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Diffstat (limited to 'misc/ddrsdram/src/mt46v16m16.vhd')
| -rw-r--r-- | misc/ddrsdram/src/mt46v16m16.vhd | 1320 |
1 files changed, 1320 insertions, 0 deletions
diff --git a/misc/ddrsdram/src/mt46v16m16.vhd b/misc/ddrsdram/src/mt46v16m16.vhd new file mode 100644 index 0000000..356bb28 --- /dev/null +++ b/misc/ddrsdram/src/mt46v16m16.vhd @@ -0,0 +1,1320 @@ +----------------------------------------------------------------------------------------- +-- +-- File Name: MT46V16M16.VHD +-- Version: 2.1 +-- Date: January 14th, 2002 +-- Model: Behavioral +-- Simulator: NCDesktop - http://www.cadence.com +-- ModelSim PE - http://www.model.com +-- +-- Dependencies: None +-- +-- Author: Son P. Huynh +-- Email: sphuynh@micron.com +-- Phone: (208) 368-3825 +-- Company: Micron Technology, Inc. +-- Part Number: MT46V16M16 (4 Mb x 16 x 4 Banks) +-- +-- Description: Micron 256 Mb SDRAM DDR (Double Data Rate) +-- +-- Limitation: Doesn't model internal refresh counter +-- +-- Note: +-- +-- Disclaimer: THESE DESIGNS ARE PROVIDED "AS IS" WITH NO WARRANTY +-- WHATSOEVER AND MICRON SPECIFICALLY DISCLAIMS ANY +-- IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR +-- A PARTICULAR PURPOSE, OR AGAINST INFRINGEMENT. +-- +-- Copyright (c) 1998 Micron Semiconductor Products, Inc. +-- All rights researved +-- +-- Rev Author Date Changes +-- --- ---------------------------- ---------- ------------------------------------- +-- 2.1 Son P. Huynh 01/14/2002 - Fix Burst_counter +-- Micron Technology, Inc. +-- +-- 2.0 Son P. Huynh 11/08/2001 - Second release +-- Micron Technology, Inc. - Rewrote and remove SHARED VARIABLE +-- +----------------------------------------------------------------------------------------- + +LIBRARY IEEE; + USE IEEE.STD_LOGIC_1164.ALL; + USE IEEE.STD_LOGIC_UNSIGNED.ALL; + USE IEEE.STD_LOGIC_ARITH.ALL; + +ENTITY MT46V16M16 IS + GENERIC ( -- Timing for -75Z CL2 + tCK : TIME := 7.500 ns; + tCH : TIME := 3.375 ns; -- 0.45*tCK + tCL : TIME := 3.375 ns; -- 0.45*tCK + tDH : TIME := 0.500 ns; + tDS : TIME := 0.500 ns; + tIH : TIME := 0.900 ns; + tIS : TIME := 0.900 ns; + tMRD : TIME := 15.000 ns; + tRAS : TIME := 40.000 ns; + tRAP : TIME := 20.000 ns; + tRC : TIME := 65.000 ns; + tRFC : TIME := 75.000 ns; + tRCD : TIME := 20.000 ns; + tRP : TIME := 20.000 ns; + tRRD : TIME := 15.000 ns; + tWR : TIME := 15.000 ns; + addr_bits : INTEGER := 13; + data_bits : INTEGER := 16; + cols_bits : INTEGER := 9 + ); + PORT ( + Dq : INOUT STD_LOGIC_VECTOR (data_bits - 1 DOWNTO 0) := (OTHERS => 'Z'); + Dqs : INOUT STD_LOGIC_VECTOR (1 DOWNTO 0) := "ZZ"; + Addr : IN STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0); + Ba : IN STD_LOGIC_VECTOR (1 DOWNTO 0); + Clk : IN STD_LOGIC; + Clk_n : IN STD_LOGIC; + Cke : IN STD_LOGIC; + Cs_n : IN STD_LOGIC; + Ras_n : IN STD_LOGIC; + Cas_n : IN STD_LOGIC; + We_n : IN STD_LOGIC; + Dm : IN STD_LOGIC_VECTOR (1 DOWNTO 0) + ); +END MT46V16M16; + +ARCHITECTURE behave OF MT46V16M16 IS + -- Array for Read pipeline + TYPE Array_Read_cmnd IS ARRAY (8 DOWNTO 0) OF STD_LOGIC; + TYPE Array_Read_bank IS ARRAY (8 DOWNTO 0) OF STD_LOGIC_VECTOR (1 DOWNTO 0); + TYPE Array_Read_cols IS ARRAY (8 DOWNTO 0) OF STD_LOGIC_VECTOR (cols_bits - 1 DOWNTO 0); + + -- Array for Write pipeline + TYPE Array_Write_cmnd IS ARRAY (2 DOWNTO 0) OF STD_LOGIC; + TYPE Array_Write_bank IS ARRAY (2 DOWNTO 0) OF STD_LOGIC_VECTOR (1 DOWNTO 0); + TYPE Array_Write_cols IS ARRAY (2 DOWNTO 0) OF STD_LOGIC_VECTOR (cols_bits - 1 DOWNTO 0); + + -- Array for Auto Precharge + TYPE Array_Read_precharge IS ARRAY (3 DOWNTO 0) OF STD_LOGIC; + TYPE Array_Write_precharge IS ARRAY (3 DOWNTO 0) OF STD_LOGIC; + TYPE Array_Count_precharge IS ARRAY (3 DOWNTO 0) OF INTEGER; + + -- Array for Manual Precharge + TYPE Array_A10_precharge IS ARRAY (8 DOWNTO 0) OF STD_LOGIC; + TYPE Array_Bank_precharge IS ARRAY (8 DOWNTO 0) OF STD_LOGIC_VECTOR (1 DOWNTO 0); + TYPE Array_Cmnd_precharge IS ARRAY (8 DOWNTO 0) OF STD_LOGIC; + + -- Array for Burst Terminate + TYPE Array_Cmnd_bst IS ARRAY (8 DOWNTO 0) OF STD_LOGIC; + + -- Array for Memory Access + TYPE Array_ram_type IS ARRAY (2**cols_bits - 1 DOWNTO 0) OF STD_LOGIC_VECTOR (data_bits - 1 DOWNTO 0); + TYPE Array_ram_pntr IS ACCESS Array_ram_type; + TYPE Array_ram_stor IS ARRAY (2**addr_bits - 1 DOWNTO 0) OF Array_ram_pntr; + + -- Data pair + SIGNAL Dq_pair : STD_LOGIC_VECTOR (2 * data_bits - 1 DOWNTO 0); + SIGNAL Dm_pair : STD_LOGIC_VECTOR (3 DOWNTO 0); + + -- Mode Register + SIGNAL Mode_reg : STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0) := (OTHERS => '0'); + + -- Command Decode Variables + SIGNAL Active_enable, Aref_enable, Burst_term, Ext_mode_enable : STD_LOGIC := '0'; + SIGNAL Mode_reg_enable, Prech_enable, Read_enable, Write_enable : STD_LOGIC := '0'; + + -- Burst Length Decode Variables + SIGNAL Burst_length_2, Burst_length_4, Burst_length_8, Burst_length_f : STD_LOGIC := '0'; + + -- Cas Latency Decode Variables + SIGNAL Cas_latency_15, Cas_latency_2, Cas_latency_25, Cas_latency_3, Cas_latency_4 : STD_LOGIC := '0'; + + -- Internal Control Signals + SIGNAL Cs_in, Ras_in, Cas_in, We_in : STD_LOGIC := '0'; + + -- System Clock + SIGNAL Sys_clk : STD_LOGIC := '0'; + + -- Dqs buffer + SIGNAL Dqs_out : STD_LOGIC_VECTOR (1 DOWNTO 0) := "ZZ"; + +BEGIN + -- Strip the strength + Cs_in <= To_X01 (Cs_n); + Ras_in <= To_X01 (Ras_n); + Cas_in <= To_X01 (Cas_n); + We_in <= To_X01 (We_n); + + -- Commands Decode + Active_enable <= NOT(Cs_in) AND NOT(Ras_in) AND Cas_in AND We_in; + Aref_enable <= NOT(Cs_in) AND NOT(Ras_in) AND NOT(Cas_in) AND We_in; + Burst_term <= NOT(Cs_in) AND Ras_in AND Cas_in AND NOT(We_in); + Ext_mode_enable <= NOT(Cs_in) AND NOT(Ras_in) AND NOT(Cas_in) AND NOT(We_in) AND Ba(0) AND NOT(Ba(1)); + Mode_reg_enable <= NOT(Cs_in) AND NOT(Ras_in) AND NOT(Cas_in) AND NOT(We_in) AND NOT(Ba(0)) AND NOT(Ba(1)); + Prech_enable <= NOT(Cs_in) AND NOT(Ras_in) AND Cas_in AND NOT(We_in); + Read_enable <= NOT(Cs_in) AND Ras_in AND NOT(Cas_in) AND We_in; + Write_enable <= NOT(Cs_in) AND Ras_in AND NOT(Cas_in) AND NOT(We_in); + + -- Burst Length Decode + Burst_length_2 <= NOT(Mode_reg(2)) AND NOT(Mode_reg(1)) AND Mode_reg(0); + Burst_length_4 <= NOT(Mode_reg(2)) AND Mode_reg(1) AND NOT(Mode_reg(0)); + Burst_length_8 <= NOT(Mode_reg(2)) AND Mode_reg(1) AND Mode_reg(0); + Burst_length_f <= (Mode_reg(2)) AND Mode_reg(1) AND Mode_reg(0); + + -- CAS Latency Decode + Cas_latency_15 <= Mode_reg(6) AND NOT(Mode_reg(5)) AND (Mode_reg(4)); + Cas_latency_2 <= NOT(Mode_reg(6)) AND Mode_reg(5) AND NOT(Mode_reg(4)); + Cas_latency_25 <= Mode_reg(6) AND Mode_reg(5) AND NOT(Mode_reg(4)); + Cas_latency_3 <= NOT(Mode_reg(6)) AND Mode_reg(5) AND Mode_reg(4); + Cas_latency_4 <= (Mode_reg(6)) AND NOT(Mode_reg(5)) AND NOT(Mode_reg(4)); + + -- Dqs buffer + Dqs <= Dqs_out; + + -- + -- System Clock + -- + int_clk : PROCESS (Clk, Clk_n) + VARIABLE ClkZ, CkeZ : STD_LOGIC := '0'; + begin + IF Clk = '1' AND Clk_n = '0' THEN + ClkZ := '1'; + CkeZ := Cke; + ELSIF Clk = '0' AND Clk_n = '1' THEN + ClkZ := '0'; + END IF; + Sys_clk <= CkeZ AND ClkZ; + END PROCESS; + + -- + -- Main Process + -- + state_register : PROCESS + -- Precharge Variables + VARIABLE Pc_b0, Pc_b1, Pc_b2, Pc_b3 : STD_LOGIC := '0'; + + -- Activate Variables + VARIABLE Act_b0, Act_b1, Act_b2, Act_b3 : STD_LOGIC := '1'; + + -- Data IO variables + VARIABLE Data_in_enable, Data_out_enable : STD_LOGIC := '0'; + + -- Internal address mux variables + VARIABLE Cols_brst : STD_LOGIC_VECTOR (2 DOWNTO 0); + VARIABLE Prev_bank : STD_LOGIC_VECTOR (1 DOWNTO 0) := "00"; + VARIABLE Bank_addr : STD_LOGIC_VECTOR (1 DOWNTO 0) := "00"; + VARIABLE Cols_addr : STD_LOGIC_VECTOR (cols_bits - 1 DOWNTO 0); + VARIABLE Rows_addr : STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0); + VARIABLE B0_row_addr : STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0); + VARIABLE B1_row_addr : STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0); + VARIABLE B2_row_addr : STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0); + VARIABLE B3_row_addr : STD_LOGIC_VECTOR (addr_bits - 1 DOWNTO 0); + + -- DLL Reset variables + VARIABLE DLL_enable : STD_LOGIC := '0'; + VARIABLE DLL_reset : STD_LOGIC := '0'; + VARIABLE DLL_done : STD_LOGIC := '0'; + VARIABLE DLL_count : INTEGER := 0; + + -- Timing Check + VARIABLE MRD_chk : TIME := 0 ns; + VARIABLE RFC_chk : TIME := 0 ns; + VARIABLE RRD_chk : TIME := 0 ns; + VARIABLE RAS_chk0, RAS_chk1, RAS_chk2, RAS_chk3 : TIME := 0 ns; + VARIABLE RAP_chk0, RAP_chk1, RAP_chk2, RAP_chk3 : TIME := 0 ns; + VARIABLE RC_chk0, RC_chk1, RC_chk2, RC_chk3 : TIME := 0 ns; + VARIABLE RCD_chk0, RCD_chk1, RCD_chk2, RCD_chk3 : TIME := 0 ns; + VARIABLE RP_chk0, RP_chk1, RP_chk2, RP_chk3 : TIME := 0 ns; + VARIABLE WR_chk0, WR_chk1, WR_chk2, WR_chk3 : TIME := 0 ns; + + -- Read pipeline variables + VARIABLE Read_cmnd : Array_Read_cmnd; + VARIABLE Read_bank : Array_Read_bank; + VARIABLE Read_cols : Array_Read_cols; + + -- Write pipeline variables + VARIABLE Write_cmnd : Array_Write_cmnd; + VARIABLE Write_bank : Array_Write_bank; + VARIABLE Write_cols : Array_Write_cols; + + -- Auto Precharge variables + VARIABLE Read_precharge : Array_Read_precharge := ('0' & '0' & '0' & '0'); + VARIABLE Write_precharge : Array_Write_precharge := ('0' & '0' & '0' & '0'); + VARIABLE Count_precharge : Array_Count_precharge := ( 0 & 0 & 0 & 0 ); + + -- Manual Precharge variables + VARIABLE A10_precharge : Array_A10_precharge; + VARIABLE Bank_precharge : Array_Bank_precharge; + VARIABLE Cmnd_precharge : Array_Cmnd_precharge; + + -- Burst Terminate variable + VARIABLE Cmnd_bst : Array_Cmnd_bst; + + -- Memory Banks + VARIABLE Bank0 : Array_ram_stor; + VARIABLE Bank1 : Array_ram_stor; + VARIABLE Bank2 : Array_ram_stor; + VARIABLE Bank3 : Array_ram_stor; + + -- Burst Counter + VARIABLE Burst_counter : STD_LOGIC_VECTOR (cols_bits - 1 DOWNTO 0); + + -- Internal Dqs initialize + VARIABLE