diff options
Diffstat (limited to 'usrp2')
-rw-r--r-- | usrp2/opencores/spi/rtl/verilog/spi_top16.v | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/usrp2/opencores/spi/rtl/verilog/spi_top16.v b/usrp2/opencores/spi/rtl/verilog/spi_top16.v new file mode 100644 index 000000000..ee808a8ab --- /dev/null +++ b/usrp2/opencores/spi/rtl/verilog/spi_top16.v @@ -0,0 +1,182 @@ + +// Modified 2010 by Matt Ettus to remove old verilog style and +// allow 16-bit operation + +////////////////////////////////////////////////////////////////////// +//// //// +//// spi_top.v //// +//// //// +//// This file is part of the SPI IP core project //// +//// http://www.opencores.org/projects/spi/ //// +//// //// +//// Author(s): //// +//// - Simon Srot (simons@opencores.org) //// +//// //// +//// All additional information is avaliable in the Readme.txt //// +//// file. //// +//// //// +////////////////////////////////////////////////////////////////////// +//// //// +//// Copyright (C) 2002 Authors //// +//// //// +//// This source file may be used and distributed without //// +//// restriction provided that this copyright statement is not //// +//// removed from the file and that any derivative work contains //// +//// the original copyright notice and the associated disclaimer. //// +//// //// +//// This source file is free software; you can redistribute it //// +//// and/or modify it under the terms of the GNU Lesser General //// +//// Public License as published by the Free Software Foundation; //// +//// either version 2.1 of the License, or (at your option) any //// +//// later version. //// +//// //// +//// This source is distributed in the hope that it will be //// +//// useful, but WITHOUT ANY WARRANTY; without even the implied //// +//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR //// +//// PURPOSE. See the GNU Lesser General Public License for more //// +//// details. //// +//// //// +//// You should have received a copy of the GNU Lesser General //// +//// Public License along with this source; if not, download it //// +//// from http://www.opencores.org/lgpl.shtml //// +//// //// +////////////////////////////////////////////////////////////////////// + + +`include "spi_defines.v" + +module spi_top16 + (input wb_clk_i, input wb_rst_i, + input [4:0] wb_adr_i, + input [15:0] wb_dat_i, + output reg [15:0] wb_dat_o, + input [1:0] wb_sel_i, + input wb_we_i, input wb_stb_i, input wb_cyc_i, + output reg wb_ack_o, output wb_err_o, output reg wb_int_o, + + // SPI signals + output [15:0] ss_pad_o, output sclk_pad_o, output mosi_pad_o, input miso_pad_i); + + // Internal signals + reg [15:0] divider; // Divider register + reg [`SPI_CTRL_BIT_NB-1:0] ctrl; // Control and status register + reg [15:0] ss; // Slave select register + reg [31:0] wb_dat; // wb data out + wire [31:0] rx; // Rx register + wire rx_negedge; // miso is sampled on negative edge + wire tx_negedge; // mosi is driven on negative edge + wire [`SPI_CHAR_LEN_BITS-1:0] char_len; // char len + wire go; // go + wire lsb; // lsb first on line + wire ie; // interrupt enable + wire ass; // automatic slave select + wire spi_divider_sel; // divider register select + wire spi_ctrl_sel; // ctrl register select + wire [3:0] spi_tx_sel; // tx_l register select + wire spi_ss_sel; // ss register select + wire tip; // transfer in progress + wire pos_edge; // recognize posedge of sclk + wire neg_edge; // recognize