alchitry-loader/bit2bin.py

@@ -1,90 +0,0 @@
-#!/usr/bin/env python
-
-import argparse
-import struct
-
-
-def flip32(data: bytes):
-    sl = struct.Struct('<I')
-    sb = struct.Struct('>I')
-    d = bytearray(len(data))
-    for offset in range(0, len(data), 4):
-         sb.pack_into(d, offset, sl.unpack_from(data, offset)[0])
-    return d
-
-
-def parse_args():
-    parser = argparse.ArgumentParser(description='Convert FPGA bit files to raw bin format suitable for flashing')
-    parser.add_argument('-f', '--flip', dest='flip', action='store_true', default=False, help='Flip 32-bit endianess (needed for Zynq)')
-    parser.add_argument("bitfiletemplate", help="Input bit file name from which the header is extracted")
-    parser.add_argument("binfile", help="Input bin file name from which the bitstream is extracted")
-    parser.add_argument("bitfile", help="Output bit file name")
-    return parser.parse_args()
-
-
-def main():
-    args = parse_args()
-    short = struct.Struct('>H')
-    ulong = struct.Struct('>I')
-
-    bitfile = open(args.bitfiletemplate, 'rb')
-    headerLength = 0
-    l = short.unpack(bitfile.read(2))[0]
-    headerLength = headerLength + 2
-    if l != 9:
-        raise Exception("Missing <0009> header (0x%x), not a bit file" % l)
-    bitfile.read(l)
-    headerLength = headerLength + l
-    l = short.unpack(bitfile.read(2))[0]
-    d = bitfile.read(l)
-    headerLength = headerLength + l + 2
-    if d != b'a':
-        raise Exception("Missing <a> header, not a bit file")
-
-    l = short.unpack(bitfile.read(2))[0]
-    d = bitfile.read(l)
-    headerLength = headerLength + l +2
-    print("Design name: %s" % d)
-
-    KEYNAMES = {b'b': "Partname", b'c': "Date", b'd': "Time"}
-
-    while 1:
-        k = bitfile.read(1)
-        headerLength = headerLength + 1
-        if not k:
-            bitfile.close()
-            raise Exception("unexpected EOF")
-        elif k == b'e':
-            l = ulong.unpack(bitfile.read(4))[0]
-            headerLength = headerLength + 4
-            print("Found header end: %d" % headerLength)
-            break
-        elif k in KEYNAMES:
-            l = short.unpack(bitfile.read(2))[0]
-            d = bitfile.read(l)
-            headerLength = headerLength + l + 2
-            print(KEYNAMES[k], d)
-        else:
-            print("Unexpected key: %s" % k)
-            l = short.unpack(bitfile.read(2))[0]
-            d = bitfile.read(l)
-            headerLength = headerLength + l + 2 
-
-    outputfile = open(args.bitfile, 'wb+')
-    bitfile.seek(0)
-    outputfile.write(bitfile.read(headerLength))
-    bitfile.close()
-
-    binfile = open( args.binfile, 'rb')
-    d = binfile.read()
-    binfile.close()
-    if args.flip:
-        print("Flipping data...")
-        d = flip32(d)
-
-    outputfile.write(d)
-    outputfile.close()
-
-
-if __name__ == "__main__":
-    main()

arm/async.cc

@@ -5,9 +5,22 @@
 #include <chrono>
 #include <utility>
 
-#include "lock.h"
 #include "trace.h"
 
+#ifdef __x86_64__
+#include <mutex>
+struct InterruptLock {
+    static std::mutex m;
+    InterruptLock() { m.lock(); }
+    ~InterruptLock() { m.unlock(); }
+};
+std::mutex InterruptLock::m;
+#else  // __x86_64__
+#include "lock.h"
+
+using tracing::trace;
+#endif  // __x86_64__
+
 namespace async {
 namespace {
 
@@ -25,14 +38,13 @@ struct Notification {
     Stuff* stuff;
 };
 
-std::atomic<Stuff*> work = nullptr;
+std::atomic<Stuff*> work;
 std::array<Notification, static_cast<size_t>(AwaitableType::kNumTypes)>
     notifications = {};
 
 }  // namespace
 
 void schedule(std::coroutine_handle<> h, int ms) {
-    InterruptLock lock;
     TRACE(tracing::TraceEvent::kAsyncSchedule);
     std::chrono::system_clock::time_point exp =
         std::chrono::system_clock::now() + std::chrono::milliseconds(ms);
@@ -58,64 +70,38 @@ void schedule(std::coroutine_handle<> h, int ms) {
     s->next = news;
 }
 
