Checksum Calculator
- ENTITY CHECKSUM_CALCULATOR IS
This component calculates checksum from the Section of each frame specified by the Offset and Length. The IPv4(=TCP=UDP) checksum algorithm is used. The calculation can be “disabled” per each frame by setting the RX_CHSUM_EN to 0. This dis/enabling of the checksum results in propagating the inverted value of the RX_CHSUM_EN to the TX_CHSUM_BYPASS output (to be reworked).
Generics
PortsGeneric
Type
Default
Description
MFB_REGIONS
natural
4
Number of Regions within a data word, must be power of 2.
MFB_REGION_SIZE
natural
8
Region size (in Blocks).
MFB_BLOCK_SIZE
natural
8
Block size (in Items).
MFB_ITEM_WIDTH
natural
8
Item width (in bits), must be 8.
MFB_META_WIDTH
natural
0
Metadata width (in bits), valid with SOF.
PKT_MTU
natural
2**14
Maximum size of a packet (in Items).
OFFSET_WIDTH
integer
7
Width of each Offset signal in the in the RX_OFFSET vector.
LENGTH_WIDTH
integer
9
Width of each Length signal in the in the RX_LENGTH vector.
NETWORK_ORDER
boolean
False
Select Network order (checksum bytes are swapped at the output).
DEVICE
string
“STRATIX10”
FPGA device name. Options: ULTRASCALE, STRATIX10, AGILEX, …
Port
Type
Mode
Description
=====
Clock and Reset
=====
=====
CLK
std_logic
in
RESET
std_logic
in
=====
RX STREAM
=====
Input packets (MFB),
Meta information (header offsets and lengths).
RX_MFB_DATA
std_logic_vector(MFB_REGIONS*MFB_REGION_SIZE*MFB_BLOCK_SIZE*MFB_ITEM_WIDTH-1 downto 0)
in
RX_MFB_META
std_logic_vector(MFB_REGIONS*MFB_META_WIDTH-1 downto 0)
in
RX_MFB_SOF_POS
std_logic_vector(MFB_REGIONS*max(1,log2(MFB_REGION_SIZE))-1 downto 0)
in
RX_MFB_EOF_POS
std_logic_vector(MFB_REGIONS*max(1,log2(MFB_REGION_SIZE*MFB_BLOCK_SIZE))-1 downto 0)
in
RX_MFB_SOF
std_logic_vector(MFB_REGIONS-1 downto 0)
in
RX_MFB_EOF
std_logic_vector(MFB_REGIONS-1 downto 0)
in
RX_MFB_SRC_RDY
std_logic
in
RX_MFB_DST_RDY
std_logic
out
RX_OFFSET
std_logic_vector(MFB_REGIONS*OFFSET_WIDTH-1 downto 0)
in
Header offset from SOF POS, valid with SOF.
RX_LENGTH
std_logic_vector(MFB_REGIONS*LENGTH_WIDTH-1 downto 0)
in
Header length, valid with SOF.
RX_CHSUM_EN
std_logic_vector(MFB_REGIONS-1 downto 0)
in
Enable checksum calculation, valid with SOF.
=====
TX MVB STREAM
=====
Calculated checksums.
TX_MVB_DATA
std_logic_vector(MFB_REGIONS*16-1 downto 0)
out
The calculated checksum.
TX_MVB_META
std_logic_vector(MFB_REGIONS*MFB_META_WIDTH-1 downto 0)
out
TX_CHSUM_BYPASS
std_logic_vector(MFB_REGIONS-1 downto 0)
out
Bypass checksum insertion (=> checksum caluculation is not desired).
TX_MVB_VLD
std_logic_vector(MFB_REGIONS-1 downto 0)
out
TX_MVB_SRC_RDY
std_logic
out
TX_MVB_DST_RDY
std_logic
in