def check(m: Module, data: Snapshot, alu: Signal):
m.d.comb += [
Assert(data.read_data[0].matches(MUL.opcode)),
]
for i in range(1, 10):
m.d.comb += [
Assert(Past(alu.oper, i) == Operation.MUL),
]
for i in range(3, 10):
m.d.comb += [
Assert(Past(alu.inputa, i) == data.pre.Y),
Assert(Past(alu.inputb, i) == data.pre.A),
]
m.d.comb += [
Assert(data.post.A == Past(alu.result, 1)),
Assert(data.post.X == data.pre.X),
Assert(data.post.Y == Past(alu.result, 2)),
Assert(data.post.SP == data.pre.SP),
Assert(data.post.PC == add16(data.pre.PC, 1)),
]
m.d.comb += [
Assert(data.addresses_read == 1),
Assert(data.addresses_written == 0),
Assert(data.read_addr[0] == add16(data.pre.PC, 0)),
]
def check(m: Module, data: Snapshot, alu: Signal):
m.d.comb += [
Assert(data.read_data[0].matches(JMP.opcode)),
]
m.d.comb += [
Assert(Past(alu.oper, 3) == Operation.NOP),
Assert(Past(alu.oper, 2) == Operation.NOP),
Assert(Past(alu.oper, 1) == Operation.NOP),
]
m.d.comb += [
Assert(data.post.A == data.pre.A),
Assert(data.post.X == data.pre.X),
Assert(data.post.Y == data.pre.Y),
Assert(data.post.SP == data.pre.SP),
Assert(data.post.PC[:8] == data.read_data[1]),
Assert(data.post.PC[8:] == data.read_data[2]),
Assert(data.post.PSW == data.pre.PSW),
]
m.d.comb += [
Assert(data.addresses_read == 3),
Assert(data.addresses_written == 0),
Assert(data.read_addr[0] == add16(data.pre.PC, 0)),
Assert(data.read_addr[1] == add16(data.pre.PC, 1)),
Assert(data.read_addr[2] == add16(data.pre.PC, 2)),
]
def __main():
m = top = Module()
clock = ClockInfo("i")
m.domains.i = clock.domain
top.submodules.regs = regs = RegisterFileModule(32)
regs.aux_ports.append(clock.clk)
regs.aux_ports.append(clock.rst)
comb = m.d.comb
with m.If(regs.rs1_in == 0):
comb += Assert(regs.rs1_out == 0)
with m.If(regs.rs2_in == 0):
comb += Assert(regs.rs2_out == 0)
with m.If(regs.rs2_in == regs.rs1_in):
comb += Assert(regs.rs2_out == regs.rs2_out)
with m.If((Past(regs.rd) == regs.rs1_in)
& (~Past(clock.rst) & (~clock.rst))):
with m.If(regs.rs1_in != 0):
comb += Assert(regs.rs1_out == Past(regs.rd_value))
nmigen_main(top, ports=regs.ports())
def formal(cls) -> Tuple[Module, List[Signal]]:
m = Module()
ph = ClockDomain("ph")
clk = ClockSignal("ph")
m.domains += ph
m.d.sync += clk.eq(~clk)
s = IC_7416374(clk="ph")
m.submodules += s
with m.If(s.n_oe):
m.d.comb += Assert(s.q == 0)
with m.If(~s.n_oe & Rose(clk)):
m.d.comb += Assert(s.q == Past(s.d))
with m.If(~s.n_oe & Fell(clk) & ~Past(s.n_oe)):
m.d.comb += Assert(s.q == Past(s.q))
sync_clk = ClockSignal("sync")
sync_rst = ResetSignal("sync")
# Make sure the clock is clocking
m.d.comb += Assume(sync_clk == ~Past(sync_clk))
# Don't want to test what happens when we reset.
m.d.comb += Assume(~sync_rst)
m.d.comb += Assume(~ResetSignal("ph"))
return m, [sync_clk, sync_rst, s.n_oe, s.q, s.d]
def past(self, signal):
return [
signal,
Past(signal),
Past(signal, 2),
Past(signal, 3),
Past(signal, 4),
]
def check(m: Module, data: Snapshot, alu: Signal):
m.d.comb += [
Assert(data.read_data[0].matches(MOV_A_read.opcode)),
]
m.d.comb += [
Assert(Past(alu.oper, 4) == Operation.NOP),
Assert(Past(alu.oper, 3) == Operation.NOP),
Assert(Past(alu.oper, 2) == Operation.NOP),
Assert(Past(alu.oper, 1) == Operation.OOR),
Assert(Past(alu.inputa) == data.read_data[3]),
Assert(Past(alu.inputb) == 0),
Assert(Past(alu.result) == data.read_data[3]),
]
m.d.comb += [
Assert(data.post.A == Past(alu.result)),
Assert(data.post.X == data.pre.X),
Assert(data.post.Y == data.pre.Y),
Assert(data.post.SP == data.pre.SP),
Assert(data.post.PC == add16(data.pre.PC, 3)),
]
m.d.comb += [
Assert(data.addresses_read == 4),
Assert(data.addresses_written == 0),
Assert(data.read_addr[0] == add16(data.pre.PC, 0)),
Assert(data.read_addr[1] == add16(data.pre.PC, 1)),
Assert(data.read_addr[2] == add16(data.pre.PC, 2)),
Assert(data.read_addr[3] == Cat(data.read_data[1], data.read_data[2])),
]
def verification_statements(m):
#Create Local Reference to the LDPC_Decoder
LDPC_Decoder = m.submodules.LDPC_Decoder
#Ensure that done and output signals are reset when start is toggled.
with m.If((LDPC_Decoder.start == 0) & Past(LDPC_Decoder.start)):
m.d.sync += Assert((LDPC_Decoder.done == 0))
m.d.sync += Assert((LDPC_Decoder.data_output == 0))
return
def elaborate(self, platform):
m = Module()
MAX_AMOUNT = Const(22)
with m.If(self.i_reset):
m.d.sync += self.counter.eq(0)
with m.Elif(self.i_start_signal & (self.counter == 0)):
m.d.sync += self.counter.eq(MAX_AMOUNT - 1)
with m.Elif(self.counter != 0):
m.d.sync += self.counter.eq(self.counter - 1)
m.d.sync += self.o_busy.eq((~self.i_reset) & \
((self.i_start_signal & (self.counter == 0)) | \
(self.counter > 1)))
if self.fv_mode:
f_past_valid = Signal(1, reset=0)
m.d.sync += f_past_valid.eq(1)
m.d.comb += Assert(self.counter < MAX_AMOUNT)
with m.If(f_past_valid & Past(self.i_start_signal)
& Past(self.o_busy)):
m.d.comb += Assume(self.i_start_signal)
with m.Elif(f_past_valid & Past(self.i_start_signal)
& ~Past(self.o_busy)):
m.d.comb += Assume(~self.i_start_signal)
m.d.comb += Assert(self.o_busy == (self.counter != 0))
with m.If(f_past_valid & Past(self.counter) != 0):
m.d.comb += Assert(self.counter < Past(self.counter))
return m
def formal(cls) -> Tuple[Module, List[Signal]]:
"""Formal verification for the Counter module."""
m = Module()
m.submodules.c = c = cls()
m.d.comb += Assert((c.count >= 1) & (c.count <= 999_999_999_999))
sync_clk = ClockSignal("sync")
sync_rst = ResetSignal("sync")
with m.If(Rose(sync_clk) & ~Initial()):
with m.If(c.count == 1):
m.d.comb += Assert(Past(c.count) == 999_999_999_999)
with m.Else():
m.d.comb += Assert(c.count == (Past(c.count) + 1))
# Make sure the clock is clocking
m.d.comb += Assume(sync_clk == ~Past(sync_clk))
# Don't want to test what happens when we reset.
m.d.comb += Assume(~sync_rst)
return m, [sync_clk, sync_rst]
def formal(cls) -> Tuple[Module, List[Signal]]:
"""Formal verification for the transparent latch.