-void step() {
-    Stuff* stuff;
-    // ensure all previous side effects are visible
-    {
-        InterruptLock lock;
-        stuff = work;
-    };
-
-    if (stuff == nullptr) {
-        return;
-    }
-
-    auto now = std::chrono::system_clock::now();
-    auto dt = stuff->expiration - now;
-
-    if (dt > 0ms) {
-        return;
-    }
-
-    int stuffinqueue = 0;
-    for (Stuff* s = stuff; s; s = s->next) stuffinqueue++;
-
-    TRACE(tracing::TraceEvent::kAsyncTask);
-    stuff->h();
-    TRACE(tracing::TraceEvent::kAsyncTaskDone);
-
-    if (stuff->h.done()) {
-        stuff->h.destroy();
-    }
-
-    {
-        InterruptLock lock;
-        work = stuff->next;
-    }
-    delete stuff;
-}
-
-void reset() {
-    Stuff* stuff = work;
-    while (stuff) {
-        Stuff* byebye = stuff;
-        stuff = stuff->next;
-
-        delete byebye;
-    }
-    work = nullptr;
-}
-
 void main_loop(bool (*idle_function)()) {
     while (1) {
         if (idle_function != nullptr) {
             if (idle_function()) {
-                reset();
                 break;
             };
         }
+        Stuff* stuff = work;
+        if (stuff == nullptr) {
+            continue;  // busyloop
+        }
 
-        step();
+        auto now = std::chrono::system_clock::now();
+        auto dt = stuff->expiration - now;
+
+        if (dt > 0ms) {
+            continue;
+        }
+
+        TRACE(tracing::TraceEvent::kAsyncTask);
+        stuff->h();
+        TRACE(tracing::TraceEvent::kAsyncTaskDone);
+
+        if (stuff->h.done()) {
+            stuff->h.destroy();
+        }
+        {
+            InterruptLock lock;
+
+            work = stuff->next;
+        }
+        delete stuff;
     }
 }
 
@@ -165,4 +151,31 @@ void resume(AwaitableType type) {
     delete stuff;
 }
 
-}  // namespace async
+}  // namespace async
+
+#if 0
+ 
+task<buffer> readline() {
+  int size = 0;
+  char c;
+ 
+  buffer buff = buffer::make(32);
+ 
+//  fcntl(0, F_SETFL, fcntl(0, F_GETFL) | O_NONBLOCK);
+ 
+  while (true) {
+    int n = read(0, &c, 1);
+    if (n < 1) {
+      co_await co_waitio();
+      continue;
+    }
+    buff.data[size++] = static_cast<std::byte>(c);
+ 
+    if (c == '\n') {
+      buff.data = buff.data.subspan(0, size);
+      co_return buff;
+    }
+  }
+}
+
+#endif  // 0

arm/async.h

@@ -1,11 +1,19 @@
 #pragma once
 
-#include <coroutine>
 #include <chrono>
 #include <utility>
 
 #include "trace.h"
 
+#ifdef __clang__
+#include <experimental/coroutine>
+namespace std {
+using namespace experimental;
+}
+#else  // __clang__
+#include <coroutine>
+#endif  // __clang__
+
 namespace async {
 
 struct task_final_suspend {
@@ -15,11 +23,6 @@ struct task_final_suspend {
             TRACE(tracing::TraceEvent::kAsyncCallParent);
             parent();
             TRACE(tracing::TraceEvent::kAsyncCallParentDone);
-
-            if (parent && parent.done()) {
-                TRACE(tracing::TraceEvent::kAsyncDestroy);
-                parent.destroy();
-            }
         }
     }
     void await_resume() noexcept(true) {}
@@ -35,6 +38,12 @@ struct gimme {
         ha = h;
         waiting = true;
         TRACE(tracing::TraceEvent::kAsyncGimmeWaiting);
+
+        if (parent) {
+            TRACE(tracing::TraceEvent::kAsyncCallParent);
+            parent.resume();
+            TRACE(tracing::TraceEvent::kAsyncCallParentDone);
+        }
     }
     T await_resume() {
         waiting = false;
@@ -43,7 +52,23 @@ struct gimme {
     }
 
