Tridora-CPU/tridoracpu/tridoracpu.srcs/top.v

312 lines
11 KiB
Verilog

`timescale 1ns / 1ps
// either define clock as clk (100MHz on Arty)
// or as clk_1hz for debugging
`define clock cpuclk
//`define clkfreq 83333333
`define clkfreq 76923076
//`define clock clk
//`define clkfreq 100000000
//`define clock clk_1hz
`define ENABLE_VGAFB
`define ENABLE_MICROSD
`define ENABLE_TDRAUDIO
module top(
input wire clk,
input wire rst,
output wire led0,
output wire led1,
output wire led2,
output wire led3,
input wire uart_txd_in,
output wire uart_rxd_out,
// DDR3 SDRAM
inout wire [15:0] ddr3_dq,
inout wire [1:0] ddr3_dqs_n,
inout wire [1:0] ddr3_dqs_p,
output wire [13:0] ddr3_addr,
output wire [2:0] ddr3_ba,
output wire ddr3_ras_n,
output wire ddr3_cas_n,
output wire ddr3_we_n,
output wire ddr3_reset_n,
output wire [0:0] ddr3_ck_p,
output wire [0:0] ddr3_ck_n,
output wire [0:0] ddr3_cke,
output wire [0:0] ddr3_cs_n,
output wire [1:0] ddr3_dm,
output wire [0:0] ddr3_odt
`ifdef ENABLE_VGAFB
,
output wire [3:0] VGA_R,
output wire [3:0] VGA_G,
output wire [3:0] VGA_B,
output wire VGA_HS_O,
output wire VGA_VS_O
`endif
`ifdef ENABLE_MICROSD
,
output wire sd_cs_n,
output wire sd_mosi,
input wire sd_miso,
output wire sd_sck,
input wire sd_cd
`endif
`ifdef ENABLE_TDRAUDIO
,
output wire amp2_ain,
output wire amp2_gain,
output wire amp2_shutdown_n
`endif
);
reg clk_1hz;
reg [31:0] counter;
localparam ADDR_WIDTH = 32, WIDTH = 32,
ROMADDR_WIDTH = 11, IOADDR_WIDTH = 11, IOADDR_SEL = 4;
(* KEEP *) wire [ADDR_WIDTH-1:0] mem_addr;
wire [WIDTH-1:0] mem_read_data;
wire [WIDTH-1:0] mem_write_data;
(* KEEP *) wire mem_wait;
assign led0 = mem_wait;
(* KEEP *) wire mem_read_enable;
(* KEEP *) wire mem_write_enable;
(* KEEP *) wire io_enable;
wire [WIDTH-1:0] io_rd_data;
wire [IOADDR_SEL-1:0] io_slot = mem_addr[IOADDR_WIDTH-1:IOADDR_WIDTH-IOADDR_SEL];
wire irq;
wire cpuclk, cpuclk_locked;
wire dram_refclk200;
wire pixclk;
cpu_clkgen cpuclk_0(~rst, clk, cpuclk, dram_refclk200, pixclk, cpuclk_locked);
// DRAM --------------------------------------------------------------------------
wire [ADDR_WIDTH-1:0] dram_addr;
wire [WIDTH-1:0] dram_read_data, dram_write_data;
wire dram_read_enable, dram_write_enable, dram_wait;
(* KEEP *) wire dram_read_ins;
dram_bridge dram_bridge0 (dram_addr,
dram_read_data, dram_write_data, dram_read_enable, dram_write_enable,
dram_read_ins, dram_wait,
rst, cpuclk, dram_refclk200,
ddr3_dq, ddr3_dqs_n, ddr3_dqs_p, ddr3_addr,
ddr3_ba, ddr3_ras_n, ddr3_cas_n, ddr3_we_n,
ddr3_reset_n, ddr3_ck_p, ddr3_ck_n, ddr3_cke,
ddr3_cs_n, ddr3_dm, ddr3_odt);
mem #(.ADDR_WIDTH(ADDR_WIDTH), .DATA_WIDTH(WIDTH)) mem0(
.clk(`clock), .rst_n(rst), .addr(mem_addr),
.data_out(mem_read_data), .read_enable(mem_read_enable),
.data_in(mem_write_data), .write_enable(mem_write_enable),
.io_enable(io_enable),
.io_rd_data(io_rd_data),
.mem_wait(mem_wait),
.dram_addr(dram_addr),
.dram_read_data(dram_read_data),
.dram_write_data(dram_write_data),
.dram_read_enable(dram_read_enable),
.dram_write_enable(dram_write_enable),
.dram_wait(dram_wait)
);
`ifdef ENABLE_VGAFB
