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-rw-r--r--control_lib/dcache.v165
1 files changed, 0 insertions, 165 deletions
diff --git a/control_lib/dcache.v b/control_lib/dcache.v
deleted file mode 100644
index 9063bf02a..000000000
--- a/control_lib/dcache.v
+++ /dev/null
@@ -1,165 +0,0 @@
-
-module dcache
- #(parameter AWIDTH=14,
- parameter CWIDTH=6)
- (input wb_clk_i,
- input wb_rst_i,
-
- input [AWIDTH-1:0] dwb_adr_i,
- input dwb_stb_i,
- input dwb_we_i,
- input [3:0] dwb_sel_i,
- input [31:0] dwb_dat_i,
- output [31:0] dwb_dat_o,
- output dwb_ack_o,
-
- input [31:0] dram_dat_i,
- output [31:0] dram_dat_o,
- output [AWIDTH-1:0] dram_adr_o,
- output dram_we_o,
- output dram_en_o,
- output [3:0] dram_sel_o );
-
- localparam TAGWIDTH = AWIDTH-CWIDTH-2;
- reg stb_d1, ack_d1, miss_d1;
- reg [AWIDTH-1:0] held_addr;
- reg [31:0] ddata [0:(1<<CWIDTH)-1];
- reg [TAGWIDTH-1:0] dtags [0:(1<<CWIDTH)-1];
- reg dvalid [0:(1<<CWIDTH)-1];
-
- wire [CWIDTH-1:0] rd_line, wr_line;
- wire [TAGWIDTH-1:0] wr_tags;
- wire cache_write, invalidate;
- wire [31:0] wr_data;
-
- // /////////////////////////////////////
- // Write into cache
- integer i;
- always @(posedge wb_clk_i)
- if(wb_rst_i)
- for(i=0;i<(1<<CWIDTH);i=i+1)
- dvalid[i] <= 0;
- else
- if(invalidate)
- dvalid[wr_line] <= 1'b0;
- else if(cache_write)
- dvalid[wr_line] <= 1'b1;
-
- always @(posedge wb_clk_i)
- if(cache_write)
- begin
- ddata[wr_line] <= wr_data;
- dtags[wr_line] <= wr_tags;
- end
-
- // //////////////////////////////////////
- // Read from Cache
- wire [TAGWIDTH-1:0] tag_out = dtags[rd_line];
- wire valid_out = dvalid[rd_line];
- wire [31:0] data_out = ddata[rd_line];
- wire cache_hit = valid_out & (tag_out == dwb_adr_i[AWIDTH-1:CWIDTH+2]);
- wire cache_miss = ~cache_hit;
-
- // //////////////////////////////////////
- // Handle 1-cycle delay of Block-RAM
- always @(posedge wb_clk_i)
- if(wb_rst_i)
- stb_d1 <= 0;
- else
- stb_d1 <= dwb_stb_i;
-
- always @(posedge wb_clk_i)
- if(wb_rst_i)
- held_addr <= 0;
- else
- held_addr <= dwb_adr_i;
-
- 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)
- miss_d1 <= 0;
- else
- miss_d1 <= cache_miss;
-
-`define DC_NOCACHE
-//`define DC_BASIC
-//`define DC_FORWARDING_DP
-//`define DC_FORWARDING_SP
-//`define DC_PREFETCH
-
-`ifdef DC_NOCACHE
- assign dwb_dat_o = dram_dat_i;
- assign dwb_ack_o = dwb_stb_i & (dwb_we_i | (stb_d1 & ~ack_d1));
- assign dram_adr_o = dwb_adr_i;
- assign dram_en_o = dwb_stb_i;
- assign dram_dat_o = dwb_dat_i;
- assign dram_we_o = dwb_we_i;
- assign dram_sel_o = dwb_sel_i;
- assign rd_line = 0;
- assign wr_line = 0;
- assign wr_tags = 0;
- assign wr_data = 0;
- assign cache_write = 0;
- assign invalidate = 0;
-`endif
-
-`ifdef DC_BASIC // Very basic, no forwarding, 2 wait states on miss
- assign dwb_dat_o = data_out;
- assign dwb_ack_o = dwb_stb_i & cache_hit;
- assign dram_adr_o = dwb_adr_i;
- assign dram_en_o = dwb_stb_i;
- assign dram_dat_o = dwb_dat_i;
- assign dram_we_o = dwb_we_i;
- assign dram_sel_o = dwb_sel_i;
- assign rd_line = dwb_adr_i[CWIDTH+1:2];
- assign wr_line = rd_line;
- assign wr_tags = dwb_adr_i[AWIDTH-1:CWIDTH+2];
- assign wr_data = dwb_we_i ? dwb_dat_i : dram_dat_i;
- assign cache_write = dwb_stb_i & (dwb_we_i | (stb_d1 & miss_d1));
- assign invalidate = dwb_we_i & ~(&dwb_sel_i);
-`endif
-
-`ifdef DC_FORWARDING_DP // Simple forwarding, 1 wait state on miss, dual-port ram
- assign dwb_dat_o = cache_hit ? data_out : dram_dat_i;
- assign dwb_ack_o = dwb_stb_i & (cache_hit | (stb_d1 & ~ack_d1));
- assign dram_adr_o = dwb_adr_i;
- assign dram_en_o = 1'b1;
- assign dram_dat_o = dwb_dat_i;
- assign dram_we_o = dwb_we_i;
- assign dram_sel_o = dwb_sel_i;
- assign rd_line = dwb_adr_i[CWIDTH+1:2];
- assign wr_line = held_addr[CWIDTH+1:2];
- assign wr_tags = held_addr[AWIDTH-1:CWIDTH+2];
- assign wr_data = dram_dat_i;
- assign cache_write = dwb_stb_i & stb_d1 & miss_d1 & ~ack_d1;
- assign invalidate = 0;
-`endif
-
-`ifdef DC_FORWARDING_SP // Simple forwarding, 1 wait state on miss, single-port ram
- assign dwb_dat_o = cache_hit ? data_out : dram_dat_i;
- assign dwb_ack_o = dwb_stb_i & (cache_hit | (stb_d1 & ~ack_d1));
- assign dram_adr_o = dwb_adr_i;
- assign dram_en_o = 1'b1;
- assign dram_dat_o = dwb_dat_i;
- assign dram_we_o = dwb_we_i;
- assign dram_sel_o = dwb_sel_i;
- assign rd_line = dwb_adr_i[CWIDTH+1:2];
- assign wr_line = rd_line;
- assign wr_tags = dwb_adr_i[AWIDTH-1:CWIDTH+2];
- assign wr_data = dram_dat_i;
- assign cache_write = dwb_stb_i & stb_d1 & miss_d1 & ~ack_d1;
- assign invalidate = 0;
-`endif
-
-`ifdef DC_PREFETCH // Forwarding plus prefetch
-
-`endif
-
-
-endmodule // dcache
-