     // parent interface
-    void feed(T&& s) {
+    auto feed(T&& s) {
+        struct awaitable {
+            bool await_ready() {
+                if (g.waiting) {
+                    return true;
+                }
+                // TODO: handle g.ha.done()
+                return false;
+            }
+            void await_suspend(std::coroutine_handle<> h) {
+                g.parent = h;
+            }
+            void await_resume() {}
+
+            gimme<T>& g;
+        };
+
         if (!waiting) {
            __builtin_trap();
         }
@@ -51,12 +76,16 @@ struct gimme {
            __builtin_trap();
         }
         stuff = s;
+        parent = {};
         ha.resume();
+
+        return awaitable{.g = *this};
     }
 
     bool waiting = false;
     std::coroutine_handle<> ha;
     T stuff;
+    std::coroutine_handle<> parent;
 };
 
 template <typename T = void>
@@ -88,8 +117,7 @@ struct task<void> {
         TRACE(tracing::TraceEvent::kAsyncCoAwait);
         h();
         if (h.done()) {
-            TRACE(tracing::TraceEvent::kAsyncDestroy);
-            h.destroy();
+            TRACE(tracing::TraceEvent::kAsyncDestroy); h.destroy();
             return true;
         }
         return false;
@@ -177,8 +205,7 @@ void schedule(std::coroutine_handle<> h, int ms = 0);
 void enqueue(std::coroutine_handle<> h, AwaitableType type);
 void resume(AwaitableType type);  // typically called from an ISR
 
-void main_loop(bool (*idle_function)());
-void step();
+void main_loop(void (*idle_function)());
 
 inline auto await(AwaitableType type) {
     struct awaitable {

arm/async_test.cc

@@ -7,7 +7,6 @@
 #include <atomic>
 #include <chrono>
 #include <cstdio>
-#include <mutex>
 #include <semaphore>
 #include <thread>
 
@@ -29,14 +28,11 @@ int uptime() {
 
 template <typename... Args>
 void log(int i, const char* fmt, Args... args) {
-    if (i != 3) {
+    if (i != 4) {
         return;
     }
     printf("[%10i] ", uptime());
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wformat-security"
     printf(fmt, args...);
-#pragma clang diagnostic pop
     printf("\n");
 }
 
@@ -128,7 +124,6 @@ TEST_F(LoopAsyncTest, ManyEnqueueResume) {
     }
 
     EXPECT_EQ(done, kLoops);
-    log(3, "got all of em, done");
 
     terminate = true;
     t.join();
@@ -201,14 +196,10 @@ std::binary_semaphore NestedAsync::next(0);
 std::binary_semaphore NestedAsync::ready(0);
 
 TEST_F(NestedAsync, SimpleNestedTest) {
-    while (next.try_acquire());
-    while (ready.try_acquire());
-
     async::schedule(nested().h);
     std::thread t([]() {
         async::main_loop([]() -> bool {
-            // for some reason the bare `acquire` fails sometimes :/
-            while (!next.try_acquire_for(10ms));
+            next.acquire();
             return terminate;
         });
     });
@@ -231,23 +222,39 @@ TEST_F(NestedAsync, SimpleNestedTest) {
 
 TEST_F(NestedAsync, LessSimpleNestedTest) {
     async::schedule(othernested().h);
+    std::thread t([]() {
+        async::main_loop([]() -> bool {
+            ready.release();
+            log(3, "loop ready");
+            next.acquire();
+            return terminate;
+        });
+    });
 
     ASSERT_FALSE(voiddone);
     ASSERT_EQ(result, 0);
 
-    log(3, "step");
-    async::step();  // should proceed until yield
+    log(3, "starting stuff");
+
+    ASSERT_TRUE(ready.try_acquire_for(1s));
+    next.release();
+    ASSERT_TRUE(ready.try_acquire_for(1s));
 
     ASSERT_FALSE(voiddone);
     ASSERT_EQ(result, 0);
 
-    log(3, "step");
-    async::step();  // should proceed until end
+    next.release();
+    ASSERT_TRUE(ready.try_acquire_for(1s));
 
     EXPECT_EQ(voiddone, true);
     ASSERT_EQ(result, 42);
 
     EXPECT_TRUE(done.try_acquire_for(1s));
+
+    terminate = true;
+    next.release();
+
+    t.join();
 }
 
 TEST_F(NestedAsync, GeneratorTest) {

arm/crash.cc

@@ -3,7 +3,6 @@
 #include "gpio.h"
 #include "itoa.h"
 #include "sleep.h"
-#include "trace.h"
 #include "uart.h"
 
 extern "C" uint32_t _initial_stack_pointer, _text_begin, _text_end;
@@ -81,8 +80,6 @@ void CrashHandler(Armv6mRegs* regs) {
     UartWriteCrash("- Stack trace:\r\n");
     StackTrace(reinterpret_cast<uint32_t*>(regs->sp));
 
