+
+#include "TKN154_PHY.h"
+#include "TKN154_MAC.h"
+
+/**
+ * This module is responsible for the transmission/reception of DATA and
+ * COMMAND frames in a nonbeacon-enabled PAN. Its main tasks are initialization
+ * of the parameters of the unslotted CSMA-CA algorithm (NB, BE, etc.),
+ * initiating retransmissions and managing requests for enabling the receiver
+ * for a finite period of time. It does not implement the actual CSMA-CA
+ * algorithm, because due to its timing requirements the CSMA-CA algorithm is
+ * not part of the MAC implementation but of the chip-specific radio driver.
+ */
+
+module DispatchUnslottedCsmaP
+{
+ provides
+ {
+ interface Init as Reset;
+ interface MLME_START;
+ interface FrameTx as FrameTx;
+ interface FrameRx as FrameRx[uint8_t frameType];
+ interface FrameExtracted as FrameExtracted[uint8_t frameType];
+ interface Notify<bool> as WasRxEnabled;
+ }
+ uses
+ {
+ interface Timer<TSymbolIEEE802154> as IndirectTxWaitTimer;
+ interface TransferableResource as RadioToken;
+ interface ResourceRequested as RadioTokenRequested;
+ interface GetNow<token_requested_t> as IsRadioTokenRequested;
+ interface GetNow<bool> as IsRxEnableActive;
+ interface Set<ieee154_macSuperframeOrder_t> as SetMacSuperframeOrder;
+ interface Set<ieee154_macPanCoordinator_t> as SetMacPanCoordinator;
+ interface Get<ieee154_txframe_t*> as GetIndirectTxFrame;
+ interface Notify<bool> as RxEnableStateChange;
+ interface Notify<const void*> as PIBUpdateMacRxOnWhenIdle;
+ interface FrameUtility;
+ interface UnslottedCsmaCa;
+ interface RadioRx;
+ interface RadioOff;
+ interface MLME_GET;
+ interface MLME_SET;
+ interface TimeCalc;
+ interface Leds;
+ }
+}
+implementation
+{
+ typedef enum {
+ SWITCH_OFF,
+ WAIT_FOR_RXDONE,
+ WAIT_FOR_TXDONE,
+ DO_NOTHING,
+ } next_state_t;
+
+ typedef enum {
+ INDIRECT_TX_ALARM,
+ NO_ALARM,
+ } rx_alarm_t;
+
+ /* state / frame management */
+ norace bool m_lock;
+ norace bool m_resume;
+ norace ieee154_txframe_t *m_currentFrame;
+ norace ieee154_txframe_t *m_lastFrame;
+ norace ieee154_macRxOnWhenIdle_t m_macRxOnWhenIdle;
+
+ /* variables for the unslotted CSMA-CA */
+ norace ieee154_csma_t m_csma;
+ norace ieee154_macMaxBE_t m_BE;
+ norace ieee154_macMaxCSMABackoffs_t m_macMaxCSMABackoffs;
+ norace ieee154_macMaxBE_t m_macMaxBE;
+ norace ieee154_macMaxFrameRetries_t m_macMaxFrameRetries;
+ norace ieee154_status_t m_txStatus;
+ norace uint32_t m_transactionTime;
+ norace bool m_indirectTxPending = FALSE;
+
+ /* function / task prototypes */
+ next_state_t tryReceive();
+ next_state_t tryTransmit();
+ next_state_t trySwitchOff();
+ void backupCurrentFrame();
+ void restoreFrameFromBackup();
+ void updateState();
+ void setCurrentFrame(ieee154_txframe_t *frame);
+ void signalTxBroadcastDone(ieee154_txframe_t *frame, ieee154_status_t error);
