mor1kx-bemicrocv/ip/altera/ddr3/altera_merlin_master_translator.sv

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2016-08-04 19:22:38 +02:00
// (C) 2001-2015 Altera Corporation. All rights reserved.
// Your use of Altera Corporation's design tools, logic functions and other
// software and tools, and its AMPP partner logic functions, and any output
// files any of the foregoing (including device programming or simulation
// files), and any associated documentation or information are expressly subject
// to the terms and conditions of the Altera Program License Subscription
// Agreement, Altera MegaCore Function License Agreement, or other applicable
// license agreement, including, without limitation, that your use is for the
// sole purpose of programming logic devices manufactured by Altera and sold by
// Altera or its authorized distributors. Please refer to the applicable
// agreement for further details.
// $Id: //acds/rel/15.1/ip/merlin/altera_merlin_master_translator/altera_merlin_master_translator.sv#1 $
// $Revision: #1 $
// $Date: 2015/08/09 $
// $Author: swbranch $
// --------------------------------------
// Merlin Master Translator
//
// Converts an Avalon-MM master interface into an
// Avalon-MM "universal" master interface.
//
// The universal interface is defined as the superset of ports
// and parameters that can represent any legal Avalon
// interface.
// --------------------------------------
`timescale 1 ns / 1 ns
module altera_merlin_master_translator #(
parameter
// widths
AV_ADDRESS_W = 32,
AV_DATA_W = 32,
AV_BURSTCOUNT_W = 4,
AV_BYTEENABLE_W = 4,
UAV_ADDRESS_W = 38,
UAV_BURSTCOUNT_W = 10,
// optional ports
USE_BURSTCOUNT = 1,
USE_BEGINBURSTTRANSFER = 0,
USE_BEGINTRANSFER = 0,
USE_CHIPSELECT = 0,
USE_READ = 1,
USE_READDATAVALID = 1,
USE_WRITE = 1,
USE_WAITREQUEST = 1,
USE_WRITERESPONSE = 0,
USE_READRESPONSE = 0,
AV_REGISTERINCOMINGSIGNALS = 0,
AV_SYMBOLS_PER_WORD = 4,
AV_ADDRESS_SYMBOLS = 0,
// must be enabled for a bursting master
AV_CONSTANT_BURST_BEHAVIOR = 1,
UAV_CONSTANT_BURST_BEHAVIOR = 0,
AV_BURSTCOUNT_SYMBOLS = 0,
AV_LINEWRAPBURSTS = 0
)(
input wire clk,
input wire reset,
// Universal Avalon Master
output reg uav_write,
output reg uav_read,
output reg [UAV_ADDRESS_W -1 : 0] uav_address,
output reg [UAV_BURSTCOUNT_W -1 : 0] uav_burstcount,
output wire [AV_BYTEENABLE_W -1 : 0] uav_byteenable,
output wire [AV_DATA_W -1 : 0] uav_writedata,
output wire uav_lock,
output wire uav_debugaccess,
output wire uav_clken,
input wire [AV_DATA_W -1 : 0] uav_readdata,
input wire uav_readdatavalid,
input wire uav_waitrequest,
input wire [1 : 0] uav_response,
input wire uav_writeresponsevalid,
// Avalon-MM Anti-master (slave)
input reg av_write,
input reg av_read,
input wire [AV_ADDRESS_W -1 : 0] av_address,
input wire [AV_BYTEENABLE_W -1 : 0] av_byteenable,
input wire [AV_BURSTCOUNT_W -1 : 0] av_burstcount,
input wire [AV_DATA_W -1 : 0] av_writedata,
input wire av_begintransfer,
input wire av_beginbursttransfer,
input wire av_lock,
input wire av_chipselect,
input wire av_debugaccess,
input wire av_clken,
output wire [AV_DATA_W -1 : 0] av_readdata,
output wire av_readdatavalid,
output reg av_waitrequest,
output reg [1 : 0] av_response,
output reg av_writeresponsevalid
);
localparam BITS_PER_WORD = clog2(AV_SYMBOLS_PER_WORD);
localparam AV_MAX_SYMBOL_BURST = flog2(pow2(AV_BURSTCOUNT_W - 1) * (AV_BURSTCOUNT_SYMBOLS ? 1 : AV_SYMBOLS_PER_WORD));
