/****************************************************************************
* arch/arm/src/lpc214x/lpc214x_serial.c
*
* Copyright (C) 2007, 2008 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 <unistd.h>
#include <semaphore.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <nuttx/serial.h>
#include <arch/serial.h>
#include "up_arch.h"
#include "os_internal.h"
#include "up_internal.h"
#include "lpc214x_uart.h"
#ifdef CONFIG_USE_SERIALDRIVER
/****************************************************************************
* Definitions
****************************************************************************/
#define BASE_BAUD 38400
/****************************************************************************
* Private Types
****************************************************************************/
struct up_dev_s
{
uint32 uartbase; /* Base address of UART registers */
uint32 baud; /* Configured baud */
ubyte ier; /* Saved IER value */
ubyte irq; /* IRQ associated with this UART */
ubyte parity; /* 0=none, 1=odd, 2=even */
ubyte bits; /* Number of bits (7 or 8) */
boolean stopbits2; /* TRUE: Configure with 2 stop bits instead of 1 */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static int up_setup(struct uart_dev_s *dev);
static void up_shutdown(struct uart_dev_s *dev);
static int up_attach(struct uart_dev_s *dev);
static void up_detach(struct uart_dev_s *dev);
static int up_interrupt(int irq, void *context);
static int up_ioctl(struct file *filep, int cmd, unsigned long arg);
static int up_receive(struct uart_dev_s *dev, uint32 *status);
static void up_rxint(struct uart_dev_s *dev, boolean enable);
static boolean up_rxavailable(struct uart_dev_s *dev);
static void up_send(struct uart_dev_s *dev, int ch);
static void up_txint(struct uart_dev_s *dev, boolean enable);
static boolean up_txready(struct uart_dev_s *dev);
static boolean up_txempty(struct uart_dev_s *dev);
/****************************************************************************
* Private Variables
****************************************************************************/
struct uart_ops_s g_uart_ops =
{
.setup = up_setup,
.shutdown = up_shutdown,
.attach = up_attach,
.detach = up_detach,
.ioctl = up_ioctl,
.receive = up_receive,
.rxint = up_rxint,
.rxavailable = up_rxavailable,
.send = up_send,
.txint = up_txint,
.txready = up_txready,
.txempty = up_txempty,
};
/* I/O buffers */
static char g_uart0rxbuffer[CONFIG_UART0_RXBUFSIZE];
static char g_uart0txbuffer[CONFIG_UART0_TXBUFSIZE];
static char g_uart1rxbuffer[CONFIG_UART1_RXBUFSIZE];
static char g_uart1txbuffer[CONFIG_UART1_TXBUFSIZE];
/* This describes the state of the LPC214X uart0 port. */
static struct up_dev_s g_uart0priv =
{
.uartbase = LPC214X_UART0_BASE,
.baud = CONFIG_UART0_BAUD,
.irq = LPC214X_UART0_IRQ,
.parity = CONFIG_UART0_PARITY,
.bits = CONFIG_UART0_BITS,
.stopbits2 = CONFIG_UART0_2STOP,
};
static uart_dev_t g_uart0port =
{
.recv =
{
.size = CONFIG_UART0_RXBUFSIZE,
.buffer = g_uart0rxbuffer,
},
.xmit =
{
.size = CONFIG_UART0_TXBUFSIZE,
.buffer = g_uart0txbuffer,
},
.ops = &g_uart_ops,
.priv = &g_uart0priv,
};
/* This describes the state of the LPC214X uart1 port. */
static struct up_dev_s g_uart1priv =
{
.uartbase = LPC214X_UART1_BASE,
.baud = CONFIG_UART1_BAUD,
