Hello Geert,
Thanks a lot for testing!
On 2/8/22 15:19, Geert Uytterhoeven wrote:
Hi Javier,
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
- 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.
- "time ls" on the serial console (no files in the current directory, so nothing to print) increases from 0.86s to 1.92s, so the system is more loaded. As ssd1307fb relied on deferred I/O too, the slowdown might be (partly) due to redrawing of the visual artefacts mentioned above.
I was trying to first have the driver and then figure out how to optimize it. For v3 I'm using regmap to access instead of the I2C layer directly.
I noticed that this is even slower but it makes the driver more clean and allows to support both I2C and SPI (untested but will include it as a WIP).
So while the displays seems to be initialized correctly, it looks like there are some serious bugs in the conversion from xrgb8888 to monochrome.
Yes, that's possible. I haven't tried to use it as a console before because the display resolution is just too small. But will include now in my tests.
Gr{oetje,eeting}s,
Best regards,