623 lines
29 KiB
Systemverilog
623 lines
29 KiB
Systemverilog
// (C) 2001-2015 Altera Corporation. All rights reserved.
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// Your use of Altera Corporation's design tools, logic functions and other
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// software and tools, and its AMPP partner logic functions, and any output
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// files any of the foregoing (including device programming or simulation
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// files), and any associated documentation or information are expressly subject
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// to the terms and conditions of the Altera Program License Subscription
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// Agreement, Altera MegaCore Function License Agreement, or other applicable
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// license agreement, including, without limitation, that your use is for the
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// sole purpose of programming logic devices manufactured by Altera and sold by
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// Altera or its authorized distributors. Please refer to the applicable
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// agreement for further details.
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// (C) 2001-2011 Altera Corporation. All rights reserved.
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// Your use of Altera Corporation's design tools, logic functions and other
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// software and tools, and its AMPP partner logic functions, and any output
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// files any of the foregoing (including device programming or simulation
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// files), and any associated documentation or information are expressly subject
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// to the terms and conditions of the Altera Program License Subscription
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// Agreement, Altera MegaCore Function License Agreement, or other applicable
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// license agreement, including, without limitation, that your use is for the
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// sole purpose of programming logic devices manufactured by Altera and sold by
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// Altera or its authorized distributors. Please refer to the applicable
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// agreement for further details.
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// $Id: //acds/rel/15.1/ip/merlin/altera_merlin_slave_agent/altera_merlin_slave_agent.sv#1 $
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// $Revision: #1 $
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// $Date: 2015/08/09 $
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// $Author: swbranch $
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`timescale 1 ns / 1 ns
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module altera_merlin_slave_agent
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#(
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// Packet parameters
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parameter PKT_BEGIN_BURST = 81,
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parameter PKT_DATA_H = 31,
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parameter PKT_DATA_L = 0,
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parameter PKT_SYMBOL_W = 8,
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parameter PKT_BYTEEN_H = 71,
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parameter PKT_BYTEEN_L = 68,
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parameter PKT_ADDR_H = 63,
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parameter PKT_ADDR_L = 32,
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parameter PKT_TRANS_LOCK = 87,
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parameter PKT_TRANS_COMPRESSED_READ = 67,
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parameter PKT_TRANS_POSTED = 66,
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parameter PKT_TRANS_WRITE = 65,
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parameter PKT_TRANS_READ = 64,
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parameter PKT_SRC_ID_H = 74,
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parameter PKT_SRC_ID_L = 72,
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parameter PKT_DEST_ID_H = 77,
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parameter PKT_DEST_ID_L = 75,
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parameter PKT_BURSTWRAP_H = 85,
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parameter PKT_BURSTWRAP_L = 82,
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parameter PKT_BYTE_CNT_H = 81,
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parameter PKT_BYTE_CNT_L = 78,
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parameter PKT_PROTECTION_H = 86,
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parameter PKT_PROTECTION_L = 86,
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parameter PKT_RESPONSE_STATUS_H = 89,
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parameter PKT_RESPONSE_STATUS_L = 88,
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parameter PKT_BURST_SIZE_H = 92,
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parameter PKT_BURST_SIZE_L = 90,
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parameter PKT_ORI_BURST_SIZE_L = 93,
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parameter PKT_ORI_BURST_SIZE_H = 95,
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parameter ST_DATA_W = 96,
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parameter ST_CHANNEL_W = 32,
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// Slave parameters
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parameter ADDR_W = PKT_ADDR_H - PKT_ADDR_L + 1,
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parameter AVS_DATA_W = PKT_DATA_H - PKT_DATA_L + 1,
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parameter AVS_BURSTCOUNT_W = 4,
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parameter PKT_SYMBOLS = AVS_DATA_W / PKT_SYMBOL_W,
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// Slave agent parameters
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parameter PREVENT_FIFO_OVERFLOW = 0,
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parameter SUPPRESS_0_BYTEEN_CMD = 1,
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parameter USE_READRESPONSE = 0,
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parameter USE_WRITERESPONSE = 0,
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// Derived slave parameters
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parameter AVS_BE_W = PKT_BYTEEN_H - PKT_BYTEEN_L + 1,
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parameter BURST_SIZE_W = 3,
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// Derived FIFO width
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parameter FIFO_DATA_W = ST_DATA_W + 1,
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// ECC parameter
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parameter ECC_ENABLE = 0
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) (
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input clk,
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input reset,
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// Universal-Avalon anti-slave
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output [ADDR_W-1:0] m0_address,
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output [AVS_BURSTCOUNT_W-1:0] m0_burstcount,
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output [AVS_BE_W-1:0] m0_byteenable,
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output m0_read,
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input [AVS_DATA_W-1:0] m0_readdata,
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input m0_waitrequest,
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output m0_write,
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output [AVS_DATA_W-1:0] m0_writedata,
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input m0_readdatavalid,
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output m0_debugaccess,
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output m0_lock,
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input [1:0] m0_response,
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input m0_writeresponsevalid,
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// Avalon-ST FIFO interfaces.
