
IBM3206K0424
IBM Processor for Network Resources
Preliminary
Buffer Pool Management (POOLS)
Page 268 of 676
pnr25.chapt04.01
August 14, 2000
13
Lock POOLs on Error
When set, this bit in conjunction with the lock mask will hold pools state machines in 
an idle state until cleared.
12
Packet High Priority on Get or 
Free FIFOs Full
When set, this bit causes pools to turn on its high priority request to Packet Memory 
when either the free or get FIFO is full.
11
Packet High Priority Always
When set, this bit causes pools to always use its high priority request to Packet Mem-
ory.
10
Control High Priority Always
When set, this bit causes pools to always use its high priority request to Control Mem-
ory.
9
Packet High Priority with Request 
Timer
When set, this bit causes pools to time the wait for Packet Memory service and when 
the timer expires move to high priority.
8
Control High Priority with Request 
Timer
When set, this bit causes pools to time the wait for Control Memory service and when 
the timer expires move to high priority.
7
Fast Free Mode
When this bit is set, Fast Free Mode is enabled. When pools is in Fast Free Mode it 
does not write out the buffer map with the modified control information that indicates 
that the map is unused. When in this mode unused buffer free error checking is dis-
abled.
6
Initialization Mode
When the value of the bit is 
’
0
’
, initialization mode is set. When the value is 
’
1
’
, opera-
tional mode is set. During initialization mode indexes are in the upper 16 bits of the 
data word. It is assumed that when initialization mode is on other normal operations 
are not active such as transmit or receive. During operational mode packet addresses 
assumed to be on the data bus.
5
Virtual Memory Mode
When set to 
’
0
’
, Virtual Memory mode is enabled. When set to 
’
1
’
, real memory mode 
is enabled.
4
Limit Event Generation
When set, this bit causes pools to limit the issuance of events to RXQUE when a 
GTD threshold, Total Threshold or POOL Threshold is reached. It will issue the first 
event and disable the related event enable bit. Software must then reset the bit if it 
wishes to see another such event. However, it is possible that events may be lost 
when this bit is set on.
3
Enable Event Interface
When set, this bit causes pools to issue resource events to RXQUE when a GTD 
threshold, Total Threshold or POOL Threshold is reached.
2
Enable Out of Range Index 
Checking
When set, this bit causes pools to check the indexes that are streaming by to be 
checked against a maximum value for that size index. If the normal initialization 
sequence is used, these maximum values will auto set.
1
Force All Queue Transactions to 
Memory
When set, this bit disables the internal tail to head transfer path within the queue. All 
indexes will proceed into memory before being brought to the head of the queue. This 
effectively preserves the operational history in memory. However, some caution is 
warranted since four full entries are required for a write to memory. This could cause 
indexes to get "stuck" at the back of the queue. When this residue occurs, a zero 
pointer is returned even though the operation might have otherwise returned a valid 
pointer.
0
Diagnostic Mode
When set, pools is in diagnostic mode. When cleared, pools is in normal mode. When 
in diagnostic mode, state machines are held in idle. If they are already active, when 
they next go to idle they will hold there.
Bit(s)
Function
Description