m-labs · Jun 28, 2016 · Jun 28, 2016
diff --git a/artiq/coredevice/core.py b/artiq/coredevice/core.py
@@ -37,6 +37,10 @@ def __str__(self):
         return "\n" + _render_diagnostic(self.diagnostic, colored=colors_supported)
 
 
+@syscall
+def rtio_init():
+    raise NotImplementedError("syscall not simulated")
+
 @syscall(flags={"nounwind", "nowrite"})
 def rtio_get_counter() -> TInt64:
     raise NotImplementedError("syscall not simulated")
@@ -121,10 +125,21 @@ def set_result(new_result):
     def get_rtio_counter_mu(self):
         return rtio_get_counter()
 
+    @kernel
+    def reset(self):
+        """Clear RTIO FIFOs, release RTIO PHY reset, and set the time cursor
+        at the current value of the hardware RTIO counter plus a margin of
+        125000 machine units."""
+        rtio_init()
+        at_mu(rtio_get_counter() + 125000)
+
     @kernel
     def break_realtime(self):
-        """Set the timeline to the current value of the hardware RTIO counter
-        plus a margin of 125000 machine units."""
+        """Set the time cursor after the current value of the hardware RTIO
+        counter plus a margin of 125000 machine units.
+
+        If the time cursor is already after that position, this function
+        does nothing."""
         min_now = rtio_get_counter() + 125000
         if now_mu() < min_now:
             at_mu(min_now)
diff --git a/artiq/examples/master/idle_kernel.py b/artiq/examples/master/idle_kernel.py
@@ -0,0 +1,21 @@
+from artiq.experiment import *
+
+
+class IdleKernel(EnvExperiment):
+    def build(self):
+        self.setattr_device("core")
+        self.setattr_device("led")
+
+    @kernel
+    def run(self):
+        start_time = now_mu() + seconds_to_mu(500*ms)
+        while self.core.get_rtio_counter_mu() < start_time:
+            pass
+        self.core.reset()
+        while True:
+            self.led.pulse(250*ms)
+            delay(125*ms)
+            self.led.pulse(125*ms)
+            delay(125*ms)
+            self.led.pulse(125*ms)
+            delay(250*ms)
diff --git a/artiq/examples/master/repository/coredevice_examples/pdq2_simple.py b/artiq/examples/master/repository/coredevice_examples/pdq2_simple.py
@@ -38,6 +38,7 @@ def one(self):
         return self.pmt.count()
 
     def run(self):
+        self.core.reset()
         offsets = np.arange(0, 3)
         for o in offsets:
             self.setup(o)

diff --git a/artiq/examples/master/repository/coredevice_examples/photon_histogram.py b/artiq/examples/master/repository/coredevice_examples/photon_histogram.py
@@ -48,6 +48,7 @@ def cool_detect(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.program_cooling()
 
         hist = [0 for _ in range(self.nbins)]

diff --git a/artiq/examples/master/repository/coredevice_examples/simple/ad5360.py b/artiq/examples/master/repository/coredevice_examples/simple/ad5360.py
@@ -9,6 +9,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.dac.setup_bus(write_div=30, read_div=40)
         self.dac.write_offsets()
         self.led.on()

diff --git a/artiq/examples/master/repository/coredevice_examples/simple/blink_forever.py b/artiq/examples/master/repository/coredevice_examples/simple/blink_forever.py
@@ -8,6 +8,7 @@ def build(self):
 