Note that you MUST have multiclock on in the sby file, because there is
more than one clock in the system -- the default formal clock and the
local clock inside the transparent latch.
"""
m = Module()
m.submodules.latch = latch = TransparentLatch(32)
m.d.sync += Cover((latch.data_out == 0xAAAAAAAA) & (latch.le == 0)
& (Past(latch.data_out, 2) == 0xBBBBBBBB)
& (Past(latch.le, 2) == 0))
with m.If(latch.n_oe == 1):
m.d.comb += Assert(latch.data_out == 0)
with m.If((latch.n_oe == 0) & (latch.le == 1)):
m.d.comb += Assert(latch.data_out == latch.data_in)
with m.If((latch.n_oe == 0) & Fell(latch.le)):
m.d.sync += Assert(latch.data_out == Past(latch.data_in))
return m, [latch.data_in, latch.le, latch.n_oe]
def formal(cls) -> Tuple[Module, List[Signal]]:
m = Module()
ph = ClockDomain("ph")
clk = ClockSignal("ph")
m.domains += ph
m.d.sync += clk.eq(~clk)
s = IC_reg32_with_mux(clk="ph", N=2, faster=True)
m.submodules += s
sync_clk = ClockSignal("sync")
sync_rst = ResetSignal("sync")
with m.If(Rose(clk)):
with m.Switch(~Past(s.n_sel)):
with m.Case(0b11):
m.d.comb += Assert(0)
with m.Case(0b01):
m.d.comb += Assert(s.q == Past(s.d[0]))
with m.Case(0b10):
m.d.comb += Assert(s.q == Past(s.d[1]))
with m.Default():
m.d.comb += Assert(s.q == Past(s.q))
# Make sure the clock is clocking
m.d.comb += Assume(sync_clk == ~Past(sync_clk))
# Don't want to test what happens when we reset.
m.d.comb += Assume(~sync_rst)
m.d.comb += Assume(~ResetSignal("ph"))
m.d.comb += Assume(s.n_sel != 0)
return m, [sync_clk, sync_rst, s.d[0], s.d[1], s.n_sel, s.q]
def elaborate(self, platform):
m = Module()
# increments every clock cycle. when the high bit changes, the timers
# are decremented -> 256 cycle decrement period for them.
global_counter = Signal(9)
do_decrement = Signal()
m.d.sync += [
global_counter.eq(global_counter + 1),
do_decrement.eq(global_counter[-1] != Past(global_counter)[-1]),
]
# NOT arrays, we don't index them dynamically
timer_val = tuple(Signal(16) for _ in range(NUM_TIMERS))
timer_ended = tuple(Signal(1) for _ in range(NUM_TIMERS))
# decrement timers (before they potentially get written to)
for ti in range(NUM_TIMERS):
with m.If((timer_val[ti] > 0) & do_decrement):
m.d.sync += timer_val[ti].eq(timer_val[ti] - 1)
with m.If(timer_val[ti] == 1):
m.d.sync += timer_ended[ti].eq(1)
# let the timer values be set
with m.If(self.i_we):
with m.Switch(self.i_addr):
for ti in range(NUM_TIMERS):
with m.Case(ti):
m.d.sync += [
timer_val[ti].eq(self.i_wdata),
timer_ended[ti].eq(0),
]
with m.Case():
pass
# and let the end status be read
read_status = Signal() # bus expects one cycle of read latency
m.d.sync += self.o_rdata.eq(Cat(read_status, 0))
with m.If(self.i_re):
with m.Switch(self.i_addr):
for ti in range(NUM_TIMERS):
with m.Case(ti):
m.d.comb += read_status.eq(timer_ended[ti])
with m.Case():
pass
return m
def verification_statements(m):
#Create Local Reference to the LDPC_Encoder
LDPC_Encoder = m.submodules.LDPC_Encoder
#Ensure all codewords can be obtained
m.d.sync += Cover((LDPC_Encoder.data_output == 0b000000))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b011001))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b110010))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b101011))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b111100))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b100101))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b001110))
m.d.sync += Cover((LDPC_Encoder.data_output == 0b010111))
#Ensure invalid codewords cannot be obtained
m.d.sync += Cover((LDPC_Encoder.data_output != 0b111111))
#Ensure the correct codeword output is obtained for each input word.
m.d.sync += Cover((LDPC_Encoder.data_input == 0b000)
& (LDPC_Encoder.data_output == 0b000000))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b011)
& (LDPC_Encoder.data_output == 0b011001))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b110)
& (LDPC_Encoder.data_output == 0b110010))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b101)
& (LDPC_Encoder.data_output == 0b101011))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b111)
& (LDPC_Encoder.data_output == 0b111100))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b100)
& (LDPC_Encoder.data_output == 0b100101))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b001)
& (LDPC_Encoder.data_output == 0b001110))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b010)
& (LDPC_Encoder.data_output == 0b010111))
m.d.sync += Cover((LDPC_Encoder.data_input == 0b011)
& (LDPC_Encoder.data_output != 0b010111))
#Ensure that done and output signals are reset when start is toggled.
with m.If((LDPC_Encoder.start == 0) & Past(LDPC_Encoder.start)):
m.d.sync += Assert((LDPC_Encoder.done == 0))
m.d.sync += Assert((LDPC_Encoder.data_output == 0))
return
def formal(cls) -> Tuple[Module, List[Signal]]:
"""Formal verification for my module."""
m = Module()
m.submodules.my_class = my_class = cls()
sync_clk = ClockSignal("sync")
sync_rst = ResetSignal("sync")
# Make sure that the output is always the same as the input
m.d.comb += Assert(my_class.my_input == my_class.my_output)
# Cover the case where the output is 1.
m.d.comb += Cover(my_class.my_output == 1)
# Make sure the clock is clocking
m.d.comb += Assume(sync_clk == ~Past(sync_clk))
# Include this only if you don't want to test resets
m.d.comb += Assume(~sync_rst)
# Ensure sync's clock and reset signals are manipulable.
return m, [sync_clk, sync_rst, my_class.my_input]
def formal(cls) -> Tuple[Module, List[Signal]]:
"""Formal verification for the async memory.
Note that you MUST have multiclock on in the sby file, because there is
more than one clock in the system -- the default formal clock and the
local clock inside the memory.
