/*
* This file is free software: you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This file is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program. If not, see .
*
* Code by Andrew Tridgell and Siddharth Bharat Purohit
*/
#include
#if CONFIG_HAL_BOARD == HAL_BOARD_CHIBIOS && !defined(HAL_NO_UARTDRIVER)
#include "UARTDriver.h"
#include "GPIO.h"
#include
#include "shared_dma.h"
#include
#include
#include
#include "Scheduler.h"
#include "hwdef/common/stm32_util.h"
extern const AP_HAL::HAL& hal;
using namespace ChibiOS;
#ifdef HAL_USB_VENDOR_ID
// USB has been configured in hwdef.dat
#define HAVE_USB_SERIAL
#endif
#if HAL_WITH_IO_MCU
extern ChibiOS::UARTDriver uart_io;
#endif
const UARTDriver::SerialDef UARTDriver::_serial_tab[] = { HAL_UART_DEVICE_LIST };
// handle for UART handling thread
thread_t* volatile UARTDriver::uart_rx_thread_ctx;
// table to find UARTDrivers from serial number, used for event handling
UARTDriver *UARTDriver::uart_drivers[UART_MAX_DRIVERS];
// event used to wake up waiting thread. This event number is for
// caller threads
static const eventmask_t EVT_DATA = EVENT_MASK(10);
// event for parity error
static const eventmask_t EVT_PARITY = EVENT_MASK(11);
// event for transmit end for half-duplex
static const eventmask_t EVT_TRANSMIT_END = EVENT_MASK(12);
// events for dma tx, thread per UART so can be from 0
static const eventmask_t EVT_TRANSMIT_DMA_START = EVENT_MASK(0);
static const eventmask_t EVT_TRANSMIT_DMA_COMPLETE = EVENT_MASK(1);
static const eventmask_t EVT_TRANSMIT_DATA_READY = EVENT_MASK(2);
static const eventmask_t EVT_TRANSMIT_UNBUFFERED = EVENT_MASK(3);
#ifndef HAL_UART_MIN_TX_SIZE
#define HAL_UART_MIN_TX_SIZE 512
#endif
#ifndef HAL_UART_MIN_RX_SIZE
#define HAL_UART_MIN_RX_SIZE 512
#endif
#ifndef HAL_UART_STACK_SIZE
#define HAL_UART_STACK_SIZE 320
#endif
#ifndef HAL_UART_RX_STACK_SIZE
#define HAL_UART_RX_STACK_SIZE 768
#endif
// threshold for disabling TX DMA due to contention
#if defined(USART_CR1_FIFOEN)
#define CONTENTION_BAUD_THRESHOLD 460800
#else
#define CONTENTION_BAUD_THRESHOLD 115200
#endif
UARTDriver::UARTDriver(uint8_t _serial_num) :
serial_num(_serial_num),
sdef(_serial_tab[_serial_num]),
_baudrate(57600)
{
osalDbgAssert(serial_num < UART_MAX_DRIVERS, "too many UART drivers");
uart_drivers[serial_num] = this;
}
/*
thread for handling UART send/receive
We use events indexed by serial_num to trigger a more rapid send for
unbuffered_write uarts, and run at 1kHz for general UART handling
*/
#pragma GCC diagnostic push
#pragma GCC diagnostic error "-Wframe-larger-than=128"
void UARTDriver::uart_thread()
{
uint32_t last_thread_run_us = 0; // last time we did a 1kHz run of this uart
while (uart_thread_ctx == nullptr) {
hal.scheduler->delay_microseconds(1000);
}
while (true) {
eventmask_t mask = chEvtWaitAnyTimeout(EVT_TRANSMIT_DATA_READY | EVT_TRANSMIT_END | EVT_TRANSMIT_UNBUFFERED, chTimeMS2I(1));
uint32_t now = AP_HAL::micros();
bool need_tick = false;
if (now - last_thread_run_us >= 1000) {
// run the timer tick if it's been more than 1ms since we last run
need_tick = true;
last_thread_run_us = now;
}
// change the thread priority if requested - if unbuffered it should only have higher priority than the owner so that
// handoff occurs immediately
if (mask & EVT_TRANSMIT_UNBUFFERED) {
chThdSetPriority(unbuffered_writes ? MIN(_uart_owner_thd->realprio + 1, APM_UART_UNBUFFERED_PRIORITY) : APM_UART_PRIORITY);
}
#ifndef HAL_UART_NODMA
osalDbgAssert(!dma_handle || !dma_handle->is_locked(), "DMA handle is already locked");
#endif
// send more data
if (_tx_initialised && ((mask & EVT_TRANSMIT_DATA_READY) || need_tick || (hd_tx_active && (mask & EVT_TRANSMIT_END)))) {
_tx_timer_tick();
}
}
}
#pragma GCC diagnostic pop
/*
thread for handling UART receive
We use events indexed by serial_num to trigger a more rapid send for
unbuffered_write uarts, and run at 1kHz for general UART handling
*/
void UARTDriver::uart_rx_thread(void* arg)
{
while (uart_rx_thread_ctx == nullptr) {
hal.scheduler->delay_microseconds(1000);
}
while (true) {
hal.scheduler->delay_microseconds(1000);
for (uint8_t i=0; i_rx_initialised) {
uart_drivers[i]->_rx_timer_tick();
}
}
}
}
/*
initialise UART RX thread
*/
void UARTDriver::thread_rx_init(void)
{
if (uart_rx_thread_ctx == nullptr) {
uart_rx_thread_ctx = thread_create_alloc(THD_WORKING_AREA_SIZE(HAL_UART_RX_STACK_SIZE),
"UART_RX",
APM_UART_PRIORITY,
uart_rx_thread,
nullptr);
if (uart_rx_thread_ctx == nullptr) {
AP_HAL::panic("Could not create UART RX thread\n");
}
}
}
/*
initialise UART TX_thread
*/
void UARTDriver::thread_init(void)
{
if (uart_thread_ctx == nullptr) {
hal.util->snprintf(uart_thread_name, sizeof(uart_thread_name), sdef.is_usb ? "OTG%1u" : "UART%1u", sdef.instance);
uart_thread_ctx = thread_create_alloc(THD_WORKING_AREA_SIZE(HAL_UART_STACK_SIZE),
uart_thread_name,
unbuffered_writes ? APM_UART_UNBUFFERED_PRIORITY : APM_UART_PRIORITY,
uart_thread_trampoline,
this);
if (uart_thread_ctx == nullptr) {
AP_HAL::panic("Could not create UART TX thread\n");
}
}
}
void UARTDriver::uart_thread_trampoline(void* p)
{
UARTDriver* uart = static_cast(p);
uart->uart_thread();
}
#ifndef HAL_STDOUT_SERIAL
/*
hook to allow printf() to work on hal.console when we don't have a
dedicated debug console
*/
static int hal_console_vprintf(const char *fmt, va_list arg)
{
hal.console->vprintf(fmt, arg);
return 1; // wrong length, but doesn't matter for what this is used for
}
#endif
void UARTDriver::begin(uint32_t b, uint16_t rxS, uint16_t txS)
{
thread_rx_init();
if (sdef.serial == nullptr) {
return;
}
uint16_t min_tx_buffer = HAL_UART_MIN_TX_SIZE;
