Open PS2 Loader Extended APA

Open PS2 Loader Extended APA is an experimental Open PS2 Loader fork that keeps the PlayStation 2's APA/PFS internal-HDD environment while extending game storage beyond the traditional single 32-bit APA bank.

It is the companion OPL build for PS2 HDD Manager when formatting an internal HDD larger than 2 TiB using Extended APA / banked APA mode.

Important

For ordinary APA HDDs up to 2 TiB, use the official Open PS2 Loader unless you specifically need Extended APA support. A >2 TiB Extended APA disk must be prepared by a compatible formatter/writer.

Hardware-tested status

The first release has been validated on real PlayStation 2 hardware with a 4 TB HDD:

• FHDB / FreeHDBoot boot: working
• Bank 0 game scan + launch: working
• Bank 1 game scan + launch: working
• OPL artwork/config stored in Bank 0 and used by Bank 1 games: working
• Conventional APA/PFS system area retained in Bank 0: working

The exact loader code used for that hardware test is commit:

b2e39f0d6b569cf79a3235dc47050016d102cd31

How Extended APA works

A large HDD is divided into independent APA banks. Each bank continues to use ordinary bank-relative 32-bit APA addresses; OPL adds the bank base when accessing the physical disk.

flowchart TB
    HDD[Physical PS2 HDD]

    HDD --> B0[Bank 0<br/>base 0x000000000<br/>bootable APA/PFS]
    HDD --> B1[Bank 1<br/>base 0x100000000<br/>games-only APA]
    HDD --> B2[Bank 2+<br/>base N × 0x100000000<br/>games-only APA]

    B0 --> SYS[FHDB / PFS / OPL data / ART / CFG / APPS]
    B0 --> G0[HDL games]
    B1 --> G1[HDL games]
    B2 --> G2[HDL games]

Loading

The physical address translation is:

bank_base_lba = bank_index * 0x100000000
physical_lba  = bank_base_lba + relative_lba

With 512-byte logical sectors, one full bank spans exactly 2 TiB:

0x100000000 sectors × 512 bytes = 2 TiB

Bank 0 remains conventional and contains FHDB, normal PFS system/application data, OPL configuration, artwork and optionally games. Bank 1+ are games-only APA banks.

For the full technical explanation, examples and compatibility model, see EXTENDED_APA.md.

First release

v1.2.0-Beta-2273-Extended-APA-1

The attached ELF is the exact CI-produced binary from the successful Bank 0 + Bank 1 hardware test. The release includes a SHA-256 checksum so tools such as PS2 HDD Manager can pin and verify the known-good build instead of silently following development HEAD.

Intended setup path

The normal workflow is:

PS2 HDD Manager
      ↓
select Extended APA for >2 TiB HDD
      ↓
create conventional Bank 0 + games-only Bank 1+
      ↓
install FHDB / OPL data into Bank 0
      ↓
download and install the pinned Open PS2 Loader Extended APA release
      ↓
install HDL games into Bank 0 or upper banks

All artwork, apps and OPL configuration remain in Bank 0 and are shared by games discovered in the upper banks.

Relationship to upstream OPL

This project is based on Open PS2 Loader by the OPL contributors. The Extended APA changes are focused specifically on preserving APA/PFS while adding bank-aware HDD game enumeration and launch support above 2 TiB.

Upstream project: https://github.com/ps2homebrew/Open-PS2-Loader

For standard OPL documentation, normal releases and general compatibility information, use the upstream repository.

License and credits

Copyright 2013, Ifcaro & jimmikaelkael and Open PS2 Loader contributors.

Licensed under the Academic Free License version 3.0. See LICENSE and CREDITS.

Extended APA work and hardware testing maintained by VajskiDs / L10N37.