<br><br><div class="gmail_quote">On Thu, Mar 4, 2010 at 7:26 PM, Chris Tyler <span dir="ltr"><<a href="mailto:chris@tylers.info">chris@tylers.info</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">On Thu, 2010-03-04 at 12:04 -0600, Adam Miller wrote:<br>
</div><div class="im">> RAM is a really good point, I think it will be in the ballpark of 256<br>
> (plus or minus a bit). Also, I'd like to open up the conversation<br>
> about version of ARM we as a SIG want to support as the efforts start<br>
> to ramp up while targeting popular devices. I think ARMv9 might be a<br>
> little too aggressive but are there any devices that are still<br>
> prominent that are ARMv5? Would it be possible (or even feasible) to<br>
> maintain ARMv5, ARMv7, and ARMv9 in parallel and treat them as<br>
> separate architectures?<br>
<br>
</div>The ARM "Family" vs. "Architecture" numbering is wonky (and very<br>
frustrating - larger numbers don't reliably mean newer, bigger, faster,<br>
or better). The SheevaPlug uses an "ARM9E" family chip, which uses the<br>
"ARMv5TEJ" architecture. ARMv5 is a needed current target for that<br>
device and others.<br>
<br>
However, the popular Cortex chips use ARMv6M and ARMx7* architecture. Is<br>
there enough performance difference to warrant targeting both<br>
independently? And just the kernel, or userspace as well?<br>
<div><div></div><div class="h5"><br></div></div></blockquote><div><br></div><div>I'd been pondering Adam's exact question. It seems that Ubuntu (not that we should or need to follow what they do) decided upon supporting ARMv7 and later at their UDS [1]. There's also some other points here [2]. They also discussed a number of other worthwhile points to do with device trees and bootloaders which I presume are all relevant for discussions about support of Fedora on ARM platforms. But generally I've ignorant about the pros and cons of supporting the different artchitectures and I know there's discussion over THUMB vs no THUMB compile options as well. </div>
<div><br></div><div>Peter</div><div><br></div><div>[1] <a href="http://lwn.net/Articles/364654/">http://lwn.net/Articles/364654/</a> </div><div>[2] <a href="https://wiki.ubuntu.com/Mobile/ARMv7AndThumb">https://wiki.ubuntu.com/Mobile/ARMv7AndThumb</a></div>
</div>