/* SPDX-License-Identifier: BSD-2-Clause */
/*
* Copyright (c) 2017 embedded brains GmbH. All rights reserved.
*
* 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 <sys/param.h>
#include <rtems/bspIo.h>
#include <rtems/console.h>
#include <rtems/sysinit.h>
#include <rtems/termiostypes.h>
#include <bsp.h>
#include <bsp/fdt.h>
#include <bsp/irq.h>
#include <arm/freescale/imx/imx_ccmvar.h>
#include <arm/freescale/imx/imx_uartreg.h>
#include <libfdt.h>
#define IMX_UART_TX_FIFO_LEVEL 16
typedef struct {
rtems_termios_device_context base;
volatile imx_uart *regs;
#ifdef CONSOLE_USE_INTERRUPTS
rtems_vector_number irq;
int tx_in_progress;
#endif
} imx_uart_context;
static imx_uart_context imx_uart_instances[7];
static imx_uart_context *imx_uart_console = &imx_uart_instances[0];
static volatile imx_uart *imx_uart_get_regs(rtems_termios_device_context *base)
{
imx_uart_context *ctx;
ctx = (imx_uart_context *) base;
return ctx->regs;
}
static void imx_uart_write_polled(rtems_termios_device_context *base, char c)
{
volatile imx_uart *regs;
regs = imx_uart_get_regs(base);
while ((regs->usr1 & IMX_UART_USR1_TRDY) == 0) {
/* Wait */
}
regs->utxd = IMX_UART_UTXD_TX_DATA(c);
}
static int imx_uart_read_polled(rtems_termios_device_context *base)
{
volatile imx_uart *regs;
regs = imx_uart_get_regs(base);
if ((regs->usr2 & IMX_UART_USR2_RDR) != 0) {
return IMX_UART_URXD_RX_DATA_GET(regs->urxd);
} else {
return -1;
}
}
void imx_uart_console_drain(void)
{
volatile imx_uart *regs;
regs = imx_uart_get_regs(&imx_uart_console->base);
if (regs != NULL) {
while ((regs->usr2 & IMX_UART_USR2_TXFE) == 0) {
/* Wait */
}
}
}
static void imx_output_char(char c)
{
imx_uart_write_polled(&imx_uart_console->base, c);
}
static int imx_poll_char(void)
{
return imx_uart_read_polled(&imx_uart_console->base);
}
static void imx_uart_init_context(
imx_uart_context *ctx,
const char *fdt,
const char *serial
)
{
int node;
rtems_termios_device_context_initialize(&ctx->base, "UART");
node = fdt_path_offset(fdt, serial);
ctx->regs = imx_get_reg_of_node(fdt, node);
#ifdef CONSOLE_USE_INTERRUPTS
ctx->irq = imx_get_irq_of_node(fdt, node, 0);
#endif
}
static void imx_uart_probe(void)
{
const void *fdt;
int node;
int offset;
const char *console;
size_t i;
fdt = bsp_fdt_get();
node = fdt_path_offset(fdt, "/chosen");
console = fdt_getprop(fdt, node, "stdout-path", NULL);
if (console == NULL) {
console = "";
}
node = fdt_path_offset(fdt, "/aliases");
offset = fdt_first_property_offset(fdt, node);
i = 0;
while (offset >= 0 && i < RTEMS_ARRAY_SIZE(imx_uart_instances)) {
const struct fdt_property *prop;
prop = fdt_get_property_by_offset(fdt, offset, NULL);
if (prop != NULL) {
const char *name;
name = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
if (strstr(name, "serial") != NULL) {
imx_uart_context *ctx;
const char *serial;
ctx = &imx_uart_instances[i];
serial = prop->data;
if (strcmp(serial, console) == 0) {
imx_uart_console = ctx;
}
imx_uart_init_context(ctx, fdt, serial);
++i;
}
}
offset = fdt_next_property_offset(fdt, offset);
}
BSP_output_char = imx_output_char;
BSP_poll_char = imx_poll_char;
}
static void imx_output_char_init(char c)
{
imx_uart_probe();
imx_output_char(c);
}
BSP_output_char_function_type BSP_output_char = imx_output_char_init;
BSP_polling_getchar_function_type BSP_poll_char = NULL;
#ifdef CONSOLE_USE_INTERRUPTS
static void imx_uart_interrupt(void *arg)
{
rtems_termios_tty *tty;
imx_uart_context *ctx;
volatile imx_uart *regs;
uint32_t usr2;
tty = arg;
ctx = rtems_termios_get_device_context(tty);
regs = ctx->regs;
usr2 = regs->usr2;
regs->usr1 = IMX_UART_USR1_AGTIM;
while ((usr2 & IMX_UART_USR2_RDR) != 0) {
