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//////////////////////////////////////////////////////////////////////
////                                                              ////
////  OR1200's DC FSM                                             ////
////                                                              ////
////  This file is part of the OpenRISC 1200 project              ////
////  http://www.opencores.org/cores/or1k/                        ////
////                                                              ////
////  Description                                                 ////
////  Data cache state machine                                    ////
////                                                              ////
////  To Do:                                                      ////
////   - make it smaller and faster                               ////
////                                                              ////
////  Author(s):                                                  ////
////      - Damjan Lampret, lampret@opencores.org                 ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2000 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// This source file may be used and distributed without         ////
//// restriction provided that this copyright statement is not    ////
//// removed from the file and that any derivative work contains  ////
//// the original copyright notice and the associated disclaimer. ////
////                                                              ////
//// This source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: not supported by cvs2svn $
// Revision 1.1.1.1  2002/03/21 16:55:45  lampret
// First import of the "new" XESS XSV environment.
//
//
// Revision 1.5  2002/02/11 04:33:17  lampret
// Speed optimizations (removed duplicate _cyc_ and _stb_). Fixed D/IMMU cache-inhibit attr.
//
// Revision 1.4  2002/02/01 19:56:54  lampret
// Fixed combinational loops.
//
// Revision 1.3  2002/01/28 01:15:59  lampret
// Changed 'void' nop-ops instead of insn[0] to use insn[16]. Debug unit stalls the tick timer. Prepared new flag generation for add and and insns. Blocked DC/IC while they are turned off. Fixed I/D MMU SPRs layout except WAYs. TODO: smart IC invalidate, l.j 2 and TLB ways.
//
// Revision 1.2  2002/01/14 06:18:22  lampret
// Fixed mem2reg bug in FAST implementation. Updated debug unit to work with new genpc/if.
//
// Revision 1.1  2002/01/03 08:16:15  lampret
// New prefixes for RTL files, prefixed module names. Updated cache controllers and MMUs.
//
// Revision 1.9  2001/10/21 17:57:16  lampret
// Removed params from generic_XX.v. Added translate_off/on in sprs.v and id.v. Removed spr_addr from dc.v and ic.v. Fixed CR+LF.
//
// Revision 1.8  2001/10/19 23:28:46  lampret
// Fixed some synthesis warnings. Configured with caches and MMUs.
//
// Revision 1.7  2001/10/14 13:12:09  lampret
// MP3 version.
//
// Revision 1.1.1.1  2001/10/06 10:18:35  igorm
// no message
//
// Revision 1.2  2001/08/09 13:39:33  lampret
// Major clean-up.
//
// Revision 1.1  2001/07/20 00:46:03  lampret
// Development version of RTL. Libraries are missing.
//
//
 
// synopsys translate_off
`include "timescale.v"
// synopsys translate_on
`include "or1200_defines.v"
 
`define OR1200_DCFSM_IDLE       3'd0
`define OR1200_DCFSM_CLOAD      3'd1
`define OR1200_DCFSM_LREFILL3   3'd2
`define OR1200_DCFSM_CSTORE     3'd3
`define OR1200_DCFSM_SREFILL4   3'd4
`define OR1200_DCFSM_ILOAD      3'd5
`define OR1200_DCFSM_ISTORE     3'd6
 
//
// Data cache FSM for cache line of 16 bytes (4x singleword)
//
 
module or1200_dc_fsm(
        // Clock and reset
        clk, rst,
 
        // Internal i/f to top level DC
        dc_en, dcdmmu_cycstb_i, dcdmmu_ci_i, dcpu_we_i, dcpu_sel_i,
        tagcomp_miss, biudata_valid, biudata_error, start_addr, saved_addr,
        dcram_we, biu_read, biu_write, first_hit_ack, first_miss_ack, first_miss_err,
        burst, tag_we, dc_addr
);
 
//
// I/O
//
input                           clk;
input                           rst;
input                           dc_en;
input                           dcdmmu_cycstb_i;
input                           dcdmmu_ci_i;
input                           dcpu_we_i;
input   [3:0]                    dcpu_sel_i;
input                           tagcomp_miss;
input                           biudata_valid;
input                           biudata_error;
input   [31:0]                   start_addr;
output  [31:0]                   saved_addr;
output  [3:0]                    dcram_we;
output                          biu_read;
output                          biu_write;
output                          first_hit_ack;
output                          first_miss_ack;
output                          first_miss_err;
output                          burst;
output                          tag_we;
output  [31:0]                   dc_addr;
 
