Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

[Cao Minh Hiep]

Hi All.

We are testing Linux upstream version-4.1-rc2 on Lager.
We found a Error message of DU(Display Unit) at boot logs:
The Warning messages is showed as below:
"rcar-du feb00000.display: encoder initialization failed, skipping"
Then we tried to show a .bmp image on RGB Display via RGB port. But it 
didn't work.

Testing method:
1. Connect RGB Display to RGB port on Lager.
2. Show a BMP image on Display by this command:
# bmap /dev/fb0 ./image.bmp

We'd like to report this problem first.
There are no error message at version v4.0 stable.
And showed the image on RGB Display normally at version v4.0 stable.
We are looking for the error patch that added between v4.0 and v4.1-rc2.

Best Regards,
Jinso/Cao Minh Hiep.

Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

[Laurent Pinchart]

Hello,

On Wednesday 13 May 2015 15:43:36 Cao Minh Hiep wrote:
> Hi All.
> 
> We are testing Linux upstream version-4.1-rc2 on Lager.
> We found a Error message of DU(Display Unit) at boot logs:
> The Warning messages is showed as below:
> "rcar-du feb00000.display: encoder initialization failed, skipping"
> Then we tried to show a .bmp image on RGB Display via RGB port. But it
> didn't work.
> 
> Testing method:
> 1. Connect RGB Display to RGB port on Lager.
> 2. Show a BMP image on Display by this command:
> # bmap /dev/fb0 ./image.bmp
> 
> We'd like to report this problem first.
> There are no error message at version v4.0 stable.
> And showed the image on RGB Display normally at version v4.0 stable.
> We are looking for the error patch that added between v4.0 and v4.1-rc2.

I've tried v4.1-rc2 and haven't experienced that problem. It might be related 
to kernel configuration, could you please share your .config file ?

-- 
Regards,

Laurent Pinchart

Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

[Cao Minh Hiep]

Hi Laurent-san,

I'd like to report some more informations

On 2015年05月14日 06:56, Laurent Pinchart wrote:
> Hello,
>
> On Wednesday 13 May 2015 15:43:36 Cao Minh Hiep wrote:
>> Hi All.
>>
>> We are testing Linux upstream version-4.1-rc2 on Lager.
>> We found a Error message of DU(Display Unit) at boot logs:
>> The Warning messages is showed as below:
>> "rcar-du feb00000.display: encoder initialization failed, skipping"
>> Then we tried to show a .bmp image on RGB Display via RGB port. But it
>> didn't work.
>>
>> Testing method:
>> 1. Connect RGB Display to RGB port on Lager.
>> 2. Show a BMP image on Display by this command:
>> # bmap /dev/fb0 ./image.bmp
>>
>> We'd like to report this problem first.
>> There are no error message at version v4.0 stable.
>> And showed the image on RGB Display normally at version v4.0 stable.
>> We are looking for the error patch that added between v4.0 and v4.1-rc2.
> I've tried v4.1-rc2 and haven't experienced that problem. It might be related
> to kernel configuration, could you please share your .config file ?
>

We found that, if revert these patches then rebuild kernel, the error 
logs "encoder initialization failed..." will be disappeared:
26c00ab ARM: shmobile: lager: Add DU external pixel clocks to DT
fd25cdd ARM: shmobile: lager: Add DU HDMI output support
These patch added between v4.0 and v4.1-rc2.
But with this test, a bmp image still could not show on RGB Display.


Thank you.
Jinso/Hiep.

Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

[Cao Minh Hiep]

Hi Laurent-san,

On 2015年05月14日 12:18, Cao Minh Hiep wrote:
> Hi Laurent-san,
>
> I'd like to report some more informations
>
> On 2015年05月14日 06:56, Laurent Pinchart wrote:
>> Hello,
>>
>> On Wednesday 13 May 2015 15:43:36 Cao Minh Hiep wrote:
>>> Hi All.
>>>
>>> We are testing Linux upstream version-4.1-rc2 on Lager.
>>> We found a Error message of DU(Display Unit) at boot logs:
>>> The Warning messages is showed as below:
>>> "rcar-du feb00000.display: encoder initialization failed, skipping"
>>> Then we tried to show a .bmp image on RGB Display via RGB port. But it
>>> didn't work.
>>>
>>> Testing method:
>>> 1. Connect RGB Display to RGB port on Lager.
>>> 2. Show a BMP image on Display by this command:
>>> # bmap /dev/fb0 ./image.bmp
>>>
>>> We'd like to report this problem first.
>>> There are no error message at version v4.0 stable.
>>> And showed the image on RGB Display normally at version v4.0 stable.
>>> We are looking for the error patch that added between v4.0 and 
>>> v4.1-rc2.
>> I've tried v4.1-rc2 and haven't experienced that problem. It might be 
>> related
>> to kernel configuration, could you please share your .config file ?
>>
>
> We found that, if revert these patches then rebuild kernel, the error 
> logs "encoder initialization failed..." will be disappeared:
> 26c00ab ARM: shmobile: lager: Add DU external pixel clocks to DT
> fd25cdd ARM: shmobile: lager: Add DU HDMI output support
> These patch added between v4.0 and v4.1-rc2.
> But with this test, a bmp image still could not show on RGB Display.
>
We used "git log" as below to get the change patches from v4.0 to v4.1-rc2:

