Files
vhdl/lib/misc/gpio_wb.vhd
T
jens 0c50e933f8 - changed frequencies into MHz units (real data type)
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git-svn-id: http://moon:8086/svn/vhdl/trunk@734 cc03376c-175c-47c8-b038-4cd826a8556b
2010-02-09 07:50:27 +00:00

326 lines
7.6 KiB
VHDL

LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL;
USE IEEE.NUMERIC_STD.ALL;
ENTITY gpio_wb IS
Generic
(
f_sysclk : real := 100.0
);
Port
(
CLK_I : in STD_LOGIC;
RST_I : in STD_LOGIC;
CYC_I : in STD_LOGIC;
STB_I : in STD_LOGIC;
SEL_I : in unsigned(3 downto 0);
WE_I : in STD_LOGIC;
ACK_O : out STD_LOGIC;
SRDY_O : out STD_LOGIC;
MRDY_I : in STD_LOGIC;
ADDR_I : in unsigned(31 downto 0);
DAT_I : in unsigned(31 downto 0);
DAT_O : out unsigned(31 downto 0);
INT_TIM_O : out STD_LOGIC;
sys_gpo0 : out unsigned(31 downto 0);
sys_gpo1 : out unsigned(31 downto 0);
sys_gpi0 : in unsigned(31 downto 0);
sys_gpi1 : in unsigned(31 downto 0)
);
END gpio_wb;
ARCHITECTURE behavior OF gpio_wb IS
constant num_timers : natural := 2;
constant ncycles_usec : natural := natural(f_sysclk + 0.5);
signal gpo0_reg : unsigned(31 downto 0);
signal gpo1_reg : unsigned(31 downto 0);
signal gpi0_reg : unsigned(31 downto 0);
signal gpi1_reg : unsigned(31 downto 0);
-- Signals to form an timer generating an interrupt every microsecond
subtype tick_usec_t is natural range 0 to ncycles_usec-1;
signal tick_usec : tick_usec_t;
signal cnt_usec : unsigned(31 downto 0);
signal cnt_sec : unsigned(31 downto 0);
signal cnt_usec_preset : unsigned(31 downto 0);
signal cnt_sec_preset : unsigned(31 downto 0);
signal cnt_usec_en : std_logic;
signal cnt_usec_we : std_logic;
signal cnt_sec_en : std_logic;
signal cnt_sec_we : std_logic;
type timer_array_t is array (0 to num_timers-1) of unsigned(31 downto 0);
signal timer_cnt : timer_array_t;
signal timer_cmp : timer_array_t;
signal timer_en : unsigned(0 to num_timers-1);
signal timer_inten : unsigned(0 to num_timers-1);
signal timer_irq : unsigned(0 to num_timers-1);
signal timer_ovl : unsigned(0 to num_timers-1);
signal timer_irq_ack : unsigned(0 to num_timers-1);
signal timer_cnt_we : unsigned(0 to num_timers-1);
signal timer_cmp_we : unsigned(0 to num_timers-1);
signal reg_data_wr : unsigned(31 downto 0);
begin
SRDY_O <= CYC_I;
tim_irq:
process(timer_irq)
variable irq : std_logic;
begin
irq := '0';
for i in 0 to num_timers-1 loop
irq := irq or timer_irq(i);
end loop;
INT_TIM_O <= irq;
end process;
------------------------------------------------------------------
led_out:
process(CLK_I)
begin
if rising_edge(CLK_I) then
sys_gpo0 <= gpo0_reg;
sys_gpo1 <= gpo1_reg;
end if;
end process;
------------------------------------------------------------------
btn_ps2_in:
process(CLK_I)
begin
if rising_edge(CLK_I) then
gpi0_reg <= sys_gpi0;
gpi1_reg <= sys_gpi1;
end if;
end process;
------------------------------------------------------------------
registers_write:
process(CLK_I)
begin
if rising_edge(CLK_I) then
cnt_usec_we <= '0';
cnt_sec_we <= '0';
timer_cnt_we <= (others => '0');
timer_cmp_we <= (others => '0');
timer_irq_ack <= (others => '0');
if RST_I = '1' then
gpo0_reg <= (others => '0');
gpo1_reg <= (others => '0');
timer_en <= (others => '0');
timer_inten <= (others => '0');
elsif (STB_I and CYC_I and WE_I) = '1' then
reg_data_wr <= DAT_I;
case ADDR_I(6 downto 2) is
when "00000" =>
if SEL_I(0) = '1' then
gpo0_reg(7 downto 0) <= DAT_I(7 downto 0);
end if;
if SEL_I(1) = '1' then
gpo0_reg(15 downto 8) <= DAT_I(15 downto 8);
end if;
if SEL_I(2) = '1' then
gpo0_reg(23 downto 16) <= DAT_I(23 downto 16);
