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-rw-r--r--rtl/src/verilog/novena_clkmgr.v162
1 files changed, 81 insertions, 81 deletions
diff --git a/rtl/src/verilog/novena_clkmgr.v b/rtl/src/verilog/novena_clkmgr.v
index 2f8c02f..5713383 100644
--- a/rtl/src/verilog/novena_clkmgr.v
+++ b/rtl/src/verilog/novena_clkmgr.v
@@ -1,100 +1,100 @@
-`timescale 1ns / 1ps
-
-module novena_clkmgr
- (
+`timescale 1ns / 1ps
+
+module novena_clkmgr
+ (
gclk_p, gclk_n,
reset_mcu_b,
- sys_clk, sys_rst,
- bclk_in, bclk_out
- );
-
- //
- // Ports
- //
- input wire gclk_p; // signal from clock pins
- input wire gclk_n; //
-
- input wire reset_mcu_b; // cpu reset (async)
-
- output wire sys_clk; // buffered system clock output
- output wire sys_rst; // system reset output (sync)
-
- input wire bclk_in; // signal from clock pin
- output wire bclk_out; // buffered clock output
-
-
- //
- // IBUFGDS
- //
- (* BUFFER_TYPE="NONE" *)
- wire gclk;
-
+ sys_clk, sys_rst,
+ bclk_in, bclk_out
+ );
+
+ //
+ // Ports
+ //
+ input wire gclk_p; // signal from clock pins
+ input wire gclk_n; //
+
+ input wire reset_mcu_b; // cpu reset (async)
+
+ output wire sys_clk; // buffered system clock output
+ output wire sys_rst; // system reset output (sync)
+
+ input wire bclk_in; // signal from clock pin
+ output wire bclk_out; // buffered clock output
+
+
+ //
+ // IBUFGDS
+ //
+ (* BUFFER_TYPE="NONE" *)
+ wire gclk;
+
IBUFGDS IBUFGDS_gclk
(
.I (gclk_p),
.IB (gclk_n),
.O (gclk)
- );
-
-
- //
- // DCM
- //
- wire dcm_reset; // dcm reset
- wire dcm_locked; // output clock valid
- wire gclk_missing; // no input clock
-
- clkmgr_dcm dcm
- (
- .CLK_IN1 (gclk),
- .RESET (dcm_reset),
- .INPUT_CLK_STOPPED (gclk_missing),
-
- .CLK_OUT1 (sys_clk),
- .CLK_VALID (dcm_locked)
- );
-
-
+ );
+
+
+ //
+ // DCM
+ //
+ wire dcm_reset; // dcm reset
+ wire dcm_locked; // output clock valid
+ wire gclk_missing; // no input clock
+
+ clkmgr_dcm dcm
+ (
+ .CLK_IN1 (gclk),
+ .RESET (dcm_reset),
+ .INPUT_CLK_STOPPED (gclk_missing),
+
+ .CLK_OUT1 (sys_clk),
+ .CLK_VALID (dcm_locked)
+ );
+
+
//
// DCM Reset Logic
- //
-
- /* DCM should be reset on power-up, when input clock is stopped or when the CPU gets reset. */
-
- reg [15: 0] dcm_rst_shreg = {16{1'b1}}; // 16-bit shift register
-
+ //
+
+ /* DCM should be reset on power-up, when input clock is stopped or when the CPU gets reset. */
+
+ reg [15: 0] dcm_rst_shreg = {16{1'b1}}; // 16-bit shift register
+
always @(posedge gclk or negedge reset_mcu_b or posedge gclk_missing)
//
if ((reset_mcu_b == 1'b0) || (gclk_missing == 1'b1)) dcm_rst_shreg <= {16{1'b1}};
else dcm_rst_shreg <= {dcm_rst_shreg[14:0], 1'b0};
-
- assign dcm_reset = dcm_rst_shreg[15];
-
-
+
+ assign dcm_reset = dcm_rst_shreg[15];
+
+
//
// System Reset Logic
- //
-
- /* System reset is asserted for 16 cycles whenever DCM aquires lock. */
-
+ //
+
+ /* System reset is asserted for 16 cycles whenever DCM aquires lock. */
+
reg [15: 0] sys_rst_shreg = {16{1'b1}}; // 16-bit shift register
-
+
always @(posedge sys_clk or negedge reset_mcu_b or posedge gclk_missing or negedge dcm_locked)
//
if ((reset_mcu_b == 1'b0) || (gclk_missing == 1'b1) || (dcm_locked == 1'b0)) sys_rst_shreg <= {16{1'b1}};
- else if (dcm_locked == 1'b1) sys_rst_shreg <= {sys_rst_shreg[14:0], 1'b0};
-
- assign sys_rst = sys_rst_shreg[15];
-
-
- //
- // BCLK BUFG
- //
- BUFG BUFG_BCLK
- (
- .I (bclk_in),
- .O (bclk_out)
- );
-
-
-endmodule
+ else if (dcm_locked == 1'b1) sys_rst_shreg <= {sys_rst_shreg[14:0], 1'b0};
+
+ assign sys_rst = sys_rst_shreg[15];
+
+
+ //
+ // BCLK BUFG
+ //
+ BUFG BUFG_BCLK
+ (
+ .I (bclk_in),
+ .O (bclk_out)
+ );
+
+
+endmodule