#git log --oneline --no-merges v4.0..v4.1-rc1 drivers/gpu/drm/rcar-du/

Firstly, We reverted all of them and re-build kernel. This case we could 
show a bmp image on RGB Display.
Next, we add each patch from bottom to up then tested.
We found that when added the commit "8b37c32 drm: rcar-du: Don't set 
connector->encoder at init time".
we could not show image on Display any more.

Jinso/Hiep.

==================

jinso02@jinso02:~/WORK/linux$ git log --oneline --no-merges 
v4.0..v4.1-rc1 drivers/gpu/drm/rcar-du/
4af642d drm/rcar-du: use for_each_endpoint_of_node macro
6dbe686 drm: rcar-du: Enable the atomic updates API
3515a9a drm: rcar-du: Don't initialize event->pipe field
de115fac drm: rcar-du: Fix framebuffer reference leak through plane state
5ee5a81 drm: rcar-du: Fix race condition in hardware plane allocator
48596d5 drm: rcar-du: Move group locking inside rcar_du_crtc_update_planes()
52055ba drm: rcar-du: Move plane commit code from CRTC start to CRTC resume
5bfcbce drm: rcar-du: Move plane format to plane state
53dff60 drm: rcar-du: Remove unneeded rcar_du_crtc plane field
4709419 drm: rcar-du: Replace plane crtc and enabled fields by plane state
f398f34 drm: rcar-du: Rework plane setup code
4407cc0 drm: rcar-du: Switch plane set_property to atomic helpers
d574664 drm: rcar-du: Switch page flip to atomic helpers
8d3f9b2 drm: rcar-du: Implement asynchronous commit support
ede7714 drm: rcar-du: Replace encoder mode_fixup with atomic_check
f348323 drm: rcar-du: Switch connector DPMS to atomic helpers
cf1cc6f drm: rcar-du: Switch mode config to atomic helpers
336d04a drm: rcar-du: Switch plane update to atomic helpers
beff155 drm: rcar-du: Rework CRTC enable/disable for atomic updates
58706b8 drm: rcar-du: Rework HDMI encoder enable/disable for atomic updates
f6638b6 drm: rcar-du: Rework encoder enable/disable for atomic updates
44ef7ed drm: rcar-du: Replace LVDS encoder DPMS by enable/disable
287bdf0 drm: rcar-du: Remove private copy of plane size and position
3e8da87 drm: rcar-du: Wire up atomic state object scaffolding
845f463 drm: rcar-du: Handle primary plane config through atomic plane ops
920888a drm: rcar-du: Implement planes atomic operations
3053460 drm: rcar-du: Fix hardware plane allocation
917de18 drm: rcar-du: Implement universal plane support
a64b9c7 drm: rcar-du: Define macros for the max number of groups, CRTCs 
and LVDS
931b733 drm: rcar-du: Disable fbdev emulation when no connector is present
0cd90a5 drm: rcar-du: Turn vblank on/off when enabling/disabling CRTC
36693f3 drm: rcar-du: Wait for page flip completion when turning the 
CRTC off
17f6b8a drm: rcar-du: Reorder CRTC functions

Bug here:
8b37c32 drm: rcar-du: Don't set connector->encoder at init time        
                                 NG

df78222 drm: rcar-du: Remove drm_fbdev_cma_restore_mode() call at init 
time                OK
0e211da drm: rcar-du: Don't disable unused functions at init time     
                                OK
f033c0b of: Decrement refcount of previous endpoint in 
of_graph_get_next_endpoint        OK

Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

[Laurent Pinchart]

Hello Hiep-san,

Sorry for the late reply.

