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dgisselq |
///////////////////////////////////////////////////////////////////////////
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//
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// Filename: zipsystem.v
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//
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// Project: Zip CPU -- a small, lightweight, RISC CPU soft core
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//
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// Purpose: This portion of the ZIP CPU implements a number of soft
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// peripherals to the CPU nearby its CORE. The functionality
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// sits on the data bus, and does not include any true
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// external hardware peripherals. The peripherals included here
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// include:
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//
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//
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// Local interrupt controller--for any/all of the interrupts generated
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// here. This would include a pin for interrupts generated
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// elsewhere, so this interrupt controller could be a master
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// handling all interrupts. My interrupt controller would work
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// for this purpose.
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//
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// The ZIP-CPU supports only one interrupt because, as I understand
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// modern systems (Linux), they tend to send all interrupts to the
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// same interrupt vector anyway. Hence, that's what we do here.
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//
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// Bus Error interrupts -- generates an interrupt any time the wishbone
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// bus produces an error on a given access, for whatever purpose
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// also records the address on the bus at the time of the error.
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//
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// Trap instructions
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// Writing to this "register" will always create an interrupt.
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// After the interrupt, this register may be read to see what
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// value had been written to it.
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//
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// Bit reverse register ... ?
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//
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// (Potentially an eventual floating point co-processor ...)
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//
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// Real-time clock
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//
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// Interval timer(s) (Count down from fixed value, and either stop on
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// zero, or issue an interrupt and restart automatically on zero)
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// These can be implemented as watchdog timers if desired--the
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// only difference is that a watchdog timer's interrupt feeds the
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// reset line instead of the processor interrupt line.
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//
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// Watch-dog timer: this is the same as an interval timer, only it's
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// interrupt/time-out line is wired to the reset line instead of
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// the interrupt line of the CPU.
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//
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// ROM Memory map
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// Set a register to control this map, and a DMA will begin to
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// fill this memory from a slower FLASH. Once filled, accesses
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// will be from this memory instead of
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//
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//
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// Doing some market comparison, let's look at what peripherals a TI
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// MSP430 might offer: MSP's may have I2C ports, SPI, UART, DMA, ADC,
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// Comparators, 16,32-bit timers, 16x16 or 32x32 timers, AES, BSL,
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// brown-out-reset(s), real-time-clocks, temperature sensors, USB ports,
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// Spi-Bi-Wire, UART Boot-strap Loader (BSL), programmable digital I/O,
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// watchdog-timers,
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//
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// Creator: Dan Gisselquist, Ph.D.
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// Gisselquist Tecnology, LLC
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//
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///////////////////////////////////////////////////////////////////////////
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//
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// Copyright (C) 2015, Gisselquist Technology, LLC
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//
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// This program is free software (firmware): you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as published
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// by the Free Software Foundation, either version 3 of the License, or (at
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// your option) any later version.
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//
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// This program is distributed in the hope that it will be useful, but WITHOUT
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// ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY or
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// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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// for more details.
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//
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// License: GPL, v3, as defined and found on www.gnu.org,
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// http://www.gnu.org/licenses/gpl.html
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//
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//
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///////////////////////////////////////////////////////////////////////////
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//
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3 |
dgisselq |
// While I hate adding delays to any bus access, these two are required
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// to make timing close in my Basys-3 design.
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`define DELAY_EXT_BUS
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`define DELAY_DBG_BUS
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//
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//
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// Now, where am I placing all of my peripherals?
