dma: set conversion granularity using bus width

artiq/gateware/rtio/analyzer.py

@@ -3,6 +3,7 @@ from migen.genlib.record import Record, layout_len
 from misoc.interconnect.csr import *
 from misoc.interconnect import stream
 
+from artiq.gateware.rtio import dma
 from artiq.gateware.rtio.cri import commands as cri_commands
 from artiq.coredevice.comm_analyzer import MessageType, ExceptionType
 
@@ -42,20 +43,6 @@ assert layout_len(exception_layout) == message_len
 assert layout_len(stopped_layout) == message_len
 
 
-def convert_signal(signal):
-    assert len(signal) % 8 == 0
-    nbytes = len(signal)//8
-    assert nbytes % 4 == 0
-    nwords = nbytes//4
-    signal_words = []
-    for i in range(nwords):
-        signal_bytes = []
-        for j in range(4):
-            signal_bytes.append(signal[8*(j+i*4):8*((j+i*4)+1)])
-        signal_words.extend(reversed(signal_bytes))
-    return Cat(*signal_words)
-
-
 class MessageEncoder(Module, AutoCSR):
     def __init__(self, tsc, cri, enable):
         self.source = stream.Endpoint([("data", message_len)])
@@ -150,7 +137,7 @@ class MessageEncoder(Module, AutoCSR):
 
 
 class DMAWriter(Module, AutoCSR):
-    def __init__(self, membus):
+    def __init__(self, membus, cpu_dw):
         aw = len(membus.adr)
         dw = len(membus.dat_w)
         messages_per_dw = dw//message_len
@@ -175,7 +162,7 @@ class DMAWriter(Module, AutoCSR):
             membus.stb.eq(self.sink.stb),
             self.sink.ack.eq(membus.ack),
             membus.we.eq(1),
-            membus.dat_w.eq(convert_signal(self.sink.data))
+            membus.dat_w.eq(dma.convert_signal(self.sink.data, cpu_dw//8))
         ]
         if messages_per_dw > 1:
             for i in range(dw//8):
@@ -207,7 +194,7 @@ class DMAWriter(Module, AutoCSR):
 
 
 class Analyzer(Module, AutoCSR):
-    def __init__(self, tsc, cri, membus, fifo_depth=128):
+    def __init__(self, tsc, cri, membus, fifo_depth=128, cpu_dw=32):
         # shutdown procedure: set enable to 0, wait until busy=0
         self.enable = CSRStorage()
         self.busy = CSRStatus()
@@ -219,7 +206,7 @@ class Analyzer(Module, AutoCSR):
         self.submodules.converter = stream.Converter(
             message_len, len(membus.dat_w), reverse=True,
             report_valid_token_count=True)
-        self.submodules.dma = DMAWriter(membus)
+        self.submodules.dma = DMAWriter(membus, cpu_dw)
 
         enable_r = Signal()
         self.sync += [

artiq/gateware/rtio/dma.py

@@ -11,28 +11,20 @@ def _reverse_bytes(s, g):
     return Cat(reversed(list(s[i*g:(i+1)*g] for i in range(len(s)//g))))
 
 
-def reverse_bytes(s):
-    n = (len(s) + 7)//8
-    return Cat(*[s[i*8:min((i + 1)*8, len(s))]
-        for i in reversed(range(n))])
-
-
-def convert_signal(signal):
+def convert_signal(signal, granularity):
     assert len(signal) % 8 == 0
     nbytes = len(signal)//8
-    assert nbytes % 4 == 0
-    nwords = nbytes//4
+    assert nbytes % granularity == 0
+    nwords = nbytes//granularity
     signal_words = []
     for i in range(nwords):
-        signal_bytes = []
-        for j in range(4):
-            signal_bytes.append(signal[8*(j+i*4):8*((j+i*4)+1)])
-        signal_words.extend(reversed(signal_bytes))
-    return Cat(*signal_words)
+        signal_words.append(_reverse_bytes(
+                signal[i*granularity*8:(i+1)*granularity*8], 8))
+    return Cat(signal_words)
 
 
 class WishboneReader(Module):
-    def __init__(self, bus):
+    def __init__(self, bus, cpu_dw):
         self.bus = bus
 
         aw = len(bus.adr)
@@ -57,18 +49,18 @@ class WishboneReader(Module):
             If(self.source.ack, data_reg_loaded.eq(0)),
             If(bus.ack,
                 data_reg_loaded.eq(1),
-                self.source.data.eq(convert_signal(bus.dat_r)),
+                self.source.data.eq(convert_signal(bus.dat_r, cpu_dw//8)),
                 self.source.eop.eq(self.sink.eop)
             )
         ]
 
 
 class DMAReader(Module, AutoCSR):
-    def __init__(self, membus, enable):
+    def __init__(self, membus, enable, cpu_dw):
         aw = len(membus.adr)
         data_alignment = log2_int(len(membus.dat_w)//8)
 
-        self.submodules.wb_reader = WishboneReader(membus)
+        self.submodules.wb_reader = WishboneReader(membus, cpu_dw)
         self.source = self.wb_reader.source
 
         # All numbers in bytes
@@ -344,11 +336,11 @@ class CRIMaster(Module, AutoCSR):
 
 
 class DMA(Module):
-    def __init__(self, membus):
+    def __init__(self, membus, cpu_dw):
         self.enable = CSR()
 
         flow_enable = Signal()
-        self.submodules.dma = DMAReader(membus, flow_enable)
+        self.submodules.dma = DMAReader(membus, flow_enable, cpu_dw)
         self.submodules.slicer = RecordSlicer(len(membus.dat_w))
         self.submodules.time_offset = TimeOffset()
         self.submodules.cri_master = CRIMaster()