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/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file STM32/can_lld.c
* @brief STM32 CAN subsystem low level driver source.
*
* @addtogroup CAN
* @{
*/
#include "ch.h"
#include "hal.h"
#if CH_HAL_USE_CAN || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/** @brief ADC1 driver identifier.*/
#if STM32_CAN_USE_CAN1 || defined(__DOXYGEN__)
CANDriver CAND1;
#endif
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
/**
* @brief CAN1 TX interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(CAN1_TX_IRQHandler) {
CH_IRQ_PROLOGUE();
/* No more events until a message is transmitted.*/
CAN1->TSR = CAN_TSR_RQCP0 | CAN_TSR_RQCP1 | CAN_TSR_RQCP2;
chSysLockFromIsr();
while (chSemGetCounterI(&CAND1.cd_txsem) < 0)
chSemSignalI(&CAND1.cd_txsem);
chEvtBroadcastI(&CAND1.cd_txempty_event);
chSysUnlockFromIsr();
CH_IRQ_EPILOGUE();
}
/*
* @brief CAN1 RX0 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(CAN1_RX0_IRQHandler) {
uint32_t rf0r;
CH_IRQ_PROLOGUE();
rf0r = CAN1->RF0R;
if ((rf0r & CAN_RF0R_FMP0) > 0) {
/* No more receive events until the queue 0 has been emptied.*/
CAN1->IER &= ~CAN_IER_FMPIE0;
chSysLockFromIsr();
while (chSemGetCounterI(&CAND1.cd_rxsem) < 0)
chSemSignalI(&CAND1.cd_rxsem);
chEvtBroadcastI(&CAND1.cd_rxfull_event);
chSysUnlockFromIsr();
}
if ((rf0r & CAN_RF0R_FOVR0) > 0) {
/* Overflow events handling.*/
CAN1->RF0R = CAN_RF0R_FOVR0;
canAddFlagsI(&CAND1, CAN_OVERFLOW_ERROR);
chSysLockFromIsr();
chEvtBroadcastI(&CAND1.cd_error_event);
chSysUnlockFromIsr();
}
CH_IRQ_EPILOGUE();
}
/**
* @brief CAN1 RX1 interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(CAN1_RX1_IRQHandler) {
CH_IRQ_PROLOGUE();
chSysHalt(); /* Not supported (yet).*/
CH_IRQ_EPILOGUE();
}
/**
* @brief CAN1 SCE interrupt handler.
*
* @isr
*/
CH_IRQ_HANDLER(CAN1_SCE_IRQHandler) {
uint32_t msr;
CH_IRQ_PROLOGUE();
msr = CAN1->MSR;
CAN1->MSR = CAN_MSR_ERRI | CAN_MSR_WKUI | CAN_MSR_SLAKI;
/* Wakeup event.*/
if (msr & CAN_MSR_WKUI) {
chSysLockFromIsr();
chEvtBroadcastI(&CAND1.cd_wakeup_event);
chSysUnlockFromIsr();
}
/* Error event.*/
if (msr & CAN_MSR_ERRI) {
canstatus_t flags;
uint32_t esr = CAN1->ESR;
CAN1->ESR &= ~CAN_ESR_LEC;
flags = (canstatus_t)(esr & 7);
if ((esr & CAN_ESR_LEC) > 0)
flags |= CAN_FRAMING_ERROR;
chSysLockFromIsr();
canAddFlagsI(&CAND1, flags);
chEvtBroadcastI(&CAND1.cd_error_event);
chSysUnlockFromIsr();
}
CH_IRQ_EPILOGUE();
}
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level CAN driver initialization.
*
* @notapi
*/
void can_lld_init(void) {
#if STM32_CAN_USE_CAN1
/* CAN reset, ensures reset state in order to avoid trouble with JTAGs.*/
RCC->APB1RSTR = RCC_APB1RSTR_CAN1RST;
RCC->APB1RSTR = 0;
/* Driver initialization.*/
canObjectInit(&CAND1);
CAND1.cd_can = CAN1;
#endif
}
/**
* @brief Configures and activates the CAN peripheral.
