Re: [PATCHv6 0/4] omapdrm: DSI command mode panel support

From: Tony Lindgren
Date: Thu May 30 2019 - 03:06:09 EST


* Tony Lindgren <tony@xxxxxxxxxxx> [190530 05:47]:
> * Tony Lindgren <tony@xxxxxxxxxxx> [190529 08:11]:
> > * Tomi Valkeinen <tomi.valkeinen@xxxxxx> [190529 07:06]:
> > > On 28/05/2019 13:18, Tony Lindgren wrote:
> > >
> > > > > My board is x15 rev A3, attached to AM5 EVM. I've also attached my kernel
> > > > > config.
> > > >
> > > > Strange that this is not affecting other x15? I think timer12 would
> > > > be blocked on HS devices though?
> > >
> > > Seems that the kernel config affects. omap2plus_defconfig boots ok.
> >
> > OK, this line in your oops:
> >
> > Unable to handle kernel paging request at virtual address 5a5a5a5a
> >
> > Probably means we hit some slab poison with DEBUG_SLAB set.
> > Looks like your config boots fine with DEBUG_SLAB disabled
> > for me.
> >
> > As this only happens for timer12, I wonder if we're again
> > hitting some uncompress issue with corrupted dtb. Changing
> > u-boot ftdaddr higher up might possibly make it go away.
> > Or else there's a bug elsewhere :)
>
> Oh but CM_WKUPAON_TIMER12_CLKCTRL has no CLKSEL option unlike
> CM_WKUPAON_TIMER1_CLKCTRL. Below is one part of the fix, but
> it seems like we're missing handling somewhere as trying to
> get a non-existing clock should just produce -ENODEV type error.
>
> And the clksel should be just handled with assigned-clocks
> in general, but I think we still need it there until we
> have drivers/clocksource/ timer drivers updated to boot
> using early_platform_device.

OK found it, we have the clkctrl clock potentially return
uninitialized data. I posted two fixes for the issue:

[PATCH] clk: ti: clkctrl: Fix returning uninitialized data
[PATCH] ARM: dts: Drop bogus CLKSEL for timer12 on dra7

Regards,

Tony