cpu/src/extension_imp_b.vhd

   1 library IEEE;
   2 use IEEE.std_logic_1164.all;
   3 use IEEE.numeric_std.all;
   4 use IEEE.STD_LOGIC_ARITH.ALL;
   5 use IEEE.STD_LOGIC_UNSIGNED.ALL;
   6
   7 use work.common_pkg.all;
   8 use work.core_pkg.all;
   9
  10
  11 use work.mem_pkg.all;
  12 use work.extension_pkg.all;
  13 use work.extension_imp_pkg.all;
  14
  15 architecture behav of extension_imp is
  16
  17 signal w1_st_co, w1_st_co_nxt, w2_im_addr, w2_im_addr_nxt, w3_im_data, w3_im_data_nxt, w4_im_notused, w4_im_notused_nxt : gp_register_t;
  18 signal new_im_data, new_im_data_nxt: std_logic;
  19
  20 begin
  21
  22
  23 syn : process (clk, reset)
  24 begin
  25    if (reset = RESET_VALUE) then
  26                         w1_st_co <= (others=>'0');
  27                         w2_im_addr(31 downto 16) <= (others=>'0');
  28                         -- todo mit einer konstante versehen
  29                         w2_im_addr(15 downto 0) <= x"0003";
  30                         w3_im_data <= (others=>'0');
  31                         w4_im_notused <= (others=>'0');
  32                         --im only
  33                         new_im_data <= '0';
  34
  35
  36         elsif rising_edge(clk) then
  37                         w1_st_co <= w1_st_co_nxt;
  38                         w2_im_addr <= w2_im_addr_nxt;
  39                         w3_im_data <= w3_im_data_nxt;
  40                         w4_im_notused <= w4_im_notused_nxt;
  41                         --im only
  42                         new_im_data <= new_im_data_nxt;
  43
  44    end if;
  45 end process syn;
  46
  47 -------------------------- LESEN UND SCHREIBEN ANFANG ------------------------------------------------------------
  48
  49 gwriten : process (ext_reg,w1_st_co,w2_im_addr,w3_im_data,w4_im_notused)
  50
  51 variable tmp_data  : gp_register_t;
  52
  53 begin
  54
  55                 w1_st_co_nxt <= w1_st_co;
  56                 w2_im_addr_nxt <= w2_im_addr;
  57                 w3_im_data_nxt <= w3_im_data;
  58                 w4_im_notused_nxt <= w4_im_notused;
  59
  60         if ext_reg.sel = '1' and ext_reg.wr_en = '1' then
  61                 tmp_data := (others =>'0');
  62                 if ext_reg.byte_en(0) = '1' then
  63                         tmp_data(byte_t'range) :=ext_reg.data(byte_t'range);
  64                 end if;
  65                 if ext_reg.byte_en(1) = '1' then
  66                         tmp_data((2*byte_t'length-1) downto byte_t'length) := ext_reg.data((2*byte_t'length-1) downto byte_t'length);
  67                 end if;
  68                 if ext_reg.byte_en(2) = '1' then
  69                         tmp_data((3*byte_t'length-1) downto 2*byte_t'length) := ext_reg.data((3*byte_t'length-1) downto 2*byte_t'length);
  70                 end if;
  71                 if ext_reg.byte_en(3) = '1' then
  72                         tmp_data((4*byte_t'length-1) downto 3*byte_t'length) := ext_reg.data((4*byte_t'length-1) downto 3*byte_t'length);
  73                 end if;
  74
  75                 case ext_reg.addr(1 downto 0) is
  76                 when "00" =>
  77                         w1_st_co_nxt <= tmp_data;
  78                 when "01" =>
  79                         -- -1 wegen increment des addr registers
  80                         tmp_data := tmp_data - '1';
  81                         w2_im_addr_nxt <= tmp_data;
  82                 when "10" =>
  83                         w1_st_co_nxt(0) <= '1'; -- busy flag set
  84                         w2_im_addr_nxt <= w2_im_addr + '1';
  85                         w3_im_data_nxt <= tmp_data;
  86                 when "11" =>
  87                         --w4_im_notused_nxt <= tmp_data; sollte nur gelesen werden
  88                 when others => null;
  89                 end case;
  90         end if;
  91
  92 end process gwriten;
  93
  94 gread : process (clk,ext_reg,w1_st_co,w2_im_addr,w3_im_data,w4_im_notused)
  95
  96 variable tmp_data  : gp_register_t;
  97
  98 begin
  99         if ext_reg.sel = '1' and ext_reg.wr_en = '0' then
 100                 case ext_reg.addr(1 downto 0) is
 101                 when "00" =>
 102                         tmp_data := (others =>'0');
 103                         if ext_reg.byte_en(0) = '1' then
 104                                 tmp_data(byte_t'range) := w1_st_co(byte_t'range);
 105                         end if;
 106                         if ext_reg.byte_en(1) = '1' then
 107                                 tmp_data((2*byte_t'length-1) downto byte_t'length) := w1_st_co((2*byte_t'length-1) downto byte_t'length);
 108                         end if;
 109                         if ext_reg.byte_en(2) = '1' then
 110                                 tmp_data((3*byte_t'length-1) downto 2*byte_t'length) := w1_st_co((3*byte_t'length-1) downto 2*byte_t'length);
