/****************************************************************************
* arch/rgmp/src/x86/com.c
*
* Copyright (C) 2011 Yu Qiang. All rights reserved.
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Authors: Yu Qiang <yuq825@gmail.com>
* 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 <stdint.h>
#include <stdbool.h>
#include <unistd.h>
#include <semaphore.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/serial.h>
#include <nuttx/kmalloc.h>
#include <arch/com.h>
#include <rgmp/trap.h>
#include <rgmp/arch/console.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define COM1 0x3F8
#define COM2 0x2f8
#define COM3 0x3e8
#define COM4 0x2e8
#define COM_RX 0 // In: Receive buffer (DLAB=0)
#define COM_DLL 0 // Out: Divisor Latch Low (DLAB=1)
#define COM_TX 0 // Out: Transmit buffer (DLAB=0)
#define COM_DLM 1 // Out: Divisor Latch High (DLAB=1)
#define COM_IER 1 // Out: Interrupt Enable Register
#define COM_IER_TEI 0x02 // Enable transmit buffer empty interrupt
#define COM_IER_RDI 0x01 // Enable receiver data interrupt
#define COM_IIR 2 // In: Interrupt ID Register
#define COM_FCR 2 // Out: FIFO Control Register
#define COM_LCR 3 // Out: Line Control Register
#define COM_LCR_DLAB 0x80 // Divisor latch access bit
#define COM_LCR_WLEN8 0x03 // Wordlength: 8 bits
#define COM_MCR 4 // Out: Modem Control Register
#define COM_MCR_RTS 0x02 // RTS complement
#define COM_MCR_DTR 0x01 // DTR complement
#define COM_MCR_OUT2 0x08 // Out2 complement
#define COM_LSR 5 // In: Line Status Register
#define COM_LSR_DATA 0x01 // Data available
#define COM_LSR_ETR 0x20 // buffer has space
#define COM_LSR_EDR 0x40 // buffer empty
/****************************************************************************
* Private Types
****************************************************************************/
#ifndef CONFIG_COM_RXBUFSIZE
#define CONFIG_COM_RXBUFSIZE 64
#endif
#ifndef CONFIG_COM_TXBUFSIZE
#define CONFIG_COM_TXBUFSIZE 64
#endif
struct up_dev_s
{
unsigned int base; /* Base address of COM registers */
unsigned int baud; /* Configured baud */
int irq; /* IRQ associated with this COM */
struct irq_action action;
union {
uint8_t val;
struct {
unsigned bits : 2; /* 3=8 bits, 2=7 bits, 1=6 bits, 0=5 bits */
unsigned stopbits : 1; /* 0=1 stop bit, 1=2 stop bits */
unsigned parity : 3; /* xx0=none, 001=odd, 011=even */
unsigned ebreak : 1;
unsigned dlab : 1;
} sep;
} lcr;
char rxbuff[CONFIG_COM_RXBUFSIZE]; /* receive buffer */
char txbuff[CONFIG_COM_TXBUFSIZE]; /* transmit buffer */
};
/****************************************************************************
* 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 irqreturn_t up_com_int_handler(struct Trapframe *tf, void *dev_id);
static int up_ioctl(struct file *filep, int cmd, unsigned long arg);
static int up_receive(struct uart_dev_s *dev, unsigned int *status);
static void up_rxint(struct uart_dev_s *dev, bool enable);
static bool 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, bool enable);
static bool up_txready(struct uart_dev_s *dev);
static bool up_txempty(struct uart_dev_s *dev);
/****************************************************************************
* Private Variables
****************************************************************************/
static struct uart_ops_s g_com_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,
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_alloc_com
****************************************************************************/
static uart_dev_t *up_alloc_com(unsigned int base, int irq)
{
uart_dev_t *dev;
struct up_dev_s *priv;
priv = kzalloc(sizeof(struct up_dev_s));
if (priv == NULL)
goto err0;
dev = kzalloc(sizeof(uart_dev_t));
if (dev == NULL)
goto err1;
priv->base = base;
priv->irq = irq;
priv->baud = 115200;
priv->lcr.val = 0;
priv->lcr.sep.parity = 0;
priv->lcr.sep.bits = 3;
priv->lcr.sep.stopbits = 0;
priv->action.handler = up_com_int_handler;
priv->action.dev_id = dev;
dev->recv.size = CONFIG_COM_RXBUFSIZE;
dev->recv.buffer = priv->rxbuff;
dev->xmit.size = CONFIG_COM_TXBUFSIZE;
dev->xmit.buffer = priv->txbuff;
dev->ops = &g_com_ops;
dev->priv = priv;
return dev;
err1:
kfree(priv);
err0:
return NULL;
}
/****************************************************************************
* Name: up_alloc_com
****************************************************************************/
static inline void up_free_com(uart_dev_t *com)
{
kfree(com->priv);
kfree(com);
}
/****************************************************************************
* 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)
{
struct up_dev_s *priv = dev->priv;
uint16_t base = priv->base;
union {
uint16_t val;
struct {
uint8_t low;
uint8_t high;
} sep;
} data;
// clear and disable FIFO
outb(base+COM_FCR, 1);
outb(base+COM_FCR, 3);
outb(base+COM_FCR, 0);
// Clear any preexisting overrun indications and interrupts
// Serial port doesn't exist if COM_LSR returns 0xFF
inb(base+COM_LSR);
inb(base+COM_IIR);
inb(base+COM_RX);
if (inb(base+COM_LSR) == 0xff) {
dbg("COM %d does not exist\n", base);
return -1;
}
// Set speed; requires DLAB latch
outb(base+COM_LCR, COM_LCR_DLAB);
data.val = 115200 / priv->baud;
outb(base+COM_DLL, data.sep.low);
outb(base+COM_DLM, data.sep.high);
// set data bits, stop bit, parity; turn off DLAB latch
outb(base+COM_LCR, priv->lcr.val);
// OUT2 must be set to enable interrupt
outb(base+COM_MCR, COM_MCR_OUT2);
// setup FIFO
outb(base+COM_FCR, 1);
// disable COM interrupts
outb(base+COM_IER, 0);
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 = dev->priv;
uint16_t base = priv->base;
// disable COM interrupts
outb(base+COM_IER, 0);
}
