Specifications

228 AMD Geode™ GeodeROM Functional Specification
System Management Mode Software
32087C
15.12 Events
The main routine of all VSMs is a message handling loop. When an event occurs, the VSM(s) registered for that event are
sent a MSG_EVENT message with the event code in Parameter0. Other parameters may also be passed, depending on
the event. A VSM is only sent a MSG_EVENT message for the events that it registered as a handler.
15.12.1 EVENT_GRAPHICS
This event is sent when there is an SMI from the graphics unit. The parameters are only valid for trapped I/O, not asynchro-
nous graphics events.
Parameter1
Flags field (from SMM header)
Parameter2
Bits [31:16] = Data Size field from SMM header
Bits [15:0] = I/O address from SMM header
Parameter3
Data (if I/O write)
Parameter4
Memory address if string I/O
15.12.2 EVENT_VBLANK
A vertical blank interrupt has occurred.
No Parameters
Table 15-7. Events
Event Meaning
EVENT_GRAPHICS VGA I/O access, text buffer access, or vertical retrace
EVENT_VBLANK
1
1. Geode GX1 processor only. Not applicable to Geode GX processor and later processors.
Vertical retrace SMI
EVENT_AUDIO
1
Audio event
EVENT_USB USB event
EVENT_ACPI The ACPI timer expired
EVENT_ACPI_TIMER
1
The ACPI timer expired
EVENT_IO_TRAP I/O trap
EVENT_IO_TIMEOUT I/O timeout
EVENT_MEMORY_TRAP
1
Memory trap
EVENT_MEMORY_TIMEOUT
1
Memory trap timeout
EVENT_VIDEO_INACTIVITY Video inactivity timer expired
EVENT_GPIO GPIO transition
EVENT_SOFTWARE_SMI Software SMI
EVENT_PCI_TRAP PCI trap
EVENT_TIMER A millisecond timer expired
EVENT_VIRTUAL_REGISTER Virtual register access
EVENT_A20 A change in the A20 mask has occurred
EVENT_NMI
1
An NMI has occurred.
EVENT_GT1
1
General Purpose Timer 1 has expired