X-Git-Url: http://git.joshuawise.com/firearm.git/blobdiff_plain/90ff449a4ff253d31572db4bf6bdabe61b6b3783..52fd78ff62b919c5dd5e59af2550e4ff733816a1:/ICache.v?ds=sidebyside diff --git a/ICache.v b/ICache.v index 43f6028..b9e4eff 100644 --- a/ICache.v +++ b/ICache.v @@ -45,6 +45,8 @@ module ICache( wire [3:0] rd_idx = rd_addr[9:6]; wire [21:0] rd_tag = rd_addr[31:10]; + reg [31:0] prev_rd_addr = 32'hFFFFFFFF; + wire cache_hit = cache_valid[rd_idx] && (cache_tags[rd_idx] == rd_tag); always @(*) begin /* XXX does this work nowadays? */ @@ -63,9 +65,13 @@ module ICache( bus_rd = 0; end - always @(posedge clk) - if (rd_req && !cache_hit) begin - if (bus_ready) begin /* Started the fill, and we have data. */ + always @(posedge clk) begin + prev_rd_addr <= {rd_addr[31:6], 6'b0}; + if (cache_fill_pos != 0 && ((prev_rd_addr != {rd_addr[31:6], 6'b0}) || cache_hit)) /* If this wasn't from the same line, or we've moved on somehow, reset the fill circuitry. */ + cache_fill_pos <= 0; + else if (rd_req && !cache_hit) begin + if (bus_ack && bus_ready) begin /* Started the fill, and we have data. */ + $display("ICACHE: FILL: rd addr %08x; bus addr %08x; bus data %08x", rd_addr, bus_addr, bus_rdata); cache_data[rd_idx][cache_fill_pos] <= bus_rdata; cache_fill_pos <= cache_fill_pos + 1; if (cache_fill_pos == 15) begin /* Done? */ @@ -74,4 +80,5 @@ module ICache( end end end + end endmodule