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Add documentation to DDS Reader

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This commit is contained in:
Greek 2021-02-02 18:56:38 +01:00
parent d1d95c4ec7
commit bcaace1b8c
1 changed files with 410 additions and 260 deletions
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442
src/dds_endpoint.vhd → src/dds_reader.vhd
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@ -4,7 +4,7 @@ use ieee.numeric_std.all;
-- TODO: Check if sample_cnt is always maintained (also with MAX_SAMPLES_PER_INSTANCE = LENGTH_UNLIMITED)
entity history_cache is
entity dds_reader is
generic (
TIME_BASED_FILTER_QOS : DURATION_TYPE := DEFAULT_TIME_BASED_FILTER_QOS;
MAX_INSTANCES : natural := DEFAULT_MAX_INSTANCES;
@ -17,9 +17,12 @@ entity history_cache is
ORDERED_ACCESS : boolean := DEFAULT_ORDERED_ACCESS;
);
port (
-- SYSTEM
clk : in std_logic;
reset : in std_logic;
time : in TIME_TYPE;
-- FROM RTPS ENDPOINT
start_rtps : in std_logic;
opcode_rtps : in HISTORY_CACHE_OPCODE_TYPE;
res_rtps : out HISTORY_CACHE_RESPOSNE_TYPE;
@ -28,7 +31,7 @@ entity history_cache is
ready_in_rtps : out std_logic;
last_word_in_rtps : in std_logic;
--
-- TO USER ENTITY
start_dds : in std_logic;
ack_dds : out std_logic;
opcode_dds : in HISTORY_CACHE_OPCODE_TYPE;
@ -41,8 +44,11 @@ entity history_cache is
get_data : in std_logic;
done_dds : out std_logic;
return_code_dds : out std_logic_vector(RETURN_CODE_WIDTH-1 downto 0);
-- Sample Info
ready_out_dds : in std_logic;
valid_out_dds : out std_logic;
data_out_dds : out std_logic_vector(WORD_WIDTH-1 downto 0);
last_word_out_dds : out std_logic;
-- SAMPLE INFO
si_sample_state : out std_logic_vector(SAMPLE_STATE_KIND_WIDTH-1 downto 0);
si_view_state : out std_logic_vector(VIEW_STATE_KIND_WIDTH-1 downto 0);
si_instance_state : out std_logic_vector(INSTANCE_STATE_KIND_WIDTH-1 downto 0);
@ -56,19 +62,15 @@ entity history_cache is
si_absolute_generation_count : out std_logic_vector(ABSOLUTE_GENERATION_COUNT_WIDTH-1 downto 0);
si_valid_data : out std_logic;
si_valid : out std_logic;
ready_out_dds : in std_logic;
valid_out_dds : out std_logic;
data_out_dds : out std_logic_vector(WORD_WIDTH-1 downto 0);
last_word_out_dds : out std_logic;
-- COMMUNICATION STATUS
status : out std_logic_vector(STATUS_KIND_WIDTH-1 downto 0);
);
end entity;
architecture arch of history_cache is
architecture arch of dds_reader is
--*****CONSTANT DECLARATION*****
-- *SAMPLE MEMORY*
-- Sample Info Memory Size in 4-Byte Words
constant SAMPLE_MEMORY_SIZE : natural := TODO;
-- Sample Info Memory Address Width
@ -78,6 +80,7 @@ architecture arch of history_cache is
-- Highest Sample Info Frame Address
constant MAX_SAMPLE_ADDRESS : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := SAMPLE_MEMORY_MAX_ADDRESS - SAMPLE_INFO_FRAME_SIZE + 1;
-- *PAYLOAD MEMORY*
-- Payload Memory Size in 4-Byte Words
constant PAYLOAD_MEMORY_SIZE : natural := TODO;
-- Payload Memory Address Width
@ -87,6 +90,7 @@ architecture arch of history_cache is
-- Highest Payload Frame Address
constant MAX_PAYLOAD_ADDRESS : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := PAYLOAD_MEMORY_MAX_ADDRESS - PAYLOAD_FRAME_SIZE + 1;
-- *INSTANCE MEMORY*
-- Instance Memory Size in 4-Byte Words
constant INSTANCE_MEMORY_SIZE : natural := TODO;
-- Instance Memory Address Width
@ -98,17 +102,8 @@ architecture arch of history_cache is
-- Address pointing to the beginning of the first Instance Data Frame
constant FIRST_INSTANCE_ADDRESS : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- *INSTANCE MEMORY FRAME FIELD FLAGS*
constant IMF_FLAG_WIDTH : natural := 7;
constant IMF_KEY_HASH_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (0 => 1, others => '0');
constant IMF_STATUS_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (1 => 1, others => '0');
constant IMF_SAMPLE_CNT_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (2 => 1, others => '0');
