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// 
// OpenSPARC T2 Processor File: ncu_niu_chkr.v
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module ncu_niu_chkr(
			iol2clk,
                        ncu_niu_vld,            // From c2i of c2i.v
                        ncu_niu_data,           // From c2i of c2i.v
                        niu_ncu_data,           // To i2c of i2c.v
                        niu_ncu_vld,            // To i2c of i2c.v
                        niu_ncu_stall,          // To c2i of c2i.v
                        ncu_niu_stall           // From i2c of i2c.v
);

input                   iol2clk;

input                   ncu_niu_vld;            // From c2i of c2i.v
input [31:0]            ncu_niu_data;           // From c2i of c2i.v
input                   niu_ncu_stall;          // To c2i of c2i.v

input [31:0]            niu_ncu_data;           // To i2c of i2c.v
input                   niu_ncu_vld;            // To i2c of i2c.v
input                   ncu_niu_stall;          // From i2c of i2c.v

wire por_reset_l = !`NCU.tcu_aclk;

// 0in set_clock  -default   iol2clk  -module ncu_niu_chkr
// 0in default_reset `NCU.tcu_aclk -module ncu_niu_chkr 
`ifdef X_GUARD
// 0in known_driven -var ncu_niu_stall   -name ncu_niu_stall_x_guard -active por_reset_l  
// 0in known_driven -var niu_ncu_vld     -name niu_ncu_vld_x_guard   -active por_reset_l 
// 0in known_driven -var niu_ncu_stall   -name niu_ncu_stall_x_guard -active por_reset_l 
// 0in known_driven -var ncu_niu_vld     -name ncu_niu_vld_x_guard   -active por_reset_l 
`endif


//*********************************
// make sure vald and stall do not active to long
//*********************************

reg [9:0] niu_ncu_vld_cnt;
reg [9:0] niu_ncu_stall_cnt;
reg [9:0] ncu_niu_vld_cnt;
reg [9:0] ncu_niu_stall_cnt;

/* 0in range
        -var niu_ncu_vld_cnt
        -min 0
        -max 4
*/

/* 0in range
        -var niu_ncu_stall_cnt
        -min 0
        -max 1000
*/

/* 0in range
        -var ncu_niu_vld_cnt
        -min 0
        -max 4
*/

/* 0in range
        -var ncu_niu_stall_cnt
        -min 0
        -max 1000

*/

reg ncu_niu_stall_del;
reg niu_ncu_stall_del;

always @(posedge iol2clk) begin
  if (niu_ncu_vld && !ncu_niu_stall_del) begin
	niu_ncu_vld_cnt = niu_ncu_vld_cnt + 1;
  end
  else if (!niu_ncu_vld) begin
	niu_ncu_vld_cnt = 0;
  end

  if (niu_ncu_stall_del) begin 
	niu_ncu_stall_cnt = niu_ncu_stall_cnt + 1;
  end else begin
	niu_ncu_stall_cnt = 0;
  end
  

  if (ncu_niu_vld && !niu_ncu_stall_del) begin
	ncu_niu_vld_cnt = ncu_niu_vld_cnt + 1;
  end
  else if (!ncu_niu_vld) begin
	ncu_niu_vld_cnt = 0;
  end

  if (ncu_niu_stall_del) begin
    ncu_niu_stall_cnt = ncu_niu_stall_cnt + 1;
  end
  else begin
	ncu_niu_stall_cnt = 0;
  end 

  ncu_niu_stall_del = ncu_niu_stall;
  niu_ncu_stall_del = niu_ncu_stall;
end



endmodule