Odd Graphical Glitches with AMD HD 6250

[Mirage256]

Aloha! I've been able to install Haiku on an old Laptop of mine, a Toshiba NB550D. However, there are a bunch of very odd graphical glitches that render the interface almost unusable. There's a snow effect across the entire screen, like an old CRT that isn't tuned to a channel, and all of the colors are very saturated and have an odd sort of color fringing around them. I will attach a screenshot to this bug to show what I mean.

The Toshiba NB550D uses an AMD Radeon HD 6250 as its graphics card.The graphics card appears to be recognized by Haiku; the proper screen resolution is detected in the screen settings program, and when I look in the source code in haiku/src/add-ons/kernel/drivers/graphics/radeon_hd/driver.cpp, I can see that the Radeon HD 6250 appears to be supported, as there is a dedicated entry for it in the driver. The system has not been customized in any way; I saw these effects in the installation environment, and they're present from the very first boot and log in.

Please advise if there's anything I can provide that would assist in debugging this issue, such as log files. I have a fair bit of experience with Linux and several of the BSDs, but Haiku is a new platform for me, so I will need guidance in figuring out what to provide.

Thank you for your time!

[Mirage256]

Example of Graphical Errors

[Mirage256]

Photo of Graphical Issue

[Mirage256]

Well, I found something interesting - the screenshot doesn't capture the issues, they only appear on the physical screen itself. I took a photo with my phone to demonstrate. I'm nearly certain that these graphical artifacts are a software problem, as they don't show up under any other operating system, such as Windows 7 or any Linux distribution I've tried so far.

[madmax]

Well, I found something interesting - the screenshot doesn't capture the issues,

That's expected when the problem is in the graphics driver or hardware.

Please advise if there's anything I can provide

There's probably something interesting from the driver or the panel detection in the system log: /var/log/syslog.

Something you can try, apart from other color depth settings, is to boot in VESA mode, bypassing the specific driver. Select "Use fail-safe graphics driver" in the ​bootloader. You may also have to manually select the screen resolution, and even the exact one may not be available depending on BIOS, but at least it may get you a usable desktop. Include also a syslog booting in this mode.

[Mirage256]

I tried to change the color depth settings, which did affect the color of the artifacts and the amount of "snow", but didn't remove them. I am going to attach a copy of the syslog file right now as is, then reboot into the VESA only mode and report what happens (and attach copy of the system log after that as well)

[Mirage256]

/var/log/syslog before using VESA safe mode

[Mirage256]

Okay, I was able to boot into safe mode with the VESA compatibility driver. It does indeed fix the graphical glitches - the colors now lookg normal, and there is no artifacting. However, it doesn't support the native resolution of the panel, so everything looks distorted horizontally. Additionally, it didn't load the wifi drivers in safe mode, so I made a copy of the system log before rebooting and will now upload that copy.

[Mirage256]

System log after rebooting into VESA mode

[thebuck]

Replying to madmax:

Well, I found something interesting - the screenshot doesn't capture the issues,

That's expected when the problem is in the graphics driver or hardware.

The radeon_hd driver is definitely capable of screenshottable noise as well, as seen in #17664.

[madmax]

Replying to Mirage256:

Additionally, it didn't load the wifi drivers in safe mode

Did you also mark "Safe mode"? "Use fail-safe graphics driver", a few items below, should be enough and affect only the graphics driver.

However, it doesn't support the native resolution of the panel

There's an option that might help, but citing the source:

On some video cards, the VESA driver is able to inject custom video resolutions in the BIOS.
This does not modify the BIOS in the hardware, the changes are erased on reboot. However,
this is outside of VESA specifications and sometimes results in a black screen. As a result,
this feature is disabled by default.

And if it doesn't give you a desktop, as far as I know you'd have to boot some other way (like with the default faulty radeon_hd driver) to disable it.

If you are willing to experiment anyway, create (or edit if it already exists) a simple text file in /boot/home/config/settings/kernel/drivers/vesa, add the following line:

bios_patching true

and reboot with the fail-safe graphics driver option. If it does help, you can also force the VESA mode so that you don't have to set it on every boot until the problem is fixed by uncommenting the fail_safe_video_mode true line in /boot/home/config/settings/kernel/drivers/vesa.

[Mirage256]

Did you also mark "Safe mode"? "Use fail-safe graphics driver", a few items below, should be enough and affect only the graphics driver.

I did, my mistake! Enabling just the fail-safe graphics driver option causes the WiFi to work perfectly, which makes the safe mode much more usuable.

There's an option that might help, but citing the source: (...)

I tried enabling this bios patching feature. On the bright side, it didn't cause a black screen or anything - though on the downside, it also didn't enable any new modes or change anything about how the vesa driver functions. I tried looking in the syslog after, and I found these lines:

KERN: vesa: unknown BIOS type, custom video modes will not be available

KERN: vesa: vesa_init() completed successfully!

This could be from earlier, so I'm not sure if it's significant, but it seems like the patching feature might not be supported on this card.

Thank you very much for your help by the way, I greatly appreciate it!