constant IMF_DISPOSED_CNT_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (3 => 1, others => '0');
constant IMF_NO_WRITERS_CNT_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (4 => 1, others => '0');
constant IMF_IGNORE_DEADLINE_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (5 => 1, others => '0');
constant IMF_WRITER_BITMAP_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (6 => 1, others => '0');
-- *SAMPLE MEMORY FRAME FORMAT*
-- 4-Byte Word Offsets to Beginning of Respective Fields in the Endpoint Memory Frame
constant SMF_STATUS_INFO_OFFSET : natural := 0;
constant SMF_TIMESTAMP_OFFSET : natural := 1;
constant SMF_LIFESPAN_DEADLINE_OFFSET : natural := 3;
@ -118,10 +113,14 @@ architecture arch of history_cache is
constant SMF_NO_WRITERS_GEN_CNT_OFFSET : natural := 8;
constant SMF_PREV_ADDR_OFFSET : natural := 9;
constant SMF_NEXT_ADDR_OFFSET : natural := 10;
-- *PAYLOAD MEMORY FRAME FORMAT*
-- 4-Byte Word Offsets to Beginning of Respective Fields in the Endpoint Memory Frame
constant PMF_NEXT_ADDR_OFFSET : natural := 0;
constant PMF_PAYLOAD_OFFSET : natural := 1;
-- *INSTANCE MEMORY FRAME OFFSET*
-- 4-Byte Word Offsets to Beginning of Respective Fields in the Endpoint Memory Frame
constant IMF_NEXT_ADDR_OFFSET : natural := 0;
constant IMF_KEY_HASH_OFFSET : natural := 1;
constant IMF_STATUS_INFO_OFFSET : natural := 5;
@ -131,11 +130,40 @@ architecture arch of history_cache is
constant IMF_IGNORE_DEADLINE_OFFSET : natural := 9;
constant IMF_WRITER_BITMAP_OFFSET : natural := IMF_IGNORE_DEADLINE_OFFSET+2 when (TIME_BASED_FILTER_QOS /= DURATION_ZERO) else IMF_NO_WRITERS_GEN_CNT_OFFSET+1;
-- *INSTANCE MEMORY FRAME FORMAT FLAGS*
-- Flags mapping to the respective Endpoint Memory Frame Fields
constant IMF_FLAG_WIDTH : natural := 7;
constant IMF_KEY_HASH_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (0 => 1, others => '0');
constant IMF_STATUS_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (1 => 1, others => '0');
constant IMF_SAMPLE_CNT_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (2 => 1, others => '0');
constant IMF_DISPOSED_CNT_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (3 => 1, others => '0');
constant IMF_NO_WRITERS_CNT_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (4 => 1, others => '0');
constant IMF_IGNORE_DEADLINE_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (5 => 1, others => '0');
constant IMF_WRITER_BITMAP_FLAG : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (6 => 1, others => '0');
--*****TYPE DECLARATION*****
-- FSM states. Explained below in detail
type STAGE_TYPE is (IDLE, TODO);
type INST_STAGE_TYPE is (IDLE, TODO);
type INSTANCE_OPCODE_TYPE is (NOP, TODO);
type STAGE_TYPE is (IDLE, UNKNOWN_OPERATION, ADD_SAMPLE_INFO, ADD_PAYLOAD_ADDRESS, ADD_PAYLOAD, NEXT_PAYLOAD_SLOT, ZERO_PAYLOAD, GET_KEY_HASH, INITIATE_INSTANCE_SEARCH,
FILTER_STAGE, UPDATE_INSTANCE, FINALIZE_PAYLOAD, PRE_SAMPLE_FINALIZE, FIND_POS, FIX_POINTERS, FINALIZE_SAMPLE, GET_OLDEST_SAMPLE_INSTANCE, FIND_OLDEST_INST_SAMPLE,
REMOVE_SAMPLE, POST_SAMPLE_REMOVE, SKIP_ADD_REJECT, SKIP_ADD_DROP, REMOVE_WRITER, REMOVE_STALE_INSTANCE, GET_NEXT_SAMPLE, PRE_CALCULATE, FINALIZE_SAMPLE_INFO,
GET_PAYLOAD, FIND_NEXT_INSTANCE, CHECK_INSTANCE, CHECK_LIFESPAN, GET_SAMPLE_REJECTED_STATUS, GET_REQUESTED_DEADLINE_MISSED_STATUS, CHECK_DEADLINE);
-- Instance Memory FSM states. Explained below in detail
type INST_STAGE_TYPE is (IDLE, SEARCH_INSTANCE_HASH, SEARCH_INSTANCE_ADDR, GET_NEXT_INSTANCE, GET_INSTANCE_DATA, FIND_POS, INSERT_INSTANCE, UPDATE_INSTANCE,
REMOVE_INSTANCE, UNMARK_INTANCES);
-- *Instance Memory Opcodes*
-- OPCODE DESCRIPTION
-- SEARCH_INSTANCE_HASH Search Instance based on Key Hash pointed by key_hash.
-- SEARCH_INSTANCE_ADDR Search Instance based on Instance Pointer pointed by inst_addr_update. [This is needed to mark the previous Instance for Instance Removal]
-- INSERT_INSTANCE Insert Instance to memory. The Instance is inserted in Key Hash Numerical Order.
