Beispiel #1
0
 def elaborate(self, platform):
     bitstream = Signal(32)
     mcnt = Signal(9)
     mclk = Signal()
     sck = Signal()
     sd = Signal()
     lrck = Signal()
     m = Module()
     m.d.sync += [
         mcnt.eq(mcnt + 1),
     ]
     with m.If((mcnt == 0x00F) & (self.stb == True)):
         m.d.sync += [
             # I2S bitstream is MSB first, so reverse bits here.
             bitstream.eq(Cat(self.samples[0][::-1],
                              self.samples[1][::-1])),
             self.ack.eq(True),
         ]
     with m.Elif(mcnt == 0x00F):
         m.d.sync += [
             bitstream.eq(0),
             self.ack.eq(False),
         ]
     with m.Else():
         m.d.sync += [
             self.ack.eq(False),
         ]
     m.d.sync += [
         mclk.eq(mcnt[0]),
         sck.eq(mcnt[3]),
         sd.eq(bitstream.bit_select(mcnt[4:4 + 5] - 1, 1)),
         lrck.eq(mcnt[4 + 4]),
     ]
     m.d.comb += [
         self.i2s.mclk.eq(mclk),
         self.i2s.sck.eq(sck),
         self.i2s.sd.eq(sd),
         self.i2s.lrck.eq(lrck),
     ]
     return m
Beispiel #2
0
    def elaborate(self, platform: Platform) -> Module:
        m = Module()

        snoop_addr = Record(self.pc_layout)
        snoop_valid = Signal()

        # -------------------------------------------------------------------------
        # Performance counter
        # TODO: connect to CSR's performance counter
        with m.If(~self.s1_stall & self.s1_valid & self.s1_access):
            m.d.sync += self.access_cnt.eq(self.access_cnt + 1)
        with m.If(self.s2_valid & self.s2_miss & ~self.bus_valid
                  & self.s2_access):
            m.d.sync += self.miss_cnt.eq(self.miss_cnt + 1)
        # -------------------------------------------------------------------------

        way_layout = [('data', 32 * self.nwords),
                      ('tag', self.s1_address.tag.shape()), ('valid', 1),
                      ('sel_lru', 1), ('snoop_hit', 1)]
        if self.enable_write:
            way_layout.append(('sel_we', 1))

        ways = Array(
            Record(way_layout, name='way_idx{}'.format(_way))
            for _way in range(self.nways))
        fill_cnt = Signal.like(self.s1_address.offset)

        # Check hit/miss
        way_hit = m.submodules.way_hit = Encoder(self.nways)
        for idx, way in enumerate(ways):
            m.d.comb += way_hit.i[idx].eq((way.tag == self.s2_address.tag)
                                          & way.valid)

        m.d.comb += self.s2_miss.eq(way_hit.n)
        if self.enable_write:
            # Asumiendo que hay un HIT, indicar que la vía que dió hit es en la cual se va a escribir
            m.d.comb += ways[way_hit.o].sel_we.eq(self.s2_we & self.s2_valid)

        # set the LRU
        if self.nways == 1:
            # One way: LRU is useless
            lru = Const(0)  # self.nlines
        else:
            # LRU es un vector de N bits, cada uno indicado el set a reemplazar
            # como NWAY es máximo 2, cada LRU es de un bit
            lru = Signal(self.nlines)
            _lru = lru.bit_select(self.s2_address.line, 1)
            write_ended = self.bus_valid & self.bus_ack & self.bus_last  # err ^ ack = = 1
            access_hit = ~self.s2_miss & self.s2_valid & (way_hit.o == _lru)
            with m.If(write_ended | access_hit):
                m.d.sync += _lru.eq(~_lru)

        # read data from the cache
        m.d.comb += self.s2_rdata.eq(ways[way_hit.o].data.word_select(
            self.s2_address.offset, 32))

