Subversion Repositories or1200_hp

//////////////////////////////////////////////////////////////////////
////                                                              ////
////  OR1200's register file inside CPU                           ////
////                                                              ////
////  This file is part of the OpenRISC 1200 project              ////
////  http://www.opencores.org/cores/or1k/                        ////
////                                                              ////
////  Description                                                 ////
////  Instantiation of register file memories                     ////
////                                                              ////
////  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 1.2  2002/06/08 16:19:09  lampret
// Added generic flip-flop based memory macro instantiation.
//
// Revision 1.1  2002/01/03 08:16:15  lampret
// New prefixes for RTL files, prefixed module names. Updated cache controllers and MMUs.
//
// Revision 1.13  2001/11/20 18:46:15  simons
// Break point bug fixed
//
// Revision 1.12  2001/11/13 10:02:21  lampret
// Added 'setpc'. Renamed some signals (except_flushpipe into flushpipe etc)
//
// Revision 1.11  2001/11/12 01:45:40  lampret
// Moved flag bit into SR. Changed RF enable from constant enable to dynamic enable for read ports.
//
// Revision 1.10  2001/11/10 03:43:57  lampret
// Fixed exceptions.
//
// 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  2001/10/14 13:12:10  lampret
// MP3 version.
//
// Revision 1.1.1.1  2001/10/06 10:18:36  igorm
// no message
//
// Revision 1.3  2001/08/09 13:39:33  lampret
// Major clean-up.
//
// Revision 1.2  2001/07/22 03:31:54  lampret
// Fixed RAM's oen bug. Cache bypass under development.
//
// Revision 1.1  2001/07/20 00:46:21  lampret
// Development version of RTL. Libraries are missing.
//
//
 
// synopsys translate_off
`include "timescale.v"
// synopsys translate_on
`include "or1200_defines.v"
 
module or1200_rf_cm4(
		clk_i_cml_1,
		clk_i_cml_2,
		clk_i_cml_3,
		cmls,
 
	// Clock and reset
	clk, rst,
 
	// Write i/f
	supv, wb_freeze, addrw, dataw, we, flushpipe,
 
	// Read i/f
	id_freeze, addra, addrb, dataa, datab, rda, rdb,
 
	// Debug
	spr_cs, spr_write, spr_addr, spr_dat_i, spr_dat_o
);
 
 
input clk_i_cml_1;
input clk_i_cml_2;
input clk_i_cml_3;
input [1:0] cmls;
reg  wb_freeze_cml_3;
reg [ 5 - 1 : 0 ] addrw_cml_2;
reg [ 5 - 1 : 0 ] addrw_cml_1;
reg [ 32 - 1 : 0 ] dataw_cml_3;
reg  spr_write_cml_3;
reg  spr_write_cml_2;
reg  spr_write_cml_1;
reg [ 31 : 0 ] spr_addr_cml_3;
reg [ 31 : 0 ] spr_addr_cml_2;
reg [ 31 : 0 ] spr_addr_cml_1;
reg [ 31 : 0 ] spr_dat_i_cml_3;
reg [ 31 : 0 ] spr_dat_i_cml_2;
reg [ 31 : 0 ] spr_dat_i_cml_1;
reg [ 32 - 1 : 0 ] from_rfa_cml_3;
reg [ 32 - 1 : 0 ] from_rfa_cml_2;
reg [ 32 : 0 ] dataa_saved_cml_3;
reg [ 32 : 0 ] dataa_saved_cml_2;
reg [ 32 : 0 ] dataa_saved_cml_1;
reg [ 32 : 0 ] datab_saved_cml_3;
reg [ 32 : 0 ] datab_saved_cml_2;
reg [ 32 : 0 ] datab_saved_cml_1;
reg [ 5 - 1 : 0 ] rf_addrw_cml_3;
reg  spr_valid_cml_3;
reg  rf_we_allow_cml_3;
reg  rf_we_allow_cml_2;
reg  rf_we_allow_cml_1;
reg [ 32 - 1 : 0 ] from_rfa_int_cml_1;
reg [ 32 - 1 : 0 ] from_rfb_int_cml_3;
reg [ 32 - 1 : 0 ] from_rfb_int_cml_2;
reg [ 32 - 1 : 0 ] from_rfb_int_cml_1;
reg [ 4 : 0 ] rf_addra_reg_cml_3;
reg [ 4 : 0 ] rf_addra_reg_cml_2;
reg [ 4 : 0 ] rf_addra_reg_cml_1;
reg [ 4 : 0 ] rf_addrb_reg_cml_3;
reg [ 4 : 0 ] rf_addrb_reg_cml_2;
reg [ 4 : 0 ] rf_addrb_reg_cml_1;
 
 
 
parameter dw = `OR1200_OPERAND_WIDTH;
parameter aw = `OR1200_REGFILE_ADDR_WIDTH;
 
//
// I/O
//
 
//
// Clock and reset
//
input				clk;
input				rst;
 
//
// Write i/f
//
input				supv;
input				wb_freeze;
input	[aw-1:0]		addrw;
input	[dw-1:0]		dataw;
input				we;
input				flushpipe;
 
//
// Read i/f
//
input				id_freeze;
input	[aw-1:0]		addra;
input	[aw-1:0]		addrb;
output	[dw-1:0]		dataa;
output	[dw-1:0]		datab;
input				rda;
input				rdb;
 
//
// SPR access for debugging purposes
//
input				spr_cs;
input				spr_write;
input	[31:0]			spr_addr;
input	[31:0]			spr_dat_i;
output	[31:0]			spr_dat_o;
 
//
// Internal wires and regs
//
wire	[dw-1:0]		from_rfa;
wire	[dw-1:0]		from_rfb;
reg	[dw:0]			dataa_saved;
reg	[dw:0]			datab_saved;
wire	[aw-1:0]		rf_addra;
wire	[aw-1:0]		rf_addrw;
wire	[dw-1:0]		rf_dataw;
wire				rf_we;
wire				spr_valid;
wire				rf_ena;
wire				rf_enb;
reg				rf_we_allow;
 
//
// SPR access is valid when spr_cs is asserted and
// SPR address matches GPR addresses
//
 
// SynEDA CoreMultiplier
// assignment(s): spr_valid
// replace(s): spr_addr
assign spr_valid = spr_cs & (spr_addr_cml_2[10:5] == `OR1200_SPR_RF);
 
//
// SPR data output is always from RF A
//
assign spr_dat_o = from_rfa;
 
//
// Operand A comes from RF or from saved A register
//
 
// SynEDA CoreMultiplier
// assignment(s): dataa
// replace(s): from_rfa, dataa_saved
assign dataa = (dataa_saved_cml_3[32]) ? dataa_saved_cml_3[31:0] : from_rfa_cml_3;
 
//
// Operand B comes from RF or from saved B register
//
 
// SynEDA CoreMultiplier
// assignment(s): datab
// replace(s): datab_saved
assign datab = (datab_saved_cml_3[32]) ? datab_saved_cml_3[31:0] : from_rfb;
 
//
// RF A read address is either from SPRS or normal from CPU control
//
 
// SynEDA CoreMultiplier
// assignment(s): rf_addra
// replace(s): spr_write, spr_addr, spr_valid
assign rf_addra = (spr_valid_cml_3 & !spr_write_cml_3) ? spr_addr_cml_3[4:0] : addra;
 
//
// RF write address is either from SPRS or normal from CPU control
//
 
// SynEDA CoreMultiplier
// assignment(s): rf_addrw
// replace(s): addrw, spr_write, spr_addr
assign rf_addrw = (spr_valid & spr_write_cml_2) ? spr_addr_cml_2[4:0] : addrw_cml_2;
 