"""
m = Module()
m.submodules.mem = mem = AsyncMemory(width=32, addr_lines=5)
# Assume "good practices":
# * n_oe and n_wr are never simultaneously 0, and any changes
# are separated by at least a cycle to allow buffers to turn off.
# * memory address remains stable throughout a write cycle, and
# is also stable just before a write cycle.
m.d.comb += Assume(mem.n_oe | mem.n_wr)
# Paren placement is very important! While Python logical operators
# and, or have lower precedence than ==, the bitwise operators
# &, |, ^ have *higher* precedence. It can be confusing when it looks
# like you're writing a boolean expression, but you're actually writing
# a bitwise expression.
with m.If(Fell(mem.n_oe)):
m.d.comb += Assume((mem.n_wr == 1) & (Past(mem.n_wr) == 1))
with m.If(Fell(mem.n_wr)):
m.d.comb += Assume((mem.n_oe == 1) & (Past(mem.n_oe) == 1))
with m.If(Rose(mem.n_wr) | (mem.n_wr == 0)):
m.d.comb += Assume(Stable(mem.addr))
m.d.comb += Cover((mem.data_out == 0xAAAAAAAA)
& (Past(mem.data_out) == 0xBBBBBBBB))
# Make sure that when the output is disabled, the output is zero, and
# when enabled, it's whatever we're pointing at in memory.
with m.If(mem.n_oe == 1):
m.d.comb += Assert(mem.data_out == 0)
with m.Else():
m.d.comb += Assert(mem.data_out == mem._mem[mem.addr])
# If we just wrote data, make sure that cell that we pointed at
# for writing now contains the data we wrote.
with m.If(Rose(mem.n_wr)):
m.d.comb += Assert(mem._mem[Past(mem.addr)] == Past(mem.data_in))
# Pick an address, any address.
check_addr = AnyConst(5)
# We assert that unless that address is written, its data will not
# change. To know when we've written the data, we have to create
# a clock domain to let us save the data when written.
saved_data_clk = ClockDomain("saved_data_clk")
m.domains.saved_data_clk = saved_data_clk
saved_data_clk.clk = mem.n_wr
saved_data = Signal(32)
with m.If(mem.addr == check_addr):
m.d.saved_data_clk += saved_data.eq(mem.data_in)
with m.If(Initial()):
m.d.comb += Assume(saved_data == mem._mem[check_addr])
m.d.comb += Assume(mem.n_wr == 1)
with m.Else():
m.d.comb += Assert(saved_data == mem._mem[check_addr])
return m, [mem.addr, mem.data_in, mem.n_wr, mem.n_oe]
def validate(self):
with self.is_running():
with self.is_instruction(0xC6, 2):
self.assert_equals(self.registers.b, Past(self.Din))
self.assert_end_of_instruction()
def elaborate(self, platform):
m = Module()
# hook up the modules which do the work
m.submodules.txm = txm = Transmitter(self.divisor)
m.submodules.rxm = rxm = Receiver(self.divisor)
m.d.comb += [
rxm.i_rx.eq(self.i_rx),
self.o_tx.eq(txm.o_tx),
]
# define the signals that make up the registers
r1_rx_error = SetReset(m, priority="set")
r1_tx_overflow = SetReset(m, priority="set")
r1_rx_timeout = SetReset(m, priority="set")
r1_rx_overflow = SetReset(m, priority="set")
r6_tx_full = SetReset(m, priority="set")
# hook up transmit "buffer". it's just one byte.
tx_data = Signal(8)
m.d.comb += [
txm.i_start_tx.eq(r6_tx_full.value),
txm.i_data.eq(tx_data),
r6_tx_full.reset.eq(txm.o_re),
]
# hook up receive FIFO. it's big so the CPU can be busy and not miss
# stuff
m.submodules.rx_fifo = rx_fifo = self.rx_fifo
m.d.comb += [
r1_rx_overflow.set.eq(~rx_fifo.w_rdy & rxm.o_we),
rx_fifo.w_data.eq(rxm.o_data),
rx_fifo.w_en.eq(rxm.o_we),
]
# hook up the CRC engine
m.submodules.crc = crc = KermitCRC()
# run the receive timeout timer
rt_timeout_val = Signal(16)
rt_timer_reset = SetReset(m, priority="set")
rt_timer_curr = Signal(16)
rt_subtimer = Signal(9)
# keep reset if reception is ongoing
with m.If(rxm.o_active):
m.d.comb += rt_timer_reset.set.eq(1)
# cancel reset request once it's been done
m.d.sync += rt_timer_reset.reset.eq(rt_timer_reset.value)
m.d.sync += rt_subtimer.eq(rt_subtimer - 1)
with m.If(rt_timer_reset.value):
m.d.sync += rt_timer_curr.eq(rt_timeout_val)
with m.Elif(rt_timer_curr > 0):
with m.If(
rt_subtimer[-1] != Past(rt_subtimer)[-1]): # rolled over?
m.d.sync += rt_timer_curr.eq(rt_timer_curr - 1)
# timeout about to hit zero?
m.d.comb += r1_rx_timeout.set.eq(rt_timer_curr == 1)
# handle the boneless bus.
read_data = Signal(16) # it expects one cycle of read latency
m.d.sync += self.o_rdata.eq(read_data)
with m.If(self.i_re):
with m.Switch(self.i_addr[:3]): # we only have 8 registers
with m.Case(0): # status register
m.d.comb += [
# transmitter remains active as long as there is data to
# transmit
read_data[15].eq(txm.o_active),
read_data[0].eq(rxm.o_active),
]
with m.Case(1): # error register
m.d.comb += [
read_data[15].eq(r1_rx_error.value),
read_data[2].eq(r1_tx_overflow.value),
read_data[1].eq(r1_rx_timeout.value),
read_data[0].eq(r1_rx_overflow.value),
]
with m.Case(2): # CRC value register
m.d.comb += read_data.eq(crc.o_crc)
with m.Case(4, 5): # rx status and receive data
# the FIFO will be okay if we read from it while empty, so
# we just read from it regardless
m.d.comb += rx_fifo.r_en.eq(1)
# can be read from low or high byte
with m.If(self.i_addr[0]): # high byte
m.d.comb += [
read_data[7:15].eq(rx_fifo.r_data),
read_data[15].eq(~rx_fifo.r_rdy),
]
with m.Else(): # low byte (rotated for status bit access)
m.d.comb += [
read_data[15].eq(rx_fifo.r_data[0]),
read_data[:7].eq(rx_fifo.r_data[1:]),
read_data[14].eq(~rx_fifo.r_rdy),
]
# if there actually was a byte, fold it into the CRC
with m.If(rx_fifo.r_rdy):
m.d.comb += [
crc.i_byte.eq(rx_fifo.r_data),
crc.i_start.eq(1),
]
with m.Case(6, 7): # tx fifo status
m.d.comb += read_data[0].eq(r6_tx_full.value)
with m.Elif(self.i_we):
with m.Switch(self.i_addr[:3]):
with m.Case(1): # error register
m.d.comb += [
r1_rx_error.reset.eq(self.i_wdata[15]),
r1_tx_overflow.reset.eq(self.i_wdata[2]),
r1_rx_timeout.reset.eq(self.i_wdata[1]),
r1_rx_overflow.reset.eq(self.i_wdata[0]),
]
with m.If(self.i_wdata[1]):
m.d.comb += rt_timer_reset.set.eq(1)
with m.Case(2): # CRC reset register
m.d.comb += crc.i_reset.eq(1)
with m.Case(3): # receive timeout register
m.d.sync += rt_timeout_val.eq(self.i_wdata)
m.d.comb += rt_timer_reset.set.eq(1)
with m.Case(6, 7): # transmit data register
# can be written to low or high byte
value = Signal(8)
m.d.comb += value.eq(
Mux(self.i_addr[0], self.i_wdata[8:],
self.i_wdata[:8]))