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2 |
dgisselq |
`define PERIPHBASE 32'hc0000000
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`define INTCTRL 4'h0 //
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`define WATCHDOG 4'h1 // Interrupt generates reset signal
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`define CACHECTRL 4'h2 // Sets IVEC[0]
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`define CTRINT 4'h3 // Sets IVEC[5]
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`define TIMER_A 4'h4 // Sets IVEC[4]
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`define TIMER_B 4'h5 // Sets IVEC[3]
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`define TIMER_C 4'h6 // Sets IVEC[2]
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`define JIFFIES 4'h7 // Sets IVEC[1]
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`define MSTR_TASK_CTR 4'h8
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`define MSTR_MSTL_CTR 4'h9
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`define MSTR_PSTL_CTR 4'ha
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`define MSTR_ASTL_CTR 4'hb
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`define USER_TASK_CTR 4'hc
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`define USER_MSTL_CTR 4'hd
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`define USER_PSTL_CTR 4'he
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`define USER_ASTL_CTR 4'hf
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`define CACHEBASE 16'hc010 //
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// `define RTC_CLOCK 32'hc0000008 // A global something
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// `define BITREV 32'hc0000003
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//
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// DBGCTRL
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// 10 HALT
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// 9 HALT(ED)
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// 8 STEP (W=1 steps, and returns to halted)
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// 7 INTERRUPT-FLAG
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// 6 RESET_FLAG
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// ADDRESS:
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// 5 PERIPHERAL-BIT
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// [4:0] REGISTER-ADDR
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// DBGDATA
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// read/writes internal registers
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module zipsystem(i_clk, i_rst,
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// Wishbone master interface from the CPU
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o_wb_cyc, o_wb_stb, o_wb_we, o_wb_addr, o_wb_data,
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i_wb_ack, i_wb_stall, i_wb_data,
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// Incoming interrupts
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i_ext_int,
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// Wishbone slave interface for debugging purposes
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i_dbg_cyc, i_dbg_stb, i_dbg_we, i_dbg_addr, i_dbg_data,
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o_dbg_ack, o_dbg_stall, o_dbg_data);
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parameter RESET_ADDRESS=32'h0100000;
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input i_clk, i_rst;
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// Wishbone master
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output wire o_wb_cyc, o_wb_stb, o_wb_we;
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output wire [31:0] o_wb_addr;
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output wire [31:0] o_wb_data;
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input i_wb_ack, i_wb_stall;
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input [31:0] i_wb_data;
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// Incoming interrupts
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input i_ext_int;
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// Wishbone slave
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input i_dbg_cyc, i_dbg_stb, i_dbg_we, i_dbg_addr;
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input [31:0] i_dbg_data;
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output wire o_dbg_ack;
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output wire o_dbg_stall;
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output wire [31:0] o_dbg_data;
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wire [31:0] ext_idata;
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// Delay the debug port by one clock, to meet timing requirements
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wire dbg_cyc, dbg_stb, dbg_we, dbg_addr, dbg_stall;
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wire [31:0] dbg_idata, dbg_odata;
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reg dbg_ack;
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dgisselq |
`ifdef DELAY_DBG_BUS
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2 |
dgisselq |
busdelay #(1,32) wbdelay(i_clk,
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i_dbg_cyc, i_dbg_stb, i_dbg_we, i_dbg_addr, i_dbg_data,
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o_dbg_ack, o_dbg_stall, o_dbg_data,
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dbg_cyc, dbg_stb, dbg_we, dbg_addr, dbg_idata,
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dbg_ack, dbg_stall, dbg_odata);
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dgisselq |
`else
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assign dbg_cyc = i_dbg_cyc;
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assign dbg_stb = i_dbg_stb;
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assign dbg_we = i_dbg_we;
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assign dbg_addr = i_dbg_addr;
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assign dbg_idata = i_dbg_data;
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assign o_dbg_ack = dbg_ack;
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assign o_dbg_stall = dbg_stall;
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assign o_dbg_data = dbg_odata;
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`endif
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2 |
dgisselq |
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//
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//
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//
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wire sys_cyc, sys_stb, sys_we;
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wire [3:0] sys_addr;
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wire [31:0] cpu_addr;
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wire [31:0] sys_data;
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// wire sys_ack, sys_stall;
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//
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// The external debug interface
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//
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// We offer only a limited interface here, requiring a pre-register
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// write to set the local address. This interface allows access to
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// the Zip System on a debug basis only, and not to the rest of the
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// wishbone bus. Further, to access these registers, the control
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// register must first be accessed to both stop the CPU and to
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// set the following address in question. Hence all accesses require
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// two accesses: write the address to the control register (and halt
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// the CPU if not halted), then read/write the data from the data
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// register.
