ardupilot/libraries/AP_HAL_ChibiOS/Device.cpp

191 lines
6.1 KiB
C++
Raw Normal View History

/*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "Device.h"
#include <AP_HAL/AP_HAL.h>
#include <AP_HAL/utility/OwnPtr.h>
#include <stdio.h>
#include "Scheduler.h"
#include "Semaphores.h"
#include "Util.h"
using namespace ChibiOS;
static const AP_HAL::HAL &hal = AP_HAL::get_HAL();
/*
per-bus callback thread
*/
void DeviceBus::bus_thread(void *arg)
{
struct DeviceBus *binfo = (struct DeviceBus *)arg;
while (true) {
uint64_t now = AP_HAL::micros64();
DeviceBus::callback_info *callback;
// find a callback to run
for (callback = binfo->callbacks; callback; callback = callback->next) {
if (now >= callback->next_usec) {
while (now >= callback->next_usec) {
callback->next_usec += callback->period_usec;
}
// call it with semaphore held
if (binfo->semaphore.take(HAL_SEMAPHORE_BLOCK_FOREVER)) {
callback->cb();
binfo->semaphore.give();
}
}
}
// work out when next loop is needed
uint64_t next_needed = 0;
now = AP_HAL::micros64();
for (callback = binfo->callbacks; callback; callback = callback->next) {
if (next_needed == 0 ||
callback->next_usec < next_needed) {
next_needed = callback->next_usec;
if (next_needed < now) {
next_needed = now;
}
}
}
// delay for at most 50ms, to handle newly added callbacks
uint32_t delay = 50000;
if (next_needed >= now && next_needed - now < delay) {
delay = next_needed - now;
}
// don't delay for less than 400usec, so one thread doesn't
// completely dominate the CPU
if (delay < 100) {
delay = 100;
}
hal.scheduler->delay_microseconds(delay);
}
return;
}
AP_HAL::Device::PeriodicHandle DeviceBus::register_periodic_callback(uint32_t period_usec, AP_HAL::Device::PeriodicCb cb, AP_HAL::Device *_hal_device)
{
if (!thread_started) {
thread_started = true;
hal_device = _hal_device;
// setup a name for the thread
const uint8_t name_len = 7;
char *name = (char *)malloc(name_len);
switch (hal_device->bus_type()) {
case AP_HAL::Device::BUS_TYPE_I2C:
snprintf(name, name_len, "I2C:%u",
hal_device->bus_num());
break;
case AP_HAL::Device::BUS_TYPE_SPI:
snprintf(name, name_len, "SPI:%u",
hal_device->bus_num());
break;
default:
break;
}
thread_ctx = chThdCreateFromHeap(NULL,
THD_WORKING_AREA_SIZE(1024),
name,
thread_priority, /* Initial priority. */
DeviceBus::bus_thread, /* Thread function. */
this); /* Thread parameter. */
}
DeviceBus::callback_info *callback = new DeviceBus::callback_info;
if (callback == nullptr) {
return nullptr;
}
callback->cb = cb;
callback->period_usec = period_usec;
callback->next_usec = AP_HAL::micros64() + period_usec;
// add to linked list of callbacks on thread
callback->next = callbacks;
callbacks = callback;
return callback;
}
/*
* Adjust the timer for the next call: it needs to be called from the bus
* thread, otherwise it will race with it
*/
bool DeviceBus::adjust_timer(AP_HAL::Device::PeriodicHandle h, uint32_t period_usec)
{
if (chThdGetSelfX() != thread_ctx) {
return false;
}
DeviceBus::callback_info *callback = static_cast<DeviceBus::callback_info *>(h);
callback->period_usec = period_usec;
callback->next_usec = AP_HAL::micros64() + period_usec;
return true;
}
/*
setup to use DMA-safe bouncebuffers for device transfers
*/
void DeviceBus::bouncebuffer_setup(const uint8_t *&buf_tx, uint16_t tx_len,
uint8_t *&buf_rx, uint16_t rx_len)
{
if (buf_tx && !IS_DMA_SAFE(buf_tx)) {
if (tx_len > bounce_buffer_tx_size) {
if (bounce_buffer_tx_size) {
hal.util->free_type(bounce_buffer_tx, bounce_buffer_tx_size, AP_HAL::Util::MEM_DMA_SAFE);
bounce_buffer_tx_size = 0;
}
bounce_buffer_tx = (uint8_t *)hal.util->malloc_type(tx_len, AP_HAL::Util::MEM_DMA_SAFE);
if (bounce_buffer_tx == nullptr) {
AP_HAL::panic("Out of memory for DMA TX");
}
bounce_buffer_tx_size = tx_len;
}
memcpy(bounce_buffer_tx, buf_tx, tx_len);
buf_tx = bounce_buffer_tx;
}
if (buf_rx && !IS_DMA_SAFE(buf_rx)) {
if (rx_len > bounce_buffer_rx_size) {
if (bounce_buffer_rx_size) {
hal.util->free_type(bounce_buffer_rx, bounce_buffer_rx_size, AP_HAL::Util::MEM_DMA_SAFE);
bounce_buffer_rx_size = 0;
}
bounce_buffer_rx = (uint8_t *)hal.util->malloc_type(rx_len, AP_HAL::Util::MEM_DMA_SAFE);
if (bounce_buffer_rx == nullptr) {
AP_HAL::panic("Out of memory for DMA RX");
}
bounce_buffer_rx_size = rx_len;
}
buf_rx = bounce_buffer_rx;
}
}
/*
complete a transfer using DMA bounce buffer
*/
void DeviceBus::bouncebuffer_rx_copy(uint8_t *buf_rx, uint16_t rx_len)
{
memcpy(buf_rx, bounce_buffer_rx, rx_len);
}