uint16_t min_rx_buffer = HAL_UART_MIN_RX_SIZE;
/*
increase min RX size to ensure we can receive a fully utilised
UART if we are running our receive loop at 40Hz. This means 25ms
of data. Assumes 10 bits per byte, which is normal for most
protocols
*/
bool rx_size_by_baudrate = true;
#if HAL_WITH_IO_MCU
if (this == &uart_io) {
// iomcu doesn't need extra space, just speed
rx_size_by_baudrate = false;
min_tx_buffer = 0;
min_rx_buffer = 0;
}
#endif
if (rx_size_by_baudrate) {
min_rx_buffer = MAX(min_rx_buffer, b/(40*10));
}
if (sdef.is_usb) {
// give more buffer space for log download on USB
min_tx_buffer *= 2;
}
#if HAL_MEM_CLASS >= HAL_MEM_CLASS_500
// on boards with plenty of memory we can use larger buffers
min_tx_buffer *= 2;
min_rx_buffer *= 2;
#endif
// on PX4 we have enough memory to have a larger transmit and
// receive buffer for all ports. This means we don't get delays
// while waiting to write GPS config packets
if (txS < min_tx_buffer) {
txS = min_tx_buffer;
}
if (rxS < min_rx_buffer) {
rxS = min_rx_buffer;
}
/*
allocate the read buffer
we allocate buffers before we successfully open the device as we
want to allocate in the early stages of boot, and cause minimum
thrashing of the heap once we are up. The ttyACM0 driver may not
connect for some time after boot
*/
while (_in_rx_timer) {
hal.scheduler->delay(1);
}
if (rxS != _readbuf.get_size()) {
_rx_initialised = false;
_readbuf.set_size(rxS);
}
bool clear_buffers = false;
if (b != 0) {
// clear buffers on baudrate change, but not on the console (which is usually USB)
if (_baudrate != b && hal.console != this) {
clear_buffers = true;
}
_baudrate = b;
}
if (clear_buffers) {
_readbuf.clear();
}
#ifndef HAL_UART_NODMA
if (!half_duplex && !(_last_options & OPTION_NODMA_RX)) {
if (rx_bounce_buf[0] == nullptr && sdef.dma_rx) {
rx_bounce_buf[0] = (uint8_t *)hal.util->malloc_type(RX_BOUNCE_BUFSIZE, AP_HAL::Util::MEM_DMA_SAFE);
}
if (rx_bounce_buf[1] == nullptr && sdef.dma_rx) {
rx_bounce_buf[1] = (uint8_t *)hal.util->malloc_type(RX_BOUNCE_BUFSIZE, AP_HAL::Util::MEM_DMA_SAFE);
}
}
if (tx_bounce_buf == nullptr && sdef.dma_tx && !(_last_options & OPTION_NODMA_TX)) {
tx_bounce_buf = (uint8_t *)hal.util->malloc_type(TX_BOUNCE_BUFSIZE, AP_HAL::Util::MEM_DMA_SAFE);
}
if (half_duplex) {
rx_dma_enabled = tx_dma_enabled = false;
} else {
rx_dma_enabled = rx_bounce_buf[0] != nullptr && rx_bounce_buf[1] != nullptr;
tx_dma_enabled = tx_bounce_buf != nullptr;
}
if (contention_counter > 1000 && _baudrate <= CONTENTION_BAUD_THRESHOLD) {
// we've previously disabled TX DMA due to contention, don't
// re-enable on a new begin() unless high baudrate
tx_dma_enabled = false;
}
if (_baudrate <= 115200 && sdef.dma_tx && Shared_DMA::is_shared(sdef.dma_tx_stream_id)) {
// avoid DMA on shared low-baudrate links
tx_dma_enabled = false;
}
#endif
#if defined(USART_CR1_FIFOEN)
// enable the UART FIFO on G4 and H7. This allows for much higher baudrates
// without data loss when not using DMA
if (_last_options & OPTION_NOFIFO) {
_cr1_options &= ~USART_CR1_FIFOEN;
} else {
_cr1_options |= USART_CR1_FIFOEN;
}
#endif
/*
allocate the write buffer
*/
while (_in_tx_timer) {
hal.scheduler->delay(1);
}
if (txS != _writebuf.get_size()) {
_tx_initialised = false;
_writebuf.set_size(txS);
}
if (clear_buffers) {
_writebuf.clear();
}
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
/*
* Initializes a serial-over-USB CDC driver.
*/
if (!_device_initialised) {
if ((SerialUSBDriver*)sdef.serial == &SDU1
#if HAL_HAVE_DUAL_USB_CDC
|| (SerialUSBDriver*)sdef.serial == &SDU2
#endif
) {
usb_initialise();
}
_device_initialised = true;
}
#endif
} else {
#if HAL_USE_SERIAL == TRUE
if (_baudrate != 0) {
#ifndef HAL_UART_NODMA
bool was_initialised = _device_initialised;
// setup Rx DMA
if (!_device_initialised) {
if (rx_dma_enabled) {
osalDbgAssert(rxdma == nullptr, "double DMA allocation");
chSysLock();
rxdma = dmaStreamAllocI(sdef.dma_rx_stream_id,
12, //IRQ Priority
(stm32_dmaisr_t)rxbuff_full_irq,
(void *)this);
osalDbgAssert(rxdma, "stream alloc failed");
chSysUnlock();
#if defined(STM32F7) || defined(STM32H7) || defined(STM32F3) || defined(STM32G4) || defined(STM32L4)
dmaStreamSetPeripheral(rxdma, &((SerialDriver*)sdef.serial)->usart->RDR);
#else
dmaStreamSetPeripheral(rxdma, &((SerialDriver*)sdef.serial)->usart->DR);
#endif // STM32F7
#if STM32_DMA_SUPPORTS_DMAMUX
dmaSetRequestSource(rxdma, sdef.dma_rx_channel_id);
#endif
}
_device_initialised = true;
}
if (tx_dma_enabled && dma_handle == nullptr) {
// we only allow for sharing of the TX DMA channel, not the RX
// DMA channel, as the RX side is active all the time, so
// cannot be shared
dma_handle = new Shared_DMA(sdef.dma_tx_stream_id,
SHARED_DMA_NONE,
FUNCTOR_BIND_MEMBER(&UARTDriver::dma_tx_allocate, void, Shared_DMA *),
FUNCTOR_BIND_MEMBER(&UARTDriver::dma_tx_deallocate, void, Shared_DMA *));
if (dma_handle == nullptr) {
tx_dma_enabled = false;
}
}
#endif // HAL_UART_NODMA
sercfg.speed = _baudrate;
// start with options from set_options()
sercfg.cr1 = _cr1_options;
sercfg.cr2 = _cr2_options;
sercfg.cr3 = _cr3_options;
#ifndef HAL_UART_NODMA
if (rx_dma_enabled) {
sercfg.cr1 |= USART_CR1_IDLEIE;
sercfg.cr3 |= USART_CR3_DMAR;
}
if (tx_dma_enabled) {
sercfg.cr3 |= USART_CR3_DMAT;
}
sercfg.irq_cb = rx_irq_cb;
#endif // HAL_UART_NODMA
if (!(sercfg.cr2 & USART_CR2_STOP2_BITS)) {
sercfg.cr2 |= USART_CR2_STOP1_BITS;
}
sercfg.ctx = (void*)this;
sdStart((SerialDriver*)sdef.serial, &sercfg);
#ifndef HAL_UART_NODMA
if (rx_dma_enabled) {
//Configure serial driver to skip handling RX packets
//because we will handle them via DMA
