openblt/Target/Source/ARMCM0_XMC1/uart.c

270 lines
11 KiB
C

/************************************************************************************//**
* \file Source\ARMCM0_XMC1\uart.c
* \brief Bootloader UART communication interface source file.
* \ingroup Target_ARMCM0_XMC1
* \internal
*----------------------------------------------------------------------------------------
* C O P Y R I G H T
*----------------------------------------------------------------------------------------
* Copyright (c) 2016 by Feaser http://www.feaser.com All rights reserved
*
*----------------------------------------------------------------------------------------
* L I C E N S E
*----------------------------------------------------------------------------------------
* This file is part of OpenBLT. OpenBLT 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.
*
* OpenBLT 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 have received a copy of the GNU General Public License along with OpenBLT. It
* should be located in ".\Doc\license.html". If not, contact Feaser to obtain a copy.
*
* \endinternal
****************************************************************************************/
/****************************************************************************************
* Include files
****************************************************************************************/
#include "boot.h" /* bootloader generic header */
#include "xmc_uart.h" /* UART driver header */
#if (BOOT_COM_UART_ENABLE > 0)
/****************************************************************************************
* Macro definitions
****************************************************************************************/
/** \brief Timeout time for the reception of a CTO packet. The timer is started upon
* reception of the first packet byte.
*/
#define UART_CTO_RX_PACKET_TIMEOUT_MS (100u)
/** \brief Timeout for transmitting a byte in milliseconds. */
#define UART_BYTE_TX_TIMEOUT_MS (10u)
/** \brief Macro for accessing the UART channel handle in the format that is expected
* by the XMClib UART driver.
*/
#define UART_CHANNEL ((XMC_USIC_CH_t *)(uartChannelMap[BOOT_COM_UART_CHANNEL_INDEX]))
/****************************************************************************************
* Local constant declarations
****************************************************************************************/
/** \brief Helper array to quickly convert the channel index, as specific in the boot-
* loader's configuration header, to the associated channel handle that the
* XMClib's UART driver requires.
*/
static const XMC_USIC_CH_t *uartChannelMap[] =
{
XMC_UART0_CH0, /* BOOT_COM_UART_CHANNEL_INDEX = 0 */
XMC_UART0_CH1, /* BOOT_COM_UART_CHANNEL_INDEX = 1 */
XMC_UART1_CH0, /* BOOT_COM_UART_CHANNEL_INDEX = 2 */
XMC_UART1_CH1 /* BOOT_COM_UART_CHANNEL_INDEX = 3 */
};
/****************************************************************************************
* Function prototypes
****************************************************************************************/
static blt_bool UartReceiveByte(blt_int8u *data);
static blt_bool UartTransmitByte(blt_int8u data);
/************************************************************************************//**
** \brief Initializes the UART communication interface.
** \return none.
**
****************************************************************************************/
void UartInit(void)
{
XMC_UART_CH_CONFIG_t uart_config;
/* the current implementation supports XMC_UART0_CH0 to XMC_UART2_CH1. throw an
* assertion error in case a different CAN channel is configured.
*/
ASSERT_CT((BOOT_COM_UART_CHANNEL_INDEX >= 0) && (BOOT_COM_UART_CHANNEL_INDEX <= 3));
/* set configuration and initialize UART channel */
uart_config.baudrate = BOOT_COM_UART_BAUDRATE;
uart_config.data_bits = 8;
uart_config.frame_length = 8;
uart_config.stop_bits = 1;
uart_config.oversampling = 16;
uart_config.parity_mode = XMC_USIC_CH_PARITY_MODE_NONE;
XMC_UART_CH_Init(UART_CHANNEL, &uart_config);
/* configure small transmit and receive FIFO */
XMC_USIC_CH_TXFIFO_Configure(UART_CHANNEL, 16U, XMC_USIC_CH_FIFO_SIZE_16WORDS, 1U);
XMC_USIC_CH_RXFIFO_Configure(UART_CHANNEL, 0U, XMC_USIC_CH_FIFO_SIZE_16WORDS, 1U);
/* start UART */
XMC_UART_CH_Start(UART_CHANNEL);
} /*** end of UartInit ***/
/************************************************************************************//**
** \brief Transmits a packet formatted for the communication interface.
** \param data Pointer to byte array with data that it to be transmitted.
** \param len Number of bytes that are to be transmitted.
** \return none.
**
****************************************************************************************/
void UartTransmitPacket(blt_int8u *data, blt_int8u len)
{
blt_int16u data_index;
blt_bool result;
/* verify validity of the len-parameter */
ASSERT_RT(len <= BOOT_COM_UART_TX_MAX_DATA);
/* first transmit the length of the packet */
result = UartTransmitByte(len);
ASSERT_RT(result == BLT_TRUE);
/* transmit all the packet bytes one-by-one */
for (data_index = 0; data_index < len; data_index++)
{
/* keep the watchdog happy */
CopService();
/* write byte */
result = UartTransmitByte(data[data_index]);
ASSERT_RT(result == BLT_TRUE);
}
} /*** end of UartTransmitPacket ***/
/************************************************************************************//**