localparam FB_ADDR_WIDTH = 14;
wire [FB_ADDR_WIDTH-1:0] fb_rd_addr;
wire [FB_ADDR_WIDTH-1:0] fb_wr_addr;
wire [WIDTH-1:0] fb_rd_data;
wire [WIDTH-1:0] fb_wr_data;
wire fb_rd_en, fb_wr_en;
wire fb_cs_en = io_enable && (io_slot == 2);
assign fb_rd_en = fb_cs_en && mem_read_enable;
assign fb_wr_en = fb_cs_en && mem_write_enable;
assign fb_wr_data = mem_write_data;
vgafb vgafb0(`clock, pixclk, rst,
mem_addr[3:0], fb_rd_data, fb_wr_data,
fb_rd_en, fb_wr_en,
VGA_HS_O, VGA_VS_O, VGA_R, VGA_G, VGA_B);
`endif
// SPI SD card controller -------------------------------------------------------------------
`ifdef ENABLE_MICROSD
wire [7:0] spi_tx_data;
(*KEEP*) wire [7:0] spi_rx_data;
wire spi_tx_ready; // ready to transmit new data
wire spi_tx_empty; // tx fifo is empty
wire spi_rx_avail; // a byte has been received
wire spi_rx_ovr; // receiver overrun
wire spi_tx_write; // write strobe
wire spi_rx_read; // read strobe (clears rx_avail)
wire spi_card_detect; // true is card is present
wire spi_card_changed; // card_detect signal has changed
wire spi_card_busy; // card is busy (MISO/DO is 0)
wire spi_ctrl_write; // set the following flags
wire spi_rx_filter_en; // set to wait for start bit (1-to-0) when receiving
wire spi_txrx_en; // enable transmitter and receiver
wire spi_sclk_f_en; // enable spi clock without transceiver
wire spi_sclk_div_wr; // set clock divider from tx_data
wire spi_cs; // cs signal for spi controller
wire [WIDTH-1:0] spi_rd_data;
assign spi_cs = io_enable && (io_slot == 1);
// spi read data: [ 0,...,0,cd,cc,cb,tr,te,ra,ro,d,d,d,d,d,d,d,d ]
// cd = card detect, cc = card changed, cb = card busy,
// tr = transmitter ready, te = tx fifo empty,
// ra = received byte available, ro = receive overrun, d = received byte
assign spi_rd_data =
{ {WIDTH-15{1'b0}}, spi_card_detect, spi_card_changed, spi_card_busy,
spi_tx_ready, spi_tx_empty,
spi_rx_avail, spi_rx_ovr, spi_rx_data };
// spi write data: [ 0,...,0,CW,CF,Cx,Cc,Cd,DR,DW,d,d,d,d,d,d,d,d ]
// CW = control write, CF = enable receive filter, Cx = enable transceiver,
// Cc = force spi clock on, Cd = write clock divider,
// DR = read acknowledge, DW = data write, d = byte to be sent
assign spi_ctrl_write = spi_cs && mem_write_enable && mem_write_data[14];
assign spi_rx_filter_en = mem_write_data[13];
assign spi_txrx_en = mem_write_data[12];
assign spi_sclk_f_en = mem_write_data[11];
assign spi_sclk_div_wr = spi_cs && mem_write_enable && mem_write_data[10];
assign spi_rx_read = mem_write_data[9];
assign spi_tx_write = spi_cs && mem_write_enable && mem_write_data[8];
assign spi_tx_data = mem_write_data[7:0];
sdspi sdspi0(.clk(`clock), .reset(~rst),
.tx_data(spi_tx_data), .rx_data(spi_rx_data),
.tx_ready(spi_tx_ready), .tx_empty(spi_tx_empty),
.rx_avail(spi_rx_avail), .rx_ovr(spi_rx_ovr),
.tx_write(spi_tx_write), .rx_read(spi_rx_read),
.card_detect(spi_card_detect), .card_changed(spi_card_changed), .card_busy(spi_card_busy),
// ctrl_write is used with rx_filter_en, txrx_en and spiclk_f_en
.ctrl_write(spi_ctrl_write),
.rx_filter_en(spi_rx_filter_en), .txrx_en(spi_txrx_en), .spiclk_f_en(spi_sclk_f_en),
