/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (C) 2013, 2017 embedded brains GmbH
*
* 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.
*
* 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.
*/
#include <dev/serial/zynq-uart.h>
#include <dev/serial/zynq-uart-regs.h>
#include <bsp/irq.h>
#include <bspopts.h>
#ifdef ZYNQ_CONSOLE_USE_INTERRUPTS
static void zynq_uart_interrupt(void *arg)
{
rtems_termios_tty *tty = arg;
zynq_uart_context *ctx = rtems_termios_get_device_context(tty);
volatile zynq_uart *regs = ctx->regs;
if ((regs->irq_sts & ZYNQ_UART_RTRIG) != 0) {
char buf[32];
int c = 0;
regs->irq_sts = ZYNQ_UART_RTRIG;
while (c < sizeof(buf) &&
(regs->channel_sts & ZYNQ_UART_CHANNEL_STS_REMPTY) == 0) {
buf[c++] = (char) ZYNQ_UART_TX_RX_FIFO_FIFO_GET(regs->tx_rx_fifo);
}
rtems_termios_enqueue_raw_characters(tty, buf, c);
}
if (ctx->transmitting) {
int sent = ctx->tx_queued;
regs->irq_dis = ZYNQ_UART_TEMPTY;
ctx->transmitting = false;
ctx->tx_queued = 0;
rtems_termios_dequeue_characters(tty, sent);
}
}
#endif
static bool zynq_uart_first_open(
rtems_termios_tty *tty,
rtems_termios_device_context *base,
struct termios *term,
rtems_libio_open_close_args_t *args
)
{
#ifdef ZYNQ_CONSOLE_USE_INTERRUPTS
zynq_uart_context *ctx = (zynq_uart_context *) base;
volatile zynq_uart *regs = ctx->regs;
rtems_status_code sc;
#endif
rtems_termios_set_initial_baud(tty, ZYNQ_UART_DEFAULT_BAUD);
zynq_uart_initialize(base);
#ifdef ZYNQ_CONSOLE_USE_INTERRUPTS
regs->rx_fifo_trg_lvl = 1;
regs->irq_dis = 0xffffffff;
regs->irq_sts = 0xffffffff;
regs->irq_en = ZYNQ_UART_RTRIG;
sc = rtems_interrupt_handler_install(
ctx->irq,
"UART",
RTEMS_INTERRUPT_SHARED,
zynq_uart_interrupt,
tty
);
if (sc != RTEMS_SUCCESSFUL) {
return false;
}
#endif
return true;
}
#ifdef ZYNQ_CONSOLE_USE_INTERRUPTS
static void zynq_uart_last_close(
rtems_termios_tty *tty,
rtems_termios_device_context *base,
rtems_libio_open_close_args_t *args
)
{
zynq_uart_context *ctx = (zynq_uart_context *) base;
rtems_interrupt_handler_remove(ctx->irq, zynq_uart_interrupt, tty);
}
#endif
static void zynq_uart_write_support(
rtems_termios_device_context *base,
const char *buf,
size_t len
)
{
#ifdef ZYNQ_CONSOLE_USE_INTERRUPTS
zynq_uart_context *ctx = (zynq_uart_context *) base;
volatile zynq_uart *regs = ctx->regs;
regs->irq_dis = ZYNQ_UART_TEMPTY;
if (len > 0) {
const char *p = &buf[0];
regs->irq_sts = ZYNQ_UART_TEMPTY;
while (((regs->channel_sts & ZYNQ_UART_CHANNEL_STS_TNFUL) == 0) &&
len > 0) {
regs->tx_rx_fifo = ZYNQ_UART_TX_RX_FIFO_FIFO(*p);
++p;
++ctx->tx_queued;
--len;
}
