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+//
+// Copyright 2011 Ettus Research LLC
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program 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 General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+
+
+
+// Dual ported, Harvard architecture, cached ram
+
+module ram_harvard
+ #(parameter AWIDTH=15,
+ parameter RAM_SIZE=16384,
+ parameter ICWIDTH=6,
+ parameter DCWIDTH=6)
+
+ (input wb_clk_i,
+ input wb_rst_i,
+ // Firmware download port.
+ input [AWIDTH-1:0] ram_loader_adr_i,
+ input [31:0] ram_loader_dat_i,
+ input [3:0] ram_loader_sel_i,
+ input ram_loader_stb_i,
+ input ram_loader_we_i,
+ input ram_loader_done_i,
+ // Instruction fetch port.
+ input [AWIDTH-1:0] if_adr,
+ output [31:0] if_data,
+ // Data access port.
+ input [AWIDTH-1:0] dwb_adr_i,
+ input [31:0] dwb_dat_i,
+ output [31:0] dwb_dat_o,
+ input dwb_we_i,
+ output dwb_ack_o,
+ input dwb_stb_i,
+ input [3:0] dwb_sel_i );
+
+ reg ack_d1;
+ reg stb_d1;
+
+ dpram32 #(.AWIDTH(AWIDTH),.RAM_SIZE(RAM_SIZE))
+ sys_ram
+ (.clk(wb_clk_i),
+ .adr1_i(ram_loader_done_i ? if_adr : ram_loader_adr_i),
+ .dat1_i(ram_loader_dat_i),
+ .dat1_o(if_data),
+ .we1_i(ram_loader_done_i ? 1'b0 : ram_loader_we_i),
+ .en1_i(ram_loader_done_i ? 1'b1 : ram_loader_stb_i),
+ //.sel1_i(ram_loader_done_i ? 4'hF : ram_loader_sel_i),
+ .sel1_i(ram_loader_sel_i), // Sel is only for writes anyway
+ .adr2_i(dwb_adr_i),
+ .dat2_i(dwb_dat_i),
+ .dat2_o(dwb_dat_o),
+ .we2_i(dwb_we_i),
+ .en2_i(dwb_stb_i),
+ .sel2_i(dwb_sel_i)
+ );
+
+ assign dwb_ack_o = dwb_stb_i & (dwb_we_i | (stb_d1 & ~ack_d1));
+
+ always @(posedge wb_clk_i)
+ if(wb_rst_i)
+ ack_d1 <= 1'b0;
+ else
+ ack_d1 <= dwb_ack_o;
+
+ always @(posedge wb_clk_i)
+ if(wb_rst_i)
+ stb_d1 <= 0;
+ else
+ stb_d1 <= dwb_stb_i;
+
+endmodule // ram_harvard