/**************************************************************************** * arch/arm/src/sama5/sam_dbgu.c * * Copyright (C) 2014 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 "arm_arch.h" #include "arm_internal.h" #include "chip.h" #include "hardware/sam_dbgu.h" #include "hardware/sam_pinmap.h" #include "sam_pio.h" #include "sam_dbgu.h" #ifdef CONFIG_SAMA5_DBGU /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * Private Types ****************************************************************************/ #ifdef USE_SERIALDRIVER struct dbgu_dev_s { uint32_t sr; /* Saved status bits */ }; #endif /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static int dbgu_setup(struct uart_dev_s *dev); #ifdef USE_SERIALDRIVER static void dbgu_shutdown(struct uart_dev_s *dev); static int dbgu_attach(struct uart_dev_s *dev); static void dbgu_detach(struct uart_dev_s *dev); static int dbgu_interrupt(int irq, void *context, FAR void *arg); static int dbgu_ioctl(struct file *filep, int cmd, unsigned long arg); static int dbgu_receive(struct uart_dev_s *dev, unsigned int *status); static void dbgu_rxint(struct uart_dev_s *dev, bool enable); static bool dbgu_rxavailable(struct uart_dev_s *dev); static void dbgu_send(struct uart_dev_s *dev, int ch); static void dbgu_txint(struct uart_dev_s *dev, bool enable); static bool dbgu_txready(struct uart_dev_s *dev); static bool dbgu_txempty(struct uart_dev_s *dev); /**************************************************************************** * Private Data ****************************************************************************/ static const struct uart_ops_s g_uart_ops = { .setup = dbgu_setup, .shutdown = dbgu_shutdown, .attach = dbgu_attach, .detach = dbgu_detach, .ioctl = dbgu_ioctl, .receive = dbgu_receive, .rxint = dbgu_rxint, .rxavailable = dbgu_rxavailable, #ifdef CONFIG_SERIAL_IFLOWCONTROL .rxflowcontrol = NULL, #endif .send = dbgu_send, .txint = dbgu_txint, .txready = dbgu_txready, .txempty = dbgu_txempty, }; /* DBGU I/O buffers */ static char g_dbgu_rxbuffer[CONFIG_SAMA5_DBGU_RXBUFSIZE]; static char g_dbgu_txbuffer[CONFIG_SAMA5_DBGU_TXBUFSIZE]; /* This describes the private state of the DBGU port */ static struct dbgu_dev_s g_dbgu_priv; /* This describes the state of the DBGU port as is visible from the upper * half serial driver. */ static uart_dev_t g_dbgu_port = { .recv = { .size = CONFIG_SAMA5_DBGU_RXBUFSIZE, .buffer = g_dbgu_rxbuffer, }, .xmit = { .size = CONFIG_SAMA5_DBGU_TXBUFSIZE, .buffer = g_dbgu_txbuffer, }, .ops = &g_uart_ops, .priv = &g_dbgu_priv, }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: dbgu_configure * * Description: * Configure the DBGU baud, bits, parity, etc. This method is called the * first time that the serial port is opened. * ****************************************************************************/ #if !defined(CONFIG_SUPPRESS_UART_CONFIG) && !defined(CONFIG_SAMA5_DBGU_NOCONFIG) static void dbgu_configure(void) { uint32_t regval; /* Set up the mode register. Start with normal DBGU mode and the MCK * as the timing source */ regval = DBGU_MR_CHMODE_NORMAL; /* OR in settings for the selected parity */ #if CONFIG_SAMA5_DBGU_PARITY == 1 regval |= DBGU_MR_PAR_ODD; #elif CONFIG_SAMA5_DBGU_PARITY == 2 regval |= DBGU_MR_PAR_EVEN; #else regval |= DBGU_MR_PAR_NONE; #endif /* And save the new mode register value */ putreg32(regval, SAM_DBGU_MR); /* Configure the console baud. NOTE: Oversampling by 8 is not supported. * This may limit BAUD rates for lower DBGU clocks. */ regval = (BOARD_MCK_FREQUENCY + (CONFIG_SAMA5_DBGU_BAUD << 3)) / (CONFIG_SAMA5_DBGU_BAUD << 4); putreg32(regval, SAM_DBGU_BRGR); /* Enable receiver & transmitter */ putreg32((DBGU_CR_RXEN | DBGU_CR_TXEN), SAM_DBGU_CR); } #else # define dbgu_configure() #endif /* !CONFIG_SUPPRESS_UART_CONFIG && !CONFIG_SAMA5_DBGU_NOCONFIG */ /**************************************************************************** * Name: dbgu_setup * * Description: * Configure the DBGU baud, bits, parity, etc. This method is called the * first time that the serial port is opened. * ****************************************************************************/ static int dbgu_setup(struct uart_dev_s *dev) { #ifndef CONFIG_SUPPRESS_UART_CONFIG /* The shutdown method will put the DBGU in a known, disabled state */ dbgu_shutdown(dev); /* Then configure the DBGU */ dbgu_configure(); #endif return OK; } /**************************************************************************** * Name: dbgu_shutdown * * Description: * Disable the DBGU. This method is called when the