xref: /XiangShan/src/main/scala/xiangshan/backend/fu/util/CSRConst.scala (revision 914bbc865acb565ce0fae9e50a787f2ab3c57b3a)
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 xiangshan.backend.fu.util
18
19import chisel3._
20import chisel3.util._
21import freechips.rocketchip.rocket.CSRs
22
23trait HasCSRConst {
24  // Supervisor Custom Read/Write
25  val Sbpctl        = 0x5C0
26  val Spfctl        = 0x5C1
27  val Slvpredctl    = 0x5C2
28  val Smblockctl    = 0x5C3
29  val Srnctl        = 0x5C4
30  /** 0x5C5-0x5E5 for cache instruction register*/
31  val Scachebase    = 0x5C5
32
33  // Machine level PMA TODO: remove this
34  val PmacfgBase    = 0x7C0
35  val PmaaddrBase   = 0x7C8 // 64 entry at most
36
37  def privEcall  = 0x000.U
38  def privEbreak = 0x001.U
39  def privMNret  = 0x702.U
40  def privMret   = 0x302.U
41  def privSret   = 0x102.U
42  def privUret   = 0x002.U
43  def privDret   = 0x7b2.U
44
45  def ModeM     = 0x3.U
46  def ModeH     = 0x2.U
47  def ModeS     = 0x1.U
48  def ModeU     = 0x0.U
49
50  def IRQ_USIP  = 0
51  def IRQ_SSIP  = 1
52  def IRQ_VSSIP = 2
53  def IRQ_MSIP  = 3
54
55  def IRQ_UTIP  = 4
56  def IRQ_STIP  = 5
57  def IRQ_VSTIP = 6
58  def IRQ_MTIP  = 7
59
60  def IRQ_UEIP  = 8
61  def IRQ_SEIP  = 9
62  def IRQ_VSEIP = 10
63  def IRQ_MEIP  = 11
64
65  def IRQ_SGEIP = 12
66  def IRQ_DEBUG = 17
67
68  val Hgatp_Mode_len = 4
69  val Hgatp_Vmid_len = 16
70  val Hgatp_Addr_len = 44
71
72  val Satp_Mode_len = 4
73  val Satp_Asid_len = 16
74  val Satp_Addr_len = 44
75  def satp_part_wmask(max_length: Int, length: Int) : UInt = {
76    require(length > 0 && length <= max_length)
77    ((1L << length) - 1).U(max_length.W)
78  }
79
80  val IntPriority = Seq(
81    IRQ_DEBUG,
82    IRQ_MEIP, IRQ_MSIP, IRQ_MTIP,
83    IRQ_SEIP, IRQ_SSIP, IRQ_STIP,
84    IRQ_UEIP, IRQ_USIP, IRQ_UTIP,
85    IRQ_VSEIP, IRQ_VSSIP, IRQ_VSTIP, IRQ_SGEIP
86  )
87
88  def csrAccessPermissionCheck(addr: UInt, wen: Bool, mode: UInt, virt: Bool, hasH: Bool): UInt = {
89    val readOnly = addr(11, 10) === "b11".U
90    val lowestAccessPrivilegeLevel = addr(9,8)
91    val priv = Mux(mode === ModeS, ModeH, mode)
92    val ret = Wire(Bool()) //0.U: normal, 1.U: illegal_instruction, 2.U: virtual instruction
93    when (lowestAccessPrivilegeLevel === ModeH && !hasH){
94      ret := 1.U
95    }.elsewhen (readOnly && wen) {
96      ret := 1.U
97    }.elsewhen (priv < lowestAccessPrivilegeLevel) {
98      when(virt && lowestAccessPrivilegeLevel <= ModeH){
99        ret := 2.U
100      }.otherwise{
101        ret := 1.U
102      }
103    }.otherwise{
104      ret := 0.U
105    }
106    ret
107  }
108
109  def perfcntPermissionCheck(addr: UInt, mode: UInt, mmask: UInt, smask: UInt): Bool = {
110    val index = UIntToOH(addr & 31.U)
111    Mux(mode === ModeM, true.B, Mux(mode === ModeS, (index & mmask) =/= 0.U, (index & mmask & smask) =/= 0.U))
112  }
113
114  def dcsrPermissionCheck(addr: UInt, mModeCanWrite: UInt, debug: Bool): Bool = {
115    // debug mode write only regs
116    val isDebugReg = addr(11, 4) === "h7b".U
117    Mux(!mModeCanWrite && isDebugReg, debug, true.B)
118  }
119
120  def triggerPermissionCheck(addr: UInt, mModeCanWrite: UInt, debug: Bool): Bool = {
121    val isTriggerReg = addr(11, 4) === "h7a".U
122    Mux(!mModeCanWrite && isTriggerReg, debug, true.B)
123  }
124}
125object CSRConst extends HasCSRConst
126