xref: /XiangShan/src/main/scala/device/AXI4RAM.scala (revision 73be64b3fc882a759f70d0852ba42d09c2a44af6)
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 chisel3.experimental.ExtModule
23import freechips.rocketchip.amba.axi4.{AXI4EdgeParameters, AXI4MasterNode, AXI4SlaveNode}
24import freechips.rocketchip.diplomacy.{AddressSet, InModuleBody, LazyModule, LazyModuleImp, RegionType}
25import utils.MaskExpand
26
27class RAMHelper(memByte: BigInt) extends ExtModule {
28  val DataBits = 64
29
30  val clk   = IO(Input(Clock()))
31  val en    = IO(Input(Bool()))
32  val rIdx  = IO(Input(UInt(DataBits.W)))
33  val rdata = IO(Output(UInt(DataBits.W)))
34  val wIdx  = IO(Input(UInt(DataBits.W)))
35  val wdata = IO(Input(UInt(DataBits.W)))
36  val wmask = IO(Input(UInt(DataBits.W)))
37  val wen   = IO(Input(Bool()))
38}
39
40class AXI4RAM
41(
42  address: Seq[AddressSet],
43  memByte: Long,
44  useBlackBox: Boolean = false,
45  executable: Boolean = true,
46  beatBytes: Int = 8,
47  burstLen: Int = 16,
48)(implicit p: Parameters)
49  extends AXI4SlaveModule(address, executable, beatBytes, burstLen)
50{
51  override lazy val module = new AXI4SlaveModuleImp(this){
52
53    val split = beatBytes / 8
54    val bankByte = memByte / split
55    val offsetBits = log2Up(memByte)
56
57    require(address.length >= 1)
58    val baseAddress = address(0).base
59
60    def index(addr: UInt) = ((addr - baseAddress.U)(offsetBits - 1, 0) >> log2Ceil(beatBytes)).asUInt()
61
62    def inRange(idx: UInt) = idx < (memByte / beatBytes).U
63
64    val wIdx = index(waddr) + writeBeatCnt
65    val rIdx = index(raddr) + readBeatCnt
66    val wen = in.w.fire() && inRange(wIdx)
67    require(beatBytes >= 8)
68
69    val rdata = if (useBlackBox) {
70      val mems = (0 until split).map {_ => Module(new RAMHelper(bankByte))}
71      mems.zipWithIndex map { case (mem, i) =>
72        mem.clk   := clock
73        mem.en    := !reset.asBool() && ((state === s_rdata) || (state === s_wdata))
74        mem.rIdx  := (rIdx << log2Up(split)) + i.U
75        mem.wIdx  := (wIdx << log2Up(split)) + i.U
76        mem.wdata := in.w.bits.data((i + 1) * 64 - 1, i * 64)
77        mem.wmask := MaskExpand(in.w.bits.strb((i + 1) * 8 - 1, i * 8))
78        mem.wen   := wen
79      }
80      val rdata = mems.map {mem => mem.rdata}
81      Cat(rdata.reverse)
82    } else {
83      val mem = Mem(memByte / beatBytes, Vec(beatBytes, UInt(8.W)))
84
85      val wdata = VecInit.tabulate(beatBytes) { i => in.w.bits.data(8 * (i + 1) - 1, 8 * i) }
86      when(wen) {
87        mem.write(wIdx, wdata, in.w.bits.strb.asBools())
88      }
89
90      Cat(mem.read(rIdx).reverse)
91    }
92    in.r.bits.data := rdata
93  }
94}
95
96class AXI4RAMWrapper
97(snode: AXI4SlaveNode, memByte: Long, useBlackBox: Boolean = false)
98(implicit p: Parameters)
99  extends LazyModule {
100
101  val mnode = AXI4MasterNode(List(snode.in.head._2.master))
102
103  val portParam = snode.portParams.head
104  val slaveParam = portParam.slaves.head
105  val burstLen = portParam.maxTransfer / portParam.beatBytes
106  val ram = LazyModule(new AXI4RAM(
107    slaveParam.address, memByte, useBlackBox,
108    slaveParam.executable, portParam.beatBytes, burstLen
109  ))
110  ram.node := mnode
111
112  val io_axi4 = InModuleBody{ mnode.makeIOs() }
113
114  lazy val module = new LazyModuleImp(this){}
115}
116