Hellen says serial can

This commit is contained in:
rusefi 2020-09-07 12:10:39 -04:00
parent adcf368cc9
commit 05ef53fbbc
2 changed files with 335 additions and 0 deletions

View File

@ -0,0 +1,268 @@
/**
* @file serial_can.cpp
*
* This code is a bridge between a serial streaming used by TS and a packet-frame CAN-bus, using the ISO-TP protocol.
* ISO 15765-2, or ISO-TP (Transport Layer), which is an international standard for sending data packets over a CAN-Bus.
* https://en.wikipedia.org/wiki/ISO_15765-2
*
* @date Aug 1, 2020
* @author andreika <prometheus.pcb@gmail.com>
* @author Andrey Belomutskiy, (c) 2012-2020
*/
#include "global.h"
#include "os_access.h"
#include "serial_can.h"
static CanStreamerState state;
int CanStreamerState::sendFrame(CANDriver *canp, const IsoTpFrameHeader & header, const uint8_t *data, int num) {
CANTxFrame txmsg;
memset(&txmsg, 0, sizeof(txmsg));
txmsg.IDE = CAN_IDE_STD;
txmsg.EID = CAN_TX_ID;
txmsg.RTR = CAN_RTR_DATA;
txmsg.DLC = 8; // 8 bytes
// fill the frame data according to the CAN-TP protocol (ISO 15765-2)
txmsg.data8[0] = (uint8_t)((header.frameType & 0xf) << 4);
int offset, maxNumBytes;
switch (header.frameType) {
case ISO_TP_FRAME_SINGLE:
offset = 1;
maxNumBytes = minI(header.numBytes, txmsg.DLC - offset);
txmsg.data8[0] |= maxNumBytes;
break;
case ISO_TP_FRAME_FIRST:
txmsg.data8[0] |= (header.numBytes >> 8) & 0xf;
txmsg.data8[1] = (uint8_t)(header.numBytes & 0xff);
offset = 2;
maxNumBytes = minI(header.numBytes, txmsg.DLC - offset);
break;
case ISO_TP_FRAME_CONSECUTIVE:
txmsg.data8[0] |= header.index & 0xf;
offset = 1;
maxNumBytes = txmsg.DLC - offset;
break;
case ISO_TP_FRAME_FLOW_CONTROL:
txmsg.data8[0] |= header.fcFlag & 0xf;
txmsg.data8[1] = (uint8_t)(header.blockSize);
txmsg.data8[2] = (uint8_t)(header.separationTime);
offset = 3;
maxNumBytes = 0; // no data is sent with 'flow control' frame
break;
}
int numBytes = minI(maxNumBytes, num);
// copy the contents
if (data != nullptr) {
for (int i = 0; i < numBytes; i++) {
txmsg.data8[i + offset] = data[i];
}
}
// send the frame!
if (canTransmit(&CAND1, CAN_ANY_MAILBOX, &txmsg, TIME_MS2I(100)) == MSG_OK)
return numBytes;
return 0;
}
// returns the number of copied bytes
int CanStreamerState::receiveFrame(CANDriver *canp, CANRxFrame *rxmsg, uint8_t *buf, int num) {
if (rxmsg == nullptr || rxmsg->DLC < 1)
return 0;
int frameType = (rxmsg->data8[0] >> 4) & 0xf;
int numBytesAvailable, frameIdx;
uint8_t *srcBuf = rxmsg->data8;
switch (frameType) {
case ISO_TP_FRAME_SINGLE:
numBytesAvailable = rxmsg->data8[0] & 0xf;
srcBuf = rxmsg->data8 + 1;
this->waitingForNumBytes = -1;
break;
case ISO_TP_FRAME_FIRST:
this->waitingForNumBytes = ((rxmsg->data8[0] & 0xf) << 8) | rxmsg->data8[1];
this->waitingForFrameIndex = 1;
numBytesAvailable = minI(this->waitingForNumBytes, 6);
srcBuf = rxmsg->data8 + 2;
break;
case ISO_TP_FRAME_CONSECUTIVE:
frameIdx = rxmsg->data8[0] & 0xf;
if (this->waitingForNumBytes < 0 || this->waitingForFrameIndex != frameIdx) {
// todo: that's an abnormal situation, and we probably should react?
return 0;
}
numBytesAvailable = minI(this->waitingForNumBytes, 7);
srcBuf = rxmsg->data8 + 1;
this->waitingForFrameIndex = (this->waitingForFrameIndex + 1) & 0xf;
break;
case ISO_TP_FRAME_FLOW_CONTROL:
// todo: currently we just ignore the FC frame
return 0;
}
#if defined(TS_CAN_DEVICE_SHORT_PACKETS_IN_ONE_FRAME)
if (frameType == ISO_TP_FRAME_SINGLE) {
srcBuf = state.tmpRxBuf;
// restore the CRC on the whole packet
uint32_t crc = crc32((void *) (rxmsg->data + 1), numBytesAvailable);
// we need a separate buffer for crc because srcBuf may not be word-aligned for direct copy
uint8_t crcBuffer[sizeof(uint32_t)];
*(uint32_t *) (crcBuffer) = SWAP_UINT32(crc);
// now set the packet size (including the command byte)
*(uint16_t *) srcBuf = SWAP_UINT16(numBytesAvailable);
// copy the data
if (numBytesAvailable > 0)
memcpy(srcBuf + 2, rxmsg->data8 + 1, numBytesAvailable);
// copy the crc
memcpy(srcBuf + 2 + numBytesAvailable, crcBuffer, sizeof(crcBuffer));
numBytesAvailable += 1 + sizeof(crcBuffer); // added command & crc bytes
