SystemACE bootloader for PowerPC on Virtex4 FX

hi, me Antti

yes I wrote some systemace loader that I tested on ML300 loooong time ago some derivate of that is still in use. wasnt very good one, the FAT support was really really minimal :(

there should be no problems fitting into brams, but better look at the dosfs that is very small and support FAT pretty completly, changing the sector read for systemace should not be a problem

antti I may be able to dig out some of my old code, buts its rather nasty

It is fairly straightforward to use xilfatfs (shipped with EDK) to load a file from the CF into memory and transfer control to the loaded program. Just use open/read file library calls.

/Siva

Hi Siva,

Yep, but a bog standard implementation (i.e. just using the standard library code) is going to be 20kB+. I don't have that many block RAMs to play with, so want to create something as small as possible.

Cheers, Jon

Jon,

assuming that you are using System ACE CF to configure your Virtex-4 FX device you can load the boot code directly into the processor caches which gives you 16KB of instruction and 16KB of data space. That's enough for the bootloader you describe and you do not even need a single BRAM.

- Peter

J> Hi Siva,

dosfs claims to be Hi Siva,

Peter,

Yep.

Thanks sounds very interesting. Any pointers or app notes on how to do this? (Sorry if I'm overlooking the obvious)

Cheers, Jon

Hi Antti,

Do you have a link to this particular implementation? Is it open source? (I have googled, but it seems there are lots of different dosfs')

Cheers, Jon

"Jon Beniston" schrieb im Newsbeitrag news: snipped-for-privacy@j33g2000cwa.googlegroups.com...

learn too google :)

its simple

google larwe dosfs

Antti

"Jon Beniston" schrieb im Newsbeitrag news: snipped-for-privacy@i40g2000cwc.googlegroups.com...

xil appnotes and ref designs

pretty cool they use the USR ACCESS JTAG command to create virtual JTAG TAP master that then connects to the PPC JTAG tap and uses PPC ICE registers to load the caches. was pretty cool to see that implementation

look at the ultracontroller II, the thing is all there

antti

See XAPP575, XAPP807, XAPP719, and XAPP571 for more information about UltraController-II and some of the underlying technology.

However, the problem here is much simpler, i.e. a regular EDK design where the code is loaded into the PPC405 caches through proper setup of the linker script and the ACE options file (more details later today).

- Peter

Antti Lukats wrote:

Ah, if you has said search for dosfs by Lewin Edwards, I'm sure I would have got it. Thanks anyway!

Compiling all of dosfs for PowerPC seems to be about 8kB. To read a file using the systemace drivers comes to a total of about 10kB.So quite a nice saving. Thanks.

Cheers, Jon