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/******************************************************************************
*
*     Author: Xilinx, Inc.
*
*
*     This program 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 2 of the License, or (at your
*     option) any later version.
*
*
*     XILINX IS PROVIDING THIS DESIGN, CODE, OR INFORMATION "AS IS" AS A
*     COURTESY TO YOU. BY PROVIDING THIS DESIGN, CODE, OR INFORMATION AS
*     ONE POSSIBLE IMPLEMENTATION OF THIS FEATURE, APPLICATION OR STANDARD,
*     XILINX IS MAKING NO REPRESENTATION THAT THIS IMPLEMENTATION IS FREE
*     FROM ANY CLAIMS OF INFRINGEMENT, AND YOU ARE RESPONSIBLE FOR OBTAINING
*     ANY THIRD PARTY RIGHTS YOU MAY REQUIRE FOR YOUR IMPLEMENTATION.
*     XILINX EXPRESSLY DISCLAIMS ANY WARRANTY WHATSOEVER WITH RESPECT TO
*     THE ADEQUACY OF THE IMPLEMENTATION, INCLUDING BUT NOT LIMITED TO ANY
*     WARRANTIES OR REPRESENTATIONS THAT THIS IMPLEMENTATION IS FREE FROM
*     CLAIMS OF INFRINGEMENT, IMPLIED WARRANTIES OF MERCHANTABILITY AND
*     FITNESS FOR A PARTICULAR PURPOSE.
*
*
*     Xilinx hardware products are not intended for use in life support
*     appliances, devices, or systems. Use in such applications is
*     expressly prohibited.
*
*
*     (c) Copyright 2002-2004 Xilinx Inc.
*     All rights reserved.
*
*
*     You should have received a copy of the GNU General Public License along
*     with this program; if not, write to the Free Software Foundation, Inc.,
*     675 Mass Ave, Cambridge, MA 02139, USA.
*
* FILENAME:
*
* xdma_channel.c
*
* DESCRIPTION:
*
* This file contains the DMA channel component. This component supports
* a distributed DMA design in which each device can have it's own dedicated
* DMA channel, as opposed to a centralized DMA design. This component
* performs processing for DMA on all devices.
*
* See xdma_channel.h for more information about this component.
*
* NOTES:
*
* None.
*
******************************************************************************/

/***************************** Include Files *********************************/

#include "xdma_channel.h"
#include "xbasic_types.h"
#include "xio.h"

/************************** Constant Definitions *****************************/

/**************************** Type Definitions *******************************/

/***************** Macros (Inline Functions) Definitions *********************/

/************************** Function Prototypes ******************************/

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_Initialize
*
* DESCRIPTION:
*
* This function initializes a DMA channel.  This function must be called
* prior to using a DMA channel.  Initialization of a channel includes setting
* up the registers base address, and resetting the channel such that it's in a
* known state.  Interrupts for the channel are disabled when the channel is
* reset.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* BaseAddress contains the base address of the registers for the DMA channel.
*
* RETURN VALUE:
*
* XST_SUCCESS indicating initialization was successful.
*
* NOTES:
*
* None.
*
******************************************************************************/
XStatus
XDmaChannel_Initialize(XDmaChannel * InstancePtr, u32 BaseAddress)
{
	/* assert to verify input arguments, don't assert base address */

	XASSERT_NONVOID(InstancePtr != NULL);

	/* setup the base address of the registers for the DMA channel such
	 * that register accesses can be done
	 */
	InstancePtr->RegBaseAddress = BaseAddress;

	/* initialize the scatter gather list such that it indicates it has not
	 * been created yet and the DMA channel is ready to use (initialized)
	 */
	InstancePtr->GetPtr = NULL;
	InstancePtr->PutPtr = NULL;
	InstancePtr->CommitPtr = NULL;
	InstancePtr->LastPtr = NULL;

	InstancePtr->TotalDescriptorCount = 0;
	InstancePtr->ActiveDescriptorCount = 0;
	InstancePtr->IsReady = XCOMPONENT_IS_READY;

