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FPGA: rework shared memory access FSM

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This commit is contained in:
Maximilian Rehkopf 2012-07-09 02:12:59 +02:00
parent 006ea8c44a
commit 7df6909266
4 changed files with 325 additions and 284 deletions
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240
verilog/sd2snes/main.v
View File

@ -472,16 +472,20 @@ parameter ST_MCU_WR_WAIT = 18'b000100000000000000;
parameter ST_MCU_WR_WAIT2 = 18'b001000000000000000; parameter ST_MCU_WR_WAIT2 = 18'b001000000000000000;
parameter ST_MCU_WR_END = 18'b010000000000000000; parameter ST_MCU_WR_END = 18'b010000000000000000;
parameter ROM_RD_WAIT = 4'h4; parameter ROM_RD_WAIT = 4'h0;
parameter ROM_RD_WAIT_MCU = 4'h6; parameter ROM_RD_WAIT_MCU = 4'h6;
parameter ROM_WR_WAIT = 4'h4;
parameter ROM_WR_WAIT1 = 4'h2; parameter ROM_WR_WAIT1 = 4'h2;
parameter ROM_WR_WAIT2 = 4'h3; parameter ROM_WR_WAIT2 = 4'h1;
parameter ROM_WR_WAIT_MCU = 4'h6; parameter ROM_WR_WAIT_MCU = 4'h5;
parameter SNES_DEAD_TIMEOUT = 17'd88000; // 1ms
reg [17:0] STATE; reg [17:0] STATE;
initial STATE = ST_IDLE; initial STATE = ST_IDLE;
reg [7:0] SNES_DINr; reg [7:0] SNES_DINr;
reg [7:0] SNES_DOUTr;
reg [7:0] ROM_DOUTr; reg [7:0] ROM_DOUTr;
assign DSPX_SNES_DATA_IN = SNES_DATA; assign DSPX_SNES_DATA_IN = SNES_DATA;
@ -508,7 +512,7 @@ assign SNES_DATA = (snescmd_rd_enable & ~SNES_PARD) ? snescmd_regs[SNES_ADDR[3:0
:dspx_dp_enable ? DSPX_SNES_DATA_OUT :dspx_dp_enable ? DSPX_SNES_DATA_OUT
:msu_enable ? MSU_SNES_DATA_OUT :msu_enable ? MSU_SNES_DATA_OUT
:bsx_data_ovr ? BSX_SNES_DATA_OUT :bsx_data_ovr ? BSX_SNES_DATA_OUT
:SNES_DINr /*(ROM_ADDR0 ? ROM_DATA[7:0] : ROM_DATA[15:8])*/) : 8'bZ; :SNES_DOUTr /*(ROM_ADDR0 ? ROM_DATA[7:0] : ROM_DATA[15:8])*/) : 8'bZ;
reg [3:0] ST_MEM_DELAYr; reg [3:0] ST_MEM_DELAYr;
reg MCU_RD_PENDr; reg MCU_RD_PENDr;
@ -520,25 +524,35 @@ always @(posedge CLK2) begin
else if(STATE & (ST_SNES_RD_END | ST_SNES_WR_END)) NEED_SNES_ADDRr <= 1'b0; else if(STATE & (ST_SNES_RD_END | ST_SNES_WR_END)) NEED_SNES_ADDRr <= 1'b0;
end end
wire ASSERT_SNES_ADDR = SNES_CPU_CLK & NEED_SNES_ADDRr;
assign ROM_ADDR = (SD_DMA_TO_ROM) ? MCU_ADDR[23:1] : (ASSERT_SNES_ADDR) ? MAPPED_SNES_ADDR[23:1] : ROM_ADDRr[23:1];
assign ROM_ADDR0 = (SD_DMA_TO_ROM) ? MCU_ADDR[0] : (ASSERT_SNES_ADDR) ? MAPPED_SNES_ADDR[0] : ROM_ADDRr[0];
reg ROM_WEr;
initial ROM_WEr = 1'b1;
reg RQ_MCU_RDYr; reg RQ_MCU_RDYr;
initial RQ_MCU_RDYr = 1'b1; initial RQ_MCU_RDYr = 1'b1;
assign MCU_RDY = RQ_MCU_RDYr; assign MCU_RDY = RQ_MCU_RDYr;
reg ROM_SAr;
initial ROM_SAr = 1'b1;
//wire ROM_SA = SNES_FAKE_CLK | ((STATE == ST_IDLE) ^ (~RQ_MCU_RDYr & SNES_cycle_end));
wire ROM_SA = ROM_SAr;
assign ROM_ADDR = (SD_DMA_TO_ROM) ? MCU_ADDR[23:1] : (ROM_SA) ? MAPPED_SNES_ADDR[23:1] : ROM_ADDRr[23:1];
assign ROM_ADDR0 = (SD_DMA_TO_ROM) ? MCU_ADDR[0] : (ROM_SA) ? MAPPED_SNES_ADDR[0] : ROM_ADDRr[0];
reg ROM_WEr;
initial ROM_WEr = 1'b1;
