Support header - data block boundary at symbol level (for g_symbol_w <= g_data_w) via g_symbol_w.

libraries/base/dp/src/vhdl/dp_offload_tx_v3.vhd

@@ -19,21 +19,25 @@
 --
 -------------------------------------------------------------------------------
 
+-- Author: D. van der Schuur, E. Kooistra
 -- Purpose:
--- . Concatenate a user-defined header to a DP frame e.g. to create an Ethernet frame
+-- . Concatenate a user-defined header to a data block e.g. to create an Eth
+--   frame
 -- Description:
--- . The header contents can be controlled dynamically by data path or MM control (selected by g_hdr_field_sel)
--- . The header and data can be concatened at symbol level. The g_symbol_w defines the
---   resolution of the empty field. The g_data_w must be an integer multiple of the 
---   g_symbol_w. If the empty field is not used or if the empty field is always 0 then
---   set g_symbol_w = g_data_w.
--- . For example to concat header and data for an Ethernet frame use:
+-- . The dp_offload_tx_v3 --> dp_offload_rx form a pair.
+-- . The header contents can be controlled dynamically by data path or MM
+--   control (selected by g_hdr_field_sel)
+-- . The header and data can be concatened at symbol level. The g_symbol_w
+--   defines the resolution of the empty field. The g_data_w must be an
+--   integer multiple of the g_symbol_w. If the empty field is not used or
+--   if the empty field is always 0 then set g_symbol_w = g_data_w.
+-- . For example to concat header and data block for an Ethernet frame use:
 --   - g_data_w = 32 (1GbE) or 64 (10GbE)
---   - g_symbol_w = c_byte_w = 8 if either the header or the data can have an
---                  non-zero empty field, so when they are not a multiple of 4 bytes
---                  (= 32b) or 8 bytes (= 64b).
---     g_symbol_w = g_data_w if the empty field is always 0, so the number of bits in
---                  the header and data are an integer number of g_data_w.
+--   - g_symbol_w = c_byte_w = 8 if either the header or the data block can
+--          have an non-zero empty field, so when they are not a multiple of
+--          4 bytes (= 32b) or 8 bytes (= 64b).
+--     g_symbol_w = g_data_w if the empty field is always 0, so the number of
+--          bits in the header and data are an integer number of g_data_w.
 
 
 LIBRARY IEEE, common_lib, technology_lib, mm_lib;
@@ -50,7 +54,7 @@ ENTITY dp_offload_tx_v3 IS
     g_nof_streams    : NATURAL;
     g_data_w         : NATURAL;
     g_symbol_w       : NATURAL;
-    g_hdr_field_arr  : t_common_field_arr; -- User defined header fields
+    g_hdr_field_arr  : t_common_field_arr;  -- User defined header fields
     g_hdr_field_sel  : STD_LOGIC_VECTOR;    -- For each header field, select the source: 0=data path, 1=MM controlled
     g_pipeline_ready : BOOLEAN := FALSE
   );