1.2.3. Embedded UEFI firmware volume

PH11 of xbl_a.bin (file 0x7e7a0, vaddr 0x9FC00000, 0x240000 bytes) is one EDK2 firmware volume (EFI_FIRMWARE_FILE_SYSTEM2 GUID 8c8ce578-8a3d-4f1c-9935-896185c32dd3). Its top level holds only three payload files: a SEC_CORE, a FREEFORM (the uefiplat.cfg platform config — Platform config (uefiplat.cfg)), and one FV_IMAGE whose GUIDed section is gzip-compressed (magic 1f8b08 at file 0xbb368). Decompressing it yields the real DXE volume — 5.75 MB, 114 FFS files: one DXE_CORE, 82 drivers, 29 freeform config/resource blobs, one application, one pad.

1.2.3.1. The 82 DXE drivers

Names from their PE debug paths — the full set of hardware and service drivers XBL stands up before launching the boot app:

Dispatch / runtime:

DxeCore, QcomBds, DevicePathDxe, SecurityStubDxe, RuntimeDxe, CapsuleRuntimeDxe, ResetRuntimeDxe, VariableDxe, EnvDxe, EmbeddedMonotonicCounter, MetronomeDxe, WatchdogTimer, QcomWDogDxe, MinidumpTADxe, ULogDxe

Storage / filesystem:

UFSDxe, SdccDxe, PartitionDxe, DiskIoDxe, Fat, FvSimpleFileSystem, FvDxe, UsbMsdDxe

Clocks / power / thermal:

ClockDxe, RpmhDxe, CPRDxe, NpaDxe, RscRtDxe, CmdDbDxe, LimitsDxe, TsensDxe, PwrUtilsDxe, AdcDxe

PMIC / charger:

PmicDxe, ChargerExDxe, QcomChargerApp, QcomChargerDxeLA, UsbPwrCtrlDxe

Security / crypto / TrustZone:

TzDxe, ScmDxe, VerifiedBootDxe, SecRSADxe, HashDxe, CipherDxe, ASN1X509Dxe, MacDxe, RngDxe, ShmBridgeDxe, FeatureEnablerDxe, SCHandlerRtDxe

CPU / arch / interrupt / timer:

ArmCpuDxe, ArmGicDxe, ArmTimerDxe, QcomMpmTimerDxe, PdcDxe, HWIODxeDriver, ChipInfo, PlatformInfoDxeDriver

Buses / IO / IOMMU:

I2C, SPMI, GpiDxe, DALSys, DALTLMM, HALIOMMU

USB:

UsbDeviceDxe, UsbfnDwc3Dxe, UsbConfigDxe

Display / console / HII:

DisplayDxe, GraphicsConsoleDxe, FontDxe, EnglishDxe, SimpleTextInOutSerial, ConSplitterDxe, ConPlatformDxe, HiiDatabase, PrintDxe

Buttons:

ButtonsDxe

Image loading (PIL):

PILDxe, PILProxyDxe — load/authenticate the secure-world and coprocessor images (TZ/HYP/AOP/modem/dsp)

Memory:

DDRInfoDxe

Coprocessor:

ADSPDxe, SmemDxe, VcsDxe, RealTimeClock

Notable presences: PILDxe/PILProxyDxe are how XBL brings up the secure world (Boot chain and exception-level hand-off (PBL → XBL → ABL)); VerifiedBootDxe + TzDxe + ScmDxe are the AVB/Keymaster plumbing ABL consumes (AVB enforcement code path (LoadImageAndAuth / libavb)); UFSDxe/PartitionDxe are the EFI_BLOCK_IO/GPT providers a UEFI-resident payload inherits (Below UEFI — execution state and hardware register surface); QcomBds is the dispatcher that launches LinuxLoader (XBL → ABL hand-off contract (bounded)).

Source:

_READONLY/lun1/xbl_a.bin — gzip DXE FV at file 0xbb368 decompressed to 5.75 MB / 114 FFS; driver names read from PE debug paths.

Cross-refs:

XBL (segment layout), Platform config (uefiplat.cfg) (the uefiplat.cfg FREEFORM file in this same FV), XBL → ABL hand-off contract (bounded).