*
* @param[in] canp pointer to the @p CANDriver object
*
* @notapi
*/
void can_lld_start(CANDriver *canp) {
/* Clock activation.*/
#if STM32_CAN_USE_CAN1
if (&CAND1 == canp) {
NVICEnableVector(USB_HP_CAN1_TX_IRQn,
CORTEX_PRIORITY_MASK(STM32_CAN_CAN1_IRQ_PRIORITY));
NVICEnableVector(USB_LP_CAN1_RX0_IRQn,
CORTEX_PRIORITY_MASK(STM32_CAN_CAN1_IRQ_PRIORITY));
NVICEnableVector(CAN1_RX1_IRQn,
CORTEX_PRIORITY_MASK(STM32_CAN_CAN1_IRQ_PRIORITY));
NVICEnableVector(CAN1_SCE_IRQn,
CORTEX_PRIORITY_MASK(STM32_CAN_CAN1_IRQ_PRIORITY));
RCC->APB1ENR |= RCC_APB1ENR_CAN1EN;
}
#endif
/* Entering initialization mode. */
canp->cd_state = CAN_STARTING;
canp->cd_can->MCR = CAN_MCR_INRQ;
while ((canp->cd_can->MSR & CAN_MSR_INAK) == 0)
chThdSleepS(1);
/* BTR initialization.*/
canp->cd_can->BTR = canp->cd_config->cc_btr;
/* MCR initialization.*/
canp->cd_can->MCR = canp->cd_config->cc_mcr;
/* Filters initialization.*/
canp->cd_can->FMR |= CAN_FMR_FINIT;
if (canp->cd_config->cc_num > 0) {
uint32_t i, fmask;
CAN_FilterRegister_TypeDef *cfp;
canp->cd_can->FA1R = 0;
canp->cd_can->FM1R = 0;
canp->cd_can->FS1R = 0;
canp->cd_can->FFA1R = 0;
cfp = canp->cd_can->sFilterRegister;
fmask = 1;
for (i = 0; i < CAN_MAX_FILTERS; i++) {
if (i < canp->cd_config->cc_num) {
if (canp->cd_config->cc_filters[i].cf_mode)
canp->cd_can->FM1R |= fmask;
if (canp->cd_config->cc_filters[i].cf_scale)
canp->cd_can->FS1R |= fmask;
if (canp->cd_config->cc_filters[i].cf_assignment)
canp->cd_can->FFA1R |= fmask;
cfp->FR1 = canp->cd_config->cc_filters[i].cf_register1;
cfp->FR2 = canp->cd_config->cc_filters[i].cf_register2;
canp->cd_can->FA1R |= fmask;
}
else {
cfp->FR1 = 0;
cfp->FR2 = 0;
}
/* Gives a chance for preemption since this is a rather long loop.*/
chSysUnlock();
cfp++;
fmask <<= 1;
chSysLock();
}
}
else {
/* Setup a default filter.*/
canp->cd_can->sFilterRegister[0].FR1 = 0;
canp->cd_can->sFilterRegister[0].FR2 = 0;
canp->cd_can->FM1R = 0;
canp->cd_can->FFA1R = 0;
canp->cd_can->FS1R = 1;
canp->cd_can->FA1R = 1;
}
canp->cd_can->FMR &= ~CAN_FMR_FINIT;
/* Interrupt sources initialization.*/
canp->cd_can->IER = CAN_IER_TMEIE | CAN_IER_FMPIE0 | CAN_IER_FMPIE1 |
CAN_IER_WKUIE | CAN_IER_ERRIE | CAN_IER_LECIE |
CAN_IER_BOFIE | CAN_IER_EPVIE | CAN_IER_EWGIE |
CAN_IER_FOVIE0 | CAN_IER_FOVIE1;
}
/**
* @brief Deactivates the CAN peripheral.
*
* @param[in] canp pointer to the @p CANDriver object
*
* @notapi
*/
void can_lld_stop(CANDriver *canp) {
/* If in ready state then disables the CAN peripheral.*/
if (canp->cd_state == CAN_READY) {
#if STM32_CAN_USE_CAN1
if (&CAND1 == canp) {
CAN1->MCR = 0x00010002; /* Register reset value. */
CAN1->IER = 0x00000000; /* All sources disabled. */
NVICDisableVector(USB_HP_CAN1_TX_IRQn);
NVICDisableVector(USB_LP_CAN1_RX0_IRQn);
NVICDisableVector(CAN1_RX1_IRQn);
NVICDisableVector(CAN1_SCE_IRQn);
RCC->APB1ENR &= ~RCC_APB1ENR_CAN1EN;
}
#endif
}
}
/**
* @brief Determines whether a frame can be transmitted.