.irq = LPC214X_UART1_IRQ,
.parity = CONFIG_UART1_PARITY,
.bits = CONFIG_UART1_BITS,
.stopbits2 = CONFIG_UART1_2STOP,
};
static uart_dev_t g_uart1port =
{
.recv =
{
.size = CONFIG_UART1_RXBUFSIZE,
.buffer = g_uart1rxbuffer,
},
.xmit =
{
.size = CONFIG_UART1_TXBUFSIZE,
.buffer = g_uart1txbuffer,
},
.ops = &g_uart_ops,
.priv = &g_uart1priv,
};
/* Now, which one with be tty0/console and which tty1? */
#if defined(CONFIG_UART0_SERIAL_CONSOLE)
# define CONSOLE_DEV g_uart0port
# define TTYS0_DEV g_uart0port
# define TTYS1_DEV g_uart1port
#elif defined(CONFIG_UART1_SERIAL_CONSOLE)
# define CONSOLE_DEV g_uart1port
# define TTYS0_DEV g_uart1port
# define TTYS1_DEV g_uart0port
#else
# error "No CONFIG_UARTn_SERIAL_CONSOLE Setting"
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_serialin
****************************************************************************/
static inline ubyte up_serialin(struct up_dev_s *priv, int offset)
{
return getreg8(priv->uartbase + offset);
}
/****************************************************************************
* Name: up_serialout
****************************************************************************/
static inline void up_serialout(struct up_dev_s *priv, int offset, ubyte value)
{
putreg8(value, priv->uartbase + offset);
}
/****************************************************************************
* Name: up_disableuartint
****************************************************************************/
static inline void up_disableuartint(struct up_dev_s *priv, ubyte *ier)
{
if (ier)
{
*ier = priv->ier & LPC214X_IER_ALLIE;
}
priv->ier &= ~LPC214X_IER_ALLIE;
up_serialout(priv, LPC214X_UART_IER_OFFSET, priv->ier);
}
/****************************************************************************
* Name: up_restoreuartint
****************************************************************************/
static inline void up_restoreuartint(struct up_dev_s *priv, ubyte ier)
{
priv->ier |= ier & LPC214X_IER_ALLIE;
up_serialout(priv, LPC214X_UART_IER_OFFSET, priv->ier);
}
/****************************************************************************
* Name: up_waittxready
****************************************************************************/
static inline void up_waittxready(struct up_dev_s *priv)
{
int tmp;
/* Limit how long we will wait for the TX available condition */
for (tmp = 1000 ; tmp > 0 ; tmp--)
{
/* Check if the tranmitter holding register (THR) is empty */
if ((up_serialin(priv, LPC214X_UART_LSR_OFFSET) & LPC214X_LSR_THRE) != 0)
{
/* The THR is empty, return */
break;
}
}
}
/****************************************************************************
* Name: up_enablebreaks
****************************************************************************/
static inline void up_enablebreaks(struct up_dev_s *priv, boolean enable)
{
ubyte lcr = up_serialin(priv, LPC214X_UART_LCR_OFFSET);
if (enable)
{
lcr |= LPC214X_LCR_BREAK_ENABLE;
}
else
{
lcr &= ~LPC214X_LCR_BREAK_ENABLE;
}
up_serialout(priv, LPC214X_UART_LCR_OFFSET, lcr);
}
/****************************************************************************
* Name: up_setup
*
* Description:
* Configure the UART baud, bits, parity, fifos, etc. This
* method is called the first time that the serial port is
* opened.
