first import of dhwk.

[raggedstone] / dhwk / source / COMM_DEC.vhd

-- J.STELZNER\r
-- INFORMATIK-3 LABOR\r
-- 23.08.2006\r
-- File: COMM_DEC.VHD\r
\r
library ieee;\r
use ieee.std_logic_1164.all ;\r
\r
entity COMM_DEC is\r
	port\r
	(\r
	PCI_CLOCK		:in		std_logic; \r
	PCI_RSTn		:in		std_logic; \r
	MY_ADDR			:in		std_logic;\r
	IDSEL_REG		:in		std_logic;\r
	FRAME_REGn	:in		std_logic;\r
	IO_SPACE		:in		std_logic;\r
	AD_REG			:in		std_logic_vector(31 downto 0);\r
	CBE_REGn		:in		std_logic_vector( 3 downto 0);\r
	LAR					:out	std_logic;--LOAD_ADDR_REG\r
	IO_READ			:out	std_logic;\r
	IO_WRITE		:out	std_logic;\r
	CONF_READ		:out	std_logic;\r
	CONF_WRITE	:out	std_logic;\r
	SERR_CHECK	:out	std_logic\r
	);\r
end entity COMM_DEC ;\r
\r
architecture COMM_DEC_DESIGN of COMM_DEC is\r
\r
\r
--PCI Bus Commands \r
--C/BE[3..0] Command Type\r
--------------------------------------\r
--	0000		Interrupt Acknowledge\r
--	0001		Special Cycle\r
--	0010		I/O Read\r
--	0011		I/O Write\r
--	0100		Reserved\r
--	0101		Reserved\r
--	0110		Memory Read\r
--	0111		Memory Write\r
--\r
--	1000		Reserved\r
--	1001		Reserved\r
--	1010		Configuration Read\r
--	1011		Configuration Write\r
--	1100		Memory Read Multiple \r
--	1101		Dual Address Cycle\r
--	1110		Memory Read Line\r
--	1111		Memory Write and Invalidate\r
\r
\r
--PCI Byte Enable \r
--C/BE[3..0] gueltige Datenbits \r
-------------------------------\r
--	0000		AD 31..0\r
--	1000		AD 23..0\r
--	1100		AD 15..0\r
--	1110		AD  7..0\r
\r
	constant	cmd_int_ack			:std_logic_vector(3 downto 0) := "0000";\r
	constant	cmd_sp_cyc			:std_logic_vector(3 downto 0) := "0001";\r
	constant	cmd_io_read			:std_logic_vector(3 downto 0) := "0010";\r
	constant	cmd_io_write		:std_logic_vector(3 downto 0) := "0011";\r
	constant	cmd_res_4				:std_logic_vector(3 downto 0) := "0100";\r
	constant	cmd_res_5				:std_logic_vector(3 downto 0) := "0101";\r
	constant	cmd_mem_read		:std_logic_vector(3 downto 0) := "0110";\r
	constant	cmd_mem_write		:std_logic_vector(3 downto 0) := "0111";\r
	constant	cmd_res_8				:std_logic_vector(3 downto 0) := "1000";\r
	constant	cmd_res_9				:std_logic_vector(3 downto 0) := "1001";\r
	constant	cmd_conf_read		:std_logic_vector(3 downto 0) := "1010";\r
	constant	cmd_conf_write	:std_logic_vector(3 downto 0) := "1011";\r
	constant	cmd_mem_read_m	:std_logic_vector(3 downto 0) := "1100";\r
	constant	cmd_du_adr_cyc	:std_logic_vector(3 downto 0) := "1101";\r
	constant	cmd_mem_read_l	:std_logic_vector(3 downto 0) := "1110";\r
	constant	cmd_mem_write_i	:std_logic_vector(3 downto 0) := "1111";\r
\r
	signal		START						:std_logic; \r
	signal		FRAME_REG_REGn	:std_logic; \r
\r
	signal		SIG_IO_READ			:std_logic; \r
	signal		SIG_IO_WRITE		:std_logic; \r
	signal		SIG_CONF_READ		:std_logic; \r
	signal		SIG_CONF_WRITE	:std_logic; \r
\r
begin\r
\r
	process (PCI_CLOCK, PCI_RSTn) \r
	begin\r
		if	PCI_RSTn = '0'	then	FRAME_REG_REGn	<=	'1';	\r
		elsif (PCI_CLOCK'event and PCI_CLOCK = '1') then\r
\r
			FRAME_REG_REGn	<=	FRAME_REGn; \r
\r
		end if;\r
	end process;\r
\r
\r
	START			<= (not FRAME_REGn) and FRAME_REG_REGn;	\r
\r
\r
\r
	SIG_IO_READ		<= '1'	when	START			= '1'\r
												and		IO_SPACE	= '1'\r
												and		CBE_REGn	= cmd_io_read	\r
												and		MY_ADDR		= '1'\r
							else '0'; \r
\r
\r
	SIG_IO_WRITE	<= '1'	when	START			= '1'\r
												and		IO_SPACE	= '1'\r
												and		CBE_REGn	= cmd_io_write\r
												and		MY_ADDR		= '1'\r
							else '0'; \r
\r
\r
	SIG_CONF_READ	<= '1'	when	START								= '1'\r
												and		AD_REG(1 downto 0)	= "00"\r
												and		CBE_REGn 						= cmd_conf_read\r
												and		IDSEL_REG						= '1'\r
												\r
						else '0'; \r
\r
\r
	SIG_CONF_WRITE	<= '1'	when	START								= '1'\r
													and		AD_REG(1 downto 0)	= "00"\r
													and		CBE_REGn 						= cmd_conf_write\r
													and		IDSEL_REG						= '1'\r
								else '0'; \r
\r
	LAR			<=	START;\r
\r
	SERR_CHECK	<= SIG_IO_READ or SIG_IO_WRITE or SIG_CONF_READ or SIG_CONF_WRITE;	 \r
\r
	IO_READ	  	<= 	SIG_IO_READ;\r
	IO_WRITE  	<=	SIG_IO_WRITE;	 \r
	CONF_READ	  <=	SIG_CONF_READ;	\r
	CONF_WRITE	<= 	SIG_CONF_WRITE;\r
\r
end architecture COMM_DEC_DESIGN ;\r