//
// RF write data is either from SPRS or normal from CPU datapath
//
 
// SynEDA CoreMultiplier
// assignment(s): rf_dataw
// replace(s): dataw, spr_write, spr_dat_i, spr_valid
assign rf_dataw = (spr_valid_cml_3 & spr_write_cml_3) ? spr_dat_i_cml_3 : dataw_cml_3;
 
//
// RF write enable is either from SPRS or normal from CPU control
//
 
// SynEDA CoreMultiplier
// assignment(s): rf_we_allow
// replace(s): wb_freeze, rf_we_allow
always @(posedge rst or posedge clk)
	if (rst)
		rf_we_allow <= #1 1'b1;
	else begin  rf_we_allow <= rf_we_allow_cml_3; if (~wb_freeze_cml_3)
		rf_we_allow <= #1 ~flushpipe; end
 
 
// SynEDA CoreMultiplier
// assignment(s): rf_we
// replace(s): wb_freeze, spr_write, rf_addrw, spr_valid, rf_we_allow
assign rf_we = ((spr_valid_cml_3 & spr_write_cml_3) | (we & ~wb_freeze_cml_3)) & rf_we_allow_cml_3 & (supv | (|rf_addrw_cml_3));
 
//
// CS RF A asserted when instruction reads operand A and ID stage
// is not stalled
//
 
// SynEDA CoreMultiplier
// assignment(s): rf_ena
// replace(s): spr_valid
assign rf_ena = rda & ~id_freeze | spr_valid_cml_3;	// probably works with fixed binutils
// assign rf_ena = 1'b1;			// does not work with single-stepping
//assign rf_ena = ~id_freeze | spr_valid;	// works with broken binutils 
 
//
// CS RF B asserted when instruction reads operand B and ID stage
// is not stalled
//
 
// SynEDA CoreMultiplier
// assignment(s): rf_enb
// replace(s): spr_valid
assign rf_enb = rdb & ~id_freeze | spr_valid_cml_3;
// assign rf_enb = 1'b1;
//assign rf_enb = ~id_freeze | spr_valid;	// works with broken binutils 
 
//
// Stores operand from RF_A into temp reg when pipeline is frozen
//
 
// SynEDA CoreMultiplier
// assignment(s): dataa_saved
// replace(s): from_rfa, dataa_saved
always @(posedge clk or posedge rst)
	if (rst) begin
		dataa_saved <= #1 33'b0;
	end
	else begin  dataa_saved <= dataa_saved_cml_3; if (id_freeze & !dataa_saved_cml_3[32]) begin
		dataa_saved <= #1 {1'b1, from_rfa_cml_3};
	end
	else if (!id_freeze)
		dataa_saved <= #1 33'b0; end
 
//
// Stores operand from RF_B into temp reg when pipeline is frozen
//
 
// SynEDA CoreMultiplier
// assignment(s): datab_saved
// replace(s): datab_saved
always @(posedge clk or posedge rst)
	if (rst) begin
		datab_saved <= #1 33'b0;
	end
	else begin  datab_saved <= datab_saved_cml_3; if (id_freeze & !datab_saved_cml_3[32]) begin
		datab_saved <= #1 {1'b1, from_rfb};
	end
	else if (!id_freeze)
		datab_saved <= #1 33'b0; end
 
`ifdef OR1200_RFRAM_TWOPORT
 
//
// Instantiation of register file two-port RAM A
//
or1200_tpram_32x32 rf_a(
	// Port A
	.clk_a(clk),
	.rst_a(rst),
	.ce_a(rf_ena),
	.we_a(1'b0),
	.oe_a(1'b1),
	.addr_a(rf_addra),
	.di_a(32'h0000_0000),
	.do_a(from_rfa),
 
	// Port B
	.clk_b(clk),
	.rst_b(rst),
	.ce_b(rf_we),
	.we_b(rf_we),
	.oe_b(1'b0),
	.addr_b(rf_addrw),
	.di_b(rf_dataw),
	.do_b()
);
 
