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bsp/lm3s69xx: Use interrupts for UART receive

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This makes continuous UART polling unnecessary.
This commit is contained in:
Eugeniy Meshcheryakov
2013-05-06 00:02:07 +02:00
committed by Sebastian Huber
parent 847e2cac7c
commit 9bc1913e09
1 changed files with 47 additions and 12 deletions
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59
c/src/lib/libbsp/arm/lm3s69xx/console/uart.c
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@@ -19,6 +19,10 @@
#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)
{
@@ -43,8 +47,36 @@ static uint32_t get_baud_div(uint32_t baud)
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);
@@ -58,6 +90,10 @@ static void initialize(int minor)
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)
@@ -65,27 +101,26 @@ 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)
{
return 0;
}
static int read_polled(int minor)
{
volatile lm3s69xx_uart *uart = get_uart_regs(minor);
uart->im = 0;
if ((uart->fr & UARTFR_RXFE) != 0) {
return -1;
} else {
return UARTDR_DATA(uart->dr);
}
return 0;
}
static void write_polled(int minor, char c)
@@ -123,10 +158,10 @@ const console_fns lm3s69xx_uart_fns = {
.deviceProbe = libchip_serial_default_probe,
.deviceFirstOpen = first_open,
.deviceLastClose = last_close,
.deviceRead = read_polled,
.deviceRead = NULL,
.deviceWrite = write_support_polled,
.deviceInitialize = initialize,
.deviceWritePolled = write_polled,
.deviceSetAttributes = set_attribues,
.deviceOutputUsesInterrupts = false
.deviceOutputUsesInterrupts = TERMIOS_POLLED
};