// ========== Copyright Header Begin ==========================================
// 
// OpenSPARC T2 Processor File: ncu_io_chkr.v
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module ncu_io_chkr(
			iol2clk,
                        ncu_io_vld,            // From c2i of c2i.v
                        ncu_io_data,           // From c2i of c2i.v
                        io_ncu_data,           // To i2c of i2c.v
                        io_ncu_vld,            // To i2c of i2c.v
                        io_ncu_stall,          // To c2i of c2i.v
                        ncu_io_stall          // From i2c of i2c.v

);

input                   iol2clk;

input                   ncu_io_vld;            // From c2i of c2i.v
input [3:0]             ncu_io_data;           // From c2i of c2i.v
input                   io_ncu_stall;          // To c2i of c2i.v

input [3:0]             io_ncu_data;           // To i2c of i2c.v
input                   io_ncu_vld;            // To i2c of i2c.v
input                   ncu_io_stall;          // From i2c of i2c.v

wire por_reset_l = ~`NCU.tcu_aclk;

// 0in set_clock  -default   iol2clk  -module ncu_io_chkr
// 0in default_reset `NCU.tcu_aclk -module ncu_io_chkr

`ifdef X_GUARD
// 0in known_driven -var ncu_io_stall   -name ncu_io_stall_x_guard -active por_reset_l
// 0in known_driven -var io_ncu_vld     -name io_ncu_vld_x_guard   -active por_reset_l
// 0in known_driven -var io_ncu_stall   -name io_ncu_stall_x_guard -active por_reset_l
// 0in known_driven -var ncu_io_vld     -name ncu_io_vld_x_guard   -active por_reset_l
`endif

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

reg [9:0] io_ncu_vld_cnt;
reg [9:0] io_ncu_stall_cnt;
reg [9:0] ncu_io_vld_cnt;
reg [9:0] ncu_io_stall_cnt;

/* 0in range
        -var io_ncu_vld_cnt
        -min 0
        -max 32
*/

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

/* 0in range
        -var ncu_io_vld_cnt
        -min 0
        -max 32
*/

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

*/

reg ncu_io_stall_del;
reg io_ncu_stall_del;

always @(posedge iol2clk) begin
  if (io_ncu_vld && !ncu_io_stall_del) begin
        io_ncu_vld_cnt = io_ncu_vld_cnt + 1;
  end
  else if (!io_ncu_vld) begin
        io_ncu_vld_cnt = 0;
  end

  if (io_ncu_stall_del) begin
        io_ncu_stall_cnt = io_ncu_stall_cnt + 1;
  end else begin
        io_ncu_stall_cnt = 0;
  end


  if (ncu_io_vld && !io_ncu_stall_del) begin
	ncu_io_vld_cnt = ncu_io_vld_cnt + 1;
  end
  else if (!ncu_io_vld) begin
        ncu_io_vld_cnt = 0;
  end

  if (ncu_io_stall_del) begin 
	ncu_io_stall_cnt = ncu_io_stall_cnt + 1;
  end
  else begin
        ncu_io_stall_cnt = 0;
  end

  ncu_io_stall_del <= ncu_io_stall;
  io_ncu_stall_del <= io_ncu_stall;
end



endmodule