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//
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wire cpu_break;
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reg cmd_reset, cmd_halt, cmd_step;
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reg [5:0] cmd_addr;
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initial cmd_reset = 1'b1;
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initial cmd_halt = 1'b1;
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initial cmd_step = 1'b0;
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always @(posedge i_clk)
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if (i_rst)
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begin
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cmd_halt <= 1'b0;
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cmd_step <= 1'b0;
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cmd_reset<= 1'b0;
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cmd_addr <= 6'h00;
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end else if ((dbg_cyc)&&(dbg_stb)
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&&(dbg_we)&&(~dbg_addr))
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begin
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cmd_halt <= dbg_idata[10];
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cmd_step <= dbg_idata[ 8];
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cmd_reset<= dbg_idata[ 6];
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cmd_addr <= dbg_idata[5:0];
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end else if (cmd_step)
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begin
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cmd_halt <= 1'b1;
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cmd_step <= 1'b0;
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end else if (cpu_break)
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cmd_halt <= 1'b1;
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wire cpu_reset;
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assign cpu_reset = (i_rst)||(cmd_reset)||(wdt_reset);
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wire cpu_halt, cpu_dbg_stall;
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assign cpu_halt = (cmd_halt)&&(~cmd_step);
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wire [31:0] pic_data;
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wire [31:0] cmd_data;
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assign cmd_data = { 21'h00, cmd_halt, (~cpu_dbg_stall), 1'b0, pic_data[15],
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cpu_reset, cmd_addr };
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`ifdef USE_TRAP
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//
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// The TRAP peripheral
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//
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wire trap_ack, trap_stall, trap_int;
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wire [31:0] trap_data;
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ziptrap trapp(i_clk,
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sys_cyc, (sys_stb)&&(sys_addr == `TRAP_ADDR), sys_we,
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sys_data,
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trap_ack, trap_stall, trap_data, trap_int);
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`endif
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//
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// The WATCHDOG Timer
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//
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wire wdt_ack, wdt_stall, wdt_reset;
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wire [31:0] wdt_data;
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ziptimer watchdog(i_clk, cpu_reset, ~cmd_halt,
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sys_cyc, ((sys_stb)&&(sys_addr == `WATCHDOG)), sys_we,
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sys_data,
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wdt_ack, wdt_stall, wdt_data, wdt_reset);
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//
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// The Flash Cache, a pre-read cache to memory that can be used to
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// create a fast memory access area
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//
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wire cache_int;
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wire [31:0] cache_data;
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wire cache_stb, cache_ack, cache_stall;
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wire fc_cyc, fc_stb, fc_we, fc_ack, fc_stall;
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wire [31:0] fc_data, fc_addr;
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flashcache #(10) manualcache(i_clk,
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sys_cyc, cache_stb,
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((sys_stb)&&(sys_addr == `CACHECTRL)),
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sys_we, cpu_addr[9:0], sys_data,
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cache_ack, cache_stall, cache_data,
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// Need the outgoing CACHE wishbone bus
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fc_cyc, fc_stb, fc_we, fc_addr, fc_data,
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fc_ack, fc_stall, ext_idata,
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// Cache interrupt, for upon completion
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cache_int);
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// Counters -- for performance measurement and accounting
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//
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// Here's the stuff we'll be counting ....
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//
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wire cpu_mem_stall, cpu_pf_stall, cpu_alu_stall;
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//
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// The master counters will, in general, not be reset. They'll be used
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// for an overall counter.