localparam AV_MAX_SYMBOL_BURST_MINUS_ONE = AV_MAX_SYMBOL_BURST ? AV_MAX_SYMBOL_BURST - 1 : 0;
localparam UAV_BURSTCOUNT_H_OR_31 = (UAV_BURSTCOUNT_W > 32) ? 31 : UAV_BURSTCOUNT_W - 1;
localparam UAV_ADDRESS_H_OR_31 = (UAV_ADDRESS_W > 32) ? 31 : UAV_ADDRESS_W - 1;
localparam BITS_PER_WORD_BURSTCOUNT = (UAV_BURSTCOUNT_W == 1) ? 0 : BITS_PER_WORD;
localparam BITS_PER_WORD_ADDRESS = (UAV_ADDRESS_W == 1) ? 0 : BITS_PER_WORD;
localparam ADDRESS_LOW = AV_ADDRESS_SYMBOLS ? 0 : BITS_PER_WORD_ADDRESS;
localparam BURSTCOUNT_LOW = AV_BURSTCOUNT_SYMBOLS ? 0 : BITS_PER_WORD_BURSTCOUNT;
localparam ADDRESS_HIGH = (UAV_ADDRESS_W > AV_ADDRESS_W + ADDRESS_LOW) ? AV_ADDRESS_W : (UAV_ADDRESS_W - ADDRESS_LOW);
localparam BURSTCOUNT_HIGH = (UAV_BURSTCOUNT_W > AV_BURSTCOUNT_W + BURSTCOUNT_LOW) ? AV_BURSTCOUNT_W : (UAV_BURSTCOUNT_W - BURSTCOUNT_LOW);
function integer flog2;
input [31:0] depth;
integer i;
begin
i = depth;
if ( i <= 0 ) flog2 = 0;
else begin
for (flog2 = -1; i > 0; flog2 = flog2 + 1)
i = i >> 1;
end
end
endfunction // flog2
// ------------------------------------------------------------
// Calculates the ceil(log2()) of the input val.
//
// Limited to a positive 32-bit input value.
// ------------------------------------------------------------
function integer clog2;
input[31:0] val;
reg[31:0] i;
begin
i = 1;
clog2 = 0;
while (i < val) begin
clog2 = clog2 + 1;
i = i[30:0] << 1;
end
end
endfunction
function integer pow2;
input [31:0] toShift;
begin
pow2 = 1;
pow2 = pow2 << toShift;
end
endfunction // pow2
// -------------------------------------------------
// Assign some constants to appropriately-sized signals to
// avoid synthesis warnings. This also helps some simulators
// with their inferred sensitivity lists.
//
// The symbols per word calculation here rounds non-power of two
// symbols to the next highest power of two, which is what we want
// when calculating the decrementing byte count.
// -------------------------------------------------
wire [31 : 0] symbols_per_word_int = 2**(clog2(AV_SYMBOLS_PER_WORD[UAV_BURSTCOUNT_H_OR_31 : 0]));
wire [UAV_BURSTCOUNT_H_OR_31 : 0] symbols_per_word = symbols_per_word_int[UAV_BURSTCOUNT_H_OR_31 : 0];
reg internal_beginbursttransfer;
reg internal_begintransfer;
reg [UAV_ADDRESS_W -1 : 0] uav_address_pre;
reg [UAV_BURSTCOUNT_W -1 : 0] uav_burstcount_pre;
reg uav_read_pre;
reg uav_write_pre;
reg read_accepted;
// -------------------------------------------------
// Pass through signals that we don't touch
// -------------------------------------------------
assign uav_writedata = av_writedata;
assign uav_byteenable = av_byteenable;
assign uav_lock = av_lock;
assign uav_debugaccess = av_debugaccess;
assign uav_clken = av_clken;
assign av_readdata = uav_readdata;
assign av_readdatavalid = uav_readdatavalid;
// -------------------------------------------------
// Response signals
// -------------------------------------------------
always_comb begin
if (!USE_READRESPONSE && !USE_WRITERESPONSE)
av_response = '0;
else
av_response = uav_response;
if (USE_WRITERESPONSE) begin
av_writeresponsevalid = uav_writeresponsevalid;
end else begin
av_writeresponsevalid = '0;
end
end
// -------------------------------------------------
// Convert byte and word addresses into byte addresses
// -------------------------------------------------
always_comb begin
uav_address_pre = {UAV_ADDRESS_W{1'b0}};
if (AV_ADDRESS_SYMBOLS)
uav_address_pre[(ADDRESS_HIGH ? ADDRESS_HIGH - 1 : 0) : 0] = av_address[(ADDRESS_HIGH ? ADDRESS_HIGH - 1 : 0) : 0];