     @kernel
     def run(self):
+    	self.core.reset()
         while True:
             self.led.pulse(100*ms)
             delay(100*ms)
diff --git a/artiq/examples/master/repository/coredevice_examples/simple/dds_test.py b/artiq/examples/master/repository/coredevice_examples/simple/dds_test.py
@@ -17,6 +17,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         with self.core_dds.batch:
             self.dds1.set(120*MHz)
             self.dds2.set(200*MHz)

diff --git a/artiq/examples/master/repository/coredevice_examples/simple/handover.py b/artiq/examples/master/repository/coredevice_examples/simple/handover.py
@@ -12,5 +12,6 @@ def blink_once(self):
         delay(250*ms)
 
     def run(self):
+        self.core.reset()
         while True:
             self.blink_once()
diff --git a/artiq/examples/master/repository/coredevice_examples/tdr.py b/artiq/examples/master/repository/coredevice_examples/tdr.py
@@ -36,6 +36,7 @@ def build(self):
         self.setattr_device("ttl2")
 
     def run(self):
+        self.core.reset()
         n = 1000  # repetitions
         latency = 50e-9  # calibrated latency without a transmission line
         pulse = 1e-6  # pulse length, larger than rtt

diff --git a/artiq/examples/master/repository/coredevice_examples/transport.py b/artiq/examples/master/repository/coredevice_examples/transport.py
@@ -91,6 +91,7 @@ def scan(self, stops):
             self.repeat()
 
     def run(self):
+        self.core.reset()
         # scan transport endpoint
         stops = np.linspace(0, 10, 10)
         self.scan(stops)

diff --git a/artiq/runtime/kloader.c b/artiq/runtime/kloader.c
@@ -149,7 +149,7 @@ int kloader_is_essential_kmsg(int msgtype)
     }
 }
 
-long long int now;
+static long long int now = 0;
 
 void kloader_service_essential_kmsg(void)
 {

diff --git a/artiq/runtime/kloader.h b/artiq/runtime/kloader.h
@@ -8,8 +8,6 @@
 #define KERNELCPU_LAST_ADDRESS    (0x4fffffff - 1024*1024)
 #define KSUPPORT_HEADER_SIZE      0x80
 
-extern long long int now;
-
 int kloader_load_library(const void *code);
 void kloader_filter_backtrace(struct artiq_backtrace_item *backtrace,
                               size_t *backtrace_size);

diff --git a/artiq/runtime/ksupport.c b/artiq/runtime/ksupport.c
@@ -111,6 +111,7 @@ static const struct symbol runtime_exports[] = {
     {"recv_rpc", &recv_rpc},
 
     /* direct syscalls */
+    {"rtio_init", &rtio_init},
     {"rtio_get_counter", &rtio_get_counter},
     {"rtio_log", &rtio_log},
     {"rtio_output", &rtio_output},
@@ -351,11 +352,6 @@ static void now_init(void)
     }
     now = reply->now;
     mailbox_acknowledge();
-
-    if(now < 0) {
-        rtio_init();
-        now = rtio_get_counter() + (272000 << CONFIG_RTIO_FINE_TS_WIDTH);
-    }
 }
 
 static void now_save(void)
@@ -475,7 +471,6 @@ void send_rpc(int service, const char *tag, ...)
 {
     struct msg_rpc_send request;
 
-    request.now = now;
     if(service != 0)
         request.type = MESSAGE_TYPE_RPC_SEND;
     else

diff --git a/artiq/runtime/messages.h b/artiq/runtime/messages.h
@@ -87,7 +87,6 @@ struct msg_watchdog_clear {
 
 struct msg_rpc_send {
     int type;
-    long long int now;
     int service;
     const char *tag;
     va_list args;

diff --git a/artiq/runtime/session.c b/artiq/runtime/session.c
@@ -300,7 +300,6 @@ void session_startup_kernel(void)
 {
     struct msg_base *umsg;
 
-    now = -1;
     watchdog_init();
     if(!kloader_start_startup_kernel())
         return;
@@ -341,14 +340,12 @@ void session_start(void)
     out_packet_reset();
 
     kloader_stop();
-    now = -1;
     user_kernel_state = USER_KERNEL_NONE;
 }
 
 void session_end(void)
 {
     kloader_stop();
-    now = -1;
     watchdog_init();
     kloader_start_idle_kernel();
 }
@@ -983,12 +980,6 @@ static int process_kmsg(struct msg_base *umsg)
         case MESSAGE_TYPE_RPC_BATCH: {
             struct msg_rpc_send *msg = (struct msg_rpc_send *)umsg;
 
