Status Block; Table 35: Status Block - Broadcom NetXtreme/NetLink BCM5718 Series Programmer's Manual

BCM5718 Programmer's Guide
Bit # Flag Name
9 CPU Post-DMA
10 HDRLEN[3]
11 HDRLEN[4]
12 HDRLEN[5]
13 HDRLEN[6]
14 HDRLEN[7]
15 Do Not Generate CRC

Status Block

The status block has been modified in order to accommodate the jumbo producer ring's consumer index.
The status block is a data structure in the host memory. The host driver uses this data structure to trace the
packet receive and transmission status and resource usage. Its length is 24 bytes. The driver needs to configure
the status block host address register to point to the physical address in host memory for this data structure.
The BCM5718 family will update the status block in host memory (via DMA) prior to a host coalescing interrupt
or MSI/MSI-X. The frequency of these status block updates is determined by the host coalescing logic. The two
status block update interrupt triggers are RX/TX coalescing timer and RX/TX maximum coalesced frame count
threshold.
A new field to indicate the Receive Jumbo Producer Ring Consumer Index is added to the BCM5718 family's
Legacy RSS mode status block. The updated structure of the status block is shown in
Note that there are multiple formats of status blocks.
31
Offset 16
0x00 Status Word
0x04 Reserved 0x0
0x08 Receive Standard Producer Ring Consumer
Index
0x0C Receive Return Ring 2 Producer Index
0x10 Send BD Consumer Index
0x14 Reserved 0x0
Broadcom
®
January 29, 2016 • 5718-PG108-R
Table 34: Send Buffer Descriptor Flags (Cont.)
Flag Description
If this bit is set, the CPU is required to act upon the buffer before the send
data completion state machine is kicked off. Alternately, if hardware LSO
is enabled and this bit is set in conjunction with CPU pre-DMA, then this
buffer is treated as part of an LSO segment to be further segmented by
hardware.
The length of the Ether+IP+TCP headers (combined) to be replicated in
each frame arising out of a large TCP segment (LSO).
Maximum Header Length could be 256B.
If set to 1, the controller will not append an Ethernet CRC to the end of
the frame.

Table 35: Status Block

15
Receive Return Ring 1 Producer Index
Receive Return Ring 3 Producer Index
Receive Return Ring 0 Producer Index
Receive Jumbo Producer Ring Consumer Index
Jumbo Frames
Table 35 below.
Status Tag[7:0]
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