Dqs_int : STD_LOGIC := '0'; + + -- Data buffer for DM Mask + VARIABLE Data_buf : STD_LOGIC_VECTOR (data_bits - 1 DOWNTO 0) := (OTHERS => 'Z'); + + -- + -- Initialize empty rows + -- + PROCEDURE Init_mem (Bank : STD_LOGIC_VECTOR; Row_index : INTEGER) IS + VARIABLE i, j : INTEGER := 0; + BEGIN + IF Bank = "00" THEN + IF Bank0 (Row_index) = NULL THEN -- Check to see if row empty + Bank0 (Row_index) := NEW Array_ram_type; -- Open new row for access + FOR i IN (2**cols_bits - 1) DOWNTO 0 LOOP -- Filled row with zeros + FOR j IN (data_bits - 1) DOWNTO 0 LOOP + Bank0 (Row_index) (i) (j) := '0'; + END LOOP; + END LOOP; + END IF; + ELSIF Bank = "01" THEN + IF Bank1 (Row_index) = NULL THEN + Bank1 (Row_index) := NEW Array_ram_type; + FOR i IN (2**cols_bits - 1) DOWNTO 0 LOOP + FOR j IN (data_bits - 1) DOWNTO 0 LOOP + Bank1 (Row_index) (i) (j) := '0'; + END LOOP; + END LOOP; + END IF; + ELSIF Bank = "10" THEN + IF Bank2 (Row_index) = NULL THEN + Bank2 (Row_index) := NEW Array_ram_type; + FOR i IN (2**cols_bits - 1) DOWNTO 0 LOOP + FOR j IN (data_bits - 1) DOWNTO 0 LOOP + Bank2 (Row_index) (i) (j) := '0'; + END LOOP; + END LOOP; + END IF; + ELSIF Bank = "11" THEN + IF Bank3 (Row_index) = NULL THEN + Bank3 (Row_index) := NEW Array_ram_type; + FOR i IN (2**cols_bits - 1) DOWNTO 0 LOOP + FOR j IN (data_bits - 1) DOWNTO 0 LOOP + Bank3 (Row_index) (i) (j) := '0'; + END LOOP; + END LOOP; + END IF; + END IF; + END; + + -- + -- Burst Counter + -- + PROCEDURE Burst_decode IS + VARIABLE Cols_temp : STD_LOGIC_VECTOR (cols_bits - 1 DOWNTO 0) := (OTHERS => '0'); + BEGIN + -- Advance burst counter + Burst_counter := Burst_counter + 1; + + -- Burst Type + IF Mode_reg (3) = '0' THEN + Cols_temp := Cols_addr + 1; + ELSIF Mode_reg (3) = '1' THEN + Cols_temp (2) := Burst_counter (2) XOR Cols_brst (2); + Cols_temp (1) := Burst_counter (1) XOR Cols_brst (1); + Cols_temp (0) := Burst_counter (0) XOR Cols_brst (0); + END IF; + + -- Burst Length + IF Burst_length_2 = '1' THEN + Cols_addr (0) := Cols_temp (0); + ELSIF Burst_length_4 = '1' THEN + Cols_addr (1 DOWNTO 0) := Cols_temp (1 DOWNTO 0); + ELSIF Burst_length_8 = '1' THEN + Cols_addr (2 DOWNTO 0) := Cols_temp (2 DOWNTO 0); + ELSE + Cols_addr := Cols_temp; + END IF; + + -- Data counter + IF Burst_length_2 = '1' THEN + IF Burst_counter >= 2 THEN + IF Data_in_enable = '1' THEN + Data_in_enable := '0'; + ELSIF Data_out_enable = '1' THEN + Data_out_enable := '0'; + END IF; + END IF; + ELSIF Burst_length_4 = '1' THEN + IF Burst_counter >= 4 THEN + IF Data_in_enable = '1' THEN + Data_in_enable := '0'; + ELSIF Data_out_enable = '1' THEN + Data_out_enable := '0'; + END IF; + END IF; + ELSIF Burst_length_8 = '1' THEN + IF Burst_counter >= 8 THEN + IF Data_in_enable = '1' THEN + Data_in_enable := '0'; + ELSIF Data_out_enable = '1' THEN + Data_out_enable := '0'; + END IF; + END IF; + END IF; + END; + + BEGIN + WAIT ON Sys_clk; + + -- + -- Manual Precharge Pipeline + -- + IF ((Sys_clk'EVENT AND Sys_clk = '0') OR (Sys_clk'EVENT AND Sys_clk = '1')) THEN + -- A10 Precharge Pipeline + A10_precharge(0) := A10_precharge(1); + A10_precharge(1) := A10_precharge(2); + A10_precharge(2) := A10_precharge(3); + A10_precharge(3) := A10_precharge(4); + A10_precharge(4) := A10_precharge(5); + A10_precharge(5) := A10_precharge(6); + A10_precharge(6) := A10_precharge(7); + A10_precharge(7) := A10_precharge(8); + A10_precharge(8) := '0'; + + -- Bank Precharge Pipeline + Bank_precharge(0) := Bank_precharge(1); + Bank_precharge(1) := Bank_precharge(2); + Bank_precharge(2) := Bank_precharge(3); + Bank_precharge(3) := Bank_precharge(4); + Bank_precharge(4) := Bank_precharge(5); + Bank_precharge(5) := Bank_precharge(6); + Bank_precharge(6) := Bank_precharge(7); + Bank_precharge(7) := Bank_precharge(8); + Bank_precharge(8) := "00"; + + -- Command Precharge Pipeline + Cmnd_precharge(0) := Cmnd_precharge(1); + Cmnd_precharge(1) := Cmnd_precharge(2); + Cmnd_precharge(2) := Cmnd_precharge(3); + Cmnd_precharge(3) := Cmnd_precharge(4); + Cmnd_precharge(4) := Cmnd_precharge(5); + Cmnd_precharge(5) := Cmnd_precharge(6); + Cmnd_precharge(6) := Cmnd_precharge(7); + Cmnd_precharge(7) := Cmnd_precharge(8); + Cmnd_precharge(8) := '0'; + + -- Terminate Read if same bank or all banks + IF ((Cmnd_precharge (0) = '1') AND + (Bank_precharge (0) = Bank_addr OR A10_precharge (0) = '1') AND + (Data_out_enable = '1')) THEN + Data_out_enable := '0'; + END IF; + END IF; + + -- + -- Burst Terminate Pipeline + -- + IF ((Sys_clk'EVENT AND Sys_clk = '0') OR (Sys_clk'EVENT AND Sys_clk = '1')) THEN + -- Burst Terminate pipeline + Cmnd_bst (0) := Cmnd_bst (1); + Cmnd_bst (1) := Cmnd_bst (2); + Cmnd_bst (2) := Cmnd_bst (3); + Cmnd_bst (3) := Cmnd_bst (4); + Cmnd_bst (4) := Cmnd_bst (5); + Cmnd_bst (5) := Cmnd_bst (6); + Cmnd_bst (6) := Cmnd_bst (7); + Cmnd_bst (7) := Cmnd_bst (8); + Cmnd_bst (8) := '0'; + + -- Terminate current Read + IF ((Cmnd_bst (0) = '1') AND (Data_out_enable = '1')) THEN + Data_out_enable := '0'; + END