ps1: bundle plain-ELF POPS loader + KEYS.BIN (iPoPS, MIT)

Fix 80020148 'game could not be started' on ARK-5: the base PBP's encrypted
~PSP loader fails to link on modern CFW. Use the bundled plain-ELF loader
(data/loader/DATA.PSP) as the DATA.PSP section instead, and write the 16-byte
NPDRM version key (data/loader/KEYS.BIN) alongside the EBOOT so CFW can
decrypt the STARTDAT PGD. Both assets are from iPoPS (MIT, attributed).

- load_data_psp: prefer the bundled ELF, fall back to the base ~PSP loader.
- load_keys_bin: return the bundled 16-byte key when present.
- convert: write KEYS.BIN next to the output EBOOT.
- README + data/loader/ATTRIBUTION.md: document the loader and its license.

README.md

@@ -93,9 +93,10 @@ Discs are matched by hash first (most precise), then serial, then filename.
 - `data/covers/` — checked-in assets: the UMD video/game cover templates,
   `libretro-index.json` + `openvgdb-index.json` catalogs, `libretro-covers.zip` +
   `openvgdb-covers.zip` offline cover bundles, and the legacy cover cache.
-- `data/base.PBP` — a PSN PS1 classic EBOOT (any game) used as the encrypted
+- `data/base.PBP` — a PSN PS1 classic EBOOT (any game) supplying `STARTDAT`
-  loader when converting PS1 discs to `EBOOT.PBP` (git-ignored, copyrighted).
+  + a base `PARAM.SFO`/icon for PS1 conversion (git-ignored, copyrighted).
-  Prefer a 6.60/6.61-era classic; 3.xx-era loaders can fail on modern CFW.
+- `data/loader/DATA.PSP` + `data/loader/KEYS.BIN` — bundled plain-ELF POPS
+  loader and NPDRM version key (from iPoPS, MIT).
 - State dir (`~/.local/state/psp-preserve/` by default, or `$XDG_STATE_HOME/psp-preserve`):
   - `library.sqlite` — the catalog + library database.
   - `covers/` — downloaded cover cache.
@@ -189,16 +190,18 @@ PS1 discs (pending) and converted EBOOTs also show up in the **Library** tab
 - **Serial detection** — reads `SYSTEM.CNF` to derive the game ID (e.g.
   `SLUS-00001`) and writes it into `PARAM.SFO` + the PSAR header.
 - **base.pbp** — conversion needs a PSN PS1 classic `EBOOT.PBP` (any game) to
-  supply Sony's encrypted `DATA.PSP` loader (POPS emulator) and `STARTDAT`.
+  supply the `STARTDAT` block (boot logo + PGD) and a base `PARAM.SFO`/icon.
   Copy one to `data/base.PBP` and point **Settings → General → PS1 base.pbp**
-  at it. **Prefer a 6.60/6.61-era classic**: very old 3.xx-era classics ship a
+  at it. Any PS1 classic works structurally — the converter finds `STARTDAT`
-  POPS loader that fails to link on modern CFW (`80020148` "game could not be
+  at `PSAR + p1` regardless of PSAR alignment.
-  started"). Any PS1 classic works structurally — the converter finds
+- **POPS loader** — the `DATA.PSP` section uses a bundled plain-ELF loader
-  `STARTDAT` at `PSAR + p1` regardless of PSAR alignment.
+  (`data/loader/DATA.PSP`, from iPoPS, MIT) so the EBOOT boots on modern CFW
-- **Output** — a folder `<out>/<Game ID>/` containing a single `EBOOT.PBP`
+  without the base PBP's encrypted loader failing to link (`80020148`). The
-  (the popstation way: raw-DEFLATE-compressed PSAR, no `KEYS.BIN`/`DOCUMENT.DAT`),
+  base PBP's own loader is only used as a fallback when the bundle is missing.
-  ready to copy to `<PSP>/PSP/GAME/<Game ID>/`. Compatible with CFW POPS
+- **Output** — a folder `<out>/<Game ID>/` containing `EBOOT.PBP` (raw-DEFLATE
-  (ARK-4/ARK-5).
+  compressed PSAR) plus a `KEYS.BIN` (NPDRM version key used to decrypt the
+  `STARTDAT` PGD), ready to copy to `<PSP>/PSP/GAME/<Game ID>/`. Compatible
+  with CFW POPS (ARK-4/ARK-5).
 
 Configure the folders in **Settings → General** (or `PSP_PS1_ROOTS` /
 `PSP_PS1_OUTPUT_DIR`). Current limits: single-disc games only (no multi-disc

app/ps1_convert.py

@@ -15,11 +15,13 @@ Format reference (offsets are byte-exact):
                     b"PSISOIMG0000", game id at +0x400, TOC at +0x800,
                     ISO block index at +0x4000, disc data at +0x100000.
 
