/****************************************************************************
* arch/arm/src/efm32/efm32_leserial.c
*
* Copyright (C) 2024 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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/irq.h>
#include <nuttx/arch.h>
#include <nuttx/serial/serial.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "up_internal.h"
#include "chip/efm32_leuart.h"
#include "efm32_config.h"
#include "efm32_lowputc.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Some sanity checks *******************************************************/
/* Is there at least one UART enabled and configured as a RS-232 device? */
#ifndef HAVE_LEUART_DEVICE
# warning "No LEUARTs enabled"
#endif
/* If we are not using the serial driver for the console, then we still must
* provide some minimal implementation of up_putc.
*/
#ifdef USE_SERIALDRIVER
/* Which LEUART with be ttyLE0/console and which ttyLE1? The console will always
* be ttyLE0. If there is no console then will use the lowest numbered LEUART.
*/
/* First pick the console and ttys0. This could be either LEUART0-1 */
#if defined(CONFIG_LEUART0_SERIAL_CONSOLE)
# define CONSOLE_DEV g_leuart0port /* LEUART0 is console */
# define TTYLE0_DEV g_leuart0port /* LEUART0 is ttyLE0 */
# define LEUART0_ASSIGNED 1
#elif defined(CONFIG_LEUART1_SERIAL_CONSOLE)
# define CONSOLE_DEV g_leuart1port /* LEUART1 is console */
# define TTYLE0_DEV g_leuart1port /* LEUART1 is ttyLE0 */
# define LEUART1_ASSIGNED 1
#else
# undef CONSOLE_DEV /* No console */
# if defined(CONFIG_EFM32_LEUART0)
# define TTYLE0_DEV g_leuart0port /* LEUART0 is ttyLE0 */
# define LEUART0_ASSIGNED 1
# elif defined(CONFIG_EFM32_LEUART1)
# define TTYLE0_DEV g_leuart1port /* LEUART1 is ttyLE0 */
# define LEUART1_ASSIGNED 1
# endif
#endif
/* Pick ttyLE1. This could be any of LEUART0-1, excluding the and the
* LEUART already selected for ttyLE0
*/
#if defined(CONFIG_EFM32_LEUART0) && !defined(LEUART0_ASSIGNED)
# define TTYLE1_DEV g_leuart0port /* LEUART0 is ttyLE1 */
# define LEUART0_ASSIGNED 1
#elif defined(CONFIG_EFM32_LEUART1) && !defined(LEUART1_ASSIGNED)
# define TTYLE1_DEV g_leuart1port /* LEUART1 is ttyLE1 */
# define LEUART1_ASSIGNED 1
#endif
/* TX/RX interrupts */
#define EFM32_TXERR_INTS (LEUART_IEN_TXOF)
#define EFM32_RXERR_INTS (LEUART_IEN_RXOF | LEUART_IEN_PERR | \
LEUART_IEN_FERR)
#ifdef CONFIG_DEBUG_FEATURES
# define EFM32_TX_INTS (LEUART_IEN_TXBL | EFM32_TXERR_INTS)
# define EFM32_RX_INTS (LEUART_IEN_RXDATAV | EFM32_RXERR_INTS)
#else
# define EFM32_TX_INTS LEUART_IEN_TXBL
# define EFM32_RX_INTS LEUART_IEN_RXDATAV
#endif
/****************************************************************************
* Private Types
****************************************************************************/
struct efm32_config_s
{
uintptr_t uartbase; /* Base address of UART registers */
uint32_t baud; /* Configured baud */
uint8_t irq; /* IRQ associated with this LEUART (for enable) */
uint8_t parity; /* 0=none, 1=odd, 2=even */
uint8_t bits; /* Number of bits (8 or 9) */
bool stop2; /* True: 2 stop bits */
};
struct efm32_leuart_s
{
const struct efm32_config_s *config;
uint16_t ien; /* Interrupts enabled */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static inline uint32_t efm32_serialin(struct efm32_leuart_s *priv, int offset);
static inline void efm32_serialout(struct efm32_leuart_s *priv, int offset,
uint32_t value);
static inline void efm32_setuartint(struct efm32_leuart_s *priv);
static void efm32_restoreuartint(struct efm32_leuart_s *priv, uint32_t ien);
static void efm32_disableuartint(struct efm32_leuart_s *priv, uint32_t *ien);
static int efm32_setup(struct uart_dev_s *dev);
static void efm32_shutdown(struct uart_dev_s *dev);