else begin
uav_address_pre[ADDRESS_LOW + ADDRESS_HIGH - 1 : ADDRESS_LOW] = av_address[(ADDRESS_HIGH ? ADDRESS_HIGH - 1 : 0) : 0];
end
end
// -------------------------------------------------
// Convert burstcount into symbol units
// -------------------------------------------------
always_comb begin
uav_burstcount_pre = symbols_per_word; // default to a single transfer
if (USE_BURSTCOUNT) begin
uav_burstcount_pre = {UAV_BURSTCOUNT_W{1'b0}};
if (AV_BURSTCOUNT_SYMBOLS)
uav_burstcount_pre[(BURSTCOUNT_HIGH ? BURSTCOUNT_HIGH - 1 : 0) :0] = av_burstcount[(BURSTCOUNT_HIGH ? BURSTCOUNT_HIGH - 1 : 0) : 0];
else begin
uav_burstcount_pre[UAV_BURSTCOUNT_W - 1 : BURSTCOUNT_LOW] = av_burstcount[(BURSTCOUNT_HIGH ? BURSTCOUNT_HIGH - 1 : 0) : 0];
end
end
end
// -------------------------------------------------
// This is where we perform the per-transfer address and burstcount
// calculations that are required by downstream modules.
// -------------------------------------------------
reg [UAV_ADDRESS_W -1 : 0] address_register;
wire [UAV_BURSTCOUNT_W -1 : 0] burstcount_register;
reg [UAV_BURSTCOUNT_W : 0] burstcount_register_lint;
assign burstcount_register = burstcount_register_lint[UAV_BURSTCOUNT_W -1 : 0];
always_comb begin
uav_address = uav_address_pre;
uav_burstcount = uav_burstcount_pre;
if (AV_CONSTANT_BURST_BEHAVIOR && !UAV_CONSTANT_BURST_BEHAVIOR && ~internal_beginbursttransfer) begin
uav_address = address_register;
uav_burstcount = burstcount_register;
end
end
reg first_burst_stalled;
reg burst_stalled;
wire [UAV_ADDRESS_W -1 : 0] combi_burst_addr_reg;
wire [UAV_ADDRESS_W -1 : 0] combi_addr_reg;
generate
if (AV_LINEWRAPBURSTS && AV_MAX_SYMBOL_BURST != 0) begin
if (AV_MAX_SYMBOL_BURST > UAV_ADDRESS_W - 1) begin
assign combi_burst_addr_reg = { uav_address_pre[UAV_ADDRESS_W-1:0] + AV_SYMBOLS_PER_WORD[UAV_ADDRESS_W-1:0] };
assign combi_addr_reg = { address_register[UAV_ADDRESS_W-1:0] + AV_SYMBOLS_PER_WORD[UAV_ADDRESS_W-1:0] };
end
else begin
assign combi_burst_addr_reg = { uav_address_pre[UAV_ADDRESS_W - 1 : AV_MAX_SYMBOL_BURST], uav_address_pre[AV_MAX_SYMBOL_BURST_MINUS_ONE:0] + AV_SYMBOLS_PER_WORD[AV_MAX_SYMBOL_BURST_MINUS_ONE:0] };
assign combi_addr_reg = { address_register[UAV_ADDRESS_W - 1 : AV_MAX_SYMBOL_BURST], address_register[AV_MAX_SYMBOL_BURST_MINUS_ONE:0] + AV_SYMBOLS_PER_WORD[AV_MAX_SYMBOL_BURST_MINUS_ONE:0] };
end
end
else begin
assign combi_burst_addr_reg = uav_address_pre + AV_SYMBOLS_PER_WORD[UAV_ADDRESS_H_OR_31:0];
assign combi_addr_reg = address_register + AV_SYMBOLS_PER_WORD[UAV_ADDRESS_H_OR_31:0];
end
endgenerate
always @(posedge clk, posedge reset) begin
if (reset) begin
address_register <= '0;
burstcount_register_lint <= '0;
end else begin
address_register <= address_register;
burstcount_register_lint <= burstcount_register_lint;
if (internal_beginbursttransfer || first_burst_stalled) begin
if (av_waitrequest) begin
address_register <= uav_address_pre;
burstcount_register_lint[UAV_BURSTCOUNT_W - 1 : 0] <= uav_burstcount_pre;
end else begin
address_register <= combi_burst_addr_reg;
burstcount_register_lint <= uav_burstcount_pre - symbols_per_word;
end
end else if (internal_begintransfer || burst_stalled) begin
if (~av_waitrequest) begin
address_register <= combi_addr_reg;
burstcount_register_lint <= burstcount_register - symbols_per_word;
end
end
end
end
always @(posedge clk, posedge reset) begin
if (reset) begin
first_burst_stalled <= 1'b0;
burst_stalled <= 1'b0;
end else begin
