udma.c

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//*****************************************************************************
//
// udma.c - Driver for the micro-DMA controller.
//
// Copyright (c) 2007-2014 Texas Instruments Incorporated.  All rights reserved.
// Software License Agreement
// 
//   Redistribution and use in source and binary forms, with or without
//   modification, are permitted provided that the following conditions
//   are met:
// 
//   Redistributions of source code must retain the above copyright
//   notice, this list of conditions and the following disclaimer.
// 
//   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.
// 
//   Neither the name of Texas Instruments Incorporated 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
// OWNER 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.
// 
// This is part of revision 2.1.0.12573 of the Tiva Peripheral Driver Library.
//
//*****************************************************************************

//*****************************************************************************
//
//
//*****************************************************************************

#include <stdbool.h>
#include <stdint.h>
#include "inc/hw_sysctl.h"
#include "inc/hw_types.h"
#include "inc/hw_udma.h"
#include "driverlib/debug.h"
#include "driverlib/interrupt.h"
#include "driverlib/udma.h"

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAEnable(void)
{
    //
    // Set the master enable bit in the config register.
    //
    HWREG(UDMA_CFG) = UDMA_CFG_MASTEN;
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMADisable(void)
{
    //
    // Clear the master enable bit in the config register.
    //
    HWREG(UDMA_CFG) = 0;
}

//*****************************************************************************
//
//
//*****************************************************************************
uint32_t
uDMAErrorStatusGet(void)
{
    //
    // Return the uDMA error status.
    //
    return(HWREG(UDMA_ERRCLR));
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAErrorStatusClear(void)
{
    //
    // Clear the uDMA error interrupt.
    //
    HWREG(UDMA_ERRCLR) = 1;
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelEnable(uint32_t ui32ChannelNum)
{
    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);

    //
    // Set the bit for this channel in the enable set register.
    //
    HWREG(UDMA_ENASET) = 1 << (ui32ChannelNum & 0x1f);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelDisable(uint32_t ui32ChannelNum)
{
    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);

    //
    // Set the bit for this channel in the enable clear register.
    //
    HWREG(UDMA_ENACLR) = 1 << (ui32ChannelNum & 0x1f);
}

//*****************************************************************************
//
//
//*****************************************************************************
bool
uDMAChannelIsEnabled(uint32_t ui32ChannelNum)
{
    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);

    //
    // AND the specified channel bit with the enable register and return the
    // result.
    //
    return((HWREG(UDMA_ENASET) & (1 << (ui32ChannelNum & 0x1f))) ? true :
           false);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAControlBaseSet(void *psControlTable)
{
    //
    // Check the arguments.
    //
    ASSERT(((uint32_t)psControlTable & ~0x3FF) ==
           (uint32_t)psControlTable);
    ASSERT((uint32_t)psControlTable >= 0x20000000);

    //
    // Program the base address into the register.
    //
    HWREG(UDMA_CTLBASE) = (uint32_t)psControlTable;
}

//*****************************************************************************
//
//
//*****************************************************************************
void *
uDMAControlBaseGet(void)
{
    //
    // Read the current value of the control base register and return it to
    // the caller.
    //
    return((void *)HWREG(UDMA_CTLBASE));
}

//*****************************************************************************
//
//
//*****************************************************************************
void *
uDMAControlAlternateBaseGet(void)
{
    //
    // Read the current value of the control base register and return it to
    // the caller.
    //
    return((void *)HWREG(UDMA_ALTBASE));
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelRequest(uint32_t ui32ChannelNum)
{
    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);

    //
    // Set the bit for this channel in the software uDMA request register.
    //
    HWREG(UDMA_SWREQ) = 1 << (ui32ChannelNum & 0x1f);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelAttributeEnable(uint32_t ui32ChannelNum, uint32_t ui32Attr)
{
    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);
    ASSERT((ui32Attr & ~(UDMA_ATTR_USEBURST | UDMA_ATTR_ALTSELECT |
                         UDMA_ATTR_HIGH_PRIORITY | UDMA_ATTR_REQMASK)) == 0);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelNum parameter, extract just the channel number
    // from this parameter.
    //
    ui32ChannelNum &= 0x1f;

    //
    // Set the useburst bit for this channel if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_USEBURST)
    {
        HWREG(UDMA_USEBURSTSET) = 1 << ui32ChannelNum;
    }

