tinySA/os/hal/platforms/SPC5xx/LINFlex_v1/serial_lld.c

/*
 * Licensed under ST Liberty SW License Agreement V2, (the "License");
 * You may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *        http://www.st.com/software_license_agreement_liberty_v2
 *
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the License is distributed on an "AS IS" BASIS, 
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file    SPC5xx/serial_lld.c
 * @brief   SPC5xx low level serial driver code.
 *
 * @addtogroup SERIAL
 * @{
 */

#include "ch.h"
#include "hal.h"

#if HAL_USE_SERIAL || defined(__DOXYGEN__)

/*===========================================================================*/
/* Driver exported variables.                                                */
/*===========================================================================*/

/**
 * @brief   LIINFlex-0 serial driver identifier.
 */
#if SPC5_SERIAL_USE_LINFLEX0 || defined(__DOXYGEN__)
SerialDriver SD1;
#endif

/**
 * @brief   LIINFlex-1 serial driver identifier.
 */
#if SPC5_SERIAL_USE_LINFLEX1 || defined(__DOXYGEN__)
SerialDriver SD2;
#endif

/**
 * @brief   LIINFlex-2 serial driver identifier.
 */
#if SPC5_SERIAL_USE_LINFLEX2 || defined(__DOXYGEN__)
SerialDriver SD3;
#endif

/**
 * @brief   LIINFlex-3 serial driver identifier.
 */
#if SPC5_SERIAL_USE_LINFLEX3 || defined(__DOXYGEN__)
SerialDriver SD4;
#endif

/*===========================================================================*/
/* Driver local variables.                                                   */
/*===========================================================================*/

/**
 * @brief   Driver default configuration.
 */
static const SerialConfig default_config = {
  SERIAL_DEFAULT_BITRATE,
  SD_MODE_8BITS_PARITY_NONE
};

/*===========================================================================*/
/* Driver local functions.                                                   */
/*===========================================================================*/

/**
 * @brief   LINFlex initialization.
 * @details This function must be invoked with interrupts disabled.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 * @param[in] config    the architecture-dependent serial driver configuration
 */
static void spc5_linflex_init(SerialDriver *sdp, const SerialConfig *config) {
  uint32_t div;
  volatile struct LINFLEX_tag *linflexp = sdp->linflexp;

  /* Enters the configuration mode.*/
  linflexp->LINCR1.R  = 1;                      /* INIT bit.                */

  /* Configures the LINFlex in UART mode with all the required
     parameters.*/
  linflexp->UARTCR.R  = SPC5_UARTCR_UART;       /* UART mode FIRST.         */
  linflexp->UARTCR.R  = SPC5_UARTCR_UART | SPC5_UARTCR_RXEN | config->mode;
  div = halSPCGetSystemClock() / config->speed;
  linflexp->LINFBRR.R = (uint16_t)(div & 15);   /* Fractional divider.      */
  linflexp->LINIBRR.R = (uint16_t)(div >> 4);   /* Integer divider.         */
  linflexp->UARTSR.R  = 0xFFFF;                 /* Clearing UARTSR register.*/
  linflexp->LINIER.R  = SPC5_LINIER_DTIE | SPC5_LINIER_DRIE |
                        SPC5_LINIER_BOIE | SPC5_LINIER_FEIE |
                        SPC5_LINIER_SZIE;       /* Interrupts enabled.      */

  /* Leaves the configuration mode.*/
  linflexp->LINCR1.R  = 0;
}

/**
 * @brief   LINFlex de-initialization.
 * @details This function must be invoked with interrupts disabled.
 *
 * @param[in] linflexp  pointer to a LINFlex I/O block
 */
static void spc5_linflex_deinit(volatile struct LINFLEX_tag *linflexp) {

  /* Enters the configuration mode.*/
  linflexp->LINCR1.R  = 1;                      /* INIT bit.                */

  /* Resets the LINFlex registers.*/
  linflexp->LINFBRR.R = 0;                      /* Fractional divider.      */
  linflexp->LINIBRR.R = 0;                      /* Integer divider.         */
  linflexp->UARTSR.R  = 0xFFFF;                 /* Clearing UARTSR register.*/
  linflexp->UARTCR.R  = SPC5_UARTCR_UART;
  linflexp->LINIER.R  = 0;                      /* Interrupts disabled.     */

