Regression: v4.0-rc1: iMX6: Hummingboard fails due to drivers/clk changes

[Fabio Estevam]

On Mon, Feb 23, 2015 at 8:27 PM, Russell King - ARM Linux
<linux at arm.linux.org.uk> wrote:
> On Mon, Feb 23, 2015 at 02:54:02PM -0800, Olof Johansson wrote:
>> On Mon, Feb 23, 2015 at 2:32 PM, Russell King - ARM Linux
>> <linux at arm.linux.org.uk> wrote:
>> > All,
>> >
>> > I just tried my SolidRun patch set on top of v4.0-rc1, and it fails to
>> > boot.  The kernel itself finishes booting, but it is unable to DHCP (for
>> > root-NFS) - nothing appears on the network.
>> >
>> > At first, I thought this would be a network driver bug, but reverting
>> > the mainline changes there didn't fix the regression.  Then I wondered
>> > if it was something in arch/arm/mach-imx, but no.
>> >
>> > When reverting all drivers/clk changes (and corresponding include/linux/*.h)
>> > between v3.19 and v4.0-rc1, I find that the regression is fixed.
>> >
>> > It seems that some CCF change is causing a regression somewhere in the
>> > clock tree on iMX6 CPUs.
>> >
>> > Unfortunately, without networking running, I can't dump the clock tree
>> > to find out what's different, and bisecting will be a major pain (needing
>> > each bisect point to be merged with my patch set, built and tested.)
>> >

> Bisect comes out with this commit as the culpret:
>
> commit 035a61c314eb3dab5bcc5683afaf4d412689858a
> Author: Tomeu Vizoso <tomeu.vizoso at collabora.com>
> Date:   Fri Jan 23 12:03:30 2015 +0100
>
>     clk: Make clk API return per-user struct clk instances
>
> Indeed, having the tree merged with af0f349b2996 works, then
> applying the above commit on top causes it to fail.

Tomeu, could you please take a look at this regression?