1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
/**
* @file conversion.cpp
* @brief Manages algorithm application (converts input samples to output).
*
* Copyright (C) 2021 Clyne Sullivan
*
* Distributed under the GNU GPL v3 or later. You should have received a copy of
* the GNU General Public License along with this program.
* If not, see <https://www.gnu.org/licenses/>.
*/
#include "conversion.hpp"
#include "periph/adc.hpp"
#include "periph/dac.hpp"
#include "elfload.hpp"
#include "error.hpp"
#include "runstatus.hpp"
#include "samples.hpp"
// MSG_* things below are macros rather than constexpr
// to ensure inlining.
#define MSG_CONVFIRST (1)
#define MSG_CONVSECOND (2)
#define MSG_CONVFIRST_MEASURE (3)
#define MSG_CONVSECOND_MEASURE (4)
#define MSG_FOR_FIRST(msg) (msg & 1)
#define MSG_FOR_MEASURE(msg) (msg > 2)
__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, THD_WORKING_AREA_SIZE(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::startMeasurement()
{
ADC::setOperation(adcReadHandlerMeasure);
}
void ConversionManager::stop()
{
DAC::stop(0);
ADC::stop();
}
thread_t *ConversionManager::getMonitorHandle()
{
return m_thread_monitor;
}
void ConversionManager::abort(bool fpu_stacked)
{
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() -
(fpu_stacked ? 26 : 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));
volatile auto testRead = *samples;
(void)testRead;
} 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));
volatile auto testRead = *samples;
(void)testRead;
}
}
// 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);
}
|