if (internal_beginbursttransfer || first_burst_stalled) begin
if (av_waitrequest) begin
first_burst_stalled <= 1'b1;
end else begin
first_burst_stalled <= 1'b0;
end
end else if (internal_begintransfer || burst_stalled) begin
if (~av_waitrequest) begin
burst_stalled <= 1'b0;
end else begin
burst_stalled <= 1'b1;
end
end
end
end
// -------------------------------------------------
// Waitrequest translation
// -------------------------------------------------
always @(posedge clk, posedge reset) begin
if (reset)
read_accepted <= 1'b0;
else begin
read_accepted <= read_accepted;
if (read_accepted == 0)
read_accepted <= av_waitrequest ? uav_read_pre & ~uav_waitrequest : 1'b0;
else if (read_accepted == 1 && uav_readdatavalid == 1) // reset acceptance only when rdv arrives
read_accepted <= 1'b0;
end
end
reg write_accepted = 0;
generate if (AV_REGISTERINCOMINGSIGNALS) begin
always @(posedge clk, posedge reset) begin
if (reset)
write_accepted <= 1'b0;
else begin
write_accepted <=
~av_waitrequest ? 1'b0 :
uav_write & ~uav_waitrequest? 1'b1 :
write_accepted;
end
end
end endgenerate
always_comb begin
av_waitrequest = uav_waitrequest;
if (USE_READDATAVALID == 0) begin
av_waitrequest = uav_read_pre ? ~uav_readdatavalid : uav_waitrequest;
end
if (AV_REGISTERINCOMINGSIGNALS) begin
av_waitrequest =
uav_read_pre ? ~uav_readdatavalid :
uav_write_pre ? (internal_begintransfer | uav_waitrequest) & ~write_accepted :
1'b1;
end
if (USE_WAITREQUEST == 0) begin
av_waitrequest = 0;
end
end
// -------------------------------------------------
// Determine the output read and write signals from
// the read/write/chipselect input signals.
// -------------------------------------------------
always_comb begin
uav_write = 1'b0;
uav_write_pre = 1'b0;
uav_read = 1'b0;
uav_read_pre = 1'b0;
if (!USE_CHIPSELECT) begin
if (USE_READ) begin
uav_read_pre = av_read;
end
if (USE_WRITE) begin
uav_write_pre = av_write;
end
end else begin
if (!USE_WRITE && USE_READ) begin
uav_write_pre = av_chipselect & ~av_read;
uav_read_pre = av_read;
end else if (!USE_READ && USE_WRITE) begin
uav_write_pre = av_write;
uav_read_pre = av_chipselect & ~av_write;
end else if (USE_READ && USE_WRITE) begin
uav_write_pre = av_write;
uav_read_pre = av_read;
end
end
if (USE_READDATAVALID == 0)
uav_read = uav_read_pre & ~read_accepted;
else
uav_read = uav_read_pre;
if (AV_REGISTERINCOMINGSIGNALS == 0)
uav_write = uav_write_pre;
else
uav_write = uav_write_pre & ~write_accepted;
end
// -------------------------------------------------
// Begintransfer assignment
// -------------------------------------------------
reg end_begintransfer;
always_comb begin
if (USE_BEGINTRANSFER) begin
internal_begintransfer = av_begintransfer;
end else begin
internal_begintransfer = ( uav_write | uav_read ) & ~end_begintransfer;
end
end
always @(posedge clk or posedge reset) begin
if (reset) begin
end_begintransfer <= 1'b0;
end else begin
if (internal_begintransfer == 1 && uav_waitrequest)
end_begintransfer <= 1'b1;
else if (uav_waitrequest)
end_begintransfer <= end_begintransfer;
else
end_begintransfer <= 1'b0;
end
end
// -------------------------------------------------
// Beginbursttransfer assignment
// -------------------------------------------------
reg end_beginbursttransfer;
wire last_burst_transfer_pre;
wire last_burst_transfer_reg;
wire last_burst_transfer;
// compare values before the mux to shorten critical path; benchmark before changing
assign last_burst_transfer_pre = (uav_burstcount_pre == symbols_per_word);
