// Copyright 2021 Alexey Melnikov // Copyright 2026 (CD32 native-mode register/IRQ extensions) // // This file is part of Minimig // // Minimig is free software; you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation; either version 3 of the License, or // (at your option) any later version. // // Minimig is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License for more details. // // You should have received a copy of the GNU General Public License // along with this program. If not, see . // //---------------------------------------------------------------------------------- module akiko #(parameter NATIVE_CD32 = 0) ( input clk, input reset, input cs, input rd, input wr, input lds, input uds, input [5:1] addr, input [15:0] din, output reg [15:0] dout, output akiko_irq, output dma_req, output dma_we, output [23:0] dma_baddr, output [7:0] dma_wbyte, input [7:0] dma_rbyte, input dma_ack, input dma_arm, output hps_cmd_pending, output [7:0] hps_cmd_byte, input hps_cmd_pop, input hps_cmd_done, input hps_result_push, input [7:0] hps_result_byte, input hps_result_done, output hps_sec_req, output [7:0] hps_sec_status, input hps_sec_push, input [15:0] hps_sec_word, input hps_sec_done, output hps_rx_busy, input [9:0] hps_nvr_addr, output [7:0] hps_nvr_dout, input hps_nvr_clear_dirty, output hps_nvr_dirty, input [9:0] nvr_load_addr, input [7:0] nvr_load_din, input nvr_load_we, input hps_subcode_push, input [7:0] hps_subcode_byte, input hps_subcode_done ); localparam [31:0] INTENA_MASK = 32'hff000000; localparam [31:0] CONFIG_MASK = 32'hff800000; localparam [31:0] ADDRDATA_MASK = 32'h00fff000; localparam [31:0] ADDRMISC_MASK = 32'h00fffc00; localparam [31:0] CDINT_SUBCODE = 32'h80000000; localparam [31:0] CDINT_DRIVEXMIT = 32'h40000000; localparam [31:0] CDINT_DRIVERECV = 32'h20000000; localparam [31:0] CDINT_RXDMADONE = 32'h10000000; localparam [31:0] CDINT_TXDMADONE = 32'h08000000; localparam [31:0] CDINT_PBX = 32'h04000000; localparam [31:0] CDINT_OVERFLOW = 32'h02000000; localparam CDFLAG_TXD_BIT = 30; localparam CDFLAG_RXD_BIT = 29; localparam CDFLAG_PBX_BIT = 27; localparam CDFLAG_ENABLE_BIT = 26; wire c2p_sel = (addr[5:2] == 'b1110); reg [7:0] buff[32]; reg [3:0] rptr = 0, wptr = 0; always @(posedge clk) begin if((wr|rd) & cs & c2p_sel) begin if (wr) begin rptr <= 0; wptr <= wptr + 1'd1; {buff[{wptr,1'b0}],buff[{wptr,1'b1}]} <= din; end else begin wptr <= 0; rptr <= rptr + 1'd1; end end end reg [15:0] c2p_dout; always @(*) begin : c2p_read reg [4:0] i; c2p_dout = 16'h0; for (i=0; i<16; i=i+1'd1) c2p_dout[i] = buff[{rptr[0],~i[3:0]}][rptr[3:1]]; end wire [15:0] cd_dout; wire