-    tracing::dump();
-
     while (1) {
         gpio0->data = 0x55;
         sleep(100);

arm/dev.dockerfile

@@ -1,5 +0,0 @@
-FROM ubuntu
-
-RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
-    apt-get install -y make clang libgmock-dev gdb && \
-    apt-get clean && rm -rf /var/lib/apt/lists

arm/fake_uart.cc

@@ -1,202 +0,0 @@
-#include "uart.h"
-
-#include "async.h"
-#include "buffer.h"
-#include "ring_buffer.h"
-
-#include <array>
-#include <mutex>
-#include <vector>
-
-namespace {
-using async::AwaitableType;
-
-constexpr size_t kUartTxBufferSize = 256;
-std::array<std::byte, kUartTxBufferSize> tx_buffer = {};
-RingBuffer tx_ring_buffer{.buffer = tx_buffer};
-
-uint8_t* tx_buff = nullptr;
-uint16_t tx_size = 0;
-uint16_t tx_size_orig = 0;
-
-uint8_t* rx_buff = nullptr;
-uint16_t rx_size = 0;
-uint16_t rx_size_orig = 0;
-std::vector<std::byte> rx_overflow;
-
-std::mutex interrupt_lock;
-std::mutex fu_mutex;
-}  // namespace
-
-//// Internal API
-void FakeUart_Send(uint8_t* ptr, uint16_t size) {
-    std::scoped_lock lock(fu_mutex);
-
-    tx_buff = ptr;
-    tx_size = size;
-    tx_size_orig = size;
-}
-size_t FakeUart_Recv(uint8_t* ptr, uint16_t size) {
-    std::scoped_lock lock(fu_mutex);
-
-    if (size <= rx_overflow.size()) {
-        std::copy(rx_overflow.begin(), rx_overflow.begin() + size,
-                  std::as_writable_bytes(std::span{ptr, size}).begin());
-        std::rotate(rx_overflow.begin(), rx_overflow.begin() + size, rx_overflow.end());
-        rx_overflow.resize(rx_overflow.size() - size);
-
-        return size;
-    }
-
-    rx_buff = ptr;
-    rx_size = size;
-
-    if (rx_overflow.empty()) {
-        return 0;
-    }
-
-    std::copy(rx_overflow.begin(), rx_overflow.end(),
-              std::as_writable_bytes(std::span{ptr, size}).begin());
-    size_t copied = rx_overflow.size();
-    rx_overflow.clear();
-
-    rx_buff += copied;
-    rx_size -= copied;
-
-    return copied;
-}
-uint8_t FakeUart_IsSending() {
-    std::scoped_lock lock(fu_mutex);
-    return tx_size > 0;
-}
-
-//// Backdoor access API
-/// Those do trigger UART interrupts when tx/rx buffer state changes
-buffer FakeUart_Drain(uint16_t size) {
-    std::scoped_lock isr_lock(interrupt_lock);  // not really the same, but that'll do
-    std::scoped_lock lock(fu_mutex);
-
-    size_t drained = std::min(size, tx_size);
-
-    if (drained < 1) { 
-        return buffer{};
-    }
-
-    buffer buff = buffer::make(drained);
-    auto txb = std::as_bytes(std::span{tx_buff, tx_size});
-    std::copy(txb.begin(), txb.begin() + drained, buff.data.begin());
-
-    tx_buff += drained;
-    tx_size -= drained;
-
-    if (tx_size < 1) {
-        fu_mutex.unlock();
-        HandleUartTxFromIsr(nullptr, tx_size_orig);
-        fu_mutex.lock();
-    }
-
-    return buff;
-}
-void FakeUart_Feed(std::span<const std::byte> data) {
-    std::scoped_lock lock(fu_mutex);
-
-    if (data.empty()) {
-        return;
-    }
-
-    auto rxb = std::as_writable_bytes(std::span{rx_buff, rx_size});
-    size_t fed = std::min(static_cast<size_t>(rx_size), data.size());
-
-    if (data.size() > fed) {
-        rx_overflow.insert(rx_overflow.end(), data.begin() + fed, data.end());
-    }
-
-    if (fed > 0) {
-        std::copy(data.begin(), data.begin() + fed, rxb.begin());
-
-        rx_buff += fed;
-        rx_size -= fed;
-
-        if (rx_size < 1) {
-            HandleUartRxFromIsr(nullptr, rx_size_orig);
-        }
-    }
-}
-void FakeUart_Reset() {
-    rx_overflow.clear();
-
-    rx_buff = nullptr;
-    rx_size = 0;
-    tx_buff = nullptr;
-    tx_size = 0;
-}
-
-//// Public API
-void InitUarts() {}
-void UartWriteCrash(std::span<const std::byte>) {}
-void LogStuff() {}
-void UartReadBlocking(std::span<std::byte>) {}
-void UartWriteBlocking(std::span<const std::byte>) {}
-void HandleUartIsr() {}
-async::task<buffer> UartRead(int size) {
-    co_return buffer{};
-}
-
-void HandleUartTxFromIsr(void*, unsigned int transmitted) {
-    tx_ring_buffer.Pop(transmitted);
-    if (tx_ring_buffer.AvailableData() > 0 && !FakeUart_IsSending()) {
-        FakeUart_Send(tx_ring_buffer.RawReadPointer(),
-                       tx_ring_buffer.ContiguousAvailableData());
-    }
-    async::resume(AwaitableType::kUartTx);
-}
-
-void HandleUartRxFromIsr(void*, unsigned int) {
-    async::resume(AwaitableType::kUartRx);
-}
-
-async::task<> UartWrite(std::span<const std::byte> data) {
-    while (!tx_ring_buffer.Store(data)) {
-        co_await async::await(AwaitableType::kUartTx);
-    }
-
-    {
-        std::scoped_lock lock(interrupt_lock);
-
-        if (!FakeUart_IsSending()) {
-            FakeUart_Send(tx_ring_buffer.RawReadPointer(),
-                          tx_ring_buffer.ContiguousAvailableData());
-        }
-    }
-}
-
-async::task<> UartWriteLoop(async::gimme<std::span<const std::byte>>& data_gen) {
-    while (1) {
-        auto data = co_await data_gen;
-        while (!tx_ring_buffer.Store(data)) {
-            co_await async::await(AwaitableType::kUartTx);
-        }
-
-        {
-            std::scoped_lock lock(interrupt_lock);
-
-            if (tx_ring_buffer.AvailableData() && !FakeUart_IsSending()) {
-                FakeUart_Send(tx_ring_buffer.RawReadPointer(),
-                              tx_ring_buffer.ContiguousAvailableData());
-            }
-        }
-    }
-}
-
-async::task<uint8_t> UartReadLoop() {
-    uint8_t c;
-    while (1) {
-        size_t received = FakeUart_Recv(&c, 1);
-        // some data may already be in the fifo, but if not, wait:
-        if (received < 1) {
-            co_await async::await(AwaitableType::kUartRx);
-        }
-
-        co_yield c;
-    }
-}