*
****************************************************************************/
static int up_setup(struct uart_dev_s *dev)
{
#ifndef CONFIG_SUPPRESS_LPC214X_UART_CONFIG
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16 baud;
ubyte lcr;
/* Clear fifos */
up_serialout(priv, LPC214X_UART_FCR_OFFSET,
(LPC214X_FCR_RX_FIFO_RESET|LPC214X_FCR_TX_FIFO_RESET));
/* Set trigger */
up_serialout(priv, LPC214X_UART_FCR_OFFSET,
(LPC214X_FCR_FIFO_ENABLE|LPC214X_FCR_FIFO_TRIG14));
/* Set up the IER */
priv->ier = up_serialin(priv, LPC214X_UART_IER_OFFSET);
/* Set up the LCR */
lcr = 0;
if (priv->bits == 7)
{
lcr |= LPC214X_LCR_CHAR_7;
}
else
{
lcr |= LPC214X_LCR_CHAR_8;
}
if (priv->stopbits2)
{
lcr |= LPC214X_LCR_STOP_2;
}
if (priv->parity == 1)
{
lcr |= LPC214X_LCR_PAR_ODD;
}
else if (priv->parity == 2)
{
lcr |= LPC214X_LCR_PAR_EVEN;
}
/* Enter DLAB=1 */
up_serialout(priv, LPC214X_UART_LCR_OFFSET,
(lcr | LPC214X_LCR_DLAB_ENABLE));
/* Set the BAUD divisor */
baud = UART_BAUD(priv->baud);
up_serialout(priv, LPC214X_UART_DLM_OFFSET, baud >> 8);
up_serialout(priv, LPC214X_UART_DLL_OFFSET, baud & 0xff);
/* Clear DLAB */
up_serialout(priv, LPC214X_UART_LCR_OFFSET, lcr);
/* Configure the FIFOs */
up_serialout(priv, LPC214X_UART_FCR_OFFSET,
(LPC214X_FCR_FIFO_TRIG8|LPC214X_FCR_TX_FIFO_RESET|\
LPC214X_FCR_RX_FIFO_RESET|LPC214X_FCR_FIFO_ENABLE));
#endif
return OK;
}
/****************************************************************************
* Name: up_shutdown
*
* Description:
* Disable the UART. This method is called when the serial
* port is closed
*
****************************************************************************/
static void up_shutdown(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
up_disableuartint(priv, NULL);
}
/****************************************************************************
* Name: up_attach
*
* Description:
* Configure the UART to operation in interrupt driven mode. This method is
* called when the serial port is opened. Normally, this is just after the
* the setup() method is called, however, the serial console may operate in
* a non-interrupt driven mode during the boot phase.
*
* RX and TX interrupts are not enabled when by the attach method (unless the
* hardware supports multiple levels of interrupt enabling). The RX and TX
* interrupts are not enabled until the txint() and rxint() methods are called.
*
****************************************************************************/
static int up_attach(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
int ret;
/* Attach and enable the IRQ */
ret = irq_attach(priv->irq, up_interrupt);
if (ret == OK)
{
/* Enable the interrupt (RX and TX interrupts are still disabled
* in the UART
*/
up_enable_irq(priv->irq);
}
return ret;
}
/****************************************************************************
* Name: up_detach
*
* Description:
* Detach UART interrupts. This method is called when the serial port is
* closed normally just before the shutdown method is called. The exception is
* the serial console which is never shutdown.
*
****************************************************************************/
static void up_detach(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
up_disable_irq(priv->irq);
irq_detach(priv->irq);
}
/****************************************************************************
* Name: up_interrupt
*
* Description:
* This is the UART interrupt handler. It will be invoked
* when an interrupt received on the 'irq' It should call
* uart_transmitchars or uart_receivechar to perform the
* appropriate data transfers. The interrupt handling logic\
* must be able to map the 'irq' number into the approprite
* uart_dev_s structure in order to call these functions.
*
****************************************************************************/
static int up_interrupt(int irq, void *context)
{
struct uart_dev_s *dev = NULL;
struct up_dev_s *priv;
ubyte status;
int passes;
if (g_uart1priv.irq == irq)
{
dev = &g_uart1port;
}
else if (g_uart0priv.irq == irq)
{
dev = &g_uart0port;
}
else
{
PANIC(OSERR_INTERNAL);
}
priv = (struct up_dev_s*)dev->priv;
/* Loop until there are no characters to be transferred or,
* until we have been looping for a long time.
