Datasheet

Interfaces
Intel
®
Xeon
®
Processor C5500/C3500 Series
Datasheet, Volume 1 February 2010
68 Order Number: 323103-001
Table 27. Thermal Throttling Control Fields (Sheet 1 of 2)
Register
Dynamically
Validated
Parameter Bits One per Description
MC_THERMAL_CONTROL THROTTLE_MODE 2 Channel
Defines the source of throttling
information to be DDR_THERM#
signal, virtual temperature sensor, or
Throttle_Now configuration bit.
Throttling can also be disabled with
this field.
MC_THERMAL_CONTROL THROTTLE_EN 1 Channel DRAM commands will be throttled.
MC_CLOSED_LOOP YES THROTTLE_NOW 4 Throttler
Throttle according to Min Throttle
Duty Cycle. This parameter may be
modified during operation.
MC_CLOSED_LOOP YES
MIN_THROTTLE_
DUTY_CYC
10 Channel
The minimum number of DCLKs of
operation allowed after throttling is 4x
this parameter. In order to provide
actual command opportunities, the
number of clocks between CKE de-
assertion and first command should
be considered. This parameter may be
modified during operation.
MC_THERMAL_PARAMS_B SAFE_DUTY_CYC 10 Channel
This value replaces Min Throttle Duty
Cycle if it has not been updated for 4
sample periods.
MC_THERMAL_PARAMS_B
SAFE_COOLING_
COEF
8Channel
Any rank that has received eight
temperature samples since the last
cooling coefficient update will load this
value.
MC_THERMAL_CONTROL APPLY_SAFE 1 Channel
If set, the Safe cooling coefficient will
be applied after eight temperature
sample intervals. Parameter appears
on B-x stepping silicon.
MC_CHANNEL_X_ZQ_TIMING ZQ_INTERVAL 21 Channel
This field defines the sample interval,
formerly used for on-die temperature
sensor samples, but currently only
used to apply failsafe values when it
has been too long between updates.
Nominally set to 128 ms.
MC_THERMAL_DEFEATURE
THERM_REG_LO
CK
1Channel
Prevents further modification of all
parameters in this table. This should
not be set if parameters are to be
modified during operation.
On A-x stepping, unless set, safe
cooling coefficient and DutyCycle will
be applied when the associated
register is not updated for 4 sample
intervals. In the long run, safe cooling
coefficient will be enabled by the
APPLY_SAFE bit.
MC_THERMAL_PARAMS_A RDCMD_ ENERGY 8 Channel
Energy of a read including data
transfer
MC_THERMAL_PARAMS_A WRCMD_ENERGY 8 Channel
Energy of a write including data
transfer
MC_THERMAL_PARAMS_A
CKE_DEASSERT_
ENERGY
8 Channel
Energy of having CKE de-asserted
when no command is issued.
MC_THERMAL_PARAMS_A
CKE_ASSERT_EN
ERGY
8Channel
Energy of having CKE asserted when
no command is issued
MC_THERMAL_PARAMS_B
ACTCMD_ENERG
Y
8 Channel Energy of an Activate/Precharge Cycle