/****************************************************************************
* arch/z80/src/ez80/ez80_loweruart.c
*
* Copyright (C) 2008, 2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name NuttX 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <string.h>
#include <arch/io.h>
#include <nuttx/arch.h>
#include <nuttx/sched.h>
#include "chip/chip.h"
#include "common/up_internal.h"
#ifdef CONFIG_USE_LOWUARTINIT
/****************************************************************************
* Private Definitions
****************************************************************************/
/* Is there any serial support? This might be the case if the board does
* not have serial ports but supports stdout through, say, an LCD.
*/
#if defined(CONFIG_UART0_DISABLE) || defined(CONFIG_UART1_DISABLE)
# define HAVE_SERIAL
#else
# undef HAVE_SERIAL
#endif
/* Is one of the serial ports a console? */
#if defined(CONFIG_UART0_SERIAL_CONSOLE) && !defined(CONFIG_UART0_DISABLE)
# define HAVE_SERIALCONSOLE 1
# undef CONFIG_UART1_SERIAL_CONSOLE
#elif defined(CONFIG_UART1_SERIAL_CONSOLE) && !defined(CONFIG_UART1_DISABLE)
# define HAVE_SERIALCONSOLE 1
# undef CONFIG_UART0_SERIAL_CONSOLE
#else
# warning "No console is defined"
# if defined(CONFIG_UART0_SERIAL_CONSOLE) || defined(CONFIG_UART1_SERIAL_CONSOLE)
# error "A serial console selected, but corresponding UART not enabled"
# endif
# undef CONFIG_UART0_SERIAL_CONSOLE
# undef CONFIG_UART1_SERIAL_CONSOLE
# undef HAVE_SERIALCONSOLE
#endif
/* Select UART parameters for the selected console */
#if defined(CONFIG_UART0_SERIAL_CONSOLE)
# define ez80_inp(offs) inp((EZ80_UART0_BASE+(offs)))
# define ez80_outp(offs,val) outp((EZ80_UART0_BASE+(offs)), (val))
# define CONFIG_UART_BAUD CONFIG_UART0_BAUD
# if CONFIG_UART0_BITS == 7
# define CONFIG_UART_BITS EZ80_UARTCHAR_7BITS
# else
# define CONFIG_UART_BITS EZ80_UARTCHAR_8BITS
# endif
# if CONFIG_UART0_2STOP != 0
# define CONFIG_UART_2STOP EZ80_UARTLCTl_2STOP
# else
# define CONFIG_UART_2STOP 0
# endif
# if CONFIG_UART0_PARITY == 1 /* Odd parity */
# define CONFIG_UART_PARITY EZ80_UARTLCTL_PEN
# elif CONFIG_UART0_PARITY == 2 /* Even parity */
# define CONFIG_UART_PARITY (EZ80_UARTLCTL_PEN|EZ80_UARTLCTL_EPS)
# else
# define CONFIG_UART_PARITY 0
# endif
#elif defined(CONFIG_UART0_SERIAL_CONSOLE)
# define ez80_inp(offs) inp((EZ80_UART1_BASE+(offs)))
# define ez80_outp(offs.val) outp((EZ80_UART1_BASE+(offs)), (val))
# define CONFIG_UART_BAUD CONFIG_UART1_BAUD
# if CONFIG_UART1_BITS == 7
# define CONFIG_UART_BITS EZ80_UARTCHAR_7BITS
# else
# define CONFIG_UART_BITS EZ80_UARTCHAR_8BITS
# endif
# if CONFIG_UART1_2STOP != 0
# define CONFIG_UART_2STOP EZ80_UARTLCTl_2STOP
# else
# define CONFIG_UART_2STOP 0
# endif
# if CONFIG_UART1_PARITY == 1 /* Odd parity */
# define CONFIG_UART_PARITY EZ80_UARTLCTL_PEN
# elif CONFIG_UART1_PARITY == 2 /* Even parity */
# define CONFIG_UART_PARITY (EZ80_UARTLCTL_PEN|EZ80_UARTLCTL_EPS)
# else
# define CONFIG_UART_PARITY 0
# endif
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
