Boot BIOS Straps (BBS): This field determines the destination of accesses to the
BIOS memory range. The default values for these bits represent the strap values of
GNT0# (bit 11) and SPI_CS1# (bit 10) at the rising edge of PWROK.
Bits 11:10Description
0xb SPI
10b PCI
11b LPC
When PCI is selected, the top 16MB of memory below 4GB (FF00_0000h to
FFFF_FFFFh) is accepted by the primary side of the PCI P2P bridge and forwarded to
the PCI bus. This allows systems with corrupted or unprogrammed flash to boot from
a PCI device. The PCI-to-PCI bridge Memory Space Enable bit does not need to be set
(nor any other bits) in order for these cycles to go to PCI. Note that BIOS decode
range bits and the other BIOS protection bits have no effect when PCI is selected.
When SPI or LPC is selected, the range that is decoded is further qualified by other
configuration bits described in the respective sections.
The value in this field can be overwritten by software as long as the BIOS Interface
Lock-Down (bit 0) is not set.
Цитата:
GNT4#, GNT5# - это контакты Grant PCI?
угу. Только они мультиплексируются еще с GPIO, да еще к тому же и юзаются в качетве страпов
Цитата:
Интересно, а как быть в этом случае, если не все слоты на плате распаяны?
BSV
на ICH7 и ICH8...
Bits 11:10 Description
0xb SPI
10b PCI
11b LPC
When PCI is selected, the top 16MB of memory below 4GB (FF00_0000h to
FFFF_FFFFh) is accepted by the primary side of the PCI P2P bridge and forwarded to
the PCI bus. This allows systems with corrupted or unprogrammed flash to boot from
a PCI device. The PCI-to-PCI bridge Memory Space Enable bit does not need to be set
(nor any other bits) in order for these cycles to go to PCI. Note that BIOS decode
range bits and the other BIOS protection bits have no effect when PCI is selected.
When SPI or LPC is selected, the range that is decoded is further qualified by other
configuration bits described in the respective sections.
The value in this field can be overwritten by software as long as the BIOS Interface
Lock-Down (bit 0) is not set.
угу. Только они мультиплексируются еще с GPIO, да еще к тому же и юзаются в качетве страпов
см. выше, да, кстати, GNT5 у ICH8 нету.