cd_irq; wire cd_dma_req; wire cd_dma_we; wire [23:0] cd_dma_baddr; wire [7:0] cd_dma_wbyte; wire cd_hps_cmd_pending; wire [7:0] cd_hps_cmd_byte; wire cd_hps_sec_req; wire [7:0] cd_hps_sec_status; wire cd_hps_rx_busy; wire [7:0] cd_hps_nvr_dout; wire cd_hps_nvr_dirty; generate if (NATIVE_CD32) begin : g_cd reg [31:0] cdrom_intreq; reg [31:0] cdrom_intena; reg [31:0] cdrom_addressdata; reg [31:0] cdrom_addressmisc; reg [31:0] cdrom_flags; reg [15:0] cdrom_pbx; reg [7:0] cdrom_subcodeoffset; reg [7:0] cdcomtxinx; reg [7:0] cdcomrxinx; reg [7:0] cdcomtxcmp; reg [7:0] cdcomrxcmp; reg [7:0] pio_byte; reg [7:0] nvram_io; reg [7:0] nvram_dir; // wire nvram_scl_master_drive = nvram_dir[7]; wire nvram_sda_master_drive = nvram_dir[6]; wire nvram_scl_bus = nvram_scl_master_drive ? nvram_io[7] : 1'b1; wire nvram_sda_master_value = nvram_sda_master_drive ? nvram_io[6] : 1'b1; wire nvram_slave_sda_drive; wire nvram_sda_bus = nvram_sda_master_value & ~nvram_slave_sda_drive; reg [7:0] cdrom_command_buffer [32]; reg [5:0] cdrom_command_length; reg [7:0] cdrom_result_buffer [32]; reg [5:0] cdrom_receive_length; reg [5:0] cdrom_receive_offset; reg [1:0] tx_dma_delay; reg [1:0] rx_dma_delay; reg tx_busy; reg rx_busy; reg rx_inflight; reg pio_wr_d; reg pio_rd_d; localparam [1:0] OWN_RX = 2'd0, OWN_PBX = 2'd1, OWN_TX = 2'd2, OWN_SUB = 2'd3; reg dma_owned; reg [1:0] dma_owner; wire own_rx = dma_owned & (dma_owner == OWN_RX); wire own_pbx = dma_owned & (dma_owner == OWN_PBX); wire own_tx = dma_owned & (dma_owner == OWN_TX); wire own_sub = dma_owned & (dma_owner == OWN_SUB); reg [5:0] hps_cmd_rd_ptr; reg [5:0] hps_result_wr_ptr; // // reg [15:0] sector_buffer [1176]; reg [10:0] sec_wr_ptr; reg sector_ready; wire sec_w_we = hps_sec_push && sec_wr_ptr != 11'd1176; wire [10:0] sec_w_addr = sec_wr_ptr; wire [15:0] sec_w_din = hps_sec_word; reg [7:0] cdrom_sector_counter; reg pbx_busy; reg [1:0] pbx_state; localparam PBX_IDLE = 2'd0; localparam PBX_DATA = 2'd1; localparam PBX_ZERO = 2'd2; localparam PBX_FIN = 2'd3; reg [3:0] pbx_seccnt; reg [11:0] pbx_byte_idx; reg pbx_ship_invalid; reg [7:0] subbuf [96]; reg [6:0] sub_wr_ptr; reg subcode_ready; reg subcode_busy; reg subcode_irq; reg [1:0] subcode_state; localparam SUB_IDLE = 2'd0; localparam SUB_DATA = 2'd1; localparam SUB_FIN = 2'd2; localparam CDFLAG_SUBCODE_BIT = 31; reg [7:0] subcode_off; reg [7:0] sub_idx; function [5:0] expected_total_len; input [3:0] op; case (op) 4'h0: expected_total_len = 6'd2; 4'h1: expected_total_len = 6'd3; 4'h2: expected_total_len = 6'd2; 4'h3: expected_total_len = 6'd2; 4'h4: expected_total_len = 6'd13; 4'h5: expected_total_len = 6'd3; 4'h6: expected_total_len = 6'd2; 4'h7: expected_total_len = 6'd2; 4'h8: expected_total_len = 6'd5; 4'h9: expected_total_len = 6'd2; 4'ha: expected_total_len = 6'd3; default: expected_total_len = 6'd32; endcase endfunction wire [3:0] cmd_op = cdrom_command_buffer[0][3:0]; wire [7:0] cmd_arg1 = cdrom_command_buffer[1]; wire [5:0] cmd_total = expected_total_len(cmd_op); wire cmd_zero_result = ((cmd_op == 4'h5) && !cmd_arg1[7]) || (cmd_op == 4'h8) || (cmd_op == 4'h9) || (cmd_op == 4'ha); wire cmd_pending = (cdrom_command_length != 6'd0) && ((cdrom_command_length >= cmd_total) || (cdrom_command_length == 6'd32)); wire [23:0] cdrx_address = cdrom_addressmisc[23:0]; wire [23:0] cdtx_address = cdrom_addressmisc[23:0] | 24'h000200; wire [23:0] subcode_address = cdrom_addressmisc[23:0] | 24'h000100; wire [23:0] subcode_dma_addr = subcode_address + {16'h0, subcode_off} + {16'h0, sub_idx}; wire [7:0] subcode_dma_byte = (sub_idx < 8'd96) ? subbuf[sub_idx[6:0]] : (sub_idx < 8'd98) ? 8'hff : 8'h00; wire tx_can_start = cdrom_flags[CDFLAG_TXD_BIT] && !cdrom_flags[CDFLAG_ENABLE_BIT] && (cdcomtxinx != cdcomtxcmp) && (tx_dma_delay == 2'd0) && (cdrom_receive_length == 6'd0) && (cdrom_command_length != 6'd32) && !cmd_pending; wire rx_can_start = cdrom_flags[CDFLAG_RXD_BIT] && (cdrom_receive_length != 6'd0) && (cdcomrxinx != cdcomrxcmp) && (rx_dma_delay == 2'd0); wire pio_tx_allowed = !cdrom_flags[CDFLAG_TXD_BIT] && !tx_busy; wire pio_tx_can_send = (cdrom_receive_length == 6'd0) && (cdrom_command_length != 6'd32) && !cmd_pending; wire [3:0] pio_tx_op = (cdrom_command_length == 6'd0) ? din[11:8] : cmd_op; wire [5:0] pio_tx_next_len = cdrom_command_length + 6'd1; wire pio_tx_more = (pio_tx_next_len < expected_total_len(pio_tx_op)) && (pio_tx_next_len != 6'd32); wire pio_rx_allowed = !cdrom_flags[CDFLAG_RXD_BIT] && !rx_busy; wire pio_rx_avail = pio_rx_allowed && (cdrom_receive_offset < cdrom_receive_length); wire [7:0] pio_rx_data = pio_rx_avail ? cdrom_result_buffer[cdrom_receive_offset] : pio_byte; wire pio_rx_last = (cdrom_receive_offset + 6'd1) == cdrom_receive_length; wire pbx_can_start = (pbx_state == PBX_IDLE) && cdrom_flags[CDFLAG_ENABLE_BIT] && cdrom_flags[CDFLAG_PBX_BIT] && (cdrom_pbx != 16'h0) && sector_ready; wire others_busy = rx_busy | pbx_busy | tx_busy; wire others_starting = rx_can_start | tx_can_start | pbx_can_start; wire [23:0] pbx_slot_base = cdrom_addressdata[23:0] + {8'h0, pbx_seccnt, 12'h0}; wire [23:0] pbx_addr_c = pbx_slot_base + ((pbx_state == PBX_DATA) ? {12'h0, pbx_byte_idx} : (24'h000c00 + {12'h0, pbx_byte_idx})); reg [23:0] pbx_addr; always @(posedge clk) begin if (reset) pbx_addr <= 24'h0; else pbx_addr <= pbx_addr_c; end reg [15:0] sector_rd_w; reg sector_rd_hi; always @(posedge clk) begin sector_rd_w <= sector_buffer[pbx_byte_idx[11:1]]; sector_rd_hi <= pbx_byte_idx[0]; end wire [7:0] sector_rd_q = sector_rd_hi ? sector_rd_w[15:8] : sector_rd_w[7:0]; wire [7:0] sector_byte_at_idx = (pbx_byte_idx < 12'd3 ) ? 