text: /******************************************************************************
  *  Filename:       vims.c
  *  Revised:        2017-06-05 12:13:49 +0200 (Mon, 05 Jun 2017)
  *  Revision:       49096
  *
  *  Description:    Driver for the VIMS.
  *
  *  Copyright (c) 2015 - 2017, Texas Instruments Incorporated
  *  All rights reserved.
  *
  *  Redistribution and use in source and binary forms, with or without
  *  modification, are permitted provided that the following conditions are met:
  *
  *  1) Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *
  *  2) Redistributions in binary form must reproduce the above copyright notice,
  *     this list of conditions and the following disclaimer in the documentation
  *     and/or other materials provided with the distribution.
  *
  *  3) Neither the name of the ORGANIZATION nor the names of its contributors may
  *     be used to endorse or promote products derived from this software without
  *     specific prior written permission.
  *
  *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
  *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  *  POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************/
  
  #include "vims.h"
  
  //*****************************************************************************
  //
  // Handle support for DriverLib in ROM:
  // This section will undo prototype renaming made in the header file
  //
  //*****************************************************************************
  #if !defined(DOXYGEN)
      #undef  VIMSConfigure
      #define VIMSConfigure                   NOROM_VIMSConfigure
      #undef  VIMSModeSet
      #define VIMSModeSet                     NOROM_VIMSModeSet
      #undef  VIMSModeGet
      #define VIMSModeGet                     NOROM_VIMSModeGet
      #undef  VIMSModeSafeSet
      #define VIMSModeSafeSet                 NOROM_VIMSModeSafeSet
  #endif
  
  //*****************************************************************************
  //
  // Configures the VIMS.
  //
  //*****************************************************************************
  void
  VIMSConfigure(uint32_t ui32Base, bool bRoundRobin, bool bPrefetch)
  {
      uint32_t ui32Reg;
  
      // Check the arguments.
      ASSERT(VIMSBaseValid(ui32Base));
  
      ui32Reg = HWREG(ui32Base + VIMS_O_CTL);
      ui32Reg &= ~(VIMS_CTL_PREF_EN | VIMS_CTL_ARB_CFG);
      if(bRoundRobin)
      {
          ui32Reg |= VIMS_CTL_ARB_CFG;
      }
      if(bPrefetch)
      {
          ui32Reg |= VIMS_CTL_PREF_EN;
      }
  
      // Set the Arbitration and prefetch mode.
      HWREG(ui32Base + VIMS_O_CTL) = ui32Reg;
  }
  
  //*****************************************************************************
  //
  // Set the operational mode of the VIMS
  //
  //*****************************************************************************
  void
  VIMSModeSet(uint32_t ui32Base, uint32_t ui32Mode)
  {
      uint32_t ui32Reg;
  
      // Check the arguments.
      ASSERT(VIMSBaseValid(ui32Base));
  
      ASSERT((ui32Mode == VIMS_MODE_DISABLED)   ||
             (ui32Mode == VIMS_MODE_ENABLED)    ||
             (ui32Mode == VIMS_MODE_OFF));
  
      // Set the mode.
      ui32Reg = HWREG(ui32Base + VIMS_O_CTL);
      ui32Reg &= ~VIMS_CTL_MODE_M;
      ui32Reg |= (ui32Mode & VIMS_CTL_MODE_M);
  
      HWREG(ui32Base + VIMS_O_CTL) = ui32Reg;
  }
  
  //*****************************************************************************
  //
  // Get the current operational mode of the VIMS.
  //
  //*****************************************************************************
  uint32_t
  VIMSModeGet(uint32_t ui32Base)
  {
      uint32_t ui32Reg;
  
      // Check the arguments.
      ASSERT(VIMSBaseValid(ui32Base));
  
      ui32Reg = HWREG(ui32Base + VIMS_O_STAT);
      if(ui32Reg & VIMS_STAT_MODE_CHANGING)
      {
          return (VIMS_MODE_CHANGING);
      }
      else
      {
          return (ui32Reg & VIMS_STAT_MODE_M);
      }
  }
  
  //*****************************************************************************
  //
  // Safe setting of new VIMS mode
  // - Function might be blocking
  // - Can be called for any mode change (also if actually not changing mode)
  //
  //*****************************************************************************
  void
  VIMSModeSafeSet( uint32_t ui32Base, uint32_t ui32NewMode, bool blocking )
  {
      uint32_t currentMode;
  
      // Check the arguments.
      ASSERT(VIMSBaseValid(ui32Base));
      ASSERT((ui32NewMode == VIMS_MODE_DISABLED)   ||
             (ui32NewMode == VIMS_MODE_ENABLED)    ||
             (ui32NewMode == VIMS_MODE_OFF));
  
      // Make sure that only the mode bits are set in the input parameter
      // (done just for security since it is critical to the code flow)
      ui32NewMode &= VIMS_CTL_MODE_M;
  
      // Wait for any pending change to complete and get current VIMS mode
      // (This is a blocking point but will typically only be a blocking point
      // only if mode is changed multiple times with blocking=0)
      do {
          currentMode = VIMSModeGet( ui32Base );
      } while ( currentMode == VIMS_MODE_CHANGING );
  
      // First check that it actually is a mode change request
      if ( ui32NewMode != currentMode ) {
          // Set new mode
          VIMSModeSet( ui32Base, ui32NewMode );
  
          // Wait for final mode change to complete - if blocking is requested
          if ( blocking ) {
              while ( HWREGBITW( VIMS_BASE + VIMS_O_STAT, VIMS_STAT_MODE_CHANGING_BITN )) {
                  // Do nothing - wait for change to complete.
              }
          }
      }
  }
  