//============================================================================
//  TSConf for MiSTer
// 
//  Port to MiSTer
//  Copyright (C) 2017-2019 Sorgelig
//
//  This program 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 2 of the License, or (at your option)
//  any later version.
//
//  This program 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, write to the Free Software Foundation, Inc.,
//  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//============================================================================

module TSConf_top
(
	input         CLOCK_27,

	output        LED,
	output [VGA_BITS-1:0] VGA_R,
	output [VGA_BITS-1:0] VGA_G,
	output [VGA_BITS-1:0] VGA_B,
	output        VGA_HS,
	output        VGA_VS,

	input         SPI_SCK,
	inout         SPI_DO,
	input         SPI_DI,
	input         SPI_SS2,    // data_io
	input         SPI_SS3,    // OSD
	input         CONF_DATA0, // SPI_SS for user_io

	input         SPI_SS4,

	output [12:0] SDRAM_A,
	inout  [15:0] SDRAM_DQ,
	output        SDRAM_DQML,
	output        SDRAM_DQMH,
	output        SDRAM_nWE,
	output        SDRAM_nCAS,
	output        SDRAM_nRAS,
	output        SDRAM_nCS,
	output  [1:0] SDRAM_BA,
	output        SDRAM_CLK,
	output        SDRAM_CKE,

	output        AUDIO_L,
	output        AUDIO_R,

	input         UART_RX,
	output        UART_TX
);

localparam VGA_BITS = 6;
localparam bit BIG_OSD = 1;


assign LED = ~ioctl_download & UART_TX & UART_RX;
assign UART_TX = 1'b1;


`include "build_id.v"
localparam CONF_STR = {
	"TSConf;;",
	"O12,Scandoubler Fx,None,CRT 25%,CRT 50%,CRT 75%;",
	"-;",
	"O34,Stereo mix,None,25%,50%,100%;",
	"OST,General Sound,512KB,1MB,2MB;",
	"-;",
	"OU,CPU Type,NMOS,CMOS;",
	"O67,CPU Speed,3.5MHz,7MHz,14MHz;",
	"O8,CPU Cache,On,Off;",
	"O9A,#7FFD span,128K,128K Auto,1024K,512K;",
	"OLN,ZX Palette,Default,B.black,Light,Pale,Dark,Grayscale,Custom;",
	"OPR,INT Offset,1,2,3,4,5,6,7,0;",
	"-;",
	"OBD,F11 Reset,boot.$C,sys.rom,ROM;",
	"OEF,           bank,TR-DOS,Basic 48,Basic 128,SYS;",
	"OGI,Shift+F11 Reset,ROM,boot.$C,sys.rom;",
	"OJK,           bank,Basic 128,SYS,TR-DOS,Basic 48;",
	"-;",
	"T0,Reset and apply settings;",
	"V,v",`BUILD_DATE
};

wire [27:0] CMOSCfg;

// fix default values
assign CMOSCfg[5:0]  = 0;
assign CMOSCfg[7:6]  = status[7:6];
assign CMOSCfg[8]    = ~status[8];
assign CMOSCfg[10:9] = status[10:9] + 1'd1;
assign CMOSCfg[13:11]= (status[13:11] < 2) ? status[13:11] + 3'd3 : status[13:11] - 3'd2;
assign CMOSCfg[15:14]= status[15:14];
assign CMOSCfg[18:16]= (status[18:16]) ? status[18:16] + 3'd2 : 3'd0;
assign CMOSCfg[20:19]= status[20:19] + 2'd2;
assign CMOSCfg[23:21]= status[23:21];
assign CMOSCfg[24]   = 0;
assign CMOSCfg[27:25]= status[27:25] + 1'd1;


////////////////////   CLOCKS   ///////////////////
wire clk_sys;
wire locked;

pll pll
(
	.inclk0(CLOCK_27),
	.c0(clk_sys),
	.locked(locked)
);

reg ce_28m;
always @(negedge clk_sys) begin
	reg [1:0] div;
	
	div <= div + 1'd1;
	if(div == 2) div <= 0;
	ce_28m <= !div;
end


//////////////////   MIST ARM I/O   ///////////////////
wire  [7:0] joystick_0;
wire  [7:0] joystick_1;

wire  [1:0] buttons;
wire  [1:0] switches;
wire        scandoubler_disable;
wire        ypbpr;
wire        no_csync;
wire [63:0] status;

wire [63:0] rtc;

wire        sd_busy_mmc;
wire        sd_rd_mmc;
wire        sd_wr_mmc;
wire [31:0] sd_lba_mmc;
wire  [7:0] sd_buff_din_mmc;

wire [31:0] sd_lba = sd_lba_mmc;
wire  [1:0] sd_rd = { 1'b0, sd_rd_mmc };
wire  [1:0] sd_wr = { 1'b0, sd_wr_mmc };

wire        sd_ack;
wire  [8:0] sd_buff_addr;
wire  [7:0] sd_buff_dout;
wire  [7:0] sd_buff_din = sd_buff_din_mmc;
wire        sd_buff_wr;
wire  [1:0] img_mounted;
wire [63:0] img_size;