//
// Internal wires and regs
//
reg     [31:0]                   saved_addr_r;
reg     [2:0]                    state;
reg     [2:0]                    cnt;
reg                             hitmiss_eval;
reg                             store;
reg                             load;
reg                             cache_inhibit;
wire                            first_store_hit_ack;
 
//
// Generate of DCRAM write enables
//
assign dcram_we = {4{load & biudata_valid & !cache_inhibit}} | {4{first_store_hit_ack}} & dcpu_sel_i;
assign tag_we = biu_read & biudata_valid & !cache_inhibit;
 
//
// BIU read and write
//
assign biu_read = (hitmiss_eval & tagcomp_miss) | (!hitmiss_eval & load);
assign biu_write = store;
 
assign dc_addr = (biu_read | biu_write) & !hitmiss_eval ? saved_addr : start_addr;
assign saved_addr = saved_addr_r;
 
//
// Assert for cache hit first word ready
// Assert for store cache hit first word ready
// Assert for cache miss first word stored/loaded OK
// Assert for cache miss first word stored/loaded with an error
//
assign first_hit_ack = (state == `OR1200_DCFSM_CLOAD) & !tagcomp_miss & !cache_inhibit & !dcdmmu_ci_i | first_store_hit_ack;
assign first_store_hit_ack = (state == `OR1200_DCFSM_CSTORE) & !tagcomp_miss & biudata_valid & !cache_inhibit & !dcdmmu_ci_i;
assign first_miss_ack = ((state == `OR1200_DCFSM_CLOAD) | (state == `OR1200_DCFSM_CSTORE)) & biudata_valid;
assign first_miss_err = ((state == `OR1200_DCFSM_CLOAD) | (state == `OR1200_DCFSM_CSTORE)) & biudata_error;
 
//
// Assert burst when doing reload of complete cache line
//
assign burst = (state == `OR1200_DCFSM_CLOAD) & tagcomp_miss & !cache_inhibit
                | (state == `OR1200_DCFSM_LREFILL3)
`ifdef OR1200_DC_STORE_REFILL
                | (state == `OR1200_DCFSM_SREFILL4)
`endif
                ;
 