    //
    // Set the alternate control select bit for this channel,
    // if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_ALTSELECT)
    {
        HWREG(UDMA_ALTSET) = 1 << ui32ChannelNum;
    }

    //
    // Set the high priority bit for this channel, if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_HIGH_PRIORITY)
    {
        HWREG(UDMA_PRIOSET) = 1 << ui32ChannelNum;
    }

    //
    // Set the request mask bit for this channel, if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_REQMASK)
    {
        HWREG(UDMA_REQMASKSET) = 1 << ui32ChannelNum;
    }
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelAttributeDisable(uint32_t ui32ChannelNum, uint32_t ui32Attr)
{
    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);
    ASSERT((ui32Attr & ~(UDMA_ATTR_USEBURST | UDMA_ATTR_ALTSELECT |
                         UDMA_ATTR_HIGH_PRIORITY | UDMA_ATTR_REQMASK)) == 0);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelNum parameter, extract just the channel number
    // from this parameter.
    //
    ui32ChannelNum &= 0x1f;

    //
    // Clear the useburst bit for this channel if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_USEBURST)
    {
        HWREG(UDMA_USEBURSTCLR) = 1 << ui32ChannelNum;
    }

    //
    // Clear the alternate control select bit for this channel, if set in
    // ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_ALTSELECT)
    {
        HWREG(UDMA_ALTCLR) = 1 << ui32ChannelNum;
    }

    //
    // Clear the high priority bit for this channel, if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_HIGH_PRIORITY)
    {
        HWREG(UDMA_PRIOCLR) = 1 << ui32ChannelNum;
    }

    //
    // Clear the request mask bit for this channel, if set in ui32Config.
    //
    if(ui32Attr & UDMA_ATTR_REQMASK)
    {
        HWREG(UDMA_REQMASKCLR) = 1 << ui32ChannelNum;
    }
}

//*****************************************************************************
//
//
//*****************************************************************************
uint32_t
uDMAChannelAttributeGet(uint32_t ui32ChannelNum)
{
    uint32_t ui32Attr = 0;

    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelNum parameter, extract just the channel number
    // from this parameter.
    //
    ui32ChannelNum &= 0x1f;

    //
    // Check to see if useburst bit is set for this channel.
    //
    if(HWREG(UDMA_USEBURSTSET) & (1 << ui32ChannelNum))
    {
        ui32Attr |= UDMA_ATTR_USEBURST;
    }

    //
    // Check to see if the alternate control bit is set for this channel.
    //
    if(HWREG(UDMA_ALTSET) & (1 << ui32ChannelNum))
    {
        ui32Attr |= UDMA_ATTR_ALTSELECT;
    }

    //
    // Check to see if the high priority bit is set for this channel.
    //
    if(HWREG(UDMA_PRIOSET) & (1 << ui32ChannelNum))
    {
        ui32Attr |= UDMA_ATTR_HIGH_PRIORITY;
    }

    //
    // Check to see if the request mask bit is set for this channel.
    //
    if(HWREG(UDMA_REQMASKSET) & (1 << ui32ChannelNum))
    {
        ui32Attr |= UDMA_ATTR_REQMASK;
    }

    //
    // Return the configuration flags.
    //
    return(ui32Attr);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelControlSet(uint32_t ui32ChannelStructIndex, uint32_t ui32Control)
{
    tDMAControlTable *psCtl;

    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelStructIndex & 0xffff) < 64);
    ASSERT(HWREG(UDMA_CTLBASE) != 0);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelStructIndex parameter, extract just the channel
    // index from this parameter.
    //
    ui32ChannelStructIndex &= 0x3f;

    //
    // Get the base address of the control table.
    //
    psCtl = (tDMAControlTable *)HWREG(UDMA_CTLBASE);

    //
    // Get the current control word value and mask off the fields to be
    // changed, then OR in the new settings.
    //
    psCtl[ui32ChannelStructIndex].ui32Control =
        ((psCtl[ui32ChannelStructIndex].ui32Control &
          ~(UDMA_CHCTL_DSTINC_M |
            UDMA_CHCTL_DSTSIZE_M |
            UDMA_CHCTL_SRCINC_M |
            UDMA_CHCTL_SRCSIZE_M |
            UDMA_CHCTL_ARBSIZE_M |
            UDMA_CHCTL_NXTUSEBURST)) |
         ui32Control);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelTransferSet(uint32_t ui32ChannelStructIndex, uint32_t ui32Mode,
                       void *pvSrcAddr, void *pvDstAddr,
                       uint32_t ui32TransferSize)
{
    tDMAControlTable *psControlTable;
    uint32_t ui32Control;
    uint32_t ui32Inc;
    uint32_t ui32BufferBytes;