end if;
if SEL_I(3) = '1' then
gpo0_reg(31 downto 24) <= DAT_I(31 downto 24);
end if;
when "00001" =>
if SEL_I(0) = '1' then
gpo1_reg(7 downto 0) <= DAT_I(7 downto 0);
end if;
if SEL_I(1) = '1' then
gpo1_reg(15 downto 8) <= DAT_I(15 downto 8);
end if;
if SEL_I(2) = '1' then
gpo1_reg(23 downto 16) <= DAT_I(23 downto 16);
end if;
if SEL_I(3) = '1' then
gpo1_reg(31 downto 24) <= DAT_I(31 downto 24);
end if;
when "00010" =>
cnt_usec_we <= '1';
when "00011" =>
cnt_sec_we <= '1';
when "00110" => -- timer control
for i in 0 to num_timers-1 loop
timer_en(i) <= DAT_I(2*i+0);
timer_inten(i) <= DAT_I(2*i+1);
end loop;
when "00111" => -- timer status
for i in 0 to num_timers-1 loop
timer_irq_ack(i) <= DAT_I(2*i); -- IRQ acknowledge
end loop;
when "01000" => -- timer count 0
timer_cnt_we(0) <= '1';
when "01001" => -- timer count 1
timer_cnt_we(1) <= '1';
when "01100" => -- timer compare 0
timer_cmp_we(0) <= '1';
when "01101" => -- timer compare 1
timer_cmp_we(1) <= '1';
when others => null;
end case;
end if;
end if;
end process;
registers_read:
process(CLK_I)
begin
if rising_edge(CLK_I) then
ACK_O <= '0';
if (STB_I and CYC_I) = '1' then
ACK_O <= not WE_I;
DAT_O <= (others => '0');
case ADDR_I(6 downto 2) is
when "00000" =>
DAT_O <= gpi0_reg;
when "00001" =>
DAT_O <= gpi1_reg;
when "00010" =>
DAT_O <= cnt_usec;
when "00011" =>
DAT_O <= cnt_sec;
when "00110" => -- timer control
for i in 0 to num_timers-1 loop
DAT_O(2*i+0) <= timer_en(i);
DAT_O(2*i+1) <= timer_inten(i);
end loop;
when "00111" => -- timer status
for i in 0 to num_timers-1 loop
DAT_O(2*i+0) <= timer_irq(i);
DAT_O(2*i+1) <= timer_ovl(i);
end loop;
when "01000" => -- timer count 0
DAT_O <= timer_cnt(0);
when "01001" => -- timer count 1
DAT_O <= timer_cnt(1);
when "01100" => -- timer compare 0
DAT_O <= timer_cmp(0);
when "01101" => -- timer compare 1
DAT_O <= timer_cmp(1);
when others => null;
end case;
end if;
end if;
end process;
cnt_usec_tick:
process(CLK_I)
begin
if rising_edge(CLK_I) then
cnt_usec_en <= '0';
if tick_usec >= tick_usec_t'high then
tick_usec <= 0;
cnt_usec_en <= '1';
else
tick_usec <= tick_usec + 1;
end if;
end if;
end process;
-- H/W Clock
cnt_usec_clock:
process(CLK_I)
begin
if rising_edge(CLK_I) then
cnt_sec_en <= '0';
if cnt_usec_we = '1' then
cnt_usec <= reg_data_wr;
elsif cnt_usec_en = '1' then
if cnt_usec >= to_unsigned(1E6 - 1, 32) then
cnt_usec <= (others => '0');
cnt_sec_en <= '1';
else
cnt_usec <= cnt_usec + 1;
end if;
end if;
end if;
end process;
cnt_sec_clock:
process(CLK_I)
begin
if rising_edge(CLK_I) then
if cnt_sec_we = '1' then
cnt_sec <= reg_data_wr;
elsif cnt_sec_en = '1' then
cnt_sec <= cnt_sec + 1;
end if;
end if;
end process;
-- Interrupt timer
proc_int_timer:
process(CLK_I)
begin
if rising_edge(CLK_I) then
for i in 0 to num_timers-1 loop
if RST_I = '1' then
timer_ovl(i) <= '0';
timer_irq(i) <= '0';
elsif timer_irq_ack(i) = '1' then
timer_ovl(i) <= '0';
timer_irq(i) <= '0';
elsif timer_cnt_we(i) = '1' then
timer_cnt(i) <= reg_data_wr;
elsif timer_en(i) = '1' then
if timer_cnt(i) >= timer_cmp(i) then
timer_cnt(i) <= (others => '0');
if timer_inten(i) = '1' then
if timer_irq(i) = '1' then
timer_ovl(i) <= '1';
end if;
timer_irq(i) <= '1';
end if;
else
timer_cnt(i) <= timer_cnt(i) + 1;
end if;
end if;
end loop;
end if;
end process;
proc_int_timer_reload:
process(CLK_I)
begin
if rising_edge(CLK_I) then
for i in 0 to num_timers-1 loop
if timer_cmp_we(i) = '1' then
timer_cmp(i) <= reg_data_wr;
end if;
end loop;
end if;
end process;
------------------------------------------------------------------
end behavior;