Files
Toooba/src_Core/CPU/LLC_AXI4_Adapter.bsv
Jonathan Woodruff 3ebf537f71 Tidy up tracing options, including using RVFI when building for bluesim
(which I'm sure we had meant to be doing?).
2023-06-23 13:09:38 +00:00

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//-
// RVFI_DII + CHERI modifications:
// Copyright (c) 2020 Alexandre Joannou
// Copyright (c) 2020 Jonathan Woodruff
// All rights reserved.
//
// This software was developed by SRI International and the University of
// Cambridge Computer Laboratory (Department of Computer Science and
// Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
// DARPA SSITH research programme.
//
// This work was supported by NCSC programme grant 4212611/RFA 15971 ("SafeBet").
//-
package LLC_AXI4_Adapter;
// ================================================================
// BSV lib imports
import ConfigReg :: *;
import Assert :: *;
import FIFOF :: *;
import Vector :: *;
// ----------------
// BSV additional libs
import GetPut_Aux :: *;
import Cur_Cycle :: *;
import Semi_FIFOF :: *;
import CreditCounter :: *;
// ================================================================
// Project imports
// ----------------
// From MIT RISCY-OOO
import Types :: *;
import CacheUtils :: *;
import CCTypes :: *;
// ----------------
// From Bluespec Pipes
import AXI4 :: *;
import SourceSink :: *;
import Fabric_Defs :: *;
import SoC_Map :: *;
import VnD :: *;
import Bag :: *;
import ProcTypes :: *;
// ================================================================
interface LLC_AXI4_Adapter_IFC;
method Action reset;
// Fabric master interface for memory
interface AXI4_Master #(Wd_MId, Wd_Addr, Wd_Data,
Wd_AW_User, Wd_W_User, Wd_B_User,
Wd_AR_User, Wd_R_User) mem_master;
endinterface
// ================================================================
typedef struct {
Bool tag_req; // meaningful to upgrade to E if toState is S
idT id; // slot id in child cache
childT child; // from which child
} LLC_AXI_ID#(type idT, type childT) deriving(Bits, Eq, FShow);
typedef 16 OutstandingWrites;
typedef 16 WriteAddressHashW;
module mkLLC_AXi4_Adapter #(MemFifoClient #(idT, childT) llc)
(LLC_AXI4_Adapter_IFC)
provisos(Bits#(idT, idSz),
Bits#(childT, childSz),
FShow#(ToMemMsg#(idT, childT)),
FShow#(MemRsMsg#(idT, childT)),
Add#(SizeOf#(Line), 0, TAdd#(512, 4)), // assert Line sz = 512 + 4 tags
Add#(a__, SizeOf#(LLC_AXI_ID#(idT, childT)), Wd_MId) // LLC_AXI_ID must fit into the external ID.
);
// Verbosity: 0: quiet; 1: LLC transactions; 2: loop detail
Integer verbosity = 0;
Reg #(Bit #(4)) cfg_verbosity <- mkConfigReg (fromInteger (verbosity));
// ================================================================
// Fabric request/response
let masterPortShim <- mkAXI4ShimFF;
// For discarding write-responses
CreditCounter_IFC #(TLog#(OutstandingWrites)) ctr_wr_rsps_pending <- mkCreditCounter; // 16 outstanding writes.