//
// Main DC FSM
//
always @(posedge clk or posedge rst) begin
        if (rst) begin
                state <= #1 `OR1200_DCFSM_IDLE;
                saved_addr_r <= #1 32'b0;
                hitmiss_eval <= #1 1'b0;
                store <= #1 1'b0;
                load <= #1 1'b0;
                cnt <= #1 3'b000;
                cache_inhibit <= #1 1'b0;
        end
        else
        case (state)    // synopsys parallel_case
                `OR1200_DCFSM_IDLE :
                        if (dc_en & dcdmmu_cycstb_i & dcpu_we_i) begin  // store
                                state <= #1 `OR1200_DCFSM_CSTORE;
                                saved_addr_r <= #1 start_addr;
                                hitmiss_eval <= #1 1'b1;
                                store <= #1 1'b1;
                                load <= #1 1'b0;
                                cache_inhibit <= #1 1'b0;
                        end
                        else if (dc_en & dcdmmu_cycstb_i) begin         // load
                                state <= #1 `OR1200_DCFSM_CLOAD;
                                saved_addr_r <= #1 start_addr;
                                hitmiss_eval <= #1 1'b1;
                                store <= #1 1'b0;
                                load <= #1 1'b1;
                                cache_inhibit <= #1 1'b0;
                        end
                        else begin                                                      // idle
                                hitmiss_eval <= #1 1'b0;
                                store <= #1 1'b0;
                                load <= #1 1'b0;
                                cache_inhibit <= #1 1'b0;
                        end
                `OR1200_DCFSM_CLOAD: begin              // load
                        if (dcdmmu_cycstb_i & dcdmmu_ci_i)
                                cache_inhibit <= #1 1'b1;
                        if (hitmiss_eval)
                                saved_addr_r[31:13] <= #1 start_addr[31:13];
                        if ((hitmiss_eval & !dcdmmu_cycstb_i) ||                                        // load aborted (usually caused by DMMU)
                            (biudata_error) ||                                                                          // load terminated with an error
                            ((cache_inhibit | dcdmmu_ci_i) & biudata_valid)) begin      // load from cache-inhibited area
                                state <= #1 `OR1200_DCFSM_IDLE;
                                hitmiss_eval <= #1 1'b0;
                                load <= #1 1'b0;
                                cache_inhibit <= #1 1'b0;
                        end
                        else if (tagcomp_miss & biudata_valid) begin    // load missed, finish current external load and refill
                                state <= #1 `OR1200_DCFSM_LREFILL3;
                                saved_addr_r[3:2] <= #1 saved_addr_r[3:2] + 'd1;
                                hitmiss_eval <= #1 1'b0;
                                cnt <= #1 `OR1200_DCLS-2;
                                cache_inhibit <= #1 1'b0;
                        end
                        else if (!tagcomp_miss & !dcdmmu_ci_i) begin    // load hit, finish immediately
                                state <= #1 `OR1200_DCFSM_IDLE;
                                hitmiss_eval <= #1 1'b0;
                                load <= #1 1'b0;
                                cache_inhibit <= #1 1'b0;
                        end
                        else                                            // load in-progress
                                hitmiss_eval <= #1 1'b0;
                end
                `OR1200_DCFSM_LREFILL3 : begin
                        if (biudata_valid && (|cnt)) begin              // refill ack, more loads to come
                                cnt <= #1 cnt - 'd1;
                                saved_addr_r[3:2] <= #1 saved_addr_r[3:2] + 'd1;
                        end
                        else if (biudata_valid) begin                   // last load of line refill
                                state <= #1 `OR1200_DCFSM_IDLE;
                                load <= #1 1'b0;
                        end
                end
                `OR1200_DCFSM_CSTORE: begin             // store
                        if (dcdmmu_cycstb_i & dcdmmu_ci_i)
                                cache_inhibit <= #1 1'b1;
                        if (hitmiss_eval)
                                saved_addr_r[31:13] <= #1 start_addr[31:13];
                        if ((hitmiss_eval & !dcdmmu_cycstb_i) ||        // store aborted (usually caused by DMMU)
                            (biudata_error) ||                                          // store terminated with an error
                            ((cache_inhibit | dcdmmu_ci_i) & biudata_valid)) begin      // store to cache-inhibited area
                                state <= #1 `OR1200_DCFSM_IDLE;
                                hitmiss_eval <= #1 1'b0;
                                store <= #1 1'b0;
                                cache_inhibit <= #1 1'b0;
                        end
`ifdef OR1200_DC_STORE_REFILL
                        else if (tagcomp_miss & biudata_valid) begin    // store missed, finish write-through and do load refill
                                state <= #1 `OR1200_DCFSM_SREFILL4;
                                hitmiss_eval <= #1 1'b0;
                                store <= #1 1'b0;
                                load <= #1 1'b1;
                                cnt <= #1 `OR1200_DCLS-1;
                                cache_inhibit <= #1 1'b0;
                        end
`endif
                        else if (biudata_valid) begin                   // store hit, finish write-through
                                state <= #1 `OR1200_DCFSM_IDLE;
                                hitmiss_eval <= #1 1'b0;
                                store <= #1 1'b0;
                                cache_inhibit <= #1 1'b0;
                        end
                        else                                            // store write-through in-progress
                                hitmiss_eval <= #1 1'b0;
                        end
`ifdef OR1200_DC_STORE_REFILL
                `OR1200_DCFSM_SREFILL4 : begin
                        if (biudata_valid && (|cnt)) begin              // refill ack, more loads to come
                                cnt <= #1 cnt - 'd1;
                                saved_addr_r[3:2] <= #1 saved_addr_r[3:2] + 'd1;
                        end
                        else if (biudata_valid) begin                   // last load of line refill
                                state <= #1 `OR1200_DCFSM_IDLE;
                                load <= #1 1'b0;
                        end
                end
`endif
                default:
                        state <= #1 `OR1200_DCFSM_IDLE;
        endcase
end
 