static int efm32_attach(struct uart_dev_s *dev);
static void efm32_detach(struct uart_dev_s *dev);
static int efm32_interrupt(int irq, void *context, FAR void *arg);
static int efm32_ioctl(struct file *filep, int cmd, unsigned long arg);
static int efm32_receive(struct uart_dev_s *dev, uint32_t *status);
static void efm32_rxint(struct uart_dev_s *dev, bool enable);
static bool efm32_rxavailable(struct uart_dev_s *dev);
static void efm32_send(struct uart_dev_s *dev, int ch);
static void efm32_txint(struct uart_dev_s *dev, bool enable);
static bool efm32_txready(struct uart_dev_s *dev);
static bool efm32_txempty(struct uart_dev_s *dev);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct uart_ops_s g_leuart_ops =
{
.setup = efm32_setup,
.shutdown = efm32_shutdown,
.attach = efm32_attach,
.detach = efm32_detach,
.ioctl = efm32_ioctl,
.receive = efm32_receive,
.rxint = efm32_rxint,
.rxavailable = efm32_rxavailable,
#ifdef CONFIG_SERIAL_IFLOWCONTROL
.rxflowcontrol = NULL,
#endif
.send = efm32_send,
.txint = efm32_txint,
.txready = efm32_txready,
.txempty = efm32_txempty,
};
/* I/O buffers */
#ifdef CONFIG_EFM32_LEUART0
static char g_leuart0rxbuffer[CONFIG_LEUART0_RXBUFSIZE];
static char g_leuart0txbuffer[CONFIG_LEUART0_TXBUFSIZE];
#endif
#ifdef CONFIG_EFM32_LEUART1
static char g_leuart1rxbuffer[CONFIG_LEUART1_RXBUFSIZE];
static char g_leuart1txbuffer[CONFIG_LEUART1_TXBUFSIZE];
#endif
/* This describes the state of the EFM32 LEUART0 port. */
#ifdef CONFIG_EFM32_LEUART0
static const struct efm32_config_s g_leuart0config =
{
.uartbase = EFM32_LEUART0_BASE,
.baud = CONFIG_LEUART0_BAUD,
.irq = EFM32_IRQ_LEUART0,
.parity = CONFIG_LEUART0_PARITY,
.bits = CONFIG_LEUART0_BITS,
.stop2 = CONFIG_LEUART0_2STOP,
};
static struct efm32_leuart_s g_leuart0priv =
{
.config = &g_leuart0config,
};
static struct uart_dev_s g_leuart0port =
{
.recv =
{
.size = CONFIG_LEUART0_RXBUFSIZE,
.buffer = g_leuart0rxbuffer,
},
.xmit =
{
.size = CONFIG_LEUART0_TXBUFSIZE,
.buffer = g_leuart0txbuffer,
},
.ops = &g_leuart_ops,
.priv = &g_leuart0priv,
};
#endif
/* This describes the state of the EFM32 LEUART1 port. */
#ifdef CONFIG_EFM32_LEUART1
static struct efm32_config_s g_leuart1config =
{
.uartbase = EFM32_LEUART1_BASE,
.baud = CONFIG_LEUART1_BAUD,
.irq = EFM32_IRQ_LEUART1,
.parity = CONFIG_LEUART1_PARITY,
.bits = CONFIG_LEUART1_BITS,
.stop2 = CONFIG_LEUART1_2STOP,
};
static struct efm32_leuart_s g_leuart1priv =
{
.config = &g_leuart1config,
};
static struct uart_dev_s g_leuart1port =
{
.recv =
{
.size = CONFIG_LEUART1_RXBUFSIZE,
.buffer = g_leuart1rxbuffer,
},
.xmit =
{
.size = CONFIG_LEUART1_TXBUFSIZE,
.buffer = g_leuart1txbuffer,
},
.ops = &g_leuart_ops,
.priv = &g_leuart1priv,
};
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: efm32_serialin
****************************************************************************/
static inline uint32_t efm32_serialin(struct efm32_leuart_s *priv, int offset)
{
return getreg32(priv->config->uartbase + offset);
}
/****************************************************************************
* Name: efm32_serialout
****************************************************************************/
static inline void efm32_serialout(struct efm32_leuart_s *priv, int offset,
uint32_t value)
{
putreg32(value, priv->config->uartbase + offset);
}
/****************************************************************************
* Name: efm32_setuartint
****************************************************************************/
static inline void efm32_setuartint(struct efm32_leuart_s *priv)
{
efm32_serialout(priv, EFM32_LEUART_IEN_OFFSET, priv->ien);
}
/****************************************************************************
