CS5535-UDCF AMD (ADVANCED MICRO DEVICES), CS5535-UDCF Datasheet - Page 173

• Manufacturer Part Number: CS5535-UDCF
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of CS5535-UDCF

• Operating Temperature (min): 0C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

Power Management Control
5.17.2.1 ACPI System Power States
• G0/S0: Not Sleeping. Software is executing code or
• G1/S1: Requires explicit software action to enter this
• G1/S3: Save-to-RAM state. Requires explicit software
• G1/S4: Suspend-to-Disk state. Requires explicit soft-
• G2/S5: Requires explicit software action to enter this
• G3: Software action is not required to enter this state.
5.17.2.2 CPU Power States
• G0/S0/C0: Processor actively executing instructions and
• G0/S0/C1: HLT instruction executed. Usually occurs in
• G1/S1/C2: Processor is in the lowest power state that
AMD Geode™ CS5535 Companion Device Data Book
could be halted waiting for a system event.
state. All Geode GX processor, Geode CS5535
companion device, and main memory states main-
tained. All system clocks may be turned off except 32
kHz or selected additional clocks may be left on as
required. The PMC provides generic controls SLEEP_X
and SLEEP_Y that may be used to control the “D” states
of external system devices (not described in this data
book, see ACPI specification for details). Two additional
internal signals control PCI and IDE input and outputs. A
wakeup event brings the system back to the opcode
following the one that initiated entry into S1. Context
restore operation is not required on the Geode GX
processor, Geode CS5535 companion device, or main
memory.
action to enter this state. The Geode CS5535
companion device and other system context are lost.
System state is saved in the main memory. To properly
support this state, main memory power must be
controlled by WORKING power while the Geode
CS5535 companion device, Geode GX processor, and
all other system components power must be controlled
by WORK_AUX power. Note that this applies only to the
Working domain of the Geode CS5535 companion
device. The Standby domain must be continuously
supplied from Standby power.
ware action to enter this state. Same as S3 state, but the
system state is “saved” on the hard drive or other mass
storage device. Only Standby power is on while in this
state.
state. All system context is lost and not saved. Oper-
ating system re-boot is required. The 32 kHz clock is
kept running for Standby PMC and selected GPIO and
MFGPT circuits.
Working power and Standby power are removed. The
only domain that may be powered is the RTC. It is not a
requirement that the RTC be powered.
clock running. Cache snoops supported.
the Operating System’s idle loop. Operating System
waiting for Power Management Event (PME), interrupt,
or ASMI. Cache snoops are supported while in this
state, so bus mastering activity can safely occur.
maintains context in a software invisible fashion.
Entered as part of the S1 sequence. The
5.17.2.3 Hardware Power States
• FO (Full On): From a hardware reset, all clocks come
• AHCG (Active Hardware Clock Gating): This is the
• Suspend on Halt: See CPU power state G0/S0/C1.
• Sleep: See CPU power state G1/S1/C2.
• Auto-refresh: The memory controller issues an auto-
5.17.2.4 PMC Control
Under S3, S4, and S5 power management states, all
Working domain circuits, as well as the Geode GX proces-
sor, are turned off to conserve power. Under S3, the sys-
tem memory is powered by V
refresh mode but otherwise, all other system components
are also turned off.
The PMC is used to establish overall system power states.
Normally, the Standby domain voltages are present any-
time the system is plugged into the wall; if portable, any-
time the battery is plugged in. Generally, G3 Mechanical
Off (see Table 5-34 on page 172) only applies during stor-
age or maintenance. Therefore, operationally speaking, the
PMC Standby controller is always available to manage
power. There is a class of system designs that do not
require G1 and G2 global power states. These systems
usually power-up WORKING and STANDBY power
domains simultaneously when power is applied.
For supporting “Save-to-RAM” (G1/S3) the WORKING out-
put is used to switch off/on the Working domain sources for
system memory while the WORK_AUX output is used to
switch off/on the Working domain sources for everything
else. Thus, the PMC can completely control the system
power states via these outputs.
SUSP#/SUSPA# signaling protocol indicates entry.
SUSP# is not an explicit external signal, it is part of the
CIS packet. (See Section 5.2.14 "CPU Interface Serial
(CIS)" on page 87 for further details.) No explicit soft-
ware action required. However, this state can be
entered by explicit software action by reading the ACPI
P_LVL2 register provided by the Geode GX processor’s
GLCP.
up Full On or always running. Generally, the system
should not be left in this state. The AHCG state should
be used.
desired mode of operation; it utilizes automatic hard-
ware clock gating. Latency to turn on a clock is near 0.
This hardware state should be established at system
initialization by BIOS code; after initialization it needs no
additional support. AHCG is invisible to the Operating
System, ACPI, or other software based power manage-
ment facilities.
refresh command to the DRAMs. In this state, the
DRAMs perform refresh cycles on their own without any
additional commands or activity from the memory
controller or the interface. As long as power to the
DRAMs is maintained, the memory contents are
retained.
31506B
IO_VSB
in Standby Auto-
173