From e43684a3ed988991cf0456164fa141216ee4ee27 Mon Sep 17 00:00:00 2001
From: mwojcik <mw@m-labs.hk>
Date: Wed, 18 Aug 2021 12:36:17 +0200
Subject: [PATCH] moved AXI SRAM to migen-axi

---
 src/gateware/aux_controller.py | 158 +--------------------------------
 1 file changed, 4 insertions(+), 154 deletions(-)

diff --git a/src/gateware/aux_controller.py b/src/gateware/aux_controller.py
index 8f334a2..7b768fb 100644
--- a/src/gateware/aux_controller.py
+++ b/src/gateware/aux_controller.py
@@ -1,163 +1,13 @@
 """Auxiliary controller, common to satellite and master"""
 
-from operator import attrgetter
-
-from migen import *
-from migen.fhdl.simplify import FullMemoryWE
-
-from misoc.interconnect.csr import *
-from migen_axi.interconnect import axi
 from artiq.gateware.drtio.aux_controller import Transmitter, Receiver
+from migen.fhdl.simplify import FullMemoryWE
+from misoc.interconnect.csr import *
+from migen_axi.interconnect.sram import SRAM
+from migen_axi.interconnect import axi
 
 max_packet = 1024
 
-OUT_BURST_LEN = 10
-IN_BURST_LEN = 4
-
-class SRAM(Module):
-    def __init__(self, mem_or_size, read_only=False, init=None, bus=None):
-
-        # SRAM initialisation
-
-        if bus is None:
-            bus = axi.Interface()
-        self.bus = bus
-        bus_data_width = len(self.bus.r.data)
-        if isinstance(mem_or_size, Memory):
-            assert(mem_or_size.width <= bus_data_width)
-            self.mem = mem_or_size
-        else:
-            self.mem = Memory(bus_data_width, mem_or_size//(bus_data_width//8), init=init)
-
-        # memory
-        port = self.mem.get_port(write_capable=not read_only, we_granularity=8)
-        self.specials += self.mem, port
-
-        ###
-
-        ar, aw, w, r, b = attrgetter("ar", "aw", "w", "r", "b")(bus)
-
-        # Dout : Data received from CPU, output by SRAM <- port.dat_r
-        # Din : Data driven into SRAM, written into CPU <- port.dat_w
-        self.dout_index = Signal.like(ar.len)
-
-        self.r_addr_incr = axi.Incr(ar)
-        self.w_addr_incr = axi.Incr(aw)
-
-        ### Read
-
-        self.comb += [
-            r.data.eq(port.dat_r),
-            port.adr.eq(self.r_addr_incr.addr)
-        ]
-
-        # read control
-        self.submodules.read_fsm = read_fsm = FSM(reset_state="IDLE")
-        read_fsm.act("IDLE",
-            If(ar.valid,
-                port.adr.eq(self.r_addr_incr.addr),
-                ar.ready.eq(1),
-                NextState("READ_START"),
-            )
-        )
-        read_fsm.act("READ_START",
-            r.resp.eq(axi.Response.okay.value),
-            r.valid.eq(1),
-            If(r.ready,
-                NextState("READ"))
-        )
-        read_fsm.act("READ",
-            If(r.last & r.ready, # that's a smart way of skipping "LAST" state    
-                NextState("IDLE")
-            )
-        )
-
-        self.sync += [
-            If(read_fsm.ongoing("IDLE"),
-                self.dout_index.eq(0),
-                r.valid.eq(0),  # shall it be reset too on IDLE?
-                ar.ready.eq(0),
-                r.last.eq(0)
-            ).Else(If(r.ready & read_fsm.ongoing("READ"),
-                    self.dout_index.eq(self.dout_index+1),
-                    If(self.dout_index==ar.len, r.last.eq(1)) # and update last
-                )
-            )
-        ]
-
-        ### Write
-
-        if not read_only:
-            self.comb += [
-                port.dat_w.eq(w.data),
-                port.adr.eq(self.w_addr_incr.addr),
-            ]
-
-            self.submodules.write_fsm = write_fsm = FSM(reset_state="IDLE")
-            write_fsm.act("IDLE",
-                w.ready.eq(0),
-                aw.ready.eq(0),
-                b.valid.eq(0),
-                If(aw.valid,
-                    NextState("AW_VALID_WAIT")
-                )
-            )
-            write_fsm.act("AW_VALID_WAIT",  # wait for data
-                aw.ready.eq(1),
-                If(w.valid,
-                    NextState("WRITE"),
-                )
-            )
-            # write_fsm.act("DATA_WAIT",
-            #     aw.valid.eq(0),
-            #     If(self.din_ready,
-            #         w.valid.eq(1),
-            #         NextState("WRITE")
-            #     )
-            # )
-            write_fsm.act("WRITE",
-                w.ready.eq(1),
-                If(w.ready & w.last,
-                    NextState("WRITE_RESP")
-                )
-            )
-
-            write_fsm.act("WRITE_RESP",
-                port.we.eq(0),
-                b.resp.eq(axi.Response.okay.value),
-                b.valid.eq(1),
-                If(b.ready,
-                    NextState("IDLE")
-                )
-            )
-
-            self.sync += If(w.ready & w.valid, port.we.eq(1))
-
-            # self.sync += [
-            #     If(write_fsm.ongoing("IDLE"),
-            #         self.din_index.eq(0) 
-            #     ), # but need to synchronise the address too)
-            # ]
-
-
-        # # generate write enable signal
-        # if not read_only:
-        #     #                          replace with?      stb -> w.strb    we->w.ready?     sel[i]-> r.valid
-        #     self.comb += [port.we[i].eq(self.bus.cyc & self.bus.w.strb & self.bus.w.ready & self.bus.r.valid)
-        #         for i in range(4)]
-        # # address and data
-        # self.comb += [
-        #     self.bus.r.ready.eq(self.bus.r.valid), # AXI handshake?
-        #     port.adr.eq(self.bus.ar.addr[:len(port.adr)]),
-        #     self.bus.r.data.eq(port.dat_r)
-        # ]
-        # if not read_only:
-        #     self.comb += port.dat_w.eq(self.bus.w.data),
-        # # generate ack
-        # self.sync += [
-        #     self.bus.ack.eq(0),
-        #     If(self.bus.cyc & self.bus.stb & ~self.bus.ack, self.bus.ack.eq(1))
-        # ]
 
 # TODO: FullMemoryWE should be applied by migen.build
 @FullMemoryWE()