-- UPDATE_INSTANCE Update Instance Data pointed by inst_addr_base. (inst_mem_fields specifies which Fields to update)
-- GET_FIRST_INSTANCE Get Instance Data of first Instance (Instance with smallest Key Hash Numerical Order). (inst_mem_fields specifies which Fields to get)
-- GET_NEXT_INSTANCE Get Instance Data of next Instance (from the Instance pointed by inst_addr_base) (inst_mem_fields specifies which Fields to get)
-- REMOVE_INSTANCE Remove Instance pointed by inst_addr_base
-- GET_INSTANCE Get Data of Instance pointed by inst_addr_update. (inst_mem_fields specifies which Fields to get)
-- UNMARK_INSTANCES Reset the MARK_FLAG of all stored Instances
type INSTANCE_OPCODE_TYPE is (SEARCH_INSTANCE_HASH, SEARCH_INSTANCE_ADDR, INSERT_INSTANCE, UPDATE_INSTANCE, GET_FIRST_INSTANCE, GET_NEXT_INSTANCE, REMOVE_INSTANCE,
GET_INSTANCE, UNMARK_INSTANCES);
-- Record of Instance Data
type INSTANCE_DATA_TYPE is record
key_hash : KEY_HASH_TYPE;
status_info : std_logic_vector(WORD_WIDTH-1 downto 0);
@ -145,6 +173,7 @@ architecture arch of history_cache is
ignore_deadline : TIME_TYPE;
writer_bitmap : ENDPOINT_BITMAP_ARRAY_TYPE;
end record;
-- Zero initialized Endpoint Data
constant ZERO_INSTANCE_DATA : INSTANCE_DATA_TYPE := (
key_hash => (others => (others => '0')),
status_info => (others => '0'),
@ -154,6 +183,7 @@ architecture arch of history_cache is
ignore_deadline => TIME_INVALID,
writer_bitmap => (others => (others => '0'))
);
-- Instance Data Latch used as temporal cache by Instance Memory FSM
type INST_LATCH_DATA_TYPE is record
key_hash : KEY_HASH_TYPE;
status_info : std_logic_vector(CDR_LONG_WIDTH-1 downto 0);
@ -164,6 +194,7 @@ architecture arch of history_cache is
field_flags : std_logic_vector(0 to IMF_FLAG_WIDTH-1);
addr : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0);
end record;
-- Zero initialized Instance Data Latch
constant ZERO_INST_LATCH_DATA : INST_LATCH_DATA_TYPE := (
key_hash => (others => (others => '0')),
status_info => (others => '0'),
@ -176,6 +207,7 @@ architecture arch of history_cache is
);
--*****SIGNAL DECLARATION
-- *SAMPLE MEMORY CONNECTION SIGNALS*
signal sample_addr : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal sample_read : std_logic := '0';
signal sample_read_data, sample_write_data : std_logic_vector(WORD_WIDTH-1 downto 0) := (others => '0');
@ -183,6 +215,7 @@ architecture arch of history_cache is
signal sample_ready_out, sample_valid_out : std_logic := '0';
signal sample_abort_read : std_logic := '0';
-- *PAYLOAD MEMORY CONNECTION SIGNALS*
signal payload_addr : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal payload_read : std_logic := '0';
signal payload_read_data, payload_write_data : std_logic_vector(WORD_WIDTH-1 downto 0) := (others => '0');
@ -190,6 +223,7 @@ architecture arch of history_cache is
signal payload_ready_out, payload_valid_out : std_logic := '0';
signal payload_abort_read : std_logic := '0';
-- *INSTANCE MEMORY CONNECTION SIGNALS*
signal inst_addr : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal inst_read : std_logic := '0';
signal inst_read_data, inst_write_data : std_logic_vector(WORD_WIDTH-1 downto 0) := (others => '0');
@ -197,60 +231,132 @@ architecture arch of history_cache is
signal inst_ready_out, inst_valid_out : std_logic := '0';
signal inst_abort_read : std_logic := '0';
-- *KEY HASH GENERATOR CONNECTION SIGNALS*
signal khg_valid_in, khg_ready_in, khg_last_word_in, khg_valid_out, khg_ready_out, khg_last_word_out : std_logic := '0';
signal khg_data_in, khg_data_out : std_logic_vector(WORD_WIDTH-1 downto 0) := (others => '0');
signal khg_abort : std_logic := '0';
-- *MAIN PROCESS*
-- FSM state
signal stage, stage_next : STAGE_TYPE := IDLE;
-- General Purpose Counter
signal cnt, cnt_next : natural range TODO := 0;
signal empty_sample_list_head, empty_sample_list_head_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal empty_sample_list_tail, empty_sample_list_tail_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal empty_payload_list_head, empty_payload_list_head_next : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal oldest_sample, oldest_sample_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal newest_sample, newest_sample_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal first_unread_sample, first_unread_sample_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal payload_addr_latch_1, payload_addr_latch_1_next : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal payload_addr_latch_2, payload_addr_latch_2_next : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal sample_addr_latch_1, sample_addr_latch_1_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal sample_addr_latch_2, sample_addr_latch_2_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal sample_addr_latch_3, sample_addr_latch_3_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal sample_addr_latch_4, sample_addr_latch_4_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal ts_latch, ts_latch_next : TIME_TYPE := TIME_INVALID;
signal last_read_ts, last_read_ts_next : TIME_TYPE := TIME_INVALID;
signal long_latch, long_latch_next : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
signal payload_mem_full, payload_mem_full_next : std_logic := '0';
signal sample_mem_full, sample_mem_full_next : std_logic := '0';
signal writer_pos, writer_pos_next : natural range TODO := 0;
signal writer_bitmap : ENDPOINT_BITMAP_ARRAY_TYPE;
signal status_info_update : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
signal key_hash, key_hash_next : KEY_HASH_TYPE := (others => (others => '0'));
signal remove_oldest_sample, remove_oldest_sample_next : std_logic := '0';
signal remove_oldest_inst_sample, remove_oldest_inst_sample_next : std_logic := '0';
signal added_new_instance, added_new_instance_next : std_logic := '0';
signal sample_status_info, sample_status_info_next : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
signal gen_cnt : unsigned(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
signal deadline : TIME_TYPE := TIME_INVALID;
signal inst_addr_update : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal sample_cnt : unsigned(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- Counter used to read/write Payload Fames
signal cnt2, cnt2_next : natural range 0 to PAYLOAD_FRAME_SIZE := 0;
-- Counter used to read/write Payload Fames
signal cnt3, cnt3_next : natural range 0 to PAYLOAD_FRAME_SIZE := 0;
signal inst_op_start : std_logic := '0';
signal inst_op_done : std_logic := '0';
signal inst_opcode : INSTANCE_OPCODE_TYPE := NOP;
signal inst_stage, inst_stage_next : INST_STAGE_TYPE := IDLE;
