-------------------------------------------------------------------------                                                             --------  OpenCores IDE Controller                                   --------  PIO Access Controller (common for OCIDEC 2 and above)      --------                                                             --------  Author: Richard Herveille                                  --------          richard@asics.ws                                   --------          www.asics.ws                                       --------                                                             -----------------------------------------------------------------------------                                                             -------- Copyright (C) 2001, 2002 Richard Herveille                  --------                          richard@asics.ws                   -------                                                             -------- This source file may be used and distributed without        -------- restriction provided that this copyright statement is not   -------- removed from the file and that any derivative work contains -------- the original copyright notice and the associated disclaimer.--------                                                             --------     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     -------- EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   -------- TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   -------- FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      -------- OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         -------- INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    -------- (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   -------- GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        -------- BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  -------- LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  -------- (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  -------- OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         -------- POSSIBILITY OF SUCH DAMAGE.                                 --------                                                             --------------------------------------------------------------------------- rev.: 1.0 march 9th, 2001-- rev.: 1.0a april 12th, 2001 Removed references to records.vhd------  CVS Log----  $Id: atahost_pio_actrl.vhd,v 1.2 2002/05/19 06:07:09 rherveille Exp $----  $Date: 2002/05/19 06:07:09 $--  $Revision: 1.2 $--  $Author: rherveille $--  $Locker:  $--  $State: Exp $---- Change History:--               $Log: atahost_pio_actrl.vhd,v $--               Revision 1.2  2002/05/19 06:07:09  rherveille--               Fixed a potential bug where the core was forced into an unknown state--               when an asynchronous reset was given without a running clock.--------------------------------- PIO Access controller -------------------------------library ieee;use ieee.std_logic_1164.all;use ieee.std_logic_arith.all;entity atahost_pio_actrl is	generic(		TWIDTH : natural := 8;                     -- counter width		-- PIO mode 0 settings (@100MHz clock)		PIO_mode0_T1 : natural := 6;               -- 70ns		PIO_mode0_T2 : natural := 28;              -- 290ns		PIO_mode0_T4 : natural := 2;               -- 30ns		PIO_mode0_Teoc : natural := 23             -- 240ns ==> T0 - T1 - T2 = 600 - 70 - 290 = 240	);	port(		clk    : in std_logic;                     -- master clock		nReset : in std_logic;                     -- asynchronous active low reset		rst    : in std_logic;                     -- synchronous active high reset		IDEctrl_FATR0,		IDEctrl_FATR1 : in std_logic;		cmdport_T1,		cmdport_T2,		cmdport_T4,		cmdport_Teoc : in unsigned(7 downto 0);		cmdport_IORDYen : in std_logic;            -- PIO command port / non-fast timing		dport0_T1,		dport0_T2,		dport0_T4,		dport0_Teoc : in unsigned(7 downto 0);		dport0_IORDYen : in std_logic;             -- PIO mode data-port / fast timing device 0		dport1_T1,		dport1_T2,		dport1_T4,		dport1_Teoc : in unsigned(7 downto 0);		dport1_IORDYen : in std_logic;             -- PIO mode data-port / fast timing device 1		SelDev : in std_logic;                     -- Selected device			go   : in  std_logic;                      -- Start transfer sequence		done : out std_logic;                      -- Transfer