* Name: efm32_restoreuartint
****************************************************************************/
static void efm32_restoreuartint(struct efm32_leuart_s *priv, uint32_t ien)
{
irqstate_t flags;
/* Re-enable/re-disable interrupts corresponding to the state of bits in ien */
flags = enter_critical_section();
priv->ien = ien;
efm32_setuartint(priv);
leave_critical_section(flags);
}
/****************************************************************************
* Name: efm32_disableuartint
****************************************************************************/
static void efm32_disableuartint(struct efm32_leuart_s *priv, uint32_t *ien)
{
irqstate_t flags;
flags = enter_critical_section();
if (ien)
{
*ien = priv->ien;
}
efm32_restoreuartint(priv, 0);
leave_critical_section(flags);
}
/****************************************************************************
* Name: efm32_setup
*
* Description:
* Configure the UART baud, bits, parity, etc. This method is called the
* first time that the serial port is opened.
*
****************************************************************************/
static int efm32_setup(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
#ifndef CONFIG_SUPPRESS_LEUART_CONFIG
const struct efm32_config_s *config = priv->config;
/* Configure the UART as an RS-232 UART */
efm32_leuartconfigure(config->uartbase, config->baud, config->parity,
config->bits, config->stop2);
#endif
/* Make sure that all interrupts are disabled */
efm32_restoreuartint(priv, 0);
return OK;
}
/****************************************************************************
* Name: efm32_shutdown
*
* Description:
* Disable the UART. This method is called when the serial
* port is closed
*
****************************************************************************/
static void efm32_shutdown(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
/* Disable interrupts */
efm32_restoreuartint(priv, 0);
/* Reset the LEUART/UART by disabling it and restoring all of the registers
* to the initial, reset value. Only the ROUTE data set by efm32_lowsetup
* is preserved.
*/
efm32_leuart_reset(priv->config->uartbase);
}
/****************************************************************************
* Name: efm32_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 efm32_attach(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
const struct efm32_config_s *config = priv->config;
int ret;
/* Attach and enable the IRQ(s). The interrupts are (probably) still
* disabled in the C2 register.
*/
ret = irq_attach(config->irq, efm32_interrupt, dev);
if (ret >= 0)
{
up_enable_irq(config->irq);
}
return ret;
}
/****************************************************************************
* Name: efm32_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 efm32_detach(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
const struct efm32_config_s *config = priv->config;
/* Disable interrupts */
efm32_restoreuartint(priv, 0);
up_disable_irq(config->irq);
/* Detach from the interrupt(s) */
irq_detach(config->irq);
}
/****************************************************************************
* Name: efm32_interrupt
*
* Description:
* This is the common UART RX interrupt handler.
*
****************************************************************************/
static int efm32_interrupt(int irq, void *context, FAR void *arg)
{
struct uart_dev_s *dev = (struct uart_dev_s *)arg;
struct efm32_leuart_s *priv;
uint32_t intflags;
DEBUGASSERT(dev != NULL && dev->priv != NULL);
priv = (struct efm32_leuart_s *)dev->priv;
/* Read the interrupt flags register */
intflags = efm32_serialin(priv, EFM32_LEUART_IF_OFFSET);
/* Clear pending interrupts by writing to the interrupt flag clear
* register.
