[Letux-kernel] TILER patch problem on omap3 mmap(/dev/fb0) -- [PATCH] fbpng: make it work with 32 bpp fb

[Andreas Kemnade]

On Tue, 23 Jan 2018 10:38:13 +0100
"H. Nikolaus Schaller" <hns at goldelico.com> wrote:
[...]
> 
> I found a simpler "proof of bug" using the latest kernel from our downloads:
> 
I was wondering why you did not do that in the first place. I was just
doing research about how to boot test setups, so I did it the other way.

[...]
> root at letux:~# ./fbpng /usr/share/pixmaps/debian-logo.png
> /usr/share/pixmaps/debian-logo.png: 48x48 @ 24bp[  146.310180] Unhandled fault: imprecise external abort (0x1c06) at 0xb6c8d020
> [  146.321441] pgd = e15e8173
> [  146.324279] [b6c8d020] *pgd=958d2831, *pte=9e900353, *ppte=9e900873
> p
> [  146.331054] Unhandled fault: imprecise external abort (0x1c06) at 0xdc91bfe8
> [  146.338592] pgd = 4405b38c
> [  146.341430] [dc91bfe8] *pgd=9c80041e(bad)
> Bus error
> root at letux:~# 
> 
> On omap5 the same procedure succeeds.
> 
> Now I can help to find out what the reason could be...
> 
well, suspicious should be everything not guarded by if
(... OMAP_BO_TILED ...).
But for the other things, I do not understand so well whether that
can have influences.

Regards.
Andreas