    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelStructIndex & 0xffff) < 64);
    ASSERT(HWREG(UDMA_CTLBASE) != 0);
    ASSERT(ui32Mode <= UDMA_MODE_PER_SCATTER_GATHER);
    ASSERT((uint32_t)pvSrcAddr >= 0x20000000);
    ASSERT((uint32_t)pvDstAddr >= 0x20000000);
    ASSERT((ui32TransferSize != 0) && (ui32TransferSize <= 1024));

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelStructIndex parameter, extract just the channel
    // index from this parameter.
    //
    ui32ChannelStructIndex &= 0x3f;

    //
    // Get the base address of the control table.
    //
    psControlTable = (tDMAControlTable *)HWREG(UDMA_CTLBASE);

    //
    // Get the current control word value and mask off the mode and size
    // fields.
    //
    ui32Control = (psControlTable[ui32ChannelStructIndex].ui32Control &
                   ~(UDMA_CHCTL_XFERSIZE_M | UDMA_CHCTL_XFERMODE_M));

    //
    // Adjust the mode if the alt control structure is selected.
    //
    if(ui32ChannelStructIndex & UDMA_ALT_SELECT)
    {
        if((ui32Mode == UDMA_MODE_MEM_SCATTER_GATHER) ||
           (ui32Mode == UDMA_MODE_PER_SCATTER_GATHER))
        {
            ui32Mode |= UDMA_MODE_ALT_SELECT;
        }
    }

    //
    // Set the transfer size and mode in the control word (but don't write the
    // control word yet as it could kick off a transfer).
    //
    ui32Control |= ui32Mode | ((ui32TransferSize - 1) << 4);

    //
    // Get the address increment value for the source, from the control word.
    //
    ui32Inc = (ui32Control & UDMA_CHCTL_SRCINC_M);

    //
    // Compute the ending source address of the transfer.  If the source
    // increment is set to none, then the ending address is the same as the
    // beginning.
    //
    if(ui32Inc != UDMA_SRC_INC_NONE)
    {
        ui32Inc = ui32Inc >> 26;
        ui32BufferBytes = ui32TransferSize << ui32Inc;
        pvSrcAddr = (void *)((uint32_t)pvSrcAddr + ui32BufferBytes - 1);
    }

    //
    // Load the source ending address into the control block.
    //
    psControlTable[ui32ChannelStructIndex].pvSrcEndAddr = pvSrcAddr;

    //
    // Get the address increment value for the destination, from the control
    // word.
    //
    ui32Inc = ui32Control & UDMA_CHCTL_DSTINC_M;

    //
    // Compute the ending destination address of the transfer.  If the
    // destination increment is set to none, then the ending address is the
    // same as the beginning.
    //
    if(ui32Inc != UDMA_DST_INC_NONE)
    {
        //
        // There is a special case if this is setting up a scatter-gather
        // transfer.  The destination pointer must point to the end of
        // the alternate structure for this channel instead of calculating
        // the end of the buffer in the normal way.
        //
        if((ui32Mode == UDMA_MODE_MEM_SCATTER_GATHER) ||
           (ui32Mode == UDMA_MODE_PER_SCATTER_GATHER))
        {
            pvDstAddr =
                (void *)&psControlTable[ui32ChannelStructIndex |
                                        UDMA_ALT_SELECT].ui32Spare;
        }
        //
        // Not a scatter-gather transfer, calculate end pointer normally.
        //
        else
        {
            ui32Inc = ui32Inc >> 30;
            ui32BufferBytes = ui32TransferSize << ui32Inc;
            pvDstAddr = (void *)((uint32_t)pvDstAddr + ui32BufferBytes - 1);
        }
    }

    //
    // Load the destination ending address into the control block.
    //
    psControlTable[ui32ChannelStructIndex].pvDstEndAddr = pvDstAddr;

