Broadcom NetXtreme/NetLink BCM5718 Series User Manual

IOV – Transmit SideBCM5718 Programmer’s Guide
Broadcom®
January 29, 2016 • 5718-PG108-R Page 267
Figure 53: IOV Receive Flow
IOV – Transmit Side
Transmit enhancement for IOV involves adding multiple Host Send Rings or effectively adding multiple transmit
queues. At present, Feb 2009, only Netqueue is capable of utilizing multiple TX queues whilst VMQ is not.
Although, the Transmit Side Scaling (TSS) feature of NDIS 6.x is capable of using multiple transmit queues. This
is the reason this feature, namely 16 Send Rings, could be enabled in BCM5718/19/20 irrespective of the IOV-
Mode settings.
BCM5718/19/20 shall implement a limited set of capabilities in this regard:
• A maximum of 16 Send Rings (SBD Rings)
• Multiple Send Rings could be enumerated only in conjunction to either IOV-Mode or RSS Mode
• All 16 Send Rings may be enabled in conjunction of IOV Mode
• Up to 4 Send Rings may be enabled in conjunction of RSS Mode
Jumbo RX BD
Producer Rings
x17
Standard RX BD
Producer Ri ngs
x17
Return
BD Rings
x17
Host Memory
RX Buffers
RDMA
Engine
Per
Queue
RBD
Cache
RX-MBUF
sBD Prod Index
Ring #00
sBD Prod Index
Ring #16
jBD Prod Index
Ring #00
jBD Prod Index
Ring #16
RX EMAC
VRQ Filters
VRQ #
Frame
Header
WDMA
Engine
Receive
Queue
PCIe Link
Sawtooth
Chip
RBD Fetch
Req
RBD
Data
Packet data
Write
Return BD
Write
M
B
U
F
C
l
u
s
t
e
r
P
o
i
n
t
e
r
C
h
a
i
n
o
f
M
B
U
F
s
Fr ame-Header
[ VRQ # ]
Place Frame In RX-MBUF
Drop-VRQ
(Discard
Packets )
Per -Q
Stats
RX
Wires
Post
RX
Buffers
RX Packet
Producer
MailBoxes
17 + 17

Broadcom NetXtreme/NetLink BCM5718 Series Specifications

General

Brand	Broadcom
Model	NetXtreme/NetLink BCM5718 Series
Category	Controller
Language	English