Features
108
Quad-Core Intel® Xeon® Processor 5300 Series Datasheet
7.2.3
Stop-Grant State
When the STPCLK# pin is asserted, the Stop-Grant state of the processor is entered
20 bus clocks after the response phase of the processor issued Stop Grant
Acknowledge special bus cycle. The Quad-Core Intel® Xeon® Processor 5300 Series
will issue two Stop Grant Acknowledge special bus cycles, once for each die. Once the
STPCLK# pin has been asserted, it may only be deasserted once the processor is in the
Stop Grant state. All processor cores will enter the Stop-Grant state once the STPCLK#
pin is asserted. Additionally, all processor cores must be in the Stop Grant state before
the deassertion of STPCLK#.
Since the AGTL+ signal pins receive power from the front side bus, these pins should
not be driven (allowing the level to return to V
TT
) for minimum power drawn by the
termination resistors in this state. In addition, all other input pins on the front side bus
should be driven to the inactive state.
BINIT# will not be serviced while the processor is in Stop-Grant state. The event will be
latched and can be serviced by software upon exit from the Stop Grant state.
RESET# will cause the processor to immediately initialize itself, but the processor will
stay in Stop-Grant state. A transition back to the Normal state will occur with the de-
assertion of the STPCLK# signal.
Figure 7-1. Stop Clock State Machine
Extended HALT or HALT State
BCLK running
Snoops and interrupts allowed
Normal State
Normal execution
Extended HALT Snoop or HALT
Snoop State
BCLK running
Service snoops to caches
Stop Grant State
BCLK running
Snoops and interrupts allowed
Snoop
Event
Occurs
Snoop
Event
Serviced
INIT#, BINIT#, INTR, NMI, SMI#,
RESET#, FSB interrupts
STPCLK#
Asserted
STPCLK#
De-asserted
S
TP
C
LK
#
A
ss
er
te
d
S
TP
C
LK
#
D
e-
as
se
rte
d
Snoop Event Occurs
Snoop Event Serviced
HALT or MWAIT Instruction and
HALT Bus Cycle Generated
Stop Grant Snoop State
BCLK running
Service snoops to caches
Summary of Contents for Quad-Core Xeon
Page 1: ...Order Number 315569 003 Quad Core Intel Xeon Processor 5300 Series Datasheet September 2007...
Page 8: ...8 Quad Core Intel Xeon Processor 5300 Series Datasheet...
Page 54: ...Mechanical Specifications 56 Quad Core Intel Xeon Processor 5300 Series Datasheet...
Page 84: ...Signal Definitions 86 Quad Core Intel Xeon Processor 5300 Series Datasheet...