ctx->transmitting = true;
regs->irq_en = ZYNQ_UART_TEMPTY;
}
#else
ssize_t i;
for (i = 0; i < len; ++i) {
zynq_uart_write_polled(base, buf[i]);
}
#endif
}
static bool zynq_uart_set_attributes(
rtems_termios_device_context *context,
const struct termios *term
)
{
zynq_uart_context *ctx = (zynq_uart_context *) context;
volatile zynq_uart *regs = ctx->regs;
int32_t baud;
uint32_t brgr = 0;
uint32_t bauddiv = 0;
uint32_t mode = 0;
int rc;
/*
* Determine the baud rate
*/
baud = rtems_termios_baud_to_number(term->c_ospeed);
if (baud > 0) {
rc = zynq_cal_baud_rate(baud, &brgr, &bauddiv, regs->mode);
if (rc != 0)
return rc;
}
/*
* Configure the mode register
*/
mode = regs->mode & ZYNQ_UART_MODE_CLKS;
mode |= ZYNQ_UART_MODE_CHMODE(ZYNQ_UART_MODE_CHMODE_NORMAL);
/*
* Parity
*/
mode |= ZYNQ_UART_MODE_PAR(ZYNQ_UART_MODE_PAR_NONE);
if (term->c_cflag & PARENB) {
if (!(term->c_cflag & PARODD)) {
mode |= ZYNQ_UART_MODE_PAR(ZYNQ_UART_MODE_PAR_ODD);
} else {
mode |= ZYNQ_UART_MODE_PAR(ZYNQ_UART_MODE_PAR_EVEN);
}
}
/*
* Character Size
*/
switch (term->c_cflag & CSIZE)
{
case CS5:
return false;
case CS6:
mode |= ZYNQ_UART_MODE_CHRL(ZYNQ_UART_MODE_CHRL_6);
break;
case CS7:
mode |= ZYNQ_UART_MODE_CHRL(ZYNQ_UART_MODE_CHRL_7);
break;
case CS8:
default:
mode |= ZYNQ_UART_MODE_CHRL(ZYNQ_UART_MODE_CHRL_8);
break;
}
/*
* Stop Bits
*/
if (term->c_cflag & CSTOPB) {
/* 2 stop bits */
mode |= ZYNQ_UART_MODE_NBSTOP(ZYNQ_UART_MODE_NBSTOP_STOP_2);
} else {
/* 1 stop bit */
mode |= ZYNQ_UART_MODE_NBSTOP(ZYNQ_UART_MODE_NBSTOP_STOP_1);
}
/*
* Wait for any data in the TXFIFO to be sent then wait while the
* transmiter is active.
*/
while ((regs->channel_sts & ZYNQ_UART_CHANNEL_STS_TEMPTY) == 0 ||
(regs->channel_sts & ZYNQ_UART_CHANNEL_STS_TACTIVE) != 0) {
/* Wait */
}
regs->control = ZYNQ_UART_CONTROL_RXDIS | ZYNQ_UART_CONTROL_TXDIS;
/* Ignore baud rate of B0. There are no modem control lines to de-assert */
if (baud > 0) {
regs->baud_rate_gen = ZYNQ_UART_BAUD_RATE_GEN_CD(brgr);
regs->baud_rate_div = ZYNQ_UART_BAUD_RATE_DIV_BDIV(bauddiv);
}
regs->control = ZYNQ_UART_CONTROL_RXRES | ZYNQ_UART_CONTROL_TXRES;
regs->mode = mode;
regs->irq_sts = 0xffffffff;
regs->control = ZYNQ_UART_CONTROL_RXEN | ZYNQ_UART_CONTROL_TXEN;
return true;
}
const rtems_termios_device_handler zynq_uart_handler = {
.first_open = zynq_uart_first_open,
.set_attributes = zynq_uart_set_attributes,
.write = zynq_uart_write_support,
#ifdef ZYNQ_CONSOLE_USE_INTERRUPTS
.last_close = zynq_uart_last_close,
.mode = TERMIOS_IRQ_DRIVEN
#else
.poll_read = zynq_uart_read_polled,
.mode = TERMIOS_POLLED
#endif
};