4.13 (and probably all recent) kernels refuse to boot on one Nokia N950, work or another

Pali Rohár
2017-10-26T07:32:36Z

On Thursday 26 October 2017 09:27:59 Pavel Machek wrote:
> Hi!
>
> On Thu 2017-10-26 09:21:13, Pali Roh?r wrote:
> > On Thursday 26 October 2017 09:08:15 Pavel Machek wrote:
> > > On Thu 2017-10-26 08:25:02, Filip Matijevi? wrote:
> > > > Last time I couldn't get output on serial I used CONFIG_DEBUG_LL,
> > > > CONFIG_DEBUG_OMAP3UART3, CONFIG_EARLY_PRINTK... and ignore_loglevel
> > > > earlyprintk kernel params to get output early enough - I guess you
> > > > already tried that.
> > >
> > > I realized I'm not getting output from the decompessor (even on "S"
> > > machine), and enabled that.
> >
> > That is because you have not enabled those EARLY PRINK or DEBUG LL.
> > Similar thing is needed for N900 and IIRC in some of my linux-n900
> > branches I have config for it. Plus it needs patching some arch/arm
> > source files to make it working.
>
> Do you have a patch? That would be very useful.

Yes, in v4.9-n900 branch, see:
https://github.com/pali/linux-n900/commit/66b22ba4132ca90f7efc3f9e8ece8d4b9adddcdc

> Seems like debugging in uncompressor was broken some time ago:
>
> config DEBUG_UNCOMPRESS
> bool
> depends on ARCH_MULTIPLATFORM || PLAT_SAMSUNG || ARM_SINGLE_ARMV7M
> default y if DEBUG_LL && !DEBUG_OMAP2PLUS_UART &&
> (!DEBUG_TEGRA_UART || !ZBOOT_ROM)
> && \!DEBUG_BRCMSTB_UART
>
>
> > > But I'm _still_ not getting any output on decompressor... early
> > > printing works ok on "S" but not on "P".
> >
> > I guess there can be either problem with memory mapping and RAM size or
> > with OMAP HS mode?
>
> RAM size should be ok... how do I check for OMAP HS problems?

For problems with smc or any other it is needed to look into kernel log :-(

--
Pali Roh?r
pali.rohar at gmail.com