BurstShort must be at least equal to the total LBUS width AND a multiple of 32 bytes. For a 512-bit segmented LBUS, BurstShort can be 64 bytes, 96 bytes, 128 bytes, and so on up to 256 bytes. BurstShort must always be less than or equal to BurstMax.
The Segmented LBUS in the TX core never violates the BurstShort value set by the
tx_ctl_burstshort input bus. However, more than the absolute
minimum required number of idle control words can be injected depending on the burst
size and which segment the burst ends. AMD requires
designing the transmitting scheduler so that burst sizes are always equal to BurstMax
except for the last two transfers of a packet (EOP and EOP-1).
The required value of BurstShort must be matched by the link partner.