serial * port is closed * ****************************************************************************/ static void dbgu_shutdown(struct uart_dev_s *dev) { #if !defined(CONFIG_SUPPRESS_UART_CONFIG) && !defined(CONFIG_SAMA5_DBGU_NOCONFIG) /* Disable all interrupts */ putreg32(DBGU_INT_ALLINTS, SAM_DBGU_IDR); #else irqstate_t flags; /* The following must be atomic */ flags = enter_critical_section(); /* Reset and disable receiver and transmitter */ putreg32((DBGU_CR_RSTRX | DBGU_CR_RSTTX | DBGU_CR_RXDIS | DBGU_CR_TXDIS), SAM_DBGU_CR); /* Disable all interrupts */ putreg32(DBGU_INT_ALLINTS, SAM_DBGU_IDR); leave_critical_section(flags); #endif } /**************************************************************************** * Name: dbgu_attach * * Description: * Configure the DBGU to operation in interrupt driven mode. This method * is called when the serial port is opened. Normally, this is just after * 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 dbgu_attach(struct uart_dev_s *dev) { int ret; /* Attach and enable the IRQ */ ret = irq_attach(SAM_IRQ_DBGU, dbgu_interrupt, dev); if (ret == OK) { /* Enable the interrupt (RX and TX interrupts are still disabled * in the DBGU */ up_enable_irq(SAM_IRQ_DBGU); } return ret; } /**************************************************************************** * Name: dbgu_detach * * Description: * Detach DBGU 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 dbgu_detach(struct uart_dev_s *dev) { up_disable_irq(SAM_IRQ_DBGU); irq_detach(SAM_IRQ_DBGU); } /**************************************************************************** * Name: dbgu_interrupt * * Description: * This is the DBGU 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 * appropriate uart_dev_s structure in order to call these functions. * ****************************************************************************/ static int dbgu_interrupt(int irq, void *context, FAR void *arg) { struct uart_dev_s *dev = (struct uart_dev_s *)arg; struct dbgu_dev_s *priv; uint32_t pending; uint32_t imr; int passes; bool handled; DEBUGASSERT(dev != NULL && dev->priv != NULL); priv = (struct dbgu_dev_s *)dev->priv; /* Loop until there are no characters to be transferred or, until we have * been looping for a long time. */ handled = true; for (passes = 0; passes < 256 && handled; passes++) { handled = false; /* Get the DBGU/DBGU status (we are only interested in the unmasked * interrupts). */ priv->sr = getreg32(SAM_DBGU_SR); /* Save for error reporting */ imr = getreg32(SAM_DBGU_IMR); /* Interrupt mask */ pending = priv->sr & imr; /* Mask out disabled interrupt sources */ /* Handle an incoming, receive byte. RXRDY: At least one complete * character has been received and US_RHR has not yet been read. */ if ((pending & DBGU_INT_RXRDY) != 0) { /* Received data ready... process incoming bytes */ uart_recvchars(dev); handled = true; } /* Handle outgoing, transmit bytes. XRDY: There is no character in the * US_THR. */ if ((pending & DBGU_INT_TXRDY) != 0) { /* Transmit data register empty ... process outgoing bytes */ uart_xmitchars(dev); handled = true; } } return OK; } /**************************************************************************** * Name: dbgu_ioctl * * Description: * All ioctl calls will be routed through this method * ****************************************************************************/ static int dbgu_ioctl(struct file *filep, int cmd, unsigned long arg) { #ifdef CONFIG_SERIAL_TIOCSERGSTRUCT struct inode *inode = filep->f_inode; struct uart_dev_s *dev = inode->i_private; #endif int ret = OK; switch (cmd) { #ifdef CONFIG_SERIAL_TIOCSERGSTRUCT case TIOCSERGSTRUCT: { struct dbgu_dev_s *user = (struct dbgu_dev_s *)arg; if (!user) { ret = -EINVAL; } else { memcpy(user, dev, sizeof(struct dbgu_dev_s)); } } break; #endif default: ret = -ENOTTY; break; } return ret; } /**************************************************************************** * Name: dbgu_receive * * Description: * Called (usually) from the interrupt level to receive one * character from the DBGU. Error bits associated with the * receipt are provided in the return 'status'. * ****************************************************************************/ static int dbgu_receive(struct uart_dev_s *dev, unsigned int *status) { struct dbgu_dev_s *priv = (struct dbgu_dev_s *)dev->priv; /* Return the error information in the saved status */ *status = priv->sr; priv->sr = 0; /* Then return the actual received byte */ return (int)(getreg32(SAM_DBGU_RHR) & 0xff); } /**************************************************************************** * Name: dbgu_rxint * * Description: * Call to enable or disable RXRDY interrupts * ****************************************************************************/ static void dbgu_rxint(struct uart_dev_s *dev, bool enable) { if (enable) { /* Receive an interrupt when their is anything in the Rx data register * (or an Rx timeout occurs). */ #ifndef CONFIG_SUPPRESS_SERIAL_INTS putreg32(DBGU_INT_RXRDY, SAM_DBGU_IER); #endif } else { putreg32(DBGU_INT_RXRDY, SAM_DBGU_IDR); } } /**************************************************************************** * Name: dbgu_rxavailable * * Description: * Return true if the receive holding register is not empty * ****************************************************************************/ static bool dbgu_rxavailable(struct uart_dev_s *dev) { return ((getreg32(SAM_DBGU_SR) & DBGU_INT_RXRDY) != 0); } /**************************************************************************** * Name: dbgu_send * * Description: * This method will send one byte on the DBGU/DBGU * ****************************************************************************/ static void dbgu_send(struct uart_dev_s *dev, int ch) { putreg32((uint32_t)ch, SAM_DBGU_THR); } /**************************************************************************** * Name: dbgu_txint * * Description: * Call to enable or disable TX interrupts * ****************************************************************************/ static void dbgu_txint(struct uart_dev_s *dev, bool enable) { irqstate_t flags; flags = enter_critical_section(); if (enable) { /* Set to receive an interrupt when the TX holding register register * is empty */ #ifndef CONFIG_SUPPRESS_SERIAL_INTS putreg32(DBGU_INT_TXRDY, SAM_DBGU_IER); /* Fake a TX interrupt here by just calling uart_xmitchars() with * interrupts disabled (note this may recurse). */ uart_xmitchars(dev); #endif } else { /* Disable the TX interrupt */ putreg32(DBGU_INT_TXRDY, SAM_DBGU_IDR); } leave_critical_section(flags); } /**************************************************************************** * Name: dbgu_txready * * Description: * Return true if the transmit holding register is empty (TXRDY) * ****************************************************************************/ static bool dbgu_txready(struct uart_dev_s *dev) { return ((getreg32(SAM_DBGU_SR) & DBGU_INT_TXRDY) != 0); } /**************************************************************************** * Name: dbgu_txempty * * Description: * Return true if the transmit holding and shift registers are empty * ****************************************************************************/ static bool dbgu_txempty(struct uart_dev_s *dev) { return ((getreg32(SAM_DBGU_SR) & DBGU_INT_TXEMPTY) != 0); } /**************************************************************************** * Name: sam_dbgu_devinitialize * * Description: * Performs the low level DBGU initialization early in debug so that the * DBGU console will be available during bootup. This must be called * before getreg32it. * ****************************************************************************/ void sam_dbgu_devinitialize(void) { /* Disable all DBGU interrupts */ putreg32(DBGU_INT_ALLINTS, SAM_DBGU_IDR); #ifdef CONFIG_SAMA5_DBGU_CONSOLE /* Configuration the DBGU as the console */ g_dbgu_port.isconsole = true; dbgu_configure(); #endif } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: sam_dbgu_register * * Description: * Register DBBU console and serial port. This assumes that * sam_dbgu_initialize() was called previously. * ****************************************************************************/ void sam_dbgu_register(void) { /* Register the console */ #ifdef CONFIG_SAMA5_DBGU_CONSOLE uart_register("/dev/console", &g_dbgu_port); #endif /* Register the DBGU serial device */ uart_register("/dev/ttyDBGU", &g_dbgu_port); } #endif /* USE_SERIALDRIVER */ /**************************************************************************** * Name: sam_dbgu_initialize * * Description: * Performs the low level DBGU initialization early in debug so that the * DBGU console will be available during bootup. This must be called * before getreg32it. * ****************************************************************************/ void sam_dbgu_initialize(void) { /* Initialize DBGU pins */ sam_configpio(PIO_DBGU_DRXD); sam_configpio(PIO_DBGU_DTXD); #if defined(USE_SERIALDRIVER) /* Initialize the DBGU device driver */ sam_dbgu_devinitialize(); #elif defined(CONFIG_SAMA5_DBGU_CONSOLE) sam_dbgu_configure(); #endif } #endif /* CONFIG_SAMA5_DBGU */