# do we have space available for it?
with m.If(~r6_tx_full.value):
# yes, store it and set that we've used the space
m.d.sync += tx_data.eq(value)
m.d.comb += r6_tx_full.set.eq(1)
# and fold it into the CRC
m.d.comb += [crc.i_byte.eq(value), crc.i_start.eq(1)]
with m.Else():
# overflowed! drop the write and raise error.
m.d.comb += r1_tx_overflow.set.eq(1)
return m
rst = Signal()
ph1clk = ClockSignal("ph1")
ph1.rst = rst
test_daa = Signal()
m.submodules.alu2 = alu2 = ALU8()
carry_in = Signal()
sum9 = Signal(9)
sum8 = Signal(8)
sum5 = Signal(5)
m.d.ph1 += Assume(rst == 0)
m.d.comb += Assert(alu._ccs[6:] == 0b11)
with m.If((~test_daa) | ~Past(test_daa)):
with m.Switch(alu.func):
with m.Case(ALU8Func.ADD, ALU8Func.ADC):
# sumN = input1[:N] + input2[:N] (so sumN[N-1] is the carry bit)
with m.If(alu.func == ALU8Func.ADD):
m.d.comb += carry_in.eq(0)
with m.Else():
m.d.comb += carry_in.eq(alu.ccs[Flags.C])
h = sum5[4]
n = sum9[7]
c = sum9[8]
z = sum9[:8] == 0
v = sum8[7] ^ c
m.d.comb += [
sum9.eq(alu.input1 + alu.input2 + carry_in),
sum8.eq(alu.input1[:7] + alu.input2[:7] + carry_in),
def elaborate(self, platform: Platform) -> Module:
m = Module()
m.d.sync += self.PSW.eq(self._psw)
m.d.comb += self._psw.eq(self.PSW)
with m.Switch(self.oper):
with m.Case(Operation.NOP):
if self.verification is Operation.NOP:
with m.If(~Initial()):
m.d.comb += [
Assert(self._psw.N == self.PSW.N),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == self.PSW.Z),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.ADC):
low = Cat(self.result[:4], self._psw.H)
high = Cat(self.result[4:], self._psw.C)
m.d.comb += [
low.eq(self.inputa[:4] + self.inputb[:4] + self.PSW.C),
high.eq(self.inputa[4:] + self.inputb[4:] + self._psw.H),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
self._psw.V.eq(self.result[7] != self._psw.C),
]
if self.verification is Operation.ADC:
r = Signal(8)
f = Signal(9)
h = Signal(5)
m.d.comb += [
r.eq(self.inputa.as_signed() +
self.inputb.as_signed() + self.PSW.C),
f.eq(self.inputa + self.inputb + self.PSW.C),
h.eq(self.inputa[:4] + self.inputb[:4] + self.PSW.C),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self.result == f[:8]),
Assert(self._psw.N == f[7]),
Assert(self._psw.V == (f[7] ^ f[8])),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == h[4]),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(f[:8].bool())),
Assert(self._psw.C == f[8]),
]
with m.Case(Operation.SBC):
low = Cat(self.result[:4], self._psw.H)
high = Cat(self.result[4:], self._psw.C)
m.d.comb += [
low.eq(self.inputa[:4] - self.inputb[:4] - self.PSW.C),
high.eq(self.inputa[4:] - self.inputb[4:] - self._psw.H),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
self._psw.V.eq(self.result[7] != self._psw.C),
]
if self.verification is Operation.SBC:
r = Signal(8)
f = Signal(9)
h = Signal(5)
m.d.comb += [
r.eq(self.inputa.as_signed() -
self.inputb.as_signed() - self.PSW.C),
f.eq(self.inputa - self.inputb - self.PSW.C),
h.eq(self.inputa[:4] - self.inputb[:4] - self.PSW.C),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self.result == f[:8]),
Assert(self._psw.N == f[7]),
Assert(self._psw.V == (f[7] ^ f[8])),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == h[4]),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(f[:8].bool())),
Assert(self._psw.C == f[8]),
]
with m.Case(Operation.CMP):
full = Cat(self.result, self._psw.C)
m.d.comb += [
full.eq(self.inputa.as_signed() - self.inputb.as_signed()),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
self._psw.V.eq(self.result[7] != self._psw.C),
]
if self.verification is Operation.CMP:
r = Signal(9)
m.d.comb += r.eq(self.inputa.as_signed() -
self.inputb.as_signed())
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r[:8]),
Assert(self._psw.N == r[7]),
Assert(self._psw.V == (r[7] ^ r[8])),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r[:8].bool())),
Assert(self._psw.C == r[8]),
]
with m.Case(Operation.AND):
m.d.comb += [
self.result.eq(self.inputa & self.inputb),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.AND:
r = Signal(8)
m.d.comb += r.eq(self.inputa & self.inputb)
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == r[7]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.OOR):
m.d.comb += [
self.result.eq(self.inputa | self.inputb),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.OOR:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa | self.inputb),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == r[7]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.EOR):
m.d.comb += [
self.result.eq(self.inputa ^ self.inputb),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.EOR:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa ^ self.inputb),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == r[7]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.INC):
m.d.comb += [
self.result.eq(self.inputa + 1),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.INC:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa + 1),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == r[7]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.DEC):
m.d.comb += [
self.result.eq(self.inputa - 1),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.DEC:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa - 1),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == r[7]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.ASL):
m.d.comb += [
Cat(self.result,
self._psw.C).eq(Cat(Const(0), self.inputa)),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.ASL:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa * 2),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == self.inputa[6]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.inputa[7]),
]
with m.Case(Operation.LSR):
m.d.comb += [
Cat(self._psw.C,
self.result).eq(Cat(self.inputa, Const(0))),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.LSR:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa // 2),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == 0),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.inputa[0]),
]
with m.Case(Operation.ROL):
m.d.comb += [
Cat(self.result,