IF; + END IF; + + -- + -- Dq and Dqs Drivers + -- + IF ((Sys_clk'EVENT AND Sys_clk = '0') OR (Sys_clk'EVENT AND Sys_clk = '1')) THEN + -- Read Command Pipeline + Read_cmnd (0) := Read_cmnd (1); + Read_cmnd (1) := Read_cmnd (2); + Read_cmnd (2) := Read_cmnd (3); + Read_cmnd (3) := Read_cmnd (4); + Read_cmnd (4) := Read_cmnd (5); + Read_cmnd (5) := Read_cmnd (6); + Read_cmnd (6) := Read_cmnd (7); + Read_cmnd (7) := Read_cmnd (8); + Read_cmnd (8) := '0'; + + -- Read Bank Pipeline + Read_bank (0) := Read_bank (1); + Read_bank (1) := Read_bank (2); + Read_bank (2) := Read_bank (3); + Read_bank (3) := Read_bank (4); + Read_bank (4) := Read_bank (5); + Read_bank (5) := Read_bank (6); + Read_bank (6) := Read_bank (7); + Read_bank (7) := Read_bank (8); + Read_bank (8) := "00"; + + -- Read Column Pipeline + Read_cols (0) := Read_cols (1); + Read_cols (1) := Read_cols (2); + Read_cols (2) := Read_cols (3); + Read_cols (3) := Read_cols (4); + Read_cols (4) := Read_cols (5); + Read_cols (5) := Read_cols (6); + Read_cols (6) := Read_cols (7); + Read_cols (7) := Read_cols (8); + Read_cols (8) := (OTHERS => '0'); + + -- Initialize Read command + IF Read_cmnd (0) = '1' THEN + Data_out_enable := '1'; + Bank_addr := Read_bank (0); + Cols_addr := Read_cols (0); + Cols_brst := Cols_addr (2 DOWNTO 0); + Burst_counter := (OTHERS => '0'); + + -- Row address mux + CASE Bank_addr IS + WHEN "00" => Rows_addr := B0_row_addr; + WHEN "01" => Rows_addr := B1_row_addr; + WHEN "10" => Rows_addr := B2_row_addr; + WHEN OTHERS => Rows_addr := B3_row_addr; + END CASE; + END IF; + + -- Toggle Dqs during Read command + IF Data_out_enable = '1' THEN + Dqs_int := '0'; + IF Dqs_out = "00" THEN + Dqs_out <= "11"; + ELSIF Dqs_out = "11" THEN + Dqs_out <= "00"; + ELSE + Dqs_out <= "00"; + END IF; + ELSIF Data_out_enable = '0' AND Dqs_int = '0' THEN + Dqs_out <= "ZZ"; + END IF; + + -- Initialize Dqs for Read command + IF Read_cmnd (2) = '1' THEN + IF Data_out_enable = '0' THEN + Dqs_int := '1'; + Dqs_out <= "00"; + END IF; + END IF; + + -- Read Latch + IF Data_out_enable = '1' THEN + -- Initialize Memory + Init_mem (Bank_addr, CONV_INTEGER(Rows_addr)); + + -- Output Data + CASE Bank_addr IS + WHEN "00" => Dq <= Bank0 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN "01" => Dq <= Bank1 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN "10" => Dq <= Bank2 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN OTHERS => Dq <= Bank3 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + END CASE; + + -- Increase Burst Counter + Burst_decode; + ELSE + Dq <= (OTHERS => 'Z'); + END IF; + END IF; + + -- + -- Write FIFO and DM Mask Logic + -- + IF Sys_clk'EVENT AND Sys_clk = '1' THEN + -- Write command pipeline + Write_cmnd (0) := Write_cmnd (1); + Write_cmnd (1) := Write_cmnd (2); + Write_cmnd (2) := '0'; + + -- Write command pipeline + Write_bank (0) := Write_bank (1); + Write_bank (1) := Write_bank (2); + Write_bank (2) := "00"; + + -- Write column pipeline + Write_cols (0) := Write_cols (1); + Write_cols (1) := Write_cols (2); + Write_cols (2) := (OTHERS => '0'); + + -- Initialize Write command + IF Write_cmnd (0) = '1' THEN + Data_in_enable := '1'; + Bank_addr := Write_bank (0); + Cols_addr := Write_cols (0); + Cols_brst := Cols_addr (2 DOWNTO 0); + Burst_counter := (OTHERS => '0'); + + -- Row address mux + CASE Bank_addr IS + WHEN "00" => Rows_addr := B0_row_addr; + WHEN "01" => Rows_addr := B1_row_addr; + WHEN "10" => Rows_addr := B2_row_addr; + WHEN OTHERS => Rows_addr := B3_row_addr; + END CASE; + END IF; + + -- Write data + IF Data_in_enable = '1' THEN + -- Initialize memory + Init_mem (Bank_addr, CONV_INTEGER(Rows_addr)); + + -- Write first data + IF Dm_pair (1) = '0' OR Dm_pair (0) = '0' THEN + -- Data Buffer + CASE Bank_addr IS + WHEN "00" => Data_buf := Bank0 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN "01" => Data_buf := Bank1 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN "10" => Data_buf := Bank2 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN OTHERS => Data_buf := Bank3 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + END CASE; + + -- Perform DM Mask + IF Dm_pair (0) = '0' THEN + Data_buf ( 7 DOWNTO 0) := Dq_pair ( 7 DOWNTO 0); + END IF; + IF Dm_pair (1) = '0' THEN + Data_buf (15 DOWNTO 8) := Dq_pair (15 DOWNTO 8); + END IF; + + -- Write Data + CASE Bank_addr IS + WHEN "00" => Bank0 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + WHEN "01" => Bank1 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + WHEN "10" => Bank2 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + WHEN OTHERS => Bank3 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + END CASE; + END IF; + + -- Increase Burst Counter + Burst_decode; + + -- Write second data + IF Dm_pair (3) = '0' OR Dm_pair (2) = '0' THEN + -- Data Buffer + CASE Bank_addr IS + WHEN "00" => Data_buf := Bank0 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN "01" => Data_buf := Bank1 