On 2/8/22 16:23, Geert Uytterhoeven wrote: [snip] >>> - The logo (I have a custom monochrome logo enabled) is no longer shown. >> >> I was able to display your tux monochrome with ./fbtest -f /dev/fb1 test004 > > I meant the kernel's logo (FB_LOGO_*),. Obviously you need to enable > a smaller one, as the default 80x80 logo is too large, and thus can't > be drawn on your 128x64 or my 128x32 display. > That makes sense. >>> - The screen is empty, with a (very very slow) flashing cursor in the >>> middle of the screen, with a bogus long line next to it, which I can >>> see being redrawn. >>> - Writing text (e.g. hello) to /dev/tty0, I first see the text, >>> followed by an enlargement of some of the characters. >> >> So far I was mostly testing using your fbtest repo tests and all of them >> (modulo test009 that says "Screen size too small for this test"). >> >> But I've tried now using as a VT and I see the same visual artifacts. I >> wonder what's the difference between fbcon and the way your tests use >> the fbdev API. > > Fbcon does small writes to the shadow frame buffer, while fbtest > writes to the mmap()ed /dev/fbX, causing a full page to be updated. > I see. Thanks for the information. Best regards, -- Javier Martinez Canillas Linux Engineering Red Hat