reg ROM_DOUT_ENr;
initial ROM_DOUT_ENr = 1'b0;
reg[17:0] SNES_DEAD_CNTr;
initial SNES_DEAD_CNTr = 0;
always @(posedge CLK2) begin always @(posedge CLK2) begin
if(MCU_RRQ) begin if(MCU_RRQ) begin
MCU_RD_PENDr <= 1'b1; MCU_RD_PENDr <= 1'b1;
RQ_MCU_RDYr <= 1'b0; RQ_MCU_RDYr <= 1'b0;
ROM_ADDRr <= MCU_ADDR;
end else if(MCU_WRQ) begin end else if(MCU_WRQ) begin
MCU_WR_PENDr <= 1'b1; MCU_WR_PENDr <= 1'b1;
RQ_MCU_RDYr <= 1'b0; RQ_MCU_RDYr <= 1'b0;
ROM_ADDRr <= MCU_ADDR;
end else if(STATE & (ST_MCU_RD_END | ST_MCU_WR_END)) begin end else if(STATE & (ST_MCU_RD_END | ST_MCU_WR_END)) begin
MCU_RD_PENDr <= 1'b0; MCU_RD_PENDr <= 1'b0;
MCU_WR_PENDr <= 1'b0; MCU_WR_PENDr <= 1'b0;
@ -546,115 +560,119 @@ always @(posedge CLK2) begin
end end
end end
always @(posedge CLK2) begin
if(~SNES_CPU_CLK) SNES_DEAD_CNTr <= SNES_DEAD_CNTr + 1;
else SNES_DEAD_CNTr <= 17'h0;
end
always @(posedge CLK2) begin
if(SNES_DEAD_CNTr > SNES_DEAD_TIMEOUT) SNES_DEADr <= 1'b1;
else if(SNES_CPU_CLK) SNES_DEADr <= 1'b0;
end
reg snes_wr_cycle; reg snes_wr_cycle;
always @(posedge CLK2) begin always @(posedge CLK2) begin
if(SNES_cycle_start & ~SNES_WR_start) begin if(SNES_DEADr & SNES_CPU_CLK) STATE <= ST_IDLE; // interrupt+restart an ongoing MCU access when the SNES comes alive
STATE <= ST_SNES_RD_ADDR; else
end else if(SNES_WR_start) begin case(STATE)
STATE <= ST_SNES_WR_ADDR; ST_IDLE: begin
end else begin ROM_SAr <= 1'b1;
case(STATE) ROM_DOUT_ENr <= 1'b0;
ST_IDLE: begin if(SNES_cycle_start & ~SNES_WRITE) begin
ROM_ADDRr <= MAPPED_SNES_ADDR; STATE <= ST_SNES_WR_ADDR;
if(MCU_RD_PENDr) STATE <= ST_MCU_RD_ADDR; if(IS_SAVERAM | IS_WRITABLE | IS_FLASHWR) begin
else if(MCU_WR_PENDr) STATE <= ST_MCU_WR_ADDR; ROM_WEr <= 1'b0;
else STATE <= ST_IDLE; ROM_DOUT_ENr <= 1'b1;
end
end else if(SNES_cycle_start) begin
// STATE <= ST_SNES_RD_ADDR;
STATE <= ST_SNES_RD_END;
SNES_DOUTr <= (ROM_ADDR0 ? ROM_DATA[7:0] : ROM_DATA[15:8]);
end else if(SNES_DEADr & MCU_RD_PENDr) begin
STATE <= ST_MCU_RD_ADDR;
end else if(SNES_DEADr & MCU_WR_PENDr) begin
STATE <= ST_MCU_WR_ADDR;
end end
ST_SNES_RD_ADDR: begin end
STATE <= ST_SNES_RD_WAIT; ST_SNES_RD_ADDR: begin
ST_MEM_DELAYr <= ROM_RD_WAIT; ST_MEM_DELAYr <= ROM_RD_WAIT;
end STATE <= ST_SNES_RD_WAIT;
ST_SNES_RD_WAIT: begin end
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; ST_SNES_RD_WAIT: begin
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_SNES_RD_END; ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
else STATE <= ST_SNES_RD_WAIT; // if(ST_MEM_DELAYr == 0) begin
if(ROM_ADDR0) SNES_DINr <= ROM_DATA[7:0]; // end
else SNES_DINr <= ROM_DATA[15:8]; // else STATE <= ST_SNES_RD_WAIT;
end end
ST_SNES_RD_END: begin
STATE <= ST_IDLE; ST_SNES_WR_ADDR: begin
if(ROM_ADDR0) SNES_DINr <= ROM_DATA[7:0]; ST_MEM_DELAYr <= ROM_WR_WAIT1;
else SNES_DINr <= ROM_DATA[15:8]; STATE <= ST_SNES_WR_WAIT1;
end end
ST_SNES_WR_ADDR: begin ST_SNES_WR_WAIT1: begin