wire        sd_ack_conf;
wire        sd_conf;
wire        sd_sdhc;

wire        key_strobe;
wire        key_pressed;
wire        key_extended;
wire  [7:0] key_code;

wire  [8:0] mouse_x;
wire  [8:0] mouse_y;
wire  [7:0] mouse_flags;
wire        mouse_strobe;

wire [24:0] ps2_mouse = { mouse_strobe_level, mouse_y[7:0], mouse_x[7:0], mouse_flags };
reg         mouse_strobe_level;
always @(posedge clk_sys) if (mouse_strobe) mouse_strobe_level <= ~mouse_strobe_level;

user_io #(.STRLEN($size(CONF_STR)>>3), .SD_IMAGES(2), .FEATURES(32'h0 | (BIG_OSD << 13))) user_io
(
	.clk_sys(clk_sys),
	.clk_sd(clk_sys),
	.conf_str(CONF_STR),

	.SPI_CLK(SPI_SCK),
	.SPI_SS_IO(CONF_DATA0),
	.SPI_MOSI(SPI_DI),
	.SPI_MISO(SPI_DO),

	.img_mounted(img_mounted),
	.img_size(img_size),
	.sd_conf(sd_conf),
	.sd_ack_conf(sd_ack_conf),
	.sd_sdhc(sd_sdhc),
	.sd_lba(sd_lba),
	.sd_rd(sd_rd),
	.sd_wr(sd_wr),
	.sd_ack(sd_ack),
	.sd_buff_addr(sd_buff_addr),
	.sd_din(sd_buff_din),
	.sd_dout(sd_buff_dout),
	.sd_dout_strobe(sd_buff_wr),

	.key_strobe(key_strobe),
	.key_code(key_code),
	.key_pressed(key_pressed),
	.key_extended(key_extended),

	.mouse_x(mouse_x),
	.mouse_y(mouse_y),
	.mouse_flags(mouse_flags),
	.mouse_strobe(mouse_strobe),

	.joystick_0(joystick_0),
	.joystick_1(joystick_1),

	.buttons(buttons),
	.status(status),
	.scandoubler_disable(scandoubler_disable),
	.ypbpr(ypbpr),
	.no_csync(no_csync),
	.rtc(rtc)
);

wire        ioctl_wr;
wire [24:0] ioctl_addr;
wire  [7:0] ioctl_dout;
wire        ioctl_download;
wire  [5:0] ioctl_index;
wire  [1:0] ioctl_ext_index;

data_io data_io
(
	.clk_sys(clk_sys),

	.SPI_SCK(SPI_SCK),
	.SPI_SS2(SPI_SS2),
	.SPI_DI(SPI_DI),
	.SPI_DO(SPI_DO),

	.clkref_n(1'b0),
	.ioctl_wr(ioctl_wr),
	.ioctl_addr(ioctl_addr),
	.ioctl_dout(ioctl_dout),
	.ioctl_download(ioctl_download),
	.ioctl_index({ioctl_ext_index, ioctl_index})
);


reg init_reset = 1;
reg old_download;
always @(posedge clk_sys) begin
	old_download <= ioctl_download;
	if(old_download & ~ioctl_download) init_reset <= 0;
end


//////////////////   SD   ///////////////////
wire        sdss;
wire        sdclk;
wire        sdmiso;
wire        sdmosi;
sd_card sd_card
(
	.clk_sys(clk_sys),
	.img_mounted(img_mounted[0]), //first slot for SD-card emulation
	.img_size(img_size),
	.sd_busy(sd_busy_mmc),
	.sd_rd(sd_rd_mmc),
	.sd_wr(sd_wr_mmc),
	.sd_lba(sd_lba_mmc),

	.sd_buff_din(sd_buff_din_mmc),
	.sd_buff_dout(sd_buff_dout),
	.sd_buff_wr(sd_buff_wr),
	.sd_buff_addr(sd_buff_addr),

	.sd_ack(sd_ack),
	.sd_ack_conf(sd_ack_conf),

	.allow_sdhc(1),
	.sd_sdhc(sd_sdhc),
	.sd_conf(sd_conf),

	.sd_cs(sdss),
	.sd_sck(sdclk),
	.sd_sdi(sdmosi),
	.sd_sdo(sdmiso)
);


////////////////////  MAIN  //////////////////////
wire [7:0] R,G,B;
wire HBlank,VBlank;
wire VS, HS;
wire ce_vid;
wire [15:0] SOUND_L;
wire [15:0] SOUND_R;

tsconf tsconf
(
	.clk(clk_sys),
	.ce(ce_28m),

	.SDRAM_DQ(SDRAM_DQ),
	.SDRAM_A(SDRAM_A),
	.SDRAM_BA(SDRAM_BA),
	.SDRAM_DQML(SDRAM_DQML),
	.SDRAM_DQMH(SDRAM_DQMH),
	.SDRAM_nWE(SDRAM_nWE),
	.SDRAM_nCAS(SDRAM_nCAS),
	.SDRAM_nRAS(SDRAM_nRAS),
	.SDRAM_CKE(SDRAM_CKE),
	.SDRAM_nCS(SDRAM_nCS),
	.SDRAM_CLK(SDRAM_CLK),

