From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Tue, 15 Sep 2020 11:52:04 +0000 (+0100)
Subject: add in MMU and DCache into MMU FSM
X-Git-Tag: semi_working_ecp5~29
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=f6836bd7121e130c846c1e434c00b8685b43311a;p=soc.git

add in MMU and DCache into MMU FSM
---

diff --git a/src/soc/fu/mmu/fsm.py b/src/soc/fu/mmu/fsm.py
index c7e73fbd..0474d33c 100644
--- a/src/soc/fu/mmu/fsm.py
+++ b/src/soc/fu/mmu/fsm.py
@@ -2,6 +2,9 @@ from nmigen import Elaboratable, Module, Signal, Shape, unsigned, Cat, Mux
 from soc.fu.mmu.pipe_data import MMUInputData, MMUOutputData, MMUPipeSpec
 from nmutil.singlepipe import ControlBase
 
+from soc.experiment.mmu import MMU
+from soc.experiment.dcache import DCache
+
 
 class FSMMMUStage(ControlBase):
     def __init__(self, pspec):
@@ -11,8 +14,24 @@ class FSMMMUStage(ControlBase):
         self.p.data_i = MMUInputData(pspec)
         self.n.data_o = MMUOutputData(pspec)
 
+        # this Function Unit is extremely unusual in that it actually stores a
+        # "thing" rather than "processes inputs and produces outputs".  hence
+        # why it has to be a FSM.  linking up LD/ST however is going to have
+        # to be done back in Issuer (or Core)
+
+        self.mmu = MMU()
+        self.dcache = DCache()
+
+
     def elaborate(self, platform):
         m = super().elaborate(platform)
+
+        # link mmu and dcache together
+        m.submodules.dcache = dcache = self.dcache
+        m.submodules.mmu = mmu = self.mmu
+        m.d.comb += dcache.m_in.eq(mmu.d_out)
+        m.d.comb += mmu.d_in.eq(dcache.m_out)
+
         data_i = self.p.data_i
         data_o = self.n.data_o