[KINETIS] K20x SPI converted to use DMA.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@7300 35acf78f-673a-0410-8e92-d51de3d6d3f4

2 files changed, 137 insertions, 129 deletions

diff --git a/os/hal/ports/KINETIS/K20x/spi_lld.c b/os/hal/ports/KINETIS/K20x/spi_lld.c
index 4288d747d..b06dceb15 100644
--- a/os/hal/ports/KINETIS/K20x/spi_lld.c
+++ b/os/hal/ports/KINETIS/K20x/spi_lld.c
@@ -30,6 +30,33 @@
 /* Driver local definitions.                                                 */

 /*===========================================================================*/

 

+#if !defined(KINETIS_SPI_USE_SPI0)

+#define KINETIS_SPI_USE_SPI0                TRUE

+#endif

+

+#if !defined(KINETIS_SPI0_RX_DMA_IRQ_PRIORITY)

+#define KINETIS_SPI0_RX_DMA_IRQ_PRIORITY    8

+#endif

+

+#if !defined(KINETIS_SPI0_RX_DMAMUX_CHANNEL)

+#define KINETIS_SPI0_RX_DMAMUX_CHANNEL      0

+#endif

+

+#if !defined(KINETIS_SPI0_RX_DMA_CHANNEL)

+#define KINETIS_SPI0_RX_DMA_CHANNEL         0

+#endif

+

+#if !defined(KINETIS_SPI0_TX_DMAMUX_CHANNEL)

+#define KINETIS_SPI0_TX_DMAMUX_CHANNEL      1

+#endif

+

+#if !defined(KINETIS_SPI0_TX_DMA_CHANNEL)

+#define KINETIS_SPI0_TX_DMA_CHANNEL         1

+#endif

+

+#define DMAMUX_SPI_RX_SOURCE    16

+#define DMAMUX_SPI_TX_SOURCE    17

+

 /*===========================================================================*/

 /* Driver exported variables.                                                */

 /*===========================================================================*/

@@ -47,40 +74,60 @@ SPIDriver SPID1;
 /* Driver local functions.                                                   */

 /*===========================================================================*/

 

+volatile uint8_t dmaDummy;

+

 static void spi_start_xfer(SPIDriver *spip, bool polling)

 {

   /*

    * Enable the DSPI peripheral in master mode.

-   * On receive overflow, new data will overwrite old data.

-   * Set slave selects to be active low.

    * Clear the TX and RX FIFOs.

    * */

-  spip->spi->MCR = SPIx_MCR_MSTR |

-      SPIx_MCR_ROOE |

-      SPIx_MCR_PCSIS(KINETIS_SPI_PCS_ALL) |

-      SPIx_MCR_CLR_TXF | SPIx_MCR_CLR_RXF;

+  spip->spi->MCR = SPIx_MCR_MSTR | SPIx_MCR_CLR_TXF | SPIx_MCR_CLR_RXF;

 

-  /* If we are not polling then enable interrupts */

+  /* If we are not polling then enable DMA */

   if (!polling) {

 

-    /* Enable transmit fill, receive and end of queue interrupts */

-    spip->spi->RSER = SPIx_RSER_TFFF_RE | SPIx_RSER_RFDF_RE |

-        SPIx_RSER_EOQF_RE;

+    /* Enable receive dma and transmit dma */

+    spip->spi->RSER = SPIx_RSER_RFDF_DIRS | SPIx_RSER_RFDF_RE |

+        SPIx_RSER_TFFF_RE | SPIx_RSER_TFFF_DIRS;

+

+    /* Use dmaDummy as the source/destination when a buffer is not provided */

+    dmaDummy = 0;

+

+    /* Configure RX DMA */

+    if (spip->rxbuf) {

+      DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].DADDR = (uint32_t)spip->rxbuf;

+      DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].DOFF = spip->word_size;

+    } else {

+      DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].DADDR = (uint32_t)&dmaDummy;

+      DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].DOFF = 0;

+    }

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].BITER_ELINKNO = spip->count;

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].CITER_ELINKNO = spip->count;

+

+    /* Enable Request Register (ERQ) for RX by writing 0 to SERQ */

+    DMA->SERQ = KINETIS_SPI0_RX_DMA_CHANNEL;

+

+    /* Configure TX DMA */

+    if (spip->txbuf) {

+      DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].SADDR =  (uint32_t)spip->txbuf;

+      DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].SOFF = spip->word_size;

+    } else {

+      DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].SADDR =  (uint32_t)&dmaDummy;

+      DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].SOFF = 0;

+    }

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].BITER_ELINKNO = spip->count;

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].CITER_ELINKNO = spip->count;

 

+    /* Enable Request Register (ERQ) for TX by writing 1 to SERQ */

+    DMA->SERQ = KINETIS_SPI0_TX_DMA_CHANNEL;