	.VGA_R(R),
	.VGA_G(G),
	.VGA_B(B),
	.VGA_HS(HS),
	.VGA_VS(VS),
	.VGA_HBLANK(HBlank),
	.VGA_VBLANK(VBlank),
	.VGA_CEPIX(ce_vid),

	.SD_SO(sdmiso),
	.SD_SI(sdmosi),
	.SD_CLK(sdclk),
	.SD_CS_N(sdss),

	.GS_ADDR(gs_mem_addr),
	.GS_DI(gs_mem_din),
	.GS_DO(gs_mem_dout | gs_mem_mask),
	.GS_RD(gs_mem_rd),
	.GS_WR(gs_mem_wr),
	.GS_WAIT(~gs_mem_ready),
	.SOUND_L(SOUND_L),
	.SOUND_R(SOUND_R),

	.COLD_RESET(init_reset | status[0]),
	.WARM_RESET(buttons[1]),
	.RTC(rtc),
	.OUT0(status[30]),

	.CMOSCfg(CMOSCfg),

	.PS2_KEY({key_strobe,key_pressed,key_extended,key_code}),
	.PS2_MOUSE(ps2_mouse),
	.joystick(joystick_0[5:0] | joystick_1[5:0]),

	.loader_act(ioctl_download),
	.loader_addr(ioctl_addr[15:0]),
	.loader_data(ioctl_dout),
	.loader_wr(ioctl_wr && ioctl_download && !ioctl_index && !ioctl_addr[24:16])
);

wire [20:0] gs_mem_addr;
wire  [7:0] gs_mem_dout;
wire  [7:0] gs_mem_din;
wire        gs_mem_rd;
wire        gs_mem_wr;
wire        gs_mem_ready;
reg   [7:0] gs_mem_mask;

always_comb begin
	gs_mem_mask = 0;
	case(status[29:28])
		0: if(gs_mem_addr[20:19]) gs_mem_mask = 8'hFF;
		1: if(gs_mem_addr[20])    gs_mem_mask = 8'hFF;
	 2,3:                        gs_mem_mask = 0;
	endcase
end

// ddram ddram
// (
// 	.*,
// 	.addr(gs_mem_addr),
// 	.dout(gs_mem_dout),
// 	.din(gs_mem_din),
// 	.we(gs_mem_wr),
// 	.rd(gs_mem_rd),
// 	.ready(gs_mem_ready)
// );


reg VSync, HSync;
always @(posedge clk_sys) begin
	HSync <= HS;
	if(~HSync & HS) VSync <= VS;
end


//////////////////   VIDEO   ///////////////////
mist_video #(.COLOR_DEPTH(8), .SD_HCNT_WIDTH(11), .OUT_COLOR_DEPTH(VGA_BITS), .BIG_OSD(BIG_OSD)) mist_video (
	.clk_sys     ( clk_sys    ),

	// OSD SPI interface
	.SPI_SCK     ( SPI_SCK    ),
	.SPI_SS3     ( SPI_SS3    ),
	.SPI_DI      ( SPI_DI     ),

	// scanlines (00-none 01-25% 10-50% 11-75%)
	// .scanlines   ( status[2:1]  ),

	// non-scandoubled pixel clock divider 0 - clk_sys/4, 1 - clk_sys/2
	.ce_divider  ( 3'd2       ),

	// 0 = HVSync 31KHz, 1 = CSync 15KHz
	.scandoubler_disable ( scandoubler_disable ),
	// disable csync without scandoubler
	.no_csync    ( no_csync   ),
	// YPbPr always uses composite sync
	.ypbpr       ( ypbpr      ),
	// Rotate OSD [0] - rotate [1] - left or right
	.rotate      ( 2'b00      ),
	// composite-like blending
	.blend       ( 1'b0       ),

	// video in
	.R           ( R ),
	.G           ( G ),
	.B           ( B ),

	.HSync       ( HSync      ),
	.VSync       ( VSync      ),

	// MiST video output signals
	.VGA_R       ( VGA_R      ),
	.VGA_G       ( VGA_G      ),
	.VGA_B       ( VGA_B      ),
	.VGA_VS      ( VGA_VS     ),
	.VGA_HS      ( VGA_HS     )
);


//////////////////   SOUND   ///////////////////
// dac #(.C_bits(16)) dac_l (
// 	.clk_i(clk_sys),
// 	.res_n_i(~init_reset),
// 	.dac_i(SOUND_L),
// 	.dac_o(AUDIO_L)
// );

// dac #(.C_bits(16)) dac_r (
// 	.clk_i(clk_sys),
// 	.res_n_i(~init_reset),
// 	.dac_i(SOUND_R),
// 	.dac_o(AUDIO_R)
// );


endmodule