signal inst_addr_base, inst_addr_base_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal inst_next_addr_base, inst_next_addr_base_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal inst_prev_addr_base, inst_prev_addr_base_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal inst_empty_head, inst_empty_head_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal inst_occupied_head, inst_occupied_head_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal inst_latch_data, inst_latch_data_next : INST_LATCH_DATA_TYPE := ZERO_INST_LATCH_DATA;
-- Head of Empty Sample List
signal empty_sample_list_head, empty_sample_list_head_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Tail of Empty Sample List
signal empty_sample_list_tail, empty_sample_list_tail_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Head of Empty Payload List
signal empty_payload_list_head, empty_payload_list_head_next : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Oldest Sample (Head of Occupied Sample List)
signal oldest_sample, oldest_sample_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Newest Sample (Tail of Occupied Sample List)
signal newest_sample, newest_sample_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Highest Timestamp of all READ Samples
signal last_read_ts, last_read_ts_next : TIME_TYPE := TIME_INVALID;
-- Denotes if the oldest Sample should be removed
signal remove_oldest_sample, remove_oldest_sample_next : std_logic := '0';
-- Denotes if the oldest sample of the Instance with 'key_hash' should be removed
signal remove_oldest_inst_sample, remove_oldest_inst_sample_next : std_logic := '0';
-- Denotes if a new Instance was inserted in the Instance Memory
signal added_new_instance, added_new_instance_next : std_logic := '0';
-- Remote Writer Endpoint Bitmap Position
signal writer_pos, writer_pos_next : natural range TODO := 0;
-- Key Hash Latch
signal key_hash, key_hash_next : KEY_HASH_TYPE := (others => (others => '0'));
-- Source Timestamp Latch
signal ts_latch, ts_latch_next : TIME_TYPE := TIME_INVALID;
-- Sample Status Info Latch
signal sample_status_info, sample_status_info_next : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Payload Pointer
signal payload_addr_latch_1, payload_addr_latch_1_next : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Payload Pointer
signal payload_addr_latch_2, payload_addr_latch_2_next : unsigned(PAYLOAD_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Sample Pointer
signal sample_addr_latch_1, sample_addr_latch_1_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Sample Pointer
signal sample_addr_latch_2, sample_addr_latch_2_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Sample Pointer
signal sample_addr_latch_3, sample_addr_latch_3_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Sample Pointer
signal sample_addr_latch_4, sample_addr_latch_4_next : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Long Latch
signal long_latch, long_latch_next : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- Signal used to pass Writer Bitmaps to Instance Memory Process
signal writer_bitmap : ENDPOINT_BITMAP_ARRAY_TYPE;
-- Signal used to pass Sample Status Infos to Instance Memory Process
signal status_info_update : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- Signal used to pass Generation Counters to the Instance Memory Process
signal gen_cnt : unsigned(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- Signal used to pass TIMEs to the Instance Memory Process
signal deadline : TIME_TYPE := TIME_INVALID;
-- Signal containing the relevant Instance Memory Frame Fields of the Instance Memory Operation
signal inst_mem_fields : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (others => '0');
signal inst_cnt, inst_cnt_next : natural range TODO := 0;
signal inst_cnt2, inst_cnt2_next : natural 0 to ENDPOINT_BITMAP_ARRAY_TYPE'length := 0;
signal inst_mem_full, inst_mem_full_next : std_logic := '0';
signal inst_long_latch, inst_long_latch_next : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- Signal used to pass Instance Pointers to the Instance Memory Process
signal inst_addr_update : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Signal used to pass Sample Counts to the Instance Memory Process
signal sample_cnt : unsigned(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
-- Signals start of Instance Memory Operation
signal inst_op_start : std_logic := '0';
-- Opcode of Instance Memory Operation (Valid only when inst_op_start is high)
signal inst_opcode : INSTANCE_OPCODE_TYPE := NOP;
-- Signals the end of an Instance Memory Operation
signal inst_op_done : std_logic := '0';
-- Time of next Sample Lifespan Check
signal lifespan_time, lifespan_time_next : TIME_TYPE := TIME_ZERO;
-- Signifies if a Lifespan Check is in progress
signal is_lifespan_check, is_lifespan_check_next : std_logic := '0';
-- Sample State Latch
signal sample_state, sample_state_next : std_logic_vector(SAMPLE_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
-- View State Latch
signal view_state, view_state_next : std_logic_vector(VIEW_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
-- Instance State Latch
signal instance_state, instance_state_next : std_logic_vector(INSTANCE_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
-- Instance Handle Latch
signal instance_handle, instance_handle_next : INSTANCE_HANDLE_TYPE := (others => '0');
-- Max Samples Latch
signal max_samples, max_samples_next : unsigned(MAX_SAMPLES_WIDTH-1 downto 0) := (others => '0');
-- General Purpose Instance Pointer
signal inst_addr_latch, inst_addr_latch_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Denotes the current length of the Collection
signal collection_cnt, collection_cnt_next : unsigned(MAX_SAMPLES_WIDTH-1 downto 0) := (others => '0');
-- Denotes the current pre-calculated length of the Collection
signal collection_cnt_max, collection_cnt_max_next : unsigned(MAX_SAMPLES_WIDTH-1 downto 0) := (others => '0');
-- Denotes the Generation Rank (For a collection of length collection_cnt_max)
signal collection_generation_rank, collection_generation_rank_next : unsigned(GENERATION_RANK_WIDTH-1 downto 0) := (others => '0');
-- Number of NOT_ALIVE->ALIVE Transitions during reception of selected Sample
signal cur_generation_rank, cur_generation_rank_next : unsigned(GENERATION_RANK_WIDTH-1 downto 0) := (others => '0');
-- Denotes if a TAKE operation is in progress
signal is_take, is_take_next : std_logic := '0';
-- Denotes if the READ/TAKE operation applies to a single Instance
signal single_instance, single_instance_next : std_logic := '0';
-- NOTE: We use this signal to prevent the costly Instance Marking in the case that we only need to ouptput next sample.