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN "10" => Data_buf := Bank2 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + WHEN OTHERS => Data_buf := Bank3 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)); + END CASE; + + -- Perform DM Mask + IF Dm_pair (2) = '0' THEN + Data_buf ( 7 DOWNTO 0) := Dq_pair (23 DOWNTO 16); + END IF; + IF Dm_pair (3) = '0' THEN + Data_buf (15 DOWNTO 8) := Dq_pair (31 DOWNTO 24); + END IF; + + -- Write Data + CASE Bank_addr IS + WHEN "00" => Bank0 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + WHEN "01" => Bank1 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + WHEN "10" => Bank2 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + WHEN OTHERS => Bank3 (CONV_INTEGER(Rows_addr)) (CONV_INTEGER(Cols_addr)) := Data_buf; + END CASE; + END IF; + + -- Increase Burst Counter + Burst_decode; + + -- tWR start and tWTR check + IF Dm_pair (3 DOWNTO 2) = "00" OR Dm_pair (1 DOWNTO 0) = "00" THEN + CASE Bank_addr IS + WHEN "00" => WR_chk0 := NOW; + WHEN "01" => WR_chk1 := NOW; + WHEN "10" => WR_chk2 := NOW; + WHEN OTHERS => WR_chk3 := NOW; + END CASE; + + -- tWTR check + ASSERT (Read_enable = '0') + REPORT "tWTR violation during Read" + SEVERITY WARNING; + END IF; + END IF; + END IF; + + -- + -- Auto Precharge Calculation + -- + IF Sys_clk'EVENT AND Sys_clk = '1' THEN + -- Precharge counter + IF Read_precharge (0) = '1' OR Write_precharge (0) = '1' THEN + Count_precharge (0) := Count_precharge (0) + 1; + END IF; + IF Read_precharge (1) = '1' OR Write_precharge (1) = '1' THEN + Count_precharge (1) := Count_precharge (1) + 1; + END IF; + IF Read_precharge (2) = '1' OR Write_precharge (2) = '1' THEN + Count_precharge (2) := Count_precharge (2) + 1; + END IF; + IF Read_precharge (3) = '1' OR Write_precharge (3) = '1' THEN + Count_precharge (3) := Count_precharge (3) + 1; + END IF; + + -- Read with AutoPrecharge Calculation + -- The device start internal precharge when: + -- 1. Meet tRAS requirement + -- 2. BL/2 cycles after command + IF ((Read_precharge(0) = '1') AND (NOW - RAS_chk0 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge(0) >= 1) OR + (Burst_length_4 = '1' AND Count_precharge(0) >= 2) OR + (Burst_length_8 = '1' AND Count_precharge(0) >= 4)) THEN + Pc_b0 := '1'; + Act_b0 := '0'; + RP_chk0 := NOW; + Read_precharge(0) := '0'; + END IF; + END IF; + IF ((Read_precharge(1) = '1') AND (NOW - RAS_chk1 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge(1) >= 1) OR + (Burst_length_4 = '1' AND Count_precharge(1) >= 2) OR + (Burst_length_8 = '1' AND Count_precharge(1) >= 4)) THEN + Pc_b1 := '1'; + Act_b1 := '0'; + RP_chk1 := NOW; + Read_precharge(1) := '0'; + END IF; + END IF; + IF ((Read_precharge(2) = '1') AND (NOW - RAS_chk2 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge(2) >= 1) OR + (Burst_length_4 = '1' AND Count_precharge(2) >= 2) OR + (Burst_length_8 = '1' AND Count_precharge(2) >= 4)) THEN + Pc_b2 := '1'; + Act_b2 := '0'; + RP_chk2 := NOW; + Read_precharge(2) := '0'; + END IF; + END IF; + IF ((Read_precharge(3) = '1') AND (NOW - RAS_chk3 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge(3) >= 1) OR + (Burst_length_4 = '1' AND Count_precharge(3) >= 2) OR + (Burst_length_8 = '1' AND Count_precharge(3) >= 4)) THEN + Pc_b3 := '1'; + Act_b3 := '0'; + RP_chk3 := NOW; + Read_precharge(3) := '0'; + END IF; + END IF; + + -- Write with AutoPrecharge Calculation + -- The device start internal precharge when: + -- 1. Meet tRAS requirement + -- 2. Two clock after last burst + -- Since tWR is time base, the model will compensate tRP + IF ((Write_precharge(0) = '1') AND (NOW - RAS_chk0 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge (0) >= 4) OR + (Burst_length_4 = '1' AND Count_precharge (0) >= 5) OR + (Burst_length_8 = '1' AND Count_precharge (0) >= 7)) THEN + Pc_b0 := '1'; + Act_b0 := '0'; + RP_chk0 := NOW - ((2 * tCK) - tWR); + Write_precharge(0) := '0'; + END IF; + END IF; + IF ((Write_precharge(1) = '1') AND (NOW - RAS_chk1 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge (1) >= 4) OR + (Burst_length_4 = '1' AND Count_precharge (1) >= 5) OR + (Burst_length_8 = '1' AND Count_precharge (1) >= 7)) THEN + Pc_b1 := '1'; + Act_b1 := '0'; + RP_chk1 := NOW - ((2 * tCK) - tWR); + Write_precharge(1) := '0'; + END IF; + END IF; + IF ((Write_precharge(2) = '1') AND (NOW - RAS_chk2 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge (2) >= 4) OR + (Burst_length_4 = '1' AND Count_precharge (2) >= 5) OR + (Burst_length_8 = '1' AND Count_precharge (2) >= 7)) THEN + Pc_b2 := '1'; + Act_b2 := '0'; + RP_chk2 := NOW - ((2 * tCK) - tWR); + Write_precharge(2) := '0'; + END IF; + END IF; + IF ((Write_precharge(3) = '1') AND (NOW - RAS_chk3 >= tRAS)) THEN + IF ((Burst_length_2 = '1' AND Count_precharge (3) >= 4) OR + (Burst_length_4 = '1' AND Count_precharge (3) >= 5) OR + (Burst_length_8 = '1' AND Count_precharge (3) >= 7)) THEN + Pc_b3 := '1'; + Act_b3 := '0'; + RP_chk3 := NOW - ((2 * tCK) - tWR); + Write_precharge(3) := '0'; + END