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// Note: there's no need to include the "data" field here, at least for
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// reads, since readdata is filled in from slave info. To keep life
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// simple, have a data field, but fill it with 0s.
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// Av-st response fifo source interface
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output reg [FIFO_DATA_W-1:0] rf_source_data,
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output rf_source_valid,
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output rf_source_startofpacket,
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output rf_source_endofpacket,
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input rf_source_ready,
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// Av-st response fifo sink interface
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input [FIFO_DATA_W-1:0] rf_sink_data,
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input rf_sink_valid,
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input rf_sink_startofpacket,
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input rf_sink_endofpacket,
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output rf_sink_ready,
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// Av-st readdata fifo src interface, data and response
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// extra 2 bits for storing RESPONSE STATUS
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output [AVS_DATA_W+1:0] rdata_fifo_src_data,
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output rdata_fifo_src_valid,
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input rdata_fifo_src_ready,
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// Av-st readdata fifo sink interface
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input [AVS_DATA_W+1:0] rdata_fifo_sink_data,
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input rdata_fifo_sink_valid,
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output rdata_fifo_sink_ready,
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input rdata_fifo_sink_error,
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// Av-st sink command packet interface
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output cp_ready,
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input cp_valid,
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input [ST_DATA_W-1:0] cp_data,
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input [ST_CHANNEL_W-1:0] cp_channel,
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input cp_startofpacket,
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input cp_endofpacket,
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// Av-st source response packet interface
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input rp_ready,
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output reg rp_valid,
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output reg [ST_DATA_W-1:0] rp_data,
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output rp_startofpacket,
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output rp_endofpacket
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);
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// --------------------------------------------------
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// Ceil(log2()) function log2ceil of 4 = 2
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// --------------------------------------------------
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function integer log2ceil;
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input reg[63:0] val;
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reg [63:0] i;
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begin
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i = 1;
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log2ceil = 0;
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while (i < val) begin
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log2ceil = log2ceil + 1;
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i = i << 1;
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end
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end
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endfunction
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// ------------------------------------------------
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// Local Parameters
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// ------------------------------------------------
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localparam DATA_W = PKT_DATA_H - PKT_DATA_L + 1;
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localparam BE_W = PKT_BYTEEN_H - PKT_BYTEEN_L + 1;
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localparam MID_W = PKT_SRC_ID_H - PKT_SRC_ID_L + 1;
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localparam SID_W = PKT_DEST_ID_H - PKT_DEST_ID_L + 1;
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localparam BYTE_CNT_W = PKT_BYTE_CNT_H - PKT_BYTE_CNT_L + 1;
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localparam BURSTWRAP_W = PKT_BURSTWRAP_H - PKT_BURSTWRAP_L + 1;
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localparam BURSTSIZE_W = PKT_BURST_SIZE_H - PKT_BURST_SIZE_L + 1;
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localparam BITS_TO_MASK = log2ceil(PKT_SYMBOLS);
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localparam MAX_BURST = 1 << (AVS_BURSTCOUNT_W - 1);
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localparam BURSTING = (MAX_BURST > PKT_SYMBOLS);
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// ------------------------------------------------
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// Signals
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// ------------------------------------------------