Bag#(OutstandingWrites, Bit#(Wd_MId), Bit#(WriteAddressHashW)) outstandingWrites <- mkSmallBag;
// ================================================================
// Functions to interact with the fabric
// Send a read-request into the fabric
function Action fa_fabric_send_read_req (Fabric_Addr addr, LLC_AXI_ID#(idT, childT) id);
action
Bit#(Wd_MId) arid = zeroExtend(pack(id));
let mem_req_rd_addr = AXI4_ARFlit {arid: arid,
araddr: addr,
arlen: 0, // burst len = arlen+1
arsize: id.tag_req ? 1 : 64,
arburst: INCR,
arlock: fabric_default_lock,
arcache: fabric_default_arcache,
arprot: fabric_default_prot,
arqos: fabric_default_qos,
arregion: fabric_default_region,
aruser: pack(id.tag_req)};
masterPortShim.slave.ar.put(mem_req_rd_addr);
// Debugging
if (cfg_verbosity > 1) begin
$display (" ", fshow (mem_req_rd_addr));
end
endaction
endfunction
// ================================================================
// Handle read requests and responses
rule rl_handle_read_req (llc.toM.first matches tagged Ld .ld &&& !outstandingWrites.dataMatch(hash(ld.addr[63:6])));
if ((cfg_verbosity > 0)) begin
$display ("%0d: LLC_AXI4_Adapter.rl_handle_read_req: Ld request from LLC to memory",
cur_cycle);
$display (" ", fshow (ld));
end
Addr line_addr = {ld.addr [63:6], 6'h0 }; // Addr of containing cache line
fa_fabric_send_read_req (line_addr, LLC_AXI_ID{tag_req: ld.tag_req, id: ld.id, child: ld.child});
llc.toM.deq;
endrule
rule rl_handle_read_rsps;
let mem_rsp <- get(masterPortShim.slave.r);
if (cfg_verbosity > 1) begin
$display ("%0d: LLC_AXI4_Adapter.rl_handle_read_rsps: ", cur_cycle);
$display (" ", fshow (mem_rsp));
end
if (mem_rsp.rresp != OKAY) begin
// TODO: need to raise a non-maskable interrupt (NMI) here
$display ("%0d: LLC_AXI4_Adapter.rl_handle_read_rsp: fabric response error; exit", cur_cycle);
$display (" ", fshow (mem_rsp));
$finish (1);
end
let new_cline = CLine { tag: unpack(mem_rsp.ruser)
, data: unpack(mem_rsp.rdata) };
LLC_AXI_ID#(idT, childT) id = unpack(truncate(mem_rsp.rid));
MemRsMsg #(idT, childT) resp = MemRsMsg {data: new_cline,
child: id.child,
id: id.id};
if (id.tag_req) begin
resp.data = CLine { tag: unpack(truncate(mem_rsp.rdata)), data: ?};
end
llc.rsFromM.enq (resp);
if (cfg_verbosity > 1)
$display (" Response to LLC: ", fshow (resp));
endrule
// ================================================================
// Handle write requests and responses
Reg#(Bit#(Wd_MId)) wid_reg <- mkRegU;
rule rl_handle_write_req (llc.toM.first matches tagged Wb .wb &&& !outstandingWrites.isMember(wid_reg).v);
if (cfg_verbosity > 0) begin
$display ("%d: LLC_AXI4_Adapter.rl_handle_write_req: Wb request from LLC to memory:", cur_cycle);
$display (" ", fshow (wb));
end
// send AXI4 AW flit
masterPortShim.slave.aw.put (AXI4_AWFlit {
awid: wid_reg,
awaddr: { wb.addr [63:6], 6'h0 },
awlen: 0, // burst len = awlen+1
awsize: 64,
awburst: INCR,
awlock: fabric_default_lock,
awcache: fabric_default_awcache,
awprot: fabric_default_prot,
awqos: fabric_default_qos,
awregion: fabric_default_region,
awuser: 0});
// Expect a fabric response
ctr_wr_rsps_pending.incr;
outstandingWrites.insert(wid_reg, hash(wb.addr[63:6]));
wid_reg <= wid_reg + 1; // Best effort to use unique IDs to allow reordering in the fabric.
llc.toM.deq;
Vector #(8, Bit #(8)) line_strb = unpack(pack(wb.byteEn));
Vector #(4, MemTaggedData) line_data = clineToMemTaggedDataVector(wb.data);
// send AXI4 W flit
masterPortShim.slave.w.put(AXI4_WFlit {
wdata: pack(wb.data.data),
wstrb: pack(wb.byteEn),
wlast: True,
wuser: pack(wb.data.tag)});
endrule
// ----------------
// Discard write-responses from the fabric
rule rl_discard_write_rsp;
let wr_resp <- get(masterPortShim.slave.b);
if (ctr_wr_rsps_pending.value == 0) begin
$display ("%0d: ERROR: LLC_AXI4_Adapter.rl_discard_write_rsp: unexpected Wr response (ctr_wr_rsps_pending.value == 0)",
cur_cycle);
$display (" ", fshow (wr_resp));
$finish (1); // Assertion failure
end
ctr_wr_rsps_pending.decr;
outstandingWrites.remove(wr_resp.bid);
if (wr_resp.bresp != OKAY) begin
// TODO: need to raise a non-maskable interrupt (NMI) here
$display ("%0d: LLC_AXI4_Adapter.rl_discard_write_rsp: fabric response error: exit", cur_cycle);
$display (" ", fshow (wr_resp));
$finish (1);
end
endrule
// ================================================================
// INTERFACE
method Action reset;
error("Reset called for LLC AXI4 adapter");
// XXX resetting this module would cause wedges unless the surrounding
// fabric was also fully reset
endmethod
// Fabric interface for memory
interface mem_master = masterPortShim.master;
endmodule
// ================================================================
endpackage