xref: /XiangShan/src/main/scala/device/AXI4RAM.scala (revision dc597826530cb6803c2396d6ab0e5eb176b732e0)
1/***************************************************************************************
2* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
3* Copyright (c) 2020-2021 Peng Cheng Laboratory
4*
5* XiangShan is licensed under Mulan PSL v2.
6* You can use this software according to the terms and conditions of the Mulan PSL v2.
7* You may obtain a copy of Mulan PSL v2 at:
8*          http://license.coscl.org.cn/MulanPSL2
9*
10* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
11* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
12* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
13*
14* See the Mulan PSL v2 for more details.
15***************************************************************************************/
16
17package device
18
19import chipsalliance.rocketchip.config.Parameters
20import chisel3._
21import chisel3.util._
22import Chisel.BlackBox
23import freechips.rocketchip.amba.axi4.{AXI4SlaveNode, AXI4EdgeParameters, AXI4MasterNode}
24import freechips.rocketchip.diplomacy.{AddressSet, InModuleBody, LazyModule, LazyModuleImp, RegionType}
25import top.HaveAXI4MemPort
26import xiangshan.HasXSParameter
27import utils.MaskExpand
28
29class RAMHelper(memByte: BigInt) extends BlackBox {
30  val DataBits = 64
31  val io = IO(new Bundle {
32    val clk   = Input(Clock())
33    val en    = Input(Bool())
34    val rIdx  = Input(UInt(DataBits.W))
35    val rdata = Output(UInt(DataBits.W))
36    val wIdx  = Input(UInt(DataBits.W))
37    val wdata = Input(UInt(DataBits.W))
38    val wmask = Input(UInt(DataBits.W))
39    val wen   = Input(Bool())
40  })
41}
42
43class AXI4RAM
44(
45  address: Seq[AddressSet],
46  memByte: Long,
47  useBlackBox: Boolean = false,
48  executable: Boolean = true,
49  beatBytes: Int = 8,
50  burstLen: Int = 16,
51)(implicit p: Parameters)
52  extends AXI4SlaveModule(address, executable, beatBytes, burstLen)
53{
54  override lazy val module = new AXI4SlaveModuleImp(this){
55
56    val split = beatBytes / 8
57    val bankByte = memByte / split
58    val offsetBits = log2Up(memByte)
59
60    require(address.length >= 1)
61    val baseAddress = address(0).base
62
63    def index(addr: UInt) = ((addr - baseAddress.U)(offsetBits - 1, 0) >> log2Ceil(beatBytes)).asUInt()
64
65    def inRange(idx: UInt) = idx < (memByte / beatBytes).U
66
67    val wIdx = index(waddr) + writeBeatCnt
68    val rIdx = index(raddr) + readBeatCnt
69    val wen = in.w.fire() && inRange(wIdx)
70    require(beatBytes >= 8)
71
72    val rdata = if (useBlackBox) {
73      val mems = (0 until split).map {_ => Module(new RAMHelper(bankByte))}
74      mems.zipWithIndex map { case (mem, i) =>
75        mem.io.clk   := clock
76        mem.io.en    := !reset.asBool() && ((state === s_rdata) || (state === s_wdata))
77        mem.io.rIdx  := (rIdx << log2Up(split)) + i.U
78        mem.io.wIdx  := (wIdx << log2Up(split)) + i.U
79        mem.io.wdata := in.w.bits.data((i + 1) * 64 - 1, i * 64)
80        mem.io.wmask := MaskExpand(in.w.bits.strb((i + 1) * 8 - 1, i * 8))
81        mem.io.wen   := wen
82      }
83      val rdata = mems.map {mem => mem.io.rdata}
84      Cat(rdata.reverse)
85    } else {
86      val mem = Mem(memByte / beatBytes, Vec(beatBytes, UInt(8.W)))
87
88      val wdata = VecInit.tabulate(beatBytes) { i => in.w.bits.data(8 * (i + 1) - 1, 8 * i) }
89      when(wen) {
90        mem.write(wIdx, wdata, in.w.bits.strb.asBools())
91      }
92
93      Cat(mem.read(rIdx).reverse)
94    }
95    in.r.bits.data := rdata
96  }
97}
98
99class AXI4RAMWrapper
100(snode: AXI4SlaveNode, memByte: Long, useBlackBox: Boolean = false)
101(implicit p: Parameters)
102  extends LazyModule {
103
104  val mnode = AXI4MasterNode(List(snode.in.head._2.master))
105
106  val portParam = snode.portParams.head
107  val slaveParam = portParam.slaves.head
108  val burstLen = portParam.maxTransfer / portParam.beatBytes
109  val ram = LazyModule(new AXI4RAM(
110    slaveParam.address, memByte, useBlackBox,
111    slaveParam.executable, portParam.beatBytes, burstLen
112  ))
113  ram.node := mnode
114
115  val io_axi4 = InModuleBody{ mnode.makeIOs() }
116  def connectToSoC(soc: HaveAXI4MemPort) = {
117    io_axi4 <> soc.memory
118  }
119
120  lazy val module = new LazyModuleImp(this){}
121}
122