arith.vhd
143 lines
| 4.5 KiB
| text/x-vhdl
|
VhdlLexer
martin
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r100 | ------------------------------------------------------------------------------ | ||
-- This file is a part of the GRLIB VHDL IP LIBRARY | ||||
-- Copyright (C) 2003 - 2008, Gaisler Research | ||||
-- Copyright (C) 2008 - 2010, Aeroflex Gaisler | ||||
-- | ||||
-- This program is free software; you can redistribute it and/or modify | ||||
-- it under the terms of the GNU General Public License as published by | ||||
-- the Free Software Foundation; either version 2 of the License, or | ||||
-- (at your option) any later version. | ||||
-- | ||||
-- This program is distributed in the hope that it will be useful, | ||||
-- but WITHOUT ANY WARRANTY; without even the implied warranty of | ||||
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||||
-- GNU General Public License for more details. | ||||
-- | ||||
-- You should have received a copy of the GNU General Public License | ||||
-- along with this program; if not, write to the Free Software | ||||
-- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||||
----------------------------------------------------------------------------- | ||||
-- Package: arith | ||||
-- File: arith.vhd | ||||
-- Author: Jiri Gaisler, Gaisler Research | ||||
-- Description: Declaration of mul/div components | ||||
------------------------------------------------------------------------------ | ||||
library ieee; | ||||
use ieee.std_logic_1164.all; | ||||
use ieee.numeric_std.all; | ||||
package arith is | ||||
type div32_in_type is record | ||||
y : std_logic_vector(32 downto 0); -- Y (MSB divident) | ||||
op1 : std_logic_vector(32 downto 0); -- operand 1 (LSB divident) | ||||
op2 : std_logic_vector(32 downto 0); -- operand 2 (divisor) | ||||
flush : std_logic; | ||||
signed : std_logic; | ||||
start : std_logic; | ||||
end record; | ||||
type div32_out_type is record | ||||
ready : std_logic; | ||||
nready : std_logic; | ||||
icc : std_logic_vector(3 downto 0); -- ICC | ||||
result : std_logic_vector(31 downto 0); -- div result | ||||
end record; | ||||
type mul32_in_type is record | ||||
op1 : std_logic_vector(32 downto 0); -- operand 1 | ||||
op2 : std_logic_vector(32 downto 0); -- operand 2 | ||||
flush : std_logic; | ||||
signed : std_logic; | ||||
start : std_logic; | ||||
mac : std_logic; | ||||
acc : std_logic_vector(39 downto 0); | ||||
--y : std_logic_vector(7 downto 0); -- Y (MSB MAC register) | ||||
--asr18 : std_logic_vector(31 downto 0); -- LSB MAC register | ||||
end record; | ||||
type mul32_out_type is record | ||||
ready : std_logic; | ||||
nready : std_logic; | ||||
icc : std_logic_vector(3 downto 0); -- ICC | ||||
result : std_logic_vector(63 downto 0); -- mul result | ||||
end record; | ||||
component div32 | ||||
port ( | ||||
rst : in std_ulogic; | ||||
clk : in std_ulogic; | ||||
holdn : in std_ulogic; | ||||
divi : in div32_in_type; | ||||
divo : out div32_out_type | ||||
); | ||||
end component; | ||||
component mul32 | ||||
generic ( | ||||
tech : integer := 0; | ||||
multype : integer := 0; | ||||
pipe : integer := 0; | ||||
mac : integer := 0; | ||||
arch : integer range 0 to 3 := 0 | ||||
); | ||||
port ( | ||||
rst : in std_ulogic; | ||||
clk : in std_ulogic; | ||||
holdn : in std_ulogic; | ||||
muli : in mul32_in_type; | ||||
mulo : out mul32_out_type | ||||
); | ||||
end component; | ||||
function smult ( a, b : in std_logic_vector) return std_logic_vector; | ||||
function umult ( a, b : in std_logic_vector) return std_logic_vector; | ||||
end; | ||||
package body arith is | ||||
function smult ( a, b : in std_logic_vector) return std_logic_vector is | ||||
variable sa : signed (a'length-1 downto 0); | ||||
variable sb : signed (b'length-1 downto 0); | ||||
variable sc : signed ((a'length + b'length) -1 downto 0); | ||||
variable res : std_logic_vector ((a'length + b'length) -1 downto 0); | ||||
begin | ||||
sa := signed(a); sb := signed(b); | ||||
-- pragma translate_off | ||||
if is_x(a) or is_x(b) then | ||||
sc := (others => 'X'); | ||||
else | ||||
-- pragma translate_on | ||||
sc := sa * sb; | ||||
-- pragma translate_off | ||||
end if; | ||||
-- pragma translate_on | ||||
res := std_logic_vector(sc); | ||||
return(res); | ||||
end; | ||||
function umult ( a, b : in std_logic_vector) return std_logic_vector is | ||||
variable sa : unsigned (a'length-1 downto 0); | ||||
variable sb : unsigned (b'length-1 downto 0); | ||||
variable sc : unsigned ((a'length + b'length) -1 downto 0); | ||||
variable res : std_logic_vector ((a'length + b'length) -1 downto 0); | ||||
begin | ||||
sa := unsigned(a); sb := unsigned(b); | ||||
-- pragma translate_off | ||||
if is_x(a) or is_x(b) then | ||||
sc := (others => 'X'); | ||||
else | ||||
-- pragma translate_on | ||||
sc := sa * sb; | ||||
-- pragma translate_off | ||||
end if; | ||||
-- pragma translate_on | ||||
res := std_logic_vector(sc); | ||||
return(res); | ||||
end; | ||||
end; | ||||