 111                         end if;
 112                         if ext_reg.byte_en(3) = '1' then
 113                                 tmp_data((4*byte_t'length-1) downto 3*byte_t'length) := w1_st_co((4*byte_t'length-1) downto 3*byte_t'length);
 114                         end if;
 115                         data_out <= tmp_data;
 116                 when "01" =>
 117                         tmp_data := (others =>'0');
 118                         if ext_reg.byte_en(0) = '1' then
 119                                 tmp_data(byte_t'range) := w2_im_addr(byte_t'range);
 120                         end if;
 121                         if ext_reg.byte_en(1) = '1' then
 122                                 tmp_data((2*byte_t'length-1) downto byte_t'length) := w2_im_addr((2*byte_t'length-1) downto byte_t'length);
 123                         end if;
 124                         if ext_reg.byte_en(2) = '1' then
 125                                 tmp_data((3*byte_t'length-1) downto 2*byte_t'length) := w2_im_addr((3*byte_t'length-1) downto 2*byte_t'length);
 126                         end if;
 127                         if ext_reg.byte_en(3) = '1' then
 128                                 tmp_data((4*byte_t'length-1) downto 3*byte_t'length) := w2_im_addr((4*byte_t'length-1) downto 3*byte_t'length);
 129                         end if;
 130                         data_out <= tmp_data;
 131                 when "10" =>
 132                         tmp_data := (others =>'0');
 133                         if ext_reg.byte_en(0) = '1' then
 134                                 tmp_data(byte_t'range) := w3_im_data(byte_t'range);
 135                         end if;
 136                         if ext_reg.byte_en(1) = '1' then
 137                                 tmp_data((2*byte_t'length-1) downto byte_t'length) := w3_im_data((2*byte_t'length-1) downto byte_t'length);
 138                         end if;
 139                         if ext_reg.byte_en(2) = '1' then
 140                                 tmp_data((3*byte_t'length-1) downto 2*byte_t'length) := w3_im_data((3*byte_t'length-1) downto 2*byte_t'length);
 141                         end if;
 142                         if ext_reg.byte_en(3) = '1' then
 143                                 tmp_data((4*byte_t'length-1) downto 3*byte_t'length) := w3_im_data((4*byte_t'length-1) downto 3*byte_t'length);
 144                         end if;
 145                         data_out <= tmp_data;
 146                 when "11" =>
 147                         tmp_data := (others =>'0');
 148                         if ext_reg.byte_en(0) = '1' then
 149                                 tmp_data(byte_t'range) := w4_im_notused(byte_t'range);
 150                         end if;
 151                         if ext_reg.byte_en(1) = '1' then
 152                                 tmp_data((2*byte_t'length-1) downto byte_t'length) := w4_im_notused((2*byte_t'length-1) downto byte_t'length);
 153                         end if;
 154                         if ext_reg.byte_en(2) = '1' then
 155                                 tmp_data((3*byte_t'length-1) downto 2*byte_t'length) := w4_im_notused((3*byte_t'length-1) downto 2*byte_t'length);
 156                         end if;
 157                         if ext_reg.byte_en(3) = '1' then
 158                                 tmp_data((4*byte_t'length-1) downto 3*byte_t'length) := w4_im_notused((4*byte_t'length-1) downto 3*byte_t'length);
 159                         end if;
 160                         data_out <= tmp_data;
 161                 when others => null;
 162                 end case;
 163         else
 164                 data_out  <= (others=>'0');
 165         end if;
 166 end process gread;
 167
 168
 169 -------------------------- LESEN UND SCHREIBEN ENDE ---------------------------------------------------------------
 170
 171 -------------------------- INTERNE VERARBEITUNG ANFANG ------------------------------------------------------------
 172
 173 dataprocess : process (ext_reg)
 174
 175
 176 begin
 177 new_im_data_nxt <= '0';
 178 if ext_reg.sel = '1' and ext_reg.wr_en = '1' then
 179                 case ext_reg.addr(1 downto 0) is
 180                 when "00" =>
 181
 182                 when "01" =>
 183
 184                 when "10" =>
 185                         new_im_data_nxt <= '1';
 186                 when "11" =>
 187
 188                 when others => null;
 189                 end case;
 190         end if;
 191
 192 end process dataprocess;
 193 -- asyncrone verarbeitung
 194 im_addr <= w2_im_addr;
 195 im_data <= w3_im_data;
 196 new_im_data_out <= new_im_data;
 197
 198
 199
 200
 201 -------------------------- INTERNE VERARBEITUNG ENDE --------------------------------------------------------------
 202
 203 end behav;
 204