*/
efm32_serialout(priv, EFM32_LEUART_IFC_OFFSET, intflags);
/* Check if the receive data is available is full (RXDATAV). */
if ((intflags & LEUART_IEN_RXDATAV) != 0)
{
/* Process incoming bytes */
uart_recvchars(dev);
}
/* Check if the transmit data buffer became empty */
if ((intflags & LEUART_IEN_TXBL) != 0)
{
/* Process outgoing bytes */
uart_xmitchars(dev);
}
#ifdef CONFIG_DEBUG_FEATURES
/* Check for receive errors */
if ((intflags & EFM32_RXERR_INTS) != 0)
{
/* RXOF - RX Overflow Interrupt Enable
* RXUF - RX Underflow Interrupt Enable
* TXUF - TX Underflow Interrupt Enable
* PERR - Parity Error Interrupt Enable
* FERR - Framing Error Interrupt Enable
*/
_err("RX ERROR: %08x\n", intflags);
}
/* Check for transmit errors */
if ((intflags & EFM32_TXERR_INTS) != 0)
{
/* TXOF - TX Overflow Interrupt Enable */
_err("RX ERROR: %08x\n", intflags);
}
#endif
return OK;
}
/****************************************************************************
* Name: efm32_ioctl
*
* Description:
* All ioctl calls will be routed through this method
*
****************************************************************************/
static int efm32_ioctl(struct file *filep, int cmd, unsigned long arg)
{
#if 0 /* Reserved for future growth */
struct inode *inode;
struct uart_dev_s *dev;
struct efm32_leuart_s *priv;
int ret = OK;
DEBUGASSERT(filep, filep->f_inode);
inode = filep->f_inode;
dev = inode->i_private;
DEBUGASSERT(dev, dev->priv);
priv = (struct efm32_leuart_s *)dev->priv;
switch (cmd)
{
case xxx: /* Add commands here */
break;
default:
ret = -ENOTTY;
break;
}
return ret;
#else
return -ENOTTY;
#endif
}
/****************************************************************************
* Name: efm32_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 efm32_receive(struct uart_dev_s *dev, uint32_t *status)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
uint32_t rxdatax;
/* Get error status information:
*
* FERR Data Framing Error
* PERR Data Parity Error
*/
rxdatax = efm32_serialin(priv, EFM32_LEUART_RXDATAX_OFFSET);
/* Return status information */
if (status)
{
*status = rxdatax;
}
/* Then return the actual received byte. */
return (int)(rxdatax & _LEUART_RXDATAX_RXDATA_MASK);
}
/****************************************************************************
* Name: efm32_rxint
*
* Description:
* Call to enable or disable RX interrupts
*
****************************************************************************/
static void efm32_rxint(struct uart_dev_s *dev, bool enable)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
irqstate_t flags;
flags = enter_critical_section();
if (enable)
{
/* Receive an interrupt when their is anything in the Rx data register (or an Rx
* timeout occurs).
*/
#ifndef CONFIG_SUPPRESS_SERIAL_INTS
priv->ien |= EFM32_RX_INTS;
efm32_setuartint(priv);
#endif
}
else
{
priv->ien &= ~EFM32_RX_INTS;
efm32_setuartint(priv);
}
leave_critical_section(flags);
}
/****************************************************************************
* Name: efm32_rxavailable
*
* Description:
* Return true if the receive register is not empty
*
****************************************************************************/
static bool efm32_rxavailable(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
/* Return true if the receive data is available (RXDATAV). */
return (efm32_serialin(priv, EFM32_LEUART_STATUS_OFFSET) & LEUART_STATUS_RXDATAV) != 0;
}
/****************************************************************************
* Name: efm32_send
*
* Description:
* This method will send one byte on the UART.
