aboutsummaryrefslogtreecommitdiffstats
path: root/docs/conf.py
Commit message (Expand)AuthorAgeFilesLines
* Delete a bunch of commented out defaults in docs/conf.pyAlex Gaynor2016-02-271-100/+0
* Make the linkcheck builder more resillient against transient network errors.Alex Gaynor2016-02-131-0/+4
* Bump the copyright yearAlex Gaynor2016-01-011-1/+1
* make our docs job nitpicky and fix every broken linkPaul Kehrer2015-02-121-1/+3
* Bump some more yearsAlex Gaynor2015-01-081-1/+1
* Use HTTPS for a number of URLs in the docsAlex Gaynor2014-12-121-1/+1
* Update the license header for every source file, as well as the documentation.Alex Gaynor2014-11-161-12/+3
* Move the cryptography package into a src/ subdirectoryDonald Stufft2014-11-131-1/+1
* A new flake8 is out. Our code is bad again!Alex Gaynor2014-03-261-45/+37
* Added future imports and licenses that are missingAlex Gaynor2014-03-081-0/+16
* Specify the epub theme to fix the epub build on RTD.David Reid2014-01-161-0/+2
* Don't require sphinx spelling to be installed, for readthedocs benefitAlex Gaynor2014-01-161-1/+8
* Try to run the spellchecker on travisAlex Gaynor2014-01-101-0/+1
* Compute the version in the same way as setup.py doesAlex Gaynor2014-01-061-4/+7
* Bump the copyright yearAlex Gaynor2014-01-011-1/+1
* Update documentation again to make it clearer what this is for. Moved to usin...Julian Krause2013-12-121-2/+0
* Improve documentation.Julian Krause2013-12-051-0/+1
* Try to use the sphinx rtd theme locally if it's installedAlex Gaynor2013-11-081-4/+12
* pep8 fixAlex Gaynor2013-11-041-1/+0
* This is now the default theme on RTDAlex Gaynor2013-11-041-3/+0
* Made a sphinx extension which emits the hazardous materials danger admonitionAlex Gaynor2013-10-291-1/+5
* Enable the new read the docs theme, it's pretty.Alex Gaynor2013-10-221-0/+4
* Use the Sphinx doctest builderDonald Stufft2013-08-111-0/+1
* Python 3.2 compatibilityAlex Gaynor2013-08-071-8/+8
* Pep8 corrections to docs/conf.pyAlex Gaynor2013-08-071-25/+28
* Initial commit. Migrates over basic project files, and the OpenSSL bindingsAlex Gaynor2013-08-061-0/+246
>301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348
/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011,2012 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    STM32L1xx/stm32_dma.c
 * @brief   DMA helper driver code.
 *
 * @addtogroup STM32L1xx_DMA
 * @details DMA sharing helper driver. In the STM32 the DMA streams are a
 *          shared resource, this driver allows to allocate and free DMA
 *          streams at runtime in order to allow all the other device
 *          drivers to coordinate the access to the resource.
 * @note    The DMA ISR handlers are all declared into this module because
 *          sharing, the various device drivers can associate a callback to
 *          ISRs when allocating streams.
 * @{
 */

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

/* The following macro is only defined if some driver requiring DMA services
   has been enabled.*/
#if defined(STM32_DMA_REQUIRED) || defined(__DOXYGEN__)

/*===========================================================================*/
/* Driver local definitions.                                                 */
/*===========================================================================*/

/**
 * @brief   Mask of the DMA1 streams in @p dma_streams_mask.
 */
#define STM32_DMA1_STREAMS_MASK     0x0000007F

/**
 * @brief   Mask of the DMA2 streams in @p dma_streams_mask.
 */
#define STM32_DMA2_STREAMS_MASK     0x00000F80

/**
 * @brief   Post-reset value of the stream CCR register.
 */
#define STM32_DMA_CCR_RESET_VALUE   0x00000000

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

/**
 * @brief   DMA streams descriptors.
 * @details This table keeps the association between an unique stream
 *          identifier and the involved physical registers.
 * @note    Don't use this array directly, use the appropriate wrapper macros
 *          instead: @p STM32_DMA1_STREAM1, @p STM32_DMA1_STREAM2 etc.
 */
const stm32_dma_stream_t _stm32_dma_streams[STM32_DMA_STREAMS] = {
  {DMA1_Channel1, &DMA1->IFCR, 0, 0, DMA1_Channel1_IRQn},
  {DMA1_Channel2, &DMA1->IFCR, 4, 1, DMA1_Channel2_IRQn},
  {DMA1_Channel3, &DMA1->IFCR, 8, 2, DMA1_Channel3_IRQn},
  {DMA1_Channel4, &DMA1->IFCR, 12, 3, DMA1_Channel4_IRQn},
  {DMA1_Channel5, &DMA1->IFCR, 16, 4, DMA1_Channel5_IRQn},
  {DMA1_Channel6, &DMA1->IFCR, 20, 5, DMA1_Channel6_IRQn},
  {DMA1_Channel7, &DMA1->IFCR, 24, 6, DMA1_Channel7_IRQn}
};

/*===========================================================================*/
/* Driver local variables and types.                                         */
/*===========================================================================*/

/**
 * @brief   DMA ISR redirector type.
 */
typedef struct {
  stm32_dmaisr_t        dma_func;       /**< @brief DMA callback function.  */
  void                  *dma_param;     /**< @brief DMA callback parameter. */
} dma_isr_redir_t;

/**
 * @brief   Mask of the allocated streams.
 */
static uint32_t dma_streams_mask;

/**
 * @brief   DMA IRQ redirectors.
 */
static dma_isr_redir_t dma_isr_redir[STM32_DMA_STREAMS];

