From 0b08c83f38c2fd4d2c81220311bc942903c57085 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Mon, 14 Sep 2020 10:58:02 +0100
Subject: [PATCH] add mmu-dcache test

---
 src/soc/experiment/test/test_mmu_dcache.py | 129 +++++++++++++++++++++
 1 file changed, 129 insertions(+)
 create mode 100644 src/soc/experiment/test/test_mmu_dcache.py

diff --git a/src/soc/experiment/test/test_mmu_dcache.py b/src/soc/experiment/test/test_mmu_dcache.py
new file mode 100644
index 00000000..6efd8f88
--- /dev/null
+++ b/src/soc/experiment/test/test_mmu_dcache.py
@@ -0,0 +1,129 @@
+from nmigen import (C, Module, Signal, Elaboratable, Mux, Cat, Repl, Signal)
+from nmigen.cli import main
+from nmigen.cli import rtlil
+from nmutil.iocontrol import RecordObject
+from nmutil.byterev import byte_reverse
+from nmutil.mask import Mask, masked
+from nmutil.util import Display
+
+if True:
+    from nmigen.back.pysim import Simulator, Delay, Settle
+else:
+    from nmigen.sim.cxxsim import Simulator, Delay, Settle
+from nmutil.util import wrap
+
+from soc.experiment.mem_types import (LoadStore1ToMMUType,
+                                 MMUToLoadStore1Type,
+                                 MMUToDCacheType,
+                                 DCacheToMMUType,
+                                 MMUToICacheType)
+
+from soc.experiment.mmu import MMU
+from soc.experiment.dcache import DCache
+
+stop = False
+
+
+def wb_get(dc):
+    """simulator process for getting memory load requests
+    """
+
+    global stop
+
+    def b(x):
+        return int.from_bytes(x.to_bytes(8, byteorder='little'),
+                              byteorder='big', signed=False)
+
+    mem = {0x10000:    # PARTITION_TABLE_2
+                       # PATB_GR=1 PRTB=0x1000 PRTS=0xb
+           b(0x800000000100000b),
+
+           0x30000:     # RADIX_ROOT_PTE
+                        # V = 1 L = 0 NLB = 0x400 NLS = 9
+           b(0x8000000000040009),
+
+           0x40000:     # RADIX_SECOND_LEVEL
+                        # 	   V = 1 L = 1 SW = 0 RPN = 0
+	                    # R = 1 C = 1 ATT = 0 EAA 0x7
+           b(0xc000000000000187),
+
+          0x1000000:   # PROCESS_TABLE_3
+                       # RTS1 = 0x2 RPDB = 0x300 RTS2 = 0x5 RPDS = 13
+           b(0x40000000000300ad),
+          }
+
+    while not stop:
+        while True: # wait for dc_valid
+            if stop:
+                return
+            cyc = yield (dc.wb_out.cyc)
+            stb = yield (dc.wb_out.stb)
+            if cyc and stb:
+                break
+            yield
+        addr = (yield dc.wb_out.adr) << 3
+        if addr not in mem:
+            print ("    DCACHE LOOKUP FAIL %x" % (addr))
+            stop = True
+            return
+
+        yield
+        data = mem[addr]
+        yield dc.wb_in.data.eq(data)
+        print ("dcache get %x data %x" % (addr, data))
+        yield dc.wb_in.ack.eq(1)
+        yield
+        yield dc.wb_in.ack.eq(0)
+
+
+def mmu_sim(mmu):
+    global stop
+    yield mmu.rin.prtbl.eq(0x1000000) # set process table
+    yield
+
+    yield mmu.l_in.load.eq(1)
+    yield mmu.l_in.priv.eq(1)
+    yield mmu.l_in.addr.eq(0x10000)
+    yield mmu.l_in.valid.eq(1)
+    while not stop: # wait for dc_valid / err
+        l_done = yield (mmu.l_out.done)
+        l_err = yield (mmu.l_out.err)
+        l_badtree = yield (mmu.l_out.badtree)
+        l_permerr = yield (mmu.l_out.perm_error)
+        l_rc_err = yield (mmu.l_out.rc_error)
+        l_segerr = yield (mmu.l_out.segerr)
+        l_invalid = yield (mmu.l_out.invalid)
+        if (l_done or l_err or l_badtree or
+            l_permerr or l_rc_err or l_segerr or l_invalid):
+            break
+        yield
+    addr = yield mmu.d_out.addr
+    pte = yield mmu.d_out.pte
+    print ("translated done %d err %d badtree %d addr %x pte %x" % \
+               (l_done, l_err, l_badtree, addr, pte))
+
+    stop = True
+
+
+def test_mmu():
+    mmu = MMU()
+    dcache = DCache()
+    m = Module()
+    m.submodules.mmu = mmu
+    m.submodules.dcache = dcache
+
+    # link mmu and dcache together
+    m.d.comb += dcache.m_in.eq(mmu.d_out)
+    m.d.comb += mmu.d_in.eq(dcache.m_out)
+
+    # nmigen Simulation
+    sim = Simulator(m)
+    sim.add_clock(1e-6)
+
+    sim.add_sync_process(wrap(mmu_sim(mmu)))
+    sim.add_sync_process(wrap(wb_get(dcache)))
+    with sim.write_vcd('test_mmu.vcd'):
+        sim.run()
+
+if __name__ == '__main__':
+    test_mmu()
-- 
2.30.2