}
#endif /* TS_CAN_DEVICE_SHORT_PACKETS_IN_ONE_FRAME */
int numBytesToCopy = minI(num, numBytesAvailable);
if (buf != nullptr) {
memcpy(buf, srcBuf, numBytesToCopy);
}
srcBuf += numBytesToCopy;
numBytesAvailable -= numBytesToCopy;
waitingForNumBytes -= numBytesToCopy;
// if there are some more bytes left, we save them for the next time
for (int i = 0; i < numBytesAvailable; i++) {
rxFifoBuf.put(srcBuf[i]);
}
// according to the specs, we need to acknowledge the received multi-frame start frame
if (frameType == ISO_TP_FRAME_FIRST) {
IsoTpFrameHeader header;
header.frameType = ISO_TP_FRAME_FLOW_CONTROL;
header.fcFlag = 0; // = "continue to send"
header.blockSize = 0; // = the remaining "frames" to be sent without flow control or delay
header.separationTime = 0; // = wait 0 milliseconds, send immediately
sendFrame(canp, header, nullptr, 0);
}
return numBytesToCopy;
}
int CanStreamerState::sendDataTimeout(CANDriver *canp, const uint8_t *txbuf, int numBytes, sysinterval_t timeout) {
int offset = 0;
msg_t ret;
// 1 frame
if (numBytes <= 7) {
IsoTpFrameHeader header;
header.frameType = ISO_TP_FRAME_SINGLE;
header.numBytes = numBytes;
return state.sendFrame(canp, header, txbuf, numBytes);
}
// multiple frames
// send the first header frame
IsoTpFrameHeader header;
header.frameType = ISO_TP_FRAME_FIRST;
header.numBytes = numBytes;
int numSent = state.sendFrame(canp, header, txbuf + offset, numBytes);
offset += numSent;
numBytes -= numSent;
int totalNumSent = numSent;
// get a flow control frame
CANRxFrame rxmsg;
if (canReceive(&CAND1, CAN_ANY_MAILBOX, &rxmsg, timeout) == MSG_OK) {
state.receiveFrame(canp, &rxmsg, nullptr, 0);
}
// send the rest of the data
int idx = 1;
while (numBytes > 0) {
int len = minI(numBytes, 7);
// send the consecutive frames
IsoTpFrameHeader header;
header.frameType = ISO_TP_FRAME_CONSECUTIVE;
header.index = ((idx++) & 0x0f);
header.numBytes = numBytes;
int numSent = state.sendFrame(canp, header, txbuf + offset, numBytes);
if (numSent < 1)
break;
totalNumSent += numSent;
offset += numSent;
numBytes -= numSent;
}
return totalNumSent;
}
int CanStreamerState::getDataFromFifo(uint8_t *rxbuf, size_t &numBytes) {
if (rxFifoBuf.isEmpty())
return 0;
int numReadFromFifo = minI(numBytes, rxFifoBuf.getCount());
// move bytes from the FIFO buffer
int i;
for (i = 0; !rxFifoBuf.isEmpty() && i < numReadFromFifo; i++) {
rxbuf[i] = rxFifoBuf.get();
numBytes--;
}
return i;
}
void canInit(CANDriver *canp) {
chEvtRegister(&CAND1.rxfull_event, &state.el, 0);
}
msg_t canAddToTxStreamTimeout(CANDriver *canp, size_t *np,
const uint8_t *txbuf, sysinterval_t timeout) {
int numBytes = *np;
int offset = 0;
int minNumBytesRequiredToSend = 7 - state.txFifoBuf.getCount();
while (numBytes >= minNumBytesRequiredToSend) {
state.txFifoBuf.put(txbuf + offset, minNumBytesRequiredToSend);
int numSent = state.sendDataTimeout(canp, (const uint8_t *)state.txFifoBuf.elements, state.txFifoBuf.getCount(), timeout);
if (numSent < 1)
break;
state.txFifoBuf.clear();
offset += numSent;
numBytes -= numSent;
minNumBytesRequiredToSend = 7;
}
// now we put the rest on hold
state.txFifoBuf.put(txbuf + offset, numBytes);
return MSG_OK;
}
msg_t canFlushTxStream(CANDriver *canp, sysinterval_t timeout) {
int numSent = state.sendDataTimeout(canp, (const uint8_t *)state.txFifoBuf.elements, state.txFifoBuf.getCount(), timeout);
state.txFifoBuf.clear();
return MSG_OK;
}
msg_t canStreamReceiveTimeout(CANDriver *canp, size_t *np,
uint8_t *rxbuf, sysinterval_t timeout) {
int i = 0;
size_t numBytes = *np;
// first, fill the data from the stored buffer (saved from the previous CAN frame)
i = state.getDataFromFifo(rxbuf, numBytes);
// if even more data is needed, then we receive more CAN frames
while (numBytes > 0) {
if (chEvtWaitAnyTimeout(ALL_EVENTS, timeout) == 0)
return MSG_TIMEOUT;
CANRxFrame rxmsg;
if (canReceive(&CAND1, CAN_ANY_MAILBOX, &rxmsg, TIME_IMMEDIATE) == MSG_OK) {
int numReceived = state.receiveFrame(canp, &rxmsg, rxbuf + i, numBytes);
if (numReceived < 1)
break;
numBytes -= numReceived;
}
}
//*np -= numBytes;
return MSG_OK;
}

