On Sun, Jul 31, 2011 at 01:37:46AM +0200, Linus Walleij wrote:

2011/7/31 Russell King - ARM Linux [off-list ref]:

quoted

On Sun, Jul 31, 2011 at 12:32:55AM +0200, Linus Walleij wrote:

quoted

The PL08x has two bus mastering interfaces. They can be
connected to two separate busses and two adress spaces
even, usually that is not the case though.

This is not what the function is about... that's done by my
pl08x_select_bus() function.

To be clear, I was explaining what I percieved as a
question from Viresh about what the comment in this hunk of
the patch was about:

Yes, and the comment and function name are wrong for what it's doing.
I repeat: it has nothing to do with selecting an AHB bus.

As for the LLI code, all of it's weird complexity comes from the fact
that the DMAC cannot let a single element pass across 1KB (0x400)
boundaries, which is one more than a little insane hardware
restriction, and I have no clue where that limitation actually comes
from, likely strange VHDL code.

Viresh's discussion with ARM Ltd indicates that this is not the case,
and that restriction comes from misunderstanding of the documentation.