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-rw-r--r--fpga/usrp2/extramfifo/fifo_extram.v188
1 files changed, 0 insertions, 188 deletions
diff --git a/fpga/usrp2/extramfifo/fifo_extram.v b/fpga/usrp2/extramfifo/fifo_extram.v
deleted file mode 100644
index 4e1f40371..000000000
--- a/fpga/usrp2/extramfifo/fifo_extram.v
+++ /dev/null
@@ -1,188 +0,0 @@
-
-// Everything on sram_clk
-
-module fifo_extram
- (input reset, input clear,
- input [17:0] datain, input src_rdy_i, output dst_rdy_o, output [15:0] space, input [15:0] occ_in,
- output [17:0] dataout, output src_rdy_o, input dst_rdy_i, output [15:0] occupied, input [15:0] space_in,
- input sram_clk, output [18:0] sram_a, inout [17:0] sram_d, output sram_we,
- output [1:0] sram_bw, output sram_adv, output sram_ce, output sram_oe,
- output sram_mode, output sram_zz);
-
- localparam AWIDTH = 19; // 1 MB in x18
- localparam RAMSIZE = ((1<<AWIDTH) - 1);
-
- wire do_store, do_retrieve;
- reg [1:0] do_store_del, do_retr_del;
-
- reg [AWIDTH-1:0] addr_retrieve, addr_store;
- always @(posedge sram_clk)
- if(reset | clear)
- addr_retrieve <= 0;
- else if (do_retrieve)
- addr_retrieve <= addr_retrieve + 1;
-
- always @(posedge sram_clk)
- if(reset | clear)
- addr_store <= 0;
- else if(do_store)
- addr_store <= addr_store + 1;
-
- //wire [AWIDTH-1:0] fullness = (addr_store - addr_retrieve);
- reg [AWIDTH-1:0] fullness;
- always @(posedge sram_clk)
- if(reset | clear)
- fullness <= 0;
- else if(do_store)
- fullness <= fullness + 1;
- else if(do_retrieve)
- fullness <= fullness - 1;
-
- // wire empty = (fullness == 0);
- //wire full = (fullness == RAMSIZE); // 19'h7FF);
- reg empty, full;
-
- // The math in the following functions is 'AWIDTH wide. Use
- // continuous assignments to prevent the numbers from being
- // promoted to 32-bit (which would make it wrap wrong).
- //
- wire [AWIDTH-1:0] addr_retrieve_p1, addr_store_p2;
- assign addr_retrieve_p1 = addr_retrieve + 1;
- assign addr_store_p2 = addr_store + 2;
-
- always @(posedge sram_clk)
- if(reset | clear)
- empty <= 1;
- else if(do_store)
- empty <= 0;
- else if(do_retrieve & (/*(addr_retrieve + 1)*/ addr_retrieve_p1 == addr_store))
- empty <= 1;
-
- always @(posedge sram_clk)
- if(reset | clear)
- full <= 0;
- else if(do_retrieve)
- full <= 0;
- else if(do_store & (/*(addr_store+2)*/ addr_store_p2 == addr_retrieve))
- full <= 1;
-
- reg can_store;
- always @*
- if(full | ~src_rdy_i)
- can_store <= 0;
- else if(do_store_del == 0)
- can_store <= 1;
- else if((do_store_del == 1) || (do_store_del == 2))
- can_store <= (occ_in > 1);
- else
- can_store <= (occ_in > 2);
-
- reg can_retrieve;
- always @*
- if(empty | ~dst_rdy_i)
- can_retrieve <= 0;
- else if(do_retr_del == 0)
- can_retrieve <= 1;
- else if((do_retr_del == 1) || (do_retr_del == 2))
- can_retrieve <= (space_in > 1);
- else
- can_retrieve <= (space_in > 2);
-
- reg [1:0] state;
- localparam IDLE_STORE_NEXT = 0;
- localparam STORE = 1;
- localparam IDLE_RETR_NEXT = 2;
- localparam RETRIEVE = 3;
-
- reg [7:0] countdown;
- wire countdown_done = (countdown == 0);
-
- localparam CYCLE_SIZE = 6;
-
- assign do_store = can_store & (state == STORE);
- assign do_retrieve = can_retrieve & (state == RETRIEVE);
- always @(posedge sram_clk)
- if(reset)
- do_store_del <= 0;
- else
- do_store_del <= {do_store_del[0],do_store};
-
- always @(posedge sram_clk)
- if(reset)
- do_retr_del <= 0;
- else
- do_retr_del <= {do_retr_del[0],do_retrieve};
-
- always @(posedge sram_clk)
- if(reset | clear)
- begin
- state <= IDLE_STORE_NEXT;
- countdown <= 0;
- end
- else
- case(state)
- IDLE_STORE_NEXT :
- if(can_store)
- begin
- state <= STORE;
- countdown <= CYCLE_SIZE;
- end
- else if(can_retrieve)
- begin
- state <= RETRIEVE;
- countdown <= CYCLE_SIZE;
- end
- STORE :
- if(~can_store | (can_retrieve & countdown_done))
- state <= IDLE_RETR_NEXT;
- else if(~countdown_done)
- countdown <= countdown - 1;
- IDLE_RETR_NEXT :
- if(can_retrieve)
- begin
- state <= RETRIEVE;
- countdown <= CYCLE_SIZE;
- end
- else if(can_store)
- begin
- state <= STORE;
- countdown <= CYCLE_SIZE;
- end
- RETRIEVE :
- if(~can_retrieve | (can_store & countdown_done))
- state <= IDLE_STORE_NEXT;
- else if(~countdown_done)
- countdown <= countdown - 1;
- endcase // case (state)
-
- // RAM wires
- assign sram_bw = 0;
- assign sram_adv = 0;
- assign sram_mode = 0;
- assign sram_zz = 0;
- assign sram_ce = 0;
-
- assign sram_a = (state==STORE) ? addr_store : addr_retrieve;
- assign sram_we = ~do_store;
- assign sram_oe = ~do_retr_del[1];
- assign my_oe = do_store_del[1] & sram_oe;
- assign sram_d = my_oe ? datain : 18'bz;
-
- // FIFO wires
- assign dataout = sram_d;
- assign src_rdy_o = do_retr_del[1];
- assign dst_rdy_o = do_store_del[1];
-
-endmodule // fifo_extram
-
-
- //wire have_1 = (fullness == 1);
- //wire have_2 = (fullness == 2);
- //wire have_atleast_1 = ~empty;
- //wire have_atleast_2 = ~(empty | have_1);
- //wire have_atleast_3 = ~(empty | have_1 | have_2);
- //wire full_minus_1 = (fullness == (RAMSIZE-1)); // 19'h7FE);
- //wire full_minus_2 = (fullness == (RAMSIZE-2)); // 19'h7FD);
- //wire spacefor_atleast_1 = ~full;
- //wire spacefor_atleast_2 = ~(full | full_minus_1);
- //wire spacefor_atleast_3 = ~(full | full_minus_1 | full_minus_2);