arm/fake_uart.h

@@ -1,10 +0,0 @@
-#pragma once
-
-#include <cstdint>
-#include <span>
-
-#include "buffer.h"
-
-buffer FakeUart_Drain(uint16_t size);
-void FakeUart_Feed(std::span<const std::byte> data);
-void FakeUart_Reset();

arm/lock.cc

@@ -1,5 +0,0 @@
-#include "lock.h"
-
-#ifdef __x86_64__
-std::recursive_mutex InterruptLock::m;
-#endif

arm/lock.h

@@ -1,23 +1,15 @@
 #pragma once
 
-#ifndef __x86_64__
 #include "aum1_cm1.h"
 
 struct InterruptLock {
-    uint32_t old_primask;
+    bool was_locked;
 
-    InterruptLock() : old_primask(__get_PRIMASK()) { __disable_irq(); }
+    InterruptLock() : was_locked(__get_PRIMASK() != 0) { __disable_irq(); }
 
     ~InterruptLock() {
-        __set_PRIMASK(old_primask);
+        if (!was_locked) {
+            __enable_irq();
+        }
     }
 };
-#else  // __x86_64__
-#include <mutex>
-
-struct InterruptLock {
-    static std::recursive_mutex m;
-    InterruptLock() { m.lock(); }
-    ~InterruptLock() { m.unlock(); }
-};
-#endif  // __x86_64__

arm/main.cc

@@ -14,12 +14,14 @@ namespace {
 using async::AwaitableType;
 
 void Uart0Isr() {
-    ToggleLed(7);
-    //tracing::trace(tracing::TraceEvent::kUartIsr);
+    tracing::trace(tracing::TraceEvent::kUartIsr);
     HandleUartIsr();
 }
 
-void Timer0Isr() { __builtin_trap(); }
+void Timer0Isr() {
+    tracing::dump();
+    __builtin_trap();
+}
 
 void SetupUart() {
     InitUarts();
@@ -30,81 +32,35 @@ void SetupUart() {
 }
 
 void SetupTimer() {
-    timer0->SetupAsWdt(100000 * 1); //4000);
+    timer0->SetupAsWdt(100000 * 4000);
     timer0->EnableT1();
 