((SerialDriver*)sdef.serial)->usart->CR1 &= ~USART_CR1_RXNEIE;
// Start DMA
if (!was_initialised) {
dmaStreamDisable(rxdma);
dma_rx_enable();
}
}
#endif // HAL_UART_NODMA
}
#endif // HAL_USE_SERIAL
}
if (_writebuf.get_size()) {
_tx_initialised = true;
}
if (_readbuf.get_size()) {
_rx_initialised = true;
}
_uart_owner_thd = chThdGetSelfX();
// initialize the TX thread if necessary
thread_init();
// setup flow control
set_flow_control(_flow_control);
if (serial_num == 0 && _tx_initialised) {
#ifndef HAL_STDOUT_SERIAL
// setup hal.console to take printf() output
vprintf_console_hook = hal_console_vprintf;
#endif
}
}
#ifndef HAL_UART_NODMA
void UARTDriver::dma_tx_allocate(Shared_DMA *ctx)
{
#if HAL_USE_SERIAL == TRUE
if (txdma != nullptr) {
return;
}
chSysLock();
txdma = dmaStreamAllocI(sdef.dma_tx_stream_id,
12, //IRQ Priority
(stm32_dmaisr_t)tx_complete,
(void *)this);
osalDbgAssert(txdma, "stream alloc failed");
chSysUnlock();
#if defined(STM32F7) || defined(STM32H7) || defined(STM32F3) || defined(STM32G4) || defined(STM32L4)
dmaStreamSetPeripheral(txdma, &((SerialDriver*)sdef.serial)->usart->TDR);
#else
dmaStreamSetPeripheral(txdma, &((SerialDriver*)sdef.serial)->usart->DR);
#endif // STM32F7
#if STM32_DMA_SUPPORTS_DMAMUX
dmaSetRequestSource(txdma, sdef.dma_tx_channel_id);
#endif
#endif // HAL_USE_SERIAL
}
#ifndef HAL_UART_NODMA
void UARTDriver::dma_rx_enable(void)
{
uint32_t dmamode = STM32_DMA_CR_DMEIE | STM32_DMA_CR_TEIE;
dmamode |= STM32_DMA_CR_CHSEL(sdef.dma_rx_channel_id);
dmamode |= STM32_DMA_CR_PL(0);
#if defined(STM32H7)
dmamode |= 1<<20; // TRBUFF See 2.3.1 in the H743 errata
#endif
rx_bounce_idx ^= 1;
stm32_cacheBufferInvalidate(rx_bounce_buf[rx_bounce_idx], RX_BOUNCE_BUFSIZE);
dmaStreamSetMemory0(rxdma, rx_bounce_buf[rx_bounce_idx]);
dmaStreamSetTransactionSize(rxdma, RX_BOUNCE_BUFSIZE);
dmaStreamSetMode(rxdma, dmamode | STM32_DMA_CR_DIR_P2M |
STM32_DMA_CR_MINC | STM32_DMA_CR_TCIE);
dmaStreamEnable(rxdma);
}
#endif
void UARTDriver::dma_tx_deallocate(Shared_DMA *ctx)
{
chSysLock();
dmaStreamFreeI(txdma);
txdma = nullptr;
chSysUnlock();
}
#ifndef HAL_UART_NODMA
void UARTDriver::rx_irq_cb(void* self)
{
#if HAL_USE_SERIAL == TRUE
UARTDriver* uart_drv = (UARTDriver*)self;
if (!uart_drv->rx_dma_enabled) {
return;
}
#if defined(STM32F7) || defined(STM32H7)
//disable dma, triggering DMA transfer complete interrupt
uart_drv->rxdma->stream->CR &= ~STM32_DMA_CR_EN;
#elif defined(STM32F3) || defined(STM32G4) || defined(STM32L4)
//disable dma, triggering DMA transfer complete interrupt
dmaStreamDisable(uart_drv->rxdma);
uart_drv->rxdma->channel->CCR &= ~STM32_DMA_CR_EN;
#else
volatile uint16_t sr = ((SerialDriver*)(uart_drv->sdef.serial))->usart->SR;
if(sr & USART_SR_IDLE) {
volatile uint16_t dr = ((SerialDriver*)(uart_drv->sdef.serial))->usart->DR;
(void)dr;
//disable dma, triggering DMA transfer complete interrupt
uart_drv->rxdma->stream->CR &= ~STM32_DMA_CR_EN;
}
#endif // STM32F7
#endif // HAL_USE_SERIAL
}
#endif
/*
handle a RX DMA full interrupt
*/
void UARTDriver::rxbuff_full_irq(void* self, uint32_t flags)
{
#if HAL_USE_SERIAL == TRUE
UARTDriver* uart_drv = (UARTDriver*)self;
if (!uart_drv->rx_dma_enabled) {
return;
}
uint16_t len = RX_BOUNCE_BUFSIZE - dmaStreamGetTransactionSize(uart_drv->rxdma);
const uint8_t bounce_idx = uart_drv->rx_bounce_idx;
// restart the DMA transfers immediately. This switches to the
// other bounce buffer. We restart the DMA before we copy the data
// out to minimise the time with DMA disabled, which allows us to
// handle much higher receiver baudrates
dmaStreamDisable(uart_drv->rxdma);
uart_drv->dma_rx_enable();
if (len > 0) {
/*
we have data to copy out
*/
uart_drv->_readbuf.write(uart_drv->rx_bounce_buf[bounce_idx], len);
uart_drv->receive_timestamp_update();
}
if (uart_drv->_wait.thread_ctx && uart_drv->_readbuf.available() >= uart_drv->_wait.n) {
chSysLockFromISR();
chEvtSignalI(uart_drv->_wait.thread_ctx, EVT_DATA);
chSysUnlockFromISR();
}
if (uart_drv->_rts_is_active) {
uart_drv->update_rts_line();
}
#endif // HAL_USE_SERIAL
}
#endif // HAL_UART_NODMA
void UARTDriver::begin(uint32_t b)
{
if (lock_write_key != 0) {
return;
}
begin(b, 0, 0);
}
void UARTDriver::begin_locked(uint32_t b, uint32_t key)
{
if (lock_write_key != 0 && key != lock_write_key) {
return;
}
begin(b, 0, 0);
}
void UARTDriver::end()
{
while (_in_rx_timer) hal.scheduler->delay(1);
_rx_initialised = false;
while (_in_tx_timer) hal.scheduler->delay(1);
_tx_initialised = false;
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
sduStop((SerialUSBDriver*)sdef.serial);
#endif
} else {
#if HAL_USE_SERIAL == TRUE
sdStop((SerialDriver*)sdef.serial);
#endif
}
_readbuf.set_size(0);
_writebuf.set_size(0);
}
void UARTDriver::flush()
{
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
sduSOFHookI((SerialUSBDriver*)sdef.serial);
#endif
} else {
//TODO: Handle this for other serial ports
}
}
bool UARTDriver::is_initialized()
{
return _tx_initialised && _rx_initialised;
}
void UARTDriver::set_blocking_writes(bool blocking)
{
_blocking_writes = blocking;
}
bool UARTDriver::tx_pending() { return _writebuf.available() > 0; }
/*
get the requested usb baudrate - 0 = none
*/
uint32_t UARTDriver::get_usb_baud() const
{
#if HAL_USE_SERIAL_USB
if (sdef.is_usb) {
return ::get_usb_baud(sdef.endpoint_id);
}
#endif
return 0;
}
/* Empty implementations of Stream virtual methods */
uint32_t UARTDriver::available() {
if (!_rx_initialised || lock_read_key) {
return 0;
}
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
if (((SerialUSBDriver*)sdef.serial)->config->usbp->state != USB_ACTIVE) {
return 0;
}
#endif