        # Internal Snoop
        snoop_use_cache = Signal()
        snoop_tag_match = Signal()
        snoop_line_match = Signal()
        snoop_cancel_refill = Signal()
        if not self.enable_write:
            bits_range = log2_int(self.end_addr - self.start_addr,
                                  need_pow2=False)

            m.d.comb += [
                snoop_addr.eq(self.dcache_snoop.addr),  # aux
                snoop_valid.eq(self.dcache_snoop.we & self.dcache_snoop.valid
                               & self.dcache_snoop.ack),
                snoop_use_cache.eq(snoop_addr[bits_range:] == (
                    self.start_addr >> bits_range)),
                snoop_tag_match.eq(snoop_addr.tag == self.s2_address.tag),
                snoop_line_match.eq(snoop_addr.line == self.s2_address.line),
                snoop_cancel_refill.eq(snoop_use_cache & snoop_valid
                                       & snoop_line_match & snoop_tag_match),
            ]
        else:
            m.d.comb += snoop_cancel_refill.eq(0)

        with m.FSM():
            with m.State('READ'):
                with m.If(self.s2_re & self.s2_miss & self.s2_valid):
                    m.d.sync += [
                        self.bus_addr.eq(self.s2_address),
                        self.bus_valid.eq(1),
                        fill_cnt.eq(self.s2_address.offset - 1)
                    ]
                    m.next = 'REFILL'
            with m.State('REFILL'):
                m.d.comb += self.bus_last.eq(fill_cnt == self.bus_addr.offset)
                with m.If(self.bus_ack):
                    m.d.sync += self.bus_addr.offset.eq(self.bus_addr.offset +
                                                        1)
                with m.If(self.bus_ack & self.bus_last | self.bus_err):
                    m.d.sync += self.bus_valid.eq(0)
                with m.If(~self.bus_valid | self.s1_flush
                          | snoop_cancel_refill):
                    m.next = 'READ'
                    m.d.sync += self.bus_valid.eq(0)

        # mark the way to use (replace)
        m.d.comb += ways[lru.bit_select(self.s2_address.line,
                                        1)].sel_lru.eq(self.bus_valid)

        # generate for N ways
        for way in ways:
            # create the memory structures for valid, tag and data.
            valid = Signal(self.nlines)  # Valid bits

            tag_m = Memory(width=len(way.tag), depth=self.nlines)  # tag memory
            tag_rp = tag_m.read_port()
            snoop_rp = tag_m.read_port()
            tag_wp = tag_m.write_port()
            m.submodules += tag_rp, tag_wp, snoop_rp

            data_m = Memory(width=len(way.data),
                            depth=self.nlines)  # data memory
            data_rp = data_m.read_port()
            data_wp = data_m.write_port(
                granularity=32
            )  # implica que solo puedo escribir palabras de 32 bits.
            m.submodules += data_rp, data_wp

            # handle valid
            with m.If(self.s1_flush & self.s1_valid):  # flush
                m.d.sync += valid.eq(0)
            with m.Elif(way.sel_lru & self.bus_last
                        & self.bus_ack):  # refill ok
                m.d.sync += valid.bit_select(self.bus_addr.line, 1).eq(1)
            with m.Elif(way.sel_lru & self.bus_err):  # refill error
                m.d.sync += valid.bit_select(self.bus_addr.line, 1).eq(0)
            with m.Elif(self.s2_evict & self.s2_valid
                        & (way.tag == self.s2_address.tag)):  # evict
                m.d.sync += valid.bit_select(self.s2_address.line, 1).eq(0)

            # assignments
            m.d.comb += [
                tag_rp.addr.eq(
                    Mux(self.s1_stall, self.s2_address.line,
                        self.s1_address.line)),
                tag_wp.addr.eq(self.bus_addr.line),
                tag_wp.data.eq(self.bus_addr.tag),
                tag_wp.en.eq(way.sel_lru & self.bus_ack & self.bus_last),
                data_rp.addr.eq(
                    Mux(self.s1_stall, self.s2_address.line,
                        self.s1_address.line)),
                way.data.eq(data_rp.data),
                way.tag.eq(tag_rp.data),
                way.valid.eq(valid.bit_select(self.s2_address.line, 1))
            ]

            # update cache: CPU or Refill
            # El puerto de escritura se multiplexa debido a que la memoria solo puede tener un
            # puerto de escritura.
            if self.enable_write:
                update_addr = Signal(len(data_wp.addr))
                update_data = Signal(len(data_wp.data))
                update_we = Signal(len(data_wp.en))
                aux_wdata = Signal(32)

