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IN NO EVENT SHALL THE COPYRIGHT HOLDER 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. */ #ifndef CSL_TX_SCHEDULER_HPP_ #define CSL_TX_SCHEDULER_HPP_ #include "openthread-core-config.h" #if OPENTHREAD_FTD && OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE #include "common/locator.hpp" #include "common/message.hpp" #include "common/non_copyable.hpp" #include "common/time.hpp" #include "mac/mac.hpp" #include "mac/mac_frame.hpp" #include "thread/indirect_sender_frame_context.hpp" namespace ot { /** * @addtogroup core-mesh-forwarding * * @brief * This module includes definitions for CSL transmission scheduling. * * @{ */ class Child; /** * Implements CSL tx scheduling functionality. * */ class CslTxScheduler : public InstanceLocator, private NonCopyable { friend class Mac::Mac; friend class IndirectSender; public: static constexpr uint8_t kMaxCslTriggeredTxAttempts = OPENTHREAD_CONFIG_MAC_MAX_TX_ATTEMPTS_INDIRECT_POLLS; /** * Defines all the child info required for scheduling CSL transmissions. * * `Child` class publicly inherits from this class. * */ class ChildInfo { public: uint8_t GetCslTxAttempts(void) const { return mCslTxAttempts; } void IncrementCslTxAttempts(void) { mCslTxAttempts++; } void ResetCslTxAttempts(void) { mCslTxAttempts = 0; } bool IsCslSynchronized(void) const { return mCslSynchronized && mCslPeriod > 0; } void SetCslSynchronized(bool aCslSynchronized) { mCslSynchronized = aCslSynchronized; } uint8_t GetCslChannel(void) const { return mCslChannel; } void SetCslChannel(uint8_t aChannel) { mCslChannel = aChannel; } uint32_t GetCslTimeout(void) const { return mCslTimeout; } void SetCslTimeout(uint32_t aTimeout) { mCslTimeout = aTimeout; } uint16_t GetCslPeriod(void) const { return mCslPeriod; } void SetCslPeriod(uint16_t aPeriod) { mCslPeriod = aPeriod; } uint16_t GetCslPhase(void) const { return mCslPhase; } void SetCslPhase(uint16_t aPhase) { mCslPhase = aPhase; } TimeMilli GetCslLastHeard(void) const { return mCslLastHeard; } void SetCslLastHeard(TimeMilli aCslLastHeard) { mCslLastHeard = aCslLastHeard; } uint64_t GetLastRxTimestamp(void) const { return mLastRxTimestamp; } void SetLastRxTimestamp(uint64_t aLastRxTimestamp) { mLastRxTimestamp = aLastRxTimestamp; } private: uint8_t mCslTxAttempts : 7; ///< Number of CSL triggered tx attempts. bool mCslSynchronized : 1; ///< Indicates whether or not the child is CSL synchronized. uint8_t mCslChannel; ///< The channel the device will listen on. uint32_t mCslTimeout; ///< The sync timeout, in seconds. uint16_t mCslPeriod; ///< CSL sampled listening period between consecutive channel samples in units of 10 ///< symbols (160 microseconds). /** * The time in units of 10 symbols from the first symbol of the frame * containing the CSL IE was transmitted until the next channel sample, * see IEEE 802.15.4-2015, section 6.12.2. * * The Thread standard further defines the CSL phase (see Thread 1.4, * section 3.2.6.3.4, also conforming to IEEE 802.15.4-2020, section * 6.12.2.1): * * The "first symbol" from the definition SHALL be interpreted as the * first symbol of the MAC Header. * * "until the next channel sample": * * The CSL Receiver SHALL be ready to receive when the preamble * time T_pa as specified below is reached. * * The CSL Receiver SHOULD be ready to receive earlier than T_pa * and SHOULD stay ready to receive until after the time specified * in CSL Phase, according to the implementation and accuracy * expectations. * * The CSL Transmitter SHALL start transmitting the first symbol * of the preamble of the frame to transmit at the preamble time * T_pa = (CSL-Phase-Time – 192 us) (that is, CCA must be * performed before time T_pa). Here, CSL-Phase-Time is the time * duration specified by the CslPhase field value (in units of 10 * symbol periods). * * This implies that the CSL Transmitter SHALL start transmitting * the first symbol of the MAC Header at the time T_mh = * CSL-Phase-Time. * * Derivation of the next TX timestamp