1 files changed, 103 insertions, 0 deletions
diff --git a/fpga/usrp2/control_lib/ram_wb_harvard.v b/fpga/usrp2/control_lib/ram_wb_harvard.v
new file mode 100644
index 000000000..8d5a45247
--- /dev/null
+++ b/fpga/usrp2/control_lib/ram_wb_harvard.v
@@ -0,0 +1,103 @@
+//
+// 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 RAM for Harvard architecture processors
+//    Does no forwarding
+//    Addresses are byte-oriented, so botton 2 address bits are ignored.  FIXME
+//    AWIDTH of 13 gives 8K bytes.  For Spartan 3, if the total RAM size is not a
+//    multiple of 8K then BRAM space is wasted
+
+module ram_wb_harvard #(parameter AWIDTH=13)
+  (input wb_clk_i,
+   input wb_rst_i,
+   
+   input [AWIDTH-1:0] iwb_adr_i,
+   input [31:0] iwb_dat_i,
+   output reg [31:0] iwb_dat_o,
+   input iwb_we_i,
+   output reg iwb_ack_o,
+   input iwb_stb_i,
+   input [3:0] iwb_sel_i,
+   
+   input [AWIDTH-1:0] dwb_adr_i,
+   input [31:0] dwb_dat_i,
+   output reg [31:0] dwb_dat_o,
+   input dwb_we_i,
+   output reg dwb_ack_o,
+   input dwb_stb_i,
+   input [3:0] dwb_sel_i);
+   
+   reg [7:0] 	 ram0 [0:(1<<(AWIDTH-2))-1];
+   reg [7:0] 	 ram1 [0:(1<<(AWIDTH-2))-1];
+   reg [7:0] 	 ram2 [0:(1<<(AWIDTH-2))-1];
+   reg [7:0] 	 ram3 [0:(1<<(AWIDTH-2))-1];
+   
+   // Instruction Read Port
+   always @(posedge wb_clk_i)
+     iwb_ack_o <= iwb_stb_i & ~iwb_ack_o;
+   
+   always @(posedge wb_clk_i)
+     iwb_dat_o[31:24] <= ram3[iwb_adr_i[AWIDTH-1:2]];
+   always @(posedge wb_clk_i)
+     iwb_dat_o[23:16] <= ram2[iwb_adr_i[AWIDTH-1:2]];
+   always @(posedge wb_clk_i)
+     iwb_dat_o[15:8] <= ram1[iwb_adr_i[AWIDTH-1:2]];
+   always @(posedge wb_clk_i)
+     iwb_dat_o[7:0] <= ram0[iwb_adr_i[AWIDTH-1:2]];
+   
+   always @(posedge wb_clk_i)
+     if(iwb_we_i & iwb_stb_i & iwb_sel_i[3])
+       ram3[iwb_adr_i[AWIDTH-1:2]] <= iwb_dat_i[31:24];
+   always @(posedge wb_clk_i)
+     if(iwb_we_i & iwb_stb_i & iwb_sel_i[2])
+       ram2[iwb_adr_i[AWIDTH-1:2]] <= iwb_dat_i[23:16];
+   always @(posedge wb_clk_i)
+     if(iwb_we_i & iwb_stb_i & iwb_sel_i[1])
+       ram1[iwb_adr_i[AWIDTH-1:2]] <= iwb_dat_i[15:8];
+   always @(posedge wb_clk_i)
+     if(iwb_we_i & iwb_stb_i & iwb_sel_i[0])
+       ram0[iwb_adr_i[AWIDTH-1:2]] <= iwb_dat_i[7:0];
+   
+   // Data Port
+   always @(posedge wb_clk_i)
+     dwb_ack_o <= dwb_stb_i & ~dwb_ack_o;
+   
+   always @(posedge wb_clk_i)
+     dwb_dat_o[31:24] <= ram3[dwb_adr_i[AWIDTH-1:2]];
+   always @(posedge wb_clk_i)
+     dwb_dat_o[23:16] <= ram2[dwb_adr_i[AWIDTH-1:2]];
+   always @(posedge wb_clk_i)
+     dwb_dat_o[15:8] <= ram1[dwb_adr_i[AWIDTH-1:2]];
+   always @(posedge wb_clk_i)
+     dwb_dat_o[7:0]  <= ram0[dwb_adr_i[AWIDTH-1:2]];
+   
+   always @(posedge wb_clk_i)
+     if(dwb_we_i & dwb_stb_i & dwb_sel_i[3])
+       ram3[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[31:24];
+   always @(posedge wb_clk_i)
+     if(dwb_we_i & dwb_stb_i & dwb_sel_i[2])
+       ram2[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[23:16];
+   always @(posedge wb_clk_i)
+     if(dwb_we_i & dwb_stb_i & dwb_sel_i[1])
+       ram1[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[15:8];
+   always @(posedge wb_clk_i)
+     if(dwb_we_i & dwb_stb_i & dwb_sel_i[0])
+       ram0[dwb_adr_i[AWIDTH-1:2]] <= dwb_dat_i[7:0];
+   
+endmodule // ram_wb_harvard
+