memtest: add DMA cores

diff --git a/milkymist/memtest/__init__.py b/milkymist/memtest/__init__.py
index dcc05f8a2bfba037c5bb51c06e20ebfc64b87b3f..7434cd55dd7e9e16cf2ee432a5525f8a8604e4d3 100644 (file)
--- a/milkymist/memtest/__init__.py
+++ b/milkymist/memtest/__init__.py
@@ -1,10 +1,13 @@
 from migen.fhdl.std import *
 from migen.genlib.misc import optree
-from migen.fhdl import verilog
+from migen.bank.description import *
+from migen.actorlib import dma_lasmi
+from migen.actorlib.spi import MODE_SINGLE_SHOT, DMAReadController, DMAWriteController
 
 class LFSR(Module):
        def __init__(self, n_out, n_state=31, taps=[27, 30]):
                self.ce = Signal()
+               self.reset = Signal()
                self.o = Signal(n_out)
 
                ###
@@ -17,12 +20,16 @@ class LFSR(Module):
                        curval.insert(0, nv)
                        curval.pop()
 
-               self.sync += If(self.ce,
+               self.sync += If(self.reset,
+                               state.eq(0),
+                               self.o.eq(0)
+                       ).Elif(self.ce,
                                state.eq(Cat(*curval[:n_state])),
                                self.o.eq(Cat(*curval))
                        )
 
 def _print_lfsr_code():
+       from migen.fhdl import verilog
        dut = LFSR(3, 4, [3, 2])
        print(verilog.convert(dut, ios={dut.ce, dut.o}))
 
@@ -40,6 +47,62 @@ def _sim_lfsr():
        sim = Simulator(tb)
        sim.run(20)
 
+memtest_magic = 0x361f
+
+class MemtestWriter(Module):
+       def __init__(self, lasmim):
+               self._r_magic = CSRStatus(16)
+               self._r_reset = CSR()
+               self.submodules._dma = DMAWriteController(dma_lasmi.Writer(lasmim), MODE_SINGLE_SHOT)
+
+               ###
+
+               self.comb += self._r_magic.status.eq(memtest_magic)
+
+               lfsr = LFSR(lasmim.dw)
+               self.submodules += lfsr
+               self.comb += lfsr.reset.eq(self._r_reset.re)
+
+               self.comb += [
+                       self._dma.data.stb.eq(1),
+                       lfsr.ce.eq(self._dma.data.ack),
+                       self._dma.data.payload.d.eq(lfsr.o)
+               ]
+
+       def get_csrs(self):
+               return [self._r_magic, self._r_reset] + self._dma.get_csrs()
+
+class MemtestReader(Module):
+       def __init__(self, lasmim):
+               self._r_magic = CSRStatus(16)
+               self._r_reset = CSR()
+               self._r_error_count = CSRStatus(lasmim.aw)
+               self.submodules._dma = DMAReadController(dma_lasmi.Reader(lasmim), MODE_SINGLE_SHOT)
+
+               ###
+
+               self.comb += self._r_magic.status.eq(memtest_magic)
+
+               lfsr = LFSR(lasmim.dw)
+               self.submodules += lfsr
+               self.comb += lfsr.reset.eq(self._r_reset.re)
+
+               self.comb += [
+                       lfsr.ce.eq(self._dma.data.stb),
+                       self._dma.data.ack.eq(1)
+               ]
+               err_cnt = self._r_error_count.status
+               self.sync += [
+                       If(self._r_reset.re,
+                               err_cnt.eq(0)
+                       ).Elif(self._dma.data.stb,
+                               If(self._dma.data.payload.d != lfsr.o, err_cnt.eq(err_cnt + 1))
+                       )
+               ]
+
+       def get_csrs(self):
+               return [self._r_magic, self._r_reset, self._r_error_count] + self._dma.get_csrs()
+
 if __name__ == "__main__":
        _print_lfsr_code()
        _sim_lfsr()