/****************************************************************************
* 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 = dev->priv;
int err;
err = rgmp_request_irq(priv->irq, &priv->action, 0);
return err;
}
/****************************************************************************
* 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 = dev->priv;
rgmp_free_irq(priv->irq, &priv->action);
}
/****************************************************************************
* Name: up_com_int_handler
*
* 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 irqreturn_t up_com_int_handler(struct Trapframe *tf, void *dev_id)
{
struct uart_dev_s *dev = dev_id;
struct up_dev_s *priv = dev->priv;
uint16_t base = priv->base;
//uint8_t cause = inb(base+COM_IIR);
uint8_t state = inb(base+COM_LSR);
if (state & COM_LSR_DATA)
uart_recvchars(dev);
if (state & COM_LSR_ETR)
uart_xmitchars(dev);
return IRQ_HANDLED;
}
/****************************************************************************
* 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;
switch (cmd) {
case COM_SET_BAUD:
priv->baud = arg;
break;
case COM_SET_PARITY:
priv->lcr.sep.parity = arg;
break;
case COM_SET_STOPBITS:
priv->lcr.sep.stopbits = arg;
break;
case COM_SET_BITS:
priv->lcr.sep.bits = arg;
break;
default:
return ERROR;
}
if (up_setup(dev) != OK)
return ERROR;
up_rxint(dev, 1);
return OK;
}
/****************************************************************************
* 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, unsigned int *status)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16_t base = priv->base;
return inb(base+COM_RX);
}
/****************************************************************************
* Name: up_rxint
*
* Description:
* Call to enable or disable RX interrupts
*
****************************************************************************/
static void up_rxint(struct uart_dev_s *dev, bool enable)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16_t base = priv->base;
uint8_t ier;
ier = inb(base+COM_IER);
if (enable)
ier |= COM_IER_RDI;
else
ier &= ~COM_IER_RDI;
outb(base+COM_IER, ier);
}
/****************************************************************************
* Name: up_rxavailable
*
* Description:
* Return true if the receive fifo is not empty
*
****************************************************************************/
static bool up_rxavailable(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16_t base = priv->base;
return inb(base+COM_LSR) & COM_LSR_DATA;
}
/****************************************************************************
* 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;
uint16_t base = priv->base;
outb(base+COM_TX, ch);
}
/****************************************************************************
* Name: up_txint
*
* Description:
* Call to enable or disable TX interrupts
*
****************************************************************************/
static void up_txint(struct uart_dev_s *dev, bool enable)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16_t base = priv->base;
irqstate_t flags;
uint8_t ier;
flags = irqsave();
ier = inb(base+COM_IER);
if (enable) {
ier |= COM_IER_TEI;
outb(base+COM_IER, ier);
/* Fake a TX interrupt here by just calling uart_xmitchars() with
* interrupts disabled (note this may recurse).
*/
uart_xmitchars(dev);
}
else {
ier &= ~COM_IER_TEI;
outb(base+COM_IER, ier);
}
irqrestore(flags);
}
/****************************************************************************
* Name: up_txready
*
* Description:
* Return true if the tranmsit fifo is not full
*
****************************************************************************/
static bool up_txready(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16_t base = priv->base;
return inb(base+COM_LSR) & COM_LSR_ETR;
}
/****************************************************************************
* Name: up_txempty
*
* Description:
* Return true if the transmit fifo is empty
*
****************************************************************************/
static bool up_txempty(struct uart_dev_s *dev)
{
struct up_dev_s *priv = (struct up_dev_s*)dev->priv;
uint16_t base = priv->base;
return inb(base+COM_LSR) & COM_LSR_EDR;
}
/****************************************************************************
* 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)
{
}
/****************************************************************************
* Name: up_serialinit
*
* Description:
* Register serial console and serial ports. This assumes
* that up_earlyserialinit was called previously.
*
****************************************************************************/
void up_serialinit(void)
{
uart_dev_t *dev;
int err;
#ifdef CONFIG_COM1
dev = up_alloc_com(COM1, 4);
if (dev == NULL)
dbg("alloc com1 fail\n");
else {
err = uart_register("/dev/ttyS0", dev);
if (err)
dbg("register com1 fail\n");
}
#endif
#ifdef CONFIG_COM2
dev = up_alloc_com(COM2, 3);
if (dev == NULL)
dbg("alloc com2 fail\n");
else {
err = uart_register("/dev/ttyS1", dev);
if (err)
dbg("register com2 fail\n");
}
#endif
#ifdef CONFIG_COM3
dev = up_alloc_com(COM3, 4);
if (dev == NULL)
dbg("alloc com3 fail\n");
else {
err = uart_register("/dev/ttyS2", dev);
if (err)
dbg("register com3 fail\n");
}
#endif
#ifdef CONFIG_COM4
dev = up_alloc_com(COM4, 3);
if (dev == NULL)
dbg("alloc com4 fail\n");
else {
err = uart_register("/dev/ttyS3", dev);
if (err)
dbg("register com4 fail\n");
}
#endif
}
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug
* writes
*
****************************************************************************/
int up_putc(int ch)
{
cons_putc(ch);
return ch;
}