ROM_WEr <= (!IS_FLASHWR & !IS_WRITABLE); ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
snes_wr_cycle <= 1'b1; if(ST_MEM_DELAYr == 0) begin
STATE <= ST_SNES_WR_WAIT1;
ST_MEM_DELAYr <= ROM_WR_WAIT1;
end
ST_SNES_WR_WAIT1: begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1;
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_SNES_WR_DATA;
else STATE <= ST_SNES_WR_WAIT1;
end
ST_SNES_WR_DATA: begin
ROM_DOUTr <= SNES_DATA;
ST_MEM_DELAYr <= ROM_WR_WAIT2; ST_MEM_DELAYr <= ROM_WR_WAIT2;
STATE <= ST_SNES_WR_WAIT2; STATE <= ST_SNES_WR_WAIT2;
ROM_DOUTr <= SNES_DATA;
end end
ST_SNES_WR_WAIT2: begin else STATE <= ST_SNES_WR_WAIT1;
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; end
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_SNES_WR_END; ST_SNES_WR_WAIT2: begin
else STATE <= ST_SNES_WR_WAIT2; ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
end if(ST_MEM_DELAYr == 0) begin
ST_SNES_WR_END: begin STATE <= ST_SNES_WR_END;
STATE <= ST_IDLE;
ROM_WEr <= 1'b1; ROM_WEr <= 1'b1;
snes_wr_cycle <= 1'b0;
end end
ST_MCU_RD_ADDR: begin else STATE <= ST_SNES_WR_WAIT2;
ROM_ADDRr <= MCU_ADDR; end
STATE <= ST_MCU_RD_WAIT; ST_SNES_RD_END, ST_SNES_WR_END: begin
ST_MEM_DELAYr <= ROM_RD_WAIT_MCU; ROM_DOUT_ENr <= 1'b0;
if(MCU_RD_PENDr) begin
STATE <= ST_MCU_RD_ADDR;
end else if(MCU_WR_PENDr) begin
STATE <= ST_MCU_WR_ADDR;
end else STATE <= ST_IDLE;
end
ST_MCU_RD_ADDR: begin
ROM_SAr <= 1'b0;
ST_MEM_DELAYr <= ROM_RD_WAIT_MCU;
STATE <= ST_MCU_RD_WAIT;
end
ST_MCU_RD_WAIT: begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
if(ST_MEM_DELAYr == 0) begin
STATE <= ST_MCU_RD_END;
end end
ST_MCU_RD_WAIT: begin else STATE <= ST_MCU_RD_WAIT;
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; end
if(ST_MEM_DELAYr == 4'h0) begin ST_MCU_RD_END: begin
STATE <= ST_MCU_RD_WAIT2; MCU_DINr <= ROM_ADDRr[0] ? ROM_DATA[7:0] : ROM_DATA[15:8];
ST_MEM_DELAYr <= 4'h2; STATE <= ST_IDLE;
end end
else STATE <= ST_MCU_RD_WAIT;
if(ROM_ADDR0) MCU_DINr <= ROM_DATA[7:0]; ST_MCU_WR_ADDR: begin
else MCU_DINr <= ROM_DATA[15:8]; ROM_DOUTr <= MCU_DOUT;
end ROM_SAr <= 1'b0;
ST_MCU_RD_WAIT2: begin ST_MEM_DELAYr <= ROM_WR_WAIT_MCU;
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; STATE <= ST_MCU_WR_WAIT;
if(ST_MEM_DELAYr == 4'h0) begin ROM_DOUT_ENr <= 1'b1;
STATE <= ST_MCU_RD_END; ROM_WEr <= 1'b0;
end else STATE <= ST_MCU_RD_WAIT2; end
ST_MCU_WR_WAIT: begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
if(ST_MEM_DELAYr == 0) begin
ROM_WEr <= 1'b1;
STATE <= ST_MCU_WR_END;
end end
ST_MCU_RD_END: begin else STATE <= ST_MCU_WR_WAIT;
STATE <= ST_IDLE; end
end ST_MCU_WR_END: begin
ST_MCU_WR_ADDR: begin ROM_DOUT_ENr <= 1'b0;
ROM_ADDRr <= MCU_ADDR; STATE <= ST_IDLE;
STATE <= ST_MCU_WR_WAIT; end
ST_MEM_DELAYr <= ROM_WR_WAIT_MCU; endcase
ROM_DOUTr <= MCU_DOUT;
ROM_WEr <= 1'b0;
end
ST_MCU_WR_WAIT: begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1;
if(ST_MEM_DELAYr == 4'h0) begin
ROM_WEr <= 1'b1;
STATE <= ST_MCU_WR_WAIT2;
ST_MEM_DELAYr <= 4'h2;
