Another Linux on ARM user (not OpenPandora)

[Cobalt60]

Hello everyone. I do not have an Open Pandora, but what I do have is a Toshiba AC100, which is a similar device. It has an Nvidia Tegra2 SoC with dual-core 1GHz Cortex-A9 and 333MHz 8-core ULV GeForce GPU. RAM is 512MB with 64MB used as VRAM. Display is 10" 1024x600@50Hz (no touch screen). My particular model has an 8GB internal eMMC and BlueTooth. This device is officially supported by Ubuntu as it is used as an ARM development platform for them. I am currently running Ubuntu 12.04, with Linux kernel 3.1.10-4.


I would like to use the device similarly to how an Open Pandora is intended to be used. I have been trying to get several emulators going. Ive had far more failures than success, and I was hoping those in the Open Pandora community would be willing to help out another Linux on ARM user. First I need to understand the differences between an Open Pandora and my system, so I have these fairly basic questions:


Does the Open Pandora use an armel or armhf architecture (or something else)? My AC100 is currently utilizing armhf.


Are PNDs the only package format used on an Open Pandora, or is it used in addition to a more conventional package format?


Would I be able to use PNDs on my setup?


Well thanks for any help.


-Chris P

 

[Linux-SWAT]

Hi !


OP is armel.


OP's OS is based on Angstrom Linux, and uses the opkg system.


.pnd won't run on your system because they are compiled for softfp.

 

[freamon]

CPU architecture is ARMv7a (Cortex-A8) - armel in Debian terms.


Pandora's hardware is lower-spec'd than yours and it's software (things like libc) is older (think Debian - Lenny). It's possible software written for Pandora would run on your device (assuming backwards-compatibility), but it seems equally likely that it wouldn't - especially for something as complicated and optimized as an emulator. You would probably be better off getting the source and compiling it (either on the device itself or cross-compiling for it)


The PND system is mostly just Python and Perl scripts I think, so you could get it up and running on your device, but it may be easier to loop-mount them as a squashfs file, and extract the contents. The pandora also understands the 'ipk' packaging format, but we don't use it for distributing as they install to then NAND memory (which is limited in size.)


Quick test for you though: try the attached file (unzip and run ./hello) - see what you get.

hello.zip

 

[overgauss]

.

 

[Binky]

^ would be an epic use of an old floppy disk box/holder

 

[Cobalt60]

OP is armel.


.pnd won't run on your system because they are compiled for softfp.

I guess I'll just have to keep compiling on my AC100. Ill probably do this in parallel to what is being done on the OP.

Pandora's hardware is lower-spec'd than yours

That may be so, but the 2 emulators I have running the best still leave a lot to be desired as far as frame rates. BTW, those 2 are DGen and FCEUX; both compiled on an AC100. Maybe I need to do a better job compiling.


Does the OP ever make used of GL-ES2 acceleration for emulators (or anything)?


Next Im going to see if I can compile PicoDrive and PSXreARMed as they seem well regarded here. Earlier today I spent almost 2 hours compiling snes9x, needing to setup an external hard disk as swap, and when it finished, it would not load any ROMs...

 

[mcobit]

GL-ES is used in some stuff like n64 emulation.


There are programs, like pcsxrearmed, that make good use of the neon instructions though.

 

[Cobalt60]

Unfortunately, the Tegra2 SOC disables NEON from the factory, no way to get it working.


I notice many emulators have an option for OpenGL acceleration. Has there been any effort to get these to use GL-ES2 instead? Do you know of emulators other than for the N64 that make use of GL-ES2?


Thanks for all the quick replies by the way!

 

[Linux-SWAT]

I think there's a plugin for PCSXReARMed.

 

[Cobalt60]

I just compiled PCSX-ReARMed on my AC100. Upon launching the program, I am presented with a message saying:

You don\t seem to have copied any BIOS files to <SD card>/pandora/pcsx_rearmed/b

If I start running OP programs on my AC100, would it be easiest for me to have an SD card with such folders on it? Or can I put the programs on an internal eMMC instead?


What can I do to make my AC100 more OP compatible? Keeping in mind that the OS will remain as Ubuntu and I will continue using armhf.

 

[freamon]

No - PCSX-ReArmed is just giving that message to be user-friendly to Pandora users (typically, PNDs are put on an SD-card in the /pandora/menu directory, and when the pnd is mounted by the system, is given read-write access to a folder on the SD card called /pandora/appdata/pcsx-re-armed.


In your case, SD cards or 'pandora' folders aren't required, just make a 'bios' directory in the root of the folder you're running pcsx-armed from and copy the playstation bios (you'll have to google it) into that folder.

 

[RichS]

Hi,


I'm another ac100 user, I have pcsxrearmed compiled and running (great job by the way). I fixed sound simply by realising it uses OSS and installing the Alsa OSS converter. Now my only issue is that the window is about 3 inches square, setting to fullscreen does nothing and none of the options for plugins seems to change it either. Am I missing something obvious, is there somewhere to set default resolution or pixel doubling?


Many thanks in advance,


Rich

 

[EvilDragon]

PCSXReARMed uses the hardware scaler of the OMAP3, as far as I know.


That might be the issue.

 

[notaz]

Yeah, normal Linux build doesn't have any kind of scaler yet..

 

[RichS]

Thanks for the replies guys, at least that explains what I'm seeing. I must admit to being out of my depth here, is the scaler cpu dependent, i.e. because ac100 is Tegra2 a specific scaler needs writing, or is there a chance that some generic code already exists and just needs working in to pcsx?


Cheers,


Rich

 

[notaz]

I don't know what's the best option here really. PSX resolution is almost variable (256-640 x 240-512), so some variable software scaler would probably work, but those are usually slow.


Another option is to use the video overlay, most platforms have those and they often have "free" scaling, but you have to convert to YUV color space which is slow thing to do too..


Third option is to use GLES for scaling, but texture streaming is also slow on some platforms.


Finally it's possible to use platform-specific scaler, like the one currently in use on pandora.


Ideal solution would be to provide all of above for user to choose, but that's hell lot of work. Hopefully at least some of those things will appear with time.

 

[RichS]

That's good to know. The great thing is that the emulator runs so smoothly at the moment, if someone could sort out a scaler it would be fantastic. Having had a look this is far beyond my current capabilities are there documents about how to do this sort of thing?

 

[notaz]

Ok I've pushed out a version with XVideo scaling, can anyone try it?

 

[Linux-SWAT]

A version of what ?

 

[notaz]

PCSX source, I'd like it to be tested on some ARM device that's not pandora and runs X.