On Thursday 14 May 2015 12:18:21 Cao Minh Hiep wrote:
> Hi Laurent-san,
> 
> I'd like to report some more informations
> 
> On 2015年05月14日 06:56, Laurent Pinchart wrote:
> > On Wednesday 13 May 2015 15:43:36 Cao Minh Hiep wrote:
> >> Hi All.
> >> 
> >> We are testing Linux upstream version-4.1-rc2 on Lager.
> >> We found a Error message of DU(Display Unit) at boot logs:
> >> The Warning messages is showed as below:
> >> "rcar-du feb00000.display: encoder initialization failed, skipping"
> >> Then we tried to show a .bmp image on RGB Display via RGB port. But it
> >> didn't work.
> >> 
> >> Testing method:
> >> 1. Connect RGB Display to RGB port on Lager.
> >> 2. Show a BMP image on Display by this command:
> >> # bmap /dev/fb0 ./image.bmp
> >> 
> >> We'd like to report this problem first.
> >> There are no error message at version v4.0 stable.
> >> And showed the image on RGB Display normally at version v4.0 stable.
> >> We are looking for the error patch that added between v4.0 and v4.1-rc2.
> > 
> > I've tried v4.1-rc2 and haven't experienced that problem. It might be
> > related to kernel configuration, could you please share your .config file
> > ?
>
> We found that, if revert these patches then rebuild kernel, the error
> logs "encoder initialization failed..." will be disappeared:
> 26c00ab ARM: shmobile: lager: Add DU external pixel clocks to DT
> fd25cdd ARM: shmobile: lager: Add DU HDMI output support
> These patch added between v4.0 and v4.1-rc2.
> But with this test, a bmp image still could not show on RGB Display.

The error message isn't fatal. It's caused by HDMI support being disabled for 
the rcar-du driver, so the driver warns that the HDMI encoder can't be 
initialized.

I'll submit a patch that adds the encoder name to the error message to ease 
debugging, but the message itself is normal. The driver should initialize all 
the other encoders properly.

I've retested this on a stock v4.1-rc2 kernel with the kernel configuration 
file you've provided. I can reproduce the error message, and then noticed a 
potential kernel crash caused by a bug in the rcar-du driver. I have submitted 
a patch to fix it (and have CC'ed you).

With the fix applied I can use the DU normally with the modetest application. 
I've also tested the fbdev compat layer, and can confirm that you won't get an 
output on the screen if you don't configure the display first. This can be 
done through the KMS API or the FBDEV API (FBIOPUT_VSCREENINFO).

-- 
Regards,

Laurent Pinchart

Re: [Bug Report] DU: Error messages at boot log and can't show image on RGB Display.

[Cao Minh Hiep]

Hi Laurent-san
Thanks for your feedback

>>>> We'd like to report this problem first.
>>>> There are no error message at version v4.0 stable.
>>>> And showed the image on RGB Display normally at version v4.0 stable.
>>>> We are looking for the error patch that added between v4.0 and v4.1-rc2.
>>> I've tried v4.1-rc2 and haven't experienced that problem. It might be
>>> related to kernel configuration, could you please share your .config file
>>> ?
>> We found that, if revert these patches then rebuild kernel, the error
>> logs "encoder initialization failed..." will be disappeared:
>> 26c00ab ARM: shmobile: lager: Add DU external pixel clocks to DT
>> fd25cdd ARM: shmobile: lager: Add DU HDMI output support
>> These patch added between v4.0 and v4.1-rc2.
>> But with this test, a bmp image still could not show on RGB Display.
> The error message isn't fatal. It's caused by HDMI support being disabled for
> the rcar-du driver, so the driver warns that the HDMI encoder can't be
> initialized.
>
> I'll submit a patch that adds the encoder name to the error message to ease
> debugging, but the message itself is normal. The driver should initialize all
> the other encoders properly.
>
> I've retested this on a stock v4.1-rc2 kernel with the kernel configuration
> file you've provided. I can reproduce the error message, and then noticed a
> potential kernel crash caused by a bug in the rcar-du driver. I have submitted
> a patch to fix it (and have CC'ed you).
>
> With the fix applied I can use the DU normally with the modetest application.
> I've also tested the fbdev compat layer, and can confirm that you won't get an
> output on the screen if you don't configure the display first. This can be
> done through the KMS API or the FBDEV API (FBIOPUT_VSCREENINFO).
>
Thanks for you patches and support.
I have tried to add your patches to v4.1-rc2 or rc5 for testing,
but I couldn't add the patch of [PATCH 1/3]:

"[PATCH 1/3] drm: rcar-du: Fix crash with groups that have less than 9 planes"

Could you please tell me which version can I add these patches?

Best regards,
Hiep.