negedge of sclk + wire last_bit; // marks last character bit + + // Address decoder + assign spi_divider_sel = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_DIVIDE); + assign spi_ctrl_sel = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_CTRL); + assign spi_tx_sel[0] = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_TX_0); + assign spi_tx_sel[1] = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_TX_1); + assign spi_tx_sel[2] = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_TX_2); + assign spi_tx_sel[3] = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_TX_3); + assign spi_ss_sel = wb_cyc_i & wb_stb_i & (wb_adr_i[4:2] == `SPI_SS); + + always @(wb_adr_i or rx or ctrl or divider or ss) + case (wb_adr_i[4:2]) + `SPI_RX_0: wb_dat = rx[31:0]; + `SPI_CTRL: wb_dat = {{32-`SPI_CTRL_BIT_NB{1'b0}}, ctrl}; + `SPI_DIVIDE: wb_dat = {16'b0, divider}; + `SPI_SS: wb_dat = {16'b0, ss}; + default : wb_dat = 32'd0; + endcase // case (wb_adr_i[4:2]) + + always @(posedge wb_clk_i) + if (wb_rst_i) + wb_dat_o <= 32'b0; + else + wb_dat_o <= wb_adr_i[1] ? wb_dat[31:16] : wb_dat[15:0]; + + always @(posedge wb_clk_i) + if (wb_rst_i) + wb_ack_o <= 1'b0; + else + wb_ack_o <= wb_cyc_i & wb_stb_i & ~wb_ack_o; + + assign wb_err_o = 1'b0; + + // Interrupt + always @(posedge wb_clk_i) + if (wb_rst_i) + wb_int_o <= 1'b0; + else if (ie && tip && last_bit && pos_edge) + wb_int_o <= 1'b1; + else if (wb_ack_o) + wb_int_o <= 1'b0; + + // Divider register + always @(posedge wb_clk_i) + if (wb_rst_i) + divider <= 16'b0; + else if (spi_divider_sel && wb_we_i && !tip && ~wb_adr_i[1]) + divider <= wb_dat_i; + + // Ctrl register + always @(posedge wb_clk_i) + if (wb_rst_i) + ctrl <= {`SPI_CTRL_BIT_NB{1'b0}}; + else if(spi_ctrl_sel && wb_we_i && !tip && ~wb_adr_i[1]) + begin + if (wb_sel_i[0]) + ctrl[7:0] <= wb_dat_i[7:0] | {7'b0, ctrl[0]}; + if (wb_sel_i[1]) + ctrl[`SPI_CTRL_BIT_NB-1:8] <= wb_dat_i[`SPI_CTRL_BIT_NB-1:8]; + end + else if(tip && last_bit && pos_edge) + ctrl[`SPI_CTRL_GO] <= 1'b0; + + assign rx_negedge = ctrl[`SPI_CTRL_RX_NEGEDGE]; + assign tx_negedge = ctrl[`SPI_CTRL_TX_NEGEDGE]; + assign go = ctrl[`SPI_CTRL_GO]; + assign char_len = ctrl[`SPI_CTRL_CHAR_LEN]; + assign lsb = ctrl[`SPI_CTRL_LSB]; + assign ie = ctrl[`SPI_CTRL_IE]; + assign ass = ctrl[`SPI_CTRL_ASS]; + + // Slave select register + always @(posedge wb_clk_i) + if (wb_rst_i) + ss <= 16'b0; + else if(spi_ss_sel && wb_we_i && !tip & ~wb_adr_i[1]) + begin + if (wb_sel_i[0]) + ss[7:0] <= wb_dat_i[7:0]; + if (wb_sel_i[1]) + ss[15:8] <= wb_dat_i[15:8]; + end + + assign ss_pad_o = ~((ss & {16{tip & ass}}) | (ss & {16{!ass}})); + + spi_clgen clgen (.clk_in(wb_clk_i), .rst(wb_rst_i), .go(go), .enable(tip), .last_clk(last_bit), + .divider(divider[`SPI_DIVIDER_LEN-1:0]), .clk_out(sclk_pad_o), .pos_edge(pos_edge), + .neg_edge(neg_edge)); + + wire [3:0] new_sels = { (wb_adr_i[1] & wb_sel_i[1]), (wb_adr_i[1] & wb_sel_i[0]), + (~wb_adr_i[1] & wb_sel_i[1]), (~wb_adr_i[1] & wb_sel_i[0]) }; + + + spi_shift shift (.clk(wb_clk_i), .rst(wb_rst_i), .len(char_len[`SPI_CHAR_LEN_BITS-1:0]), + .latch(spi_tx_sel[3:0] & {4{wb_we_i}}), .byte_sel(new_sels), .lsb(lsb), + .go(go), .pos_edge(pos_edge), .neg_edge(neg_edge), + .rx_negedge(rx_negedge), .tx_negedge(tx_negedge), + .tip(tip), .last(last_bit), + .p_in({wb_dat_i,wb_dat_i}), .p_out(rx), + .s_clk(sclk_pad_o), .s_in(miso_pad_i), .s_out(mosi_pad_o)); + +endmodule // spi_top16 |