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@@ -2036,6 +2036,24 @@ CBFS (Coreboot Filesystem) support
4th and following
BOOTP requests: delay 0 ... 8 sec
+ CONFIG_BOOTP_ID_CACHE_SIZE
+
+ BOOTP packets are uniquely identified using a 32-bit ID. The
+ server will copy the ID from client requests to responses and
+ U-Boot will use this to determine if it is the destination of
+ an incoming response. Some servers will check that addresses
+ aren't in use before handing them out (usually using an ARP
+ ping) and therefore take up to a few hundred milliseconds to
+ respond. Network congestion may also influence the time it
+ takes for a response to make it back to the client. If that
+ time is too long, U-Boot will retransmit requests. In order
+ to allow earlier responses to still be accepted after these
+ retransmissions, U-Boot's BOOTP client keeps a small cache of
+ IDs. The CONFIG_BOOTP_ID_CACHE_SIZE controls the size of this
+ cache. The default is to keep IDs for up to four outstanding
+ requests. Increasing this will allow U-Boot to accept offers
+ from a BOOTP client in networks with unusually high latency.
+
- DHCP Advanced Options:
You can fine tune the DHCP functionality by defining
CONFIG_BOOTP_* symbols: