Hi Javier,
On Tue, Feb 8, 2022 at 4:10 PM Javier Martinez Canillas javierm@redhat.com wrote:
On 2/8/22 15:19, Geert Uytterhoeven wrote:
On Fri, Feb 4, 2022 at 2:43 PM Javier Martinez Canillas javierm@redhat.com 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@linux-m68k.org
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