self._psw.C).eq(Cat(self.PSW.C, self.inputa)),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.ROL:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa * 2 + self.PSW.C),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == self.inputa[6]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.inputa[7]),
]
with m.Case(Operation.ROR):
m.d.comb += [
Cat(self._psw.C,
self.result).eq(Cat(self.inputa, self.PSW.C)),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.ROR:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa // 2 + Cat(Signal(7), self.PSW.C)),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == self.PSW.C),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r.bool())),
Assert(self._psw.C == self.inputa[0]),
]
with m.Case(Operation.XCN):
m.d.comb += [
self.result.eq(Cat(self.inputa[4:], self.inputa[:4])),
self._psw.N.eq(self.result.as_signed() < 0),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.XCN:
r = Signal(8)
m.d.comb += [
r.eq(self.inputa * 16 + self.inputa // 16),
]
with m.If(~Initial()):
m.d.comb += [
Assert(self.result == r),
Assert(self._psw.N == self.inputa[3]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(self.inputa.bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.Case(Operation.DAA):
temp = Signal().like(self.inputa)
with m.If(self.PSW.C | (self.inputa > 0x99)):
m.d.comb += self._psw.C.eq(1)
m.d.comb += temp.eq(self.inputa + 0x60)
with m.Else():
m.d.comb += temp.eq(self.inputa)
with m.If(self.PSW.H | (temp[:4] > 0x09)):
m.d.comb += self.result.eq(temp + 0x06)
m.d.comb += [
self._psw.N.eq(self.result & 0x80),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.DAA:
with m.If(~Initial()):
m.d.comb += [Assert(False)]
with m.Case(Operation.DAS):
temp = Signal().like(self.inputa)
with m.If(~self.PSW.C | (self.inputa > 0x99)):
m.d.comb += self._psw.C.eq(0)
m.d.comb += temp.eq(self.inputa - 0x60)
with m.Else():
m.d.comb += temp.eq(self.inputa)
with m.If(~self.PSW.H | (temp[:4] > 0x09)):
m.d.comb += self.result.eq(temp - 0x06)
m.d.comb += [
self._psw.N.eq(self.result & 0x80),
self._psw.Z.eq(self.result == 0),
]
if self.verification is Operation.DAS:
with m.If(~Initial()):
m.d.comb += [Assert(False)]
# could be optimized with shift to right
with m.Case(Operation.MUL):
with m.Switch(self.count):
for i in range(0, 8):
with m.Case(i):
prod = self.inputa * self.inputb[i]
if i == 0:
prod = Cat(prod[0:7], ~prod[7], Const(1))
elif i == 7:
prod = Cat(~prod[0:7], prod[7], Const(1))
else:
prod = Cat(prod[0:7], ~prod[7])
m.d.sync += self.partial.eq(self.partial +
(prod << i))
m.d.sync += self.count.eq(i + 1)
with m.Case(8):
m.d.sync += self.partial_hi.eq(self.partial_lo)
m.d.sync += self.count.eq(9)
m.d.comb += [
self.result.eq(self.partial_hi),
self._psw.N.eq(self.partial_hi.as_signed() < 0),
self._psw.Z.eq(self.partial_hi == 0),
]
with m.Case(9):
m.d.sync += self.partial.eq(0)
m.d.sync += self.count.eq(0)
m.d.comb += [
self.result.eq(self.partial_hi),
]
if self.verification is Operation.MUL:
r = Signal(16)
m.d.comb += [
r.eq(self.inputa.as_signed() *
self.inputb.as_signed()),
Cover(self.count == 9),
]
with m.If(self.count == 9):
m.d.comb += [
Assert(Past(self.result) == r[8:16]),
Assert(self.result == r[0:8]),
Assert(self._psw.N == r[15]),
Assert(self._psw.V == self.PSW.V),
Assert(self._psw.P == self.PSW.P),
Assert(self._psw.B == self.PSW.B),
Assert(self._psw.H == self.PSW.H),
Assert(self._psw.I == self.PSW.I),
Assert(self._psw.Z == ~(r[8:16].bool())),
Assert(self._psw.C == self.PSW.C),
]
with m.If(~Initial() & (self.count == 0)):
m.d.comb += [
Assert(self.partial == 0),
Assert((Past(self.count) == 0)
| (Past(self.count) == 9)),
]
with m.If(~Initial() & (self.count != 0)):
m.d.comb += [
Assert(self.count == Past(self.count) + 1),
Assume(self.inputa == Past(self.inputa)),
Assume(self.inputb == Past(self.inputb)),
]
with m.Case(Operation.DIV):
over = Signal(reset=0)
with m.Switch(self.count):
with m.Case(0):
m.d.sync += self.partial_hi.eq(self.inputa) # Y
m.d.sync += self.count.eq(1)
with m.Case(1):
m.d.sync += self.partial_lo.eq(self.inputa) # A
m.d.sync += self.count.eq(2)
m.d.comb += self._psw.H.eq(
Mux(self.partial_hi[0:4] >= self.inputb[0:4], 1,
0))
for i in range(2, 11):
with m.Case(i):
tmp1_w = Cat(self.partial << 1, over)
tmp1_x = Signal(17)
tmp1_y = Signal(17)
tmp1_z = Signal(17)
tmp2 = self.inputb << 9
m.d.comb += tmp1_x.eq(tmp1_w)
with m.If(tmp1_w & 0x20000):
m.d.comb += tmp1_x.eq((tmp1_w & 0x1FFFF) | 1)
m.d.comb += tmp1_y.eq(tmp1_x)
with m.If(tmp1_x >= tmp2):
m.d.comb += tmp1_y.eq(tmp1_x ^ 1)
m.d.comb += tmp1_z.eq(tmp1_y)
with m.If(tmp1_y & 1):
m.d.comb += tmp1_z.eq((tmp1_y - tmp2)
& 0x1FFFF)
m.d.sync += Cat(self.partial, over).eq(tmp1_z)
m.d.sync += self.count.eq(i + 1)
with m.Case(11):
m.d.sync += self.count.eq(12)
m.d.comb += [
self.result.eq(
(Cat(self.partial, over) >> 9)), # Y %
]
with m.Case(12):
m.d.sync += self.partial.eq(0)
m.d.sync += over.eq(0)
m.d.sync += self.count.eq(0)
m.d.comb += [
self.result.eq(self.partial_lo), # A /
self._psw.N.eq(self.partial_lo.as_signed() < 0),
self._psw.V.eq(over),
self._psw.Z.eq(self.partial_lo == 0),
]
if self.verification is Operation.DIV:
m.d.comb += [
Cover(self.count == 12),
]
with m.If(self.count == 12):
m.d.comb += [Assert(False)]
return m
def assert_inc16(self, signal, ago):
if ago == 0:
self.m.d.ph1 += Assert(signal == (Past(signal) + 1)[:16])
else:
self.m.d.ph1 += Assert(
Past(signal, ago) == (Past(signal, ago + 1) + 1)[:16])
def is_instruction(self, instruction, max_cycle):
return self.m.If((Past(self.core.cycle) == max_cycle)
& (Past(self.core.registers.instr) == instruction))
if __name__ == '__main__':
parser = main_parser()
args = parser.parse_args()
b2d = Bin2Dec(8)
m = Module()
m.submodules.b2d = b2d
m.d.comb += Cover(b2d.o_digit_rd == 1)
m.d.comb += Cover(b2d.o_conv_rd == 1)
# o_digit_rd is a 1-cycle strobe
with m.If((Past(b2d.o_digit_rd, 2) == 0) & (Past(b2d.o_digit_rd, 1) == 1)):
m.d.comb += Assert(b2d.o_digit_rd == 0)
# i_bin_stb resets all outputs
with m.If(Past(b2d.i_bin_stb) == 1):
m.d.comb += Assert(b2d.o_digit == 0)
m.d.comb += Assert(b2d.o_digit_rd == 0)
m.d.comb += Assert(b2d.o_conv_rd == 0)
# o_digit is stable if o_digit_rd is low
with m.If((Past(ResetSignal()) == 0) & (Past(b2d.i_bin_stb) == 0) & (b2d.o_digit_rd == 0)):