-- I.e. make READ_NEXT/TAKE_NEXT the fastest commands.
-- Denotes if the READ/TAKE operation applies only to a single sample
signal single_sample, single_sample_next : std_logic := '0';
-- Denotes if the marks on Instances should be reset
signal unmark_instances, unmark_instances_next : std_logic := '0';
-- Denotes if the READ/TAKE operation does not apply to a specific Instance
signal dynamic_next_instance, dynamic_next_instance_next : std_logic := '0';
-- *COMMUNICATION STATUS*
signal status_sig, status_sig_next : std_logic_vector(STATUS_KIND_WIDTH-1 downto 0) := (others => '0');
-- SAMPLE REJECT STATUS
signal sample_rej_cnt, sample_rej_cnt_next : unsigned(SAMPLE_REJECTED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal sample_rej_cnt_change, sample_rej_cnt_change_next : unsigned(SAMPLE_REJECTED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal sample_rej_last_reason, sample_rej_last_reason_next : std_logic_vector(CDR_ENUMERATION_WIDTH-1 downto 0) := (others =>'0');
signal sample_rej_last_inst, sample_rej_last_inst_next : INSTANCE_HANDLE_TYPE := (others => (others => '0'));
-- REQUESTED DEADLINE MISSED STATUS
-- Time of next Deadline Miss Check
signal deadline_time, deadline_time_next : TIME_TYPE := TIME_ZERO;
signal deadline_miss_cnt, deadline_miss_cnt_next : unsigned(REQUESTED_DEADLINE_MISSED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal deadline_miss_cnt_change, deadline_miss_cnt_change_next : unsigned(REQUESTED_DEADLINE_MISSED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal deadline_miss_last_inst, deadline_miss_last_inst_next : INSTANCE_HANDLE_TYPE := (others => (others => '0'));
-- *SAMPLE INFO*
signal si_sample_state_sig, si_sample_state_sig_next : std_logic_vector(SAMPLE_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
signal si_view_state_sig, si_view_state_sig_next : std_logic_vector(VIEW_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
signal si_instance_state_sig, si_instance_state_sig_next : std_logic_vector(INSTANCE_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
@ -265,38 +371,29 @@ architecture arch of history_cache is
signal si_valid_data_sig, si_valid_data_sig_next : std_logic := '0';
signal si_valid_sig, si_valid_sig_next : std_logic := '0';
signal sample_state, sample_state_next : std_logic_vector(SAMPLE_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
signal view_state, view_state_next : std_logic_vector(VIEW_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
signal instance_state, instance_state_next : std_logic_vector(INSTANCE_STATE_KIND_WIDTH-1 downto 0) := (others => '0');
signal instance_handle, instance_handle_next : INSTANCE_HANDLE_TYPE := (others => '0');
signal max_samples, max_samples_next : unsigned(MAX_SAMPLES_WIDTH-1 downto 0) := (others => '0');
signal inst_addr_latch, inst_addr_latch_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
signal collection_cnt, collection_cnt_next : unsigned(MAX_SAMPLES_WIDTH-1 downto 0) := (others => '0');
signal collection_cnt_max, collection_cnt_max_next : unsigned(MAX_SAMPLES_WIDTH-1 downto 0) := (others => '0');
signal collection_generation_rank, collection_generation_rank_next : unsigned(GENERATION_RANK_WIDTH-1 downto 0) := (others => '0');
signal cur_generation_rank, cur_generation_rank_next : unsigned(GENERATION_RANK_WIDTH-1 downto 0) := (others => '0');
signal is_take, is_take_next : std_logic := '0';
signal has_latched, has_lacthed_next : std_logic := '0';
signal single_instance, single_instance_next : std_logic := '0';
-- NOTE: We use this signal to prevent the costly Instance Marking in the case that we only need to ouptput next sample.