   }

 }

 

 static void spi_stop_xfer(SPIDriver *spip)

 {

   /* Halt the DSPI peripheral */

-  spip->spi->MCR = SPIx_MCR_MSTR |

-      SPIx_MCR_ROOE |

-      SPIx_MCR_PCSIS(KINETIS_SPI_PCS_ALL) |

-      SPIx_MCR_CLR_TXF | SPIx_MCR_CLR_RXF |

-      SPIx_MCR_HALT;

-

-  /* Clear all interrupt enables */

-  spip->spi->RSER = 0;

+  spip->spi->MCR = SPIx_MCR_MSTR | SPIx_MCR_HALT;

 

   /* Clear all the flags which are currently set. */

   spip->spi->SR |= spip->spi->SR;

@@ -90,54 +137,15 @@ static void spi_stop_xfer(SPIDriver *spip)
 /* Driver interrupt handlers.                                                */

 /*===========================================================================*/

 

-OSAL_IRQ_HANDLER(Vector70) {

+OSAL_IRQ_HANDLER(Vector40) {

   OSAL_IRQ_PROLOGUE();

 

-  SPIDriver *spip = &SPID1;

-  uint32_t sr = spip->spi->SR;

-

-  /* Handle Receive FIFO Drain interrupt */

-  if (sr & SPIx_SR_RFDF) {

-

-    /* Pop the data out of the fifo */

-    uint8_t data = spip->spi->POPR;

-

-    /* If we have an rxbuf and it has space then store the data */

-    if (spip->rxbuf && spip->rxidx < spip->nbytes) {

-      spip->rxbuf[spip->rxidx++] = data;

-    }

-

-    /* Clear the Receive FIFO Drain Flag */

-    spip->spi->SR = SPIx_SR_RFDF;

-  }

-

-  /* Handle End of Queue interrupt */

-  if (sr & SPIx_SR_EOQF) {

-

-    spip->spi->SR = SPIx_SR_EOQF;

-

-    spi_stop_xfer(spip);

-

-    _spi_isr_code(spip);

-  }

+  /* Clear bit 0 in Interrupt Request Register (INT) by writing 0 to CINT */

+  DMA->CINT = KINETIS_SPI0_RX_DMA_CHANNEL;

 

-  /* Handle Transmit FIFO Fill interrupt */

-  if (sr & SPIx_SR_TFFF) {

+  spi_stop_xfer(&SPID1);

 

-    /* The data to send is either the next tx byte or a filler byte */

-    uint8_t data = spip->txbuf ? spip->txbuf[spip->txidx] : 0x00;

-

-    /* Calculate the number of bytes remaining and increment the index */

-    size_t n = spip->nbytes - spip->txidx++;

-

-    /* Push the data into the FIFO, CONT if more bytes, EOQ if last byte */

-    spip->spi->PUSHR = (n > 1 ? SPIx_PUSHR_CONT : SPIx_PUSHR_EOQ) |

-        SPIx_PUSHR_PCS(spip->config->pcs) |

-        SPIx_PUSHR_TXDATA(data);

-

-    /* Clear the Transmit FIFO Fill Flag */

-    spip->spi->SR = SPIx_SR_TFFF;

-  }

+  _spi_isr_code(&SPID1);

 

   OSAL_IRQ_EPILOGUE();

 }

@@ -152,13 +160,9 @@ OSAL_IRQ_HANDLER(Vector70) {
  * @notapi

  */

 void spi_lld_init(void) {

-

-  nvicEnableVector(SPI0_IRQn, KINETIS_SPI_SPI0_IRQ_PRIORITY);

-

 #if KINETIS_SPI_USE_SPI0

   spiObjectInit(&SPID1);

 #endif

-

 }

 

 /**

@@ -186,13 +190,56 @@ void spi_lld_start(SPIDriver *spip) {
       } else {

         spip->spi->CTAR[0] = KINETIS_SPI_TAR0_DEFAULT;

       }

-

-      spip->spi->CTAR[1] = KINETIS_SPI_TAR1_DEFAULT;

     }

 #endif

-  }

 

-  /* SPI setup and enable.*/

+    nvicEnableVector(DMA0_IRQn, KINETIS_SPI0_RX_DMA_IRQ_PRIORITY);

+

+    SIM->SCGC6 |= SIM_SCGC6_DMAMUX;

+    SIM->SCGC7 |= SIM_SCGC7_DMA;

+

+    /* Clear DMA error flags */

+    DMA->ERR = 0x0F;

+

+    /* Rx, select SPI Rx FIFO */

+    DMAMUX->CHCFG[KINETIS_SPI0_RX_DMAMUX_CHANNEL] = DMAMUX_CHCFGn_ENBL |

+        DMAMUX_CHCFGn_SOURCE(DMAMUX_SPI_RX_SOURCE);

