cn8237 Mindspeed Technologies, cn8237 Datasheet - Page 37

• Manufacturer Part Number: cn8237
• Description: Atm Oc-12 Servicesar Plus With Xbr Traffic Management
• Manufacturer: Mindspeed Technologies

CN8237
ATM OC-12 ServiceSAR Plus with xBR Traffic Management
Figure 2-1. Multiple Client Architecture Supports Up To 32 Clients (Peers)
2.2.2 CN8237 Queue Structure
28237-DSH-001-C
PCI Motherboard
PCI Cards
Logical
Physical
Physical
Logical
Client
Client
Client
Client
architecture, the CN8237 supplies the synchronization between asynchronous
tasks requiring ATM services.
figure shows that clients can be multiple applications in a shared memory, or
separate physical entities. All communicate directly with the CN8237.
The flow of the reassembly, scheduling, and segmentation processes in the
CN8237 is monitored, coordinated, and controlled through the use of a full array
of circular queues, serviced by the CN8237 or the host.
descriptors to the CN8237 for segmentation. The segmentation coprocessor then
processes these transmit queue entries as part of the segmentation function.
coprocessor and read by the segmentation coprocessor. The queue includes data
on OAM PM cells to be transmitted and as data on ABR-class received
Backward_RM and Forward_RM cells. The RSM/SEG queue is a private queue
for the SAR that the host cannot read or write.
Each client interfaces to the CN8237 independently. Due to its server
The following queues exist in local memory:
• Transmit queues (up to 32 queues)
• Reassembly/segmentation queue
• Free buffer queues (up to 32 queues)—includes the Global OAM free
Figure 2-2
Transmit queues are used by the host to submit chains of segmentation buffer
The reassembly/segmentation queue is written to by the reassembly
buffer queue.
Mindspeed Technologies
illustrates the location of each queue.
LEGEND:
2.2 High Performance Host Architecture with Buffer Isolation
CN8237 Subsystem
Figure 2-1
ATM Server
™
illustrates this client/server model. The
Host Data Path
Host Control/Status Flow
2.0 Architecture Overview
ATM
User-Network
Interface
8237_014
2-3