diff options
Diffstat (limited to 'rtl/gfx/gfx_sp_widener.sv')
| -rw-r--r-- | rtl/gfx/gfx_sp_widener.sv | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/rtl/gfx/gfx_sp_widener.sv b/rtl/gfx/gfx_sp_widener.sv new file mode 100644 index 0000000..92101ca --- /dev/null +++ b/rtl/gfx/gfx_sp_widener.sv @@ -0,0 +1,63 @@ +`include "gfx/gfx_defs.sv" + +module gfx_sp_widener +#(parameter WIDTH=0) // Quartus no soporta 'parameter type' +( + input logic clk, + rst_n, + + input logic word_waitrequest, + word_readdatavalid, + input vram_word word_readdata, + output vram_addr word_address, + output logic word_read, + + input logic wide_read, + input logic[WIDTH - 1:0] wide_address, + output logic wide_waitrequest, + wide_readdatavalid, + + output logic[DATA_WIDTH - 1:0] wide_readdata +); + + // Este módulo existe para fingir que la DE1-SoC tiene un bus de SDRAM más ancho + + localparam WIDE_BITS = $bits(vram_addr) - WIDTH, + WIDE_SIZE = 1 << WIDE_BITS, + DATA_WIDTH = $bits(vram_word) << WIDE_BITS; + + vram_word shift_in[WIDE_SIZE]; + logic[WIDE_BITS - 1:0] address_count, read_count; + + assign word_read = wide_read; + assign word_address = {wide_address, address_count}; + assign wide_waitrequest = word_waitrequest || !(&address_count); + + always_comb + for (integer i = 0; i < WIDE_SIZE; ++i) + wide_readdata[$bits(vram_word) * i +: $bits(vram_word)] = shift_in[i]; + + always_ff @(posedge clk or negedge rst_n) + if (!rst_n) begin + read_count <= 0; + address_count <= 0; + wide_readdatavalid <= 0; + end else begin + if (word_read && !word_waitrequest) + address_count <= address_count + 1; + + if (word_readdatavalid) + read_count <= read_count + 1; + + wide_readdatavalid <= word_readdatavalid && &read_count; + end + + always_ff @(posedge clk) + if (word_readdatavalid) begin + for (integer i = 0; i < WIDE_SIZE - 1; ++i) + shift_in[i] <= shift_in[i + 1]; + + shift_in[WIDE_SIZE - 1] <= word_readdata; + end + +endmodule |
