This method is only confirmed working on Windows and Mac OS for now.
Thanks to outreach by Reverie and work by SirMangler on File 1, and Fothsid on File 2, there is a method for emulator users to load faster without using HDD loading. The method uses Hostfs and a modified elf file to load the game files from a folder. This has a couple of benefits:
Note: This will be relevant for few people: If you have installed the games to your virtual HDD using the in-game install option, make sure to disable your virtual HDD in the PCSX2 settings. By default the game will boot using the official HDD Install, which makes this method non-functional, and attempting to switch to DVD mode in the game settings will freeze the game.
Macchina put together a newer file containing the modified files for both File 1 and File 2 covering the original Japanese language, English translation for use if you have applied the English Silent Hell translation patch to your ISO, and either standard 4:3 or widescreen patched for both.
Mount the ISO file of the game you wish to quickload.
In Windows, right click the ISO and select "Mount." The ISO contents will become mounted as a DVD and available in Windows Explorer as an inserted DVD.
In Mac OS, courtesy of Brandon Mooney: In Mac OS, open Finder. On the left side menu, select Applications. Scroll down and select Utilities. Select Disk Utility. On the top status bar, click File and select Open Disk Image. Navigate to where you have your ISOs and select which want you want to use first. Your ISO will now appear as “Untitled” on your desktop. Double-click it to reveal its contents.
Create a new folder for the game contents anywhere you would like. To make things easier, place this new folder in the same folder where you keep your PCSX2 game ISOs. Make sure to create separate folders for File 1 and File 2 if you will be quickloading both. Open the mounted DVD, select all contents from the DVD, and drag them into your new folder. Right click the virtual mounted DVD and click "Eject." On Mac OS, the file to right click is the file on the Desktop called "Untitled" created in Step 2.
Extract the game-specific SLPM_xxx.xx file from the zip archive you downloaded into the folder that you created, and overwrite the original. The name of the file depends on whether you are quickloading File 1 or File 2. Be sure to pick the correct file based on if you'd like the game to render in widescreen and if you have English patched your ISO.
Note: If you want to use the widescreen version, this will change the graphics during gameplay to widescreen. You will need to set PCSX2 to display in 16:9:
Open the Settings menu, click Graphics, and change Aspect Ratio to Widescreen (16:9).
Rename the SLPM file to add ".elf" to the end of the file name. E.g. for File 1, the name would become SLPM_654.28.elf
Configure PCSX2
Click System --> Emulation --> Enable Host Filesystem
If you created the file 1 or file 2 ISO contents folder where your other PCSX2 games are, you should be able to hit Settings > Scan for New Games. You should see an elf file
appear in the list, which will look different because the "Type" will appear as a gear, not a Disc:
If you do not see an entry with gear icon, right click on the game list, click Add Search Directory, double click on the folder where you put your File 1 or File 2 game contents - does not matter if you choose recursive or not, and then choose Select Folder. Select Settings > Scan for New Games. Do this again for either File 1 or File 2 if you have both.
Next, Right click on the elf entry in the game list, and select Properties.
Under Disc Path, select the Browse button and select the ISO file corresponding to the elf file, either File 1 or File 2.
Double click the elf entry in the game list.
You are now running the game from the files in your folder. Any changes you make to the files will only require you to re-run the SLPM_xxx.xx file.