*
****************************************************************************/
static void efm32_send(struct uart_dev_s *dev, int ch)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
efm32_serialout(priv, EFM32_LEUART_TXDATA_OFFSET, (uint32_t)ch);
}
/****************************************************************************
* Name: efm32_txint
*
* Description:
* Call to enable or disable TX interrupts
*
****************************************************************************/
static void efm32_txint(struct uart_dev_s *dev, bool enable)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
irqstate_t flags;
flags = enter_critical_section();
if (enable)
{
/* Enable the TX interrupt */
#ifndef CONFIG_SUPPRESS_SERIAL_INTS
priv->ien |= EFM32_TX_INTS;
efm32_setuartint(priv);
/* 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 */
priv->ien &= ~EFM32_TX_INTS;
efm32_setuartint(priv);
}
leave_critical_section(flags);
}
/****************************************************************************
* Name: efm32_txready
*
* Description:
* Return true if the transmit data register is not full
*
****************************************************************************/
static bool efm32_txready(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
/* The TX Buffer Level (TXBL) status bit indicates the level of the
* transmit buffer. Set when the transmit buffer is empty, and cleared
* when it is full.
*/
return (efm32_serialin(priv, EFM32_LEUART_STATUS_OFFSET) & LEUART_STATUS_TXBL) != 0;
}
/****************************************************************************
* Name: efm32_txempty
*
* Description:
* Return true if the transmit data register is empty
*
****************************************************************************/
static bool efm32_txempty(struct uart_dev_s *dev)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)dev->priv;
/* TX Complete (TXC) is set when a transmission has completed and no more
* data is available in the transmit buffer.
*/
return (efm32_serialin(priv, EFM32_LEUART_STATUS_OFFSET) & LEUART_STATUS_TXC) != 0;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: up_earlyserialinit
*
* 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. NOTE: This function depends on GPIO pin
* configuration performed in efm32_consoleinit() and main clock iniialization
* performed in efm32_clkinitialize().
*
****************************************************************************/
void up_earlyserialinit(void)
{
/* Disable interrupts from all UARTS. The console is enabled in
* pic32mx_consoleinit()
*/
efm32_restoreuartint(TTYLE0_DEV.priv, 0);
#ifdef TTYLE1_DEV
efm32_restoreuartint(TTYLE1_DEV.priv, 0);
#endif
/* Configuration whichever one is the console */
#ifdef CONSOLE_DEV
CONSOLE_DEV.isconsole = true;
efm32_setup(&CONSOLE_DEV);
#endif
}
/****************************************************************************
* Name: up_serialinit
*
* Description:
* Register serial console and serial ports. This assumes that
* up_earlyserialinit was called previously.
*
****************************************************************************/
void up_serialinit(void)
{
/* Register the console */
#ifdef CONSOLE_DEV
(void)uart_register("/dev/console", &CONSOLE_DEV);
#endif
/* Register all UARTs */
(void)uart_register("/dev/ttyLE0", &TTYLE0_DEV);
#ifdef TTYLE1_DEV
(void)uart_register("/dev/ttyLE1", &TTYLE1_DEV);
#endif
}
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug writes
*
****************************************************************************/
#ifdef HAVE_LEUART_CONSOLE
int up_putc(int ch)
{
struct efm32_leuart_s *priv = (struct efm32_leuart_s *)CONSOLE_DEV.priv;
uint32_t ien;
efm32_disableuartint(priv, &ien);
/* Check for LF */
if (ch == '\n')
{
/* Add CR */
efm32_lowputc('\r');
}
efm32_lowputc(ch);
efm32_restoreuartint(priv, ien);
return ch;
}
#endif
#else /* USE_SERIALDRIVER */
/****************************************************************************
* Name: up_putc
*
* Description:
* Provide priority, low-level access to support OS debug writes
*
****************************************************************************/
#ifdef HAVE_LEUART_CONSOLE
int up_putc(int ch)
{
/* Check for LF */
if (ch == '\n')
{
/* Add CR */
efm32_lowputc('\r');
}
efm32_lowputc(ch);
return ch;
}
#endif
#endif /* USE_SERIALDRIVER */