+ task void signalTxDoneTask();
+ task void wasRxEnabledTask();
+ task void startIndirectTxTimerTask();
+ task void signalStartConfirmTask();
+
+ command error_t Reset.init()
+ {
+ if (m_currentFrame)
+ signal FrameTx.transmitDone(m_currentFrame, IEEE154_TRANSACTION_OVERFLOW);
+ if (m_lastFrame)
+ signal FrameTx.transmitDone(m_lastFrame, IEEE154_TRANSACTION_OVERFLOW);
+ m_currentFrame = m_lastFrame = NULL;
+ call IndirectTxWaitTimer.stop();
+ return SUCCESS;
+ }
+
+ command ieee154_status_t MLME_START.request (
+ uint16_t panID,
+ uint8_t logicalChannel,
+ uint8_t channelPage,
+ uint32_t startTime,
+ uint8_t beaconOrder,
+ uint8_t superframeOrder,
+ bool panCoordinator,
+ bool batteryLifeExtension,
+ bool coordRealignment,
+ ieee154_security_t *coordRealignSecurity,
+ ieee154_security_t *beaconSecurity)
+ {
+ ieee154_status_t status;
+ ieee154_macShortAddress_t shortAddress = call MLME_GET.macShortAddress();
+
+ // check parameters
+ if ((coordRealignSecurity && coordRealignSecurity->SecurityLevel) ||
+ (beaconSecurity && beaconSecurity->SecurityLevel))
+ status = IEEE154_UNSUPPORTED_SECURITY;
+ else if (shortAddress == 0xFFFF)
+ status = IEEE154_NO_SHORT_ADDRESS;
+ else if (logicalChannel > 26 ||
+ (channelPage != IEEE154_SUPPORTED_CHANNELPAGE) ||
+ !(IEEE154_SUPPORTED_CHANNELS & ((uint32_t) 1 << logicalChannel)))
+ status = IEEE154_INVALID_PARAMETER;
+ else if (beaconOrder != 15)
+ status = IEEE154_INVALID_PARAMETER;
+ else {
+ call MLME_SET.macPANId(panID);
+ call MLME_SET.phyCurrentChannel(logicalChannel);
+ call MLME_SET.macBeaconOrder(beaconOrder);
+ call SetMacPanCoordinator.set(panCoordinator);
+ //TODO: check realignment
+ post signalStartConfirmTask();
+ status = IEEE154_SUCCESS;
+ }
+ dbg_serial("DispatchUnslottedCsmaP", "MLME_START.request -> result: %lu\n", (uint32_t) status);
+ return status;
+ }
+
+ task void signalStartConfirmTask()
+ {
+ signal MLME_START.confirm(IEEE154_SUCCESS);
+ }
+
+ command ieee154_status_t FrameTx.transmit(ieee154_txframe_t *frame)
+ {
+ if (m_currentFrame != NULL) {
+ // we've not finished transmitting the current frame yet
+ dbg_serial("DispatchUnslottedCsmaP", "Overflow\n");
+ return IEEE154_TRANSACTION_OVERFLOW;
+ } else {
+ setCurrentFrame(frame);
+ if (call RadioToken.isOwner())
+ updateState();
+ else
+ call RadioToken.request();
+ return IEEE154_SUCCESS;
+ }
+ }
+
+ event void RadioToken.granted()
+ {
+ updateState();
+ }
+
+ void setCurrentFrame(ieee154_txframe_t *frame)
+ {
+ if (frame->header->mhr[MHR_INDEX_FC1] != FC1_FRAMETYPE_BEACON) {
+ // set the sequence number for command/data frame
+ ieee154_macDSN_t dsn = call MLME_GET.macDSN();
+ frame->header->mhr[MHR_INDEX_SEQNO] = dsn++;
+ call MLME_SET.macDSN(dsn);
+ } else {
+ // set the sequence number for beacon frame
+ ieee154_macBSN_t bsn = call MLME_GET.macBSN();