char c;
c = IMX_UART_URXD_RX_DATA_GET(regs->urxd);
rtems_termios_enqueue_raw_characters(tty, &c, 1);
usr2 = regs->usr2;
}
if (ctx->tx_in_progress > 0 && (regs->usr1 & IMX_UART_USR1_TRDY) != 0) {
rtems_termios_dequeue_characters(tty, ctx->tx_in_progress);
}
}
#endif
static bool imx_uart_set_attributes(
rtems_termios_device_context *base,
const struct termios *term
)
{
imx_uart_context *ctx;
volatile imx_uart *regs;
uint32_t ufcr;
uint32_t baud;
ctx = (imx_uart_context *) base;
regs = imx_uart_get_regs(&ctx->base);
baud = rtems_termios_baud_to_number(term->c_ospeed);
if (baud != 0) {
ufcr = regs->ufcr;
ufcr = IMX_UART_UFCR_RFDIV_SET(ufcr, 0x5);
regs->ufcr = ufcr;
regs->ubir = 15;
regs->ubmr = imx_ccm_uart_hz() / baud - 1;
}
return true;
}
static bool imx_uart_first_open(
rtems_termios_tty *tty,
rtems_termios_device_context *base,
struct termios *term,
rtems_libio_open_close_args_t *args
)
{
imx_uart_context *ctx;
volatile imx_uart *regs;
#ifdef CONSOLE_USE_INTERRUPTS
rtems_status_code sc;
uint32_t ufcr;
#endif
ctx = (imx_uart_context *) base;
regs = imx_uart_get_regs(&ctx->base);
regs->ucr1 = IMX_UART_UCR1_UARTEN;
regs->ucr2 = IMX_UART_UCR2_IRTS | IMX_UART_UCR2_WS | IMX_UART_UCR2_RXEN
| IMX_UART_UCR2_TXEN | IMX_UART_UCR2_SRST;
regs->ucr3 |= IMX_UART_UCR3_ADNIMP | IMX_UART_UCR3_RXDMUXSEL;
rtems_termios_set_initial_baud(tty, 115200);
imx_uart_set_attributes(base, term);
#ifdef CONSOLE_USE_INTERRUPTS
ufcr = regs->ufcr;
ufcr = IMX_UART_UFCR_RXTL_SET(ufcr, 16);
ufcr = IMX_UART_UFCR_TXTL_SET(ufcr, IMX_UART_TX_FIFO_LEVEL);
regs->ufcr = ufcr;
regs->ucr1 |= IMX_UART_UCR1_RRDYEN;
regs->ucr2 |= IMX_UART_UCR2_ATEN;
sc = rtems_interrupt_handler_install(
ctx->irq,
"UART",
RTEMS_INTERRUPT_SHARED,
imx_uart_interrupt,
tty
);
if (sc != RTEMS_SUCCESSFUL) {
return false;
}
#endif
return true;
}
static void imx_uart_last_close(
rtems_termios_tty *tty,
rtems_termios_device_context *base,
rtems_libio_open_close_args_t *args
)
{
#ifdef CONSOLE_USE_INTERRUPTS
imx_uart_context *ctx;
ctx = (imx_uart_context *) base;
rtems_interrupt_handler_remove(ctx->irq, imx_uart_interrupt, tty);
#endif
}
static void imx_uart_write(
rtems_termios_device_context *base,
const char *buf,
size_t len
)
{
#ifdef CONSOLE_USE_INTERRUPTS
imx_uart_context *ctx;
volatile imx_uart *regs;
int n;
uint32_t ucr1;
ctx = (imx_uart_context *) base;
regs = imx_uart_get_regs(&ctx->base);
ucr1 = regs->ucr1;
if (len > 0) {
int i;
n = (int) MIN(len, IMX_UART_TX_FIFO_LEVEL);
ucr1 |= IMX_UART_UCR1_TRDYEN;
for (i = 0; i < n; ++i) {
regs->utxd = IMX_UART_UTXD_TX_DATA(buf[i]);
}
} else {
n = 0;
ucr1 &= ~IMX_UART_UCR1_TRDYEN;
}
regs->ucr1 = ucr1;
ctx->tx_in_progress = n;
#else
size_t i;
for (i = 0; i < len; ++i) {
imx_uart_write_polled(base, buf[i]);
}
#endif
}
static const rtems_termios_device_handler imx_uart_handler = {
.first_open = imx_uart_first_open,
.last_close = imx_uart_last_close,
.write = imx_uart_write,
.set_attributes = imx_uart_set_attributes,
#ifdef CONSOLE_USE_INTERRUPTS
.mode = TERMIOS_IRQ_DRIVEN
#else
.poll_read = imx_uart_read_polled,
.mode = TERMIOS_POLLED
#endif
};
rtems_status_code console_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
char path[] = "/dev/ttyS?";
size_t i;
rtems_termios_initialize();
for (i = 0; i < RTEMS_ARRAY_SIZE(imx_uart_instances); ++i) {
imx_uart_context *ctx;
ctx = &imx_uart_instances[i];
path[sizeof(path) - 2] = (char) ('0' + i);
rtems_termios_device_install(
path,
&imx_uart_handler,
NULL,
&ctx->base
);
if (ctx == imx_uart_console) {
link(path, CONSOLE_DEVICE_NAME);
}
}
return RTEMS_SUCCESSFUL;
}
RTEMS_SYSINIT_ITEM(
imx_uart_probe,
RTEMS_SYSINIT_BSP_START,
RTEMS_SYSINIT_ORDER_LAST_BUT_5
);