}
return _readbuf.available();
}
uint32_t UARTDriver::available_locked(uint32_t key)
{
if (lock_read_key != 0 && key != lock_read_key) {
return -1;
}
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
if (((SerialUSBDriver*)sdef.serial)->config->usbp->state != USB_ACTIVE) {
return 0;
}
#endif
}
return _readbuf.available();
}
uint32_t UARTDriver::txspace()
{
if (!_tx_initialised) {
return 0;
}
return _writebuf.space();
}
bool UARTDriver::discard_input()
{
if (lock_read_key != 0 || _uart_owner_thd != chThdGetSelfX()){
return false;
}
if (!_rx_initialised) {
return false;
}
_readbuf.clear();
if (!_rts_is_active) {
update_rts_line();
}
return true;
}
ssize_t UARTDriver::read(uint8_t *buffer, uint16_t count)
{
if (lock_read_key != 0 || _uart_owner_thd != chThdGetSelfX()){
return -1;
}
if (!_rx_initialised) {
return -1;
}
const uint32_t ret = _readbuf.read(buffer, count);
if (ret == 0) {
return 0;
}
if (!_rts_is_active) {
update_rts_line();
}
return ret;
}
int16_t UARTDriver::read()
{
if (lock_read_key != 0 || _uart_owner_thd != chThdGetSelfX()){
return -1;
}
if (!_rx_initialised) {
return -1;
}
uint8_t byte;
if (!_readbuf.read_byte(&byte)) {
return -1;
}
if (!_rts_is_active) {
update_rts_line();
}
return byte;
}
int16_t UARTDriver::read_locked(uint32_t key)
{
if (lock_read_key != 0 && key != lock_read_key) {
return -1;
}
if (!_rx_initialised) {
return -1;
}
uint8_t byte;
if (!_readbuf.read_byte(&byte)) {
return -1;
}
if (!_rts_is_active) {
update_rts_line();
}
return byte;
}
/* write one byte to the port */
size_t UARTDriver::write(uint8_t c)
{
if (lock_write_key != 0) {
return 0;
}
_write_mutex.take_blocking();
if (!_tx_initialised) {
_write_mutex.give();
return 0;
}
while (_writebuf.space() == 0) {
if (!_blocking_writes || unbuffered_writes) {
_write_mutex.give();
return 0;
}
// release the semaphore while sleeping
_write_mutex.give();
hal.scheduler->delay(1);
_write_mutex.take_blocking();
}
size_t ret = _writebuf.write(&c, 1);
if (unbuffered_writes) {
chEvtSignal(uart_thread_ctx, EVT_TRANSMIT_DATA_READY);
}
_write_mutex.give();
return ret;
}
/* write a block of bytes to the port */
size_t UARTDriver::write(const uint8_t *buffer, size_t size)
{
if (!_tx_initialised || lock_write_key != 0) {
return 0;
}
if (_blocking_writes && !unbuffered_writes) {
/*
use the per-byte delay loop in write() above for blocking writes
*/
size_t ret = 0;
while (size--) {
if (write(*buffer++) != 1) break;
ret++;
}
return ret;
}
WITH_SEMAPHORE(_write_mutex);
size_t ret = _writebuf.write(buffer, size);
if (unbuffered_writes) {
chEvtSignal(uart_thread_ctx, EVT_TRANSMIT_DATA_READY);
}
return ret;
}
/*
lock the uart for exclusive use by write_locked() and read_locked() with the right key
*/
bool UARTDriver::lock_port(uint32_t write_key, uint32_t read_key)
{
if (lock_write_key && write_key != lock_write_key && read_key != 0) {
// someone else is using it
return false;
}
if (lock_read_key && read_key != lock_read_key && read_key != 0) {
// someone else is using it
return false;
}
lock_write_key = write_key;
lock_read_key = read_key;
return true;
}
/*
write to a locked port. If port is locked and key is not correct then 0 is returned
and write is discarded. All writes are non-blocking
*/
size_t UARTDriver::write_locked(const uint8_t *buffer, size_t size, uint32_t key)
{
if (lock_write_key != 0 && key != lock_write_key) {
return 0;
}
WITH_SEMAPHORE(_write_mutex);
return _writebuf.write(buffer, size);
}
/*
wait for data to arrive, or a timeout. Return true if data has
arrived, false on timeout
*/
bool UARTDriver::wait_timeout(uint16_t n, uint32_t timeout_ms)
{
uint32_t t0 = AP_HAL::millis();
while (available() < n) {
chEvtGetAndClearEvents(EVT_DATA);
_wait.n = n;
_wait.thread_ctx = chThdGetSelfX();
uint32_t now = AP_HAL::millis();
if (now - t0 >= timeout_ms) {
break;
}
chEvtWaitAnyTimeout(EVT_DATA, chTimeMS2I(timeout_ms - (now - t0)));
}
return available() >= n;
}
#ifndef HAL_UART_NODMA
#pragma GCC diagnostic push
#pragma GCC diagnostic error "-Wframe-larger-than=128"
/*
DMA transmit completion interrupt handler
*/
void UARTDriver::tx_complete(void* self, uint32_t flags)
{
UARTDriver* uart_drv = (UARTDriver*)self;
chSysLockFromISR();
// check nothing bad happened
if ((flags & STM32_DMA_ISR_TEIF) != 0) {
INTERNAL_ERROR(AP_InternalError::error_t::dma_fail);
}
dmaStreamDisable(uart_drv->txdma);
uart_drv->_last_write_completed_us = AP_HAL::micros();
chEvtSignalI(uart_drv->uart_thread_ctx, EVT_TRANSMIT_DMA_COMPLETE);
chSysUnlockFromISR();
}
/*
write out pending bytes with DMA
*/
void UARTDriver::write_pending_bytes_DMA(uint32_t n)
{
// sanity check
if (!dma_handle) {
return;
}
while (n > 0) {
if (_flow_control != FLOW_CONTROL_DISABLE &&
acts_line != 0 &&
palReadLine(acts_line)) {
// we are using hw flow control and the CTS line is high. We
// will hold off trying to transmit until the CTS line goes
// low to indicate the receiver has space. We do this before
// we take the DMA lock to prevent a high CTS line holding a
// DMA channel that may be needed by another device
return;
}
uint16_t tx_len = 0;
{
WITH_SEMAPHORE(_write_mutex);
// get some more to write
tx_len = _writebuf.peekbytes(tx_bounce_buf, MIN(n, TX_BOUNCE_BUFSIZE));
if (tx_len == 0) {
return; // all done
}
// find out how much is still left to write while we still have the lock
n = MIN(_writebuf.available(), n);
}
dma_handle->lock(); // we have our own thread so grab the lock
chEvtGetAndClearEvents(EVT_TRANSMIT_DMA_COMPLETE);
if (dma_handle->has_contention()) {
// on boards with a hw fifo we can use a higher threshold for disabling DMA
if (_baudrate <= CONTENTION_BAUD_THRESHOLD) {
