Most recent kernel where this bug did not occur: 2.6.16.20 Distribution: gentoo -- vanilla sources Hardware Environment: dual opteron, mga g550, lcd connected via dvi Software Environment: framebuffer console Problem Description: after upgrading to 2.6.17 on an opteron smp machine (x86_64 kernel) with a mga g550 vga several dots around letters on a framebuffer console are flickering. matroxfb is compiled as a module. this also happens to an X server using mga and fbhw submodule. Steps to reproduce:
Created attachment 8345 [details] Do not program XDVICLKCTRL
Can you try http://bugzilla.kernel.org/attachment.cgi?id=8345&action=view to make sure that problem is where I think it is ? You may have to power cycle your computer after applying patch to make sure MGA is reinitialized from scratch.
hi petr! your patch fixes this issue! thank you very much!!!! markus
I added that line of code in my patch. Let me look into it a bit. Perhaps the best thing, since this report is on x86-64 and the problem I was addressing with my patch was specific to ppc/ppc64, would be to use that code only on x86-64 (via ifdef). I'll post that patch here in a bit.
Created attachment 8354 [details] program XDVICLKCTRL only on powerpc this patch is a compromise, which should work on both powerpc and non-powerpc systems. programming the XDVICLKCTRL register, which fixed jitter on powerpc systems and apparently introduced jitter on non-powerpc systems, has been limited to just powerpc systems
hi, it seems that this patch did not make it into the sources till 2.6.17.5. any chance it will be included in future versions? thanx, markus
Gentlemen, have you all agreed on fix? Can someone send it to Andrew so 2.6.18 won't flicker?
I was under impression that this XDVICLKCTRL access is already under '#ifdef CONFIG_PPC' in 2.6.18-rc4. Apparently it is not, I have no idea why, I'll resend patch.
commit b8cf368944807e29b16b24588a2a35c829bc9d9a closing