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wire [DATA_W-1:0] cmd_data;
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wire [BE_W-1:0] cmd_byteen;
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wire [ADDR_W-1:0] cmd_addr;
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wire [MID_W-1:0] cmd_mid;
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wire [SID_W-1:0] cmd_sid;
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wire cmd_read;
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wire cmd_write;
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wire cmd_compressed;
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wire cmd_posted;
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wire [BYTE_CNT_W-1:0] cmd_byte_cnt;
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wire [BURSTWRAP_W-1:0] cmd_burstwrap;
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wire [BURSTSIZE_W-1:0] cmd_burstsize;
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wire cmd_debugaccess;
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wire suppress_cmd;
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wire byteen_asserted;
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wire suppress_read;
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wire suppress_write;
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wire needs_response_synthesis;
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wire generate_response;
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// Assign command fields
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assign cmd_data = cp_data[PKT_DATA_H :PKT_DATA_L ];
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assign cmd_byteen = cp_data[PKT_BYTEEN_H:PKT_BYTEEN_L];
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assign cmd_addr = cp_data[PKT_ADDR_H :PKT_ADDR_L ];
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assign cmd_compressed = cp_data[PKT_TRANS_COMPRESSED_READ];
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assign cmd_posted = cp_data[PKT_TRANS_POSTED];
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assign cmd_write = cp_data[PKT_TRANS_WRITE];
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assign cmd_read = cp_data[PKT_TRANS_READ];
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assign cmd_mid = cp_data[PKT_SRC_ID_H :PKT_SRC_ID_L];
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assign cmd_sid = cp_data[PKT_DEST_ID_H:PKT_DEST_ID_L];
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assign cmd_byte_cnt = cp_data[PKT_BYTE_CNT_H:PKT_BYTE_CNT_L];
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assign cmd_burstwrap = cp_data[PKT_BURSTWRAP_H:PKT_BURSTWRAP_L];
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assign cmd_burstsize = cp_data[PKT_BURST_SIZE_H:PKT_BURST_SIZE_L];
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assign cmd_debugaccess = cp_data[PKT_PROTECTION_L];
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// Local "ready_for_command" signal: deasserted when the agent is unable to accept
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// another command, e.g. rdv FIFO is full, (local readdata storage is full &&
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// ~rp_ready), ...
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// Say, this could depend on the type of command, for example, even if the
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// rdv FIFO is full, a write request can be accepted. For later.
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wire ready_for_command;
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wire local_lock = cp_valid & cp_data[PKT_TRANS_LOCK];
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wire local_write = cp_valid & cp_data[PKT_TRANS_WRITE];
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wire local_read = cp_valid & cp_data[PKT_TRANS_READ];
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wire local_compressed_read = cp_valid & cp_data[PKT_TRANS_COMPRESSED_READ];
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wire nonposted_write_endofpacket = ~cp_data[PKT_TRANS_POSTED] & local_write & cp_endofpacket;
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// num_symbols is PKT_SYMBOLS, appropriately sized.
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wire [31:0] int_num_symbols = PKT_SYMBOLS;
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wire [BYTE_CNT_W-1:0] num_symbols = int_num_symbols[BYTE_CNT_W-1:0];
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generate
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if (PREVENT_FIFO_OVERFLOW) begin : prevent_fifo_overflow_block
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// ---------------------------------------------------
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// Backpressure if the slave says to, or if FIFO overflow may occur.
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//
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// All commands are backpressured once the FIFO is full
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// even if they don't need storage. This breaks a long
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// combinatorial path from the master read/write through
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// this logic and back to the master via the backpressure
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// path.
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//
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// To avoid a loss of throughput the FIFO will be parameterized
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// one slot deeper. The extra slot should never be used in normal
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// operation, but should a slave misbehave and accept one more
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// read than it should then backpressure will kick in.