endmodule

Line No.	Rev	Author	Line
1	504	lampret	`//////////////////////////////////////////////////////////////////////`
2			`//// ////`
3			`//// OR1200's DC FSM ////`
4			`//// ////`
5			`//// This file is part of the OpenRISC 1200 project ////`
6			`//// http://www.opencores.org/cores/or1k/ ////`
7			`//// ////`
8			`//// Description ////`
9			`//// Data cache state machine ////`
10			`//// ////`
11			`//// To Do: ////`
12			`//// - make it smaller and faster ////`
13			`//// ////`
14			`//// Author(s): ////`
15			`//// - Damjan Lampret, lampret@opencores.org ////`
16			`//// ////`
17			`//////////////////////////////////////////////////////////////////////`
18			`//// ////`
19			`//// Copyright (C) 2000 Authors and OPENCORES.ORG ////`
20			`//// ////`
21			`//// This source file may be used and distributed without ////`
22			`//// restriction provided that this copyright statement is not ////`
23			`//// removed from the file and that any derivative work contains ////`
24			`//// the original copyright notice and the associated disclaimer. ////`
25			`//// ////`
26			`//// This source file is free software; you can redistribute it ////`
27			`//// and/or modify it under the terms of the GNU Lesser General ////`
28			`//// Public License as published by the Free Software Foundation; ////`
29			`//// either version 2.1 of the License, or (at your option) any ////`
30			`//// later version. ////`
31			`//// ////`
32			`//// This source is distributed in the hope that it will be ////`
33			`//// useful, but WITHOUT ANY WARRANTY; without even the implied ////`
34			`//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR ////`
35			`//// PURPOSE. See the GNU Lesser General Public License for more ////`
36			`//// details. ////`
37			`//// ////`
38			`//// You should have received a copy of the GNU Lesser General ////`
39			`//// Public License along with this source; if not, download it ////`
40			`//// from http://www.opencores.org/lgpl.shtml ////`
41			`//// ////`
42			`//////////////////////////////////////////////////////////////////////`
43			`//`
44			`// CVS Revision History`
45			`//`
46			`// $Log: not supported by cvs2svn $`
47	775	lampret	`// Revision 1.1.1.1 2002/03/21 16:55:45 lampret`
48			`// First import of the "new" XESS XSV environment.`
49			`//`
50			`//`
51			`// Revision 1.5 2002/02/11 04:33:17 lampret`
52			`// Speed optimizations (removed duplicate _cyc_ and _stb_). Fixed D/IMMU cache-inhibit attr.`
53			`//`
54	660	lampret	`// Revision 1.4 2002/02/01 19:56:54 lampret`
55			`// Fixed combinational loops.`
56			`//`
57	636	lampret	`// Revision 1.3 2002/01/28 01:15:59 lampret`
58			`// Changed 'void' nop-ops instead of insn[0] to use insn[16]. Debug unit stalls the tick timer. Prepared new flag generation for add and and insns. Blocked DC/IC while they are turned off. Fixed I/D MMU SPRs layout except WAYs. TODO: smart IC invalidate, l.j 2 and TLB ways.`
59			`//`
60	617	lampret	`// Revision 1.2 2002/01/14 06:18:22 lampret`
61			`// Fixed mem2reg bug in FAST implementation. Updated debug unit to work with new genpc/if.`
62			`//`
63	562	lampret	`// Revision 1.1 2002/01/03 08:16:15 lampret`
