Aint13

Index: 0223 | Size: 4,608 bytes (9,216 body) | Phase: DXE

Overview

UEFI DXE driver providing legacy INT 13h disk I/O service compatibility for AHCI/SATA controllers. Discovers AHCI mass storage controllers via PCI I/O protocol, enumerates attached block devices (ATA and ATAPI), and wires them into real-mode INT 13h dispatch infrastructure. Parses MBR/EBR partition tables for CHS geometry optimization and programs INT 13h vector tables into legacy BIOS real-mode memory. Supports up to 8 disks with both native ATA and ATAPI (CD/DVD) devices.

Key Functions

• _ModuleEntryPoint -- DXE entry: saves globals, calls sub_18FC, installs protocol interface with sub_624 callback.
• sub_624 -- Module init: PCI enumeration via PciIo protocol, memory allocation, timer registration (88ms).
• sub_18BC -- ASSERT/debug helper used in entry/init validation.
• sub_18FC -- HOB table initialization helper.
• sub_1634 -- Chipset-specific INT 13h vector programming (AInt13Csp.c split file).
• sub_10CC -- Core dispatcher: opens PCI bridge, locates chipset-specific protocols, calls geometry setup per disk.
• sub_BD4 -- Per-disk geometry setup: 42-byte descriptor builder.
• sub_A50 -- ATA geometry extraction from identify data.
• sub_86C -- MBR/EBR CHS geometry adjustment.
• sub_794 -- CHS geometry calculation helper.
• sub_E88 -- INT 13h handler registration record builder.
• sub_52C -- Timer callback that reprograms chipset INT13h vectors.
• sub_480 -- PCI/ATA device enumeration helper.
• sub_17F4 -- Lazy debug protocol acquisition.
• sub_1874 -- Conditional debug print helper.
• sub_19D4 -- CMOS debug-level fetch.
• sub_1A24 -- GUID compare helper.
• sub_1A94 -- Unaligned 64-bit read helper.

Module split

• Aint13.c contains module entry/recovery scaffolding.
• AInt13Csp.c contains platform chipset behavior, including sub_1634 and hardware programming details.

Recovered Variables

• mImageHandle
• mSystemTable
• mBootServices
• mRuntimeServices
• mAint13ProtocolGuid
• byte_2149 (mAint13InitDone)
• n8_2148 (mAint13DiskCount)
• psub_624 (mModuleProtocolThunk)
• qword_2140 (mInt13VectorTableBase)
• dword_21C0 (mPciMmrAddress)

Protocols/Dependencies

• PCI I/O Protocol (B2FA4764-...), UEFI Boot Services
• Chipset-specific protocol A (DB9A1E3D-...) for PCI bridge config
• CMOS/RTC I/O (ports 0x70/0x71) for debug level

Platform

Intel Purley (Xeon Scalable), HR650X -- AMI AmiModulePkg/AHCI/Aint13/