EP80579 Datasheet, PDF (1086/1916 Pages) Intel Corporation – Intel® EP80579 Integrated Processor Product Line

Intel^® EP80579 Integrated Processor
(RSMRST# goes high), the PWRBTN# signal is already high (because V_CC-standby
goes high before RSMRST# goes high) and the PWRBTN_STS bit is 0.
2. RI#: RI# does not have an internal pull-up. Therefore, if this signal is enabled as a
wake event, it is important to keep this signal powered during the power loss
event. If this signal goes low (active), when power returns the RI_STS bit is set and
the system interprets that as a wake event.
3. RTC Alarm: The RTC_EN bit is in the RTC well and is preserved after a power loss.
Like PWRBTN_STS the RTC_STS bit is cleared when RSMRST# goes low.
CMI monitors both PWROK and RSMRST# to detect for power failures. If PWROK goes
low, the PWROK_FLR bit is set. If RSMRST# goes low, PWR_FLR is set. Software can
clear PWR_FLR by writing a 1 to that bit
Although PME_EN is in the RTC well, this signal cannot wake the system after a power
loss. PME_EN is cleared by RTEST#, and PME_STS is cleared by RSMRST#.
Table 27-34. Transitions Due To Power Failure
State at Power
Failure
S0, S1, S3
S4
S5
AFTERG3_EN bit
1
0
1
0
1
0
Transition When Power Returns
S5
S0
S4
S0
S5
S0
The power failure bit (PWR_FLR) is set after any power failure. Software can clear it by
writing a 1 to that bit.
The CPUPWR_FLR bit separately reports power failures that result in VRMPWRGD going
inactive.
27.7
Processor Thermal Management
CMI has several mechanisms to assist with managing thermal problems in the system.
27.7.1
PROCHOT# Signal for SMI# or SCI
The PROCHOT# signal is used as a status input from a thermal sensor. The sensor
could be inside the processor or in a separate component near the processor. CMI
follows these behaviors with regard to the PROCHOT# signal:
1. Based on the PROCHOT# signal going active, CMI generates an SMI# or SCI
(depending on SCI_EN).
2. If the PROCHOT_POL bit is set low, when PROCHOT# goes low, the PROCHOT_STS
bit will be set. This is an indicator that the thermal threshold has been exceeded. If
the PROCHOT_EN bit is set, then when PROCHOT_STS goes active, either an SMI#
or SCI# will be generated (depending on the SCI_EN bit being set). The power
management software (BIOS or ACPI) can then take measures to start reducing
the temperature. Examples include shutting unneeded subsystems, or halting the
processor.
3. By setting the PROCHOT_POL bit to high, another SMI# or SCI# can optionally be
generated when the PROCHOT# signal goes back high. This allows the software
(BIOS or ACPI) to turn off the cooling methods.
Intel^® EP80579 Integrated Processor Product Line Datasheet
1086
August 2009
Order Number: 320066-003US