IBM POWERPC 750GL - Manual (Page 336)

User’s Manual
IBM PowerPC 750GX and 750GL RISC Microprocessor
Power and Thermal Management
Page 336 of 377
gx_10.fm.(1.2)
March 27, 2006
Figure 10-1. 750GX Power States
Table 10-1. 750GX Microprocessor Programmable Power Modes
Power
Management
Mode
Functioning Units Activation Method Full-Power Wake Up Method
Full on All units active — —
Doze
• Bus snooping
• Data cache as needed
• Decrementer timer Controlled by software
External asynchronous exceptions 1
Decrementer interrupt
Performance-monitor interrupt
Thermal-management interrupt
Hard or soft reset
Nap
• Bus snooping (enabled by deas-
sertion of QACK)
• Decrementer timer
Controlled by hardware and software
External asynchronous exceptions
1
Decrementer interrupt
Hard or soft reset
Sleep None Controlled by hardware and software
External asynchronous exceptions*
Hard or soft reset
1. Exceptions are referred to as interrupts in the architecture specification.
Full
On
Doze Sleep
T1
T2
T3 T4
Nap
T5
T6
T7
T8
allow
snoop
T1: HID0(Doze) = 1 and MSR(POW) 0 → 1
T2: HRESET, SRESET, INT, SMI, MCP, DEC, PFM, machine-check interrupts, thermal-management interrupt
T3: HID0(Nap) = 1 and MSR(POW) 0
→ 1
T4:HRESET, SRESET, INT, SMI, MCP, DEC
T5: HID0(Sleep) = 1 and MSR(POW) 0
→ 1
T6: HRESET, SRESET, INT, SMI, MCP
T7: QACK 0
→ 1
T8: QACK 1 → 0