sawg: wire up all HBF outputs, latency compensation in phys, simplify

artiq/gateware/dsp/sawg.py

@@ -5,7 +5,7 @@ from misoc.interconnect.stream import Endpoint
 from misoc.cores.cordic import Cordic
 
 from .accu import PhasedAccu
-from .tools import eqh, Delay, SatAddMixin
+from .tools import eqh, SatAddMixin
 from .spline import Spline
 from .fir import ParallelHBFUpsampler, halfgen4_cascade
 
@@ -14,44 +14,10 @@ _Widths = namedtuple("_Widths", "t a p f")
 _Orders = namedtuple("_Orders", "a p f")
 
 
-class ParallelDDS(Module):
-    def __init__(self, widths, parallelism=1, a_delay=0):
-        self.i = Endpoint([("x", widths.a), ("y", widths.a),
-                           ("f", widths.f), ("p", widths.f), ("clr", 1)])
+class SplineParallelDUC(Module):
+    def __init__(self, widths, orders, parallelism=1, **kwargs):
         self.parallelism = parallelism
         self.widths = widths
-
-        ###
-
-        accu = PhasedAccu(widths.f, parallelism)
-        cordic = [Cordic(width=widths.a, widthz=widths.p, guard=None,
-                         eval_mode="pipelined") for i in range(parallelism)]
-        self.xo = [c.xo for c in cordic]
-        self.yo = [c.yo for c in cordic]
-        a_delay += accu.latency
-        xy_delay = Delay(2*widths.a, max(0, a_delay))
-        z_delay = Delay(parallelism*widths.p, max(0, -a_delay))
-        self.submodules += accu, xy_delay, z_delay, cordic
-        self.latency = max(0, a_delay) + cordic[0].latency
-        self.gain = cordic[0].gain
-
-        self.comb += [
-            xy_delay.i.eq(Cat(self.i.x, self.i.y)),
-            z_delay.i.eq(Cat(zi[-widths.p:]
-                             for zi in accu.o.payload.flatten())),
-            eqh(accu.i.p, self.i.p),
-            accu.i.f.eq(self.i.f),
-            accu.i.clr.eq(self.i.clr),
-            accu.i.stb.eq(self.i.stb),
-            self.i.ack.eq(accu.i.ack),
-            accu.o.ack.eq(1),
-            [Cat(c.xi, c.yi).eq(xy_delay.o) for c in cordic],
-            Cat(c.zi for c in cordic).eq(z_delay.o),
-        ]
-
-
-class SplineParallelDUC(ParallelDDS):
-    def __init__(self, widths, orders, **kwargs):
         p = Spline(order=orders.p, width=widths.p)
         f = Spline(order=orders.f, width=widths.f)
         self.f = f.tri(widths.t)
@@ -59,27 +25,41 @@ class SplineParallelDUC(ParallelDDS):
         self.submodules += p, f
         self.ce = Signal(reset=1)
         self.clr = Signal()
-        super().__init__(widths._replace(p=len(self.p.a0), f=len(self.f.a0)),
-                         **kwargs)
-        self.latency += f.latency
+
+        ###
+        accu = PhasedAccu(len(self.f.a0), parallelism)
+        cordic = [Cordic(width=widths.a, widthz=len(self.p.a0), guard=None,
+                         eval_mode="pipelined") for i in range(parallelism)]
+        self.submodules += accu, cordic
+
+        self.xi = [c.xi for c in cordic]
+        self.yi = [c.yi for c in cordic]
+        self.xo = [c.xo for c in cordic]
+        self.yo = [c.yo for c in cordic]
+        self.latency = cordic[0].latency
+        self.gain = cordic[0].gain
+        self.f.latency += accu.latency + self.latency
+        self.p.latency += accu.latency + self.latency
 
         ###
 
         assert p.latency == f.latency
-
         self.comb += [
             p.o.ack.eq(self.ce),
             f.o.ack.eq(self.ce),
-            eqh(self.i.f, f.o.a0),
-            eqh(self.i.p, p.o.a0),
-            self.i.stb.eq(p.o.stb | f.o.stb),
+            eqh(accu.i.f, f.o.a0),
+            eqh(accu.i.p, p.o.a0),
+            accu.i.stb.eq(p.o.stb | f.o.stb),
+            accu.o.ack.eq(1),
+            [eqh(c.zi, zi) for c, zi in
+             zip(cordic, accu.o.payload.flatten())]
         ]
 
         assert p.latency == 1
         self.sync += [
-            self.i.clr.eq(0),
+            accu.i.clr.eq(0),
             If(p.i.stb,
-                self.i.clr.eq(self.clr),
+                accu.i.clr.eq(self.clr),
             ),
         ]
 
@@ -91,12 +71,14 @@ class SplineParallelDDS(SplineParallelDUC):
         self.submodules += a
         super().__init__(widths._replace(a=len(self.a.a0)), orders, **kwargs)
 