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//
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// An example: assume a slave with MPRT = 2. It can accept a
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// command sequence RRWW without backpressuring. If the FIFO is
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// only 2 deep, we'd backpressure the writes leading to loss of
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// throughput. If the FIFO is 3 deep, we'll only backpressure when
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// RRR... which is an illegal condition anyway.
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// ---------------------------------------------------
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assign ready_for_command = rf_source_ready;
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assign cp_ready = (~m0_waitrequest | suppress_cmd) && ready_for_command;
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end else begin : no_prevent_fifo_overflow_block
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// Do not suppress the command or the slave will
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// not be able to waitrequest
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assign ready_for_command = 1'b1;
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// Backpressure only if the slave says to.
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assign cp_ready = ~m0_waitrequest | suppress_cmd;
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end
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endgenerate
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generate if (SUPPRESS_0_BYTEEN_CMD && !BURSTING) begin : suppress_0_byteen_cmd_non_bursting
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assign byteen_asserted = |cmd_byteen;
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assign suppress_read = ~byteen_asserted;
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assign suppress_write = ~byteen_asserted;
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assign suppress_cmd = ~byteen_asserted;
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end else if (SUPPRESS_0_BYTEEN_CMD && BURSTING) begin: suppress_0_byteen_cmd_bursting
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assign byteen_asserted = |cmd_byteen;
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assign suppress_read = ~byteen_asserted;
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assign suppress_write = 1'b0;
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assign suppress_cmd = ~byteen_asserted && cmd_read;
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end else begin : no_suppress_0_byteen_cmd
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assign suppress_read = 1'b0;
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assign suppress_write = 1'b0;
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assign suppress_cmd = 1'b0;
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end
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endgenerate
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// -------------------------------------------------------------------
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// Extract avalon signals from command packet.
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// -------------------------------------------------------------------
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// Mask off the lower bits of address.
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// The burst adapter before this component will break narrow sized packets
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// into sub-bursts of length 1. However, the packet addresses are preserved,
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// which means this component may see size-aligned addresses.
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//
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// Masking ensures that the addresses seen by an Avalon slave are aligned to
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// the full data width instead of the size.
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//
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// Example:
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// output from burst adapter (datawidth=4, size=2 bytes):
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// subburst1 addr=0, subburst2 addr=2, subburst3 addr=4, subburst4 addr=6
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// expected output from slave agent:
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// subburst1 addr=0, subburst2 addr=0, subburst3 addr=4, subburst4 addr=4
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generate
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if (BITS_TO_MASK > 0) begin : mask_address
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assign m0_address = { cmd_addr[ADDR_W-1:BITS_TO_MASK], {BITS_TO_MASK{1'b0}} };
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end else begin : no_mask_address
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assign m0_address = cmd_addr;
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end
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endgenerate
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assign m0_byteenable = cmd_byteen;
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assign m0_writedata = cmd_data;
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// Note: no Avalon-MM slave in existence accepts uncompressed read bursts -
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// this sort of burst exists only in merlin fabric ST packets. What to do
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// if we see such a burst? All beats in that burst need to be transmitted
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// to the slave so we have enough space-time for byteenable expression.
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//
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// There can be multiple bursts in a packet, but only one beat per burst
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// in <most> cases. The exception is when we've decided not to insert a
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// burst adapter for efficiency reasons, in which case this agent is also
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// responsible for driving burstcount to 1 on each beat of an uncompressed
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// read burst.
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assign m0_read = ready_for_command & !suppress_read & (local_compressed_read | local_read);
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generate
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// AVS_BURSTCOUNT_W and BYTE_CNT_W may not be equal. Assign m0_burstcount
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// from a sub-range, or 0-pad, as appropriate.
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if (AVS_BURSTCOUNT_W > BYTE_CNT_W) begin : m0_burstcount_zero_pad
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wire [AVS_BURSTCOUNT_W - BYTE_CNT_W - 1 : 0] zero_pad = {(AVS_BURSTCOUNT_W - BYTE_CNT_W) {1'b0}};
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assign m0_burstcount = (local_read & ~local_compressed_read) ?