-- I.e. make READ_NEXT/TAKE_NEXT the fastest commands.
signal single_sample, single_sample_next : std_logic := '0';
signal unmark_instances, unmark_instances_next : std_logic := '0';
signal dynamic_next_instance, dynamic_next_instance_next : std_logic := '0';
signal inst_data_variant : INSTANCE_DATA_VARIANT_TYPE := VAR_1;
signal abort_khg : std_logic := '0';
signal lifespan_time, lifespan_time_next : TIME_TYPE := TIME_ZERO;
signal is_lifespan_check, is_lifespan_check_next : std_logic := '0';
signal status_sig, status_sig_next : std_logic_vector(STATUS_KIND_WIDTH-1 downto 0) := (others => '0');
signal sample_rej_cnt, sample_rej_cnt_next : unsigned(SAMPLE_REJECTED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal sample_rej_cnt_change, sample_rej_cnt_change_next : unsigned(SAMPLE_REJECTED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal sample_rej_last_reason, sample_rej_last_reason_next : std_logic_vector(CDR_ENUMERATION_WIDTH-1 downto 0) := (others =>'0');
signal sample_rej_last_inst, sample_rej_last_inst_next : INSTANCE_HANDLE_TYPE := (others => (others => '0'));
signal deadline_time, deadline_time_next : TIME_TYPE := TIME_ZERO;
signal deadline_miss_cnt, deadline_miss_cnt_next : unsigned(REQUESTED_DEADLINE_MISSED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal deadline_miss_cnt_change, deadline_miss_cnt_change_next : unsigned(REQUESTED_DEADLINE_MISSED_STATUS_COUNT_WIDTH-1 downto 0) := (others => '0');
signal deadline_miss_last_inst, deadline_miss_last_inst_next : INSTANCE_HANDLE_TYPE := (others => (others => '0'));
-- *INSTANCE MEMORY PROCESS*
-- Instance Memory FSM state
signal inst_stage, inst_stage_next : INST_STAGE_TYPE := IDLE;
-- Pointer to current relevant Instance Memory Frame Address
signal inst_addr_base, inst_addr_base_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Pointer to next Instance Memory Frame Address
signal inst_next_addr_base, inst_next_addr_base_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Pointer to previous Instacne Memory Address
signal inst_prev_addr_base, inst_prev_addr_base_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Head of Empty Instance List
signal inst_empty_head, inst_empty_head_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Head of Occupied Instance List
signal inst_occupied_head, inst_occupied_head_next : unsigned(INSTANCE_MEMORY_ADDR_WIDTH-1 downto 0) := (others => '0');
-- Latch for Instance Data from main process
signal inst_latch_data, inst_latch_data_next : INST_LATCH_DATA_TYPE := ZERO_INST_LATCH_DATA;
-- Latch for Instance Data from memory
signal inst_data, inst_data_next : INSTANCE_DATA_TYPE := ZERO_INSTANCE_DATA;
-- General Purpose Counter
signal inst_cnt, inst_cnt_next : natural range TODO := 0;
-- Counter used to read/write the Writer Bitmap
signal inst_cnt2, inst_cnt2_next : natural 0 to ENDPOINT_BITMAP_ARRAY_TYPE'length := 0;
-- General Purpose Long Latch
signal inst_long_latch, inst_long_latch_next : std_logic_vector(CDR_LONG_WIDTH-1 downto 0) := (others => '0');
--*****ALIAS DECLARATION*****
alias prev_sample : unsigned(SAMPLE_MEMORY_ADDR_WIDTH-1 downto 0) is sample_addr_latch_1;
@ -332,6 +429,8 @@ architecture arch of history_cache is
begin
--*****COMPONENT INSTANTIATION*****
sample_mem_ctrl_inst : entity work.mem_ctrl(arch)
generic map (
ADDR_WIDTH => SAMPLE_MEMORY_ADDR_WIDTH,
@ -396,7 +495,7 @@ begin
key_hash_generator_inst : entity work.key_hash_generator(arch)
port (
clk => clk,
reset => reset or abort_khg,
reset => reset or khg_abort,
data_in => khg_data_in,
valid_in => khg_valid_in,
ready_in => khg_ready_in,
@ -407,28 +506,50 @@ begin
last_word_out => khg_last_word_out
);
-- *Main State Machine*
-- STATE DESCRIPTION
-- IDLE Idle State. Initiates Deadline Miss Checks, Lifespan Expiry Checks, RTPS Operation handling, and DDS Operation handling, in that priority order.
-- UNKNOWN_OPERATION Dummy State for not supported/unknown DDS Operations
-- ADD_SAMPLE_INFO Latch and store Cache Change (pre-payload)
-- ADD_PAYLOAD_ADDRESS Store payload pointer.
-- ADD_PAYLOAD Push payload to memory and key hash generator (as needed)
-- NEXT_PAYLOAD_SLOT Get pointer to next empty payload slot
-- ZERO_PAYLOAD Fill rest of payload slot with zeroes
-- GET_KEY_HASH Fetch the calculated key hash from the Key Hash Generator
-- INITIATE_INSTANCE_SEARCH Initiate Instance Search Memory Operation. This state is used to start the Search operation as soon as the required data is available
-- FILTER_STAGE This state decides if the RTPS Cache Change is accepted, dropped, or rejected. It also decides what sample (if any) has to be removed.
-- UPDATE_INSTANCE Update the Data of the Instance of the received saample (Cache Change)
-- FINALIZE_PAYLOAD Finalize the payload addition (Update pointers).