contention_counter += 3;
if (contention_counter > 1000) {
// more than 25% of attempts to use this DMA
// channel are getting contention and we have a
// low baudrate. Switch off DMA for future
// transmits on this low baudrate UART
tx_dma_enabled = false;
dma_handle->unlock(false);
break;
}
}
/*
someone else is using this same DMA channel. To reduce
latency we will drop the TX size with DMA on this UART to
keep TX times below 250us. This can still suffer from long
times due to CTS blockage
*/
uint32_t max_tx_bytes = 1 + (_baudrate * 250UL / 1000000UL);
if (tx_len > max_tx_bytes) {
tx_len = max_tx_bytes;
}
} else if (contention_counter > 0) {
contention_counter--;
}
chSysLock();
dmaStreamDisable(txdma);
stm32_cacheBufferFlush(tx_bounce_buf, tx_len);
dmaStreamSetMemory0(txdma, tx_bounce_buf);
dmaStreamSetTransactionSize(txdma, tx_len);
uint32_t dmamode = STM32_DMA_CR_DMEIE | STM32_DMA_CR_TEIE;
dmamode |= STM32_DMA_CR_CHSEL(sdef.dma_tx_channel_id);
dmamode |= STM32_DMA_CR_PL(0);
#if defined(STM32H7)
dmamode |= 1<<20; // TRBUFF See 2.3.1 in the H743 errata
#endif
dmaStreamSetMode(txdma, dmamode | STM32_DMA_CR_DIR_M2P |
STM32_DMA_CR_MINC | STM32_DMA_CR_TCIE);
dmaStreamEnable(txdma);
uint32_t timeout_us = ((1000000UL * (tx_len+2) * 10) / _baudrate) + 500;
chSysUnlock();
// wait for the completion or timeout handlers to signal that we are done
eventmask_t mask = chEvtWaitAnyTimeout(EVT_TRANSMIT_DMA_COMPLETE, chTimeUS2I(timeout_us));
// handle a TX timeout. This can happen with using hardware flow
// control if CTS pin blocks transmit or sometimes the DMA completion simply disappears
if (mask == 0) {
chSysLock();
// check whether DMA completion happened in the intervening time
// first disable the stream to prevent further interrupts
dmaStreamDisable(txdma);
const uint32_t tx_size = dmaStreamGetTransactionSize(txdma);
if (tx_size >= tx_len) {
// we didn't write any of our bytes
tx_len = 0;
} else {
// record how much was sent tx_size is how much was
// not sent (could be 0)
tx_len -= tx_size;
}
if (tx_len > 0) {
_last_write_completed_us = AP_HAL::micros();
}
chEvtGetAndClearEvents(EVT_TRANSMIT_DMA_COMPLETE);
chSysUnlock();
}
// clean up pending locks
dma_handle->unlock(mask & EVT_TRANSMIT_DMA_COMPLETE);
if (tx_len) {
WITH_SEMAPHORE(_write_mutex);
// skip over amount actually written
_writebuf.advance(tx_len);
// update stats
_total_written += tx_len;
_tx_stats_bytes += tx_len;
n -= tx_len;
} else {
// if we didn't manage to transmit any bytes then stop
// processing so we can check flow control state in outer
// loop
break;
}
}
}
#pragma GCC diagnostic pop
#endif // HAL_UART_NODMA
/*
write any pending bytes to the device, non-DMA method
*/
void UARTDriver::write_pending_bytes_NODMA(uint32_t n)
{
WITH_SEMAPHORE(_write_mutex);
ByteBuffer::IoVec vec[2];
uint16_t nwritten = 0;
if (half_duplex && n > 1) {
half_duplex_setup_tx();
}
const auto n_vec = _writebuf.peekiovec(vec, n);
for (int i = 0; i < n_vec; i++) {
int ret = -1;
if (sdef.is_usb) {
ret = 0;
#ifdef HAVE_USB_SERIAL
ret = chnWriteTimeout((SerialUSBDriver*)sdef.serial, vec[i].data, vec[i].len, TIME_IMMEDIATE);
#endif
} else {
#if HAL_USE_SERIAL == TRUE
ret = chnWriteTimeout((SerialDriver*)sdef.serial, vec[i].data, vec[i].len, TIME_IMMEDIATE);
#endif
}
if (ret < 0) {
break;
}
if (ret > 0) {
_last_write_completed_us = AP_HAL::micros();
nwritten += ret;
}
_writebuf.advance(ret);
/* We wrote less than we asked for, stop */
if ((unsigned)ret != vec[i].len) {
break;
}
}
_total_written += nwritten;
_tx_stats_bytes += nwritten;
}
/*
write any pending bytes to the device
*/
#pragma GCC diagnostic push
#pragma GCC diagnostic error "-Wframe-larger-than=128"
void UARTDriver::write_pending_bytes(void)
{
// write any pending bytes
uint32_t n = _writebuf.available();
if (n <= 0) {
return;
}
#ifndef HAL_UART_NODMA
if (tx_dma_enabled) {
write_pending_bytes_DMA(n);
} else
#endif
{
write_pending_bytes_NODMA(n);
}
// handle AUTO flow control mode
if (_flow_control == FLOW_CONTROL_AUTO) {
if (_first_write_started_us == 0) {
_first_write_started_us = AP_HAL::micros();
_total_written = 0;
}
#ifndef HAL_UART_NODMA
if (tx_dma_enabled) {
// when we are using DMA we have a reliable indication that a write
// has completed from the DMA completion interrupt
if (_last_write_completed_us != 0) {
_flow_control = FLOW_CONTROL_ENABLE;
return;
}
} else
#endif
{
// without DMA we need to look at the number of bytes written into the queue versus the
// remaining queue space
uint32_t space = qSpaceI(&((SerialDriver*)sdef.serial)->oqueue);
uint32_t used = SERIAL_BUFFERS_SIZE - space;
#if !defined(USART_CR1_FIFOEN)
// threshold is 8 for the GCS_Common code to unstick SiK radios, which
// sends 6 bytes with flow control disabled
const uint8_t threshold = 8;
#else
// account for TX FIFO buffer
uint8_t threshold = 12;
if (_last_options & OPTION_NOFIFO) {
threshold = 8;
}
#endif
if (_total_written > used && _total_written - used > threshold) {
_flow_control = FLOW_CONTROL_ENABLE;
return;
}
}
if (AP_HAL::micros() - _first_write_started_us > 500*1000UL) {
// it doesn't look like hw flow control is working
hal.console->printf("disabling flow control on serial %u\n", sdef.get_index());
set_flow_control(FLOW_CONTROL_DISABLE);
}
}
}
#pragma GCC diagnostic pop
/*
setup for half duplex tramsmit. To cope with uarts that have level
shifters and pullups we need to play a trick where we temporarily
disable half-duplex while transmitting. That disables the receive
part of the uart on the pin which allows the transmit side to
correctly setup the idle voltage before the transmit starts.