end
else STATE <= ST_MCU_WR_WAIT;
end
ST_MCU_WR_WAIT2: begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1;
if(ST_MEM_DELAYr == 4'h0) begin
STATE <= ST_MCU_WR_END;
end else STATE <= ST_MCU_WR_WAIT2;
end
ST_MCU_WR_END: begin
STATE <= ST_IDLE;
end
endcase
end
end end
always @(posedge SYSCLK2) begin always @(posedge SYSCLK2) begin

1
verilog/sd2snes_cx4/cx4.v
View File

@ -334,6 +334,7 @@ always @(posedge CLK) begin
CACHE_ST <= ST_CACHE_START; CACHE_ST <= ST_CACHE_START;
cache_pgmpage <= cx4_mmio_pgmpage; cache_pgmpage <= cx4_mmio_pgmpage;
cache_cachepage <= cx4_mmio_cachepage; cache_cachepage <= cx4_mmio_cachepage;
cx4_busy[BUSY_CACHE] <= 1'b1;
end else if(cpu_cache_en end else if(cpu_cache_en
& (~cachevalid[~cpu_page] & (~cachevalid[~cpu_page]
| |(cachetag[~cpu_page] ^ cpu_p))) begin | |(cachetag[~cpu_page] ^ cpu_p))) begin

338
verilog/sd2snes_cx4/main.v
View File

@ -87,6 +87,9 @@ always @(posedge CLK2) begin
end end
wire [23:0] SNES_ADDR = SNES_ADDR_r[2] & SNES_ADDR_r[1]; wire [23:0] SNES_ADDR = SNES_ADDR_r[2] & SNES_ADDR_r[1];
wire [7:0] CX4_SNES_DATA_IN;
wire [7:0] CX4_SNES_DATA_OUT;
wire [7:0] spi_cmd_data; wire [7:0] spi_cmd_data;
wire [7:0] spi_param_data; wire [7:0] spi_param_data;
wire [7:0] spi_input_data; wire [7:0] spi_input_data;
@ -114,9 +117,6 @@ wire [7:0] MSU_SNES_DATA_OUT;
wire [5:0] msu_status_reset_bits; wire [5:0] msu_status_reset_bits;
wire [5:0] msu_status_set_bits; wire [5:0] msu_status_set_bits;
wire [7:0] CX4_SNES_DATA_IN;
wire [7:0] CX4_SNES_DATA_OUT;
wire [23:0] MAPPED_SNES_ADDR; wire [23:0] MAPPED_SNES_ADDR;
wire ROM_ADDR0; wire ROM_ADDR0;
@ -369,25 +369,28 @@ parameter ST_MCU_WR_WAIT2 = 21'b000001000000000000000;
parameter ST_MCU_WR_END = 21'b000010000000000000000; parameter ST_MCU_WR_END = 21'b000010000000000000000;
parameter ST_CX4_RD_ADDR = 21'b000100000000000000000; parameter ST_CX4_RD_ADDR = 21'b000100000000000000000;
parameter ST_CX4_RD_WAIT = 21'b001000000000000000000; parameter ST_CX4_RD_WAIT = 21'b001000000000000000000;
parameter ST_CX4_RD_WAIT2 = 21'b010000000000000000000; parameter ST_CX4_RD_END = 21'b010000000000000000000;
parameter ST_CX4_RD_END = 21'b100000000000000000000;
parameter ROM_RD_WAIT = 4'h4; parameter ROM_RD_WAIT = 4'h0;
parameter ROM_RD_WAIT_MCU = 4'h6; parameter ROM_RD_WAIT_MCU = 4'h6;
parameter ROM_WR_WAIT = 4'h4;
parameter ROM_WR_WAIT1 = 4'h2; parameter ROM_WR_WAIT1 = 4'h2;
parameter ROM_WR_WAIT2 = 4'h3; parameter ROM_WR_WAIT2 = 4'h1;
parameter ROM_WR_WAIT_MCU = 4'h6; parameter ROM_WR_WAIT_MCU = 4'h5;
parameter ROM_RD_WAIT_CX4 = 4'h6; parameter ROM_RD_WAIT_CX4 = 4'h6;
parameter SNES_DEAD_TIMEOUT = 17'd88000; // 1ms
reg [20:0] STATE; reg [20:0] STATE;
initial STATE = ST_IDLE; initial STATE = ST_IDLE;
reg [7:0] SNES_DINr;
reg [7:0] SNES_DOUTr;
reg [7:0] ROM_DOUTr;
assign MSU_SNES_DATA_IN = SNES_DATA; assign MSU_SNES_DATA_IN = SNES_DATA;
assign CX4_SNES_DATA_IN = SNES_DATA; assign CX4_SNES_DATA_IN = SNES_DATA;
