rtio: error recovery

soc/artiqlib/rtio/core.py

@@ -8,8 +8,8 @@ from artiqlib.rtio.rbus import get_fine_ts_width
 
 
 class _RTIOBankO(Module):
-    def __init__(self, rbus, counter_width, fine_ts_width,
+    def __init__(self, rbus, counter, fine_ts_width, fifo_depth):
-                 fifo_depth, counter_init):
+        counter_width = flen(counter)
         self.sel = Signal(max=len(rbus))
         self.timestamp = Signal(counter_width+fine_ts_width)
         self.value = Signal(2)
@@ -18,16 +18,13 @@ class _RTIOBankO(Module):
         self.replace = Signal()
         self.underflow = Signal()
         self.level = Signal(bits_for(fifo_depth))
-        self.counter = Signal(counter_width, reset=counter_init)
 
         # # #
 
-        self.sync += self.counter.eq(self.counter + 1)
-
         # detect underflows
         self.sync += \
             If((self.we & self.writable) | self.replace,
-                If(self.timestamp[fine_ts_width:] < self.counter + 2,
+                If(self.timestamp[fine_ts_width:] < counter + 2,
                     self.underflow.eq(1))
             )
 
@@ -50,7 +47,7 @@ class _RTIOBankO(Module):
             # FIFO read
             self.comb += [
                 chif.o_stb.eq(fifo.readable &
-                    (fifo.dout.timestamp[fine_ts_width:] == self.counter)),
+                    (fifo.dout.timestamp[fine_ts_width:] == counter)),
                 chif.o_value.eq(fifo.dout.value),
                 fifo.re.eq(chif.o_stb)
             ]
@@ -66,7 +63,8 @@ class _RTIOBankO(Module):
 
 
 class _RTIOBankI(Module):
-    def __init__(self, rbus, counter_width, fine_ts_width, fifo_depth):
+    def __init__(self, rbus, counter, fine_ts_width, fifo_depth):
+        counter_width = flen(counter)
         self.sel = Signal(max=len(rbus))
         self.timestamp = Signal(counter_width+fine_ts_width)
         self.value = Signal()
@@ -77,9 +75,6 @@ class _RTIOBankI(Module):
 
         # # #
 
-        counter = Signal(counter_width)
-        self.sync += counter.eq(counter + 1)
-
         timestamps = []
         values = []
         readables = []
@@ -143,17 +138,30 @@ class RTIO(Module, AutoCSR):
     def __init__(self, phy, clk_freq, counter_width=32, ofifo_depth=64, ififo_depth=64):
         fine_ts_width = get_fine_ts_width(phy.rbus)
 
+        # Counters
+        reset_counter = Signal()
+        o_counter = Signal(counter_width, reset=phy.loopback_latency)
+        i_counter = Signal(counter_width)
+        self.sync += \
+            If(reset_counter,
+                o_counter.eq(o_counter.reset),
+                i_counter.eq(i_counter.reset)
+            ).Else(
+                o_counter.eq(o_counter + 1),
+                i_counter.eq(i_counter + 1)
+            )
+
         # Submodules
         self.submodules.bank_o = InsertReset(_RTIOBankO(
             phy.rbus,
-            counter_width, fine_ts_width, ofifo_depth,
+            o_counter, fine_ts_width, ofifo_depth))
-            phy.loopback_latency))
         self.submodules.bank_i = InsertReset(_RTIOBankI(
             phy.rbus,
-            counter_width, fine_ts_width, ofifo_depth))
+            i_counter, fine_ts_width, ofifo_depth))
 
         # CSRs
-        self._r_reset = CSRStorage(reset=1)
+        self._r_reset_logic = CSRStorage(reset=1)
+        self._r_reset_counter = CSRStorage(reset=1)
         self._r_chan_sel = CSRStorage(flen(self.bank_o.sel))
 
         self._r_oe = CSR()
@@ -194,7 +202,7 @@ class RTIO(Module, AutoCSR):
 