*/
void UARTDriver::half_duplex_setup_tx(void)
{
#ifdef HAVE_USB_SERIAL
if (!hd_tx_active) {
chEvtGetAndClearFlags(&hd_listener);
// half-duplex transmission is done when both the output is empty and the transmission is ended
// if we only wait for empty output the line can be setup for receive too soon losing data bits
hd_tx_active = CHN_TRANSMISSION_END | CHN_OUTPUT_EMPTY;
SerialDriver *sd = (SerialDriver*)(sdef.serial);
sdStop(sd);
sercfg.cr3 &= ~USART_CR3_HDSEL;
sdStart(sd, &sercfg);
}
#endif
}
/*
push any pending bytes to/from the serial port. This is called at
1kHz in the timer thread. Doing it this way reduces the system call
overhead in the main task enormously.
*/
void UARTDriver::_rx_timer_tick(void)
{
if (!_rx_initialised || half_duplex) {
return;
}
_in_rx_timer = true;
#ifndef HAL_UART_NODMA
if (rx_dma_enabled && rxdma) {
chSysLock();
//Check if DMA is enabled
//if not, it might be because the DMA interrupt was silenced
//let's handle that here so that we can continue receiving
#if defined(STM32F3) || defined(STM32G4) || defined(STM32L4)
bool enabled = (rxdma->channel->CCR & STM32_DMA_CR_EN);
#else
bool enabled = (rxdma->stream->CR & STM32_DMA_CR_EN);
#endif
if (!enabled) {
uint8_t len = RX_BOUNCE_BUFSIZE - dmaStreamGetTransactionSize(rxdma);
if (len != 0) {
_readbuf.write(rx_bounce_buf[rx_bounce_idx], len);
_rx_stats_bytes += len;
receive_timestamp_update();
if (_rts_is_active) {
update_rts_line();
}
}
// DMA disabled by idle interrupt never got a chance to be handled
// we will enable it here
dmaStreamDisable(rxdma);
dma_rx_enable();
}
chSysUnlock();
}
#endif
// don't try IO on a disconnected USB port
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
if (((SerialUSBDriver*)sdef.serial)->config->usbp->state != USB_ACTIVE) {
_in_rx_timer = false;
return;
}
#endif
}
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
((GPIO *)hal.gpio)->set_usb_connected();
#endif
}
#ifndef HAL_UART_NODMA
if (!rx_dma_enabled)
#endif
{
read_bytes_NODMA();
}
if (_wait.thread_ctx && _readbuf.available() >= _wait.n) {
chEvtSignal(_wait.thread_ctx, EVT_DATA);
}
_in_rx_timer = false;
}
// regular serial read
void UARTDriver::read_bytes_NODMA()
{
// try to fill the read buffer
ByteBuffer::IoVec vec[2];
const auto n_vec = _readbuf.reserve(vec, _readbuf.space());
for (int i = 0; i < n_vec; i++) {
int ret = 0;
//Do a non-blocking read
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
ret = chnReadTimeout((SerialUSBDriver*)sdef.serial, vec[i].data, vec[i].len, TIME_IMMEDIATE);
#endif
} else {
#if HAL_USE_SERIAL == TRUE
ret = chnReadTimeout((SerialDriver*)sdef.serial, vec[i].data, vec[i].len, TIME_IMMEDIATE);
#endif
}
if (ret < 0) {
break;
}
#if CH_CFG_USE_EVENTS == TRUE
if (parity_enabled && ((chEvtGetAndClearFlags(&ev_listener) & SD_PARITY_ERROR))) {
// discard bytes with parity error
ret = -1;
}
#endif
if (!hd_tx_active) {
_readbuf.commit((unsigned)ret);
_rx_stats_bytes += ret;
receive_timestamp_update();
}
/* stop reading as we read less than we asked for */
if ((unsigned)ret < vec[i].len) {
break;
}
}
}
/*
push any pending bytes to/from the serial port. This is called at
1kHz in the timer thread. Doing it this way reduces the system call
overhead in the main task enormously.
*/
void UARTDriver::_tx_timer_tick(void)
{
if (!_tx_initialised) {
return;
}
_in_tx_timer = true;
if (hd_tx_active) {
hd_tx_active &= ~chEvtGetAndClearFlags(&hd_listener);
if (!hd_tx_active) {
/*
half-duplex transmit has finished. We now re-enable the
HDSEL bit for receive
*/
SerialDriver *sd = (SerialDriver*)(sdef.serial);
sdStop(sd);
sercfg.cr3 |= USART_CR3_HDSEL;
sdStart(sd, &sercfg);
}
}
// don't try IO on a disconnected USB port
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
if (((SerialUSBDriver*)sdef.serial)->config->usbp->state != USB_ACTIVE) {
_in_tx_timer = false;
return;
}
#endif
}
if (sdef.is_usb) {
#ifdef HAVE_USB_SERIAL
((GPIO *)hal.gpio)->set_usb_connected();
#endif
}
// half duplex we do reads in the write thread
if (half_duplex) {
_in_rx_timer = true;
read_bytes_NODMA();
if (_wait.thread_ctx && _readbuf.available() >= _wait.n) {
chEvtSignal(_wait.thread_ctx, EVT_DATA);
}
_in_rx_timer = false;
}
// now do the write
write_pending_bytes();
_in_tx_timer = false;
}
/*
change flow control mode for port
*/
void UARTDriver::set_flow_control(enum flow_control flowcontrol)
{
if (sdef.is_usb) {
// no hw flow control available
return;
}
#if HAL_USE_SERIAL == TRUE
SerialDriver *sd = (SerialDriver*)(sdef.serial);
_flow_control = (arts_line == 0) ? FLOW_CONTROL_DISABLE : flowcontrol;
if (!is_initialized()) {
// not ready yet, we just set variable for when we call begin
return;
}
switch (_flow_control) {
case FLOW_CONTROL_DISABLE:
// force RTS active when flow disabled
if (arts_line != 0) {
palSetLineMode(arts_line, 1);
palClearLine(arts_line);
}
_rts_is_active = true;
// disable hardware CTS support
chSysLock();
if ((sd->usart->CR3 & (USART_CR3_CTSE | USART_CR3_RTSE)) != 0) {
sd->usart->CR1 &= ~USART_CR1_UE;
sd->usart->CR3 &= ~(USART_CR3_CTSE | USART_CR3_RTSE);
sd->usart->CR1 |= USART_CR1_UE;
}
chSysUnlock();
break;
case FLOW_CONTROL_AUTO:
// reset flow control auto state machine
_first_write_started_us = 0;
_last_write_completed_us = 0;
FALLTHROUGH;
case FLOW_CONTROL_ENABLE:
// we do RTS in software as STM32 hardware RTS support toggles
// the pin for every byte which loses a lot of bandwidth
palSetLineMode(arts_line, 1);
palClearLine(arts_line);
_rts_is_active = true;