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{zero_pad, num_symbols} :
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{zero_pad, cmd_byte_cnt};
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end
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else begin : m0_burstcount_no_pad
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assign m0_burstcount = (local_read & ~local_compressed_read) ?
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num_symbols[AVS_BURSTCOUNT_W-1:0] :
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cmd_byte_cnt[AVS_BURSTCOUNT_W-1:0];
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end
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endgenerate
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assign m0_write = ready_for_command & local_write & !suppress_write;
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assign m0_lock = ready_for_command & local_lock & (m0_read | m0_write);
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assign m0_debugaccess = cmd_debugaccess;
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// -------------------------------------------------------------------
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// Indirection layer for response packet values. Some may always wire
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// directly from the slave translator; others will no doubt emerge from
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// various FIFOs.
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// What to put in resp_data when a write occured? Answer: it does not
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// matter, because only response status is needed for non-posted writes,
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// and the packet already has a field for that.
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//
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// We use the rdata_fifo to store write responses as well. This allows us
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// to handle backpressure on the response path, and allows write response
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// merging.
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assign rdata_fifo_src_valid = m0_readdatavalid | m0_writeresponsevalid;
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assign rdata_fifo_src_data = {m0_response, m0_readdata};
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// ------------------------------------------------------------------
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// Generate a token when read commands are suppressed. The token
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// is stored in the response FIFO, and will be used to synthesize
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// a read response. The same token is used for non-posted write
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// response synthesis.
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//
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// Note: this token is not generated for suppressed uncompressed read cycles;
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// the burst uncompression logic at the read side of the response FIFO
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// generates the correct number of responses.
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//
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// When the slave can return the response, let it do its job. Don't
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// synthesize a response in that case, unless we've suppressed the
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// the last transfer in a write sub-burst.
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// ------------------------------------------------------------------
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wire write_end_of_subburst;
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assign needs_response_synthesis = ((local_read | local_compressed_read) & suppress_read) ||
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(!USE_WRITERESPONSE && nonposted_write_endofpacket) ||
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(USE_WRITERESPONSE && write_end_of_subburst && suppress_write);
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// Avalon-ST interfaces to external response FIFO.
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//
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// For efficiency, when synthesizing a write response we only store a non-posted write
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// transaction at its endofpacket, even if it was split into multiple sub-bursts.
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//
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// When not synthesizing write responses, we store each sub-burst in the FIFO.
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// Each sub-burst to the slave will return a response, which corresponds to one
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// entry in the FIFO. We merge all the sub-burst responses on the final
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// sub-burst and send it on the response channel.
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wire internal_cp_endofburst;
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wire [31:0] minimum_bytecount_wire = PKT_SYMBOLS; // to solve qis warning
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wire [AVS_BURSTCOUNT_W-1:0] minimum_bytecount;
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assign minimum_bytecount = minimum_bytecount_wire[AVS_BURSTCOUNT_W-1:0];
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assign internal_cp_endofburst = (cmd_byte_cnt == minimum_bytecount);
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assign write_end_of_subburst = local_write & internal_cp_endofburst;
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assign rf_source_valid = (local_read | local_compressed_read | (nonposted_write_endofpacket && !USE_WRITERESPONSE) | (USE_WRITERESPONSE && internal_cp_endofburst && local_write))
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& ready_for_command & cp_ready;
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assign rf_source_startofpacket = cp_startofpacket;
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assign rf_source_endofpacket = cp_endofpacket;
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always @* begin
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// default: assign every command packet field to the response FIFO...
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rf_source_data = {1'b0, cp_data};
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// ... and override select fields as needed.