64			`// New prefixes for RTL files, prefixed module names. Updated cache controllers and MMUs.`
65			`//`
66	504	lampret	`// Revision 1.9 2001/10/21 17:57:16 lampret`
67			`// Removed params from generic_XX.v. Added translate_off/on in sprs.v and id.v. Removed spr_addr from dc.v and ic.v. Fixed CR+LF.`
68			`//`
69			`// Revision 1.8 2001/10/19 23:28:46 lampret`
70			`// Fixed some synthesis warnings. Configured with caches and MMUs.`
71			`//`
72			`// Revision 1.7 2001/10/14 13:12:09 lampret`
73			`// MP3 version.`
74			`//`
75			`// Revision 1.1.1.1 2001/10/06 10:18:35 igorm`
76			`// no message`
77			`//`
78			`// Revision 1.2 2001/08/09 13:39:33 lampret`
79			`// Major clean-up.`
80			`//`
81			`// Revision 1.1 2001/07/20 00:46:03 lampret`
82			`// Development version of RTL. Libraries are missing.`
83			`//`
84			`//`
85
86			`// synopsys translate_off`
87			`include "timescale.v"
88			`// synopsys translate_on`
89			`include "or1200_defines.v"
90
91			`define OR1200_DCFSM_IDLE 3'd0
92	636	lampret	`define OR1200_DCFSM_CLOAD 3'd1
93	504	lampret	`define OR1200_DCFSM_LREFILL3 3'd2
94	636	lampret	`define OR1200_DCFSM_CSTORE 3'd3
95	504	lampret	`define OR1200_DCFSM_SREFILL4 3'd4
96	636	lampret	`define OR1200_DCFSM_ILOAD 3'd5
97			`define OR1200_DCFSM_ISTORE 3'd6
98	504	lampret
99			`//`
100			`// Data cache FSM for cache line of 16 bytes (4x singleword)`
101			`//`
102
103			`module or1200_dc_fsm(`
104			`// Clock and reset`
105			`clk, rst,`
106
107			`// Internal i/f to top level DC`
108	660	lampret	`dc_en, dcdmmu_cycstb_i, dcdmmu_ci_i, dcpu_we_i, dcpu_sel_i,`
109	504	lampret	`tagcomp_miss, biudata_valid, biudata_error, start_addr, saved_addr,`
110			`dcram_we, biu_read, biu_write, first_hit_ack, first_miss_ack, first_miss_err,`
111	660	lampret	`burst, tag_we, dc_addr`
112	504	lampret	`);`
113
114			`//`
115			`// I/O`
116			`//`
117			`input clk;`
118			`input rst;`
119			`input dc_en;`
120	660	lampret	`input dcdmmu_cycstb_i;`
121	504	lampret	`input dcdmmu_ci_i;`
122			`input dcpu_we_i;`
123			`input [3:0] dcpu_sel_i;`
124			`input tagcomp_miss;`
125			`input biudata_valid;`
126			`input biudata_error;`
127			`input [31:0] start_addr;`
128			`output [31:0] saved_addr;`
129			`output [3:0] dcram_we;`
130			`output biu_read;`
131			`output biu_write;`
132			`output first_hit_ack;`
133			`output first_miss_ack;`
134			`output first_miss_err;`
135			`output burst;`
136	660	lampret	`output tag_we;`
137			`output [31:0] dc_addr;`
138	504	lampret
139			`//`
140			`// Internal wires and regs`
141			`//`
142	660	lampret	`reg [31:0] saved_addr_r;`
143	504	lampret	`reg [2:0] state;`
144			`reg [2:0] cnt;`
145			`reg hitmiss_eval;`
146			`reg store;`
147			`reg load;`
148	660	lampret	`reg cache_inhibit;`
149	636	lampret	`wire first_store_hit_ack;`
150	504	lampret
151			`//`
152			`// Generate of DCRAM write enables`
153			`//`
154	660	lampret	`assign dcram_we = {4{load & biudata_valid & !cache_inhibit}} \| {4{first_store_hit_ack}} & dcpu_sel_i;`
155			`assign tag_we = biu_read & biudata_valid & !cache_inhibit;`
156	504	lampret
157			`//`
158			`// BIU read and write`
159			`//`
160			`assign biu_read = (hitmiss_eval & tagcomp_miss) \| (!hitmiss_eval & load);`
161			`assign biu_write = store;`
162