m.d.comb += Assert(Stable(b2d.o_digit))
# o_digit_rd rises with o_conv_rd and falls on the next cycle
with m.If(Rose(b2d.o_conv_rd, 2)):
m.d.comb += Assert(Rose(b2d.o_digit_rd, 2))
def make_term():
if expect:
return Past(signal, n)
else:
return ~Past(signal, n)
def elaborate(self, platform: str):
#--------
m = Module()
#add_clk_domain(m, self.bus().clk)
#add_clk_from_domain(m, self.bus.clk())
#--------
#--------
# Local variables
bus = self.bus()
loc = Blank()
loc.arr = Array([Signal(bus.shape_t()) for _ in range(bus.SIZE())])
loc.PTR_WIDTH = width_from_arg(bus.SIZE())
loc.rd = Signal(loc.PTR_WIDTH)
loc.wr = Signal(loc.PTR_WIDTH)
loc.RD_PLUS_1 = loc.rd + 0x1
loc.WR_PLUS_1 = loc.wr + 0x1
loc.incr_rd = Signal(loc.PTR_WIDTH)
loc.incr_wr = Signal(loc.PTR_WIDTH)
loc.next_empty = Signal()
loc.next_full = Signal()
loc.next_rd = Signal(loc.PTR_WIDTH)
loc.next_wr = Signal(loc.PTR_WIDTH)
loc.rst = ResetSignal("sync")
#loc.curr_en_cat = Signal(2)
if self.FORMAL():
loc.formal = Blank()
loc.formal.last_rd_val = Signal(bus.shape_t())
loc.formal.test_wr = Signal(loc.PTR_WIDTH)
#loc.formal.empty = Signal()
#loc.formal.full = Signal()
loc.formal.wd_cnt = Signal(bus.shape_t(), reset=0xa0)
#--------
#--------
if self.FORMAL():
m.d.sync \
+= [
loc.formal.last_rd_val.eq(loc.arr[loc.rd]),
loc.formal.wd_cnt.eq(loc.formal.wd_cnt - 0x10)
]
m.d.comb \
+= [
loc.formal.test_wr.eq((loc.wr + 0x1) % bus.SIZE()),
]
#--------
#--------
# Combinational logic
m.d.comb \
+= [
loc.incr_rd.eq(Mux(loc.RD_PLUS_1 < bus.SIZE(),
(loc.rd + 0x1), 0x0)),
loc.incr_wr.eq(Mux(loc.WR_PLUS_1 < bus.SIZE(),
(loc.wr + 0x1), 0x0)),
loc.next_empty.eq(loc.next_wr == loc.next_rd),
#loc.next_full.eq((loc.next_wr + 0x1) == loc.next_rd),
#loc.curr_en_cat.eq(Cat(bus.rd_en, bus.wr_en)),
]
with m.If(bus.rd_en & (~bus.empty)):
m.d.comb += loc.next_rd.eq(loc.incr_rd)
with m.Else():
m.d.comb += loc.next_rd.eq(loc.rd)
with m.If(bus.wr_en & (~bus.full)):
m.d.comb \
+= [
loc.next_wr.eq(loc.incr_wr),
loc.next_full.eq((loc.incr_wr + 0x1) == loc.next_rd),
]
with m.Else():
m.d.comb \
+= [
loc.next_wr.eq(loc.wr),
loc.next_full.eq(loc.incr_wr == loc.next_rd),
]
#--------
#--------
# Clocked behavioral code
with m.If(loc.rst):
#for elem in loc.arr:
# m.d.sync += elem.eq(bus.shape_t()())
m.d.sync \
+= [
loc.rd.eq(0x0),
loc.wr.eq(0x0),
#bus.rd_data.eq(bus.shape_t()()),
bus.empty.eq(0b1),
bus.full.eq(0b0),
]
with m.Else(): # If(~loc.rst):
#--------
m.d.sync \
+= [
bus.empty.eq(loc.next_empty),
bus.full.eq(loc.next_full),
loc.rd.eq(loc.next_rd),
loc.wr.eq(loc.next_wr),
]
with m.If(bus.rd_en & (~bus.empty)):
m.d.sync += bus.rd_data.eq(loc.arr[loc.rd])
with m.If(bus.wr_en & (~bus.full)):
m.d.sync += loc.arr[loc.wr].eq(bus.wr_data)
#--------
#--------
if self.FORMAL():
with m.If(Fell(loc.rst)):
m.d.sync \
+= [
Assert(loc.rd == 0x0),
Assert(loc.wr == 0x0),
Assert(bus.empty == 0b1),
Assert(bus.full == 0b0),
]
with m.Else(): # If(~Fell(loc.rst)):
m.d.sync \
+= [
Assert(bus.empty == Past(loc.next_empty)),
Assert(bus.full == Past(loc.next_full)),
Assert(loc.rd == Past(loc.next_rd)),
Assert(loc.wr == Past(loc.next_wr)),
]
with m.If(Past(bus.rd_en)):
with m.If(Past(bus.empty)):
m.d.sync \
+= [
#Assert(Stable(bus.empty)),
Assert(Stable(loc.rd)),
]
with m.Else(): # If(~Past(bus.empty)):
#with m.If(~Past(bus.wr_en)):
m.d.sync \
+= [
Assert(bus.rd_data
== loc.arr[Past(loc.rd)])
]
with m.If(Past(bus.wr_en)):
with m.If(Past(bus.full)):
m.d.sync \
+= [
Assert(Stable(loc.wr)),
]
#with m.Else(): # If(~Past(bus.full)):
# m.d.sync \
# += [
# Assert(Past(bus.wr_data))
# ]
with m.Switch(Cat(bus.empty, bus.full)):
with m.Case(0b00):
m.d.sync \
+= [
Assume(loc.wr != loc.rd),
Assume(loc.formal.test_wr != loc.rd),
]
with m.Case(0b01):
m.d.sync \
+= [
Assert(loc.wr == loc.rd)
]
with m.Case(0b10):
m.d.sync \
+= [
Assert(loc.formal.test_wr == loc.rd),
]
m.d.sync \
+= [
Assert(~(bus.empty & bus.full)),
#Assume(~Stable(bus.wr_data)),
#Assume(bus.wr_data == loc.formal.wd_cnt),
]
#--------
#--------
#--------
return m
def elaborate(self, platform):
m = Module()
m.submodules.cpu_core = cpu_core = self.cpu_core
m.submodules.bootrom_r = bootrom_r = self.bootrom.read_port(
transparent=False)
m.submodules.bootrom_w = bootrom_w = self.bootrom.write_port()
m.submodules.reset_req = reset_req = self.reset_req
m.submodules.uart = uart = self.uart
m.submodules.timer = timer = self.timer
m.submodules.snes = snes = self.snes
# hook up main bus. the main RAM gets the first half and the boot ROM
# gets the second (though nominally, it's from 0xFF00 to 0xFFFF)
mainram_en = Signal()
bootrom_en = Signal()
# the code area of the boot ROM can't be written to to avoid destroying
# it by accident. if it got destroyed, then the bootloader wouldn't work
# after reset; a full reconfiguration would be required.
bootrom_writable = Signal()
m.d.comb += [
mainram_en.eq(cpu_core.o_bus_addr[-1] == 0),
bootrom_en.eq(cpu_core.o_bus_addr[-1] == 1),
bootrom_writable.eq((cpu_core.o_bus_addr & 0xC0) == 0xC0)
]
# wire the main bus to the memories
m.d.comb += [
# address bus
bootrom_r.addr.eq(cpu_core.o_bus_addr),
bootrom_w.addr.eq(cpu_core.o_bus_addr),
self.memory_signals.o_addr.eq(cpu_core.o_bus_addr),
# write data
bootrom_w.data.eq(cpu_core.o_mem_data),
self.memory_signals.o_wdata.eq(cpu_core.o_mem_data),
# enables
bootrom_r.en.eq(bootrom_en & cpu_core.o_mem_re),
bootrom_w.en.eq(bootrom_en & cpu_core.o_mem_we & bootrom_writable),
self.memory_signals.o_re.eq(mainram_en & cpu_core.o_mem_re),
self.memory_signals.o_we.eq(mainram_en & cpu_core.o_mem_we),
]
# mux read results back to the cpu bus. the cpu gets the read value if
# it addressed the memory last cycle. it can only address one memory at
# a time (if it did more then all the results would be ORed together).
mainram_rdata = Signal(16)
bootrom_rdata = Signal(16)
m.d.comb += [
mainram_rdata.eq(
Mux(Past(mainram_en), self.memory_signals.i_rdata, 0)),
bootrom_rdata.eq(Mux(Past(bootrom_en), bootrom_r.data, 0)),
cpu_core.i_mem_data.eq(mainram_rdata | bootrom_rdata),
]
# the main RAM runs with the system clock
m.d.comb += [
self.memory_signals.o_clock.eq(ClockSignal("sync")),
self.memory_signals.o_reset.eq(ResetSignal("sync")),
]