IF; + END IF; + END IF; + + -- + -- DLL Counter + -- + IF Sys_clk'EVENT AND Sys_clk = '1' THEN + IF (DLL_Reset = '1' AND DLL_done = '0') THEN + DLL_count := DLL_count + 1; + IF (DLL_count >= 200) THEN + DLL_done := '1'; + END IF; + END IF; + END IF; + + -- + -- Control Logic + -- + IF Sys_clk'EVENT AND Sys_clk = '1' THEN + -- Auto Refresh + IF Aref_enable = '1' THEN + -- Auto Refresh to Auto Refresh + ASSERT (NOW - RFC_chk >= tRFC) + REPORT "tRFC violation during Auto Refresh" + SEVERITY WARNING; + + -- Precharge to Auto Refresh + ASSERT ((NOW - RP_chk0 >= tRP) AND (NOW - RP_chk1 >= tRP) AND + (NOW - RP_chk2 >= tRP) AND (NOW - RP_chk3 >= tRP)) + REPORT "tRP violation during Auto Refresh" + SEVERITY WARNING; + + -- Precharge to Auto Refresh + ASSERT (Pc_b0 = '1' AND Pc_b1 = '1' AND Pc_b2 = '1' AND Pc_b3 = '1') + REPORT "All banks must be Precharge before Auto Refresh" + SEVERITY WARNING; + + -- Record current tRFC time + RFC_chk := NOW; + END IF; + + -- Extended Load Mode Register + IF Ext_mode_enable = '1' THEN + IF (Pc_b0 = '1' AND Pc_b1 = '1' AND Pc_b2 = '1' AND Pc_b3 = '1') THEN + IF (Addr (0) = '0') THEN + DLL_enable := '1'; + ELSE + DLL_enable := '0'; + END IF; + END IF; + + -- Precharge to EMR + ASSERT (Pc_b0 = '1' AND Pc_b1 = '1' AND Pc_b2 = '1' AND Pc_b3 = '1') + REPORT "All bank must be Precharged before Extended Mode Register" + SEVERITY WARNING; + + -- Precharge to EMR + ASSERT ((NOW - RP_chk0 >= tRP) AND (NOW - RP_chk1 >= tRP) AND + (NOW - RP_chk2 >= tRP) AND (NOW - RP_chk3 >= tRP)) + REPORT "tRP violation during Extended Load Register" + SEVERITY WARNING; + + -- LMR/EMR to EMR + ASSERT (NOW - MRD_chk >= tMRD) + REPORT "tMRD violation during Extended Mode Register" + SEVERITY WARNING; + + -- Record current tMRD time + MRD_chk := NOW; + END IF; + + -- Load Mode Register + IF Mode_reg_enable = '1' THEN + -- Register mode + Mode_reg <= Addr; + + -- DLL Reset + IF (DLL_enable = '1' AND Addr (8) = '1') THEN + DLL_reset := '1'; + DLL_done := '0'; + DLL_count := 0; + ELSIF (DLL_enable = '1' AND DLL_reset = '0' AND Addr (8) = '0') THEN + ASSERT (FALSE) + REPORT "DLL is ENABLE: DLL RESET is require" + SEVERITY WARNING; + ELSIF (DLL_enable = '0' AND Addr (8) = '1') THEN + ASSERT (FALSE) + REPORT "DLL is DISABLE: DLL RESET will be ignored" + SEVERITY WARNING; + END IF; + + -- Precharge to LMR + ASSERT (Pc_b0 = '1' AND Pc_b1 = '1' AND Pc_b2 = '1' AND Pc_b3 = '1') + REPORT "All bank must be Precharged before Load Mode Register" + SEVERITY WARNING; + + -- Precharge to EMR + ASSERT ((NOW - RP_chk0 >= tRP) AND (NOW - RP_chk1 >= tRP) AND + (NOW - RP_chk2 >= tRP) AND (NOW - RP_chk3 >= tRP)) + REPORT "tRP violation during Load Mode Register" + SEVERITY WARNING; + + -- LMR/ELMR to LMR + ASSERT (NOW - MRD_chk >= tMRD) + REPORT "tMRD violation during Load Mode Register" + SEVERITY WARNING; + + -- Check for invalid Burst Length + ASSERT ((Addr (2 DOWNTO 0) = "001") OR -- BL = 2 + (Addr (2 DOWNTO 0) = "010") OR -- BL = 4 + (Addr (2 DOWNTO 0) = "011")) -- BL = 8 + REPORT "Invalid Burst Length during Load Mode Register" + SEVERITY WARNING; + + -- Check for invalid CAS Latency + ASSERT ((Addr (6 DOWNTO 4) = "010") OR -- CL = 2.0 + (Addr (6 DOWNTO 4) = "110")) -- CL = 2.5 + REPORT "Invalid CAS Latency during Load Mode Register" + SEVERITY WARNING; + + -- Record current tMRD time + MRD_chk := NOW; + END IF; + + -- Active Block (latch Bank and Row Address) + IF Active_enable = '1' THEN + -- Activate an OPEN bank can corrupt data + ASSERT ((Ba = "00" AND Act_b0 = '0') OR + (Ba = "01" AND Act_b1 = '0') OR + (Ba = "10" AND Act_b2 = '0') OR + (Ba = "11" AND Act_b3 = '0')) + REPORT "Bank is already activated - data can be corrupted" + SEVERITY WARNING; + + -- Activate Bank 0 + IF Ba = "00" AND Pc_b0 = '1' THEN + -- Activate to Activate (same bank) + ASSERT (NOW - RC_chk0 >= tRC) + REPORT "tRC violation during Activate Bank 0" + SEVERITY WARNING; + + -- Precharge to Active + ASSERT (NOW - RP_chk0 >= tRP) + REPORT "tRP violation during Activate Bank 0" + SEVERITY WARNING; + + -- Record Variables for checking violation + Act_b0 := '1'; + Pc_b0 := '0'; + B0_row_addr := Addr; + RC_chk0 := NOW; + RCD_chk0 := NOW; + RAS_chk0 := NOW; + RAP_chk0 := NOW; + END IF; + + -- Activate Bank 1 + IF Ba = "01" AND Pc_b1 = '1' THEN + -- Activate to Activate (same bank) + ASSERT (NOW - RC_chk1 >= tRC) + REPORT "tRC violation during Activate Bank 1" + SEVERITY WARNING; + + -- Precharge to Active + ASSERT (NOW - RP_chk1 >= tRP) + REPORT "tRP violation during Activate Bank 1" + SEVERITY WARNING; + + -- Record Variables for checking violation + Act_b1 := '1'; + Pc_b1 := '0'; + B1_row_addr := Addr; + RC_chk1 := NOW; + RCD_chk1 := NOW; + RAS_chk1 := NOW; + RAP_chk1 := NOW; + END IF; + + -- Activate Bank 2 + IF Ba = "10" AND Pc_b2 = '1' THEN + -- Activate to Activate (same bank) + ASSERT (NOW - RC_chk2 >= tRC) + REPORT "tRC violation during Activate Bank 2" + SEVERITY WARNING; + + -- Precharge to