+

+    /* Tx, select SPI Tx FIFO */

+    DMAMUX->CHCFG[KINETIS_SPI0_TX_DMAMUX_CHANNEL] = DMAMUX_CHCFGn_ENBL |

+        DMAMUX_CHCFGn_SOURCE(DMAMUX_SPI_TX_SOURCE);

+

+    /* Extract the frame size from the TAR */

+    uint16_t frame_size = ((spip->spi->CTAR[0] >> SPIx_CTARn_FMSZ_SHIFT) &

+        SPIx_CTARn_FMSZ_MASK) + 1;

+

+    /* DMA transfer size is 16 bits for a frame size > 8 bits */

+    uint16_t dma_size = frame_size > 8 ? 1 : 0;

+

+    /* DMA word size is 2 for a 16 bit frame size */

+    spip->word_size = frame_size > 8 ? 2 : 1;

+

+    /* configure DMA RX fixed values */

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].SADDR = (uint32_t)&SPI0->POPR;

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].SOFF = 0;

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].SLAST = 0;

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].DLASTSGA = 0;

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].ATTR = DMA_ATTR_SSIZE(dma_size) |

+        DMA_ATTR_DSIZE(dma_size);

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].NBYTES_MLNO = spip->word_size;

+    DMA->TCD[KINETIS_SPI0_RX_DMA_CHANNEL].CSR = DMA_CSR_DREQ_MASK |

+        DMA_CSR_INTMAJOR_MASK;

+

+    /* configure DMA TX fixed values */

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].SLAST = 0;

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].DADDR = (uint32_t)&SPI0->PUSHR;

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].DOFF = 0;

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].DLASTSGA = 0;

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].ATTR = DMA_ATTR_SSIZE(dma_size) |

+        DMA_ATTR_DSIZE(dma_size);

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].NBYTES_MLNO = spip->word_size;

+    DMA->TCD[KINETIS_SPI0_TX_DMA_CHANNEL].CSR = DMA_CSR_DREQ_MASK;

+  }

 }

 

 /**

@@ -207,8 +254,10 @@ void spi_lld_stop(SPIDriver *spip) {
   /* If in ready state then disables the SPI clock.*/

   if (spip->state == SPI_READY) {

 

-    /* Disable the clock for SPI0 */

-    SIM->SCGC6 &= ~SIM_SCGC6_SPI0;

+    nvicDisableVector(DMA0_IRQn);

+

+    SIM->SCGC7 &= ~SIM_SCGC7_DMA;

+    SIM->SCGC6 &= ~SIM_SCGC6_DMAMUX;

 

 #if KINETIS_SPI_USE_SPI0

     if (&SPID1 == spip) {

@@ -216,6 +265,9 @@ void spi_lld_stop(SPIDriver *spip) {
       spip->spi->MCR |= SPIx_MCR_HALT;

     }

 #endif

+

+    /* Disable the clock for SPI0 */

+    SIM->SCGC6 &= ~SIM_SCGC6_SPI0;

   }

 }

 

@@ -228,17 +280,12 @@ void spi_lld_stop(SPIDriver *spip) {
  */

 void spi_lld_select(SPIDriver *spip) {

 

-  /* If we are not using the DSPI managed chip select then assert the SS */

-  if (!spip->config->pcs) {

-    palClearPad(spip->config->ssport, spip->config->sspad);

-  }

+  palClearPad(spip->config->ssport, spip->config->sspad);

 }

 

 /**

  * @brief   Deasserts the slave select signal.

  * @details The previously selected peripheral is unselected.

- *          This has no effect if we are using the KINETIS PCS mode to

- *          manage slave select.

  *

  * @param[in] spip      pointer to the @p SPIDriver object

  *

@@ -246,10 +293,7 @@ void spi_lld_select(SPIDriver *spip) {
  */

 void spi_lld_unselect(SPIDriver *spip) {

 

-  /* If we are not using the DSPI managed chip select then deassert the SS */

-  if (!spip->config->pcs) {

-    palSetPad(spip->config->ssport, spip->config->sspad);

-  }

+  palSetPad(spip->config->ssport, spip->config->sspad);

 }

 

 /**

@@ -265,11 +309,9 @@ void spi_lld_unselect(SPIDriver *spip) {
  */

 void spi_lld_ignore(SPIDriver *spip, size_t n) {

 

-  spip->nbytes = n;

+  spip->count = n;

   spip->rxbuf = NULL;

-  spip->rxidx = 0;

   spip->txbuf = NULL;

-  spip->txidx = 0;

 

   spi_start_xfer(spip, false);

 }

@@ -292,11 +334,9 @@ void spi_lld_ignore(SPIDriver *spip, size_t n) {
 void spi_lld_exchange(SPIDriver *spip, size_t n,

                       const void *txbuf, void *rxbuf) {

 