assign last_burst_transfer_reg = (burstcount_register == symbols_per_word);
assign last_burst_transfer = (internal_beginbursttransfer) ? last_burst_transfer_pre : last_burst_transfer_reg;
always_comb begin
if (USE_BEGINBURSTTRANSFER) begin
internal_beginbursttransfer = av_beginbursttransfer;
end else begin
internal_beginbursttransfer = uav_read ? internal_begintransfer : internal_begintransfer && ~end_beginbursttransfer;
end
end
always @(posedge clk or posedge reset) begin
if (reset) begin
end_beginbursttransfer <= 1'b0;
end else begin
end_beginbursttransfer <= end_beginbursttransfer;
if (last_burst_transfer && internal_begintransfer || uav_read) begin
end_beginbursttransfer <= 1'b0;
end
else if (uav_write && internal_begintransfer) begin
end_beginbursttransfer <= 1'b1;
end
end
end
// synthesis translate_off
// ------------------------------------------------
// check_1 : for waitrequest signal violation
// Ensure that when waitreqeust is asserted, the master is not allowed to change its controls
// Exception : begintransfer / beginbursttransfer
// : previously not in any transaction (idle)
// Note : Not checking clken which is not exactly part of Avalon controls/inputs
// : Not using system verilog assertions (seq/prop) since it is not supported if using Modelsim_SE
// ------------------------------------------------
reg av_waitrequest_r;
reg av_write_r, av_read_r, av_lock_r, av_chipselect_r, av_debugaccess_r;
reg [AV_ADDRESS_W-1:0] av_address_r;
reg [AV_BYTEENABLE_W-1:0] av_byteenable_r;
reg [AV_BURSTCOUNT_W-1:0] av_burstcount_r;
reg [AV_DATA_W-1:0] av_writedata_r;
always @(posedge clk or posedge reset) begin
if (reset) begin
av_waitrequest_r <= '0;
av_write_r <= '0;
av_read_r <= '0;
av_lock_r <= '0;
av_chipselect_r <= '0;
av_debugaccess_r <= '0;
av_address_r <= '0;
av_byteenable_r <= '0;
av_burstcount_r <= '0;
av_writedata_r <= '0;
end else begin
av_waitrequest_r <= av_waitrequest;
av_write_r <= av_write;
av_read_r <= av_read;
av_lock_r <= av_lock;
av_chipselect_r <= av_chipselect;
av_debugaccess_r <= av_debugaccess;
av_address_r <= av_address;
av_byteenable_r <= av_byteenable;
av_burstcount_r <= av_burstcount;
av_writedata_r <= av_writedata;
if (
av_waitrequest_r && // When waitrequest is asserted
(
(av_write != av_write_r) || // Checks that : Input controls/data does not change
(av_read != av_read_r) ||
(av_lock != av_lock_r) ||
(av_debugaccess != av_debugaccess_r) ||
(av_address != av_address_r) ||
(av_byteenable != av_byteenable_r) ||
(av_burstcount != av_burstcount_r)
) &&
(av_write_r | av_read_r) && // Check only when : previously initiated a write/read
(!USE_CHIPSELECT | av_chipselect_r) // and chipselect was asserted (or unused)
) begin
$display( "%t: %m: Error: Input controls/data changed while av_waitrequest is asserted.", $time());
$display("av_address %x --> %x", av_address_r , av_address );
$display("av_byteenable %x --> %x", av_byteenable_r , av_byteenable );
$display("av_burstcount %x --> %x", av_burstcount_r , av_burstcount );
$display("av_writedata %x --> %x", av_writedata_r , av_writedata );
$display("av_write %x --> %x", av_write_r , av_write );
$display("av_read %x --> %x", av_read_r , av_read );
$display("av_lock %x --> %x", av_lock_r , av_lock );
$display("av_chipselect %x --> %x", av_chipselect_r , av_chipselect );
$display("av_debugaccess %x --> %x", av_debugaccess_r , av_debugaccess );
end
end
// end check_1
end
// synthesis translate_on
endmodule