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

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

/**
 * @brief   DMA1 stream 1 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch1_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 0) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 0;
  if (dma_isr_redir[0].dma_func)
    dma_isr_redir[0].dma_func(dma_isr_redir[0].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   DMA1 stream 2 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch2_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 4) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 4;
  if (dma_isr_redir[1].dma_func)
    dma_isr_redir[1].dma_func(dma_isr_redir[1].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   DMA1 stream 3 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch3_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 8) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 8;
  if (dma_isr_redir[2].dma_func)
    dma_isr_redir[2].dma_func(dma_isr_redir[2].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   DMA1 stream 4 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch4_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 12) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 12;
  if (dma_isr_redir[3].dma_func)
    dma_isr_redir[3].dma_func(dma_isr_redir[3].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   DMA1 stream 5 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch5_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 16) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 16;
  if (dma_isr_redir[4].dma_func)
    dma_isr_redir[4].dma_func(dma_isr_redir[4].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   DMA1 stream 6 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch6_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 20) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 20;
  if (dma_isr_redir[5].dma_func)
    dma_isr_redir[5].dma_func(dma_isr_redir[5].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

/**
 * @brief   DMA1 stream 7 shared interrupt handler.
 *
 * @isr
 */
CH_IRQ_HANDLER(DMA1_Ch7_IRQHandler) {
  uint32_t flags;

  CH_IRQ_PROLOGUE();

  flags = (DMA1->ISR >> 24) & STM32_DMA_ISR_MASK;
  DMA1->IFCR = STM32_DMA_ISR_MASK << 24;
  if (dma_isr_redir[6].dma_func)
    dma_isr_redir[6].dma_func(dma_isr_redir[6].dma_param, flags);

  CH_IRQ_EPILOGUE();
}

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

/**
 * @brief   STM32 DMA helper initialization.
 *
 * @init
 */
void dmaInit(void) {
  int i;

  dma_streams_mask = 0;
  for (i = 0; i < STM32_DMA_STREAMS; i++) {
    _stm32_dma_streams[i].channel->CCR = 0;
    dma_isr_redir[i].dma_func = NULL;
  }
  DMA1->IFCR = 0xFFFFFFFF;
}

/**
 * @brief   Allocates a DMA stream.
 * @details The stream is allocated and, if required, the DMA clock enabled.
 *          The function also enables the IRQ vector associated to the stream
 *          and initializes its priority.
 * @pre     The stream must not be already in use or an error is returned.
 * @post    The stream is allocated and the default ISR handler redirected
 *          to the specified function.
 * @post    The stream ISR vector is enabled and its priority configured.
 * @post    The stream must be freed using @p dmaStreamRelease() before it can
 *          be reused with another peripheral.
 * @post    The stream is in its post-reset state.
 * @note    This function can be invoked in both ISR or thread context.
 *
 * @param[in] dmastp    pointer to a stm32_dma_stream_t structure
 * @param[in] priority  IRQ priority mask for the DMA stream
 * @param[in] func      handling function pointer, can be @p NULL
 * @param[in] param     a parameter to be passed to the handling function
 * @return              The operation status.
 * @retval FALSE        no error, stream taken.
 * @retval TRUE         error, stream already taken.
 *
 * @special
 */
bool_t dmaStreamAllocate(const stm32_dma_stream_t *dmastp,
                         uint32_t priority,
                         stm32_dmaisr_t func,
                         void *param) {

  chDbgCheck(dmastp != NULL, "dmaAllocate");

  /* Checks if the stream is already taken.*/
  if ((dma_streams_mask & (1 << dmastp->selfindex)) != 0)
    return TRUE;

  /* Marks the stream as allocated.*/
  dma_isr_redir[dmastp->selfindex].dma_func  = func;
  dma_isr_redir[dmastp->selfindex].dma_param = param;
  dma_streams_mask |= (1 << dmastp->selfindex);

  /* Enabling DMA clocks required by the current streams set.*/
  if ((dma_streams_mask & STM32_DMA1_STREAMS_MASK) != 0)
    rccEnableDMA1(FALSE);

  /* Putting the stream in a safe state.*/
  dmaStreamDisable(dmastp);
  dmastp->channel->CCR = STM32_DMA_CCR_RESET_VALUE;

  /* Enables the associated IRQ vector if a callback is defined.*/
  if (func != NULL)
    nvicEnableVector(dmastp->vector, CORTEX_PRIORITY_MASK(priority));

  return FALSE;
}

/**
 * @brief   Releases a DMA stream.
 * @details The stream is freed and, if required, the DMA clock disabled.
 *          Trying to release a unallocated stream is an illegal operation
 *          and is trapped if assertions are enabled.
 * @pre     The stream must have been allocated using @p dmaStreamAllocate().
 * @post    The stream is again available.
 * @note    This function can be invoked in both ISR or thread context.
 *
 * @param[in] dmastp    pointer to a stm32_dma_stream_t structure
 *
 * @special
 */
void dmaStreamRelease(const stm32_dma_stream_t *dmastp) {

  chDbgCheck(dmastp != NULL, "dmaRelease");

  /* Check if the streams is not taken.*/
  chDbgAssert((dma_streams_mask & (1 << dmastp->selfindex)) != 0,
              "dmaRelease(), #1", "not allocated");

  /* Disables the associated IRQ vector.*/
  nvicDisableVector(dmastp->vector);

  /* Marks the stream as not allocated.*/
  dma_streams_mask &= ~(1 << dmastp->selfindex);

  /* Shutting down clocks that are no more required, if any.*/
  if ((dma_streams_mask & STM32_DMA1_STREAMS_MASK) == 0)
    rccDisableDMA1(FALSE);
}

#endif /* STM32_DMA_REQUIRED */

/** @} */