/**************************************************************************** * arch/arm/src/lpc2378/lpc23xx_serial.c * * Copyright (C) 2010 Rommel Marcelo. All rights reserved. * Author: Rommel Marcelo * With updates by: Gregory Nutt * * This file is part of the NuttX RTOS and based on the lpc2148 port: * * Copyright (C) 2010, 2012 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 "os_internal.h" #include "internal.h" #include "lpc23xx_scb.h" #include "lpc23xx_pinsel.h" #include "lpc23xx_uart.h" #include "lpc23xx_vic.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 ****************************************************************************/ 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_uart2rxbuffer[CONFIG_UART2_RXBUFSIZE]; static char g_uart2txbuffer[CONFIG_UART2_TXBUFSIZE]; /* This describes the state of the LPC214X uart0 port. */ #ifdef CONFIG_UART0 static struct up_dev_s g_uart0priv = { .uartbase = UART0_BASE_ADDR, .baud = CONFIG_UART0_BAUD, .irq = 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, }; #endif #ifdef CONFIG_UART2 /* This describes the state of the LPC23XX uart2 port. */ static struct up_dev_s g_uart2priv = { .uartbase = UART2_BASE_ADDR, .baud = CONFIG_UART2_BAUD, .irq = UART2_IRQ, .parity = CONFIG_UART2_PARITY, .bits = CONFIG_UART2_BITS, .stopbits2 = CONFIG_UART2_2STOP, }; static uart_dev_t g_uart2port = { .recv = { .size = CONFIG_UART2_RXBUFSIZE, .buffer = g_uart2rxbuffer, }, .xmit = { .size = CONFIG_UART2_TXBUFSIZE, .buffer = g_uart2txbuffer, }, .ops = &g_uart_ops, .priv = &g_uart2priv, }; #endif /* 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_uart2port #elif defined(CONFIG_UART1_SERIAL_CONSOLE) # define CONSOLE_DEV g_uart2port # define TTYS0_DEV g_uart2port # 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 & IER_ALLIE; } priv->ier &= ~IER_ALLIE; up_serialout(priv, UART_IER_OFFSET, priv->ier); } /**************************************************************************** * Name: up_restoreuartint ****************************************************************************/ static inline void up_restoreuartint(struct up_dev_s *priv, uint8_t ier) { priv->ier |= ier & IER_ALLIE; up_serialout(priv, 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, UART_LSR_OFFSET) & 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, UART_LCR_OFFSET); if (enable) { lcr |= LCR_BREAK_ENABLE; } else { lcr &= ~LCR_BREAK_ENABLE; } up_serialout(priv, UART_LCR_OFFSET, lcr); } /**************************************************************************** * Name: up_configbaud ****************************************************************************/ static inline void up_configbaud(struct up_dev_s *priv) { /* In a buckled-up, embedded system, there is no reason to constantly * calculate the following. The calculation can be skipped if the MULVAL, * DIVADDVAL, and DIVISOR values are provided in the configuration file. */ #ifndef CONFIG_UART_MULVAL uint32_t qtrclk; /* Test values calculated for every multiplier/divisor combination */ uint32_t tdiv; uint32_t terr; int tmulval; int tdivaddval; /* Optimal multiplier/divider values */ uint32_t div = 0; uint32_t err = 100000; int mulval = 1; int divaddval = 0; /* Baud is generated using FDR and DLL-DLM registers * * baud = clock * (mulval/(mulval+divaddval) / (16 * div) * * Or * * div = (clock/16) * (mulval/(mulval+divaddval) / baud * * Where mulval = Fractional divider multiplier * divaddval = Fractional divider pre-scale div * div = DLL-DLM divisor */ /* Get UART block clock divided by 16 */ qtrclk = U0_PCLK >> 4; /* TODO: Different Uart port with different clocking */ /* Try every valid multiplier, tmulval (or until a perfect match is found). */ for (tmulval = 1; tmulval <= 15 && err > 0; tmulval++) { /* Try every valid pre-scale div, tdivaddval (or until a perfect match is * found). */ for (tdivaddval = 0; tdivaddval <= 15 && err > 0; tdivaddval++) { /* Calculate the divisor with these fractional divider settings */ uint32_t tmp = (tmulval * qtrclk) / ((tmulval + tdivaddval)); tdiv = (tmp + (priv->baud >> 1)) / priv->baud; /* Check if this candidate divisor is within a valid range */ if (tdiv > 2 && tdiv < 0x10000) { /* Calculate the actual baud and the error */ uint32_t actualbaud = tmp / tdiv; if (actualbaud <= priv->baud) { terr = priv->baud - actualbaud; } else { terr = actualbaud - priv->baud; } /* Is this the smallest error we have encountered? */ if (terr < err) { /* Yes, save these settings as the new, candidate optimal * settings */ mulval = tmulval; divaddval = tdivaddval; div = tdiv; err = terr; } } } } /* Configure the MS and LS DLAB registers */ up_serialout(priv, UART_DLM_OFFSET, div >> 8); up_serialout(priv, UART_DLL_OFFSET, div & 0xff); /* Configure the Fractional Divider Register (FDR) */ up_serialout(priv, UART_FDR_OFFSET, ((mulval << 4) | divaddval)); #else /* Configure the MS and LS DLAB registers */ up_serialout(priv, UART_DLM_OFFSET, DLMVAL >> 8); up_serialout(priv, UART_DLL_OFFSET, DLLVAL & 0xff); /* Configure the Fractional Divider Register (FDR) */ up_serialout(priv, UART_FDR_OFFSET, ((MULVAL << 4) | DIVADDVAL)); #endif } /**************************************************************************** * 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; uint8_t lcr; /* Clear fifos */ up_serialout(priv, UART_FCR_OFFSET, (FCR_RX_FIFO_RESET | FCR_TX_FIFO_RESET)); /* Set trigger */ up_serialout(priv, UART_FCR_OFFSET, (FCR_FIFO_ENABLE | FCR_FIFO_TRIG14)); /* Set up the IER */ priv->ier = up_serialin(priv, UART_IER_OFFSET); /* Set up the Line Control Register */ lcr = 0; lcr |= (priv->bits == 7) ? LCR_CHAR_7 : LCR_CHAR_8; if (priv->stopbits2) { lcr |= LCR_STOP_2; } if (priv->parity == 1) { lcr |= LCR_PAR_ODD; } else if (priv->parity == 2) { lcr |= LCR_PAR_EVEN; } /* Enable access to latch divisor DLAB=1 */ up_serialout(priv, UART_LCR_OFFSET, (lcr | LCR_DLAB_ENABLE)); /* find values for DLL, DLM, DIVADDVAL, MULVAL */ up_configbaud(priv); /* Disable access to latch divisor Clear DLAB */ up_serialout(priv, UART_LCR_OFFSET, lcr); /* Configure the FIFOs */ up_serialout(priv, UART_FCR_OFFSET, (FCR_FIFO_TRIG8 | FCR_TX_FIFO_RESET | FCR_RX_FIFO_RESET | FCR_FIFO_ENABLE)); /* The NuttX serial driver waits for the first THRE interrrupt before sending * serial data... However, it appears that the LPC2378 hardware too 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, 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); /* Set the uart interrupt priority (the default value is one) */ if (priv->uartbase == UART0_BASE_ADDR) { up_prioritize_irq(priv->irq, PRIORITY_LOWEST); } else if (priv->uartbase == UART2_BASE_ADDR) { up_prioritize_irq(priv->irq, 10); } } 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_uart0priv.irq == irq) { dev = &g_uart0port; } else if (g_uart2priv.irq == irq) { dev = &g_uart2port; } 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, UART_IIR_OFFSET); /* The NO INTERRUPT should be zero if there are pending interrupts */ if ((status & 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 & IIR_MASK) { /* Handle incoming, receive bytes (with or without timeout) */ case IIR_RDA_INT: case IIR_CTI_INT: { uart_recvchars(dev); break; } /* Handle outgoing, transmit bytes */ case IIR_THRE_INT: { uart_xmitchars(dev); break; } /* Just clear modem status interrupts (UART1 only) */ case IIR_MS_INT: { /* Read the modem status register (MSR) to clear */ status = up_serialin(priv, UART_MSR_OFFSET); vdbg("MSR: %02x\n", status); break; } /* Just clear any line status interrupts */ case IIR_RLS_INT: { /* Read the line status register (LSR) to clear */ status = up_serialin(priv, 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) { ret = -EINVAL; } 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: 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, UART_LSR_OFFSET); rbr = up_serialin(priv, 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 |= IER_ERBFI; #endif } else { priv->ier &= ~IER_ERBFI; } up_serialout(priv, 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, UART_LSR_OFFSET) & 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, 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 |= IER_ETBEI; #endif } else { priv->ier &= ~IER_ETBEI; } up_serialout(priv, 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, UART_LSR_OFFSET) & 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, UART_LSR_OFFSET) & 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 2 */ uint32_t pinsel = getreg32(LPC23XX_PINSEL0); pinsel &= ~(UART0_PINMASK | UART2_PINMASK); pinsel |= (UART0_PINSEL | UART2_PINSEL); putreg32(pinsel, LPC23XX_PINSEL0); /* Set Uart PCLK divider */ SCB_PCLKSEL0 = (SCB_PCLKSEL0 & ~U0_PCLKSEL_MASK) | U0_PCLKSEL; SCB_PCLKSEL1 = (SCB_PCLKSEL1 & ~U2_PCLKSEL_MASK) | U2_PCLKSEL; /* 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, UART_THR_OFFSET, (uint8_t) ch); /* Check for LF */ if (ch == '\n') { /* Add CR */ up_waittxready(priv); up_serialout(priv, 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 */