    //
    // Write the new control word value.
    //
    psControlTable[ui32ChannelStructIndex].ui32Control = ui32Control;
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelScatterGatherSet(uint32_t ui32ChannelNum, uint32_t ui32TaskCount,
                            void *pvTaskList, uint32_t ui32IsPeriphSG)
{
    tDMAControlTable *psControlTable;
    tDMAControlTable *psTaskTable;

    //
    // Check the parameters
    //
    ASSERT((ui32ChannelNum & 0xffff) < 32);
    ASSERT(HWREG(UDMA_CTLBASE) != 0);
    ASSERT(pvTaskList != 0);
    ASSERT(ui32TaskCount <= 1024);
    ASSERT(ui32TaskCount != 0);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelNum parameter, extract just the channel number
    // from this parameter.
    //
    ui32ChannelNum &= 0x1f;

    //
    // Get the base address of the control table.
    //
    psControlTable = (tDMAControlTable *)HWREG(UDMA_CTLBASE);

    //
    // Get a handy pointer to the task list
    //
    psTaskTable = (tDMAControlTable *)pvTaskList;

    //
    // Compute the ending address for the source pointer.  This address is the
    // last element of the last task in the task table
    //
    psControlTable[ui32ChannelNum].pvSrcEndAddr =
        &psTaskTable[ui32TaskCount - 1].ui32Spare;

    //
    // Compute the ending address for the destination pointer.  This address
    // is the end of the alternate structure for this channel.
    //
    psControlTable[ui32ChannelNum].pvDstEndAddr =
        &psControlTable[ui32ChannelNum | UDMA_ALT_SELECT].ui32Spare;

    //
    // Compute the control word.  Most configurable items are fixed for
    // scatter-gather.  Item and increment sizes are all 32-bit and arb
    // size must be 4.  The count is the number of items in the task list
    // times 4 (4 words per task).
    //
    psControlTable[ui32ChannelNum].ui32Control =
        (UDMA_CHCTL_DSTINC_32 | UDMA_CHCTL_DSTSIZE_32 |
         UDMA_CHCTL_SRCINC_32 | UDMA_CHCTL_SRCSIZE_32 |
         UDMA_CHCTL_ARBSIZE_4 |
         (((ui32TaskCount * 4) - 1) << UDMA_CHCTL_XFERSIZE_S) |
         (ui32IsPeriphSG ? UDMA_CHCTL_XFERMODE_PER_SG :
          UDMA_CHCTL_XFERMODE_MEM_SG));

    //
    // Scatter-gather operations can leave the alt bit set.  So if doing
    // back to back scatter-gather transfers, the second attempt may not
    // work correctly because the alt bit is set.  Therefore, clear the
    // alt bit here to ensure that it is always cleared before a new SG
    // transfer is started.
    //
    HWREG(UDMA_ALTCLR) = 1 << ui32ChannelNum;
}

//*****************************************************************************
//
//
//*****************************************************************************
uint32_t
uDMAChannelSizeGet(uint32_t ui32ChannelStructIndex)
{
    tDMAControlTable *psControlTable;
    uint32_t ui32Control;

    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelStructIndex & 0xffff) < 64);
    ASSERT(HWREG(UDMA_CTLBASE) != 0);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelStructIndex parameter, extract just the channel
    // index from this parameter.
    //
    ui32ChannelStructIndex &= 0x3f;

    //
    // Get the base address of the control table.
    //
    psControlTable = (tDMAControlTable *)HWREG(UDMA_CTLBASE);

    //
    // Get the current control word value and mask off all but the size field
    // and the mode field.
    //
    ui32Control = (psControlTable[ui32ChannelStructIndex].ui32Control &
                   (UDMA_CHCTL_XFERSIZE_M | UDMA_CHCTL_XFERMODE_M));

    //
    // If the size field and mode field are 0 then the transfer is finished
    // and there are no more items to transfer
    //
    if(ui32Control == 0)
    {
        return(0);
    }

    //
    // Otherwise, if either the size field or more field is non-zero, then
    // not all the items have been transferred.
    //
    else
    {
        //
        // Shift the size field and add one, then return to user.
        //
        return((ui32Control >> 4) + 1);
    }
}

//*****************************************************************************
//
//
//*****************************************************************************
uint32_t
uDMAChannelModeGet(uint32_t ui32ChannelStructIndex)
{
    tDMAControlTable *psControlTable;
    uint32_t ui32Control;

