Seagate Fibre Channel Interface - Manual (Page 50)

36 Fibre Channel Interface Manual, Rev. D
A buffer on the drive receives each of the following loop initialization frames: LISM, LIFA, LIPA, LIHA, LISA,
LIRP, and LILP. All other frames may be discarded if the L_Port’s buffer is full.
If the NL_Ports finds that there are not any more NL_Ports attached, but that there is only an F_Port or N_Port
attached, the NL_Port configures itself to operate as an N_Port by going into N_Port mode.
An L_Port begins the loop initialization procedure in the initializing state at the request of the node. In most
cases, the backpanel will be set to provide a hard assigned physical address which will not be changed by the
initialization process, unless duplicate hard assigned physical addresses are found. The AL_PA of the one
FL_Port (if present) is always 00h. All other AL_PA values will range from 01h - EFh.
Figure 10. Loop initialization sequences
Start_of_Frame delimiter (4 bytes)
Frame_Header (24 bytes)
SOFil
Cyclic Redundancy Check (4 bytes)
CRC
End_of_Frame delimiter (4 bytes)
EOFt
22xxxxxx
where ‘xxxxxx’ is hex ‘000000’ for an FL_Port and hex ‘0000EF’ for an NL_Port.
Payload (12, 20, or 132 bytes)
Loop
Initialization
Identifier*
8-byte Port_Name
*The loop initialization identifier is one of the following:
11010000h = LISM — Select master based on 8-byte Port_Name (12-byte payload with an 8-byte Port_Name)
11020000h = LIFA — Fabric Assigned AL_PA bit map (20-byte payload with a 16-byte AL_PA bit map)
LIFA is used to gather all fabric-assigned AL_PAs.
11030000h = LIPA — Previously-acquired AL_PA bit map (20-byte payload with a 16-byte AL_PA bit map)
LIPA is used to gather all previously-acquired AL_PAs.
11040000h = LIHA — Hard Assigned AL_PA bit map (20-byte payload with a 16-byte AL_PA bit map)
LIHA is used to gather all hard assigned AL_PAs (usually set with configuration jumpers
on the host backpanel).
11050000h = LISA — Soft Assigned AL_PA bit map (20-byte payload with a 16-byte AL_PA bit map)**
LISA is used to assign any remaining AL_PA bits.
11060000h = LIRP — Report AL_PA position map (132-byte payload with a 128-byte AL_PA position map)
LIRP is used to record the relative positions of all L_Ports on the loop.
11070000h = LILP — Loop AL_PA position map (132-byte payload with a 128-byte AL_PA position map)
LILP is used to inform all L_Ports of their relative positions on the loop
from the perspective of the loop master.
**LISA contains the AL_PA mapping field in byte 2 (01h) to indicate that all L_Ports are able to enter
their position into the LIRP AL_PA position map. The 01h value in byte 2 may be changed to 00h
to bypass the LIRP and LILP sequences.
00xxxxxx 01380000
16-byte AL_PA bit map
128-byte AL_PA position map (1-byte offset followed by up to 127 AL_PAs)
00000000 FFFFFFFF 00000000