based on this definition and the * RX timestamp of the packet containing the CSL IE: * * Note that RX and TX timestamps are defined to point to the end of the * synchronization header (SHR). * * lastTmh = lastRxTimestamp + phrDuration * * nextTmh = lastTmh + symbolPeriod * 10 * (n * cslPeriod + cslPhase) * = lastTmh + 160us * (n * cslPeriod + cslPhase) * * nextTxTimestamp * = nextTmh - phrDuration * = lastRxTimestamp + 160us * (n * cslPeriod + cslPhase) */ uint16_t mCslPhase; TimeMilli mCslLastHeard; ///< Radio clock time when last frame containing CSL IE was heard. uint64_t mLastRxTimestamp; ///< Radio clock time when last frame containing CSL IE was received, in microseconds. static_assert(kMaxCslTriggeredTxAttempts < (1 << 7), "mCslTxAttempts cannot fit max!"); }; /** * Defines the callbacks used by the `CslTxScheduler`. * */ class Callbacks : public InstanceLocator { friend class CslTxScheduler; private: typedef IndirectSenderBase::FrameContext FrameContext; /** * Initializes the callbacks object. * * @param[in] aInstance A reference to the OpenThread instance. * */ explicit Callbacks(Instance &aInstance); /** * This callback method requests a frame to be prepared for CSL transmission to a given SSED. * * @param[out] aFrame A reference to a MAC frame where the new frame would be placed. * @param[out] aContext A reference to a `FrameContext` where the context for the new frame would be placed. * @param[in] aChild The child for which to prepare the frame. * * @retval kErrorNone Frame was prepared successfully. * @retval kErrorAbort CSL transmission should be aborted (no frame for the child). * */ Error PrepareFrameForChild(Mac::TxFrame &aFrame, FrameContext &aContext, Child &aChild); /** * This callback method notifies the end of CSL frame transmission to a child. * * @param[in] aFrame The transmitted frame. * @param[in] aContext The context associated with the frame when it was prepared. * @param[in] aError kErrorNone when the frame was transmitted successfully, * kErrorNoAck when the frame was transmitted but no ACK was received, * kErrorChannelAccessFailure tx failed due to activity on the channel, * kErrorAbort when transmission was aborted for other reasons. * @param[in] aChild The child to which the frame was transmitted. * */ void HandleSentFrameToChild(const Mac::TxFrame &aFrame, const FrameContext &aContext, Error aError, Child &aChild); }; /** * Initializes the CSL tx scheduler object. * * @param[in] aInstance A reference to the OpenThread instance. * */ explicit CslTxScheduler(Instance &aInstance); /** * Updates the next CSL transmission (finds the nearest child). * * It would then request the `Mac` to do the CSL tx. If the last CSL tx has been fired at `Mac` but hasn't been * done yet, and it's aborted, this method would set `mCslTxChild` to `nullptr` to notify the `HandleTransmitDone` * that the operation has been aborted. * */ void Update(void); /** * Clears all the states inside `CslTxScheduler` and the related states in each child. * */ void Clear(void); /** * Updates the value of `mCslFrameRequestAheadUs`, based on bus speed, bus latency * and `OPENTHREAD_CONFIG_MAC_CSL_REQUEST_AHEAD_US`. * */ void UpdateFrameRequestAhead(void); private: // Guard time in usec to add when checking delay while preparing the CSL frame for tx. static constexpr uint32_t kFramePreparationGuardInterval = 1500; void RescheduleCslTx(void); uint32_t GetNextCslTransmissionDelay(const Child &aChild, uint32_t &aDelayFromLastRx, uint32_t aAheadUs) const; // Callbacks from `Mac` Mac::TxFrame *HandleFrameRequest(Mac::TxFrames &aTxFrames); void HandleSentFrame(const Mac::TxFrame &aFrame, Error aError); void HandleSentFrame(const Mac::TxFrame &aFrame, Error aError, Child &aChild); uint32_t mCslFrameRequestAheadUs; Child *mCslTxChild; Message *mCslTxMessage; Callbacks::FrameContext mFrameContext; Callbacks mCallbacks; }; /** * @} * */ } // namespace ot #endif // OPENTHREAD_FTD && OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE #endif // CSL_TX_SCHEDULER_HPP_