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//
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// Master task counter
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wire mtc_ack, mtc_stall, mtc_int;
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wire [31:0] mtc_data;
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zipcounter mtask_ctr(i_clk, (~cmd_halt), sys_cyc,
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(sys_stb)&&(sys_addr == `MSTR_TASK_CTR),
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sys_we, sys_data,
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mtc_ack, mtc_stall, mtc_data, mtc_int);
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// Master Memory-Stall counter
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wire mmc_ack, mmc_stall, mmc_int;
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wire [31:0] mmc_data;
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zipcounter mmstall_ctr(i_clk,(~cmd_halt)&&(cpu_mem_stall), sys_cyc,
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(sys_stb)&&(sys_addr == `MSTR_MSTL_CTR),
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sys_we, sys_data,
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mmc_ack, mmc_stall, mmc_data, mmc_int);
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// Master PreFetch-Stall counter
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wire mpc_ack, mpc_stall, mpc_int;
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wire [31:0] mpc_data;
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zipcounter mpstall_ctr(i_clk,(~cmd_halt)&&(cpu_pf_stall), sys_cyc,
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(sys_stb)&&(sys_addr == `MSTR_PSTL_CTR),
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sys_we, sys_data,
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mpc_ack, mpc_stall, mpc_data, mpc_int);
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// Master ALU-Stall counter
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wire mac_ack, mac_stall, mac_int;
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wire [31:0] mac_data;
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zipcounter mastall_ctr(i_clk,(~cmd_halt)&&(cpu_alu_stall), sys_cyc,
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(sys_stb)&&(sys_addr == `MSTR_ASTL_CTR),
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sys_we, sys_data,
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mac_ack, mac_stall, mac_data, mac_int);
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//
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// The user counters are different from those of the master. They will
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// be reset any time a task is given control of the CPU.
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//
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// User task counter
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wire utc_ack, utc_stall, utc_int;
|
324 |
|
|
wire [31:0] utc_data;
|
325 |
|
|
zipcounter utask_ctr(i_clk,(~cmd_halt), sys_cyc,
|
326 |
|
|
(sys_stb)&&(sys_addr == `USER_TASK_CTR),
|
327 |
|
|
sys_we, sys_data,
|
328 |
|
|
utc_ack, utc_stall, utc_data, utc_int);
