/*
* Copyright © 2013 Eugeniy Meshcheryakov <eugen@debian.org>
*
* Copyright (c) 2011 Sebastian Huber. All rights reserved.
*
* embedded brains GmbH
* Obere Lagerstr. 30
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#include <bspopts.h>
#include <bsp/uart.h>
#include <libchip/sersupp.h>
#include <bsp/syscon.h>
#include <bsp/lm3s69xx.h>
#include <rtems/irq-extension.h>
#include <assert.h>
#define LM3S69XX_UART_FIFO_DEPTH 16
static volatile lm3s69xx_uart *get_uart_regs(int minor)
{
console_tbl *ct = Console_Port_Tbl [minor];
return (lm3s69xx_uart *) ct->ulCtrlPort1;
}
static unsigned int get_uart_number(int minor)
{
console_tbl *ct = Console_Port_Tbl [minor];
return (unsigned int)ct->pDeviceParams;
}
/*
* Returns both integer and fractional parts as one number.
*/
static uint32_t get_baud_div(uint32_t baud)
{
uint32_t clock4 = LM3S69XX_SYSTEM_CLOCK * 4;
return (clock4 + baud - 1) / baud;
}
static void irq_handler(void *arg)
{
int minor = (int)arg;
console_data *cd = &Console_Port_Data [minor];
volatile lm3s69xx_uart *uart = get_uart_regs(minor);
do {
char buf[LM3S69XX_UART_FIFO_DEPTH];
int i = 0;
uint32_t status = uart->fr;
while (((status & UARTFR_RXFE) == 0) && (i < LM3S69XX_UART_FIFO_DEPTH)) {
uint32_t d = uart->dr;
if ((d & UARTDR_ERROR_MSK) == 0) {
buf[i] = UARTDR_DATA_GET(d);
i++;
}
status = uart->fr;
}
if (i > 0)
rtems_termios_enqueue_raw_characters(cd->termios_data, buf, i);
} while (uart->mis != 0);
}
static void initialize(int minor)
{
const console_tbl *ct = Console_Port_Tbl[minor];
volatile lm3s69xx_uart *uart = get_uart_regs(minor);
unsigned int num = get_uart_number(minor);
lm3s69xx_syscon_enable_uart_clock(num, true);
uart->ctl = 0;
uint32_t brd = get_baud_div(LM3S69XX_UART_BAUD);
uart->ibrd = brd / 64;
uart->fbrd = brd % 64;
uart->lcrh = UARTLCRH_WLEN(0x3) | UARTLCRH_FEN;
uart->ctl = UARTCTL_RXE | UARTCTL_TXE | UARTCTL_UARTEN;
int rv = rtems_interrupt_handler_install(ct->ulIntVector, "UART",
RTEMS_INTERRUPT_UNIQUE, irq_handler, (void *)minor);
assert(rv == RTEMS_SUCCESSFUL);
}
static int first_open(int major, int minor, void *arg)
{
rtems_libio_open_close_args_t *oc = (rtems_libio_open_close_args_t *) arg;
struct rtems_termios_tty *tty = (struct rtems_termios_tty *) oc->iop->data1;
console_data *cd = &Console_Port_Data [minor];
volatile lm3s69xx_uart *uart = get_uart_regs(minor);
cd->termios_data = tty;
rtems_termios_set_initial_baud(tty, LM3S69XX_UART_BAUD);
/* Drain the RX FIFO. */
while ((uart->fr & UARTFR_RXFE) == 0)
(void)uart->dr;
uart->im = UARTI_RX | UARTI_RT;
return 0;
}
static int last_close(int major, int minor, void *arg)
{
volatile lm3s69xx_uart *uart = get_uart_regs(minor);
uart->im = 0;
return 0;
}
static void write_polled(int minor, char c)
{
volatile lm3s69xx_uart *uart = get_uart_regs(minor);
while ((uart->fr & UARTFR_TXFF) != 0) {
/* Wait */
}
uart->dr = UARTDR_DATA(c);
}
static ssize_t write_support_polled(
int minor,
const char *s,
size_t n
)
{
ssize_t i = 0;
for (i = 0; i < n; ++i) {
write_polled(minor, s [i]);
}
return n;
}
static int set_attribues(int minor, const struct termios *term)
{
return -1;
}
const console_fns lm3s69xx_uart_fns = {
.deviceProbe = libchip_serial_default_probe,
.deviceFirstOpen = first_open,
.deviceLastClose = last_close,
.deviceRead = NULL,
.deviceWrite = write_support_polled,
.deviceInitialize = initialize,
.deviceWritePolled = write_polled,
.deviceSetAttributes = set_attribues,
.deviceOutputUsesInterrupts = false
};