8'h00 : (pbx_byte_idx == 12'd3 ) ? (cdrom_sector_counter & 8'h1f) : (pbx_byte_idx < 12'd2352) ? sector_rd_q : 8'h00; wire [7:0] pbx_wbyte = (pbx_state == PBX_DATA) ? sector_byte_at_idx : 8'h00; function [3:0] highest_bit; input [15:0] m; integer i; begin highest_bit = 4'd0; for (i = 0; i < 16; i = i + 1) if (m[i]) highest_bit = i[3:0]; end endfunction // wire sec_req_w = cdrom_flags[CDFLAG_ENABLE_BIT] && cdrom_flags[CDFLAG_PBX_BIT] && (cdrom_pbx != 16'h0) && !sector_ready && !pbx_busy; wire write = wr & cs; wire read = rd & cs; wire pio_wr_sel = write && (addr == 5'b10100) && uds; wire pio_rd_sel = read && (addr == 5'b10100); wire pio_wr_edge = pio_wr_sel & ~pio_wr_d; wire pio_rd_edge = pio_rd_sel & ~pio_rd_d; wire enable_rising = write && (addr == 5'b10010) && uds && din[10] && !cdrom_flags[CDFLAG_ENABLE_BIT]; wire pbx_starting = (pbx_state == PBX_IDLE) && cdrom_flags[CDFLAG_ENABLE_BIT] && cdrom_flags[CDFLAG_PBX_BIT] && (cdrom_pbx != 16'h0) && sector_ready && !subcode_busy; always @(posedge clk) begin if (reset) begin cdrom_intreq <= CDINT_SUBCODE; cdrom_intena <= 32'h0; cdrom_addressdata <= 32'h0; cdrom_addressmisc <= 32'h0; cdrom_flags <= 32'h0; cdrom_pbx <= 16'h0; cdrom_subcodeoffset <= 8'h0; cdcomtxinx <= 8'h0; cdcomrxinx <= 8'h0; cdcomtxcmp <= 8'h0; cdcomrxcmp <= 8'h0; pio_byte <= 8'h0; pio_wr_d <= 1'b0; pio_rd_d <= 1'b0; nvram_io <= 8'h0; nvram_dir <= 8'h0; cdrom_command_length <= 6'h0; cdrom_receive_length <= 6'h0; cdrom_receive_offset <= 6'h0; tx_dma_delay <= 2'h0; rx_dma_delay <= 2'h0; tx_busy <= 1'b0; rx_busy <= 1'b0; rx_inflight <= 1'b0; dma_owned <= 1'b0; dma_owner <= OWN_RX; hps_cmd_rd_ptr <= 6'h0; hps_result_wr_ptr <= 6'h0; sec_wr_ptr <= 11'h0; sector_ready <= 1'b0; sub_wr_ptr <= 7'h0; subcode_ready <= 1'b0; subcode_busy <= 1'b0; subcode_irq <= 1'b0; subcode_state <= SUB_IDLE; subcode_off <= 8'h0; sub_idx <= 8'h0; cdrom_sector_counter <= 8'h0; pbx_busy <= 1'b0; pbx_state <= PBX_IDLE; pbx_seccnt <= 4'h0; pbx_byte_idx <= 12'h0; pbx_ship_invalid <= 1'b0; end else begin if (tx_dma_delay != 2'd0) tx_dma_delay <= tx_dma_delay - 2'd1; if (rx_dma_delay != 2'd0) rx_dma_delay <= rx_dma_delay - 2'd1; pio_wr_d <= pio_wr_sel; pio_rd_d <= pio_rd_sel; if (dma_arm) begin dma_owned <= rx_busy | pbx_busy | tx_busy | subcode_busy; dma_owner <= rx_busy ? OWN_RX : pbx_busy ? OWN_PBX : tx_busy ? OWN_TX : OWN_SUB; end else if (dma_ack) begin dma_owned <= 1'b0; end if (write) begin case (addr) 5'b00100: begin : intena_hi reg [31:0] tmp; tmp = cdrom_intena; if (uds) tmp[31:24] = din[15:8]; if (lds) tmp[23:16] = din[7:0]; cdrom_intena <= tmp & INTENA_MASK; end 5'b00101: begin : intena_lo reg [31:0] tmp; tmp = cdrom_intena; if (uds) tmp[15:8] = din[15:8]; if (lds) tmp[7:0] = din[7:0]; cdrom_intena <= tmp & INTENA_MASK; end 5'b01000: begin : addrdata_hi reg [31:0] tmp; tmp = cdrom_addressdata; if (uds) tmp[31:24] = din[15:8]; if (lds) tmp[23:16] = din[7:0]; cdrom_addressdata <= tmp & ADDRDATA_MASK; end 5'b01001: begin : addrdata_lo reg [31:0] tmp; tmp = cdrom_addressdata; if (uds) tmp[15:8] = din[15:8]; if (lds) tmp[7:0] = din[7:0]; cdrom_addressdata <= tmp & ADDRDATA_MASK; end 5'b01010: begin : addrmisc_hi reg [31:0] tmp; tmp = cdrom_addressmisc; if (uds) tmp[31:24] = din[15:8]; if (lds) tmp[23:16] = din[7:0]; cdrom_addressmisc <= tmp & ADDRMISC_MASK; end 5'b01011: begin : addrmisc_lo reg [31:0] tmp; tmp = cdrom_addressmisc; if (uds) tmp[15:8] = din[15:8]; if (lds) tmp[7:0] = din[7:0]; cdrom_addressmisc <= tmp & ADDRMISC_MASK; end 5'b01100: begin if (uds) begin cdrom_intreq <= cdrom_intreq & ~CDINT_SUBCODE; subcode_irq <= 1'b0; end end 5'b01110: begin if (lds) begin cdcomtxcmp <= din[7:0]; cdrom_intreq <= cdrom_intreq & ~CDINT_TXDMADONE; tx_dma_delay <= 2'd3; end end 5'b01111: begin if (lds) begin cdcomrxcmp <= din[7:0]; cdrom_intreq <= cdrom_intreq & ~CDINT_RXDMADONE; rx_dma_delay <= 2'd3; end end 5'b10000: begin : pbx_w reg [15:0] tmp; tmp = cdrom_pbx; if (uds) tmp[15:8] = tmp[15:8] | din[15:8]; if (lds) tmp[7:0] = tmp[7:0] | din[7:0]; if (!cdrom_flags[CDFLAG_PBX_BIT]) tmp = 16'h0; cdrom_pbx <= tmp; cdrom_intreq <= cdrom_intreq & ~CDINT_PBX; end 5'b10010: begin : cfg_high reg [31:0] new_flags; new_flags = cdrom_flags; if (uds) new_flags[31:24] = din[15:8]; if (lds) new_flags[23:16] = din[7:0]; new_flags = new_flags & CONFIG_MASK; cdrom_flags <= new_flags; // if (new_flags[CDFLAG_ENABLE_BIT] && !cdrom_flags[CDFLAG_ENABLE_BIT]) begin cdrom_intreq <= cdrom_intreq & ~CDINT_OVERFLOW; cdrom_sector_counter <= 8'h0; sector_ready <= 1'b0; sec_wr_ptr <= 11'h0; end if (!new_flags[CDFLAG_PBX_BIT]) cdrom_pbx <= 16'h0; end 5'b10011: begin : cfg_low reg [31:0] new_flags; new_flags = cdrom_flags; if (uds) new_flags[15:8] = din[15:8]; if (lds) new_flags[7:0] = din[7:0]; new_flags = new_flags & CONFIG_MASK; cdrom_flags <= new_flags; end 5'b10100: begin if (pio_wr_edge && pio_tx_allowed) begin cdrom_intreq <= (cdrom_intreq & ~CDINT_DRIVEXMIT) | ((pio_tx_can_send && pio_tx_more) ? CDINT_DRIVEXMIT : 32'h0); if (pio_tx_can_send) begin cdrom_command_buffer[cdrom_command_length] <= din[15:8]; cdrom_command_length <= pio_tx_next_len; end end end 5'b11000: begin if (uds) nvram_io <= din[15:8]; if (lds) ; end 5'b11001: begin if (uds) nvram_dir <= din[15:8]; end default: ; endcase end if (pio_rd_edge) begin pio_byte <= pio_rx_data; if (pio_rx_avail) begin cdrom_receive_offset <= cdrom_receive_offset + 6'd1; if (pio_rx_last) begin cdrom_receive_length <= 6'd0; cdrom_receive_offset <= 6'd0; cdrom_intreq <= (cdrom_intreq & ~CDINT_DRIVERECV) | CDINT_DRIVEXMIT; end end else begin cdrom_intreq <= cdrom_intreq & ~CDINT_DRIVERECV; end end if (tx_busy) begin if (dma_ack && own_tx) begin if (cdrom_command_length != 6'd32) cdrom_command_buffer[cdrom_command_length] <= dma_rbyte; cdrom_command_length <= cdrom_command_length + 6'd1; cdcomtxinx <= cdcomtxinx + 8'd1; if ((cdcomtxinx + 8'd1) == cdcomtxcmp) cdrom_intreq <= cdrom_intreq | CDINT_TXDMADONE; tx_busy <= 1'b0; end end else if (!rx_busy && !pbx_busy && tx_can_start && !subcode_busy) begin tx_busy <= 1'b1; end // if (rx_busy) begin if (dma_ack && own_rx) begin cdcomrxinx <= cdcomrxinx + 8'd1; cdrom_receive_offset <= cdrom_receive_offset + 6'd1; if ((cdrom_receive_offset + 6'd1) == cdrom_receive_length) begin cdrom_receive_length <= 6'd0; cdrom_receive_offset <= 6'd0; cdrom_intreq <= ((cdrom_intreq & ~CDINT_DRIVERECV) | CDINT_DRIVEXMIT) | (((cdcomrxinx + 8'd1) == cdcomrxcmp) ? CDINT_RXDMADONE : 32'h0); end else if ((cdcomrxinx + 8'd1) == cdcomrxcmp) begin // cdrom_intreq <= cdrom_intreq | CDINT_RXDMADONE; end rx_busy <= 1'b0; rx_inflight <= 1'b0; end else if (!rx_inflight && !dma_ack) begin rx_inflight <= 1'b1; end end else if (rx_can_start && !subcode_busy) begin rx_busy <= 1'b1; rx_inflight <= 1'b0; end case (pbx_state) PBX_IDLE: begin if (cdrom_flags[CDFLAG_ENABLE_BIT] && cdrom_flags[CDFLAG_PBX_BIT] && (cdrom_pbx != 16'h0) && sector_ready && !subcode_busy) begin pbx_seccnt <= highest_bit(cdrom_pbx); pbx_byte_idx <= 12'h0; pbx_busy <= 1'b1; pbx_state <= PBX_DATA; end end PBX_DATA: begin if (dma_ack && own_pbx) begin if (pbx_byte_idx == 12'd2351) begin pbx_byte_idx <= 12'h0; pbx_state <= PBX_ZERO; end else begin pbx_byte_idx <= pbx_byte_idx + 12'd1; end end end PBX_ZERO: begin if (dma_ack && own_pbx) begin if (pbx_byte_idx == 12'd145) begin pbx_byte_idx <= 12'h0; pbx_state <= PBX_FIN; end else begin pbx_byte_idx <= pbx_byte_idx + 12'd1; end end end PBX_FIN: begin cdrom_pbx[pbx_seccnt] <= 1'b0; cdrom_intreq <= cdrom_intreq | CDINT_PBX; if (!pbx_ship_invalid && !enable_rising) cdrom_sector_counter <= cdrom_sector_counter + 8'd1; sector_ready <= 1'b0; pbx_busy <= 1'b0; pbx_state <= PBX_IDLE; end endcase if (enable_rising && (pbx_busy || pbx_starting)) pbx_ship_invalid <= 1'b1; else if (pbx_starting) pbx_ship_invalid <= 1'b0; if (sec_w_we && !sector_ready && !enable_rising) begin sector_buffer[sec_w_addr] <= sec_w_din; end if (hps_sec_push && !sector_ready && sec_wr_ptr != 11'd1176 && !enable_rising) begin sec_wr_ptr <= sec_wr_ptr + 11'd1; end if (hps_sec_done) begin if (sec_wr_ptr == 11'd1176 && !enable_rising) sector_ready <= 1'b1; sec_wr_ptr <= 11'h0; end if (hps_subcode_push && !subcode_ready && !subcode_busy && sub_wr_ptr != 7'd96) begin subbuf[sub_wr_ptr[6:0]] <= hps_subcode_byte; sub_wr_ptr <= sub_wr_ptr + 7'd1; end if (hps_subcode_done) begin if (sub_wr_ptr == 7'd96 && !subcode_busy) subcode_ready <= 1'b1; sub_wr_ptr <= 7'h0; end case (subcode_state) SUB_IDLE: begin if (subcode_ready) begin if (!cdrom_flags[CDFLAG_SUBCODE_BIT]) begin subcode_ready <= 1'b0; end else if (!others_busy && !others_starting) begin subcode_off <= (cdrom_subcodeoffset >= 8'd128) ? 8'd0 : 8'd128; sub_idx <= 8'h0; subcode_busy <= 1'b1; subcode_state <= SUB_DATA; end end end SUB_DATA: begin if (dma_ack && own_sub) begin if (sub_idx == 8'd99) subcode_state <= SUB_FIN; else sub_idx <= sub_idx + 8'd1; end end SUB_FIN: begin cdrom_subcodeoffset <= subcode_off + 8'd100; subcode_irq <= 1'b1; subcode_ready <= 1'b0; subcode_busy <= 1'b0; subcode_state <= SUB_IDLE; end endcase if (hps_cmd_pop && (hps_cmd_rd_ptr != 6'd32)) hps_cmd_rd_ptr <= hps_cmd_rd_ptr + 6'd1; if (hps_cmd_done) begin cdrom_command_length <= 6'd0; hps_cmd_rd_ptr <= 6'd0; end if (hps_cmd_done && cmd_zero_result && !hps_result_done) cdrom_intreq <= cdrom_intreq | CDINT_DRIVEXMIT; if (hps_result_push && (hps_result_wr_ptr != 6'd32)) begin cdrom_result_buffer[hps_result_wr_ptr[4:0]] <= hps_result_byte; hps_result_wr_ptr <= hps_result_wr_ptr + 6'd1; end if (hps_result_done && (cdrom_receive_length == 6'd0)) begin cdrom_receive_length <= hps_result_wr_ptr; hps_result_wr_ptr <= 6'd0; if (hps_result_wr_ptr != 6'd0) cdrom_intreq <= cdrom_intreq | CDINT_DRIVERECV; end end end wire [31:0] cdrom_intreq_eff = cdrom_intreq | (subcode_irq ? CDINT_SUBCODE : 32'h0); reg [15:0] cd_dout_r; always @(*) begin cd_dout_r = 16'h0; case (addr) 5'b00010: cd_dout_r = cdrom_intreq_eff[31:16]; 5'b00011: cd_dout_r = cdrom_intreq_eff[15:0]; 5'b00100: cd_dout_r = cdrom_intena[31:16]; 5'b00101: cd_dout_r = cdrom_intena[15:0]; 5'b00110: cd_dout_r = cdrom_intena[31:16]; 5'b00111: cd_dout_r = cdrom_intena[15:0]; 5'b01000, 5'b01010, 5'b01100, 5'b01110: cd_dout_r = {cdrom_subcodeoffset, cdcomtxinx}; 5'b01001, 5'b01011, 5'b01101, 5'b01111: cd_dout_r = {cdcomrxinx, 8'h0}; 5'b10000: cd_dout_r = cdrom_pbx; 5'b10010: cd_dout_r = cdrom_flags[31:16]; 5'b10011: cd_dout_r = cdrom_flags[15:0]; 5'b10100: cd_dout_r = {pio_rx_data, 8'h0}; 5'b11000: cd_dout_r = {nvram_scl_bus, nvram_sda_bus, 6'h0, 8'h0}; 5'b11001: cd_dout_r = {nvram_dir, 8'h0}; default: cd_dout_r = 16'h0; endcase end assign cd_dout = cs ? cd_dout_r : 16'h0; assign cd_irq = |(cdrom_intreq_eff[31:25] & cdrom_intena[31:25]); wire subcode_grant = subcode_busy & ~rx_busy & ~pbx_busy & ~tx_busy; assign cd_dma_req = tx_busy | rx_busy | pbx_busy | subcode_busy; assign cd_dma_we = rx_busy | pbx_busy | subcode_grant; assign cd_dma_baddr = rx_busy ? (cdrx_address + {16'h0, cdcomrxinx}) : pbx_busy ? pbx_addr : tx_busy ? (cdtx_address + {16'h0, cdcomtxinx}) : subcode_dma_addr; assign cd_dma_wbyte = rx_busy ? cdrom_result_buffer[cdrom_receive_offset] : pbx_busy ? pbx_wbyte : subcode_dma_byte; assign cd_hps_cmd_pending = cmd_pending; assign cd_hps_cmd_byte = cdrom_command_buffer[hps_cmd_rd_ptr[4:0]]; assign cd_hps_sec_req = sec_req_w; assign cd_hps_sec_status = cdrom_sector_counter; assign cd_hps_rx_busy = (cdrom_receive_length != 6'd0); akiko_nvram nvram_inst ( .clk (clk), .reset (1'b0), .scl_in (nvram_scl_bus), .sda_in (nvram_sda_bus), .sda_drive (nvram_slave_sda_drive), .host_addr (hps_nvr_addr), .host_dout (cd_hps_nvr_dout), .host_clear_dirty (hps_nvr_clear_dirty), .nvram_dirty (cd_hps_nvr_dirty), .load_addr (nvr_load_addr), .load_din (nvr_load_din), .load_we (nvr_load_we) ); end else begin : g_stub assign cd_dout = 16'h0; assign cd_irq = 1'b0; assign cd_dma_req = 1'b0; assign cd_dma_we = 1'b0; assign cd_dma_baddr = 24'h0; assign cd_dma_wbyte = 8'h0; assign cd_hps_cmd_pending = 1'b0; assign cd_hps_cmd_byte = 8'h0; assign cd_hps_sec_req = 1'b0; assign cd_hps_sec_status = 8'h0; assign cd_hps_rx_busy = 1'b0; assign cd_hps_nvr_dout = 8'h0; assign cd_hps_nvr_dirty = 1'b0; end endgenerate always @(*) begin dout = 16'h0; if (cs) begin if (addr == 5'd0) dout = 16'hC0CA; if (addr == 5'd1) dout = 16'hCAFE; if (c2p_sel) dout = c2p_dout; end dout = dout | cd_dout; end assign akiko_irq = cd_irq; assign dma_req = cd_dma_req; assign dma_we = cd_dma_we; assign dma_baddr = cd_dma_baddr; assign dma_wbyte = cd_dma_wbyte; assign hps_cmd_pending = cd_hps_cmd_pending; assign hps_cmd_byte = cd_hps_cmd_byte; assign hps_sec_req = cd_hps_sec_req; assign hps_sec_status = cd_hps_sec_status; assign hps_rx_busy = cd_hps_rx_busy; assign hps_nvr_dout = cd_hps_nvr_dout; assign hps_nvr_dirty = cd_hps_nvr_dirty; endmodule