// enable hardware CTS support, disable RTS support as we do that in software
chSysLock();
if ((sd->usart->CR3 & (USART_CR3_CTSE | USART_CR3_RTSE)) != USART_CR3_CTSE) {
// CTSE and RTSE can only be written when uart is disabled
sd->usart->CR1 &= ~USART_CR1_UE;
sd->usart->CR3 |= USART_CR3_CTSE;
sd->usart->CR3 &= ~USART_CR3_RTSE;
sd->usart->CR1 |= USART_CR1_UE;
}
chSysUnlock();
break;
}
#endif // HAL_USE_SERIAL
}
/*
software update of rts line. We don't use the HW support for RTS as
it has no hysteresis, so it ends up toggling RTS on every byte
*/
void UARTDriver::update_rts_line(void)
{
if (arts_line == 0 || _flow_control == FLOW_CONTROL_DISABLE) {
return;
}
uint16_t space = _readbuf.space();
if (_rts_is_active && space < 16) {
_rts_is_active = false;
palSetLine(arts_line);
} else if (!_rts_is_active && space > 32) {
_rts_is_active = true;
palClearLine(arts_line);
}
}
/*
setup unbuffered writes for lower latency
*/
bool UARTDriver::set_unbuffered_writes(bool on)
{
unbuffered_writes = on;
chEvtSignal(uart_thread_ctx, EVT_TRANSMIT_UNBUFFERED);
return true;
}
/*
setup parity
*/
void UARTDriver::configure_parity(uint8_t v)
{
if (sdef.is_usb) {
// not possible
return;
}
#if HAL_USE_SERIAL == TRUE
// stop and start to take effect
sdStop((SerialDriver*)sdef.serial);
#ifdef USART_CR1_M0
// cope with F3 and F7 where there are 2 bits in CR1_M
const uint32_t cr1_m0 = USART_CR1_M0;
#else
const uint32_t cr1_m0 = USART_CR1_M;
#endif
switch (v) {
case 0:
// no parity
sercfg.cr1 &= ~(USART_CR1_PCE | USART_CR1_PS | USART_CR1_M);
break;
case 1:
// odd parity
// setting USART_CR1_M ensures extra bit is used as parity
// not last bit of data
sercfg.cr1 |= cr1_m0 | USART_CR1_PCE;
sercfg.cr1 |= USART_CR1_PS;
break;
case 2:
// even parity
sercfg.cr1 |= cr1_m0 | USART_CR1_PCE;
sercfg.cr1 &= ~USART_CR1_PS;
break;
}
sdStart((SerialDriver*)sdef.serial, &sercfg);
#if CH_CFG_USE_EVENTS == TRUE
if (parity_enabled) {
chEvtUnregister(chnGetEventSource((SerialDriver*)sdef.serial), &ev_listener);
}
parity_enabled = (v != 0);
if (parity_enabled) {
chEvtRegisterMaskWithFlags(chnGetEventSource((SerialDriver*)sdef.serial),
&ev_listener,
EVT_PARITY,
SD_PARITY_ERROR);
}
#endif
#ifndef HAL_UART_NODMA
if (rx_dma_enabled) {
// Configure serial driver to skip handling RX packets
// because we will handle them via DMA
((SerialDriver*)sdef.serial)->usart->CR1 &= ~USART_CR1_RXNEIE;
}
#endif
#endif // HAL_USE_SERIAL
}
/*
set stop bits
*/
void UARTDriver::set_stop_bits(int n)
{
if (sdef.is_usb) {
// not possible
return;
}
#if HAL_USE_SERIAL
// stop and start to take effect
sdStop((SerialDriver*)sdef.serial);
switch (n) {
case 1:
_cr2_options &= ~USART_CR2_STOP2_BITS;
_cr2_options |= USART_CR2_STOP1_BITS;
break;
case 2:
_cr2_options &= ~USART_CR2_STOP1_BITS;
_cr2_options |= USART_CR2_STOP2_BITS;
break;
}
sercfg.cr2 = _cr2_options;
sdStart((SerialDriver*)sdef.serial, &sercfg);
#ifndef HAL_UART_NODMA
if (rx_dma_enabled) {
//Configure serial driver to skip handling RX packets
//because we will handle them via DMA
((SerialDriver*)sdef.serial)->usart->CR1 &= ~USART_CR1_RXNEIE;
}
#endif
#endif // HAL_USE_SERIAL
}
// record timestamp of new incoming data
void UARTDriver::receive_timestamp_update(void)
{
_receive_timestamp[_receive_timestamp_idx^1] = AP_HAL::micros64();
_receive_timestamp_idx ^= 1;
}
/*
return timestamp estimate in microseconds for when the start of
a nbytes packet arrived on the uart. This should be treated as a
time constraint, not an exact time. It is guaranteed that the
packet did not start being received after this time, but it
could have been in a system buffer before the returned time.
This takes account of the baudrate of the link. For transports
that have no baudrate (such as USB) the time estimate may be
less accurate.
A return value of zero means the HAL does not support this API
*/
uint64_t UARTDriver::receive_time_constraint_us(uint16_t nbytes)
{
uint64_t last_receive_us = _receive_timestamp[_receive_timestamp_idx];
if (_baudrate > 0 && !sdef.is_usb) {
// assume 10 bits per byte. For USB we assume zero transport delay
uint32_t transport_time_us = (1000000UL * 10UL / _baudrate) * (nbytes + available());
last_receive_us -= transport_time_us;
}
return last_receive_us;
}
/*
set user specified PULLUP/PULLDOWN options from SERIALn_OPTIONS
*/
void UARTDriver::set_pushpull(uint16_t options)
{
#if HAL_USE_SERIAL == TRUE && !defined(STM32F1)
if ((options & OPTION_PULLDOWN_RX) && arx_line) {
palLineSetPushPull(arx_line, PAL_PUSHPULL_PULLDOWN);
}
if ((options & OPTION_PULLDOWN_TX) && atx_line) {
palLineSetPushPull(atx_line, PAL_PUSHPULL_PULLDOWN);
}
if ((options & OPTION_PULLUP_RX) && arx_line) {
palLineSetPushPull(arx_line, PAL_PUSHPULL_PULLUP);
}
if ((options & OPTION_PULLUP_TX) && atx_line) {
palLineSetPushPull(atx_line, PAL_PUSHPULL_PULLUP);
}
#endif
}
// set optional features, return true on success
bool UARTDriver::set_options(uint16_t options)
{
if (sdef.is_usb) {
// no options allowed on USB
return (options == 0);
}
bool ret = true;
_last_options = options;
#if HAL_USE_SERIAL == TRUE
SerialDriver *sd = (SerialDriver*)(sdef.serial);
uint32_t cr2 = sd->usart->CR2;
uint32_t cr3 = sd->usart->CR3;
bool was_enabled = (sd->usart->CR1 & USART_CR1_UE);
/*
allow for RX, TX, RTS and CTS pins to be remapped via BRD_ALT_CONFIG
*/
arx_line = GPIO::resolve_alt_config(sdef.rx_line, PERIPH_TYPE::UART_RX, sdef.instance);
atx_line = GPIO::resolve_alt_config(sdef.tx_line, PERIPH_TYPE::UART_TX, sdef.instance);
arts_line = GPIO::resolve_alt_config(sdef.rts_line, PERIPH_TYPE::OTHER, sdef.instance);