|
329 |
|
|
|
330 |
|
|
// User Memory-Stall counter
|
331 |
|
|
wire umc_ack, umc_stall, umc_int;
|
332 |
|
|
wire [31:0] umc_data;
|
333 |
|
|
zipcounter umstall_ctr(i_clk,(~cmd_halt)&&(cpu_mem_stall), sys_cyc,
|
334 |
|
|
(sys_stb)&&(sys_addr == `USER_MSTL_CTR),
|
335 |
|
|
sys_we, sys_data,
|
336 |
|
|
umc_ack, umc_stall, umc_data, umc_int);
|
337 |
|
|
|
338 |
|
|
// User PreFetch-Stall counter
|
339 |
|
|
wire upc_ack, upc_stall, upc_int;
|
340 |
|
|
wire [31:0] upc_data;
|
341 |
|
|
zipcounter upstall_ctr(i_clk,(~cmd_halt)&&(cpu_pf_stall), sys_cyc,
|
342 |
|
|
(sys_stb)&&(sys_addr == `USER_PSTL_CTR),
|
343 |
|
|
sys_we, sys_data,
|
344 |
|
|
upc_ack, upc_stall, upc_data, upc_int);
|
345 |
|
|
|
346 |
|
|
// User ALU-Stall counter
|
347 |
|
|
wire uac_ack, uac_stall, uac_int;
|
348 |
|
|
wire [31:0] uac_data;
|
349 |
|
|
zipcounter uastall_ctr(i_clk,(~cmd_halt)&&(cpu_alu_stall), sys_cyc,
|
350 |
|
|
(sys_stb)&&(sys_addr == `USER_ASTL_CTR),
|
351 |
|
|
sys_we, sys_data,
|
352 |
|
|
uac_ack, uac_stall, uac_data, uac_int);
|
353 |
|
|
|
354 |
|
|
// A little bit of pre-cleanup (actr = accounting counters)
|
355 |
|
|
wire actr_ack, actr_stall;
|
356 |
|
|
wire [31:0] actr_data;
|
357 |
|
|
assign actr_ack = ((mtc_ack | mmc_ack | mpc_ack | mac_ack)
|
358 |
|
|
|(utc_ack | umc_ack | upc_ack | uac_ack));
|
359 |
|
|
assign actr_stall = ((mtc_stall | mmc_stall | mpc_stall | mac_stall)
|
360 |
|
|
|(utc_stall | umc_stall | upc_stall|uac_stall));
|
361 |
|
|
assign actr_data = ((mtc_ack) ? mtc_data
|
362 |
|
|
: ((mmc_ack) ? mmc_data
|
363 |
|
|
: ((mpc_ack) ? mpc_data
|
364 |
|
|
: ((mac_ack) ? mac_data
|
365 |
|
|
: ((utc_ack) ? utc_data
|
366 |
|
|
: ((umc_ack) ? umc_data
|
367 |
|
|
: ((upc_ack) ? upc_data
|
368 |
|
|
: uac_data)))))));
|
369 |
|
|
|
370 |
|
|
|
371 |
|
|
|
372 |
|
|
//
|
373 |
|
|
// Counter Interrupt controller
|
374 |
|
|
//
|
375 |
|
|
reg ctri_ack;
|
376 |
|
|
wire ctri_stall, ctri_int, ctri_sel;
|
377 |
|
|
wire [7:0] ctri_vector;
|
378 |
|
|
wire [31:0] ctri_data;
|
379 |
|
|
assign ctri_sel = (sys_cyc)&&(sys_stb)&&(sys_addr == `CTRINT);
|
380 |
|
|
assign ctri_vector = { mtc_int, mmc_int, mpc_int, mac_int,
|
381 |
|
|
utc_int, umc_int, upc_int, uac_int };
|
382 |
|
|
icontrol #(8) ctri(i_clk, cpu_reset, (ctri_sel)&&(sys_addr==`CTRINT),
|
383 |
|
|
sys_data, ctri_data, ctri_vector, ctri_int);
|
384 |
|
|
always @(posedge i_clk)
|
385 |
|
|
ctri_ack <= ctri_sel;
|
386 |
|
|
|
387 |
|
|
|
388 |
|
|
//
|
389 |
|
|
// Timer A
|
390 |
|
|
//
|
391 |
|
|
wire tma_ack, tma_stall, tma_int;
|
392 |
|
|
wire [31:0] tma_data;
|
393 |
|
|
ziptimer timer_a(i_clk, cpu_reset, ~cmd_halt,
|
394 |
|
|
sys_cyc, (sys_stb)&&(sys_addr == `TIMER_A), sys_we,
|
395 |
|
|
sys_data,
|
396 |
|
|
tma_ack, tma_stall, tma_data, tma_int);
|
397 |
|
|
|
398 |
|
|
//
|
399 |
|
|
// Timer B
|
400 |
|
|
//
|
401 |
|
|
wire tmb_ack, tmb_stall, tmb_int;
|
402 |
|
|
wire [31:0] tmb_data;
|
403 |
|
|
ziptimer timer_b(i_clk, cpu_reset, ~cmd_halt,
|
404 |
|
|
sys_cyc, (sys_stb)&&(sys_addr == `TIMER_B), sys_we,
|
405 |
|
|
sys_data,
|
406 |
|
|
tmb_ack, tmb_stall, tmb_data, tmb_int);
|
407 |
|
|
|
408 |
|
|
//
|
409 |
|
|
// Timer C
|
410 |
|
|
//
|
411 |
|
|
wire tmc_ack, tmc_stall, tmc_int;
|
412 |
|
|
