Although TI are a lot more forthcoming with datasheets they will still hold back information on things like the DSP core inside an ARM SoC. So you get DSP based codecs as binary blobs and no information on how to target the DSP yourself. And then further up, in the same family, you'll get a similar processor that *does* have an accessible DSP core... but you have to pay for the privilege in chip cost (and it only makes sense to do that if you actually need that feature).
Then again, as you said, TI are good at letting you buy small amounts of these chips as well as devkits so it makes sense for most of the information about the chip to be accessible. There's no chance of going to Farnell and buying one of these Broadcom processors.