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rf_source_data[FIFO_DATA_W-1] = needs_response_synthesis;
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rf_source_data[PKT_DATA_H :PKT_DATA_L] = {DATA_W {1'b0}};
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rf_source_data[PKT_BYTEEN_H :PKT_BYTEEN_L] = cmd_byteen;
|
|
rf_source_data[PKT_ADDR_H :PKT_ADDR_L] = cmd_addr;
|
|
rf_source_data[PKT_TRANS_COMPRESSED_READ] = cmd_compressed;
|
|
rf_source_data[PKT_TRANS_POSTED] = cmd_posted;
|
|
rf_source_data[PKT_TRANS_WRITE] = cmd_write;
|
|
rf_source_data[PKT_TRANS_READ] = cmd_read;
|
|
rf_source_data[PKT_SRC_ID_H :PKT_SRC_ID_L] = cmd_mid;
|
|
rf_source_data[PKT_DEST_ID_H:PKT_DEST_ID_L] = cmd_sid;
|
|
rf_source_data[PKT_BYTE_CNT_H:PKT_BYTE_CNT_L] = cmd_byte_cnt;
|
|
rf_source_data[PKT_BURSTWRAP_H:PKT_BURSTWRAP_L] = cmd_burstwrap;
|
|
rf_source_data[PKT_BURST_SIZE_H:PKT_BURST_SIZE_L] = cmd_burstsize;
|
|
rf_source_data[PKT_PROTECTION_H:PKT_PROTECTION_L] = '0;
|
|
rf_source_data[PKT_PROTECTION_L] = cmd_debugaccess;
|
|
end
|
|
|
|
wire uncompressor_source_valid;
|
|
wire [BURSTSIZE_W-1:0] uncompressor_burstsize;
|
|
wire last_write_response;
|
|
|
|
// last_write_response indicates the last response of the broken-up write burst (sub-bursts).
|
|
// At this time, the final merged response is sent, and rp_valid is only asserted
|
|
// once for the whole burst.
|
|
generate
|
|
if (USE_WRITERESPONSE) begin
|
|
assign last_write_response = rf_sink_data[PKT_TRANS_WRITE] & rf_sink_endofpacket;
|
|
always @* begin
|
|
if (rf_sink_data[PKT_TRANS_WRITE] == 1)
|
|
rp_valid = (rdata_fifo_sink_valid | generate_response) & last_write_response & !rf_sink_data[PKT_TRANS_POSTED];
|
|
else
|
|
rp_valid = rdata_fifo_sink_valid | uncompressor_source_valid;
|
|
end
|
|
end else begin
|
|
assign last_write_response = 1'b0;
|
|
always @* begin
|
|
rp_valid = rdata_fifo_sink_valid | uncompressor_source_valid;
|
|
end
|
|
end
|
|
endgenerate
|
|
|
|
// ------------------------------------------------------------------
|
|
// Response merging
|
|
// ------------------------------------------------------------------
|
|
reg [1:0] current_response;
|
|
reg [1:0] response_merged;
|
|
generate
|
|
if (USE_WRITERESPONSE) begin : response_merging_all
|
|
reg first_write_response;
|
|
reg reset_merged_output;
|
|
reg [1:0] previous_response_in;
|
|
reg [1:0] previous_response;
|
|
|
|
always_ff @(posedge clk, posedge reset) begin
|
|
if (reset) begin
|
|
first_write_response <= 1'b1;
|
|
end
|
|
else begin // Merging work for write response, for read: previous_response_in = current_response
|
|
if (rf_sink_valid & (rdata_fifo_sink_valid | generate_response) & rf_sink_data[PKT_TRANS_WRITE]) begin
|
|
first_write_response <= 1'b0;
|
|
if (rf_sink_endofpacket)
|
|
first_write_response <= 1'b1;
|
|
end
|
|
end
|
|
end
|
|
|
|
always_comb begin
|
|
current_response = generate_response ? 2'b00 : rdata_fifo_sink_data[AVS_DATA_W+1:AVS_DATA_W] | {2{rdata_fifo_sink_error}};
|
|
reset_merged_output = first_write_response && (rdata_fifo_sink_valid || generate_response);