wire [31:0] tmc_data;
|
413 |
|
|
ziptimer timer_c(i_clk, cpu_reset, ~cmd_halt,
|
414 |
|
|
sys_cyc, (sys_stb)&&(sys_addr == `TIMER_C), sys_we,
|
415 |
|
|
sys_data,
|
416 |
|
|
tmc_ack, tmc_stall, tmc_data, tmc_int);
|
417 |
|
|
|
418 |
|
|
//
|
419 |
|
|
// JIFFIES
|
420 |
|
|
//
|
421 |
|
|
wire jif_ack, jif_stall, jif_int;
|
422 |
|
|
wire [31:0] jif_data;
|
423 |
|
|
zipjiffies jiffies(i_clk, ~cmd_halt,
|
424 |
|
|
sys_cyc, (sys_stb)&&(sys_addr == `JIFFIES), sys_we,
|
425 |
|
|
sys_data,
|
426 |
|
|
jif_ack, jif_stall, jif_data, jif_int);
|
427 |
|
|
|
428 |
|
|
//
|
429 |
|
|
// The programmable interrupt controller peripheral
|
430 |
|
|
//
|
431 |
|
|
wire pic_interrupt;
|
432 |
|
|
wire [6:0] int_vector;
|
433 |
|
|
assign int_vector = { i_ext_int, ctri_int, tma_int, tmb_int, tmc_int,
|
434 |
|
|
jif_int, cache_int };
|
435 |
|
|
icontrol #(7) pic(i_clk, cpu_reset,
|
436 |
|
|
(sys_cyc)&&(sys_stb)&&(sys_we)
|
437 |
|
|
&&(sys_addr==`INTCTRL),
|
438 |
|
|
sys_data, pic_data,
|
439 |
|
|
int_vector, pic_interrupt);
|
440 |
|
|
reg pic_ack;
|
441 |
|
|
always @(posedge i_clk)
|
442 |
|
|
pic_ack <= (sys_cyc)&&(sys_stb)&&(sys_addr == `INTCTRL);
|
443 |
|
|
|
444 |
|
|
//
|
445 |
|
|
// The CPU itself
|
446 |
|
|
//
|
447 |
|
|
wire cpu_cyc, cpu_stb, cpu_we, cpu_dbg_we;
|
448 |
|
|
wire [31:0] cpu_data, wb_data;
|
449 |
|
|
wire cpu_ack, cpu_stall;
|
450 |
|
|
wire [31:0] cpu_dbg_data;
|
451 |
|
|
assign cpu_dbg_we = ((dbg_cyc)&&(dbg_stb)&&(~cmd_addr[5])
|
452 |
|
|
&&(dbg_we)&&(dbg_addr));
|
453 |
|
|
zipcpu #(RESET_ADDRESS) thecpu(i_clk, cpu_reset, pic_interrupt,
|
454 |
|
|
cpu_halt, cmd_addr[4:0], cpu_dbg_we,
|
455 |
|
|
dbg_idata, cpu_dbg_stall, cpu_dbg_data,
|
456 |
|
|
cpu_break,
|
457 |
|
|
cpu_cyc, cpu_stb, cpu_we, cpu_addr, cpu_data,
|
458 |
|
|
cpu_ack, cpu_stall, wb_data,
|
459 |
|
|
cpu_mem_stall, cpu_pf_stall, cpu_alu_stall);
|
460 |
|
|
|
461 |
|
|
// Now, arbitrate the bus ... first for the local peripherals
|
462 |
|
|
assign sys_cyc = (cpu_cyc)||((cpu_halt)&&(~cpu_dbg_stall)&&(dbg_cyc));
|
463 |
|
|
assign sys_stb = (cpu_cyc)
|
464 |
|
|
? ((cpu_stb)&&(cpu_addr[31:4] == 28'hc000000))
|
465 |
|
|
: ((dbg_stb)&&(dbg_addr)&&(cmd_addr[5]));
|
466 |
|
|
|
467 |
|
|
assign sys_we = (cpu_cyc) ? cpu_we : dbg_we;
|
468 |
|
|
assign sys_addr= (cpu_cyc) ? cpu_addr[3:0] : cmd_addr[3:0];
|
469 |
|
|
assign sys_data= (cpu_cyc) ? cpu_data : dbg_idata;
|
470 |
|
|
assign cache_stb=((cpu_cyc)&&(cpu_stb)&&(cpu_addr[31:16]==`CACHEBASE));
|
471 |
|
|
|
472 |
|
|
// Return debug response values
|
473 |
|
|
assign dbg_odata = (~dbg_addr)?cmd_data
|
474 |
|
|
:((~cmd_addr[5])?cpu_dbg_data : wb_data);
|
475 |
|
|
initial dbg_ack = 1'b0;
|
476 |
|
|
always @(posedge i_clk)
|
477 |
|
|
dbg_ack <= (dbg_cyc)&&(dbg_stb)&&
|
478 |
|
|
((~dbg_addr)||((cpu_halt)&&(~cpu_dbg_stall)));
|
479 |
|
|
assign dbg_stall=(dbg_addr)&&(dbg_cyc)
|
480 |
|
|
&&((cpu_cyc)||(~cpu_halt)||(cpu_dbg_stall));
|
481 |
|
|
|
482 |
|
|
// Now for the external wishbone bus
|
483 |
|
|
// Need to arbitrate between the flash cache and the CPU
|
484 |
|
|
// The way this works, though, the CPU will stall once the flash
|
485 |
|
|
// cache gets access to the bus--the CPU will be stuck until the
|
486 |
|
|
// flash cache is finished with the bus.