                with m.If(self.bus_valid):
                    m.d.comb += [
                        update_addr.eq(self.bus_addr.line),
                        update_data.eq(Repl(self.bus_data, self.nwords)),
                        update_we.bit_select(self.bus_addr.offset,
                                             1).eq(way.sel_lru & self.bus_ack),
                    ]
                with m.Else():
                    m.d.comb += [
                        update_addr.eq(self.s2_address.line),
                        update_data.eq(Repl(aux_wdata, self.nwords)),
                        update_we.bit_select(self.s2_address.offset,
                                             1).eq(way.sel_we & ~self.s2_miss)
                    ]
                m.d.comb += [
                    # Aux data: no tengo granularidad de byte en el puerto de escritura. Así que para el
                    # caso en el cual el CPU tiene que escribir, hay que construir el dato (wrord) a reemplazar
                    aux_wdata.eq(
                        Cat(
                            Mux(self.s2_sel[0],
                                self.s2_wdata.word_select(0, 8),
                                self.s2_rdata.word_select(0, 8)),
                            Mux(self.s2_sel[1],
                                self.s2_wdata.word_select(1, 8),
                                self.s2_rdata.word_select(1, 8)),
                            Mux(self.s2_sel[2],
                                self.s2_wdata.word_select(2, 8),
                                self.s2_rdata.word_select(2, 8)),
                            Mux(self.s2_sel[3],
                                self.s2_wdata.word_select(3, 8),
                                self.s2_rdata.word_select(3, 8)))),
                    #
                    data_wp.addr.eq(update_addr),
                    data_wp.data.eq(update_data),
                    data_wp.en.eq(update_we),
                ]
            else:
                m.d.comb += [
                    data_wp.addr.eq(self.bus_addr.line),
                    data_wp.data.eq(Repl(self.bus_data, self.nwords)),
                    data_wp.en.bit_select(self.bus_addr.offset,
                                          1).eq(way.sel_lru & self.bus_ack),
                ]

                # --------------------------------------------------------------
                # intenal snoop
                # for FENCE.i instruction
                _match_snoop = Signal()

                m.d.comb += [
                    snoop_rp.addr.eq(snoop_addr.line),  # read tag memory
                    _match_snoop.eq(snoop_rp.data == snoop_addr.tag),
                    way.snoop_hit.eq(snoop_use_cache & snoop_valid
                                     & _match_snoop
                                     & valid.bit_select(snoop_addr.line, 1)),
                ]
                # check is the snoop match a write from this core
                with m.If(way.snoop_hit):
                    m.d.sync += valid.bit_select(snoop_addr.line, 1).eq(0)
                # --------------------------------------------------------------

        return m
Beispiel #3
0
    def elaborate(self, platform):
        m = Module()

        way_layout = [
            ('data',     32 * self.nwords),
            ('tag',      self.s1_address.tag.shape()),
            ('valid',    1),
            ('sel_lru',  1)
        ]
        if self.enable_write:
            way_layout.append(('sel_we',   1))

        ways     = Array(Record(way_layout) for _way in range(self.nways))
        fill_cnt = Signal.like(self.s1_address.offset)
        # set the LRU
        if self.nways == 1:
            lru = Const(0)  # self.nlines
        else:
            lru = Signal(self.nlines)
            with m.If(self.bus_valid & self.bus_ack & self.bus_last):  # err ^ ack == 1
                _lru = lru.bit_select(self.s2_address.line, 1)
                m.d.sync += lru.bit_select(self.s2_address.line, 1).eq(~_lru)

        # hit/miss
        way_hit = m.submodules.way_hit = Encoder(self.nways)
        for idx, way in enumerate(ways):
            m.d.comb += way_hit.i[idx].eq((way.tag == self.s2_address.tag) & way.valid)

        m.d.comb += self.s2_miss.eq(way_hit.n)
        if self.enable_write:
            m.d.comb += ways[way_hit.o].sel_we.eq(self.s2_we & self.s2_valid)

        # read data
        m.d.comb += self.s2_rdata.eq(ways[way_hit.o].data.word_select(self.s2_address.offset, 32))

        with m.FSM():
            with m.State('READ'):
                with m.If(self.s2_re & self.s2_miss & self.s2_valid):
                    m.d.sync += [
                        self.bus_addr.eq(self.s2_address),  # WARNING extra_bits
                        self.bus_valid.eq(1),
                        fill_cnt.eq(self.s2_address.offset - 1)
                    ]
                    m.next = 'REFILL'
            with m.State('REFILL'):
                m.d.comb += self.bus_last.eq(fill_cnt == self.bus_addr.offset)
                with m.If(self.bus_ack):
                    m.d.sync += self.bus_addr.offset.eq(self.bus_addr.offset + 1)
                with m.If(self.bus_ack & self.bus_last | self.bus_err):
                    m.d.sync += self.bus_valid.eq(0)
                with m.If(~self.bus_valid | self.s1_flush):
                    # in case of flush, abort ongoing refill.
                    m.next = 'READ'
                    m.d.sync += self.bus_valid.eq(0)