sequence done		dir  : in  std_logic;                      -- Transfer direction '1'=write, '0'=read		a    : in  unsigned(3 downto 0);           -- PIO transfer address		q    : out std_logic_vector(15 downto 0);  -- Data read from ATA devices		DDi : in std_logic_vector(15 downto 0);    -- Data from ATA DD bus		oe  : buffer std_logic;                    -- DDbus output-enable signal		DIOR,		DIOW  : buffer std_logic;		IORDY : in std_logic 	);end entity atahost_pio_actrl;architecture structural of atahost_pio_actrl is	--	-- Component declarations	--	component atahost_pio_tctrl is		generic(		TWIDTH : natural := 8;                   -- counter width		-- PIO mode 0 settings (@100MHz clock)		PIO_mode0_T1 : natural := 6;             -- 70ns		PIO_mode0_T2 : natural := 28;            -- 290ns		PIO_mode0_T4 : natural := 2;             -- 30ns		PIO_mode0_Teoc : natural := 23           -- 240ns ==> T0 - T1 - T2 = 600 - 70 - 290 = 240	);	port(		clk    : in std_logic;                   -- master clock		nReset : in std_logic;                   -- asynchronous active low reset		rst    : in std_logic;                   -- synchronous active high reset		-- timing/control register settings		IORDY_en : in std_logic;                 -- use IORDY (or not)		T1   : in unsigned(TWIDTH -1 downto 0);  -- T1 time (in clk-ticks)		T2   : in unsigned(TWIDTH -1 downto 0);  -- T2 time (in clk-ticks)		T4   : in unsigned(TWIDTH -1 downto 0);  -- T4 time (in clk-ticks)		Teoc : in unsigned(TWIDTH -1 downto 0);  -- end of cycle time		-- control signals		go : in std_logic;                       -- PIO controller selected (strobe signal)		we : in std_logic;                       -- write enable signal. '0'=read from device, '1'=write to device		-- return signals		oe    : buffer std_logic;                -- output enable signal		done  : out std_logic;                   -- finished cycle		dstrb : out std_logic;                   -- data strobe, latch data (during read)		-- ATA signals		DIOR,                                    -- IOread signal, active high		DIOW  : buffer std_logic;                -- IOwrite signal, active high		IORDY : in std_logic                     -- IORDY signal	);	end component atahost_pio_tctrl;	signal dstrb : std_logic;	signal T1, T2, T4, Teoc : unsigned(TWIDTH -1 downto 0);	signal IORDYen : std_logic;begin	--	--------------------------	-- PIO transfer control --	--------------------------	--	-- capture ATA data for PIO access	gen_PIOq: process(clk)	begin		if (clk'event and clk = '1') then			if (dstrb = '1') then				q <= DDi;			end if;		end if;	end process gen_PIOq;	--	-- PIO timing controllers	--	-- select timing settings for the addressed port	sel_port_t: process(clk)		variable Asel : std_logic; -- address selected		variable iT1, iT2, iT4, iTeoc : unsigned(TWIDTH -1 downto 0);		variable iIORDYen : std_logic;	begin		-- initially set timing registers to compatible timing		iT1      := cmdport_T1;		iT2      := cmdport_T2;		iT4      := cmdport_T4;		iTeoc    := cmdport_Teoc;		iIORDYen := cmdport_IORDYen;		-- detect data-port access		Asel := not a(3) and not a(2) and not a(1) and not a(0); -- data port		if (Asel = '1') then                                     -- data port selected, 16bit transfers			if ((SelDev = '1') and (IDEctrl_FATR1 = '1')) then    -- data port1 selected and enabled ?				iT1      := dport1_T1;				iT2      := dport1_T2;				iT4      := dport1_T4;				iTeoc    := dport1_Teoc;				iIORDYen := dport1_IORDYen;			elsif((SelDev = '0') and (IDEctrl_FATR0 = '1')) then       -- data port0 selected and enabled ?				iT1      := dport0_T1;				iT2      := dport0_T2;				iT4      := dport0_T4;				iTeoc    := dport0_Teoc;				iIORDYen := dport0_IORDYen;			end if;		end if;		if (clk'event and clk = '1') then			T1      <= iT1;			T2      <= iT2;			T4      <= iT4;			Teoc    <= iTeoc;			IORDYen <= iIORDYen;		end if;	end process sel_port_t;	--	-- hookup timing controller	--	PIO_timing_controller: atahost_pio_tctrl		generic map (			TWIDTH => TWIDTH,			PIO_mode0_T1 => PIO_mode0_T1,			PIO_mode0_T2 => PIO_mode0_T2,			PIO_mode0_T4 => PIO_mode0_T4,			PIO_mode0_Teoc => PIO_mode0_Teoc		)		port map (			clk => clk,			nReset => nReset,			rst => rst,			IORDY_en => IORDYen,			T1 => T1,			T2 => T2,			T4 => T4,			Teoc => Teoc, 			go => go,			we => dir,			oe => oe,			done => done,			dstrb => dstrb,			DIOR => dior,			DIOW => diow,			IORDY => IORDY		);end architecture structural;