-- PRE_SAMPLE_FINALIZE Store Sample Info based on Instance Data
-- FIND_POS Find Sample List position based on DESTINATION_ORDER_QOS
-- FIX_POINTERS Update the List Pointers of the inserted Sample neighbours (First Step of Sample Addition Finalization)
-- FINALIZE_SAMPLE Update inserted sample and list pointers. (Second Step of Sample Addition Finalization)
-- GET_OLDEST_SAMPLE_INSTANCE Fetch the Instance Data of the oldest sample
-- FIND_OLDEST_INST_SAMPLE Find the oldest sample of a specific Instance
-- REMOVE_SAMPLE Remove sample and linked payload
-- POST_SAMPLE_REMOVE Update Instance Data of removed sample. If Instance Memory is full, and Instance is now eligible for removal, it is removed.
-- SKIP_ADD_REJECT Skip RTPS Cache Change and signal rejection to RTPS.
-- SKIP_ADD_DROP Skip RTPS Cache Change and signal acceptance to RTPS.
-- REMOVE_WRITER Unmark specified Writer Bitmap Position from all stored Instances. (Also updates Instance Data if necessary)
-- REMOVE_STALE_INSTANCE Find and remove the first eligible Instance in the memory
-- GET_NEXT_SAMPLE Find the next sample in the requested collection
-- PRE_CALCULATE Calculate ranks for the selected sample in the requested collection.
-- FINALIZE_SAMPLE_INFO Finalize the Sample Info Data, and present them.
-- GET_PAYLOAD Push linked Payload to output
-- FIND_NEXT_INSTANCE Find next Instance that passes requested masks
-- CHECK_INSTANCE Check if selected Instance passes requested masks
-- CHECK_LIFESPAN Check and remove samples with expired Lifespans
-- GET_SAMPLE_REJECTED_STATUS Return Sample Rejected Status
-- GET_REQUESTED_DEADLINE_MISSED_STATUS Return Requested Deadline Missed Status
-- CHECK_DEADLINE Check and Mark Instances with missed Deadlines
parse_a_prc : process (all)
variable tmp_dw : DOUBLE_WORD_ARRAY := (others => (others => '0'));
variable tmp_bitmap : std_logic_vector(0 to ENDPOINT_BITMAP_WIDTH-1) := (others => '0');
variable tmp_update : std_logic_vector(0 to IMF_FLAG_WIDTH-1) := (others => '0');
variable tmp_bool : boolean := FALSE;
begin
-- Default
-- DEFAULT Registered
stage_next <= stage;
res_rtps <= UNDEFINED;
sample_addr <= (others => '0');
sample_write_data <= (others => '0');
sample_read <= '0';
sample_ready_out <= '0';
sample_valid_in <= '0';
sample_abort_read <= '0';
payload_addr <= (others => '0');
payload_write_data <= (others => '0');
payload_read <= '0';
payload_ready_out <= '0';
payload_valid_in <= '0';
payload_abort_read <= '0';
ready_in_rtps <= '0';
newest_sample_next <= newest_sample;
empty_payload_list_head_next <= empty_payload_list_head;
empty_sample_list_head_next <= empty_sample_list_head;
@ -441,19 +562,9 @@ begin
sample_addr_latch_2_next <= sample_addr_latch_2;
sample_addr_latch_3_next <= sample_addr_latch_3;
sample_addr_latch_4_next <= sample_addr_latch_4;
payload_mem_full_next <= payload_mem_full;
sample_mem_full_next <= sample_mem_full;
writer_pos_next <= writer_pos;
inst_opcode <= NOP;
key_hash_next <= key_hash;
sample_status_info_next <= sample_status_info;
inst_op_start <= '0';
khg_last_word_in <= '0';
khg_data_in <= (others => '0');
khg_valid_in <= '0';
khg_ready_out <= '0';
writer_bitmap <= (others => '0');
inst_addr_update <= (others => '0');
remove_oldest_sample_next <= remove_oldest_sample;
remove_oldest_inst_sample_next <= remove_oldest_inst_sample;
added_new_instance_next <= added_new_instance;
@ -482,7 +593,6 @@ begin
collection_generation_rank_next <= collection_generation_rank;
cur_generation_rank_next <= cur_generation_rank;
is_take_next <= is_take;
has_lacthed_next <= has_latched;
single_instance_next <= single_instance;
single_sample_next <= single_sample;
unmark_instances_next <= unmark_instances;
@ -499,13 +609,36 @@ begin
deadline_miss_last_inst_next <= deadline_miss_last_inst;
lifespan_time_next <= lifespan_time;
is_lifespan_check_next <= is_lifespan_check;
ack_dds <= '0';
inst_data_variant <= VAR_1;
done_dds <= '0';
abort_khg <= '0';
return_code_dds <= RETCODE_UNSUPPORTED;
status_sig_next <= status_sig;
cnt2_next <= cnt2;
-- DEFAULT Unregistered
inst_opcode <= NOP;
res_rtps <= UNDEFINED;
return_code_dds <= RETCODE_UNSUPPORTED;
