/**************************************************************************** * arch/z80/src/ez80/ez80_loweruart.c * * Copyright (C) 2008, 2009 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #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 */