/******************************************************************************
 * Copyright (c) 2011 Texas Instruments Incorporated - http://www.ti.com
 *
 *  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.
 *
 *****************************************************************************/

#include "evmc66x_uart.h"

static void uart_delay_cycles(uint32_t cycles)
{
	while (cycles--) {
		asm ("NOP");
	}
}

void uart_init(void)
{
	uint16_t uiBaudRate;
    uint8_t uiDLLVal = 0;
    uint8_t uiDLHVal = 0;

    // Allows access to the divisor latches of the baud generator during a
    // read or write operation (DLL and DLH)

    hUartRegs->LCR = 0x80;

    // Set the baudrate,for accessing LCR[7] should be enable
    hUartRegs->DLL  = DLL_VAL;
    hUartRegs->DLH  = DLM_VAL;

    // Allows access to the receiver buffer register (RBR),
    // the transmitter holding register (THR), and the
    // interrupt enable register (IER) selected.
    hUartRegs->LCR = 0x18;

    // Disable THR, RHR, Receiver line status interrupts
    hUartRegs->IER = 0;

    /* If autoflow control is desired,
    * write appropriate values to the modem
    * control register (MCR). Note that all UARTs
    * do not support autoflow control, see
    * the device-specific data manual for supported features.
    *
    * MCR
    * ====================================================
    * Bit  Field   Value   Description
    * 5    AFE     0       Autoflow control is disabled
    * 4    LOOP    0       Loop back mode is disabled.
    * 1    RTS     0       RTS control (UARTn_RTS is disabled,
    *                      UARTn_CTS is only enabled.)
    * =====================================================
    *
    *
    */

    hUartRegs->MCR = 0;

    /* Choose the desired response to
    * emulation suspend events by configuring
    * the FREE bit and enable the UART by setting
    * the UTRST and URRST bits in the power and
    * emulation management register (PWREMU_MGMT).
    *
    *
    * PWREMU_MGMT
    * =================================================
    * Bit  Field   Value   Description
    * 14   UTRST   1       Transmitter is enabled
    * 13   URRST   1       Receiver is enabled
    * 0    FREE    1       Free-running mode is enabled
    * ===================================================
    *
    */
    hUartRegs->PWREMU_MGMT = 0x6001;

    /* Cleanup previous data (rx trigger is also set to 0)*/
    /* Set FCR = 0x07;        */
    hUartRegs->FCR = 0xC1;

    /* Setting baud rate to 115200 */
    uiBaudRate = 88;

    /* Setting the baud rate */
    hUartRegs->LCR = 0x80;
    uiDLLVal = (uint8_t )(0x00FF & uiBaudRate);
    uiDLHVal = (uint8_t )(0x00FF & (uiBaudRate  >> 8));

    // Set the baudrate,for accessing LCR[7] should be enable
    hUartRegs->DLL  = uiDLLVal;
    hUartRegs->DLH  = uiDLHVal;
    hUartRegs->LCR  = 0x03;

    hUartRegs->LCR = 0x80;
    uiDLLVal = (uint8_t )(0x00FF & uiBaudRate);
    uiDLHVal = (uint8_t )(0x00FF & (uiBaudRate  >> 8));
    // Set the baudrate,for accessing LCR[7] should be enable
    hUartRegs->DLL  = uiDLLVal;
    hUartRegs->DLH  = uiDLHVal;
    hUartRegs->LCR = 0x03;

    return;
}

/******************************************************************************
 *
 * Function:	uart_write_byte
 *
 * Description:	This function writes a byte of data to UART device
 *
 * Parameters:	uint8_t uchAddress - Address of 8-bit register
 * 				uint8_t uchByte	-  8-bit data to write to THR
 *
 * Return Value: none
 ******************************************************************************/
static void uart_write_byte(uint8_t uchByte)
{
    while (!(hUartRegs->LSR & UART_LSR_THRE_MASK)) {
    	uart_delay_cycles(10000);
    }
    hUartRegs->THR = (UART_THR_DATA_MASK & uchByte);
    return;
}

void uart_write_string(uint8_t * str, uint32_t length)
{
	uint32_t i;
	uart_write_byte((uint8_t)0x0D);
	uart_write_byte((uint8_t)0x0A);
	for(i = 0; i < length; i++)
	{
		uart_write_byte(str[i]);
	}
}