As it seems, Marvell has released the PXA310 and PXA320 developer manuals. They can now be downloaded and used by anyone, without a need for a NDA. This is great, as it removes one major obstacle for Free Software developers to write code (e.g. Linux kernel / driver code) for those System on a chip (SoC) devices. Marvell also re-released the PXA27x manuals, but this is of less significance considering that back when the PXA was still with Intel, Intel had the full manuals public.
Ti has done something similar, at least for the OMAP3530: Publicly releasing their Technical Reference Manual without any requirement for an NDA. Sure, it is only one of their many products. But I think they have been showing progress even on one of the older OMAP24xx product, as far as I remember.
Now the only major vendor of ARM SoC's for mobile handheld devices like smartphones that has currently no reference manuals public is Samsung. This is really sad, as their S3C2410/2440 manuals always used to be publicly available from their website. Now the S3C6400 and S3C6410 manuals are under NDA, effectively preventing anyone to develop Open Source (and specifically Linux) code for their systems. I sincirely hope they understand what a competitive disadvantage they are now facing in the Linux market.