         # Output/Gate
         self.comb += [
-            self.bank_o.reset.eq(self._r_reset.storage),
+            self.bank_o.reset.eq(self._r_reset_logic.storage),
             self.bank_o.sel.eq(self._r_chan_sel.storage),
             self.bank_o.timestamp.eq(self._r_o_timestamp.storage),
             self.bank_o.value.eq(self._r_o_value.storage),
@@ -207,7 +215,7 @@ class RTIO(Module, AutoCSR):
 
         # Input
         self.comb += [
-            self.bank_i.reset.eq(self._r_reset.storage),
+            self.bank_i.reset.eq(self._r_reset_logic.storage),
             self.bank_i.sel.eq(self._r_chan_sel.storage),
             self._r_i_timestamp.status.eq(self.bank_i.timestamp),
             self._r_i_value.status.eq(self.bank_i.value),
@@ -217,11 +225,12 @@ class RTIO(Module, AutoCSR):
                 Cat(self.bank_i.overflow, self.bank_i.pileup))
         ]
 
-        # Counter
+        # Counter access
+        self.comb += reset_counter.eq(self._r_reset_counter.storage)
         self.sync += \
            If(self._r_counter_update.re,
                self._r_counter.status.eq(Cat(Replicate(0, fine_ts_width),
-                                             self.bank_o.counter))
+                                             o_counter))
            )
 
         # Frequency

soc/runtime/dds.c

@@ -31,10 +31,10 @@ static void fud(long long int fud_time)
     long long int fud_end_time;
     static long long int previous_fud_end_time;
 
-    r = rtio_reset_read();
+    r = rtio_reset_counter_read();
     if(r)
         previous_fud_end_time = 0;
-    rtio_reset_write(0);
+    rtio_reset_counter_write(0);
 
     rtio_chan_sel_write(RTIO_FUD_CHANNEL);
     if(fud_time < 0) {
@@ -52,12 +52,15 @@ static void fud(long long int fud_time)
     rtio_o_timestamp_write(fud_end_time);
     rtio_o_value_write(0);
     rtio_o_we_write(1);
-    if(rtio_o_error_read())
+    if(rtio_o_error_read()) {
+        rtio_reset_logic_write(1);
+        rtio_reset_logic_write(0);
         exception_raise(EID_RTIO_UNDERFLOW);
+    }
 
     if(r) {
         fud_sync();
-        rtio_reset_write(1);
+        rtio_reset_counter_write(1);
     }
 }
 

soc/runtime/main.c

@@ -110,6 +110,7 @@ int main(void)
     uart_init();
 
     puts("ARTIQ runtime built "__DATE__" "__TIME__"\n");
+    rtio_init();
     dds_init();
     blink_led();
     corecom_serve(load_object, run_kernel);

soc/runtime/rtio.c

@@ -5,7 +5,9 @@
 
 void rtio_init(void)
 {
-    rtio_reset_write(1);
+    rtio_reset_counter_write(1);
+    rtio_reset_logic_write(1);
+    rtio_reset_logic_write(0);
 }
 
 void rtio_oe(int channel, int oe)
@@ -16,15 +18,18 @@ void rtio_oe(int channel, int oe)
 
 void rtio_set(long long int timestamp, int channel, int value)
 {
-    rtio_reset_write(0);
+    rtio_reset_counter_write(0);
     rtio_chan_sel_write(channel);
     rtio_o_timestamp_write(timestamp);
     rtio_o_value_write(value);
     while(!rtio_o_writable_read());
     rtio_o_we_write(1);
-    if(rtio_o_error_read())
+    if(rtio_o_error_read()) {
+        rtio_reset_logic_write(1);
+        rtio_reset_logic_write(0);
         exception_raise(EID_RTIO_UNDERFLOW);
     }
+}
 
 void rtio_replace(long long int timestamp, int channel, int value)
 {
@@ -32,9 +37,12 @@ void rtio_replace(long long int timestamp, int channel, int value)
     rtio_o_timestamp_write(timestamp);
     rtio_o_value_write(value);
     rtio_o_replace_write(1);
-    if(rtio_o_error_read())
+    if(rtio_o_error_read()) {
+        rtio_reset_logic_write(1);
+        rtio_reset_logic_write(0);
         exception_raise(EID_RTIO_UNDERFLOW);
     }
+}
 
 void rtio_sync(int channel)
 {