+ frame->header->mhr[MHR_INDEX_SEQNO] = bsn++;
+ call MLME_SET.macBSN(bsn);
+ }
+ m_csma.NB = 0;
+ m_csma.macMaxCsmaBackoffs = m_macMaxCSMABackoffs = call MLME_GET.macMaxCSMABackoffs();
+ m_csma.macMaxBE = m_macMaxBE = call MLME_GET.macMaxBE();
+ m_csma.BE = call MLME_GET.macMinBE();
+ if (call MLME_GET.macBattLifeExt() && m_csma.BE > 2)
+ m_csma.BE = 2;
+ m_BE = m_csma.BE;
+ if (call GetIndirectTxFrame.get() == frame)
+ m_macMaxFrameRetries = 0; // this is an indirect transmissions (never retransmit)
+ else
+ m_macMaxFrameRetries = call MLME_GET.macMaxFrameRetries();
+ m_transactionTime = IEEE154_SHR_DURATION +
+ (frame->headerLen + frame->payloadLen + 2) * IEEE154_SYMBOLS_PER_OCTET; // extra 2 for CRC
+ if (frame->header->mhr[MHR_INDEX_FC1] & FC1_ACK_REQUEST)
+ m_transactionTime += (IEEE154_aTurnaroundTime + IEEE154_aUnitBackoffPeriod +
+ 11 * IEEE154_SYMBOLS_PER_OCTET); // 11 byte for the ACK PPDU
+ // if (frame->headerLen + frame->payloadLen > IEEE154_aMaxSIFSFrameSize)
+ // m_transactionTime += call MLME_GET.macMinLIFSPeriod();
+ // else
+ // m_transactionTime += call MLME_GET.macMinSIFSPeriod();
+ m_currentFrame = frame;
+ }
+
+ /**
+ * The updateState() function is called whenever some event happened that
+ * might require a state transition; it implements a lock mechanism (m_lock)
+ * to prevent race conditions. Whenever the lock is set a "done"-event (from
+ * a RadioTx/RadioRx/RadioOff interface) is pending and will "soon" unset the
+ * lock (and then updateState() will called again). The updateState()
+ * function decides about the next state by checking a list of possible
+ * current states ordered by priority. Calling this function more than
+ * necessary can do no harm.
+ */
+
+ void updateState()
+ {
+ next_state_t next;
+ atomic {
+ // long atomics are bad... but in this block, once the
+ // current state has been determined only one branch will
+ // be taken (there are no loops)
+ if (m_lock || !call RadioToken.isOwner())
+ return;
+ m_lock = TRUE; // lock
+
+ // Check 1: was an indirect transmission successfully started
+ // and are we now waiting for a frame from the coordinator?
+ if (m_indirectTxPending) {
+ next = tryReceive();
+ }
+
+ // Check 2: is some other operation (like MLME-SCAN or MLME-RESET) pending?
+ else if (call IsRadioTokenRequested.getNow()) {
+ if (call RadioOff.isOff()) {
+ // nothing more to do... just release the Token
+ dbg_serial("DispatchUnslottedCsmaP", "Token requested: releasing it.\n");
+ call RadioToken.request(); // we want it back afterwards ...
+ m_lock = FALSE; // unlock
+ call RadioToken.release();
+ return;
+ } else
+ next = SWITCH_OFF;
+ }
+
+ // Check 3: is there a frame ready to transmit?
+ else if (m_currentFrame != NULL) {
+ next = tryTransmit();
+ }
+
+ // Check 4: should we be in receive mode?