	/* initialize the version of the component
	 */
	XVersion_FromString(&InstancePtr->Version, "1.00a");

	/* reset the DMA channel such that it's in a known state and ready
	 * and indicate the initialization occured with no errors, note that
	 * the is ready variable must be set before this call or reset will assert
	 */
	XDmaChannel_Reset(InstancePtr);

	return XST_SUCCESS;
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_IsReady
*
* DESCRIPTION:
*
* This function determines if a DMA channel component has been successfully
* initialized such that it's ready to use.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* TRUE if the DMA channel component is ready, FALSE otherwise.
*
* NOTES:
*
* None.
*
******************************************************************************/
u32
XDmaChannel_IsReady(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments used by the base component */

	XASSERT_NONVOID(InstancePtr != NULL);

	return InstancePtr->IsReady == XCOMPONENT_IS_READY;
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_GetVersion
*
* DESCRIPTION:
*
* This function gets the software version for the specified DMA channel
* component.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* A pointer to the software version of the specified DMA channel.
*
* NOTES:
*
* None.
*
******************************************************************************/
XVersion *
XDmaChannel_GetVersion(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments */

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* return a pointer to the version of the DMA channel */

	return &InstancePtr->Version;
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_SelfTest
*
* DESCRIPTION:
*
* This function performs a self test on the specified DMA channel.  This self
* test is destructive as the DMA channel is reset and a register default is
* verified.
*
* ARGUMENTS:
*
* InstancePtr is a pointer to the DMA channel to be operated on.
*
* RETURN VALUE:
*
* XST_SUCCESS is returned if the self test is successful, or one of the
* following errors.
*
*	XST_DMA_RESET_REGISTER_ERROR 		Indicates the control register value
*										after a reset was not correct
*
* NOTES:
*
* This test does not performs a DMA transfer to test the channel because the
* DMA hardware will not currently allow a non-local memory transfer to non-local
* memory (memory copy), but only allows a non-local memory to or from the device
* memory (typically a FIFO).
*
******************************************************************************/

#define XDC_CONTROL_REG_RESET_MASK  0x98000000UL	/* control reg reset value */

XStatus
XDmaChannel_SelfTest(XDmaChannel * InstancePtr)
{
	u32 ControlReg;

	/* assert to verify input arguments */

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* reset the DMA channel such that it's in a known state before the test
	 * it resets to no interrupts enabled, the desired state for the test
	 */
	XDmaChannel_Reset(InstancePtr);

	/* this should be the first test to help prevent a lock up with the polling
	 * loop that occurs later in the test, check the reset value of the DMA
	 * control register to make sure it's correct, return with an error if not
	 */
	ControlReg = XDmaChannel_GetControl(InstancePtr);
	if (ControlReg != XDC_CONTROL_REG_RESET_MASK) {
		return XST_DMA_RESET_REGISTER_ERROR;
	}

	return XST_SUCCESS;
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_Reset
*
* DESCRIPTION:
*
* This function resets the DMA channel. This is a destructive operation such
* that it should not be done while a channel is being used.  If the DMA channel
* is transferring data into other blocks, such as a FIFO, it may be necessary
* to reset other blocks.  This function does not modify the contents of a
* scatter gather list for a DMA channel such that the user is responsible for
* getting buffer descriptors from the list if necessary.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* None.
*
* NOTES:
*
* None.
*
******************************************************************************/
void
XDmaChannel_Reset(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments */

	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* reset the DMA channel such that it's in a known state, the reset
	 * register is self clearing such that it only has to be set
	 */
	XIo_Out32(InstancePtr->RegBaseAddress + XDC_RST_REG_OFFSET,
		  XDC_RESET_MASK);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_GetControl
*
* DESCRIPTION:
*
* This function gets the control register contents of the DMA channel.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* The control register contents of the DMA channel. One or more of the
* following values may be contained the register.  Each of the values are
* unique bit masks.
*
*	XDC_DMACR_SOURCE_INCR_MASK	Increment the source address
*	XDC_DMACR_DEST_INCR_MASK	Increment the destination address
*	XDC_DMACR_SOURCE_LOCAL_MASK Local source address
*	XDC_DMACR_DEST_LOCAL_MASK	Local destination address
*	XDC_DMACR_SG_ENABLE_MASK	Scatter gather enable
*	XDC_DMACR_GEN_BD_INTR_MASK	Individual buffer descriptor interrupt
*	XDC_DMACR_LAST_BD_MASK		Last buffer descriptor in a packet
*
* NOTES:
*
* None.
*
******************************************************************************/
u32
XDmaChannel_GetControl(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments */

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* return the contents of the DMA control register */

	return XIo_In32(InstancePtr->RegBaseAddress + XDC_DMAC_REG_OFFSET);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_SetControl
*
* DESCRIPTION:
*
* This function sets the control register of the specified DMA channel.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* Control contains the value to be written to the control register of the DMA
* channel. One or more of the following values may be contained the register.
* Each of the values are unique bit masks such that they may be ORed together
* to enable multiple bits or inverted and ANDed to disable multiple bits.
*
*	XDC_DMACR_SOURCE_INCR_MASK	Increment the source address
*	XDC_DMACR_DEST_INCR_MASK	Increment the destination address
*	XDC_DMACR_SOURCE_LOCAL_MASK Local source address
*	XDC_DMACR_DEST_LOCAL_MASK	Local destination address
*	XDC_DMACR_SG_ENABLE_MASK	Scatter gather enable
*	XDC_DMACR_GEN_BD_INTR_MASK	Individual buffer descriptor interrupt
*	XDC_DMACR_LAST_BD_MASK		Last buffer descriptor in a packet
*
* RETURN VALUE:
*
* None.
*
* NOTES:
*
* None.
*
******************************************************************************/
void
XDmaChannel_SetControl(XDmaChannel * InstancePtr, u32 Control)
{
	/* assert to verify input arguments except the control which can't be
	 * asserted since all values are valid
	 */
	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* set the DMA control register to the specified value */

	XIo_Out32(InstancePtr->RegBaseAddress + XDC_DMAC_REG_OFFSET, Control);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_GetStatus
*
* DESCRIPTION:
*
* This function gets the status register contents of the DMA channel.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* The status register contents of the DMA channel. One or more of the
* following values may be contained the register. Each of the values are
* unique bit masks.
*
*	XDC_DMASR_BUSY_MASK			The DMA channel is busy
*	XDC_DMASR_BUS_ERROR_MASK	A bus error occurred
*	XDC_DMASR_BUS_TIMEOUT_MASK	A bus timeout occurred
*	XDC_DMASR_LAST_BD_MASK		The last buffer descriptor of a packet
*
* NOTES:
*
* None.
*
******************************************************************************/
u32
XDmaChannel_GetStatus(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments */

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* return the contents of the DMA status register */