-A ``base.pbp`` (any PSN PS1 classic ``EBOOT.PBP``) is REQUIRED to supply two
+A ``base.pbp`` (any PSN PS1 classic ``EBOOT.PBP``) supplies the blobs that we
-blobs that we cannot synthesise:
+cannot synthesise:
 
-    * DATA.PSP  - the encrypted POPS loader (header section 8).
     * STARTDAT  - the trailing encrypted block (boot.png + PGD).
+    * DATA.PSP  - fallback only: the encrypted POPS loader, used when the
+                  bundled plain-ELF loader (``data/loader/DATA.PSP``, from
+                  iPoPS/MIT) is unavailable.
 
 Without a base.pbp the resulting EBOOT will not boot on real hardware; the
 converter refuses to run without one.
@@ -82,6 +84,14 @@ INDEX_ENTRY_SIZE = 32    # offset u32 + length u32 + 6 unused u32
 
 SYNC_PATTERN = b"\x00\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\x00"
 
+# Bundled plain-ELF POPS loader + NPDRM key (from iPoPS, MIT). Modern CFW
+# (ARK/PRO/ME) loads this ELF directly as the DATA.PSP section, sidestepping
+# the base PBP's encrypted ~PSP loader which frequently fails to link on
+# 6.60/6.61 (error 80020148 "game could not be started").
+_LOADER_DIR = Path(__file__).resolve().parent.parent / "data" / "loader"
+BUNDLED_DATA_PSP = _LOADER_DIR / "DATA.PSP"
+BUNDLED_KEYS_BIN = _LOADER_DIR / "KEYS.BIN"
+
 # SFO field formats (PSP PARAM.SFO).
 FMT_U32 = 0x0004
 FMT_STRING = 0x0204
@@ -518,6 +528,25 @@ def extract_data_psp(base_pbp: Path) -> bytes:
     return section[:prx_size]
 
 
+def load_data_psp(base_pbp: Path) -> bytes:
+    """Return the POPS loader (DATA.PSP) to embed.
+
+    Prefers the bundled plain-ELF loader (MIT, from iPoPS), which modern CFW
+    can load without ~PSP decryption. Falls back to the base PBP's encrypted
+    ~PSP loader when the bundle is absent.
+    """
+    if BUNDLED_DATA_PSP.is_file():
+        return BUNDLED_DATA_PSP.read_bytes()
+    return extract_data_psp(base_pbp)
+
+
+def load_keys_bin() -> Optional[bytes]:
+    """Return the bundled NPDRM version key (KEYS.BIN), if available."""
+    if BUNDLED_KEYS_BIN.is_file():
+        return BUNDLED_KEYS_BIN.read_bytes()
+    return None
+
+
 def extract_startdat(base_pbp: Path) -> bytes:
     """Extract the trailing STARTDAT block (boot.png + PGD) from a base PBP.
 
@@ -865,7 +894,7 @@ def convert(
         disc = DiscImage(None, source)
 
     # Resources required from the base PBP.
-    data_psp = extract_data_psp(base_pbp)
+    data_psp = load_data_psp(base_pbp)
     startdat = extract_startdat(base_pbp)
     _warn_old_base(base_pbp)
 
@@ -933,6 +962,13 @@ def convert(
         except OSError:
             pass
         raise
+
+    # Write the NPDRM version key next to the EBOOT (the popstation/iPoPS
+    # convention; ARK and other CFW read it to decrypt the STARTDAT PGD).
+    keys = load_keys_bin()
+    if keys is not None:
+        out_path.with_name("KEYS.BIN").write_bytes(keys)
+
     return out_path
 
 
@@ -948,9 +984,9 @@ def convert_to_folder(
 ) -> Path:
     """Convert a PS1 disc into a game folder ready for /PSP/GAME.
 
-    Writes ``<out_dir>/<GAME_ID>/EBOOT.PBP`` — the same single-file output the
+    Writes ``<out_dir>/<GAME_ID>/EBOOT.PBP`` plus a ``KEYS.BIN`` (the NPDRM
-    popstation tool produces. No KEYS.BIN or DOCUMENT.DAT is written:
+    version key modern CFW uses to decrypt the STARTDAT PGD). No
-    popstation doesn't emit them and CFW (ARK-4 POPS) doesn't need them.
+    DOCUMENT.DAT is written; CFW (ARK POPS) doesn't need one.
     """
     folder_name = re.sub(r"[^A-Za-z0-9]", "", game_id).upper() or "PS1GAME"
     folder = Path(out_dir) / folder_name

data/loader/ATTRIBUTION.md

@@ -0,0 +1,30 @@
+# Loader assets
+
+The files in this directory are bundled from [iPoPS](https://github.com/julianxhokaxhiu/iPoPS)
+by Julian Xhokaxhiu, licensed under the MIT License:
+
+- `DATA.PSP` — a plain-ELF PSP POPS loader (relocatable PRX, 19002 bytes).
+- `KEYS.BIN` — a 16-byte NPDRM version key used by CFW to decrypt the
+  `STARTDAT` PGD.
+
+MIT License
+
+Copyright (c) 2020 Julian Xhokaxhiu
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
+of the Software, and to permit persons to whom the Software is furnished to do
+so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

data/loader/KEYS.BIN

@@ -0,0 +1 @@
+MB\Ω:���� �"