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G
Core Logic Module
(Continued)
2
GBL_RLS (Global Release). (Write Only)
This write only bit is used by ACPI software to raise an event to the BIOS soft-
ware (i.e., it generates an SMI to pass execution control to the BIOS).
0: Disable.
1: Enable.
This is a write only bit and reads of this bit always return a 0.
To generate an SMI, ACPI software writes the GBL_RLS bit which in turn sets the BIOS_STS bit (F1BAR1+I/O Offset
0Eh[0]) and raises a PME. For the PME to generate an SMI, set BIOS_EN (F1BAR1+I/O Offset 0Fh[0] to 1).
The top level SMI status is reported at F1BAR0+I/O offset 00h/02h.
Second level status is at F1BAR0+I/O Offset 22h[5].
BM_RLD (Bus Master RLD).
If the processor is in the C3 state and a bus master request is generated, force the processor
to transition to the C0 state.
0: Disable.
1: Enable.
SCI_EN (System Control Interrupt Enable).
Globally selects power management events (PMEs) reported in PM1A_STS
and GPE0_STS (F1BAR1+I/O Offset 08h and 10h) to be either an SCI or SMI type of interrupt.
0: APM Mode, generates an SMI and status is reported at F1BAR0+I/O Offset 00h/02h[0].
1: ACPI Mode, generates an SCI if the corresponding PME enable bit is set and status is reported at F1BAR1+I/O Offset
08h and 10h.
Note:
This bit enables the ACPI state machine.
1
0
Offset 0Eh
ACPI_BIOS_STS Register (R/W)
Reset Value: 00h
7:1
0
Reserved.
Must be set to 0.
BIOS_STS (BIOS Status Release).
When 1 is written to the GLB_RLS bit (F1BAR1+I/O Offset 0Ch[2]), this bit is also set
to 1.
Write 1 to clear.
Offset 0Fh
ACPI_BIOS_EN Register (R/W)
Reset Value: 00h
7:2
1
Reserved.
Must be set to 0.
BIOS_RLS (BIOS Release). (Write Only)
When this bit is asserted, allow the BIOS to release control of the global lock.
0: Disable.
1: Enable.
This is a write only bit and reads of this bit always return a 0.
To generate an SCI, the BIOS writes the BIOS_RLS bit which in turn sets the GBL_STS bit (F1BAR1+I/O Offset 08h[5]) and
raises a PME. For the PME to generate an SCI, set GBL_EN (F1BAR1+I/O Offset 0Ah[5] to 1).
BIOS_EN (BIOS Enable).
When this bit is asserted, allow SMI generation by ACPI software via writes to GBL_RLS
(F1BAR1+I/O Offset 0Ch[2]).
0: Disable.
1: Enable.
0
Offset 10h-11h
Notes:
GPE0_STS — General Purpose Event 0 PME/SCI Status Register (R/W)
This is the top level of PME/SCI status reporting. There is no second level except for bit 3 (GPIOs) where the next level of
status is reported at F0BAR0+I/O Offset 0Ch/1Ch.
Reset Value: xxxxh
1)
2)
If SCI generation is not desired, the status bits are still set by the described conditions and can be used for monitoring pur-
poses.
15:12
11
Reserved.
Must be set to 0.
Reserved.
Table 5-34. F1BAR1+I/O Offset: ACPI Support Registers (Continued)
Bit
Description