xref: /XiangShan/src/main/scala/device/AXI4Flash.scala (revision b4cc98d2e1083036b70daa90cb1a11c8302784f6)
1package device
2
3import chisel3._
4import chisel3.util._
5
6import bus.axi4._
7import utils._
8
9class AXI4Flash extends AXI4SlaveModule(new AXI4Lite) {
10  val jmpToDramInstr1 = "h0010029b".U  // addiw t0,zero,1
11  val jmpToDramInstr2 = "h01f29293".U  // slli  t0,t0,0x1f
12  val jmpToDramInstr3 = "h00028067".U  // jr t0
13
14  val mapping = Map(
15    RegMap(0x0, jmpToDramInstr1, RegMap.Unwritable),
16    RegMap(0x4, jmpToDramInstr2, RegMap.Unwritable),
17    RegMap(0x8, jmpToDramInstr3, RegMap.Unwritable)
18  )
19  def getOffset(addr: UInt) = addr(12,0)
20
21  val rdata = Wire(UInt())
22  RegMap.generate(mapping, getOffset(raddr), rdata,
23    getOffset(waddr), in.w.fire(), in.w.bits.data, MaskExpand(in.w.bits.strb))
24
25  in.r.bits.data := RegEnable(RegNext(rdata), ren)
26}
27