//
// Instantiation of register file two-port RAM B
//
or1200_tpram_32x32 rf_b(
	// Port A
	.clk_a(clk),
	.rst_a(rst),
	.ce_a(rf_enb),
	.we_a(1'b0),
	.oe_a(1'b1),
	.addr_a(addrb),
	.di_a(32'h0000_0000),
	.do_a(from_rfb),
 
	// Port B
	.clk_b(clk),
	.rst_b(rst),
	.ce_b(rf_we),
	.we_b(rf_we),
	.oe_b(1'b0),
	.addr_b(rf_addrw),
	.di_b(rf_dataw),
	.do_b()
);
 
`else
 
`ifdef OR1200_RFRAM_DUALPORT
 
//
// Instantiation of register file two-port RAM A
//
or1200_dpram_32x32 rf_a(
	// Port A
	.clk_a(clk),
	.rst_a(rst),
	.ce_a(rf_ena),
	.oe_a(1'b1),
	.addr_a(rf_addra),
	.do_a(from_rfa),
 
	// Port B
	.clk_b(clk),
	.rst_b(rst),
	.ce_b(rf_we),
	.we_b(rf_we),
	.addr_b(rf_addrw),
	.di_b(rf_dataw)
);
 
//
// Instantiation of register file two-port RAM B
//
or1200_dpram_32x32 rf_b(
	// Port A
	.clk_a(clk),
	.rst_a(rst),
	.ce_a(rf_enb),
	.oe_a(1'b1),
	.addr_a(addrb),
	.do_a(from_rfb),
 
	// Port B
	.clk_b(clk),
	.rst_b(rst),
	.ce_b(rf_we),
	.we_b(rf_we),
	.addr_b(rf_addrw),
	.di_b(rf_dataw)
);
 
`else
 
`ifdef OR1200_RFRAM_GENERIC
 
//
// Instantiation of generic (flip-flop based) register file
//
or1200_rfram_generic rf_a(
	// Clock and reset
	.clk(clk),
	.rst(rst),
 
	// Port A
	.ce_a(rf_ena),
	.addr_a(rf_addra),
	.do_a(from_rfa),
 
	// Port B
	.ce_b(rf_enb),
	.addr_b(addrb),
	.do_b(from_rfb),
 
	// Port W
	.ce_w(rf_we),
	.we_w(rf_we),
	.addr_w(rf_addrw),
	.di_w(rf_dataw)
);
 
`else
 
 
`ifdef OR1200_RAM_MODELS_VIRTEX
 
//
//	Non-generic FPGA model instantiations
//
 
//	write port: no add-reg
//	read port: add-reg
 
//	write port
//	a -> rf_addrw
//	d -> rf_dataw
//	we -> rf_we
//	spo -> open
 
//	read port
//	dpra -> rf_addra_reg registered
//	dpo -> from_rfa_int
 
wire	[dw-1:0]		from_rfa_int;
wire	[dw-1:0]		from_rfb_int;
 
reg	[4:0]	rf_addra_reg;		// RAM address a registered
reg	[4:0]	rf_addrb_reg;		// RAM address b registered
 
 
// SynEDA CoreMultiplier
// assignment(s): rf_addra_reg
// replace(s): rf_addra_reg
always @(posedge clk or posedge rst)
	if (rst)
		rf_addra_reg <= #1 {32{1'b0}};
	else begin  rf_addra_reg <= rf_addra_reg_cml_3; if (rf_ena)
		rf_addra_reg <= #1 rf_addra; end
 
 
 