** \brief Receives a communication interface packet if one is present.
** \param data Pointer to byte array where the data is to be stored.
** \param len Pointer where the length of the packet is to be stored.
** \return BLT_TRUE if a packet was received, BLT_FALSE otherwise.
**
****************************************************************************************/
blt_bool UartReceivePacket(blt_int8u *data, blt_int8u *len)
{
static blt_int8u xcpCtoReqPacket[BOOT_COM_UART_RX_MAX_DATA+1]; /* one extra for length */
static blt_int8u xcpCtoRxLength;
static blt_bool xcpCtoRxInProgress = BLT_FALSE;
static blt_int32u xcpCtoRxStartTime = 0;
/* start of cto packet received? */
if (xcpCtoRxInProgress == BLT_FALSE)
{
/* store the message length when received */
if (UartReceiveByte(&xcpCtoReqPacket[0]) == BLT_TRUE)
{
if ( (xcpCtoReqPacket[0] > 0) &&
(xcpCtoReqPacket[0] <= BOOT_COM_UART_RX_MAX_DATA) )
{
/* store the start time */
xcpCtoRxStartTime = TimerGet();
/* reset packet data count */
xcpCtoRxLength = 0;
/* indicate that a cto packet is being received */
xcpCtoRxInProgress = BLT_TRUE;
}
}
}
else
{
/* store the next packet byte */
if (UartReceiveByte(&xcpCtoReqPacket[xcpCtoRxLength+1]) == BLT_TRUE)
{
/* increment the packet data count */
xcpCtoRxLength++;
/* check to see if the entire packet was received */
if (xcpCtoRxLength == xcpCtoReqPacket[0])
{
/* copy the packet data */
CpuMemCopy((blt_int32u)data, (blt_int32u)&xcpCtoReqPacket[1], xcpCtoRxLength);
/* done with cto packet reception */
xcpCtoRxInProgress = BLT_FALSE;
/* set the packet length */
*len = xcpCtoRxLength;
/* packet reception complete */
return BLT_TRUE;
}
}
else
{
/* check packet reception timeout */
if (TimerGet() > (xcpCtoRxStartTime + UART_CTO_RX_PACKET_TIMEOUT_MS))
{
/* cancel cto packet reception due to timeout. note that that automaticaly
* discards the already received packet bytes, allowing the host to retry.
*/
xcpCtoRxInProgress = BLT_FALSE;
}
}
}
/* packet reception not yet complete */
return BLT_FALSE;
} /*** end of UartReceivePacket ***/
/************************************************************************************//**
** \brief Receives a communication interface byte if one is present.
** \param data Pointer to byte where the data is to be stored.
** \return BLT_TRUE if a byte was received, BLT_FALSE otherwise.
**
****************************************************************************************/
static blt_bool UartReceiveByte(blt_int8u *data)
{
if (XMC_USIC_CH_RXFIFO_IsEmpty(UART_CHANNEL) == 0)
{
/* retrieve and store the newly received byte */
*data = (blt_int8u)XMC_UART_CH_GetReceivedData(UART_CHANNEL);
/* all done */
return BLT_TRUE;
}
/* still here to no new byte received */
return BLT_FALSE;
} /*** end of UartReceiveByte ***/
/************************************************************************************//**
** \brief Transmits a communication interface byte.
** \param data Value of byte that is to be transmitted.
** \return BLT_TRUE if the byte was transmitted, BLT_FALSE otherwise.
**
****************************************************************************************/
static blt_bool UartTransmitByte(blt_int8u data)
{
blt_int32u timeout;
blt_bool result = BLT_TRUE;
/* check if tx fifo can accept new data */
if (XMC_USIC_CH_TXFIFO_IsFull(UART_CHANNEL) != 0)
{
/* tx fifo full. should not happen */
return BLT_FALSE;
}
/* submit data for transmission */
XMC_UART_CH_Transmit(UART_CHANNEL, data);
/* set timeout time to wait for transmit completion. */
timeout = TimerGet() + UART_BYTE_TX_TIMEOUT_MS;
/* wait for transmission to be done */
while( (XMC_USIC_CH_TXFIFO_GetEvent(UART_CHANNEL) & XMC_USIC_CH_TXFIFO_EVENT_STANDARD) == 0)
{
/* keep the watchdog happy */
CopService();
/* break loop upon timeout. this would indicate a hardware failure. */
if (TimerGet() > timeout)
{
result = BLT_FALSE;
break;
}
}
/* reset event */
XMC_USIC_CH_TXFIFO_ClearEvent(UART_CHANNEL, XMC_USIC_CH_TXFIFO_EVENT_STANDARD);
/* give the result back to the caller */
return result;
} /*** end of UartTransmitByte ***/
#endif /* BOOT_COM_UART_ENABLE > 0 */
/*********************************** end of uart.c *************************************/