Merge branch 'master' into mwest/b200_docs

1 files changed, 95 insertions, 0 deletions

diff --git a/fpga/usrp3/lib/zynq_fifo/zf_slave_settings.v b/fpga/usrp3/lib/zynq_fifo/zf_slave_settings.v
new file mode 100644
index 000000000..026845682
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+++ b/fpga/usrp3/lib/zynq_fifo/zf_slave_settings.v
@@ -0,0 +1,95 @@
+//////////////////////////////////////////////////////////////////////////////////
+// Copyright Ettus Research LLC
+// The ZYNQ FIFO slave settings:
+//  - implements write state machine for 32-bit addressable AXI slave
+//  - provides settings for state of per-stream fifo pointers
+//  - implements configuration of FIFO's physical DDR addresses
+//////////////////////////////////////////////////////////////////////////////////
+
+
+module zf_slave_settings
+#(
+    parameter CONFIG_BASE = 32'h40000000
+)
+(
+    input clk,
+    input rst,
+
+    //------------------------------------------------------------------
+    //-- control write signals - slave
+    //------------------------------------------------------------------
+    input [31:0] AXI_AWADDR,
+    input AXI_AWVALID,
+    output AXI_AWREADY,
+    input [31:0] AXI_WDATA,
+    input [3:0] AXI_WSTRB,
+    input AXI_WVALID,
+    output AXI_WREADY,
+    output [1:0] AXI_BRESP,
+    output AXI_BVALID,
+    input AXI_BREADY,
+
+    //------------------------------------------------------------------
+    // settings interface
+    //------------------------------------------------------------------
+    output reg [31:0] addr,
+    output reg [31:0] data,
+    output strobe,
+
+    output [31:0] debug
+);
+
+////////////////////////////////////////////////////////////////////////
+///////////////////////////// Begin R T L //////////////////////////////
+////////////////////////////////////////////////////////////////////////
+
+    //------------------------------------------------------------------
+    // Control write state machine responds to AXI control writes
+    // Used for setting the state of the various FIFOs
+    //------------------------------------------------------------------
+    localparam STATE_ADDR = 0;
+    localparam STATE_DATA = 1;
+    localparam STATE_WRITE = 2;
+
+    reg [1:0] state;
+
+    always @(posedge clk) begin
+        if (rst) begin
+            state <= STATE_ADDR;
+            addr <= 0;
+            data <= 0;
+        end
+        else case (state)
+
+        STATE_ADDR: begin
+            if (AXI_AWVALID && AXI_AWREADY) begin
+                addr <= (AXI_AWADDR - CONFIG_BASE);
+                state <= STATE_DATA;
+            end
+        end
+
+        STATE_DATA: begin
+            if (AXI_WVALID && AXI_WREADY) begin
+                data <= AXI_WDATA;
+                state <= STATE_WRITE;
+            end
+        end
+
+        STATE_WRITE: begin
+            state <= STATE_ADDR;
+        end
+
+        default: state <= STATE_ADDR;
+
+        endcase //state
+    end
+
+    assign strobe = (state == STATE_WRITE);
+
+    //assign to slave write
+    assign AXI_AWREADY = (state == STATE_ADDR);
+    assign AXI_WREADY = (state == STATE_DATA);
+    assign AXI_BRESP = 0;
+    assign AXI_BVALID = AXI_BREADY; //FIXME - we can choose not to assert valid
+
+endmodule //zf_slave_settings