	return XIo_In32(InstancePtr->RegBaseAddress + XDC_DMAS_REG_OFFSET);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_SetIntrStatus
*
* DESCRIPTION:
*
* This function sets the interrupt status register of the specified DMA channel.
* Setting any bit of the interrupt status register will clear the bit to
* indicate the interrupt processing has been completed. The definitions of each
* bit in the register match the definition of the bits in the interrupt enable
* register.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* Status contains the value to be written to the status register of the DMA
* channel.  One or more of the following values may be contained the register.
* Each of the values are unique bit masks such that they may be ORed together
* to enable multiple bits or inverted and ANDed to disable multiple bits.
*
*	XDC_IXR_DMA_DONE_MASK		The dma operation is done
*	XDC_IXR_DMA_ERROR_MASK	    The dma operation had an error
*	XDC_IXR_PKT_DONE_MASK	    A packet is complete
*	XDC_IXR_PKT_THRESHOLD_MASK 	The packet count threshold reached
*	XDC_IXR_PKT_WAIT_BOUND_MASK The packet wait bound reached
*	XDC_IXR_SG_DISABLE_ACK_MASK The scatter gather disable completed
*	XDC_IXR_BD_MASK				A buffer descriptor is done
*
* RETURN VALUE:
*
* None.
*
* NOTES:
*
* None.
*
******************************************************************************/
void
XDmaChannel_SetIntrStatus(XDmaChannel * InstancePtr, u32 Status)
{
	/* assert to verify input arguments except the status which can't be
	 * asserted since all values are valid
	 */
	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* set the interrupt status register with the specified value such that
	 * all bits which are set in the register are cleared effectively clearing
	 * any active interrupts
	 */
	XIo_Out32(InstancePtr->RegBaseAddress + XDC_IS_REG_OFFSET, Status);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_GetIntrStatus
*
* DESCRIPTION:
*
* This function gets the interrupt status register of the specified DMA channel.
* The interrupt status register indicates which interrupts are active
* for the DMA channel.  If an interrupt is active, the status register must be
* set (written) with the bit set for each interrupt which has been processed
* in order to clear the interrupts.  The definitions of each bit in the register
* match the definition of the bits in the interrupt enable register.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* The interrupt status register contents of the specified DMA channel.
* One or more of the following values may be contained the register.
* Each of the values are unique bit masks.
*
*	XDC_IXR_DMA_DONE_MASK		The dma operation is done
*	XDC_IXR_DMA_ERROR_MASK	    The dma operation had an error
*	XDC_IXR_PKT_DONE_MASK	    A packet is complete
*	XDC_IXR_PKT_THRESHOLD_MASK 	The packet count threshold reached
*	XDC_IXR_PKT_WAIT_BOUND_MASK The packet wait bound reached
*	XDC_IXR_SG_DISABLE_ACK_MASK The scatter gather disable completed
*	XDC_IXR_SG_END_MASK			Current descriptor was the end of the list
*	XDC_IXR_BD_MASK				A buffer descriptor is done
*
* NOTES:
*
* None.
*
******************************************************************************/
u32
XDmaChannel_GetIntrStatus(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments */

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* return the contents of the interrupt status register */

	return XIo_In32(InstancePtr->RegBaseAddress + XDC_IS_REG_OFFSET);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_SetIntrEnable
*
* DESCRIPTION:
*
* This function sets the interrupt enable register of the specified DMA
* channel.  The interrupt enable register contains bits which enable
* individual interrupts for the DMA channel.  The definitions of each bit
* in the register match the definition of the bits in the interrupt status
* register.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* Enable contains the interrupt enable register contents to be written
* in the DMA channel. One or more of the following values may be contained
* the register. Each of the values are unique bit masks such that they may be
* ORed together to enable multiple bits or inverted and ANDed to disable
* multiple bits.
*
*	XDC_IXR_DMA_DONE_MASK		The dma operation is done
*	XDC_IXR_DMA_ERROR_MASK	    The dma operation had an error
*	XDC_IXR_PKT_DONE_MASK	    A packet is complete
*	XDC_IXR_PKT_THRESHOLD_MASK 	The packet count threshold reached
*	XDC_IXR_PKT_WAIT_BOUND_MASK The packet wait bound reached
*	XDC_IXR_SG_DISABLE_ACK_MASK The scatter gather disable completed
*	XDC_IXR_SG_END_MASK			Current descriptor was the end of the list
*	XDC_IXR_BD_MASK				A buffer descriptor is done
*
* RETURN VALUE:
*
* None.
*
* NOTES:
*
* None.
*
******************************************************************************/
void
XDmaChannel_SetIntrEnable(XDmaChannel * InstancePtr, u32 Enable)
{
	/* assert to verify input arguments except the enable which can't be
	 * asserted since all values are valid
	 */
	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* set the interrupt enable register to the specified value */