     _vector_table[16 + Timer0_IRQn] = reinterpret_cast<uint32_t>(Timer0Isr);
     NVIC_EnableIRQ(Timer0_IRQn);
 }
 
-
-#if 1 // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101133
 async::task<> echo() {
-    async::task<uint8_t> reader = UartReadLoop();
-    async::gimme<std::span<const std::byte>> feeder;
-    async::task<> writer = UartWriteLoop(feeder);
-    writer.h.resume();  // advance to first yield
     while (1) {
-        SetLed(1);
-        uint8_t c = co_await reader;
-        ClearLed(1);
-        ToggleLed(2);
-        feeder.feed(std::as_bytes(std::span{&c, 1}));
-    }
-}
-#else
-async::task<> echo() {
-    async::task<uint8_t> reader = UartReadLoop();
-    while (1) {
-        SetLed(1);
-        uint8_t c = co_await reader;
-        ClearLed(1);
-        ToggleLed(2);
-        co_await UartWrite(std::as_bytes(std::span{&c, 1}));
-    }
-}
-#endif
-
-[[maybe_unused]]
-async::task<> dump_trace() {
-    while (1) {
-        co_await async::delay(5000);
-//        tracing::dump();
+        buffer buff = co_await UartRead(1);
+        co_await UartWrite(buff.data);
     }
 }
 }  // namespace
 
-#define XUL_SR_RX_FIFO_FULL 0x02       /* receive FIFO full */
-#define XUL_SR_RX_FIFO_VALID_DATA 0x01 /* data in receive FIFO */
-
 int main() {
     _vector_table[16 + HardFault_IRQn] =
         reinterpret_cast<uint32_t>(crash::HardFaultHandler);
 
     SetupUart();
-    UartWriteBlocking("uart setup done\r\n");
     SetupTimer();
-    UartWriteBlocking("timer setup done\r\n");
 
     async::schedule(echo().h);
-//    async::schedule(dump_trace().h);
-
-    tracing::trace(tracing::TraceEvent::kUartIsr);
-    tracing::trace(tracing::TraceEvent::kUartIsr);
-
-    UartWriteBlocking("init done. starting main loop\r\n");
 
     async::main_loop([]() {
         static int cnt = 0;
         timer0->Pet();
         if ((cnt++ % 100000) == 0) {
             ToggleLed(0);
-            ClearLed(7);
-            ClearLed(2);
-            ClearLed(3);
-            ClearLed(4);
-
-            LogStuff();
         }
         return false;
     });

arm/makefile

@@ -4,7 +4,7 @@ CXX = arm-none-eabi-g++
 OBJCOPY = arm-none-eabi-objcopy
 
 linker_script = bootloader.ld
-includes =
+includes = 
 sources =
 
 CFLAGS = -march=armv6-m -g -ffunction-sections -fdata-sections -Os -Werror -Wall -flto
@@ -43,7 +43,10 @@ app.elf: $(app_objects) app.ld
 
 deps = $(app_objects:.o=.d) $(bootloader_objects:.o=.d)
 
-HOSTCXX = clang++
+clean:
+	rm -rf *.elf *.bin $(tests) $(app_objects) $(bootloader_objects) $(deps)
+
+HOSTCXX = /usr/local/opt/llvm/bin/clang++
 HOSTLDFLAGS = -lgmock -lgtest -lgtest_main -L/usr/local/opt/llvm/lib -L/usr/local/lib
 HOSTCFLAGS = -std=c++20 -g\
 			 -I/usr/local/opt/llvm/include \
@@ -54,39 +57,31 @@ HOSTCFLAGS = -std=c++20 -g\
 TSAN_CFLAGS = $(HOSTCFLAGS) -fsanitize=thread
 ASAN_CFLAGS = $(HOSTCFLAGS) -fsanitize=address -fsanitize=leak
 
-tests = ring_buffer_test.run async_test_asan.run async_test_tsan.run uart_test_tsan.run
+tests = ring_buffer_test async_test_asan async_test_tsan
+
+.PRECIOUS: $(tests)
 
 test: $(tests)
 