|
|
previous_response_in = reset_merged_output ? current_response : previous_response;
|
|
response_merged = current_response >= previous_response ? current_response: previous_response_in;
|
|
end
|
|
|
|
always_ff @(posedge clk or posedge reset) begin
|
|
if (reset) begin
|
|
previous_response <= 2'b00;
|
|
end
|
|
else begin
|
|
if (rf_sink_valid & (rdata_fifo_sink_valid || generate_response)) begin
|
|
previous_response <= response_merged;
|
|
end
|
|
end
|
|
end
|
|
end else begin : response_merging_read_only
|
|
always @* begin
|
|
current_response = generate_response ? 2'b00: rdata_fifo_sink_data[AVS_DATA_W+1:AVS_DATA_W] |
|
|
{2{rdata_fifo_sink_error}};
|
|
response_merged = current_response;
|
|
end
|
|
end
|
|
endgenerate
|
|
|
|
assign generate_response = rf_sink_data[FIFO_DATA_W-1];
|
|
|
|
wire [BYTE_CNT_W-1:0] rf_sink_byte_cnt = rf_sink_data[PKT_BYTE_CNT_H:PKT_BYTE_CNT_L];
|
|
wire rf_sink_compressed = rf_sink_data[PKT_TRANS_COMPRESSED_READ];
|
|
wire [BURSTWRAP_W-1:0] rf_sink_burstwrap = rf_sink_data[PKT_BURSTWRAP_H:PKT_BURSTWRAP_L];
|
|
wire [BURSTSIZE_W-1:0] rf_sink_burstsize = rf_sink_data[PKT_BURST_SIZE_H:PKT_BURST_SIZE_L];
|
|
wire [ADDR_W-1:0] rf_sink_addr = rf_sink_data[PKT_ADDR_H:PKT_ADDR_L];
|
|
// a non posted write response is always completed in 1 cycle. Modify the startofpacket signal to 1'b1 instead of taking whatever is in the rf_fifo
|
|
wire rf_sink_startofpacket_wire = rf_sink_data[PKT_TRANS_WRITE] ? 1'b1 : rf_sink_startofpacket;
|
|
|
|
wire [BYTE_CNT_W-1:0] burst_byte_cnt;
|
|
wire [BURSTWRAP_W-1:0] rp_burstwrap;
|
|
wire [ADDR_W-1:0] rp_address;
|
|
wire rp_is_compressed;
|
|
wire ready_for_response;
|
|
|
|
// ------------------------------------------------------------------
|
|
// We're typically ready for a response if the network is ready. There
|
|
// is one exception:
|
|
//
|
|
// If the slave issues write responses, we only issue a merged response on
|
|
// the final sub-burst. As a result, we only care about response channel
|
|
// availability on the final burst when we send out the merged response.
|
|
// ------------------------------------------------------------------
|
|
assign ready_for_response = (USE_WRITERESPONSE) ?
|
|
rp_ready || (rf_sink_data[PKT_TRANS_WRITE] && !last_write_response) || rf_sink_data[PKT_TRANS_POSTED]:
|
|
rp_ready;
|
|
|
|
// ------------------------------------------------------------------
|
|
// Backpressure the readdata fifo if we're supposed to synthesize a response.
|
|
// This may be a read response (for suppressed reads) or a write response
|
|
// (for non-posted writes).
|
|
// ------------------------------------------------------------------
|
|
assign rdata_fifo_sink_ready = rdata_fifo_sink_valid & ready_for_response & ~(rf_sink_valid & generate_response);
|
|
|
|
always @* begin
|
|
// By default, return all fields...
|
|
rp_data = rf_sink_data[ST_DATA_W - 1 : 0];
|
|
|
|
// ... and override specific fields.
|
|
rp_data[PKT_DATA_H :PKT_DATA_L] = rdata_fifo_sink_data[AVS_DATA_W-1:0];
|
|
// Assignments directly from the response fifo.