// SynEDA CoreMultiplier
// assignment(s): rf_addrb_reg
// replace(s): rf_addrb_reg
always @(posedge clk or posedge rst)
	if (rst)
		rf_addrb_reg <= #1 {32{1'b0}};
	else begin  rf_addrb_reg <= rf_addrb_reg_cml_3; if (rf_enb)
		rf_addrb_reg <= #1 addrb; end
 
rf_sub_cm4_22 rf_sub_ia(
		.clk_i_cml_3(clk_i_cml_3),
		.cmls(cmls),
	.a(rf_addrw),
	.d(rf_dataw),
	.dpra(rf_addra_reg),
	.clk(clk),
	.we(rf_we),
	.spo(),
	.dpo(from_rfa_int));
 
rf_sub_cm4_24 rf_sub_ib(
		.clk_i_cml_3(clk_i_cml_3),
		.cmls(cmls),
	.a(rf_addrw),
	.d(rf_dataw),
	.dpra(rf_addrb_reg),
	.clk(clk),
	.we(rf_we),
	.spo(),
	.dpo(from_rfb_int));
 
 
// SynEDA CoreMultiplier
// assignment(s): from_rfa
// replace(s): from_rfa_int, rf_addra_reg
assign from_rfa = (rf_addra_reg_cml_1 == 5'h00) ? 32'h00000000 : from_rfa_int_cml_1;
 
// SynEDA CoreMultiplier
// assignment(s): from_rfb
// replace(s): from_rfb_int, rf_addrb_reg
assign from_rfb = (rf_addrb_reg_cml_3 == 5'h00) ? 32'h00000000 : from_rfb_int_cml_3;
 
`else
 
//
// RFRAM type not specified
//
initial begin
	$display("Define RFRAM type.");
	$finish;
end
 
`endif
`endif
`endif
`endif
 
 
always @ (posedge clk_i_cml_1) begin
addrw_cml_1 <= addrw;
spr_write_cml_1 <= spr_write;
spr_addr_cml_1 <= spr_addr;
spr_dat_i_cml_1 <= spr_dat_i;
dataa_saved_cml_1 <= dataa_saved;
datab_saved_cml_1 <= datab_saved;
rf_we_allow_cml_1 <= rf_we_allow;
from_rfa_int_cml_1 <= from_rfa_int;
from_rfb_int_cml_1 <= from_rfb_int;
rf_addra_reg_cml_1 <= rf_addra_reg;
rf_addrb_reg_cml_1 <= rf_addrb_reg;
end
always @ (posedge clk_i_cml_2) begin
addrw_cml_2 <= addrw_cml_1;
spr_write_cml_2 <= spr_write_cml_1;
spr_addr_cml_2 <= spr_addr_cml_1;
spr_dat_i_cml_2 <= spr_dat_i_cml_1;
from_rfa_cml_2 <= from_rfa;
dataa_saved_cml_2 <= dataa_saved_cml_1;
datab_saved_cml_2 <= datab_saved_cml_1;
rf_we_allow_cml_2 <= rf_we_allow_cml_1;
from_rfb_int_cml_2 <= from_rfb_int_cml_1;
rf_addra_reg_cml_2 <= rf_addra_reg_cml_1;
rf_addrb_reg_cml_2 <= rf_addrb_reg_cml_1;
end
always @ (posedge clk_i_cml_3) begin
wb_freeze_cml_3 <= wb_freeze;
dataw_cml_3 <= dataw;
spr_write_cml_3 <= spr_write_cml_2;
spr_addr_cml_3 <= spr_addr_cml_2;
spr_dat_i_cml_3 <= spr_dat_i_cml_2;
from_rfa_cml_3 <= from_rfa_cml_2;
dataa_saved_cml_3 <= dataa_saved_cml_2;
datab_saved_cml_3 <= datab_saved_cml_2;
rf_addrw_cml_3 <= rf_addrw;
spr_valid_cml_3 <= spr_valid;
rf_we_allow_cml_3 <= rf_we_allow_cml_2;
from_rfb_int_cml_3 <= from_rfb_int_cml_2;
rf_addra_reg_cml_3 <= rf_addra_reg_cml_2;
rf_addrb_reg_cml_3 <= rf_addrb_reg_cml_2;
end
endmodule