|
487 |
|
|
wire ext_cyc, ext_stb, ext_we;
|
488 |
|
|
wire cpu_ext_ack, cpu_ext_stall, ext_ack, ext_stall;
|
489 |
|
|
wire [31:0] ext_addr, ext_odata;
|
490 |
|
|
wbarbiter #(32,32) flashvcpu(i_clk, i_rst,
|
491 |
|
|
fc_addr, fc_data, fc_we, fc_stb, fc_cyc,
|
492 |
|
|
fc_ack, fc_stall,
|
493 |
|
|
cpu_addr, cpu_data, cpu_we,
|
494 |
|
|
((cpu_stb)&&(~sys_stb)&&(~cache_stb)),
|
495 |
|
|
cpu_cyc, cpu_ext_ack, cpu_ext_stall,
|
496 |
|
|
ext_addr, ext_odata, ext_we, ext_stb,
|
497 |
|
|
ext_cyc, ext_ack, ext_stall);
|
498 |
|
|
|
499 |
3 |
dgisselq |
`ifdef DELAY_EXT_BUS
|
500 |
2 |
dgisselq |
busdelay #(32,32) extbus(i_clk,
|
501 |
|
|
ext_cyc, ext_stb, ext_we, ext_addr, ext_odata,
|
502 |
|
|
ext_ack, ext_stall, ext_idata,
|
503 |
|
|
o_wb_cyc, o_wb_stb, o_wb_we, o_wb_addr, o_wb_data,
|
504 |
|
|
i_wb_ack, i_wb_stall, i_wb_data);
|
505 |
3 |
dgisselq |
`else
|
506 |
|
|
assign o_wb_cyc = ext_cyc;
|
507 |
|
|
assign o_wb_stb = ext_stb;
|
508 |
|
|
assign o_wb_we = ext_we;
|
509 |
|
|
assign o_wb_addr = ext_addr;
|
510 |
|
|
assign o_wb_data = ext_odata;
|
511 |
|
|
assign ext_ack = i_wb_ack;
|
512 |
|
|
assign ext_stall = i_wb_stall;
|
513 |
|
|
assign ext_idata = i_wb_data;
|
514 |
|
|
`endif
|
515 |
2 |
dgisselq |
|
516 |
|
|
wire tmr_ack;
|
517 |
|
|
assign tmr_ack = (tma_ack|tmb_ack|tmc_ack|jif_ack);
|
518 |
|
|
wire [31:0] tmr_data;
|
519 |
|
|
assign tmr_data = (tma_ack)?tma_data
|
520 |
|
|
:(tmb_ack ? tmb_data
|
521 |
|
|
:(tmc_ack ? tmc_data
|
522 |
|
|
:jif_data));
|
523 |
|
|
assign wb_data = (tmr_ack|wdt_ack)?((tmr_ack)?tmr_data:wdt_data)
|
524 |
|
|
:((actr_ack|cache_ack)?((actr_ack)?actr_data:cache_data)
|
525 |
|
|
:((pic_ack|ctri_ack)?((pic_ack)?pic_data:ctri_data)
|
526 |
|
|
:(ext_idata)));
|
527 |
|
|
|
528 |
|
|
assign cpu_stall = (tma_stall | tmb_stall | tmc_stall | jif_stall
|
529 |
|
|
| wdt_stall | cache_stall
|
530 |
|
|
| cpu_ext_stall);
|
531 |
|
|
assign cpu_ack = (tmr_ack|wdt_ack|cache_ack|cpu_ext_ack|ctri_ack|actr_ack|pic_ack);
|
532 |
|
|
endmodule
|