6.2 Firmware Volumes

Stage IV finalizes silicon initialization, adds basic operating system required interfaces, and supports minimally featured operating system boot. The new components are support in a dedicated firmware volume.

Name

Content

Compressed

Parent FV

FvOsBoot

DXE/BDS Services

Yes

None

FvLateSilicon

ACPI and SMM silicon support

No

FvOsBoot

Table 39 Stage IV Firmware Volumes

Which yields this example extension of the flash map for MMIO storage (add to Stage I + II + III map):

Binary

FV

Components

Purpose

Stage IV

FvOsBoot.fv

FvLateSilicon.fv (child FV)

​

​

​

Additional Components

Additional silicon initialization support that is performed late in the boot

​

​

AcpiTable.efi

Provides common ACPI services

​

​

PlatformAcpi.efi

Provides MinPlatform ACPI content

​

​

BoardAcpi.efi

Provides board ACPI content

​

​

PiSmmIpl.efi

SMM initial loader

​

​

PiSmmCore.efi

SMM core services

​

​

ReportStatusCodeRouterSmm.efi

SMM status code infrastructure

​

​

StatusCodeHandlerSmm.efi

SMM status code handlers

​

​

PiSmmCpu.efi

SMM CPU services

​

​

CpuIo2Smm.efi

SMM CPU IO services

​

​

FaultTolerantWriteSmm.efi

SMM fault tolerant write services

​

​

SpiFvbServiceSmm.efi

SMM SPI FLASH services

​

​

Additional Components

Additional post-memory components required for Stage IV boot

Table 40 Stage IV FV and Component Layout

See Appendix: Full FV Map for a more complete example Firmware Volume layout.