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#include "conversion.hpp"
#include "periph/adc.hpp"
#include "periph/dac.hpp"
#include "elfload.hpp"
#include "error.hpp"
#include "runstatus.hpp"
#include "samples.hpp"
constexpr msg_t MSG_CONVFIRST = 1;
constexpr msg_t MSG_CONVSECOND = 2;
constexpr msg_t MSG_CONVFIRST_MEASURE = 3;
constexpr msg_t MSG_CONVSECOND_MEASURE = 4;
constexpr auto MSG_FOR_FIRST = [](msg_t m) { return m & 1; };
constexpr auto MSG_FOR_MEASURE = [](msg_t m) { return m > 2; };
time_measurement_t conversion_time_measurement;
__attribute__((section(".convdata")))
thread_t *ConversionManager::m_thread_monitor = nullptr;
thread_t *ConversionManager::m_thread_runner = nullptr;
__attribute__((section(".stacks")))
std::array<char, 1024> ConversionManager::m_thread_monitor_stack = {};
__attribute__((section(".stacks")))
std::array<char, 128> ConversionManager::m_thread_runner_entry_stack = {};
__attribute__((section(".convdata")))
std::array<char, CONVERSION_THREAD_STACK_SIZE> ConversionManager::m_thread_runner_stack = {};
std::array<msg_t, 2> ConversionManager::m_mailbox_buffer;
mailbox_t ConversionManager::m_mailbox = _MAILBOX_DATA(m_mailbox, m_mailbox_buffer.data(), m_mailbox_buffer.size());
void ConversionManager::begin()
{
m_thread_monitor = chThdCreateStatic(m_thread_monitor_stack.data(),
m_thread_monitor_stack.size(),
NORMALPRIO + 1,
threadMonitor,
nullptr);
auto runner_stack_end = &m_thread_runner_stack[CONVERSION_THREAD_STACK_SIZE];
m_thread_runner = chThdCreateStatic(m_thread_runner_entry_stack.data(),
m_thread_runner_entry_stack.size(),
HIGHPRIO,
threadRunnerEntry,
runner_stack_end);
}
void ConversionManager::start()
{
Samples::Out.clear();
ADC::start(Samples::In.data(), Samples::In.size(), adcReadHandler);
DAC::start(0, Samples::Out.data(), Samples::Out.size());
}
void ConversionManager::startMeasured()
{
Samples::Out.clear();
ADC::start(Samples::In.data(), Samples::In.size(), adcReadHandlerMeasure);
DAC::start(0, Samples::Out.data(), Samples::Out.size());
}
void ConversionManager::stop()
{
DAC::stop(0);
ADC::stop();
}
thread_t *ConversionManager::getMonitorHandle()
{
return m_thread_monitor;
}
void ConversionManager::abort()
{
ELFManager::unload();
EM.add(Error::ConversionAborted);
run_status = RunStatus::Recovering;
// Confirm that the exception return thread is the algorithm...
uint32_t *psp;
asm("mrs %0, psp" : "=r" (psp));
bool isRunnerStack =
(uint32_t)psp >= reinterpret_cast<uint32_t>(m_thread_runner_stack.data()) &&
(uint32_t)psp <= reinterpret_cast<uint32_t>(m_thread_runner_stack.data() +
m_thread_runner_stack.size());
if (isRunnerStack)
{
// If it is, we can force the algorithm to exit by "resetting" its thread.
// We do this by rebuilding the thread's stacked exception return.
auto newpsp = reinterpret_cast<uint32_t *>(m_thread_runner_stack.data() +
m_thread_runner_stack.size() -
8 * sizeof(uint32_t));
// Set the LR register to the thread's entry point.
newpsp[5] = reinterpret_cast<uint32_t>(threadRunner);
// Overwrite the instruction we'll return to with "bx lr" (jump to address in LR).
newpsp[6] = psp[6];
*reinterpret_cast<uint16_t *>(newpsp[6]) = 0x4770; // "bx lr"
// Keep PSR contents (bit set forces Thumb mode, just in case).
newpsp[7] = psp[7] | (1 << 24);
// Set the new stack pointer.
asm("msr psp, %0" :: "r" (newpsp));
}
}
void ConversionManager::threadMonitor(void *)
{
while (1) {
msg_t message;
msg_t fetch = chMBFetchTimeout(&m_mailbox, &message, TIME_INFINITE);
if (fetch == MSG_OK)
chMsgSend(m_thread_runner, message);
}
}
void ConversionManager::threadRunnerEntry(void *stack)
{
ELFManager::unload();
port_unprivileged_jump(reinterpret_cast<uint32_t>(threadRunner),
reinterpret_cast<uint32_t>(stack));
}
__attribute__((section(".convcode")))
void ConversionManager::threadRunner(void *)
{
while (1) {
// Sleep until we receive a mailbox message.
msg_t message;
asm("svc 0; mov %0, r0" : "=r" (message));
if (message != 0) {
auto samples = MSG_FOR_FIRST(message) ? Samples::In.data()
: Samples::In.middata();
auto size = Samples::In.size() / 2;
auto entry = ELFManager::loadedElf();
if (entry) {
// Below, we remember the stack pointer just in case the
// loaded algorithm messes things up.
uint32_t sp;
if (!MSG_FOR_MEASURE(message)) {
asm("mov %0, sp" : "=r" (sp));
samples = entry(samples, size);
asm("mov sp, %0" :: "r" (sp));
} else {
// Start execution timer:
asm("mov %0, sp; eor r0, r0; svc 2" : "=r" (sp));
samples = entry(samples, size);
// Stop execution timer:
asm("mov r0, #1; svc 2; mov sp, %0" :: "r" (sp));
}
}
// Update the sample out buffer with the transformed samples.
if (samples != nullptr) {
if (MSG_FOR_FIRST(message))
Samples::Out.modify(samples, size);
else
Samples::Out.midmodify(samples, size);
}
}
}
}
void ConversionManager::adcReadHandler(adcsample_t *buffer, size_t)
{
chSysLockFromISR();
// If previous request hasn't been handled, then we're going too slow.
// We'll need to abort.
if (chMBGetUsedCountI(&m_mailbox) > 1) {
chMBResetI(&m_mailbox);
chMBResumeX(&m_mailbox);
chSysUnlockFromISR();
abort();
} else {
// Mark the modified samples as 'fresh' or ready for manipulation.
if (buffer == Samples::In.data()) {
Samples::In.setModified();
chMBPostI(&m_mailbox, MSG_CONVFIRST);
} else {
Samples::In.setMidmodified();
chMBPostI(&m_mailbox, MSG_CONVSECOND);
}
chSysUnlockFromISR();
}
}
void ConversionManager::adcReadHandlerMeasure(adcsample_t *buffer, size_t)
{
chSysLockFromISR();
if (buffer == Samples::In.data()) {
Samples::In.setModified();
chMBPostI(&m_mailbox, MSG_CONVFIRST_MEASURE);
} else {
Samples::In.setMidmodified();
chMBPostI(&m_mailbox, MSG_CONVSECOND_MEASURE);
}
chSysUnlockFromISR();
ADC::setOperation(adcReadHandler);
}
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