riaancillie

To make plymouth work on khadas edge, the boot command line arguments must be modified to include
splash quiet plymouth.ignore-serial-consoles vt.handoff=7

(note if you need to debug, also add plymouth.debug to the above and then after boot open /var/log/plymouth-debug.log)
(verify that the above kernel command line arguments are added by cat /proc/cmdline )
(Most likely the theme used was not found or not applied fix by running
sudo update-alternatives --install /usr/share/plymouth/themes/default.plymouth default.plymouth /usr/share/plymouth/themes/spinner/spinner.plymouth 100
sudo update-initramfs -u
reboot
)

riaancillie

Khadas/Rockchip stores the logo to be displayed after power on in a partition called "resource" which is located at 0x0000 a000
The file system in proprierty but can be generated using a a tool provided by rockchip. There appears to be a limit on the bitmap 
that can be displayed. 1000x1000px works fine, but 2048x1536 causes a interleaved effect when starting up although correcting 
itself after a few seconds.
Note that the partition is only 16mb in size.

To create a new logo.img file, use resource_tool, either from rkbin in fenix/build/rkbin____/tools folder or by cloning repo 
https://github.com/linux-rockchip/u-boot-rockchip/blob/u-boot-rk3288/tools/resource_tool/resource_tool.c which also provides
source code.

riaancillie

/*
 * Copyright (c) 2018 Wesion Co., Ltd.
 *
 * SPDX-License-Identifier:     GPL-2.0+
 */

/* RC Notes: DTS for u-boot to display logo on eDP
The DTS used for linux will not switch on the panel properly due to rockchip_display.c implement the tree differently
It was necessary to change the way the ports of the eDP node is mapped to the panel
Also, even when the panel is mapped properly, the backlight did not turn on because the rockchip display

riaancillie

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 4.4.167 (khadas@bec9b798575d) (gcc version 7.3.1 20180425 [linaro-7.3-2018.05 revision d29120a424ecfbc167ef90065c0eeb7f91977701] (Linaro GCC 7.3-2018.05) ) #1 SMP Tue Aug 20 20:54:03 UTC 2019
[    0.000000] Boot CPU: AArch64 Processor [410fd034]
[    0.000000] Machine model: Khadas Edge-V
[    0.000000] On node 0 totalpages: 516096
[    0.000000]   DMA zone: 8184 pages used for memmap
[    0.000000]   DMA zone: 0 pages reserved

riaancillie

[    0.000000] Booting Linux on physical CPU 0x0
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Initializing cgroup subsys cpuacct
[    0.000000] Linux version 4.4.167 (khadas@bec9b798575d) (gcc version 7.3.1 20180425 [linaro-7.3-2018.05 revision d29120a424ecfbc167ef90065c0eeb7f91977701] (Linaro GCC 7.3-2018.05) ) #1 SMP Tue Aug 20 20:54:03 UTC 2019
[    0.000000] Boot CPU: AArch64 Processor [410fd034]
[    0.000000] Machine model: Khadas Edge-V
[    0.000000] On node 0 totalpages: 516096
[    0.000000]   DMA zone: 8184 pages used for memmap
[    0.000000]   DMA zone: 0 pages reserved

riaancillie

/dts-v1/;

#include "rk3399-khadas-edge.dtsi"

/ {
	model = "Khadas Edge-V";
	compatible = "khadas,edgev", "rockchip,rk3399";

        edp_panel: edp-panel {
                compatible ="lg,lp097qx1-spa1", "simple-panel";