+        self.a.latency += self.latency
+
         ###
 
         self.comb += [
             a.o.ack.eq(self.ce),
-            eqh(self.i.x, a.o.a0),
-            self.i.y.eq(0),
+            [eqh(x, a.o.a0) for x in self.xi],
+            [y.eq(0) for y in self.yi],
         ]
 
 
@@ -151,12 +133,11 @@ class Channel(Module, SatAddMixin):
         hbf = [ParallelHBFUpsampler(coeff, width=width, shift=17)
                for i in range(2)]
         self.submodules.b = b = SplineParallelDUC(
-            widths._replace(a=len(a1.xo[0]), f=widths.f - width), orders,
-            parallelism=parallelism, a_delay=-a1.latency-hbf[0].latency)
+            widths._replace(a=len(hbf[0].o[0]), f=widths.f - width), orders,
+            parallelism=parallelism)
         cfg = Config(widths.a)
         u = Spline(width=widths.a, order=orders.a)
-        du = Delay(width, a1.latency + hbf[0].latency + b.latency - u.latency)
-        self.submodules += cfg, u, du, hbf
+        self.submodules += cfg, u, hbf
         self.u = u.tri(widths.t)
         self.i = [cfg.i, self.u, a1.a, a1.f, a1.p, a2.a, a2.f, a2.p, b.f, b.p]
         self.i_names = "cfg u a1 f1 p1 a2 f2 p2 f0 p0".split()
@@ -166,9 +147,23 @@ class Channel(Module, SatAddMixin):
         self.widths = widths
         self.orders = orders
         self.parallelism = parallelism
-        self.latency = a1.latency + hbf[0].latency + b.latency + 2
         self.cordic_gain = a1.gain*b.gain
 
+        self.u.latency += 1
+        b.p.latency += 2
+        b.f.latency += 2
+        a_latency_delta = hbf[0].latency + b.latency + 2
+        for a in a1, a2:
+            a.a.latency += a_latency_delta
+            a.p.latency += a_latency_delta
+            a.f.latency += a_latency_delta
+
+        self.latency = max(_.latency for _ in self.i[1:])
+        for i in self.i[1:]:
+            i.latency -= self.latency
+            assert i.latency <= 0
+        cfg.i.latency = 0
+
         ###
 
         self.comb += [
@@ -177,8 +172,8 @@ class Channel(Module, SatAddMixin):
             b.ce.eq(cfg.ce),
             u.o.ack.eq(cfg.ce),
             Cat(a1.clr, a2.clr, b.clr).eq(cfg.clr),
-            b.i.x.eq(hbf[0].o[0]),  # FIXME: rip up
-            b.i.y.eq(hbf[1].o[0]),
+            Cat(b.xi).eq(Cat(hbf[0].o)),
+            Cat(b.yi).eq(Cat(hbf[1].o)),
         ]
         self.sync += [
             hbf[0].i.eq(self.sat_add(a1.xo[0], a2.xo[0],
@@ -187,14 +182,16 @@ class Channel(Module, SatAddMixin):
             hbf[1].i.eq(self.sat_add(a1.yo[0], a2.yo[0],
                                      limits=cfg.limits[1],
                                      clipped=cfg.clipped[1])),
-            eqh(du.i, u.o.a0),
         ]
         # wire up outputs and q_{i,o} exchange
         for o, x, y in zip(self.o, b.xo, self.y_in):
             self.sync += [
                 o.eq(self.sat_add(
-                    du.o, Mux(cfg.iq_en[0], x, 0), Mux(cfg.iq_en[1], y, 0),
-                    limits=cfg.limits[2], clipped=cfg.clipped[2])),
+                    u.o.a0[-len(o):],
+                    Mux(cfg.iq_en[0], x, 0),
+                    Mux(cfg.iq_en[1], y, 0),
+                    limits=cfg.limits[2],
+                    clipped=cfg.clipped[2])),
             ]
 
     def connect_y(self, buddy):

artiq/gateware/dsp/spline.py

@@ -37,6 +37,7 @@ class Spline(Module):
                   enumerate(self.i.payload.layout[::-1])]
         layout.reverse()
         i = Endpoint(layout)
+        i.latency = self.latency
         self.comb += [
             self.i.stb.eq(i.stb),
             i.ack.eq(self.i.ack),

artiq/gateware/rtio/phy/sawg.py

@@ -16,7 +16,8 @@ class Channel(_ChannelPHY):
         _ChannelPHY.__init__(self, *args, **kwargs)
         self.phys = []
         for i in self.i:
-            rl = rtlink.Interface(rtlink.OInterface(len(i.payload)))
+            rl = rtlink.Interface(rtlink.OInterface(len(i.payload),
+                                                    delay=-i.latency))
             self.comb += [
                 i.stb.eq(rl.o.stb),
                 rl.o.busy.eq(~i.ack),