ack_dds <= '0';
done_dds <= '0';
khg_abort <= '0';
inst_op_start <= '0';
khg_last_word_in <= '0';
khg_valid_in <= '0';
khg_ready_out <= '0';
sample_read <= '0';
sample_ready_out <= '0';
sample_valid_in <= '0';
sample_abort_read <= '0';
payload_read <= '0';
payload_ready_out <= '0';
payload_valid_in <= '0';
payload_abort_read <= '0';
ready_in_rtps <= '0';
khg_data_in <= (others => '0');
writer_bitmap <= (others => '0');
inst_addr_update <= (others => '0');
sample_addr <= (others => '0');
sample_write_data <= (others => '0');
payload_addr <= (others => '0');
payload_write_data <= (others => '0');
case (stage) is
when IDLE =>
@ -537,6 +670,7 @@ begin
stage_next <= CHECK_LIFESPAN;
cnt_next <= 0;
end if;
-- RTPS Operation
elsif (start_rtps = '1') then
case (opcode_rtps) is
when ADD_CHANGE =>
@ -562,13 +696,15 @@ begin
when others =>
null;
end case;
-- Unmark Instances
elsif (unmark_instances = '1') then
-- Memory Operation Guard
if (inst_op_done = '1') then
inst_op_start <= '1';
inst_opcode <= UNMARK_INTANCES;
inst_opcode <= UNMARK_INSTANCES;
unmark_instances_next <= '0';
end if;
-- DDS Operation
elsif (start_dds = '1') then
-- Latch Input Signals
sample_state_next <= sample_state_in;
@ -861,6 +997,7 @@ begin
-- End of Payload Slot
if (cnt2 = PAYLOAD_FRAME_SIZE-1) then
stage_next <= NEXT_PAYLOAD_SLOT;
cnt_next <= 0;
else
-- Next Word
cnt_next <= 0;
@ -940,7 +1077,7 @@ begin
-- Reject Change
stage_next <= SKIP_ADD_REJECT;
-- Abort Key Hash Generation
abort_khg <= '1';
khg_abort <= '1';
else
-- Latch next Payload Slot and Continue
cur_payload_next <= payload_read_data;
@ -1922,6 +2059,8 @@ begin
when REMOVE_WRITER =>
-- Memory Operation Guard
if (inst_op_done = '1') then
case (cnt) is
when 0 =>
-- No More Instances
if (inst_addr_base = INSTANCE_MEMORY_MAX_ADDRESS) then
-- DONE
@ -1953,16 +2092,18 @@ begin
inst_mem_fields <= IMF_WRITER_BITMAP_FLAG;
end if;
stage_next <= GET_NEXT_INSTANCE;
-- Continue
cnt_next <= 1;
end if;
end if;
when GET_NEXT_INSTANCE =>
-- Wait for Operation to Complete
if (inst_op_done = '1') then
when 1 =>
inst_op_start <= '1';
inst_opcode <= GET_NEXT_INSTANCE;
inst_mem_fields <= IMF_STATUS_FLAG or IMF_WRITER_BITMAP_FLAG;
stage_next <= REMOVE_WRITER;
cnt_next <= 0;
when others =>
null;
end case;
end if;
when REMOVE_STALE_INSTANCE =>
-- Wait for Instance Data
@ -3247,7 +3388,18 @@ begin
end case;
end process;
-- *Instance Memory Process*
-- STATE DESCRIPTION
-- IDLE Idle State. Done Signal is pulled high and Memory FSM accepts new memory operations
-- SEARCH_INSTANCE_HASH See Memory OPCODE Description
-- SEARCH_INSTANCE_ADDR See Memory OPCODE Description
-- GET_NEXT_INSTANCE See Memory OPCODE Description
-- GET_INSTANCE_DATA Latch specified Instance Data for use by main process
-- FIND_POS Find List position of Instance to be added
-- INSERT_INSTANCE See Memory OPCODE Description
-- UPDATE_INSTANCE See Memory OPCODE Description
-- REMOVE_INSTANCE See Memory OPCODE Description
-- UNMARK_INTANCES See Memory OPCODE Description
inst_ctrl_prc : process(all)
begin
-- DEFAULT Registered
@ -3260,7 +3412,6 @@ begin
inst_prev_addr_base_next <= inst_prev_addr_base;
inst_cnt_next <= inst_cnt;
inst_cnt2_next <= inst_cnt2;
inst_mem_full_next <= inst_mem_full;
inst_data_next <= inst_data;
inst_long_latch_next <= inst_long_latch;
-- DEFAULT Unregistered
@ -3326,7 +3477,6 @@ begin
inst_cnt_next <= 0;
when UPDATE_INSTANCE =>
inst_stage_next <= UPDATE_INSTANCE;
inst_addr_base_next <= inst_addr_update;
if check_mask(inst_mem_fields.field_flag,IMF_STATUS_FLAG) then
inst_cnt_next <= 0;
elsif check_mask(inst_mem_fields.field_flag,IMF_SAMPLE_CNT_FLAG) then
@ -3409,11 +3559,11 @@ begin
-- DONE
inst_stage_next <= IDLE;
end if;
when UNMARK_INTANCES =>
when UNMARK_INSTANCES =>
-- Empty Memory Guard
if (inst_occupied_head /= INSTANCE_MEMORY_MAX_ADDRESS) then
inst_addr_base_next <= inst_occupied_head;
inst_stage_next <= UNMARK_INTANCES;
inst_stage_next <= UNMARK_INSTANCES;
inst_cnt_next <= 0;
end if;
when others =>
@ -4681,7 +4831,7 @@ begin
when others =>
null;
end case;
when UNMARK_INTANCES =>
when UNMARK_INSTANCES =>
-- Precondition: inst_addr_base set
case (inst_cnt) is