163	660	lampret	`assign dc_addr = (biu_read \| biu_write) & !hitmiss_eval ? saved_addr : start_addr;`
164			`assign saved_addr = saved_addr_r;`
165
166	504	lampret	`//`
167			`// Assert for cache hit first word ready`
168	636	lampret	`// Assert for store cache hit first word ready`
169	504	lampret	`// Assert for cache miss first word stored/loaded OK`
170			`// Assert for cache miss first word stored/loaded with an error`
171			`//`
172	660	lampret	assign first_hit_ack = (state == `OR1200_DCFSM_CLOAD) & !tagcomp_miss & !cache_inhibit & !dcdmmu_ci_i \| first_store_hit_ack;
173			assign first_store_hit_ack = (state == `OR1200_DCFSM_CSTORE) & !tagcomp_miss & biudata_valid & !cache_inhibit & !dcdmmu_ci_i;
174			assign first_miss_ack = ((state == `OR1200_DCFSM_CLOAD) \| (state == `OR1200_DCFSM_CSTORE)) & biudata_valid;
175			assign first_miss_err = ((state == `OR1200_DCFSM_CLOAD) \| (state == `OR1200_DCFSM_CSTORE)) & biudata_error;
176	504	lampret
177			`//`
178			`// Assert burst when doing reload of complete cache line`
179			`//`
180	660	lampret	assign burst = (state == `OR1200_DCFSM_CLOAD) & tagcomp_miss & !cache_inhibit
181	636	lampret	\| (state == `OR1200_DCFSM_LREFILL3)
182			`ifdef OR1200_DC_STORE_REFILL
183			\| (state == `OR1200_DCFSM_SREFILL4)
184			`endif
185			`;`
186	504	lampret
187			`//`
188			`// Main DC FSM`
189			`//`
190			`always @(posedge clk or posedge rst) begin`
191			`if (rst) begin`
192			state <= #1 `OR1200_DCFSM_IDLE;
193	660	lampret	`saved_addr_r <= #1 32'b0;`
194	504	lampret	`hitmiss_eval <= #1 1'b0;`
195			`store <= #1 1'b0;`
196			`load <= #1 1'b0;`
197			`cnt <= #1 3'b000;`
198	660	lampret	`cache_inhibit <= #1 1'b0;`
199	504	lampret	`end`
200			`else`
201			`case (state) // synopsys parallel_case`
202			`OR1200_DCFSM_IDLE :
203	660	lampret	`if (dc_en & dcdmmu_cycstb_i & dcpu_we_i) begin // store`
204	636	lampret	state <= #1 `OR1200_DCFSM_CSTORE;
205	660	lampret	`saved_addr_r <= #1 start_addr;`
206	504	lampret	`hitmiss_eval <= #1 1'b1;`
207			`store <= #1 1'b1;`
208			`load <= #1 1'b0;`
209	660	lampret	`cache_inhibit <= #1 1'b0;`
210	504	lampret	`end`
211	660	lampret	`else if (dc_en & dcdmmu_cycstb_i) begin // load`
212	636	lampret	state <= #1 `OR1200_DCFSM_CLOAD;
213	660	lampret	`saved_addr_r <= #1 start_addr;`
214	504	lampret	`hitmiss_eval <= #1 1'b1;`
215			`store <= #1 1'b0;`
216			`load <= #1 1'b1;`
217	660	lampret	`cache_inhibit <= #1 1'b0;`
218	504	lampret	`end`
219			`else begin // idle`
220			`hitmiss_eval <= #1 1'b0;`
221			`store <= #1 1'b0;`
222			`load <= #1 1'b0;`
223	660	lampret	`cache_inhibit <= #1 1'b0;`
224	504	lampret	`end`
225	660	lampret	`OR1200_DCFSM_CLOAD: begin // load
226			`if (dcdmmu_cycstb_i & dcdmmu_ci_i)`
227			`cache_inhibit <= #1 1'b1;`
228			`if (hitmiss_eval)`
229			`saved_addr_r[31:13] <= #1 start_addr[31:13];`
230	775	lampret	`if ((hitmiss_eval & !dcdmmu_cycstb_i) \|\| // load aborted (usually caused by DMMU)`
231			`(biudata_error) \|\| // load terminated with an error`
232			`((cache_inhibit \| dcdmmu_ci_i) & biudata_valid)) begin // load from cache-inhibited area`
233	504	lampret	state <= #1 `OR1200_DCFSM_IDLE;
234			`hitmiss_eval <= #1 1'b0;`
235			`load <= #1 1'b0;`
236	660	lampret	`cache_inhibit <= #1 1'b0;`