  /* Leaves the configuration mode.*/
  linflexp->LINCR1.R  = 0;
}

/**
 * @brief   Common RXI IRQ handler.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 */
static void spc5xx_serve_rxi_interrupt(SerialDriver *sdp) {
  flagsmask_t sts = 0;
  uint16_t sr = sdp->linflexp->UARTSR.R;

  sdp->linflexp->UARTSR.R = SPC5_UARTSR_NF | SPC5_UARTSR_DRF |
                            SPC5_UARTSR_PE0;
  if (sr & SPC5_UARTSR_NF)
    sts |= SD_NOISE_ERROR;
  if (sr & SPC5_UARTSR_PE0)
    sts |= SD_PARITY_ERROR;
  if (sts) {
    chSysLockFromIsr();
    chnAddFlagsI(sdp, sts);
    chSysUnlockFromIsr();
  }
  if (sr & SPC5_UARTSR_DRF) {
     sdIncomingDataI(sdp, sdp->linflexp->BDRM.B.DATA4);
     sdp->linflexp->UARTSR.R = SPC5_UARTSR_RMB;
  }
}

/**
 * @brief   Common TXI IRQ handler.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 */
static void spc5xx_serve_txi_interrupt(SerialDriver *sdp) {
  msg_t b;

  sdp->linflexp->UARTSR.R = SPC5_UARTSR_DTF;
  b = chOQGetI(&sdp->oqueue);
  if (b < Q_OK) {
    chnAddFlagsI(sdp, CHN_OUTPUT_EMPTY);
    sdp->linflexp->UARTCR.B.TXEN = 0;
  }
  else
    sdp->linflexp->BDRL.B.DATA0 = b;
}

/**
 * @brief   Common ERR IRQ handler.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 */
static void spc5xx_serve_err_interrupt(SerialDriver *sdp) {
  flagsmask_t sts = 0;
  uint16_t sr = sdp->linflexp->UARTSR.R;

  sdp->linflexp->UARTSR.R = SPC5_UARTSR_BOF | SPC5_UARTSR_FEF |
                            SPC5_UARTSR_SZF;
  if (sr & SPC5_UARTSR_BOF)
    sts |= SD_OVERRUN_ERROR;
  if (sr & SPC5_UARTSR_FEF)
    sts |= SD_FRAMING_ERROR;
  if (sr & SPC5_UARTSR_SZF)
    sts |= SD_BREAK_DETECTED;
  chSysLockFromIsr();
  chnAddFlagsI(sdp, sts);
  chSysUnlockFromIsr();
}

#if SPC5_SERIAL_USE_LINFLEX0 || defined(__DOXYGEN__)
static void notify1(GenericQueue *qp) {

  (void)qp;
  if (!SD1.linflexp->UARTCR.B.TXEN) {
    msg_t b = sdRequestDataI(&SD1);
    if (b != Q_EMPTY) {
      SD1.linflexp->UARTCR.B.TXEN = 1;
      SD1.linflexp->BDRL.B.DATA0 = b;
    }
  }
}
#endif

#if SPC5_SERIAL_USE_LINFLEX1 || defined(__DOXYGEN__)
static void notify2(GenericQueue *qp) {

  (void)qp;
  if (!SD2.linflexp->UARTCR.B.TXEN) {
    msg_t b = sdRequestDataI(&SD2);
    if (b != Q_EMPTY) {
      SD2.linflexp->UARTCR.B.TXEN = 1;
      SD2.linflexp->BDRL.B.DATA0 = b;
    }
  }
}
#endif

/*===========================================================================*/
/* Driver interrupt handlers.                                                */
/*===========================================================================*/

#if SPC5_SERIAL_USE_LINFLEX0 || defined(__DOXYGEN__)
/**
 * @brief   LINFlex-0 RXI interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(SPC5_LINFLEX0_RXI_HANDLER) {

  CH_IRQ_PROLOGUE();

  spc5xx_serve_rxi_interrupt(&SD1);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   LINFlex-0 TXI interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(SPC5_LINFLEX0_TXI_HANDLER) {

  CH_IRQ_PROLOGUE();

  spc5xx_serve_txi_interrupt(&SD1);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   LINFlex-0 ERR interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(SPC5_LINFLEX0_ERR_HANDLER) {

  CH_IRQ_PROLOGUE();

  spc5xx_serve_err_interrupt(&SD1);

