Hi Javier,
On Tue, Feb 8, 2022 at 4:10 PM Javier Martinez Canillas
<javierm@xxxxxxxxxx> wrote:
> On 2/8/22 15:19, Geert Uytterhoeven wrote:
> > On Fri, Feb 4, 2022 at 2:43 PM Javier Martinez Canillas
> > <javierm@xxxxxxxxxx> wrote:
> >> This patch series adds a DRM driver for the Solomon OLED SSD1305, SSD1306,
> >> SSD1307 and SSD1309 displays. It is a port of the ssd1307fb fbdev driver.
> >
> > I gave it a try on an Adafruit FeatherWing 128x32 OLED, connected to an
> > OrangeCrab ECP5 FPGA board running a 64 MHz VexRiscv RISC-V softcore.
> >
> > Findings:
> > - Kernel size increased by 349 KiB,
> > - The "Memory:" line reports 412 KiB less memory,
> > - On top of that, "free" shows ca. 92 KiB more memory in use after
> > bootup.
> > - 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.
> > - 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.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