//
.spiclk_div_wr(spi_sclk_div_wr),
.sd_cs_n(sd_cs_n),
.sd_mosi(sd_mosi), .sd_miso(sd_miso), .sd_sck(sd_sck), .sd_cd(sd_cd));
`endif
// UART -----------------------------------------------------------------------
// uart write data: [ 0, 0, 0, 0, 0, T, C, 0, c, c, c, c, c, c, c, c ]
// T = transmit enable, C = receiver clear, c = 8-bit-character
// uart read data: [ 0, 0, 0, 0, 0, 0, A, B, c, c, c, c, c, c, c, c ]
// A = char available, B = tx busy, c = 8-bit-character
wire uart_cs = io_enable && (io_slot == 0);
wire uart_tx_en = uart_cs && mem_write_enable && mem_write_data[10];
wire uart_rx_clear = uart_cs && mem_write_enable && mem_write_data[9];
wire uart_rx_avail;
wire uart_rx_busy, uart_tx_busy;
wire uart_err;
wire [7:0] uart_rx_data;
wire [7:0] uart_tx_data;
wire [31:0] uart_baud = 32'd115200;
wire [WIDTH-1:0] uart_rd_data;
assign uart_tx_data = mem_write_data[7:0];
assign uart_rd_data = { {WIDTH-10{1'b1}}, uart_rx_avail, uart_tx_busy, uart_rx_data };
wire audio_irq;
buart #(.CLKFREQ(`clkfreq)) uart0(`clock, rst,
uart_baud,
uart_txd_in, uart_rxd_out,
uart_rx_clear, uart_tx_en,
uart_rx_avail, uart_tx_busy,
uart_tx_data, uart_rx_data);
// audio controller
`ifdef ENABLE_TDRAUDIO
wire [WIDTH-1:0] tdraudio_wr_data;
wire [WIDTH-1:0] tdraudio_rd_data;
wire tdraudio_rd_en, tdraudio_wr_en;
wire tdraudio_irq;
wire tdraudio_cs_en = io_enable && (io_slot == 4);
assign tdraudio_rd_en = tdraudio_cs_en && mem_read_enable;
assign tdraudio_wr_en = tdraudio_cs_en && mem_write_enable;
assign tdraudio_wr_data = mem_write_data;
tdraudio tdraudio0(`clock, ~rst,
mem_addr[6:0],
tdraudio_rd_data,
tdraudio_wr_data,
tdraudio_rd_en,
tdraudio_wr_en,
tdraudio_irq,
amp2_ain, amp2_gain, amp2_shutdown_n);
assign audio_irq = tdraudio_irq;
`endif
// interrupt controller
reg timer_tick;
reg[23:0] tick_count;
wire [2:0] irq_in = { audio_irq, timer_tick, uart_rx_avail };
wire [2:0] irqc_rd_data0;
wire [WIDTH-1:0] irqc_rd_data = { tick_count, 5'b0, irqc_rd_data0 };
wire irqc_seten = mem_write_data[7];
wire irqc_cs = io_enable && (io_slot == 3);
assign io_rd_data = (io_slot == 0) ? uart_rd_data :
`ifdef ENABLE_MICROSD
(io_slot == 1) ? spi_rd_data :
`endif
`ifdef ENABLE_VGAFB
(io_slot == 2) ? fb_rd_data :
`endif
(io_slot == 3) ? irqc_rd_data:
`ifdef ENABLE_TDRAUDIO
(io_slot == 4) ? tdraudio_rd_data:
`endif
-1;
// CPU -----------------------------------------------------------------
stackcpu cpu0(.clk(`clock), .rst(rst), .irq(irq),
.addr(mem_addr),
.data_in(mem_read_data), .read_enable(mem_read_enable),
.read_ins(dram_read_ins),
.data_out(mem_write_data), .write_enable(mem_write_enable),
.mem_wait(mem_wait),
.debug1(led1), .debug2(led2), .debug3(led3));
// Interrupt Controller
irqctrl irqctrl0(`clock, irq_in, irqc_cs, mem_write_enable,
irqc_seten, irqc_rd_data0,
irq);
// count clock ticks
// generate interrupt every 20nth of a second
always @ (posedge `clock)
begin
counter <= counter + 1;
if (counter >= (`clkfreq/20))
begin
counter <= 0;
timer_tick <= 1;
tick_count <= tick_count + 1'b1;
end
else
begin
timer_tick <= 0;
end
end
endmodule