#if defined(HAVE_SERIALCONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
static void ez80_setbaud(void)
{
uint32 brg_divisor;
ubyte lctl;
/* The resulting BAUD and depends on the system clock frequency and the
* BRG divisor as follows:
*
* BAUD = SYSTEM_CLOCK_FREQUENCY / (16 * BRG_Divisor)
*
* Or
*
* BRG_Divisor = SYSTEM_CLOCK_FREQUENCY / 16 / BAUD
*
* NOTE: The system clock frequency value is defined in the board.h file
*/
brg_divisor = (ez80_systemclock + (CONFIG_UART_BAUD << 3)) / (CONFIG_UART_BAUD << 4);
/* Set the DLAB bit to enable access to the BRG registers */
lctl = ez80_inp(EZ80_UART_LCTL);
lctl |= EZ80_UARTLCTL_DLAB;
ez80_outp(EZ80_UART_LCTL, lctl);
ez80_outp(EZ80_UART_BRGL, (ubyte)(brg_divisor & 0xff));
ez80_outp(EZ80_UART_BRGH, (ubyte)(brg_divisor >> 8));
lctl &= ~EZ80_UARTLCTL_DLAB;
ez80_outp(EZ80_UART_LCTL, lctl);
}
#endif /* HAVE_SERIALCONSOLE && !CONFIG_SUPPRESS_UART_CONFIG */
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_lowuartinit
****************************************************************************/
void up_lowuartinit(void)
{
#ifdef HAVE_SERIAL
ubyte regval;
/* Configure pins for usage of UARTs (whether or not we have a console) */
#ifndef CONFIG_UART0_DISABLE
/* Set Port D, pins 0 and 1 for their alternate function (Mode 7) to enable UART0 */
regval = inp(EZ80_PD_DDR);
regval |= 3;
outp(EZ80_PD_DDR, regval);
regval = inp(EZ80_PD_ALT1);
regval &= ~3;
outp(EZ80_PD_ALT1, regval);
regval = inp(EZ80_PD_ALT2);
regval |= 3;
outp(EZ80_PD_ALT2, regval);
#endif
#ifndef CONFIG_UART1_DISABLE
/* Set Port C, pins 0 and 1 for their alternate function (Mode 7) to enable UART1 */
regval = inp(EZ80_PC_DDR);
regval |= 3;
outp(EZ80_PC_DDR, regval);
regval = inp(EZ80_PC_ALT1);
regval &= ~3;
outp(EZ80_PC_ALT1, regval);
regval = inp(EZ80_PC_ALT2);
regval |= 3;
outp(EZ80_PC_ALT2, regval);
#endif
#if defined(HAVE_SERIALCONSOLE) && !defined(CONFIG_SUPPRESS_UART_CONFIG)
/* Disable interrupts from the UART */
regval = ez80_inp(EZ80_UART_IER);
regval &= ~EZ80_UARTEIR_INTMASK;
ez80_outp(EZ80_UART_IER, regval);
/* Set the baud rate */
ez80_setbaud();
ez80_outp(EZ80_UART_MCTL, 0);
/* Set the character properties */
regval = ez80_inp(EZ80_UART_LCTL);
regval &= ~EZ80_UARTLCTL_MASK;
regval |= (CONFIG_UART_BITS | CONFIG_UART_2STOP | CONFIG_UART_PARITY);
ez80_outp(EZ80_UART_LCTL, regval);
/* Enable and flush the receive FIFO */
regval = EZ80_UARTFCTL_FIFOEN;
ez80_outp(EZ80_UART_FCTL, regval);
regval |= (EZ80_UARTFCTL_CLRTxF|EZ80_UARTFCTL_CLRRxF);
ez80_outp(EZ80_UART_FCTL, regval);
/* Set the receive trigger level to 1 */
regval |= EZ80_UARTTRIG_1;
ez80_outp(EZ80_UART_FCTL, regval);
#endif /* HAVE_SERIALCONSOLE && !CONFIG_SUPPRESS_UART_CONFIG */
#endif /* HAVE_SERIAL */
}
#endif /* CONFIG_USE_LOWUARTINIT */