|
|
rp_data[PKT_TRANS_POSTED] = rf_sink_data[PKT_TRANS_POSTED];
|
|
rp_data[PKT_TRANS_WRITE] = rf_sink_data[PKT_TRANS_WRITE];
|
|
rp_data[PKT_SRC_ID_H :PKT_SRC_ID_L] = rf_sink_data[PKT_DEST_ID_H : PKT_DEST_ID_L];
|
|
rp_data[PKT_DEST_ID_H:PKT_DEST_ID_L] = rf_sink_data[PKT_SRC_ID_H : PKT_SRC_ID_L];
|
|
rp_data[PKT_BYTEEN_H :PKT_BYTEEN_L] = rf_sink_data[PKT_BYTEEN_H : PKT_BYTEEN_L];
|
|
rp_data[PKT_PROTECTION_H:PKT_PROTECTION_L] = rf_sink_data[PKT_PROTECTION_H:PKT_PROTECTION_L];
|
|
|
|
// Burst uncompressor assignments
|
|
rp_data[PKT_ADDR_H :PKT_ADDR_L] = rp_address;
|
|
rp_data[PKT_BURSTWRAP_H:PKT_BURSTWRAP_L] = rp_burstwrap;
|
|
rp_data[PKT_BYTE_CNT_H:PKT_BYTE_CNT_L] = burst_byte_cnt;
|
|
rp_data[PKT_TRANS_READ] = rf_sink_data[PKT_TRANS_READ] | rf_sink_data[PKT_TRANS_COMPRESSED_READ];
|
|
rp_data[PKT_TRANS_COMPRESSED_READ] = rp_is_compressed;
|
|
|
|
rp_data[PKT_RESPONSE_STATUS_H:PKT_RESPONSE_STATUS_L] = response_merged;
|
|
rp_data[PKT_BURST_SIZE_H:PKT_BURST_SIZE_L] = uncompressor_burstsize;
|
|
// bounce the original size back to the master untouched
|
|
rp_data[PKT_ORI_BURST_SIZE_H:PKT_ORI_BURST_SIZE_L] = rf_sink_data[PKT_ORI_BURST_SIZE_H:PKT_ORI_BURST_SIZE_L];
|
|
end
|
|
|
|
// ------------------------------------------------------------------
|
|
// Note: the burst uncompressor may be asked to generate responses for
|
|
// write packets; these are treated the same as single-cycle uncompressed
|
|
// reads.
|
|
// ------------------------------------------------------------------
|
|
altera_merlin_burst_uncompressor #(
|
|
.ADDR_W (ADDR_W),
|
|
.BURSTWRAP_W (BURSTWRAP_W),
|
|
.BYTE_CNT_W (BYTE_CNT_W),
|
|
.PKT_SYMBOLS (PKT_SYMBOLS),
|
|
.BURST_SIZE_W (BURSTSIZE_W)
|
|
) uncompressor (
|
|
.clk (clk),
|
|
.reset (reset),
|
|
.sink_startofpacket (rf_sink_startofpacket_wire),
|
|
.sink_endofpacket (rf_sink_endofpacket),
|
|
.sink_valid (rf_sink_valid & (rdata_fifo_sink_valid | generate_response)),
|
|
.sink_ready (rf_sink_ready),
|
|
.sink_addr (rf_sink_addr),
|
|
.sink_burstwrap (rf_sink_burstwrap),
|
|
.sink_byte_cnt (rf_sink_byte_cnt),
|
|
.sink_is_compressed (rf_sink_compressed),
|
|
.sink_burstsize (rf_sink_burstsize),
|
|
|
|
.source_startofpacket (rp_startofpacket),
|
|
.source_endofpacket (rp_endofpacket),
|
|
.source_valid (uncompressor_source_valid),
|
|
.source_ready (ready_for_response),
|
|
.source_addr (rp_address),
|
|
.source_burstwrap (rp_burstwrap),
|
|
.source_byte_cnt (burst_byte_cnt),
|
|
.source_is_compressed (rp_is_compressed),
|
|
.source_burstsize (uncompressor_burstsize)
|
|
);
|
|
|
|
//--------------------------------------
|
|
// Assertion: In case slave support response. The slave needs return response in order
|
|
// Ex: non-posted write followed by a read: write response must complete before read data
|
|
//--------------------------------------
|
|
// synthesis translate_off
|
|
ERROR_write_response_and_read_response_cannot_happen_same_time:
|
|
assert property ( @(posedge clk)
|
|
disable iff (reset) !(m0_writeresponsevalid && m0_readdatavalid)
|
|
);
|
|
|
|
// synthesis translate_on
|
|
endmodule
|
|
|