  CH_IRQ_EPILOGUE();
}
#endif

#if SPC5_SERIAL_USE_LINFLEX1 || defined(__DOXYGEN__)
/**
 * @brief   LINFlex-1 RXI interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(SPC5_LINFLEX1_RXI_HANDLER) {

  CH_IRQ_PROLOGUE();

  spc5xx_serve_rxi_interrupt(&SD2);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   LINFlex-1 TXI interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(SPC5_LINFLEX1_TXI_HANDLER) {

  CH_IRQ_PROLOGUE();

  spc5xx_serve_txi_interrupt(&SD2);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   LINFlex-1 ERR interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(SPC5_LINFLEX1_ERR_HANDLER) {

  CH_IRQ_PROLOGUE();

  spc5xx_serve_err_interrupt(&SD2);

  CH_IRQ_EPILOGUE();
}
#endif

/*===========================================================================*/
/* Driver exported functions.                                                */
/*===========================================================================*/

/**
 * @brief   Low level serial driver initialization.
 *
 * @notapi
 */
void sd_lld_init(void) {

#if SPC5_SERIAL_USE_LINFLEX0
  sdObjectInit(&SD1, NULL, notify1);
  SD1.linflexp = &LINFLEX_0;
  INTC.PSR[SPC5_LINFLEX0_RXI_NUMBER].R = SPC5_SERIAL_LINFLEX0_PRIORITY;
  INTC.PSR[SPC5_LINFLEX0_TXI_NUMBER].R = SPC5_SERIAL_LINFLEX0_PRIORITY;
  INTC.PSR[SPC5_LINFLEX0_ERR_NUMBER].R = SPC5_SERIAL_LINFLEX0_PRIORITY;
#endif

#if SPC5_SERIAL_USE_LINFLEX1
  sdObjectInit(&SD2, NULL, notify2);
  SD2.linflexp = &LINFLEX_1;
  INTC.PSR[SPC5_LINFLEX1_RXI_NUMBER].R = SPC5_SERIAL_LINFLEX1_PRIORITY;
  INTC.PSR[SPC5_LINFLEX1_TXI_NUMBER].R = SPC5_SERIAL_LINFLEX1_PRIORITY;
  INTC.PSR[SPC5_LINFLEX1_ERR_NUMBER].R = SPC5_SERIAL_LINFLEX1_PRIORITY;
#endif
}

/**
 * @brief   Low level serial driver configuration and (re)start.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 * @param[in] config    the architecture-dependent serial driver configuration.
 *                      If this parameter is set to @p NULL then a default
 *                      configuration is used.
 *
 * @notapi
 */
void sd_lld_start(SerialDriver *sdp, const SerialConfig *config) {

  if (config == NULL)
    config = &default_config;

  if (sdp->state == SD_STOP) {
#if SPC5_SERIAL_USE_LINFLEX0
    if (&SD1 == sdp) {
      halSPCSetPeripheralClockMode(SPC5_LINFLEX0_PCTL,
                                   SPC5_SERIAL_LINFLEX0_START_PCTL);
    }
#endif
#if SPC5_SERIAL_USE_LINFLEX1
    if (&SD2 == sdp) {
      halSPCSetPeripheralClockMode(SPC5_LINFLEX1_PCTL,
                                   SPC5_SERIAL_LINFLEX1_START_PCTL);
    }
#endif
  }
  spc5_linflex_init(sdp, config);
}

/**
 * @brief   Low level serial driver stop.
 *
 * @param[in] sdp       pointer to a @p SerialDriver object
 *
 * @notapi
 */
void sd_lld_stop(SerialDriver *sdp) {

  if (sdp->state == SD_READY) {
    spc5_linflex_deinit(sdp->linflexp);

#if SPC5_SERIAL_USE_LINFLEX0
    if (&SD1 == sdp) {
      halSPCSetPeripheralClockMode(SPC5_LINFLEX0_PCTL,
                                   SPC5_SERIAL_LINFLEX0_STOP_PCTL);
      return;
    }
#endif
#if SPC5_SERIAL_USE_LINFLEX1
    if (&SD2 == sdp) {
      halSPCSetPeripheralClockMode(SPC5_LINFLEX1_PCTL,
                                   SPC5_SERIAL_LINFLEX1_STOP_PCTL);
      return;
    }
#endif
  }
}

#endif /* HAL_USE_SERIAL */

/** @} */