-test/async_test_asan: async_test.cc async.host.o lock.host.o
-test/async_test_tsan: async_test.cc async.host.o lock.host.o
-test/ring_buffer_test: ring_buffer_test.cc lock.host.o
-test/uart_test_tsan: uart_test.cc fake_uart.host.o async.host.o lock.host.o
-
-%.run: test/%
-	TSAN_OPTIONS='suppressions=tsan.suppressions' ASAN_OPTIONS=detect_leaks=1 ./$<
+ring_buffer_test: ring_buffer_test.cc
+	mkdir test
+	$(HOSTCXX) $(HOSTCFLAGS) -o test/$@ $< $(HOSTLDFLAGS)
+	./test/$@
 
 %.host.o: %.cc
 	$(HOSTCXX) $(HOSTCFLAGS) -c -o $@ $<
 
-test/%_test: | mktest
-	$(HOSTCXX) $(HOSTCFLAGS) -o $@ $^ $(HOSTLDFLAGS)
-
-test/%_asan: | mktest
-	$(HOSTCXX) $(ASAN_CFLAGS) -o $@ $^ $(HOSTLDFLAGS)
-
-test/%_tsan: | mktest
-	$(HOSTCXX) $(TSAN_CFLAGS) -o $@ $^ $(HOSTLDFLAGS)
-
-mktest:
+async_test_tsan: async_test.cc async.host.o
 	mkdir -p test
+	$(HOSTCXX) $(TSAN_CFLAGS) -o test/$@ $^ $(HOSTLDFLAGS)
+	TSAN_OPTIONS='suppressions=tsan.suppressions' ./test/$@
 
-test_deps = async.host.d lock.host.d fake_uart.host.d
+async_test_asan: async_test.cc async.host.o
+	mkdir -p test
+	$(HOSTCXX) $(ASAN_CFLAGS) -o test/$@ $^ $(HOSTLDFLAGS)
+	ASAN_OPTIONS=detect_leaks=1 ./test/$@
 
-
-clean:
-	rm -rf *.elf *.bin $(app_objects) $(bootloader_objects) $(deps)
-	rm -rf test/ *.dSYM $(test_deps) *.o
+test_deps = async.host.d
 
 -include $(deps)
--include $(test_deps)
+-include $(test_deps)

arm/prog.py

@@ -1,7 +1,6 @@
 import serial
 import struct
 import sys
-import time
 
 offset = 0x800
 tty = 'tty'
@@ -42,17 +41,6 @@ def main():
     s = serial.Serial(tty, baud, timeout=1)
     write(s, offset, dat)
     jump(s, offset)
-    last_dat = time.time()
-
-    while True:
-        dat = s.read()
-        if not dat:
-            if time.time() - last_dat > 1.0:
-                print('Data timeout')
-                break
-            continue
-        last_dat = time.time()
-        sys.stdout.buffer.write(dat)
 
 
 if __name__ == "__main__":

arm/ring_buffer.h

@@ -3,8 +3,6 @@
 #include <atomic>
 #include <span>
 
-#include "lock.h"
-
 struct RingBuffer {
     std::span<std::byte> buffer;
 
@@ -13,8 +11,6 @@ struct RingBuffer {
     std::atomic<bool> full = 0;
 
     bool Store(std::span<const std::byte> data) {
-        InterruptLock lock;
-
         if (data.size() > FreeSpace()) {
             return false;
         }
@@ -30,8 +26,6 @@ struct RingBuffer {
     }
 
     bool Load(std::span<std::byte> out) {
-        InterruptLock lock;
-
         if (out.size() > AvailableData()) {
             return false;
         }
@@ -47,8 +41,6 @@ struct RingBuffer {
     }
 
     bool Push(size_t amount) {
-        InterruptLock lock;
-
         if (amount > FreeSpace()) {
             return false;
         }
@@ -60,8 +52,6 @@ struct RingBuffer {
     }
 
     bool Pop(size_t amount) {
-        InterruptLock lock;
-
         if (amount > AvailableData()) {
             return false;
         }
@@ -72,15 +62,9 @@ struct RingBuffer {
         return true;
     }
 
-    size_t FreeSpace() const {
-        InterruptLock lock;
-
-        return buffer.size() - AvailableData();
-    }
+    size_t FreeSpace() const { return buffer.size() - AvailableData(); }
 
     size_t AvailableData() const {
-        InterruptLock lock;
-
         if (read_ptr == write_ptr) {
             return full ? buffer.size() : 0;
         }
@@ -88,14 +72,10 @@ struct RingBuffer {
     }
 
     uint8_t* RawReadPointer() const {
-        InterruptLock lock;
-
         return reinterpret_cast<uint8_t*>(buffer.data() + read_ptr);
     }
 
     size_t ContiguousAvailableData() const {
-        InterruptLock lock;
-
         if (read_ptr < write_ptr) {
             return AvailableData();
         }

arm/stdlib.cc

@@ -7,19 +7,14 @@
 #include "timer.h"
 #include "uart.h"
 
