82583V Datasheet, PDF (132/374 Pages) Intel Corporation – Intel® 82583V GbE Controller

82583V GbE Controller—Inline Functions
Case A: Using only an absolute timer
A bsolute Timer Value
PKT #1
PKT #2
PKT #3
PKT #4
Interrupt generated due to PKT #1
Case B: Using an absolute time in conjunction with the Packet timer
A bsolute Timer Value
A bsolute Timer Value
PKT #1
PKT #2
PKT #3
PKT #4
PKT #5
PKT #6
...
...
...
1) Packet timer expires
2) Interrupt generated
3) Absolute timer reset
Interrupt generalted (due to PKT #4)
as absolute timer expires.
Packet delay timer disabled untill
next packet is received and
transferred to host memory.
Case C: Packet timer expiring while a packet is transferred to host memory.
Illustrates that packet timer is re-started only after a packet is transferred to host memory.
A bsolute Timer Value
A bsolute Timer Value
PKT #1
PKT #2
PKT #3
PKT #4
PKT #5
PKT #6
...
...
...
1) Packet timer expires
2) Interrupt generated
3) Absolute timer reset
Interrupt generalted (due to PKT #4)
as absolute timer expires.
Packet delay timer disabled untill
next packet is received and
transferred to host memory.
Figure 32.
Packet and Absolute Timers
• Small Receive Packet Detect (ICR.SRPD)
— A receive interrupt is asserted when small-packet detection is enabled (RSRPD
is set with a non-zero value) and a packet of (size < RSRPD.SIZE) has been
transferred into the host memory. When comparing the size the headers and
CRC are included (if CRC stripping is not enabled). CRC and VLAN headers are
not included if they have been stripped. A receive timer interrupt cause
(ICR.RXT0) will also be noted when the small packet-detect interrupt occurs.
• Receive ACK frame interrupt is asserted when a frame is detected to be an ACK
frame. Detection of ACK frames are masked through the IMS register. When a
frame is detected as an ACK frame an interrupt is asserted after the
RAID.ACK_DELAY timer had expired and the ACK frames interrupts were not
masked in the IMS register.
Note:
The ACK frame detect feature is only active when configured to packet split
(RCTL.DTYP=01b) or the extended status feature is enabled (RFCTL.EXSTEN is set).
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