*/
for (passes = 0; passes < 256; passes++)
{
/* Get the current UART status and check for loop
* termination conditions
*/
status = up_serialin(priv, LPC214X_UART_IIR_OFFSET);
/* The NO INTERRUPT should be zero if there are pending
* interrupts
*/
if ((status & LPC214X_IIR_NO_INT) != 0)
{
/* Break out of the loop when there is no longer a
* pending interrupt
*/
break;
}
/* Handle the interrupt by its interrupt ID field */
switch (status & LPC214X_IIR_MASK)
{
/* Handle incoming, receive bytes (with or without timeout) */
case LPC214X_IIR_RDA_INT:
case LPC214X_IIR_CTI_INT:
{
uart_recvchars(dev);
break;
}
/* Handle outgoing, transmit bytes */
case LPC214X_IIR_THRE_INT:
{
uart_xmitchars(dev);
break;
}
/* Just clear modem status interrupts (UART1 only) */
case LPC214X_IIR_MS_INT:
{
/* Read the modem status register (MSR) to clear */
status = up_serialin(priv, LPC214X_UART_MSR_OFFSET);
vdbg("MSR: %02x\n", status);
break;
}
/* Just clear any line status interrupts */
case LPC214X_IIR_RLS_INT:
{
/* Read the line status register (LSR) to clear */
status = up_serialin(priv, LPC214X_UART_LSR_OFFSET);
vdbg("LSR: %02x\n", status);
break;
}
/* There should be no other values */
default:
{
dbg("Unexpected IIR: %02x\n", status);
break;
}
}
}
return OK;
}
/****************************************************************************
* Name: up_ioctl
*
* Description:
* All ioctl calls will be routed through this method
*
****************************************************************************/
static int up_ioctl(struct file *filep, int cmd, unsigned long arg)
{
struct inode *inode = filep->f_inode;
struct uart_dev_s *dev = inode->i_private;
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
int ret = OK;
switch (cmd)
{
case TIOCSERGSTRUCT:
{
struct up_dev_s *user = (struct up_dev_s*)arg;
if (!user)
{
*get_errno_ptr() = EINVAL;
ret = ERROR;
}
else
{
memcpy(user, dev, sizeof(struct up_dev_s));
}
}
break;
case TIOCSBRK: /* BSD compatibility: Turn break on, unconditionally */
{
irqstate_t flags = irqsave();
up_enablebreaks(priv, TRUE);
irqrestore(flags);
}
break;
case TIOCCBRK: /* BSD compatibility: Turn break off, unconditionally */
{
irqstate_t flags;
flags = irqsave();
up_enablebreaks(priv, FALSE);
irqrestore(flags);
}
break;
default:
*get_errno_ptr() = ENOTTY;
ret = ERROR;
break;
}
return ret;
}
/****************************************************************************
* Name: up_receive
*
* Description:
* Called (usually) from the interrupt level to receive one
* character from the UART. Error bits associated with the
* receipt are provided in the the return 'status'.
