/**************************************************************************** * arch/arm/src/lpc214x/lpc214x_serial.c * * Copyright (C) 2007-2009, 2012-2013 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 #include #include #include #include #include #include #include "chip.h" #include "up_arch.h" #include "up_internal.h" #include "lpc214x_pinsel.h" #include "lpc214x_uart.h" #ifdef USE_SERIALDRIVER /**************************************************************************** * Definitions ****************************************************************************/ /**************************************************************************** * Private Types ****************************************************************************/ struct up_dev_s { uint32_t uartbase; /* Base address of UART registers */ uint32_t baud; /* Configured baud */ uint8_t ier; /* Saved IER value */ uint8_t irq; /* IRQ associated with this UART */ uint8_t parity; /* 0=none, 1=odd, 2=even */ uint8_t bits; /* Number of bits (7 or 8) */ bool 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_t *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 const 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, #ifdef CONFIG_SERIAL_IFLOWCONTROL .rxflowcontrol = NULL, #endif .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 uint8_t 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, uint8_t value) { putreg8(value, priv->uartbase + offset); } /**************************************************************************** * Name: up_disableuartint ****************************************************************************/ static inline void up_disableuartint(struct up_dev_s *priv, uint8_t *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, uint8_t 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, bool enable) { uint8_t 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_UART_CONFIG struct up_dev_s *priv = (struct up_dev_s*)dev->priv; uint16_t baud; uint8_t 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)); /* The NuttX serial driver waits for the first THRE interrrupt before * sending serial data... However, it appears that the lpc214x hardware * does not generate that interrupt until a transition from not-empty * to empty. So, the current kludge here is to send one NULL at * startup to kick things off. */ up_serialout(priv, LPC214X_UART_THR_OFFSET, '\0'); #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; uint8_t status; int passes; if (g_uart1priv.irq == irq) { dev = &g_uart1port; } else if (g_uart0priv.irq == irq) { dev = &g_uart0port; } else { PANIC(); } 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) { #ifdef CONFIG_SERIAL_TIOCSERGSTRUCT case TIOCSERGSTRUCT: { struct up_dev_s *user = (struct up_dev_s*)arg; if (!user) { ret = -EINVAL; } else { memcpy(user, dev, sizeof(struct up_dev_s)); } } break; #endif 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: ret = -ENOTTY; 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 return 'status'. * ****************************************************************************/ static int up_receive(struct uart_dev_s *dev, uint32_t *status) { struct up_dev_s *priv = (struct up_dev_s*)dev->priv; uint8_t 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, bool 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 bool 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, (uint8_t)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; 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 bool 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 bool 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_t 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; uint8_t ier; up_disableuartint(priv, &ier); up_waittxready(priv); up_serialout(priv, LPC214X_UART_THR_OFFSET, (uint8_t)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 /* 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 /* USE_SERIALDRIVER */