reg [7:0] SNES_DINr;
reg [7:0] ROM_DOUTr;
reg [7:0] r213fr; reg [7:0] r213fr;
reg r213f_forceread; reg r213f_forceread;
reg [2:0] r213f_delay; reg [2:0] r213f_delay;
@ -419,25 +422,61 @@ always @(posedge CLK2) begin
end end
wire IS_CART = IS_ROM | IS_SAVERAM | IS_WRITABLE; wire IS_CART = IS_ROM | IS_SAVERAM | IS_WRITABLE;
wire ASSERT_SNES_ADDR = SNES_CPU_CLK & NEED_SNES_ADDRr & IS_CART & ~cx4_active;
assign ROM_ADDR = (SD_DMA_TO_ROM) ? MCU_ADDR[23:1] : (ASSERT_SNES_ADDR) ? MAPPED_SNES_ADDR[23:1] : ROM_ADDRr[23:1];
assign ROM_ADDR0 = (SD_DMA_TO_ROM) ? MCU_ADDR[0] : (ASSERT_SNES_ADDR) ? MAPPED_SNES_ADDR[0] : ROM_ADDRr[0];
reg ROM_WEr;
initial ROM_WEr = 1'b1;
reg RQ_MCU_RDYr; reg RQ_MCU_RDYr;
initial RQ_MCU_RDYr = 1'b1; initial RQ_MCU_RDYr = 1'b1;
assign MCU_RDY = RQ_MCU_RDYr; assign MCU_RDY = RQ_MCU_RDYr;
reg RQ_CX4_RDYr;
initial RQ_CX4_RDYr = 1'b1;
assign CX4_RDY = RQ_CX4_RDYr;
reg ROM_SAr;
initial ROM_SAr = 1'b1;
wire ROM_SA = ROM_SAr;
reg ROM_CAr;
initial ROM_CAr = 1'b0;
wire ROM_CA = ROM_CAr;
reg [23:0] CX4_ADDRr;
assign ROM_ADDR = (SD_DMA_TO_ROM) ? MCU_ADDR[23:1] : ROM_CA ? CX4_ADDRr[23:1] : ROM_SA ? MAPPED_SNES_ADDR[23:1] : ROM_ADDRr[23:1];
assign ROM_ADDR0 = (SD_DMA_TO_ROM) ? MCU_ADDR[0] : ROM_CA ? CX4_ADDRr[0] : ROM_SA ? MAPPED_SNES_ADDR[0] : ROM_ADDRr[0];
reg ROM_WEr;
initial ROM_WEr = 1'b1;
reg ROM_DOUT_ENr;
initial ROM_DOUT_ENr = 1'b0;
reg[17:0] SNES_DEAD_CNTr;
initial SNES_DEAD_CNTr = 0;
always @(posedge CLK2) begin
if(cx4_active) begin
if(CX4_RRQ) begin
CX4_RD_PENDr <= 1'b1;
RQ_CX4_RDYr <= 1'b0;
CX4_ADDRr <= CX4_ADDR;
end else if(STATE == ST_CX4_RD_END) begin
CX4_RD_PENDr <= 1'b0;
RQ_CX4_RDYr <= 1'b1;
end
end else begin
CX4_RD_PENDr <= 1'b0;
RQ_CX4_RDYr <= 1'b1;
end
end
always @(posedge CLK2) begin always @(posedge CLK2) begin
if(MCU_RRQ) begin if(MCU_RRQ) begin
MCU_RD_PENDr <= 1'b1; MCU_RD_PENDr <= 1'b1;
RQ_MCU_RDYr <= 1'b0; RQ_MCU_RDYr <= 1'b0;
ROM_ADDRr <= MCU_ADDR;
end else if(MCU_WRQ) begin end else if(MCU_WRQ) begin
MCU_WR_PENDr <= 1'b1; MCU_WR_PENDr <= 1'b1;
RQ_MCU_RDYr <= 1'b0; RQ_MCU_RDYr <= 1'b0;
ROM_ADDRr <= MCU_ADDR;
end else if(STATE & (ST_MCU_RD_END | ST_MCU_WR_END)) begin end else if(STATE & (ST_MCU_RD_END | ST_MCU_WR_END)) begin
MCU_RD_PENDr <= 1'b0; MCU_RD_PENDr <= 1'b0;
MCU_WR_PENDr <= 1'b0; MCU_WR_PENDr <= 1'b0;
@ -445,151 +484,138 @@ always @(posedge CLK2) begin
end end
end end
reg RQ_CX4_RDYr;
initial RQ_CX4_RDYr = 1'b1;
assign CX4_RDY = RQ_CX4_RDYr;
always @(posedge CLK2) begin always @(posedge CLK2) begin
if(CX4_RRQ) begin if(~SNES_CPU_CLK) SNES_DEAD_CNTr <= SNES_DEAD_CNTr + 1;
CX4_RD_PENDr <= 1'b1; else SNES_DEAD_CNTr <= 17'h0;
RQ_CX4_RDYr <= 1'b0;
end else if(STATE == ST_CX4_RD_WAIT && ST_MEM_DELAYr == 4'h0) begin
CX4_RD_PENDr <= 1'b0;
RQ_CX4_RDYr <= 1'b1;
end
end end
reg snes_wr_cycle; always @(posedge CLK2) begin
if(SNES_DEAD_CNTr > SNES_DEAD_TIMEOUT) SNES_DEADr <= 1'b1;
else if(SNES_CPU_CLK) SNES_DEADr <= 1'b0;
end