*
****************************************************************************/
static int up_receive(struct uart_dev_s *dev, uint32 *status)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
ubyte rbr;
*status = up_serialin(priv, LPC214X_UART_LSR_OFFSET);
rbr = up_serialin(priv, LPC214X_UART_RBR_OFFSET);
return rbr;
}
/****************************************************************************
* Name: up_rxint
*
* Description:
* Call to enable or disable RX interrupts
*
****************************************************************************/
static void up_rxint(struct uart_dev_s *dev, boolean enable)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
if (enable)
{
#ifndef CONFIG_SUPPRESS_SERIAL_INTS
priv->ier |= LPC214X_IER_ERBFI;
#endif
}
else
{
priv->ier &= ~LPC214X_IER_ERBFI;
}
up_serialout(priv, LPC214X_UART_IER_OFFSET, priv->ier);
}
/****************************************************************************
* Name: up_rxavailable
*
* Description:
* Return TRUE if the receive fifo is not empty
*
****************************************************************************/
static boolean up_rxavailable(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
return ((up_serialin(priv, LPC214X_UART_LSR_OFFSET) & LPC214X_LSR_RDR) != 0);
}
/****************************************************************************
* Name: up_send
*
* Description:
* This method will send one byte on the UART
*
****************************************************************************/
static void up_send(struct uart_dev_s *dev, int ch)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
up_serialout(priv, LPC214X_UART_THR_OFFSET, (ubyte)ch);
}
/****************************************************************************
* Name: up_txint
*
* Description:
* Call to enable or disable TX interrupts
*
****************************************************************************/
static void up_txint(struct uart_dev_s *dev, boolean enable)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
if (enable)
{
#ifndef CONFIG_SUPPRESS_SERIAL_INTS
priv->ier |= LPC214X_IER_ETBEI;
#endif
}
else
{
priv->ier &= ~LPC214X_IER_ETBEI;
}
up_serialout(priv, LPC214X_UART_IER_OFFSET, priv->ier);
}
/****************************************************************************
* Name: up_txready
*
* Description:
* Return TRUE if the tranmsit fifo is not full
*
****************************************************************************/
static boolean up_txready(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
return ((up_serialin(priv, LPC214X_UART_LSR_OFFSET) & LPC214X_LSR_THRE) != 0);
}
/****************************************************************************
* Name: up_txempty
*
* Description:
* Return TRUE if the transmit fifo is empty
*
****************************************************************************/
static boolean up_txempty(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
return ((up_serialin(priv, LPC214X_UART_LSR_OFFSET) & LPC214X_LSR_THRE) != 0);
}
/****************************************************************************
* Public Funtions
****************************************************************************/
/****************************************************************************
* Name: up_serialinit
*
* Description:
* Performs the low level UART initialization early in
* debug so that the serial console will be available
* during bootup. This must be called before up_serialinit.
*
****************************************************************************/
void up_earlyserialinit(void)
{
/* Enable UART0 and 1 */
uint32 pinsel = getreg32(LPC214X_PINSEL0);
pinsel &= ~(LPC214X_UART0_PINMASK|LPC214X_UART1_PINMASK);
pinsel |= (LPC214X_UART0_PINSEL|LPC214X_UART1_PINSEL);
putreg32(pinsel, LPC214X_PINSEL0);
/* Disable both UARTS */
up_disableuartint(TTYS0_DEV.priv, NULL);
up_disableuartint(TTYS1_DEV.priv, NULL);
/* Configuration whichever one is the console */
CONSOLE_DEV.isconsole = TRUE;
up_setup(&CONSOLE_DEV);
}
/****************************************************************************
* Name: up_serialinit
*
* Description:
* Register serial console and serial ports. This assumes
* that up_earlyserialinit was called previously.
*
****************************************************************************/
void up_serialinit(void)
{
(void)uart_register("/dev/console", &CONSOLE_DEV);
(void)uart_register("/dev/ttyS0", &TTYS0_DEV);
(void)uart_register("/dev/ttyS1", &TTYS1_DEV);
}
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug writes
*
****************************************************************************/
int up_putc(int ch)
{
struct up_dev_s *priv = (struct up_dev_s*)CONSOLE_DEV.priv;
ubyte ier;
up_disableuartint(priv, &ier);
up_waittxready(priv);
up_serialout(priv, LPC214X_UART_THR_OFFSET, (ubyte)ch);
/* Check for LF */
if (ch == '\n')
{
/* Add CR */
up_waittxready(priv);
up_serialout(priv, LPC214X_UART_THR_OFFSET, '\r');
}
up_waittxready(priv);
up_restoreuartint(priv, ier);
return ch;
}
#else /* CONFIG_USE_SERIALDRIVER */
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug writes
*
****************************************************************************/
int up_putc(int ch)
{
/* Check for LF */
if (ch == '\n')
{
/* Add CR */
up_lowputc('\r');
}
up_lowputc(ch);
return ch;
}
#endif /* CONFIG_USE_SERIALDRIVER */