Freescale Semiconductor MPC8260 - Manual (Page 1148)

Inverse Multiplexing for ATM (IMA)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
33-46 Freescale Semiconductor
33.4.5.2.1 IMA Link Receive Control (ILRCNTL)
The fields of the ILRCNTL register are shown in Figure 33-24
Table 33-20 describes the ILRCNTL bit fields.
1
Boldfaced entries indicate parameters that must be initialized by the user. All other parameters are
managed by the microcode and should be initialized to zero unless otherwise stated.
0 1 2 3 4 5 7
Field GA SES TRL RXSC IGNUM
8 9 10 15
Field Add_new MON_ICP —
Figure 33-24. IMA Link Receive Control (ILRCNTL)
Table 33-20. ILRCNTL Field Descriptions
Bits Name Description
0 GA Group assigned flag. Set by software after group parameters have been validated.
0 Group unassigned.
1 Group assigned.
1 SES Severely errored seconds. Set by software when a severely errored second indication is
detected. When set, causes the receive stuff event counter and ICP violation counter to stop
counting.
2 TRL Identifies this link in the group as the Timing Reference Link (NOTE: Only one link per group
can be selected as the TRL).
3-4 RXSC Receive status/control. Sets the receive mode of the IMA link.
00 Filler mode. The IMA link processes only ICP cells. Data cells are replaced with filler cells.
01 Active mode. The IMA link is capable of receiving data cells.
10 Dropped. Must be set by the user during the process of dropping the link. Dropped links are
treated filler mode until they are switched out of the receive round-robin (i.e. data cells are
replaced with filler cells).
11 Reserved.
5-7 IGNUM Determines to which IMA group this link belongs. Contains the number of the link’s associated
IMA Group Table entry.
Note: This value need not be the same as the group’s IMA ID; the IMA ID is programmed
separately in the receive group’s RIMAID field.
8 ADD_NEW Identifies this link as a new/added link to a group. Software must flip (0 to 1 or 1 to 0) this bit
ONLY when adding a link to an existing group that is operational. If ADD_NEW =
ILRSTATE[ADD_NEW_M] = 0, set ADD_NEW to 1 to indicate this is an added link. If
ADD_NEW = ILRSTATE[ADD_NEW_M] = 1, set ADD_NEW to 0 to indicate this is an added
link. Initialize to zero.
9 MON_ICP Setting this bit will allow changed ICP cells received on this link to be passed on to the ATM
layer (defined channel). The user must monitor at least one link in order for ICP cells to be
passed on to the ATM layer.
10 - 15 — Reserved, initialize to zero.