[PATCH 0/5] Enable Qi / avoiding re-introducing "hidden variable"

[Werner Almesberger]

Andy Green wrote:
> The fact they aren't afraid of it isn't really telling us it is
> "generally useful for production device" though.

Are we targetting the fetters and shackles faction now ? I thought
they were happy enough with the iPhone ;-)

> It leaves open
> different kernels and so on, but we can nuke them too and then our
> situation is deterministic.

Same applies for the boot parameter line. Call it /boot/uImage.param
if you want, then you can  rm /boot/uImage.*

> Obviously there is no technical difficulty to do it for NAND or SD.  I
> am trying to avoid the whole class of behaviour-changing variable hidden
> in the device though.

It's exactly as much hidden or not as the kernel proper.

The problem with how these things are with u-boot is that they live
in different domains, e.g., it's hard to access or even change the
boot parameter line from the kernel. It's actually sufficiently
messy to do even within u-boot. No surprise this causes problems.

> Is there any benefit to that?

Less knowledge about how the system is supposed to behave in qi.
In GTA03, this would basically reduce it to only a small set of
devices with a standard configuration. (Yep, you're right, I2C
has there as well.) Maybe 2/3 of the GPIOs can remain at their
reset default.

So when we move GPIOs around in the future, you don't need to
add yet another board variant to qi, only because something has
changed that qi doesn't care about anyway.

- Werner