Active + ASSERT (NOW - RP_chk2 >= tRP) + REPORT "tRP violation during Activate Bank 2" + SEVERITY WARNING; + + -- Record Variables for checking violation + Act_b2 := '1'; + Pc_b2 := '0'; + B2_row_addr := Addr; + RC_chk2 := NOW; + RCD_chk2 := NOW; + RAS_chk2 := NOW; + RAP_chk2 := NOW; + END IF; + + -- Activate Bank 3 + IF Ba = "11" AND Pc_b3 = '1' THEN + -- Activate to Activate (same bank) + ASSERT (NOW - RC_chk3 >= tRC) + REPORT "tRC violation during Activate Bank 3" + SEVERITY WARNING; + + -- Precharge to Active + ASSERT (NOW - RP_chk3 >= tRP) + REPORT "tRP violation during Activate Bank 3" + SEVERITY WARNING; + + -- Record Variables for checking violation + Act_b3 := '1'; + Pc_b3 := '0'; + B3_row_addr := Addr; + RC_chk3 := NOW; + RCD_chk3 := NOW; + RAS_chk3 := NOW; + RAP_chk3 := NOW; + END IF; + + -- Activate Bank A to Activate Bank B + IF (Prev_bank /= Ba) THEN + ASSERT (NOW - RRD_chk >= tRRD) + REPORT "tRRD violation during Activate" + SEVERITY WARNING; + END IF; + + -- AutoRefresh to Activate + ASSERT (NOW - RFC_chk >= tRFC) + REPORT "tRFC violation during Activate" + SEVERITY WARNING; + + -- Record Variables for Checking Violation + RRD_chk := NOW; + Prev_bank := Ba; + END IF; + + -- Precharge Block - Consider NOP if bank already precharged or in process of precharging + IF Prech_enable = '1' THEN + -- EMR or LMR to Precharge + ASSERT (NOW - MRD_chk >= tMRD) + REPORT "tMRD violation during Precharge" + SEVERITY WARNING; + + -- Precharge Bank 0 + IF ((Addr (10) = '1' OR (Addr (10) = '0' AND Ba = "00")) AND Act_b0 = '1') THEN + Act_b0 := '0'; + Pc_b0 := '1'; + RP_chk0 := NOW; + + -- Activate to Precharge bank 0 + ASSERT (NOW - RAS_chk0 >= tRAS) + REPORT "tRAS violation during Precharge" + SEVERITY WARNING; + + -- tWR violation check for Write + ASSERT (NOW - WR_chk0 >= tWR) + REPORT "tWR violation during Precharge" + SEVERITY WARNING; + END IF; + + -- Precharge Bank 1 + IF ((Addr (10) = '1' OR (Addr (10) = '0' AND Ba = "01")) AND Act_b1 = '1') THEN + Act_b1 := '0'; + Pc_b1 := '1'; + RP_chk1 := NOW; + + -- Activate to Precharge + ASSERT (NOW - RAS_chk1 >= tRAS) + REPORT "tRAS violation during Precharge" + SEVERITY WARNING; + + -- tWR violation check for Write + ASSERT (NOW - WR_chk1 >= tWR) + REPORT "tWR violation during Precharge" + SEVERITY WARNING; + END IF; + + -- Precharge Bank 2 + IF ((Addr (10) = '1' OR (Addr (10) = '0' AND Ba = "10")) AND Act_b2 = '1') THEN + Act_b2 := '0'; + Pc_b2 := '1'; + RP_chk2 := NOW; + + -- Activate to Precharge + ASSERT (NOW - RAS_chk2 >= tRAS) + REPORT "tRAS violation during Precharge" + SEVERITY WARNING; + + -- tWR violation check for Write + ASSERT (NOW - WR_chk2 >= tWR) + REPORT "tWR violation during Precharge" + SEVERITY WARNING; + END IF; + + -- Precharge Bank 3 + IF ((Addr (10) = '1' OR (Addr (10) = '0' AND Ba = "11")) AND Act_b3 = '1') THEN + Act_b3 := '0'; + Pc_b3 := '1'; + RP_chk3 := NOW; + + -- Activate to Precharge + ASSERT (NOW - RAS_chk3 >= tRAS) + REPORT "tRAS violation during Precharge" + SEVERITY WARNING; + + -- tWR violation check for Write + ASSERT (NOW - WR_chk3 >= tWR) + REPORT "tWR violation during Precharge" + SEVERITY WARNING; + END IF; + + -- Pipeline for READ + IF CAS_latency_15 = '1' THEN + A10_precharge (3) := Addr(10); + Bank_precharge (3) := Ba; + Cmnd_precharge (3) := '1'; + ELSIF CAS_latency_2 = '1' THEN + A10_precharge (4) := Addr(10); + Bank_precharge (4) := Ba; + Cmnd_precharge (4) := '1'; + ELSIF CAS_latency_25 = '1' THEN + A10_precharge (5) := Addr(10); + Bank_precharge (5) := Ba; + Cmnd_precharge (5) := '1'; + ELSIF CAS_latency_3 = '1' THEN + A10_precharge (6) := Addr(10); + Bank_precharge (6) := Ba; + Cmnd_precharge (6) := '1'; + ELSIF CAS_latency_4 = '1' THEN + A10_precharge (8) := Addr(10); + Bank_precharge (8) := Ba; + Cmnd_precharge (8) := '1'; + END IF; + END IF; + + -- Burst Terminate + IF Burst_term = '1' THEN + -- Pipeline for Read + IF CAS_latency_15 = '1' THEN + Cmnd_bst (3) := '1'; + ELSIF CAS_latency_2 = '1' THEN + Cmnd_bst (4) := '1'; + ELSIF CAS_latency_25 = '1' THEN + Cmnd_bst (5) := '1'; + ELSIF CAS_latency_3 = '1' THEN + Cmnd_bst (6) := '1'; + ELSIF CAS_latency_4 = '1' THEN + Cmnd_bst (8) := '1'; + END IF; + + -- Terminate Write + ASSERT (Data_in_enable = '0') + REPORT "It's illegal to Burst Terminate a Write" + SEVERITY WARNING; + + -- Terminate Read with Auto Precharge + ASSERT (Read_precharge (0) = '0' AND Read_precharge (1) = '0' AND + Read_precharge (2) = '0' AND Read_precharge (3) = '0') + REPORT "It's illegal to Burst Terminate a Read with Auto Precharge" + SEVERITY WARNING; + END IF; + + -- Read Command + IF Read_enable = '1' THEN + -- CAS Latency Pipeline + IF Cas_latency_15 = '1' THEN + Read_cmnd (3) := '1'; + Read_bank (3) := Ba; + Read_cols (3) := Addr (8 DOWNTO 0); + ELSIF Cas_latency_2 = '1' THEN + Read_cmnd (4) := '1'; + Read_bank (4) := Ba; + Read_cols (4) := Addr (8 DOWNTO 0); + ELSIF Cas_latency_25 = '1' THEN + Read_cmnd (5) := '1'; + Read_bank (5) := Ba; + Read_cols (5) := Addr (8 DOWNTO 0); + ELSIF Cas_latency_3 = '1' THEN + Read_cmnd (6) := '1'; + Read_bank (6) := Ba; + Read_cols (6) := Addr (8 DOWNTO 0); + ELSIF Cas_latency_4 = '1' THEN + Read_cmnd (8) := '1'; + Read_bank (8) := Ba; + Read_cols (8) := Addr (8 DOWNTO 0); + END IF; + + -- Write to Read: Terminate Write Immediately + IF Data_in_enable = '1' THEN + Data_in_enable := '0'; + END IF; + + -- Interrupting a Read with Auto Precharge (same bank only) + ASSERT (Read_precharge(CONV_INTEGER(Ba)) = '0') + REPORT "It's illegal to interrupt a Read with Auto Precharge" + SEVERITY WARNING; + + -- Activate to Read + ASSERT ((Ba = "00" AND Act_b0 = '1') OR + (Ba = "01" AND Act_b1 = '1') OR + (Ba = "10" AND Act_b2 = '1') OR + (Ba = "11" AND Act_b3 = '1')) + REPORT "Bank is not Activated for Read" + SEVERITY WARNING; + + -- Activate to Read without Auto Precharge + IF Addr (10) = '0' THEN + ASSERT ((Ba = "00" AND NOW - RCD_chk0 >= tRCD) OR + (Ba = "01" AND NOW - RCD_chk1 >= tRCD) OR + (Ba = "10" AND NOW - RCD_chk2 >= tRCD) OR + (Ba = "11" AND NOW - RCD_chk3 >= tRCD)) + REPORT "tRCD violation during Read" + SEVERITY WARNING; + END IF; + + -- Activate to Read with Auto Precharge + IF Addr (10) = '1' THEN + ASSERT ((Ba = "00" AND NOW - RAP_chk0 >= tRAP) OR + (Ba = "01" AND NOW - RAP_chk1 >= tRAP) OR + (Ba = "10" AND NOW - RAP_chk2 >= tRAP) OR + (Ba = "11" AND NOW - RAP_chk3 >= tRAP)) + REPORT "tRAP violation during Read" + SEVERITY WARNING; + END IF; + + -- Auto precharge + IF Addr (10) = '1' THEN + Read_precharge (Conv_INTEGER(Ba)) := '1'; + Count_precharge (Conv_INTEGER(Ba)) := 0; + END IF; + + -- DLL Check + IF (DLL_reset = '1') THEN + ASSERT (DLL_done = '1') + REPORT "DLL RESET not complete" + SEVERITY WARNING; + END IF; + END IF; + + -- Write Command + IF Write_enable = '1' THEN + -- Pipeline for Write + Write_cmnd (2) := '1'; + Write_bank (2) := Ba; + Write_cols (2) := Addr (8 DOWNTO 0); + + -- Interrupting a Write with Auto Precharge (same bank only) + ASSERT (Write_precharge(CONV_INTEGER(Ba)) = '0') + REPORT "It's illegal to interrupt a Write with Auto Precharge" + SEVERITY WARNING; + + -- Activate to Write + ASSERT ((Ba = "00" AND Act_b0 = '1') OR + (Ba = "01" AND Act_b1 = '1') OR + (Ba = "10" AND Act_b2 = '1') OR + (Ba = "11" AND Act_b3 = '1')) + REPORT "Bank is not Activated for Write" + SEVERITY WARNING; + + -- Activate to Write + ASSERT ((Ba = "00" AND NOW - RCD_chk0 >= tRCD) OR + (Ba = "01" AND NOW - RCD_chk1 >= tRCD) OR + (Ba = "10" AND NOW - RCD_chk2 >= tRCD) OR + (Ba = "11" AND NOW - RCD_chk3 >= tRCD)) + REPORT "tRCD violation during Write" + SEVERITY WARNING; + + -- Auto precharge + IF Addr (10) = '1' THEN + Write_precharge (Conv_INTEGER(Ba)) := '1'; + Count_precharge (Conv_INTEGER(Ba)) := 0; + END IF; + END IF; + END IF; + END PROCESS; + + -- + -- Dqs Receiver + -- + dqs_rcvrs : PROCESS + VARIABLE Dm_temp : STD_LOGIC_VECTOR (1 DOWNTO 0); + VARIABLE Dq_temp : STD_LOGIC_VECTOR (data_bits - 1 DOWNTO 0); + BEGIN + WAIT ON Dqs; + -- Latch data at posedge Dqs + IF Dqs'EVENT AND Dqs (1) = '1' AND Dqs (0) = '1' THEN + Dq_temp := Dq; + Dm_temp := Dm; + END IF; + -- Latch data at negedge Dqs + IF Dqs'EVENT AND Dqs (1) = '0' AND Dqs (0) = '0' THEN + Dq_pair <= (Dq & Dq_temp); + Dm_pair <= (Dm & Dm_temp); + END IF; + END PROCESS; + + -- + -- Setup timing checks + -- + Setup_check : PROCESS + BEGIN + WAIT ON Sys_clk; + IF Sys_clk'EVENT AND Sys_clk = '1' THEN + ASSERT(Cke'LAST_EVENT >= tIS) + REPORT "CKE Setup time violation -- tIS" + SEVERITY WARNING; + ASSERT(Cs_n'LAST_EVENT >= tIS) + REPORT "CS# Setup time violation -- tIS" + SEVERITY WARNING; + ASSERT(Cas_n'LAST_EVENT >= tIS) + REPORT "CAS# Setup time violation -- tIS" + SEVERITY WARNING; + ASSERT(Ras_n'LAST_EVENT >= tIS) + REPORT "RAS# Setup time violation -- tIS" + SEVERITY WARNING; + ASSERT(We_n'LAST_EVENT >= tIS) + REPORT "WE# Setup time violation -- tIS" + SEVERITY WARNING; + ASSERT(Addr'LAST_EVENT >= tIS) + REPORT "ADDR Setup time violation -- tIS" + SEVERITY WARNING; + ASSERT(Ba'LAST_EVENT >= tIS) + REPORT "BA Setup time violation -- tIS" + SEVERITY WARNING; + END IF; + END PROCESS; + + -- + -- Hold timing checks + -- + Hold_check : PROCESS + BEGIN + WAIT ON Sys_clk'DELAYED (tIH); + IF Sys_clk'DELAYED (tIH) = '1' THEN + ASSERT(Cke'LAST_EVENT >= tIH) + REPORT "CKE Hold time violation -- tIH" + SEVERITY WARNING; + ASSERT(Cs_n'LAST_EVENT >= tIH) + REPORT "CS# Hold time violation -- tIH" + SEVERITY WARNING; + ASSERT(Cas_n'LAST_EVENT >= tIH) + REPORT "CAS# Hold time violation -- tIH" + SEVERITY WARNING; + ASSERT(Ras_n'LAST_EVENT >= tIH) + REPORT "RAS# Hold time violation -- tIH" + SEVERITY WARNING; + ASSERT(We_n'LAST_EVENT >= tIH) + REPORT "WE# Hold time violation -- tIH" + SEVERITY WARNING; + ASSERT(Addr'LAST_EVENT >= tIH) + REPORT "ADDR Hold time violation -- tIH" + SEVERITY WARNING; + ASSERT(Ba'LAST_EVENT >= tIH) + REPORT "BA Hold time violation -- tIH" + SEVERITY WARNING; + END IF; + END PROCESS; + +END behave; |