acts_line = GPIO::resolve_alt_config(sdef.cts_line, PERIPH_TYPE::OTHER, sdef.instance);
// Check flow control, might have to disable if RTS line is gone
set_flow_control(_flow_control);
#if defined(STM32F7) || defined(STM32H7) || defined(STM32F3) || defined(STM32G4) || defined(STM32L4)
// F7 has built-in support for inversion in all uarts
ioline_t rx_line = (options & OPTION_SWAP)?atx_line:arx_line;
ioline_t tx_line = (options & OPTION_SWAP)?arx_line:atx_line;
// if we are half-duplex then treat either inversion option as
// both being enabled. This is easier to understand for users, who
// can be confused as to which pin is the one that needs inversion
if ((options & OPTION_HDPLEX) && (options & (OPTION_TXINV|OPTION_RXINV)) != 0) {
options |= OPTION_TXINV|OPTION_RXINV;
}
if (options & OPTION_RXINV) {
cr2 |= USART_CR2_RXINV;
_cr2_options |= USART_CR2_RXINV;
if (rx_line != 0) {
palLineSetPushPull(rx_line, PAL_PUSHPULL_PULLDOWN);
}
} else {
cr2 &= ~USART_CR2_RXINV;
_cr2_options &= ~USART_CR2_RXINV;
if (rx_line != 0) {
palLineSetPushPull(rx_line, PAL_PUSHPULL_PULLUP);
}
}
if (options & OPTION_TXINV) {
cr2 |= USART_CR2_TXINV;
_cr2_options |= USART_CR2_TXINV;
if (tx_line != 0) {
palLineSetPushPull(tx_line, PAL_PUSHPULL_PULLDOWN);
}
} else {
cr2 &= ~USART_CR2_TXINV;
_cr2_options &= ~USART_CR2_TXINV;
if (tx_line != 0) {
palLineSetPushPull(tx_line, PAL_PUSHPULL_PULLUP);
}
}
// F7 can also support swapping RX and TX pins
if (options & OPTION_SWAP) {
cr2 |= USART_CR2_SWAP;
_cr2_options |= USART_CR2_SWAP;
} else {
cr2 &= ~USART_CR2_SWAP;
_cr2_options &= ~USART_CR2_SWAP;
}
#else // STM32F4
// F4 can do inversion by GPIO if enabled in hwdef.dat, using
// TXINV and RXINV options
if (options & OPTION_RXINV) {
if (sdef.rxinv_gpio >= 0) {
hal.gpio->write(sdef.rxinv_gpio, sdef.rxinv_polarity);
} else {
ret = false;
}
}
if (options & OPTION_TXINV) {
if (sdef.txinv_gpio >= 0) {
hal.gpio->write(sdef.txinv_gpio, sdef.txinv_polarity);
} else {
ret = false;
}
}
if (options & OPTION_SWAP) {
ret = false;
}
#endif // STM32xx
// both F4 and F7 can do half-duplex
if (options & OPTION_HDPLEX) {
cr3 |= USART_CR3_HDSEL;
_cr3_options |= USART_CR3_HDSEL;
if (!half_duplex) {
chEvtRegisterMaskWithFlags(chnGetEventSource((SerialDriver*)sdef.serial),
&hd_listener,
EVT_TRANSMIT_END,
CHN_OUTPUT_EMPTY | CHN_TRANSMISSION_END);
half_duplex = true;
}
#ifndef HAL_UART_NODMA
if (rx_dma_enabled && rxdma) {
dmaStreamDisable(rxdma);
}
#endif
// force DMA off when using half-duplex as the timing may affect other devices
// sharing the DMA channel
rx_dma_enabled = tx_dma_enabled = false;
} else {
cr3 &= ~USART_CR3_HDSEL;
_cr3_options &= ~USART_CR3_HDSEL;
}
set_pushpull(options);
if (sd->usart->CR2 == cr2 &&
sd->usart->CR3 == cr3) {
// no change
return ret;
}
if (was_enabled) {
sd->usart->CR1 &= ~USART_CR1_UE;
}
sd->usart->CR2 = cr2;
sd->usart->CR3 = cr3;
if (was_enabled) {
sd->usart->CR1 |= USART_CR1_UE;
}
#endif // HAL_USE_SERIAL == TRUE
return ret;
}
// get optional features
uint16_t UARTDriver::get_options(void) const
{
return _last_options;
}
#if HAL_UART_STATS_ENABLED
// request information on uart I/O for @SYS/uarts.txt for this uart
void UARTDriver::uart_info(ExpandingString &str)
{
uint32_t now_ms = AP_HAL::millis();
if (sdef.is_usb) {
str.printf("OTG%u ", unsigned(sdef.instance));
} else {
str.printf("UART%u ", unsigned(sdef.instance));
}
str.printf("TX%c=%8u RX%c=%8u TXBD=%6u RXBD=%6u\n",
tx_dma_enabled ? '*' : ' ',
unsigned(_tx_stats_bytes),
rx_dma_enabled ? '*' : ' ',
unsigned(_rx_stats_bytes),
unsigned(_tx_stats_bytes * 10000 / (now_ms - _last_stats_ms)),
unsigned(_rx_stats_bytes * 10000 / (now_ms - _last_stats_ms)));
_tx_stats_bytes = 0;
_rx_stats_bytes = 0;
_last_stats_ms = now_ms;
}
#endif
/*
software control of the CTS pin if available. Return false if
not available
*/
bool UARTDriver::set_CTS_pin(bool high)
{
if (_flow_control != FLOW_CONTROL_DISABLE) {
// CTS pin is being used
return false;
}
if (acts_line == 0) {
// we don't have a CTS pin on this UART
return false;
}
palSetLineMode(acts_line, 1);
palWriteLine(acts_line, high?1:0);
return true;
}
/*
software control of the RTS pin if available. Return false if
not available
*/
bool UARTDriver::set_RTS_pin(bool high)
{
if (_flow_control != FLOW_CONTROL_DISABLE) {
// RTS pin is being used
return false;
}
if (arts_line == 0) {
// we don't have a RTS pin on this UART
return false;
}
palSetLineMode(arts_line, 1);
palWriteLine(arts_line, high?1:0);
return true;
}
#if HAL_USE_SERIAL_USB == TRUE
/*
initialise the USB bus, called from both UARTDriver and stdio for startup debug
This can be called before the hal is initialised so must not call any hal functions
*/
void usb_initialise(void)
{
static bool initialised;
if (initialised) {
return;
}
initialised = true;
sduObjectInit(&SDU1);
sduStart(&SDU1, &serusbcfg1);
#if HAL_HAVE_DUAL_USB_CDC
sduObjectInit(&SDU2);
sduStart(&SDU2, &serusbcfg2);
#endif
/*
* Activates the USB driver and then the USB bus pull-up on D+.
* Note, a delay is inserted in order to not have to disconnect the cable
* after a reset.
*/
usbDisconnectBus(serusbcfg1.usbp);
chThdSleep(chTimeUS2I(1500));
usbStart(serusbcfg1.usbp, &usbcfg);
usbConnectBus(serusbcfg1.usbp);
}
#endif
// disable TX/RX pins for unusued uart
void UARTDriver::disable_rxtx(void) const
{
if (arx_line) {
palSetLineMode(arx_line, PAL_MODE_INPUT);
}
if (atx_line) {
palSetLineMode(atx_line, PAL_MODE_INPUT);
}
}
#endif //CONFIG_HAL_BOARD == HAL_BOARD_CHIBIOS