DMA transfers controlled from userland

gauri · Post by **gauri** » Sun Mar 23, 2008 6:18 pm

Is it possible to do a DMA transfer from user code? It seems that DMA module is accessible only from kernel-land.
I need that for moving textures and V&I-buffers to VRAM. Please, do not suggest GU fransfers since they are a bit inconvenient for me.

moonlight · Post by **moonlight** » Sun Mar 23, 2008 8:18 pm

Well, sceDmacMemcpy and sceDmacTryMemcpy are the only functions provided to user mode. I would expect them to have the same parameters than a normal memcpy.

gauri · Post by **gauri** » Sun Mar 23, 2008 10:15 pm

And we get no chance to see if our transfer request has been fulfilled...
Can you point where sceDmacMemcpy is exported from? There's nothing on this in pspsdk.

moonlight · Post by **moonlight** » Sun Mar 23, 2008 10:23 pm

http://silverspring.lan.st/1.5x/kd/dmacplus.xml

It is the sceDmac library, the other is the kernel one.
It is not in pspsdk, you'll have to create a stub or a library.

gauri · Post by **gauri** » Sun Mar 23, 2008 10:30 pm

I'm using 3.x firmware... looks like these functions are no longer exported.
But, on the other hand, officially released software should still work with new firmwares. How do they manage to do that?

moonlight · Post by **moonlight** » Sun Mar 23, 2008 10:35 pm

They are still there:
http://silverspring.lan.st/3.7x/kd/lowio.xml

It is just that they merged a lot of lowlevel prx's into a single one back in 3.50, but the library names remain same.

gauri · Post by **gauri** » Sun Mar 23, 2008 11:07 pm

Oh, they really are. Thanks!

On the secont thought... How can I track whether the transfer completed or not? Do these calls block?