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PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
PM7341 S/UNI-IMA-84
DATASHEET
PMC-2000223
ISSUE 4
INVERSE MULTIPLEXING OVER ATM
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
361
12.4.3 Configuring For IMA Operations
All IMA timeouts are programmable. In general, the default values result in ~1
sec timeouts with a 55 MHz SYSCLK.
The global IMA interrupt enables default to disabled. In an interrupt driven
system, these interrupt should be selectively enabled in registers 0x218, 0x21A,
and 0x21C.
RIPP_EN in Register –x200 controls whether internal IMA state machines engine
is enabled. This must be set for proper operation.
IMA groups are configured using the following per group tables:
RIPP Group Configuration Record
: Group options and configuration,
TIMA TX-LID-to-Physcial-Link Mapping Table: maps Group Tag/LID to
physical Link.
TIMA TX Group Configuration Record
: maps group to Any-PHY/UTOPIA
port ID, sets stuffing mode and OAM label.
RDAT IMA Group Context Record
: maps group to Any-PHY/UTOPIA port ID
and also the following per link tables:
RIPP TX Link Configuration Record
: maps physical Link to Group Tag/LID,
enables TX Link Interrupts.
RIPP RX Link Configuration Record
: maps physical Link to Group Tag,
enables RX link interrupts
TIMA TX Physical Link Context Record: sets ICP offset.
RDAT Link Context Record
: maps physical link to group.
12.4.3.1
Configuring a Group for IMA
IMA groups within the S/UNI-IMA-84 are identified by a “group tag”. The group
tag is an identifier with values from 0 to 41 that uniquely identifies the group for