Selfcompiled Linux Kernel does not boot

#1

Hello Everyone,
I am trying to build a Linux kernel with 115200 baudrate and boot it via U-Boot from SD card. But I get no output whatever I try.
That is the output I get from u-boot:
SoC: Rockchip rk3399
Reset cause: POR
Model: Radxa ROCK Pi 4C
DRAM: 3.9 GiB
PMIC: RK808
Core: 273 devices, 26 uclasses, devicetree: separate
MMC: mmc@fe310000: 2, mmc@fe320000: 1, mmc@fe330000: 0
Loading Environment from MMC… *** Warning - bad CRC, using default environment

In: serial
Out: serial
Err: serial
Model: Radxa ROCK Pi 4C
Net: eth0: ethernet@fe300000
Hit any key to stop autoboot: 0
switch to partitions #0, OK
mmc1 is current device
Scanning mmc 1:3…
Found /extlinux/extlinux.conf
Retrieving file: /extlinux/extlinux.conf
1: rockpi4-plus-openadk
Retrieving file: /kernel
append: console=ttyS2,115200n8 rw rootwait
Retrieving file: /rk3399-rock-pi-4c.dtb

Flattened Device Tree blob at 01f00000

Booting using the fdt blob at 0x1f00000
ERROR: reserving fdt memory region failed (addr=0 size=0 flags=0)
Loading Device Tree to 00000000f1ef8000, end 00000000f1f129b0 … OK

Starting kernel …

After that nothing shows up. I tried following Linux Kernels:
Linux Upstream 6.12
Linux Upstream 5.15.81
Radxa Kernel from https://github.com/radxa/kernel.git
Both stable-4.4-rockpi4 and latest 5.10.110

My extlinux.conf is:
label rockpi4-plus-openadk
kernel /kernel
devicetree /rk3399-rock-pi-4c.dtb
append console=ttyS2,115200n8 rw rootwait

The exact device is Rock PI4 Plus V1.73.
I always patched the kernel DTS file to use 115200 instead of 1500000.

Does anybody have a tipp for me?
best regards
Waldemar

#2

This will work:

#3

Thanks for the link. I got a little further with my self compiled kernel.
The issue I had was a missing and valid bl31.elf while compiling u-boot.
Now the kernel boots up, but do not find the SD card.
The patch adding the board support for Rockpi4 C plus adds a DTS file which includes enabling the SD card.
All looks good, the driver is loaded while startup, it seems to match the OF node,
but only the first mmc device is recognized. The second on @fe320000 is not.
[ 3.279303] dwmmc_rockchip fe310000.mmc: IDMAC supports 32-bit address mode.
[ 3.288844] dwmmc_rockchip fe310000.mmc: Using internal DMA controller.
[ 3.296257] dwmmc_rockchip fe310000.mmc: Version ID is 270a
[ 3.302514] dwmmc_rockchip fe310000.mmc: DW MMC controller at irq 32,32 bit host data width,256 deep fifo

And that is all. Anyone an idea why the SD card is not recognized?
best regards
Waldemar

#4

in first post, it seems you tried to use U-Boot and kernel/dtb for ROCK Pi 4C. but your board (V1.73) should be Rock Pi 4A+ or 4B+.

in second post, you are trying to use files for ROCK 4C+.

please use files for ROCK Pi 4B or 4B+.

#5

Hi all,
you are completely right, switching to rockpi 4b does the trick.
Now it boots up! Thanks a lot for the help.
best regards
Waldemar