first cut at making a bidirectional 2 port ram for the gpmc data interface

ISE chokes on the unequal size ram

3 files changed, 63 insertions, 6 deletions

diff --git a/usrp2/control_lib/ram_2port_mixed_width.v b/usrp2/control_lib/ram_2port_mixed_width.v
new file mode 100644
index 000000000..3fa43114f
--- /dev/null
+++ b/usrp2/control_lib/ram_2port_mixed_width.v
@@ -0,0 +1,44 @@
+
+
+module ram_2port_mixed_width
+  #(parameter AWIDTH=9)
+    (input clk16,
+     input en16,
+     input we16,
+     input [10:0] addr16,
+     input [15:0] di16,
+     output reg [15:0] do16,
+     
+     input clk32,
+     input en32,
+     input we32,
+     input [9:0] addr32,
+     input [31:0] di32,
+     output reg [31:0] do32);
+   
+   reg [31:0] 	       ram [(1<<AWIDTH)-1:0];
+   integer 	       i;
+   initial
+     for(i=0;i<512;i=i+1)
+       ram[i] <= 32'b0;
+   
+   always @(posedge clk16)
+     if (en16)
+       begin
+          if (we16)
+            if(addr16[0])
+	      ram[addr16[10:1]][15:0] <= di16;
+	    else
+	      ram[addr16[10:1]][31:16] <= di16;
+	  do16 <= addr16[0] ? ram[addr16[10:1]][15:0] : ram[addr16[10:1]][31:16];
+       end
+
+   always @(posedge clk32)
+     if (en32)
+       begin
+          if (we32)
+            ram[addr32] <= di32;
+          do32 <= ram[addr32];
+       end
+
+endmodule // ram_2port_mixed_width
diff --git a/usrp2/gpmc/gpmc.v b/usrp2/gpmc/gpmc.v
index 56f879abc..88f6809f8 100644
--- a/usrp2/gpmc/gpmc.v
+++ b/usrp2/gpmc/gpmc.v
@@ -2,12 +2,19 @@
 //////////////////////////////////////////////////////////////////////////////////
 
 module gpmc
-  (input EM_CLK, inout [15:0] EM_D, input [10:1] EM_A, input [1:0] EM_NBE,
+  (// GPMC signals
+   input EM_CLK, inout [15:0] EM_D, input [10:1] EM_A, input [1:0] EM_NBE,
    input EM_WAIT0, input EM_NCS4, input EM_NCS6, input EM_NWE, input EM_NOE,
 
+   // Wishbone signals
    input wb_clk, input wb_rst,
    output reg [10:0] wb_adr_o, output reg [15:0] wb_dat_mosi, input [15:0] wb_dat_miso,
-   output reg [1:0] wb_sel_o, output wb_cyc_o, output reg wb_stb_o, output reg wb_we_o, input wb_ack_i
+   output reg [1:0] wb_sel_o, output wb_cyc_o, output reg wb_stb_o, output reg wb_we_o, input wb_ack_i,
+
+   // RAM Interface signals
+   input ram_clk, 
+   input read_en, input read_sel, input [8:0] read_addr, output [31:0] read_data, output read_rdy,
+   input write_en, input write_sel, input [8:0] write_addr, input [31:0] write_data, output write_rdy
    );
 
    wire 	EM_output_enable = (~EM_NOE & (~EM_NCS4 | ~EM_NCS6));
@@ -17,9 +24,15 @@ module gpmc
    assign EM_D = ~EM_output_enable ? 16'bz : ~EM_NCS4 ? EM_D_ram : EM_D_wb;
 
    // CS4 is RAM_2PORT for high-speed data
-   ram_2port #(.DWIDTH(16), .AWIDTH(10)) ram_2port
-     (.clka(wb_clk), .ena(~EM_NCS4), .wea(~EM_NWE), .addra(EM_A), .dia(EM_D), .doa(EM_D_ram),
-      .clkb(wb_clk), .enb(0), .web(0), .addrb(0), .dib(0), .dob());
+   // Writes go into one RAM, reads come from the other
+   
+   ram_2port_mixed_width buffer_from_host
+     (.clk16(wb_clk), .en16(~EM_NCS4), .we16(~EM_NWE), .addr16({store_pg,EM_A}), .di16(EM_D), .do16(),
+      .clk32(ram_clk), .en32(read_en), .we32(0), .addr32({read_sel,read_addr}), .di32(0), .do32(read_data));
+
+   ram_2port_mixed_width buffer_to_host
+     (.clk16(wb_clk), .en16(~EM_NCS4), .we16(0), .addr16({retr_page,EM_A}), .di16(0), .do16(EM_D_ram),
+      .clk32(ram_clk), .en32(write_en), .we32(write_en), .addr32({write_sel,write_addr}), .di32(write_data), .do32());
 
    // CS6 is Control, Wishbone bus bridge (wb master)
    // Sync version
@@ -51,7 +64,6 @@ module gpmc
 
    assign EM_D_wb = wb_ack_i ? wb_dat_miso : EM_D_wb_reg;
    
-   // stb, oe_del, we_del
    assign wb_cyc_o = wb_stb_o;
 
    always @(posedge wb_clk)
diff --git a/usrp2/top/u1e/Makefile b/usrp2/top/u1e/Makefile
index bcd80df6a..306ab5bae 100644
--- a/usrp2/top/u1e/Makefile
+++ b/usrp2/top/u1e/Makefile
@@ -66,6 +66,7 @@ control_lib/mux4.v \
 control_lib/mux8.v \
 control_lib/nsgpio16LE.v \
 control_lib/ram_2port.v \
+control_lib/ram_2port_mixed_width.v \
 control_lib/ram_harv_cache.v \
 control_lib/ram_loader.v \
 control_lib/setting_reg.v \