-#ifndef SBRK_STATS
-#define SBRK_STATS 0
-#endif
-
 extern unsigned char _heap_begin, _heap_end;
 
 namespace {
-[[maybe_unused]]
 void LogStats(unsigned char* heap) {
     char number[] = "00000000\r\n";
-    UartWriteCrash("Program break now at 0x");
+    UartWriteBlocking("Program break now at 0x");
     itoa(reinterpret_cast<int>(heap), number);
-    UartWriteCrash(number);
+    UartWriteBlocking(number);
 }
 }  // namespace
 
@@ -27,13 +22,11 @@ extern "C" void* _sbrk(int increment) {
     static unsigned char* heap = &_heap_begin;
     unsigned char* prev_heap = heap;
     if (heap + increment >= &_heap_end) {
-        UartWriteCrash("Heap overflow!\r\n");
+        UartWriteBlocking("Heap overflow!\r\n");
         return reinterpret_cast<void*>(-1);
     }
     heap += increment;
-#if SBRK_STATS
     LogStats(heap);
-#endif
     return prev_heap;
 }
 

arm/uart.cc

@@ -70,7 +70,7 @@ async::task<> UartWrite(std::span<const std::byte> data) {
     }
 }
 
-#define GCC_HAS_BUG_101133 0  // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101133
+#define GCC_HAS_BUG_101133 1  // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101133
 #if !GCC_HAS_BUG_101133
 async::task<> UartWriteLoop(async::gimme<std::span<const std::byte>>& data_gen) {
     while (1) {

arm/uart_test.cc

@@ -1,95 +0,0 @@
-#include "uart.h"
-#include "uart_async.h"
-#include "fake_uart.h"
-
-#include <gmock/gmock.h>
-#include <gtest/gtest.h>
-
-#include <atomic>
-#include <chrono>
-#include <semaphore>
-#include <thread>
-
-using namespace ::testing;
-
-namespace {
-std::atomic<bool> terminate;
-std::counting_semaphore<12345> got_stuff(0);
-
-buffer rx;
-
-using namespace std::literals::chrono_literals;
-}
-
-std::string drain_n(size_t n, std::chrono::system_clock::duration timeout) {
-    std::string txtout;
-    auto begin = std::chrono::system_clock::now();
-
-    while (std::chrono::system_clock::now() < begin + timeout) {
-        auto out = FakeUart_Drain(n);
-        if (out.data.empty()) {
-            continue;
-        }
-
-        auto strout = std::string_view(reinterpret_cast<char*>(out.data.data()),
-                                       out.data.size());
-        n -= out.data.size();
-        txtout.append(strout);
-        if (n < 1) {
-            return txtout;
-        }
-    }
-    return "";
-}
-
-TEST(Uart, BasicSend) {
-    FakeUart_Reset();
-    terminate = false;
-
-    constexpr std::string_view kTestData = "blarg";
-    auto buff = std::as_bytes(std::span{kTestData});
-
-    async::schedule(UartWrite(buff).h);
-    std::thread t(
-        []() { async::main_loop([]() -> bool { return terminate; }); });
-
-    std::string strout = drain_n(kTestData.size(), 1s);
-    EXPECT_EQ(strout, kTestData);
-
-    terminate = true;
-    t.join();
-}
-
-async::task<> test_echo() {
-    async::task<uint8_t> reader = UartReadLoop();
-    async::gimme<std::span<const std::byte>> feeder;
-    async::task<> writer = UartWriteLoop(feeder);
-    writer.h.resume();  // advance to first yield
-    while (1) {
-        uint8_t c = co_await reader;
-        feeder.feed(std::as_bytes(std::span{&c, 1}));
-        got_stuff.release();
-    }
-}
-
-TEST(Uart, Echo) {
-    FakeUart_Reset();
-    terminate = false;
-
-    constexpr std::string_view kTestData = "blargblaektrkblalasrjkh1!!";
-    auto buff = std::as_bytes(std::span{kTestData});
-
-    async::schedule(test_echo().h);
-    std::thread t(
-        []() { async::main_loop([]() -> bool { return terminate; }); });
-
-    for (int j = 0; j < 100; j++) {
-        FakeUart_Feed(buff);
-        std::string txtout = drain_n(kTestData.size(), 1s);
-
-        ASSERT_EQ(txtout, kTestData);
-    }
-
-    terminate = true;
-    t.join();
-}