237	504	lampret	`end`
238			`else if (tagcomp_miss & biudata_valid) begin // load missed, finish current external load and refill`
239			state <= #1 `OR1200_DCFSM_LREFILL3;
240	660	lampret	`saved_addr_r[3:2] <= #1 saved_addr_r[3:2] + 'd1;`
241	504	lampret	`hitmiss_eval <= #1 1'b0;`
242			cnt <= #1 `OR1200_DCLS-2;
243	660	lampret	`cache_inhibit <= #1 1'b0;`
244	504	lampret	`end`
245	660	lampret	`else if (!tagcomp_miss & !dcdmmu_ci_i) begin // load hit, finish immediately`
246	504	lampret	state <= #1 `OR1200_DCFSM_IDLE;
247			`hitmiss_eval <= #1 1'b0;`
248			`load <= #1 1'b0;`
249	660	lampret	`cache_inhibit <= #1 1'b0;`
250	504	lampret	`end`
251			`else // load in-progress`
252			`hitmiss_eval <= #1 1'b0;`
253	660	lampret	`end`
254	504	lampret	`OR1200_DCFSM_LREFILL3 : begin
255	775	lampret	`if (biudata_valid && (\|cnt)) begin // refill ack, more loads to come`
256	504	lampret	`cnt <= #1 cnt - 'd1;`
257	660	lampret	`saved_addr_r[3:2] <= #1 saved_addr_r[3:2] + 'd1;`
258	504	lampret	`end`
259			`else if (biudata_valid) begin // last load of line refill`
260			state <= #1 `OR1200_DCFSM_IDLE;
261			`load <= #1 1'b0;`
262			`end`
263			`end`
264	660	lampret	`OR1200_DCFSM_CSTORE: begin // store
265			`if (dcdmmu_cycstb_i & dcdmmu_ci_i)`
266			`cache_inhibit <= #1 1'b1;`
267			`if (hitmiss_eval)`
268			`saved_addr_r[31:13] <= #1 start_addr[31:13];`
269	775	lampret	`if ((hitmiss_eval & !dcdmmu_cycstb_i) \|\| // store aborted (usually caused by DMMU)`
270			`(biudata_error) \|\| // store terminated with an error`
271			`((cache_inhibit \| dcdmmu_ci_i) & biudata_valid)) begin // store to cache-inhibited area`
272	504	lampret	state <= #1 `OR1200_DCFSM_IDLE;
273			`hitmiss_eval <= #1 1'b0;`
274			`store <= #1 1'b0;`
275	660	lampret	`cache_inhibit <= #1 1'b0;`
276	504	lampret	`end`
277	636	lampret	`ifdef OR1200_DC_STORE_REFILL
278	504	lampret	`else if (tagcomp_miss & biudata_valid) begin // store missed, finish write-through and do load refill`
279			state <= #1 `OR1200_DCFSM_SREFILL4;
280			`hitmiss_eval <= #1 1'b0;`
281			`store <= #1 1'b0;`
282			`load <= #1 1'b1;`
283			cnt <= #1 `OR1200_DCLS-1;
284	660	lampret	`cache_inhibit <= #1 1'b0;`
285	504	lampret	`end`
286	636	lampret	`endif
287	504	lampret	`else if (biudata_valid) begin // store hit, finish write-through`
288			state <= #1 `OR1200_DCFSM_IDLE;
289			`hitmiss_eval <= #1 1'b0;`
290			`store <= #1 1'b0;`
291	660	lampret	`cache_inhibit <= #1 1'b0;`
292	504	lampret	`end`
293			`else // store write-through in-progress`
294			`hitmiss_eval <= #1 1'b0;`
295	660	lampret	`end`
296	636	lampret	`ifdef OR1200_DC_STORE_REFILL
297	504	lampret	`OR1200_DCFSM_SREFILL4 : begin
298	775	lampret	`if (biudata_valid && (\|cnt)) begin // refill ack, more loads to come`
299	504	lampret	`cnt <= #1 cnt - 'd1;`
300	660	lampret	`saved_addr_r[3:2] <= #1 saved_addr_r[3:2] + 'd1;`
301	504	lampret	`end`
302			`else if (biudata_valid) begin // last load of line refill`
303			state <= #1 `OR1200_DCFSM_IDLE;
304			`load <= #1 1'b0;`
305			`end`
306			`end`
307	636	lampret	`endif
308	504	lampret	`default:`
309			state <= #1 `OR1200_DCFSM_IDLE;
310			`endcase`
311			`end`
312
313			`endmodule`

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