        # mark the way to use (replace)
        m.d.comb += ways[lru.bit_select(self.s2_address.line, 1)].sel_lru.eq(self.bus_valid)

        # generate for N ways
        for way in ways:
            # create the memory structures for valid, tag and data.
            valid = Signal(self.nlines)

            tag_m  = Memory(width=len(way.tag), depth=self.nlines)
            tag_rp = tag_m.read_port()
            tag_wp = tag_m.write_port()
            m.submodules += tag_rp, tag_wp

            data_m  = Memory(width=len(way.data), depth=self.nlines)
            data_rp = data_m.read_port()
            data_wp = data_m.write_port(granularity=32)
            m.submodules += data_rp, data_wp

            # handle valid
            with m.If(self.s1_flush & self.s1_valid):  # flush
                m.d.sync += valid.eq(0)
            with m.Elif(way.sel_lru & self.bus_last & self.bus_ack):  # refill ok
                m.d.sync += valid.bit_select(self.bus_addr.line, 1).eq(1)
            with m.Elif(way.sel_lru & self.bus_err):  # refill error
                m.d.sync += valid.bit_select(self.bus_addr.line, 1).eq(0)
            with m.Elif(self.s2_evict & self.s2_valid & (way.tag == self.s2_address.tag)):  # evict
                m.d.sync += valid.bit_select(self.s2_address.line, 1).eq(0)

            # assignments
            m.d.comb += [
                tag_rp.addr.eq(Mux(self.s1_stall, self.s2_address.line, self.s1_address.line)),
                tag_wp.addr.eq(self.bus_addr.line),
                tag_wp.data.eq(self.bus_addr.tag),
                tag_wp.en.eq(way.sel_lru & self.bus_ack & self.bus_last),

                data_rp.addr.eq(Mux(self.s1_stall, self.s2_address.line, self.s1_address.line)),

                way.data.eq(data_rp.data),
                way.tag.eq(tag_rp.data),
                way.valid.eq(valid.bit_select(self.s2_address.line, 1))
            ]

            # update cache: CPU or Refill
            if self.enable_write:
                update_addr = Signal(len(data_wp.addr))
                update_data = Signal(len(data_wp.data))
                update_we   = Signal(len(data_wp.en))
                aux_wdata   = Signal(32)

                with m.If(self.bus_valid):
                    m.d.comb += [
                        update_addr.eq(self.bus_addr.line),
                        update_data.eq(Repl(self.bus_data, self.nwords)),
                        update_we.bit_select(self.bus_addr.offset, 1).eq(way.sel_lru & self.bus_ack),
                    ]
                with m.Else():
                    m.d.comb += [
                        update_addr.eq(self.s2_address.line),
                        update_data.eq(Repl(aux_wdata, self.nwords)),
                        update_we.bit_select(self.s2_address.offset, 1).eq(way.sel_we & ~self.s2_miss)
                    ]
                m.d.comb += [
                    aux_wdata.eq(Cat(
                        Mux(self.s2_sel[0], self.s2_wdata.word_select(0, 8), self.s2_rdata.word_select(0, 8)),
                        Mux(self.s2_sel[1], self.s2_wdata.word_select(1, 8), self.s2_rdata.word_select(1, 8)),
                        Mux(self.s2_sel[2], self.s2_wdata.word_select(2, 8), self.s2_rdata.word_select(2, 8)),
                        Mux(self.s2_sel[3], self.s2_wdata.word_select(3, 8), self.s2_rdata.word_select(3, 8))
                    )),
                    #
                    data_wp.addr.eq(update_addr),
                    data_wp.data.eq(update_data),
                    data_wp.en.eq(update_we),
                ]
            else:
                m.d.comb += [
                    data_wp.addr.eq(self.bus_addr.line),
                    data_wp.data.eq(Repl(self.bus_data, self.nwords)),
                    data_wp.en.bit_select(self.bus_addr.offset, 1).eq(way.sel_lru & self.bus_ack),
                ]

        return m