always @(posedge CLK2) begin always @(posedge CLK2) begin
if(SNES_cycle_start & IS_CART & ~cx4_active) begin if(SNES_DEADr & SNES_CPU_CLK) STATE <= ST_IDLE; // interrupt+restart an ongoing MCU access when the SNES comes alive
STATE <= ST_SNES_RD_ADDR; else
end else if(SNES_WR_start & IS_CART & ~cx4_active) begin case(STATE)
STATE <= ST_SNES_WR_ADDR; ST_IDLE: begin
end else begin ROM_SAr <= 1'b1;
case(STATE) ROM_CAr <= 1'b0;
ST_IDLE: begin ROM_DOUT_ENr <= 1'b0;
ROM_ADDRr <= MAPPED_SNES_ADDR; if(cx4_active) begin
if(CX4_RD_PENDr) begin if(CX4_RD_PENDr) STATE <= ST_CX4_RD_ADDR;
STATE <= ST_CX4_RD_WAIT; end else if(SNES_cycle_start & ~SNES_WRITE) begin
ROM_ADDRr <= CX4_ADDR; STATE <= ST_SNES_WR_ADDR;
ST_MEM_DELAYr <= ROM_RD_WAIT_CX4; if(IS_SAVERAM | IS_WRITABLE) begin
end else if(~cx4_active && ~ASSERT_SNES_ADDR) begin ROM_WEr <= 1'b0;
if(MCU_RD_PENDr) STATE <= ST_MCU_RD_ADDR; ROM_DOUT_ENr <= 1'b1;
else if(MCU_WR_PENDr) STATE <= ST_MCU_WR_ADDR;
else STATE <= ST_IDLE;
end end
else STATE <= ST_IDLE; end else if(SNES_cycle_start) begin
end // STATE <= ST_SNES_RD_ADDR;
ST_SNES_RD_ADDR: begin STATE <= ST_SNES_RD_END;
STATE <= ST_SNES_RD_WAIT; SNES_DOUTr <= (ROM_ADDR0 ? ROM_DATA[7:0] : ROM_DATA[15:8]);
ST_MEM_DELAYr <= ROM_RD_WAIT; end else if(SNES_DEADr & MCU_RD_PENDr) begin
end STATE <= ST_MCU_RD_ADDR;
ST_SNES_RD_WAIT: begin end else if(SNES_DEADr & MCU_WR_PENDr) begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; STATE <= ST_MCU_WR_ADDR;
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_SNES_RD_END; end
else STATE <= ST_SNES_RD_WAIT; end
if(ROM_ADDR0) SNES_DINr <= ROM_DATA[7:0]; ST_SNES_RD_ADDR: begin
else SNES_DINr <= ROM_DATA[15:8]; ST_MEM_DELAYr <= ROM_RD_WAIT;
end STATE <= ST_SNES_RD_WAIT;
ST_SNES_RD_END: begin end
STATE <= ST_IDLE; ST_SNES_RD_WAIT: begin
if(ROM_ADDR0) SNES_DINr <= ROM_DATA[7:0]; ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
else SNES_DINr <= ROM_DATA[15:8]; // if(ST_MEM_DELAYr == 0) begin
end // end
ST_SNES_WR_ADDR: begin // else STATE <= ST_SNES_RD_WAIT;
ROM_WEr <= (!IS_WRITABLE); end
snes_wr_cycle <= 1'b1;
STATE <= ST_SNES_WR_WAIT1; ST_SNES_WR_ADDR: begin
ST_MEM_DELAYr <= ROM_WR_WAIT1; ST_MEM_DELAYr <= ROM_WR_WAIT1;
end STATE <= ST_SNES_WR_WAIT1;
ST_SNES_WR_WAIT1: begin end
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; ST_SNES_WR_WAIT1: begin
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_SNES_WR_DATA; ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
else STATE <= ST_SNES_WR_WAIT1; if(ST_MEM_DELAYr == 0) begin
end ST_MEM_DELAYr <= ROM_WR_WAIT2;
ST_SNES_WR_DATA: begin
ROM_DOUTr <= SNES_DATA;
ST_MEM_DELAYr <= ROM_WR_WAIT2;
STATE <= ST_SNES_WR_WAIT2; STATE <= ST_SNES_WR_WAIT2;
end ROM_DOUTr <= SNES_DATA;
ST_SNES_WR_WAIT2: begin end
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; else STATE <= ST_SNES_WR_WAIT1;
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_SNES_WR_END; end
else STATE <= ST_SNES_WR_WAIT2; ST_SNES_WR_WAIT2: begin
end ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
ST_SNES_WR_END: begin if(ST_MEM_DELAYr == 0) begin
STATE <= ST_IDLE; STATE <= ST_SNES_WR_END;
ROM_WEr <= 1'b1; ROM_WEr <= 1'b1;
snes_wr_cycle <= 1'b0; end
end else STATE <= ST_SNES_WR_WAIT2;
ST_MCU_RD_ADDR: begin end
ROM_ADDRr <= MCU_ADDR; ST_SNES_RD_END, ST_SNES_WR_END: begin
STATE <= ST_MCU_RD_WAIT; ROM_DOUT_ENr <= 1'b0;
ST_MEM_DELAYr <= ROM_RD_WAIT_MCU; if(MCU_RD_PENDr) begin
end STATE <= ST_MCU_RD_ADDR;
ST_MCU_RD_WAIT: begin end else if(MCU_WR_PENDr) begin
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; STATE <= ST_MCU_WR_ADDR;
if(ST_MEM_DELAYr == 4'h0) begin end else STATE <= ST_IDLE;
STATE <= ST_MCU_RD_WAIT2; end
ST_MEM_DELAYr <= 4'h2; ST_MCU_RD_ADDR: begin
if(ROM_ADDR0) MCU_DINr <= ROM_DATA[7:0]; ROM_SAr <= 1'b0;
else MCU_DINr <= ROM_DATA[15:8]; ST_MEM_DELAYr <= ROM_RD_WAIT_MCU;
end STATE <= ST_MCU_RD_WAIT;
else STATE <= ST_MCU_RD_WAIT; end
end ST_MCU_RD_WAIT: begin
ST_MCU_RD_WAIT2: begin ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; if(ST_MEM_DELAYr == 0) begin
if(ST_MEM_DELAYr == 4'h0) begin STATE <= ST_MCU_RD_END;
STATE <= ST_MCU_RD_END; end
end else STATE <= ST_MCU_RD_WAIT2; else STATE <= ST_MCU_RD_WAIT;
end end
ST_MCU_RD_END: begin ST_MCU_RD_END: begin
STATE <= ST_IDLE; MCU_DINr <= ROM_ADDRr[0] ? ROM_DATA[7:0] : ROM_DATA[15:8];
end STATE <= ST_IDLE;
ST_MCU_WR_ADDR: begin end
ROM_ADDRr <= MCU_ADDR;
STATE <= ST_MCU_WR_WAIT; ST_MCU_WR_ADDR: begin
ST_MEM_DELAYr <= ROM_WR_WAIT_MCU; ROM_DOUTr <= MCU_DOUT;
ROM_DOUTr <= MCU_DOUT; ROM_SAr <= 1'b0;
ROM_WEr <= 1'b0; ST_MEM_DELAYr <= ROM_WR_WAIT_MCU;
end STATE <= ST_MCU_WR_WAIT;
ST_MCU_WR_WAIT: begin ROM_DOUT_ENr <= 1'b1;
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; ROM_WEr <= 1'b0;
if(ST_MEM_DELAYr == 4'h0) begin end
ROM_WEr <= 1'b1; ST_MCU_WR_WAIT: begin
STATE <= ST_MCU_WR_WAIT2; ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
ST_MEM_DELAYr <= 4'h2; if(ST_MEM_DELAYr == 0) begin
end ROM_WEr <= 1'b1;
else STATE <= ST_MCU_WR_WAIT; STATE <= ST_MCU_WR_END;
end end
ST_MCU_WR_WAIT2: begin else STATE <= ST_MCU_WR_WAIT;
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; end
if(ST_MEM_DELAYr == 4'h0) begin ST_MCU_WR_END: begin
STATE <= ST_MCU_WR_END; ROM_DOUT_ENr <= 1'b0;
end else STATE <= ST_MCU_WR_WAIT2; STATE <= ST_IDLE;
end end
ST_MCU_WR_END: begin ST_CX4_RD_ADDR: begin
STATE <= ST_IDLE; ROM_CAr <= 1'b1;
end ST_MEM_DELAYr <= ROM_RD_WAIT_CX4;
STATE <= ST_CX4_RD_WAIT;
ST_CX4_RD_ADDR: begin end
ROM_ADDRr <= CX4_ADDR; ST_CX4_RD_WAIT: begin
STATE <= ST_CX4_RD_WAIT; ST_MEM_DELAYr <= ST_MEM_DELAYr - 1;
ST_MEM_DELAYr <= ROM_RD_WAIT_CX4; if(ST_MEM_DELAYr == 0) begin
end STATE <= ST_CX4_RD_END;
ST_CX4_RD_WAIT: begin end
ST_MEM_DELAYr <= ST_MEM_DELAYr - 4'h1; else STATE <= ST_CX4_RD_WAIT;
if(ST_MEM_DELAYr == 4'h0) STATE <= ST_IDLE; end
else STATE <= ST_CX4_RD_WAIT; ST_CX4_RD_END: begin
if(ROM_ADDR0) CX4_DINr <= ROM_DATA[7:0]; ROM_CAr <= 1'b0;