-            /*
-             * save now in case the RPC stops the kernel
-             * (e.g. pause with preemption)
-             */
-            now = msg->now;
-
             if(!send_rpc_request(msg->service, msg->tag, msg->args)) {
                 core_log("Failed to send RPC request (service %d, tag %s)\n",
                          msg->service, msg->tag);

diff --git a/artiq/test/coredevice/test_analyzer.py b/artiq/test/coredevice/test_analyzer.py
@@ -13,6 +13,7 @@ def build(self):
 
     @kernel
     def initialize_io(self):
+        self.core.reset()
         self.loop_in.input()
         self.loop_out.off()
 
@@ -33,6 +34,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         rtio_log("foo", 32)
 
 

diff --git a/artiq/test/coredevice/test_embedding.py b/artiq/test/coredevice/test_embedding.py
@@ -12,6 +12,7 @@ def build(self):
     def roundtrip(self, obj, fn):
         fn(obj)
 
+
 class RoundtripTest(ExperimentCase):
     def assertRoundtrip(self, obj):
         exp = self.create(_Roundtrip)
@@ -55,6 +56,7 @@ def test(self, foo=42) -> TInt32:
     def run(self):
         return self.test()
 
+
 class DefaultArgTest(ExperimentCase):
     def test_default_arg(self):
         exp = self.create(_DefaultArg)
@@ -103,6 +105,7 @@ def args1kwargs2(self):
     def builtin(self):
         sleep(1.0)
 
+
 class RPCTest(ExperimentCase):
     def test_args(self):
         exp = self.create(_RPC)
@@ -128,6 +131,7 @@ def run(self):
         data = [0 for _ in range(1000000//4)]
         self.devnull(data)
 
+
 class LargePayloadTest(ExperimentCase):
     def test_1MB(self):
         exp = self.create(_Payload1MB)

diff --git a/artiq/test/coredevice/test_rtio.py b/artiq/test/coredevice/test_rtio.py
@@ -24,6 +24,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.ttl_inout.output()
         delay(1*us)
         with interleave:
@@ -48,6 +49,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.loop_in.input()
         self.loop_out.off()
         delay(1*us)
@@ -71,6 +73,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.loop_clock_in.input()
         self.loop_clock_out.stop()
         delay(1*us)
@@ -89,6 +92,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         dt = seconds_to_mu(300*ns)
         while True:
             for i in range(10000):
@@ -113,6 +117,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         dt = seconds_to_mu(5*us)
         while True:
             delay(10*ms)
@@ -154,6 +159,7 @@ def set_count(self, count):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.loop_in.input()
         self.loop_out.output()
         delay(5*us)
@@ -173,6 +179,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         while True:
             delay(25*ns)
             self.ttl_out.pulse(25*ns)
@@ -185,6 +192,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         t = now_mu()
         self.ttl_out.pulse(25*us)
         at_mu(t)
@@ -198,6 +206,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         delay(5*ms)  # make sure we won't get underflow
         for i in range(16):
             self.ttl_out_serdes.pulse_mu(1)
@@ -211,6 +220,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         self.loop_in.input()
         self.loop_in.pulse(10*us)
 

diff --git a/artiq/test/coredevice/test_spi.py b/artiq/test/coredevice/test_spi.py
@@ -13,7 +13,7 @@ def build(self):
 
     @kernel
     def run(self):
-        self.core.break_realtime()
+        self.core.reset()
         t = now_mu()
         try:
             self.spi0.set_config_mu()
@@ -31,8 +31,8 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         try:
-            self.core.break_realtime()
             self.spi0.set_config_mu()
             t = now_mu()
             self.spi0.set_config_mu()
@@ -54,6 +54,7 @@ def build(self):
 
     @kernel
     def run(self):
+        self.core.reset()
         while True:
             try:
                 self.core.break_realtime()