Sd Card Booting

[danieljacobs]

I think i remember reading somewhere that it was possible to boot off an SD card?
Is this actually possible? It would be great cos then we wouldn't have to worry about bricking our GP2Xs when updating the firmware.

Or is it possible to access the NAND memory directly? 'Cos when i plug the GP2X into my computer, it only recognises the SD card.

 

[craigix]

You might have read about something called 'HH' that is in part what you are talking about, its being worked on, things like a raw SD driver had to be written (and an SDK based on the GP32 GCC setup). Its reaching the final stages.

Infact the alternative firmware flasher is HH.

 

[tekt5]

does gp2x have anything like GPBios?

it lets you automatically boot off a firmware image or .fxe file from your smc

 

[Squidge]

By default, the 2X will only ever boot from nand, and it does that pretty badly, but it works. Hopefully the alternative firmware will mature soon, and this will allow far more features.

 

[judge0]

Yes it's possible (without HH) to boot from SD card.
Standard U-Boot install( which GP2X is NOT) looks for several filenames on varied media. Two are reserved for alternate OS image (not flash upgrade) and instant-run hardware coded app.
Scanning through the archives GPH has released, it appears GPH has at least renamed image filenames (*.bin/*.gu), at most(worst scenario) disabled support for the above items.
Information for above taken from U-Boot Manual/Faq.

At this time it isn't to apparent whether GPH has released their source for U-Boot. It would be needed to work further. However, with the amount of bricking going on, I'd say we'd be better off to scrap GPH's implementation completely.

Go HH team, go . . .

 

[danieljacobs]

At this time it isn't to apparent whether GPH has released their source for U-Boot. It would be needed to work further. However, with the amount of bricking going on, I'd say we'd be better off to scrap GPH's implementation completely.

GPH have released the U-boot source, it's here: http://archive.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,46,932

So, what are your thoughts now......?

 

[judge0]

At this time it isn't to apparent whether GPH has released their source for U-Boot. It would be needed to work further. However, with the amount of bricking going on, I'd say we'd be better off to scrap GPH's implementation completely.

GPH have released the U-boot source, it's here: http://archive.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,46,932

So, what are your thoughts now......?

​

That is the MagicEyes source

 

[DJWillis]

GPH have released the U-boot source at it's here: http://archive.gp2x.de/cgi-bin/cfiles.cgi?0,0,0,0,46,932

​

That it's not what's on the GP2X , it's the baseline MMSP2 code not the GP2X code, it is completely missing SD support and does not support the GP2X's LCD (so no 1st boot screen, not that it matters).

It will work on retail GP2X's but you can't use it to flash the NAND like the GP2X U-Boot does (somewhat badly).

Also, flashing U-Boot is the best way to brick your device so you may want to consider that .

I did start to play with upgrading that base code to the latest version of U-Boot but as I don't have working jTAG I am not testing the results on my device just yet .

Adding SD support using the SDK2X/HH SD driver and replicating the GPH flash/upgrade functionality is not that hard (in theory) and once you have SD support booting this and that off SD is an easy enough job to do .

 

[karmacop911]

I would really love to be able to boot a small SD card directly, just like popping a game into a gameboy. And what a rush it would be to be able to test your OWN programs this way. GPH should implement this as a standard feature!

 

[Squidge]

GPH should implement this as a standard feature!

​

They did, although it didn't work as well as they'd hoped, so they named it "InstaBrick"

Personally, I think we should ask GPH to do as little low-level coding as possible, and let them just work on the menu and stuff, and leave the low level stuff to the professionals h34r:

(specially since they don't seem to want to share there kernel patches with us )