+ else if (call IsRxEnableActive.getNow() || m_macRxOnWhenIdle) {
+ next = tryReceive();
+ if (next == DO_NOTHING) {
+ // if there was an active MLME_RX_ENABLE.request then we'll
+ // inform the next higher layer that radio is now in Rx mode
+ post wasRxEnabledTask();
+ }
+ }
+
+ // Check 5: just make sure the radio is switched off
+ else {
+ next = trySwitchOff();
+ if (next == DO_NOTHING) {
+ // nothing more to do... just release the Token
+ m_lock = FALSE; // unlock
+ dbg_serial("DispatchUnslottedCsmaP", "Releasing token\n");
+ call RadioToken.release();
+ return;
+ }
+ }
+
+ // if there is nothing to do, then we must clear the lock
+ if (next == DO_NOTHING)
+ m_lock = FALSE;
+ } // atomic
+
+ // put next state in operation (possibly keeping the lock)
+ switch (next)
+ {
+ case SWITCH_OFF: ASSERT(call RadioOff.off() == SUCCESS); break;
+ case WAIT_FOR_RXDONE: break;
+ case WAIT_FOR_TXDONE: break;
+ case DO_NOTHING: break;
+ }
+ }
+
+ next_state_t tryTransmit()
+ {
+ // tries to transmit m_currentFrame
+ next_state_t next;
+
+ if (!call RadioOff.isOff())
+ next = SWITCH_OFF;
+ else {
+ error_t res;
+ res = call UnslottedCsmaCa.transmit(m_currentFrame, &m_csma);
+ dbg("DispatchUnslottedCsmaP", "UnslottedCsmaCa.transmit() -> %lu\n", (uint32_t) res);
+ next = WAIT_FOR_TXDONE; // this will NOT clear the lock
+ }
+ return next;
+ }
+
+ next_state_t tryReceive()
+ {
+ next_state_t next;
+ if (call RadioRx.isReceiving())
+ next = DO_NOTHING;
+ else if (!call RadioOff.isOff())
+ next = SWITCH_OFF;
+ else {
+ call RadioRx.enableRx(0, 0);
+ next = WAIT_FOR_RXDONE;
+ }
+ return next;
+ }
+
+ next_state_t trySwitchOff()
+ {
+ next_state_t next;
+ if (call RadioOff.isOff())
+ next = DO_NOTHING;
+ else
+ next = SWITCH_OFF;
+ return next;
+ }
+
+ async event void RadioOff.offDone()
+ {
+ m_lock = FALSE;
+ updateState();
+ }
+
+ async event void RadioRx.enableRxDone()
+ {
+ if (m_indirectTxPending) // indirect transmission, now waiting for data
+ post startIndirectTxTimerTask();
+ m_lock = FALSE;
+ updateState();
+ }
+
+ event void RxEnableStateChange.notify(bool whatever)
+ {
+ if (!call RadioToken.isOwner())
+ call RadioToken.request();
+ else
+ updateState();
+ }
+
+ event void PIBUpdateMacRxOnWhenIdle.notify( const void* val )
+ {
+ atomic m_macRxOnWhenIdle = *((ieee154_macRxOnWhenIdle_t*) val);
+ signal RxEnableStateChange.notify(TRUE);
+ }
+
+ event void IndirectTxWaitTimer.fired()
+ {
+ atomic {
+ if (m_indirectTxPending) {
+ m_indirectTxPending = FALSE;
+ post signalTxDoneTask();
+ }
+ }
+ }
+
+ task void startIndirectTxTimerTask()
+ {
+ call IndirectTxWaitTimer.startOneShot(call MLME_GET.macMaxFrameTotalWaitTime());
+ }
+
+ async event void UnslottedCsmaCa.transmitDone(ieee154_txframe_t *frame,
+ ieee154_csma_t *csma, bool ackPendingFlag, error_t result)
+ {
+ bool done = TRUE;
+ dbg("DispatchUnslottedCsmaP", "UnslottedCsmaCa.transmitDone() -> %lu\n", (uint32_t) result);
+ m_resume = FALSE;
+
+ switch (result)
+ {
+ case SUCCESS:
+ // frame was successfully transmitted, if ACK was requested
+ // then a matching ACK was successfully received as well
+ m_txStatus = IEEE154_SUCCESS;
+ if (frame->payload[0] == CMD_FRAME_DATA_REQUEST &&
+ ((frame->header->mhr[MHR_INDEX_FC1]) & FC1_FRAMETYPE_MASK) == FC1_FRAMETYPE_CMD) {
+ // this was a data request frame
+ m_txStatus = IEEE154_NO_DATA; // pessimistic
+ if (ackPendingFlag) {
+ // the coordinator has data for us; switch to Rx
+ // to complete the indirect transmission
+ m_indirectTxPending = TRUE;