# split up the external bus into (at most) 16 regions of 16 registers.
# we use the first 128 words and last 128 words of the bus since those
# regions can be addressed with the 1-word form of the external bus
# instructions. each peripheral gets 1 read and 1 write enable bit, 4
# address bits, 16 write data bits, and gives back 16 read data bits
NUM_PERIPHS = 4
periph_en = tuple(Signal(1) for _ in range(NUM_PERIPHS))
periph_re = tuple(Signal(1) for _ in range(NUM_PERIPHS))
periph_we = tuple(Signal(1) for _ in range(NUM_PERIPHS))
periph_addr = Signal(4)
periph_wdata = Signal(16)
periph_rdata = tuple(Signal(16) for _ in range(NUM_PERIPHS))
m.d.comb += periph_addr.eq(cpu_core.o_bus_addr[:4])
m.d.comb += periph_wdata.eq(cpu_core.o_ext_data)
# hook up enable bits
x_addr = cpu_core.o_bus_addr
for pi in range(NUM_PERIPHS):
m.d.comb += [
periph_en[pi].eq((x_addr[-1] == (pi >> 3))
& (x_addr[4:7] == (pi & 7))),
periph_re[pi].eq(cpu_core.o_ext_re & periph_en[pi]),
periph_we[pi].eq(cpu_core.o_ext_we & periph_en[pi]),
]
# mux peripheral read data back to the CPU
result_expr = Const(0, 16)
for pi in range(NUM_PERIPHS):
# this peripheral gets to put its result on the bus if it was
# addressed last cycle
result_expr = result_expr | \
Mux(Past(periph_en[pi]), periph_rdata[pi], 0)
m.d.comb += cpu_core.i_ext_data.eq(result_expr)
# hook up the reset request peripheral
m.d.comb += [
reset_req.i_re.eq(periph_re[p_map.reset_req.periph_num]),
reset_req.i_we.eq(periph_we[p_map.reset_req.periph_num]),
reset_req.i_addr.eq(periph_addr),
reset_req.i_wdata.eq(periph_wdata),
periph_rdata[p_map.reset_req.periph_num].eq(reset_req.o_rdata),
self.o_reset_req.eq(reset_req.o_reset_req),
]
# hook up the UART
m.d.comb += [
uart.i_re.eq(periph_re[p_map.uart.periph_num]),
uart.i_we.eq(periph_we[p_map.uart.periph_num]),
uart.i_addr.eq(periph_addr),
uart.i_wdata.eq(periph_wdata),
periph_rdata[p_map.uart.periph_num].eq(uart.o_rdata),
uart.i_rx.eq(self.uart_signals.i_rx),
self.uart_signals.o_tx.eq(uart.o_tx),
]
# hook up the timers
m.d.comb += [
timer.i_re.eq(periph_re[p_map.timer.periph_num]),
timer.i_we.eq(periph_we[p_map.timer.periph_num]),
timer.i_addr.eq(periph_addr),
timer.i_wdata.eq(periph_wdata),
periph_rdata[p_map.timer.periph_num].eq(timer.o_rdata),
]
# hook up the SNES interface
m.d.comb += [
snes.i_re.eq(periph_re[p_map.snes.periph_num]),
snes.i_we.eq(periph_we[p_map.snes.periph_num]),
snes.i_addr.eq(periph_addr),
snes.i_wdata.eq(periph_wdata),
periph_rdata[p_map.snes.periph_num].eq(snes.o_rdata),
]
return m
def validate(self): with self.is_running(): with self.is_instruction(0x1B, 2): self.assert_equals(self.registers.a, Past(self.registers.a) + Past(self.registers.b)) self.assert_end_of_instruction()
def build_formal(bld: Builder):
m = Module()
in_data = AnySeq(8)
en_data = AnySeq(1)
hsync = AnySeq(1)
vsync = AnySeq(1)
enc_char = Signal(10)
real_chr_bias = Signal(signed(5))
real_dc_bias = Signal(signed(5))
m.submodules.enc = enc = TMDSEncoder()
m.submodules.dec = dec = TMDSDecoder()
m.d.comb += [
enc.i_data.eq(in_data),
enc.i_en_data.eq(en_data),
enc.i_hsync.eq(hsync),
enc.i_vsync.eq(vsync),
dec.i_char.eq(enc.o_char),
enc_char.eq(enc.o_char),
]
m.d.comb += [
real_chr_bias.eq(popcount(enc.o_char) - 5),
Assert(real_dc_bias >= -5),
Assert(real_dc_bias <= +5),
Assert(real_dc_bias[:4] == enc.dc_bias),
]
m.d.sync += [
real_dc_bias.eq(real_dc_bias + real_chr_bias),
]
with m.If(~enc.i_en_data):
m.d.sync += real_dc_bias.eq(real_dc_bias)
m.d.comb += Cover(
(Past(dec.o_en_data, 4) & (Past(enc.o_char, 4)[8:10] == 0b00))
& (Past(dec.o_en_data, 3) & (Past(enc.o_char, 3)[8:10] == 0b01))
& (Past(dec.o_en_data, 2) & (Past(enc.o_char, 2)[8:10] == 0b10))
& (Past(dec.o_en_data, 1) & (Past(enc.o_char, 1)[8:10] == 0b11))
& (dec.o_vsync))
m.d.comb += Assert(dec.o_en_data == enc.i_en_data)
with m.If(dec.o_en_data):
m.d.comb += Assert(dec.o_data == enc.i_data)
# Check that XNOR choice matches reference algorithm
in_pop = Signal(4)
use_xnor = Signal()
m.d.comb += [
in_pop.eq(popcount(in_data)),
use_xnor.eq((in_pop > 4) | ((in_pop == 4) & (in_data[0] == 0))),
Assert(enc.o_char[8] == ~use_xnor),
]
with m.Else():
m.d.comb += [
Assert(dec.o_hsync == enc.i_hsync),
Assert(dec.o_vsync == enc.i_vsync),
]
with bld.temp_open("formal.il") as f:
il_text = rtlil.convert(m,
ports=[enc_char, real_chr_bias, real_dc_bias])
f.write(il_text)
def capture(self, m: Core, core: Core, past: int):
comb = m.d.comb
if past > 0:
prefix = f"past{past}"
else:
prefix = "now"
self.r = RegisterFile(core.xlen, prefix=prefix)
for i in range(self.r.main_gpr_count()):
comb += self.r[i].eq(Past(core.register_file.r[i], past))
comb += self.r.pc.eq(Past(core.pc, past))
# TODO: move to additional structure
self.itype = IType(prefix=f"{prefix}_i")
self.itype.elaborate(comb, Past(core.current_instruction, past))
self.jtype = JType(prefix=f"{prefix}_j")
self.jtype.elaborate(comb, Past(core.current_instruction, past))
self.utype = UType(prefix=f"{prefix}_u")
self.utype.elaborate(comb, Past(core.current_instruction, past))
self.btype = BType(prefix=f"{prefix}_b")
self.btype.elaborate(comb, Past(core.current_instruction, past))
# TODO: membus
self.input_ready = Signal.like(core.mem2core.ready,