-  spip->nbytes = n;

+  spip->count = n;

   spip->rxbuf = rxbuf;

-  spip->rxidx = 0;

   spip->txbuf = txbuf;

-  spip->txidx = 0;

 

   spi_start_xfer(spip, false);

 }

@@ -316,11 +356,9 @@ void spi_lld_exchange(SPIDriver *spip, size_t n,
  */

 void spi_lld_send(SPIDriver *spip, size_t n, const void *txbuf) {

 

-  spip->nbytes = n;

+  spip->count = n;

   spip->rxbuf = NULL;

-  spip->rxidx = 0;

   spip->txbuf = (void *)txbuf;

-  spip->txidx = 0;

 

   spi_start_xfer(spip, false);

 }

@@ -340,11 +378,9 @@ void spi_lld_send(SPIDriver *spip, size_t n, const void *txbuf) {
  */

 void spi_lld_receive(SPIDriver *spip, size_t n, void *rxbuf) {

 

-  spip->nbytes = n;

+  spip->count = n;

   spip->rxbuf = rxbuf;

-  spip->rxidx = 0;

   spip->txbuf = NULL;

-  spip->txidx = 0;

 

   spi_start_xfer(spip, false);

 }

@@ -365,7 +401,7 @@ uint16_t spi_lld_polled_exchange(SPIDriver *spip, uint16_t frame) {
 

   spi_start_xfer(spip, true);

 

-  spip->spi->PUSHR = SPIx_PUSHR_PCS(0x10) | SPIx_PUSHR_TXDATA(frame);

+  spip->spi->PUSHR = SPIx_PUSHR_TXDATA(frame);

 

   while ((spip->spi->SR & SPIx_SR_RFDF) == 0)

     ;

diff --git a/os/hal/ports/KINETIS/K20x/spi_lld.h b/os/hal/ports/KINETIS/K20x/spi_lld.h
index 5ab97116e..97588b3a3 100644
--- a/os/hal/ports/KINETIS/K20x/spi_lld.h
+++ b/os/hal/ports/KINETIS/K20x/spi_lld.h
@@ -101,10 +101,6 @@ typedef struct {
   spicallback_t             end_cb;

   /* End of the mandatory fields.*/

   /**

-   * @brief The PCS chip select lines.

-   */

-  uint8_t                   pcs;

-  /**

    * @brief The chip select line port - when not using pcs.

    */

   ioportid_t                ssport;

@@ -151,25 +147,21 @@ struct SPIDriver {
    */

   SPI_TypeDef               *spi;

   /**

-   * @brief   Number of bytes of data to transfer.

+   * @brief   Number of bytes/words of data to transfer.

    */

-  size_t                    nbytes;

+  size_t                    count;

   /**

-   * @brief   Pointer to the buffer with data to send.

+   * @brief   Word size in bytes.

    */

-  const uint8_t             *txbuf;

+  size_t                    word_size;

   /**

-   * @brief   Current index in buffer when sending data.

+   * @brief   Pointer to the buffer with data to send.

    */

-  size_t                    txidx;

+  const uint8_t             *txbuf;

   /**

    * @brief   Pointer to the buffer to put received data.

    */

   uint8_t                   *rxbuf;

-  /**

-   * @brief   Current index in buffer when receiving data.

-   */

-  size_t                    rxidx;

 };

 

 /*===========================================================================*/

@@ -205,26 +197,6 @@ struct SPIDriver {
 #define KINETIS_SPI_TAR0_DEFAULT    KINETIS_SPI_TAR_SYSCLK_DIV_2(8)

 #define KINETIS_SPI_TAR1_DEFAULT    KINETIS_SPI_TAR_SYSCLK_DIV_2(8)

 

-/*

- * A mask of the slave select lines to be managed by KINETIS DSPI.

- *

- * These values are mapped to real ports and pins by selecting

- * PAL_MODE_ALTERNATIVE_2 as the pin mode. Multiple values may

- * be ORed together to select multiple outputs. This can be used with an

- * external multiplexor to increase the number of slave selects.

- *

- * If KINETIS_SPI_PCS_NONE is selected for the configuration pcs field

- * then the configuration ssport and sspad values are used to control the

- * slave select directly and the KINETIS DSPI managed select is not used.

- */

-#define KINETIS_SPI_PCS_NONE        0x00

-#define KINETIS_SPI_PCS0            0x01

-#define KINETIS_SPI_PCS1            0x02

-#define KINETIS_SPI_PCS2            0x04

-#define KINETIS_SPI_PCS3            0x08

-#define KINETIS_SPI_PCS4            0x10

-#define KINETIS_SPI_PCS_ALL         0x1F

-

 /*===========================================================================*/

 /* External declarations.                                                    */

 /*===========================================================================*/