Merge instruction and data bus abstractions

This commit is contained in:
Donald Sebastian Leung 2020-08-25 10:12:02 +08:00
parent ca135d024f
commit ac7991ae86
3 changed files with 17 additions and 66 deletions

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@ -1,45 +0,0 @@
from nmigen import *
"""
Instruction Bus (Wishbone Slave)
"""
# TODO: Perhaps axiomatize a read-only instruction store where the
# instruction bus reads from when requested by the CPU core?
class InstructionBus(Elaboratable):
def __init__(self):
self.adr = Signal(30)
self.dat_w = Signal(32)
self.dat_r = Signal(32)
self.sel = Signal(4)
self.cyc = Signal(1)
self.stb = Signal(1)
self.ack = Signal(1)
self.we = Signal(1)
self.cti = Signal(3)
self.bte = Signal(2)
self.err = Signal(1)
def ports(self):
input_ports = [
self.adr,
self.dat_w,
self.sel,
self.cyc,
self.stb,
self.we,
self.cti,
self.bte
]
output_ports = [
self.dat_r,
self.ack,
self.err
]
return input_ports + output_ports
def elaborate(self, platform):
m = Module()
# TODO
return m

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@ -1,13 +1,10 @@
from nmigen import *
"""
Data Bus (Wishbone Slave)
Memory Bus (Wishbone Slave)
"""
# TODO: Perhaps axiomatize a read-write data store where the
# data bus reads from / writes to when requested by the CPU core?
class DataBus(Elaboratable):
class MemoryBus(Elaboratable):
def __init__(self):
self.adr = Signal(30)
self.dat_w = Signal(32)

View File

@ -8,8 +8,7 @@ from ...checks.liveness_check import *
from ...checks.unique_check import *
from minerva.core import *
from ...insns.isa_rv32i import *
from .ibus import *
from .dbus import *
from .memory_bus import *
from collections import namedtuple
RISCVFormalParameters = namedtuple('RISCVFormalParameters',
@ -29,7 +28,7 @@ class InsnSpec(Elaboratable):
rvformal_addr_valid=lambda x:Const(1))
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -42,7 +41,7 @@ class InsnSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)
@ -100,7 +99,7 @@ class PcFwdSpec(Elaboratable):
rvformal_addr_valid=lambda x:Const(1))
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -113,7 +112,7 @@ class PcFwdSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)
@ -154,7 +153,7 @@ class PcBwdSpec(Elaboratable):
rvformal_addr_valid=lambda x:Const(1))
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -167,7 +166,7 @@ class PcBwdSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)
@ -206,7 +205,7 @@ class RegSpec(Elaboratable):
m.submodules.reg_spec = reg_spec = RegCheck(params=RISCVFormalParameters(32, 32, False, False, False))
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -219,7 +218,7 @@ class RegSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)
@ -261,7 +260,7 @@ class CausalSpec(Elaboratable):
m.submodules.causal_spec = causal_spec = CausalCheck()
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -274,7 +273,7 @@ class CausalSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)
@ -313,7 +312,7 @@ class LivenessSpec(Elaboratable):
m.submodules.liveness_spec = liveness_spec = LivenessCheck()
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -326,7 +325,7 @@ class LivenessSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)
@ -364,7 +363,7 @@ class UniqueSpec(Elaboratable):
m.submodules.unique_spec = unique_spec = UniqueCheck()
# Connect Wishbone instruction bus to Minerva CPU
m.submodules.ibus = ibus = InstructionBus()
m.submodules.ibus = ibus = MemoryBus()
m.d.comb += ibus.adr.eq(cpu.ibus.adr)
m.d.comb += ibus.dat_w.eq(cpu.ibus.dat_w)
m.d.comb += cpu.ibus.dat_r.eq(ibus.dat_r)
@ -377,7 +376,7 @@ class UniqueSpec(Elaboratable):
m.d.comb += ibus.bte.eq(cpu.ibus.bte)
m.d.comb += cpu.ibus.err.eq(ibus.err)
# Connect Wishbone data bus to Minerva CPU
m.submodules.dbus = dbus = DataBus()
m.submodules.dbus = dbus = MemoryBus()
m.d.comb += dbus.adr.eq(cpu.dbus.adr)
m.d.comb += dbus.dat_w.eq(cpu.dbus.dat_w)
m.d.comb += cpu.dbus.dat_r.eq(dbus.dat_r)