*
* @param[in] canp pointer to the @p CANDriver object
*
* @return The queue space availability.
* @retval FALSE no space in the transmit queue.
* @retval TRUE transmit slot available.
*
* @notapi
*/
bool_t can_lld_can_transmit(CANDriver *canp) {
return (canp->cd_can->TSR & CAN_TSR_TME) != 0;
}
/**
* @brief Inserts a frame into the transmit queue.
*
* @param[in] canp pointer to the @p CANDriver object
* @param[in] ctfp pointer to the CAN frame to be transmitted
*
* @notapi
*/
void can_lld_transmit(CANDriver *canp, const CANTxFrame *ctfp) {
uint32_t tir;
CAN_TxMailBox_TypeDef *tmbp;
/* Pointer to a free transmission mailbox.*/
tmbp = &canp->cd_can->sTxMailBox[(canp->cd_can->TSR & CAN_TSR_CODE) >> 24];
/* Preparing the message.*/
if (ctfp->cf_IDE)
tir = ((uint32_t)ctfp->cf_EID << 3) | ((uint32_t)ctfp->cf_RTR << 1) |
CAN_TI0R_IDE;
else
tir = ((uint32_t)ctfp->cf_SID << 21) | ((uint32_t)ctfp->cf_RTR << 1);
tmbp->TDTR = ctfp->cf_DLC;
tmbp->TDLR = ctfp->cf_data32[0];
tmbp->TDHR = ctfp->cf_data32[1];
tmbp->TIR = tir | CAN_TI0R_TXRQ;
}
/**
* @brief Determines whether a frame has been received.
*
* @param[in] canp pointer to the @p CANDriver object
*
* @return The queue space availability.
* @retval FALSE no space in the transmit queue.
* @retval TRUE transmit slot available.
*
* @notapi
*/
bool_t can_lld_can_receive(CANDriver *canp) {
return (canp->cd_can->RF0R & CAN_RF0R_FMP0) > 0;
}
/**
* @brief Receives a frame from the input queue.
*
* @param[in] canp pointer to the @p CANDriver object
* @param[out] crfp pointer to the buffer where the CAN frame is copied
*
* @notapi
*/
void can_lld_receive(CANDriver *canp, CANRxFrame *crfp) {
uint32_t r;
/* Fetches the message.*/
r = canp->cd_can->sFIFOMailBox[0].RIR;
crfp->cf_RTR = (r & CAN_RI0R_RTR) >> 1;
crfp->cf_IDE = (r & CAN_RI0R_IDE) >> 2;
if (crfp->cf_IDE)
crfp->cf_EID = r >> 3;
else
crfp->cf_SID = r >> 21;
r = canp->cd_can->sFIFOMailBox[0].RDTR;
crfp->cf_DLC = r & CAN_RDT0R_DLC;
crfp->cf_FMI = (uint8_t)(r >> 8);
crfp->cf_TIME = (uint16_t)(r >> 16);
crfp->cf_data32[0] = canp->cd_can->sFIFOMailBox[0].RDLR;
crfp->cf_data32[1] = canp->cd_can->sFIFOMailBox[0].RDHR;
/* Releases the mailbox.*/
canp->cd_can->RF0R = CAN_RF0R_RFOM0;
/* If the queue is empty re-enables the interrupt in order to generate
events again.*/
if ((canp->cd_can->RF0R & CAN_RF0R_FMP0) == 0)
canp->cd_can->IER |= CAN_IER_FMPIE0;
}
#if CAN_USE_SLEEP_MODE || defined(__DOXYGEN__)
/**
* @brief Enters the sleep mode.
*
* @param[in] canp pointer to the @p CANDriver object
*
* @notapi
*/
void can_lld_sleep(CANDriver *canp) {
canp->cd_can->MCR |= CAN_MCR_SLEEP;
}
/**
* @brief Enforces leaving the sleep mode.
*
* @param[in] canp pointer to the @p CANDriver object
*
* @notapi
*/
void can_lld_wakeup(CANDriver *canp) {
canp->cd_can->MCR &= ~CAN_MCR_SLEEP;
}
#endif /* CAN_USE_SLEEP_MODE */
#endif /* CH_HAL_USE_CAN */
/** @} */
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