/**
*
* This function handles the receive timeout interrupt. This interrupt occurs
* whenever a number of bytes have been present in the RX FIFO and the receive
* data line has been idle for at lease 4 or more character times, (the timeout
* is set using XUartPs_SetrecvTimeout() function).
*
* @param InstancePtr is a pointer to the XUartPs instance
*
* @return None.
*
* @note None.
*
*****************************************************************************/
static void ReceiveTimeoutHandler(XUartPs *InstancePtr)
{
u32 Event;
/*
* If there are bytes still to be received in the specified buffer
* go ahead and receive them. Removing bytes from the RX FIFO will
* clear the interrupt.
*/
if (InstancePtr->ReceiveBuffer.RemainingBytes != (u32)0) {
(void)XUartPs_ReceiveBuffer(InstancePtr);
}
/*
* If there are no more bytes to receive then indicate that this is
* not a receive timeout but the end of the buffer reached, a timeout
* normally occurs if # of bytes is not divisible by FIFO threshold,
* don't rely on previous test of remaining bytes since receive
* function updates it
*/
if (InstancePtr->ReceiveBuffer.RemainingBytes != (u32)0) {
Event = XUARTPS_EVENT_RECV_TOUT;
} else {
Event = XUARTPS_EVENT_RECV_DATA;
}
/*
* Call the application handler to indicate that there is a receive
* timeout or data event
*/
InstancePtr->Handler(InstancePtr->CallBackRef, Event,
InstancePtr->ReceiveBuffer.RequestedBytes -
InstancePtr->ReceiveBuffer.RemainingBytes);
}
/**
*
* This function handles the interrupt when data is in RX FIFO.
*
* @param InstancePtr is a pointer to the XUartPs instance
*
* @return None.
*
* @note None.
*
*****************************************************************************/
static void ReceiveDataHandler(XUartPs *InstancePtr)
{
/*
* If there are bytes still to be received in the specified buffer
* go ahead and receive them. Removing bytes from the RX FIFO will
* clear the interrupt.
*/
if (InstancePtr->ReceiveBuffer.RemainingBytes != 0) {
XUartPs_ReceiveBuffer(InstancePtr);
}
/* If the last byte of a message was received then call the application
* handler, this code should not use an else from the previous check of
* the number of bytes to receive because the call to receive the buffer
* updates the bytes ramained
*/
if (InstancePtr->ReceiveBuffer.RemainingBytes == 0) {
InstancePtr->Handler(InstancePtr->CallBackRef,
XUARTPS_EVENT_RECV_DATA,
(InstancePtr->ReceiveBuffer.RequestedBytes -
InstancePtr->ReceiveBuffer.RemainingBytes));
}
}
/*
*
* This function handles interrupts for receive errors which include
* overrun errors, framing errors, parity errors, and the break interrupt.
*
* @param InstancePtr is a pointer to the XUartPs instance.
*
* @return None.
*
* @note None.
*
*****************************************************************************/
static void ReceiveErrorHandler(XUartPs *InstancePtr, u32 IsrStatus)
{
u32 ByteStatusValue, EventData;
u32 Event;
InstancePtr->is_rxbs_error = 0;
if ((InstancePtr->Platform == XPLAT_ZYNQ_ULTRA_MP) &&
(IsrStatus & ((u32)XUARTPS_IXR_PARITY | (u32)XUARTPS_IXR_RBRK
| (u32)XUARTPS_IXR_FRAMING))) {
InstancePtr->is_rxbs_error = 1;
}
/*
* If there are bytes still to be received in the specified buffer
* go ahead and receive them. Removing bytes from the RX FIFO will
* clear the interrupt.
*/
(void)XUartPs_ReceiveBuffer(InstancePtr);
if (!(InstancePtr->is_rxbs_error)) {
Event = XUARTPS_EVENT_RECV_ERROR;
EventData = InstancePtr->ReceiveBuffer.RequestedBytes -
InstancePtr->ReceiveBuffer.RemainingBytes;
/*
* Call the application handler to indicate that there is a receive
* error or a break interrupt, if the application cares about the
* error it call a function to get the last errors.
*/
InstancePtr->Handler(InstancePtr->CallBackRef,
Event,
EventData);
}
}
/**
*
* This function attempts to receive a specified number of bytes of data
* from the device and store it into the specified buffer. This function works
* for both polled or interrupt driven modes. It is non-blocking.
*
* In a polled mode, this function will only receive the data already in the
* RX FIFO. The application may need to call it repeatedly to receive the
* entire buffer. Polled mode is the default mode of operation for the device.
*
* In interrupt mode, this function will start the receiving, if not the entire
* buffer has been received, the interrupt handler will continue receiving data
* until the entire buffer has been received. A callback function, as specified
* by the application, will be called to indicate the completion of the
* receiving or error conditions.
*
* @param InstancePtr is a pointer to the XUartPs instance
* @param BufferPtr is pointer to buffer for data to be received into
* @param NumBytes is the number of bytes to be received. A value of zero
* will stop a previous receive operation that is in progress in
* interrupt mode.
*
* @return The number of bytes received.
*
* @note
*
* The number of bytes is not asserted so that this function may be called
* with a value of zero to stop an operation that is already in progress.
*
*****************************************************************************/
u32 XUartPs_Recv(XUartPs *InstancePtr,
u8 *BufferPtr, u32 NumBytes)
{
u32 ReceivedCount;
u32 ImrRegister;
/*
* Assert validates the input arguments
*/
Xil_AssertNonvoid(InstancePtr != NULL);
Xil_AssertNonvoid(BufferPtr != NULL);
Xil_AssertNonvoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
/*
* Disable all the interrupts.
* This stops a previous operation that may be interrupt driven
*/
ImrRegister = XUartPs_ReadReg(InstancePtr->Config.BaseAddress,
XUARTPS_IMR_OFFSET);
XUartPs_WriteReg(InstancePtr->Config.BaseAddress, XUARTPS_IDR_OFFSET,
XUARTPS_IXR_MASK);
/*
* Setup the buffer parameters
*/
InstancePtr->ReceiveBuffer.RequestedBytes = NumBytes;
InstancePtr->ReceiveBuffer.RemainingBytes = NumBytes;
InstancePtr->ReceiveBuffer.NextBytePtr = BufferPtr;
/*
* Receive the data from the device
*/
ReceivedCount = XUartPs_ReceiveBuffer(InstancePtr);
/*
* Restore the interrupt state
*/
XUartPs_WriteReg(InstancePtr->Config.BaseAddress, XUARTPS_IER_OFFSET,
ImrRegister);
return ReceivedCount;
}
/*
*
* This function handles interrupts for receive errors which include
* overrun errors, framing errors, parity errors, and the break interrupt.
*
* @param InstancePtr is a pointer to the XUartPs instance.
*
* @return None.
*
* @note None.
*
*****************************************************************************/
static void ReceiveErrorHandler(XUartPs *InstancePtr)
{
/*
* If there are bytes still to be received in the specified buffer
* go ahead and receive them. Removing bytes from the RX FIFO will
* clear the interrupt.
*/
if (InstancePtr->ReceiveBuffer.RemainingBytes != (u32)0) {
(void)XUartPs_ReceiveBuffer(InstancePtr);
}
/*
* Call the application handler to indicate that there is a receive
* error or a break interrupt, if the application cares about the
* error it call a function to get the last errors.
*/
InstancePtr->Handler(InstancePtr->CallBackRef,
XUARTPS_EVENT_RECV_ERROR,
(InstancePtr->ReceiveBuffer.RequestedBytes -
InstancePtr->ReceiveBuffer.RemainingBytes));
}