name=f"{prefix}_input_ready")
self.input_data = Array([
Signal(core.xlen, name=f"{prefix}_input_{i}")
for i in range(core.look_ahead)
])
self.cycle = Signal.like(core.cycle, name=f"{prefix}_cycle")
comb += self.cycle.eq(Past(core.cycle, past))
# TODO: move to structure
self.mem2core_addr = Signal.like(core.mem2core.addr,
name=f"{prefix}_mem2core_addr")
self.mem2core_en = Signal.like(core.mem2core.en,
name=f"{prefix}_mem2core_en")
self.mem2core_seq = Signal.like(core.mem2core.seq,
name=f"{prefix}_mem2core_seq")
comb += self.mem2core_addr.eq(Past(core.mem2core.addr, past))
comb += self.mem2core_en.eq(Past(core.mem2core.en, past))
comb += self.mem2core_seq.eq(Past(core.mem2core.seq, past))
comb += self.input_ready.eq(Past(core.mem2core.ready, past))
comb += self.input_data[0].eq(Past(core.mem2core.value, past))
if verification is not None:
# Cycle counter
cycle2 = Signal(6, reset_less=True)
m.d.ph1 += cycle2.eq(cycle2 + 1)
# Force a reset
# m.d.comb += Assume(rst == (cycle2 < 8))
with m.If(cycle2 == 20):
m.d.ph1 += Cover(core.formalData.snapshot_taken
& core.end_instr_flag)
m.d.ph1 += Assume(core.formalData.snapshot_taken
& core.end_instr_flag)
# Verify reset does what it's supposed to
with m.If(Past(rst, 4) & ~Past(rst, 3) & ~Past(rst, 2) & ~Past(rst)):
m.d.ph1 += Assert(Past(core.Addr, 2) == 0xFFFE)
m.d.ph1 += Assert(Past(core.Addr) == 0xFFFF)
m.d.ph1 += Assert(core.Addr[8:] == Past(core.Din, 2))
m.d.ph1 += Assert(core.Addr[:8] == Past(core.Din))
m.d.ph1 += Assert(core.Addr == core.pc)
main_runner(parser, args, m, ports=core.ports() + [ph1clk, rst])
else:
# Fake memory
mem = {
0xFFFE: 0x12,
0xFFFF: 0x34,
0x1234: 0x7E, # JMP 0xA010
0x1235: 0xA0,
def formal(cls) -> Tuple[Module, List[Signal]]:
"""Formal verification for the register card."""
m = Module()
ph1 = ClockDomain("ph1")
ph2 = ClockDomain("ph2")
regs = RegCard()
m.domains += [ph1, ph2]
m.submodules += regs
# Generate the ph1 and ph2 clocks.
cycle_count = Signal(8, reset=0, reset_less=True)
phase_count = Signal(3, reset=0, reset_less=True)
m.d.sync += phase_count.eq(phase_count + 1)
with m.Switch(phase_count):
with m.Case(0, 1, 2):
m.d.comb += ph1.clk.eq(1)
with m.Default():
m.d.comb += ph1.clk.eq(0)
with m.Switch(phase_count):
with m.Case(1, 4):
m.d.comb += ph2.clk.eq(0)
with m.Default():
m.d.comb += ph2.clk.eq(1)
with m.If(phase_count == 5):
m.d.sync += phase_count.eq(0)
m.d.sync += cycle_count.eq(cycle_count + 1)
# This is how we expect to use the card.
with m.If(phase_count > 0):
m.d.comb += [
Assume(Stable(regs.reg_x)),
Assume(Stable(regs.reg_y)),
Assume(Stable(regs.reg_z)),
Assume(Stable(regs.reg_page)),
Assume(Stable(regs.reg_to_x)),
Assume(Stable(regs.reg_to_y)),
Assume(Stable(regs.data_z)),
]
# Figure out how to get to the point where X and Y are nonzero and different.
m.d.comb += Cover((regs.data_x != 0) & (regs.data_y != 0)
& (regs.data_x != regs.data_y))
# X and Y buses should not change during a cycle, except for the first phase
with m.Switch(phase_count):
with m.Case(2, 3, 4, 5):
with m.If(regs.data_x != 0):
m.d.comb += Assert(Stable(regs.data_x))
with m.If(regs.data_y != 0):
m.d.comb += Assert(Stable(regs.data_y))
# X and Y buses should be zero if there is no data transfer.
with m.If(regs.reg_to_x == 0):
m.d.comb += Assert(regs.data_x == 0)
with m.If(regs.reg_to_y == 0):
m.d.comb += Assert(regs.data_y == 0)
with m.If(phase_count > 0):
# X and Y buses should be zero if we read from register 0.
with m.If(regs.reg_to_x & (regs.reg_x == 0)):
m.d.comb += Assert(regs.data_x == 0)
with m.If(regs.reg_to_y & (regs.reg_y == 0)):
m.d.comb += Assert(regs.data_y == 0)
write_pulse = Signal()
m.d.comb += write_pulse.eq(phase_count != 4)
# On write, the data should have been written to both banks.
past_mem_addr = Signal(6)
m.d.comb += past_mem_addr[:5].eq(Past(regs.reg_z))
m.d.comb += past_mem_addr[5].eq(Past(regs.reg_page))
past_z = Past(regs.data_z)
with m.If(Rose(write_pulse)):
m.d.comb += Assert(regs._x_bank._mem[past_mem_addr] == past_z)
m.d.comb += Assert(regs._y_bank._mem[past_mem_addr] == past_z)
# Pick an register, any register, except 0. We assert that unless
# it is written, its data will not change.
check_addr = AnyConst(5)
check_page = AnyConst(1)
saved_data = Signal(32)
stored_x_data = Signal(32)
stored_y_data = Signal(32)
write_pulse_domain = ClockDomain("write_pulse_domain", local=True)
m.domains.write_pulse_domain = write_pulse_domain
write_pulse_domain.clk = write_pulse
mem_addr = Signal(6)
m.d.comb += Assume(check_addr != 0)
m.d.comb += [
mem_addr[:5].eq(check_addr),
mem_addr[5].eq(check_page),
stored_x_data.eq(regs._x_bank._mem[mem_addr]),
stored_y_data.eq(regs._y_bank._mem[mem_addr]),
]
with m.If((regs.reg_z == check_addr) & (regs.reg_page == check_page)):
m.d.write_pulse_domain += saved_data.eq(regs.data_z)
with m.If(Initial()):
m.d.comb += Assume(saved_data == stored_x_data)
m.d.comb += Assume(stored_x_data == stored_y_data)
with m.Else():
m.d.comb += Assert(saved_data == stored_x_data)
m.d.comb += Assert(saved_data == stored_y_data)
return m, [regs.data_z, regs.reg_to_x, regs.reg_to_y,
regs.reg_x, regs.reg_y, regs.reg_z, regs.reg_page, ph1.clk, ph2.clk, saved_data,
stored_x_data, stored_y_data]