+ m_lastFrame = m_currentFrame;
+ m_currentFrame = NULL;
+ ASSERT(call RadioRx.enableRx(0, 0) == SUCCESS);
+ return;
+ }
+ }
+ break;
+ case FAIL:
+ // The CSMA-CA algorithm failed: the frame was not transmitted,
+ // because channel was never idle
+ m_txStatus = IEEE154_CHANNEL_ACCESS_FAILURE;
+ break;
+ case ENOACK:
+ // frame was transmitted, but we didn't receive an ACK (although
+ // we requested an one). note: coordinator never retransmits an
+ // indirect transmission (see above)
+ if (m_macMaxFrameRetries > 0) {
+ // retransmit: reinitialize CSMA-CA parameters
+ done = FALSE;
+ m_csma.NB = 0;
+ m_csma.macMaxCsmaBackoffs = m_macMaxCSMABackoffs;
+ m_csma.macMaxBE = m_macMaxBE;
+ m_csma.BE = m_BE;
+ m_macMaxFrameRetries -= 1;
+ } else
+ m_txStatus = IEEE154_NO_ACK;
+ break;
+ default:
+ ASSERT(0);
+ break;
+ }
+
+ if (done) {
+ m_lastFrame = m_currentFrame;
+ m_currentFrame = NULL;
+ post signalTxDoneTask();
+ }
+
+ m_lock = FALSE;
+ updateState();
+ }
+
+ task void signalTxDoneTask()
+ {
+ ieee154_txframe_t *lastFrame = m_lastFrame;
+ ieee154_status_t status = m_txStatus;
+ m_indirectTxPending = FALSE;
+ m_lastFrame = NULL; // only now the next transmission can begin
+ if (lastFrame) {
+ dbg("DispatchUnslottedCsmaP", "Transmit done, DSN: %lu, result: 0x%lx\n",
+ (uint32_t) MHR(lastFrame)[MHR_INDEX_SEQNO], (uint32_t) status);
+ signal FrameTx.transmitDone(lastFrame, status);
+ }
+ updateState();
+ }
+
+ event message_t* RadioRx.received(message_t* frame, const ieee154_timestamp_t *timestamp)
+ {
+ // received a frame -> find out frame type and
+ // signal it to responsible client component
+ uint8_t *payload = (uint8_t *) frame->data;
+ uint8_t *mhr = MHR(frame);
+ uint8_t frameType = mhr[MHR_INDEX_FC1] & FC1_FRAMETYPE_MASK;
+
+ if (frameType == FC1_FRAMETYPE_CMD)
+ frameType += payload[0];
+ dbg("DispatchUnslottedCsmaP", "Received frame, DSN: %lu, type: 0x%lu\n",
+ (uint32_t) mhr[MHR_INDEX_SEQNO], (uint32_t) frameType);
+ atomic {
+ if (m_indirectTxPending) {
+ message_t* frameBuf;
+ call IndirectTxWaitTimer.stop();
+ // TODO: check!
+ //if (frame->payloadLen)
+ // is this frame from our coordinator? hmm... we cannot say
+ // with certainty, because we might only know either the
+ // coordinator extended or short address (and the frame could
+ // have been sent with the other addressing mode) ??
+ m_txStatus = IEEE154_SUCCESS;
+ frameBuf = signal FrameExtracted.received[frameType](frame, m_lastFrame);
+ signal IndirectTxWaitTimer.fired();
+ return frameBuf;
+ } else
+ return signal FrameRx.received[frameType](frame);
+ }
+ }
+
+ task void wasRxEnabledTask()
+ {
+ signal WasRxEnabled.notify(TRUE);
+ }
+
+
+ default event void FrameTx.transmitDone(ieee154_txframe_t *data, ieee154_status_t status) {}
+ default event message_t* FrameRx.received[uint8_t client](message_t* data) {return data;}
+ default async command bool IsRxEnableActive.getNow() {return FALSE;}
+
+ default event message_t* FrameExtracted.received[uint8_t client](message_t* msg, ieee154_txframe_t *txFrame) {return msg;}
+
+ command error_t WasRxEnabled.enable() {return FAIL;}
+ command error_t WasRxEnabled.disable() {return FAIL;}
+ default event void MLME_START.confirm(ieee154_status_t status) {}
+ async event void RadioToken.transferredFrom(uint8_t fromClientID) {ASSERT(0);}
+ async event void RadioTokenRequested.requested(){ updateState(); }
+ async event void RadioTokenRequested.immediateRequested(){ updateState(); }
+}
projects / tinyos-2.x.git / blobdiff