	XIo_Out32(InstancePtr->RegBaseAddress + XDC_IE_REG_OFFSET, Enable);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_GetIntrEnable
*
* DESCRIPTION:
*
* This function gets the interrupt enable of the DMA channel.  The
* interrupt enable contains flags which enable individual interrupts for the
* DMA channel. The definitions of each bit in the register match the definition
* of the bits in the interrupt status register.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* RETURN VALUE:
*
* The interrupt enable of the DMA channel.  One or more of the following values
* may be contained the register. Each of the values are unique bit masks.
*
*	XDC_IXR_DMA_DONE_MASK		The dma operation is done
*	XDC_IXR_DMA_ERROR_MASK	    The dma operation had an error
*	XDC_IXR_PKT_DONE_MASK	    A packet is complete
*	XDC_IXR_PKT_THRESHOLD_MASK 	The packet count threshold reached
*	XDC_IXR_PKT_WAIT_BOUND_MASK The packet wait bound reached
*	XDC_IXR_SG_DISABLE_ACK_MASK The scatter gather disable completed
*	XDC_IXR_BD_MASK				A buffer descriptor is done
*
* NOTES:
*
* None.
*
******************************************************************************/
u32
XDmaChannel_GetIntrEnable(XDmaChannel * InstancePtr)
{
	/* assert to verify input arguments */

	XASSERT_NONVOID(InstancePtr != NULL);
	XASSERT_NONVOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* return the contents of the interrupt enable register */

	return XIo_In32(InstancePtr->RegBaseAddress + XDC_IE_REG_OFFSET);
}

/******************************************************************************
*
* FUNCTION:
*
* XDmaChannel_Transfer
*
* DESCRIPTION:
*
* This function starts the DMA channel transferring data from a memory source
* to a memory destination. This function only starts the operation and returns
* before the operation may be complete.  If the interrupt is enabled, an
* interrupt will be generated when the operation is complete, otherwise it is
* necessary to poll the channel status to determine when it's complete.  It is
* the responsibility of the caller to determine when the operation is complete
* by handling the generated interrupt or polling the status.  It is also the
* responsibility of the caller to ensure that the DMA channel is not busy with
* another transfer before calling this function.
*
* ARGUMENTS:
*
* InstancePtr contains a pointer to the DMA channel to operate on.
*
* SourcePtr contains a pointer to the source memory where the data is to
* be tranferred from and must be 32 bit aligned.
*
* DestinationPtr contains a pointer to the destination memory where the data
* is to be transferred and must be 32 bit aligned.
*
* ByteCount contains the number of bytes to transfer during the DMA operation.
*
* RETURN VALUE:
*
* None.
*
* NOTES:
*
* The DMA h/w will not currently allow a non-local memory transfer to non-local
* memory (memory copy), but only allows a non-local memory to or from the device
* memory (typically a FIFO).
*
* It is the responsibility of the caller to ensure that the cache is
* flushed and invalidated both before and after the DMA operation completes
* if the memory pointed to is cached. The caller must also ensure that the
* pointers contain a physical address rather than a virtual address
* if address translation is being used.
*
******************************************************************************/
void
XDmaChannel_Transfer(XDmaChannel * InstancePtr,
		     u32 * SourcePtr, u32 * DestinationPtr, u32 ByteCount)
{
	/* assert to verify input arguments and the alignment of any arguments
	 * which have expected alignments
	 */
	XASSERT_VOID(InstancePtr != NULL);
	XASSERT_VOID(SourcePtr != NULL);
	XASSERT_VOID(((u32) SourcePtr & 3) == 0);
	XASSERT_VOID(DestinationPtr != NULL);
	XASSERT_VOID(((u32) DestinationPtr & 3) == 0);
	XASSERT_VOID(ByteCount != 0);
	XASSERT_VOID(InstancePtr->IsReady == XCOMPONENT_IS_READY);

	/* setup the source and destination address registers for the transfer */

	XIo_Out32(InstancePtr->RegBaseAddress + XDC_SA_REG_OFFSET,
		  (u32) SourcePtr);

	XIo_Out32(InstancePtr->RegBaseAddress + XDC_DA_REG_OFFSET,
		  (u32) DestinationPtr);

	/* start the DMA transfer to copy from the source buffer to the
	 * destination buffer by writing the length to the length register
	 */
	XIo_Out32(InstancePtr->RegBaseAddress + XDC_LEN_REG_OFFSET, ByteCount);
}