else CX4_DINr <= ROM_DATA[15:8]; CX4_DINr <= CX4_ADDRr[0] ? ROM_DATA[7:0] : ROM_DATA[15:8];
end STATE <= ST_IDLE;
ST_CX4_RD_END: begin end
STATE <= ST_IDLE;
end endcase
endcase
end
end end
always @(posedge SYSCLK2) begin always @(posedge SYSCLK2) begin

30
verilog/sd2sneslite/main.v
View File

@ -35,6 +35,10 @@ module main(
output SNES_DATABUS_DIR, output SNES_DATABUS_DIR,
input SNES_SYSCLK, input SNES_SYSCLK,
input [7:0] SNES_PA,
input SNES_PARD,
input SNES_PAWR,
/* SRAM signals */ /* SRAM signals */
/* Bus 1: PSRAM, 128Mbit, 16bit, 70ns */ /* Bus 1: PSRAM, 128Mbit, 16bit, 70ns */
inout [15:0] ROM_DATA, inout [15:0] ROM_DATA,
@ -93,8 +97,6 @@ wire [7:0] spi_input_data;
wire [31:0] spi_byte_cnt; wire [31:0] spi_byte_cnt;
wire [2:0] spi_bit_cnt; wire [2:0] spi_bit_cnt;
wire [23:0] MCU_ADDR; wire [23:0] MCU_ADDR;
wire [7:0] mcu_data_in;
wire [7:0] mcu_data_out;
wire [23:0] SAVERAM_MASK; wire [23:0] SAVERAM_MASK;
wire [23:0] ROM_MASK; wire [23:0] ROM_MASK;
@ -125,7 +127,6 @@ mcu_cmd snes_mcu_cmd(
.param_ready(spi_param_ready), .param_ready(spi_param_ready),
.cmd_data(spi_cmd_data), .cmd_data(spi_cmd_data),
.param_data(spi_param_data), .param_data(spi_param_data),
.mcu_write(MCU_WRITE),
.mcu_data_in(MCU_DINr), .mcu_data_in(MCU_DINr),
.mcu_data_out(MCU_DOUT), .mcu_data_out(MCU_DOUT),
.spi_byte_cnt(spi_byte_cnt), .spi_byte_cnt(spi_byte_cnt),
@ -140,7 +141,6 @@ mcu_cmd snes_mcu_cmd(
); );
wire [7:0] DCM_STATUS; wire [7:0] DCM_STATUS;
// dcm1: dfs 4x // dcm1: dfs 4x
my_dcm snes_dcm( my_dcm snes_dcm(
.CLKIN(CLKIN), .CLKIN(CLKIN),
@ -194,11 +194,6 @@ address snes_addr(
.ROM_MASK(ROM_MASK) .ROM_MASK(ROM_MASK)
); );
wire SNES_READ_CYCLEw;
wire SNES_WRITE_CYCLEw;
wire MCU_READ_CYCLEw;
wire MCU_WRITE_CYCLEw;
parameter MODE_SNES = 1'b0; parameter MODE_SNES = 1'b0;
parameter MODE_MCU = 1'b1; parameter MODE_MCU = 1'b1;
@ -220,23 +215,24 @@ parameter ST_MCU_WR_WAIT = 18'b000100000000000000;
parameter ST_MCU_WR_WAIT2 = 18'b001000000000000000; parameter ST_MCU_WR_WAIT2 = 18'b001000000000000000;
parameter ST_MCU_WR_END = 18'b010000000000000000; parameter ST_MCU_WR_END = 18'b010000000000000000;
parameter ROM_RD_WAIT = 4'h4; parameter ROM_RD_WAIT = 4'h0;
parameter ROM_RD_WAIT_MCU = 4'h6; parameter ROM_RD_WAIT_MCU = 4'h6;
parameter ROM_WR_WAIT = 4'h4;
parameter ROM_WR_WAIT1 = 4'h2; parameter ROM_WR_WAIT1 = 4'h2;
parameter ROM_WR_WAIT2 = 4'h3; parameter ROM_WR_WAIT2 = 4'h1;
parameter ROM_WR_WAIT_MCU = 4'h6; parameter ROM_WR_WAIT_MCU = 4'h5;
parameter SNES_DEAD_TIMEOUT = 17'd88000; // 1ms
reg [17:0] STATE; reg [17:0] STATE;
initial STATE = ST_IDLE; initial STATE = ST_IDLE;
reg [1:0] CYCLE_RESET;
reg ROM_WE_MASK;
reg ROM_OE_MASK;
reg [7:0] SNES_DINr; reg [7:0] SNES_DINr;
reg [7:0] SNES_DOUTr;
reg [7:0] ROM_DOUTr; reg [7:0] ROM_DOUTr;
assign SNES_DATA = (!SNES_READ) ? SNES_DINr : 8'bZ; assign SNES_DATA = ~SNES_READ ? SNES_DOUTr
: 8'bZ;
reg [3:0] ST_MEM_DELAYr; reg [3:0] ST_MEM_DELAYr;
reg MCU_RD_PENDr; reg MCU_RD_PENDr;