82371AB Datasheet, PDF (225/284 Pages) Intel Corporation – PCI-TO-ISA / IDE XCELERATOR PIIX4

E
82371AB (PIIX4)
11.3.5.12. Device 11: User Interface (Keyboard, Mouse, Video)
Device 11 monitors the system’s primary user interfaces, the keyboard, a PS/2 mouse, or the video
subsystem. It contains special logic to monitor the PCI bus utilization in order to detect video activity.
This will allow a system to playback video without power managing the video subsystem due to user
inactivity (no keyboard or mouse movement).
Device 11 System Events:
— PCI accesses to programmable linear frame buffer addresses, selectable below. The
linear frame buffer address consists of a 12-bit base address and 2-bit mask, allowing a
frame buffer address range from 1 Mbyte to 4 Mbytes. This can cause burst timer
reloads only.
— PCI accesses to VGA I/O addresses (3B0–3DFh) or the A and B segment video
memory ranges (A000–BFFFh). This can cause burst timer reloads only.
— PCI accesses to Keyboard Controller I/O addresses (60h, 64h). This can cause idle,
burst, or global standby timer reloads, IO trap SMI#, or forwarding KBC cycles to ISA.
— PCI bus utilization is monitored and a system event is generated if the number of PCI
data phases (as measured by FRAME# assertion) exceeds a set limit. This can cause
idle or global standby timer reloads.
— Assertion of GPI19. The polarity of active signal (high or low) is selectable. This can
cause idle, burst, or global standby timer reloads or IO trap SMI#.
— Assertion of IRQ1 or IRQ12/M. These can cause idle, burst, or global standby timer
reloads or IO trap SMI#.
Device 11 Linear Frame Buffer Ranges:
[LFB_DEC_EN]
Programmable Base Address:
[LFBASE_DEV11]
Programmable Mask:
[LFMASK_DEV11]
Device 11 VGA Decode:
[GRAPH_IO_EN]
Device 11 A,B Segment Decode:
[GRAPH_AB_EN]
Device 11 Idle Timer:
Resolution: 1 second or 1 minute
[IDL_SEL_DEV11]
Count: 5 bit
[IDL_CNTD]
GPI Enable:
[GPI_EN_DEV11]
GPI Polarity Select:
[GPI_POL_DEV11]
IRQ1 Enable:
[IRQ1_EN_DEV11]
IRQ12/M Enable:
[IRQ12_EN_DEV11]
KBC Decode Enable:
[KBC_EN_DEV11]
Device 11 ISA Forwarding Enable:
[KBC_EIO_EN]
PCI Bus Utilization Enable:
[VIDEO_EN]
[VIDEO_STS]
Threshold:
[BUS_UTIL]
Percent Active:
[%BUS_UTIL]
Device 11 Idle Timer Reload:
[IDL_EN_DEV11]
Global Standby Timer Reload:
[GRLD_EN_DEV11]
Burst Timer Reload (Fast Burst Only): [BRLD_EN_DEV11]
Idle Timer Expiration SMI#:
[IDL_EN_DEV11] [IDL_STS_DEV11]
Trap SMI#:
[TRP_EN_DEV11] [TRP_STS_DEV11]
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