RE: fsl-dcu not works on latest "drm-next"

From: Meng Yi
Date: Wed May 25 2016 - 04:58:45 EST


Hi Alexander,

> From: Alexander Stein [mailto:alexander.stein@xxxxxxxxxxxxxxxxxxxxx]
> Sent: Wednesday, May 25, 2016 4:32 PM
> To: Stefan Agner <stefan@xxxxxxxx>
> Cc: Meng Yi <meng.yi@xxxxxxx>; dri-devel@xxxxxxxxxxxxxxxxxxxxx; David Airlie
> <airlied@xxxxxxxx>; airlied@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Mark
> Brown <broonie@xxxxxxxxxx>
> Subject: Re: fsl-dcu not works on latest "drm-next"
>
> On Tuesday 24 May 2016 23:20:02, Stefan Agner wrote:
> > On 2016-05-24 19:14, Meng Yi wrote:
> > > I found that its regmap endianness issue, so I want to replace the
> > > "regmap".
> > Hm, replace with what? Note that we need some kind of endianness
> > convertion since the IP is big endian on LS1021a and little endian on
> > Vybrid (vf610).
>
> Yep, regmap is required and was broken meanwhile but should be fixed now.
> See linked lkml post.
>
> > Is it maybe just an issue with regmap/the big-endian property in the
> > device tree? Maybe this thread is interesting for you:
> > https://lkml.org/lkml/2016/3/23/233
>
> AFAICT device tree should not been changed here. The "big-endian" property
> was there fromt he beginning.
>
> > > I just tested the latest drm-next branch on Freescale/NXP
> > > ls1021a-twr, and got some log below. And fsl-dcu not works.
> > >
> > > Since "drm-next" merged some branch , use git bisect had some
> > > problem ,
> > >
> > > so I manually checked out that "fsl-dcu" works at
> > > d761701c55a99598477f3cb25c03d939a7711e74
> > >
> > > And not works now. some log below:
>
> Which commit actually broke your kernel? And where to fetch it from? Is your
> problem really caused by regmap?

Since there are lots of merge commit, I had manually debugged that issue. And yes, it is caused by regmap.
I fetched the kernel from git://people.freedesktop.org/~airlied/linux

Best Regards,
Meng Yi