View File

@ -0,0 +1,67 @@
/**
* @file serial_can.h
*
* @date Aug 1, 2020
* @author andreika <prometheus.pcb@gmail.com>
* @author Andrey Belomutskiy, (c) 2012-2020
*/
#pragma once
#include "fifo_buffer.h"
#define CAN_TX_ID 0x102
enum IsoTpFrameType {
ISO_TP_FRAME_SINGLE = 0,
ISO_TP_FRAME_FIRST = 1,
ISO_TP_FRAME_CONSECUTIVE = 2,
ISO_TP_FRAME_FLOW_CONTROL = 3,
};
class IsoTpFrameHeader {
public:
IsoTpFrameType frameType;
// used for 'single' or 'first' frames
int numBytes;
// used for 'consecutive' frames
int index;
// used for 'flow control' frames
int fcFlag;
int blockSize;
int separationTime;
};
class CanStreamerState {
public:
fifo_buffer<uint8_t, 64> rxFifoBuf;
fifo_buffer<uint8_t, 64> txFifoBuf;
#if defined(TS_CAN_DEVICE_SHORT_PACKETS_IN_ONE_FRAME)
// used to restore the original packet with CRC
uint8_t tmpRxBuf[13];
#endif
// used for multi-frame ISO-TP packets
int waitingForNumBytes = 0;
int waitingForFrameIndex = 0;
event_listener_t el;
public:
int sendFrame(CANDriver *canp, const IsoTpFrameHeader & header, const uint8_t *data, int num);
int receiveFrame(CANDriver *canp, CANRxFrame *rxmsg, uint8_t *buf, int num);
int getDataFromFifo(uint8_t *rxbuf, size_t &numBytes);
// returns the number of bytes sent
int sendDataTimeout(CANDriver *canp, const uint8_t *txbuf, int numBytes, sysinterval_t timeout);
};
void canInit(CANDriver *canp);
// we don't have canStreamSendTimeout() because we need to "bufferize" the stream and send it in fixed-length packets
msg_t canAddToTxStreamTimeout(CANDriver *canp, size_t *np, const uint8_t *txbuf, sysinterval_t timeout);
msg_t canFlushTxStream(CANDriver *canp, sysinterval_t timeout);
msg_t canStreamReceiveTimeout(CANDriver *canp, size_t *np, uint8_t *rxbuf, sysinterval_t timeout);