    //
    // Check the arguments.
    //
    ASSERT((ui32ChannelStructIndex & 0xffff) < 64);
    ASSERT(HWREG(UDMA_CTLBASE) != 0);

    //
    // In case a channel selector macro (like UDMA_CH0_USB0EP1RX) was
    // passed as the ui32ChannelStructIndex parameter, extract just the channel
    // index from this parameter.
    //
    ui32ChannelStructIndex &= 0x3f;

    //
    // Get the base address of the control table.
    //
    psControlTable = (tDMAControlTable *)HWREG(UDMA_CTLBASE);

    //
    // Get the current control word value and mask off all but the mode field.
    //
    ui32Control = (psControlTable[ui32ChannelStructIndex].ui32Control &
                   UDMA_CHCTL_XFERMODE_M);

    //
    // Check if scatter/gather mode, and if so, mask off the alt bit.
    //
    if(((ui32Control & ~UDMA_MODE_ALT_SELECT) ==
        UDMA_MODE_MEM_SCATTER_GATHER) ||
       ((ui32Control & ~UDMA_MODE_ALT_SELECT) == UDMA_MODE_PER_SCATTER_GATHER))
    {
        ui32Control &= ~UDMA_MODE_ALT_SELECT;
    }

    //
    // Return the mode to the caller.
    //
    return(ui32Control);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAIntRegister(uint32_t ui32IntChannel, void (*pfnHandler)(void))
{
    //
    // Check the arguments.
    //
    ASSERT(pfnHandler);
    ASSERT((ui32IntChannel == UDMA_INT_SW) ||
           (ui32IntChannel == UDMA_INT_ERR));

    //
    // Register the interrupt handler.
    //
    IntRegister(ui32IntChannel, pfnHandler);

    //
    // Enable the memory management fault.
    //
    IntEnable(ui32IntChannel);
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAIntUnregister(uint32_t ui32IntChannel)
{
    //
    // Disable the interrupt.
    //
    IntDisable(ui32IntChannel);

    //
    // Unregister the interrupt handler.
    //
    IntUnregister(ui32IntChannel);
}

//*****************************************************************************
//
//
//*****************************************************************************
uint32_t
uDMAIntStatus(void)
{
    //
    // Return the value of the uDMA interrupt status register
    //
    return(HWREG(UDMA_CHIS));
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAIntClear(uint32_t ui32ChanMask)
{
    //
    // Clear the requested bits in the uDMA interrupt status register
    //
    HWREG(UDMA_CHIS) = ui32ChanMask;
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelAssign(uint32_t ui32Mapping)
{
    uint32_t ui32MapReg;
    uint_fast8_t ui8MapShift;
    uint_fast8_t ui8ChannelNum;

    //
    // Check the parameters
    //
    ASSERT((ui32Mapping & 0xffffff00) < 0x00050000);

    //
    // Extract the channel number and map encoding value from the parameter.
    //
    ui8ChannelNum = ui32Mapping & 0xff;
    ui32Mapping = ui32Mapping >> 16;

    //
    // Find the uDMA channel mapping register and shift value to use for this
    // channel
    //
    ui32MapReg = UDMA_CHMAP0 + (uint32_t)((ui8ChannelNum / 8) * 4);
    ui8MapShift = (ui8ChannelNum % 8) * 4;

    //
    // Set the channel map encoding for this channel
    //
    HWREG(ui32MapReg) = (HWREG(ui32MapReg) & ~(0xf << ui8MapShift)) |
                        ui32Mapping << ui8MapShift;
}

//*****************************************************************************
//
// The following functions are deprecated.  Use uDMAChannelAssign() instead
// to accomplish the same end.
//
//*****************************************************************************
#ifndef DEPRECATED
//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelSelectSecondary(uint32_t ui32SecPeriphs)
{
    //
    // Select the secondary peripheral for the specified channels.
    //
    HWREG(UDMA_CHASGN) |= ui32SecPeriphs;
}

//*****************************************************************************
//
//
//*****************************************************************************
void
uDMAChannelSelectDefault(uint32_t ui32DefPeriphs)
{
    //
    // Select the default peripheral for the specified channels.
    //
    HWREG(UDMA_CHASGN) &= ~ui32DefPeriphs;
}
#endif

//*****************************************************************************
//
// Close the Doxygen group.
//
//*****************************************************************************