The interesting part: Detailed Timing Descriptor I used a web based tool to decode the EDID. It looks like nwl-dsi was added to vendor (boundary) U-Boot in March: video: imx: nwl-drv, nwl-dsi: initial addition Printf("# Failed to enable host: %d", ret) +++ -64,10 +64,24 pinctrl_backlight: backlightgrp ,ĭsi_host_init(nwl_dsi, &device, &timings, 4 /* lanes */, NU a/arch/arm/dts/imx8mq-nitrogen8m_som.dts My current patch for the boundary U-Boot fork (the define for GP_SN65DSI86_ENABLE doesn’t do anything): $ git -no-pager diffĭiff -git a/arch/arm/dts/imx8mq-nitrogen8m_som.dts b/arch/arm/dts/imx8mq-nitrogen8m_som.dts I can use the U-Boot gpio command to enable/disable the backlight even though it will always report the pin as off. I also discovered that reading the GPIO state doesn’t seem to work ( dm_gpio_get_value just after dm_gpio_set_value returns 0). The U-Boot documentation in the doc directory in the source tree was helpful in understanding things better. # Set COLOR_BAR_EN, this doesn't show anything yet as output requires following power up sequence. # (Reversed) magic string from data sheet checks out # Device tree shows address 0x2c, let's confirm: In case someone else wants to poke around on the U-Boot command line: => i2c busīus 0: 1: 2: 3: Device tree shows attached to i.e. They should all be in the Linux device tree, but I hit my limit for looking at weird numbers for today. For this, I need to figure out the right parameters. I☬ poking worked fine, but I need to properly follow the power up sequence to make it show anything. I think I need to look at the device tree inside U-Boot instead of the code. I could change the pin type to output by modifying the code and recompiling U-Boot, but actually changing the value using the gpio command didn’t work. I haven’t been able to change its value so far. I poked around a bit using the helpful i2c U-Boot command and also tried to use the gpio command for BACKLIGHT_EN ( GPIO1_IO10 per schematic). Thanks for the pointers, this is helpful! I’m not sure on the preferred way to handle testing (typing commands on the internal keyboard without copy/paste would be tedious and error prone as well), but for general boot I’m considering changing U-Boot to read a script file from SD/MMC, writing U-Boot to MMC and changing the boot order on the SOM to set boot from MMC as default as hinted at in Advanced Chapter of the handbook. Saving the U-Boot environment doesn’t seem to work (I saw comments around MMC/SD for env storage and crashes when trying to save on SD), so I had to copy commands during testing and then recompile U-Boot and add it to the SD to hardcode working commands. Restarting the SOM is possible with a button on the back. The serial connector is on the bottom, but the only way to turn on the SOM I found is by using the keyboard (Circle, 1) on the other side. I was working on getting ArchLinux ARM running (Spoiler: Unless you have a kernel with I suspect at least the PCIe clock patch, USB and Wifi won’t work the internal panel doesn’t work on ALARM 12.3 either.) and the U-Boot experience isn’t great. Is it feasible to get output on the internal screen? What would be required? Is there something I've missed? Trawling through the forums has not found any information that I can find.A recent commit seems to indicate that HDMI output from U-Boot is now supported. So just in case it was my build, I downloaded the latest Buster server build (Linux 5.4.20-sunxi) and edited armbvianEnv.txt to enable the logo. Now, after the build, even with logo=enabled in armbianEnv.txt (this is also probably been superseded during the last year) I have no splash screen during kernel boot. In the past I had patched general-armbian-boot-logo-on-screen-center.patch and general-armbian-boot-logo-on-screen-center copy.patch to show the splash screen I required however now these patches are this patch is no longer even referenced during the build process. It been a while since I have made custom images for the OrangePi PC Plus so things have changed a bit in the intervening period.įirst I made the development environment change to Ubuntu Focal, then changes to a couple of patch files to bring them into line with the new u-boot and kernel versions however I have simply lost the ability to display an Armbian splash screen during boot.
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