[Letux-kernel] LX20 prototype is booting

[H. Nikolaus Schaller]

Hi,

> Am 27.04.2025 um 13:15 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
> 
> Hi all,
> 
> Here is some more progress using the old ll_printk() method we had develped to debug
> the x1600 boot process and bring up a v6.6 kernel on the lx16.
> 
> This means we can now load kernel and FDT blobs. And the kernel entry point is jumped to.
> Then, progress is stuck - likely while initializing the cpu (where I just have a very rough
> DTS record for).
> 
> Current kernel code is here:
> 
> https://git.goldelico.com/?p=letux-kernel.git;a=shortlog;h=refs/heads/work-lx20
> 
> This reveals the location and meaning of the messages we see.

Paul has made me aware of an x2000.dtsi on github. It will save us a lot of time 
to develop the device tree files :) A great THANKS!!!

	https://github.com/Ingenic-community/linux

Using this makes the boot process go a little further after cpu_probe() into setup_arch().

So we are still digging in the right direction.

WHat is likely missing is some driver code/patches.

I think I will now try to compile their full 6.1.y kernel, but then I have to backport
some LX20 specific additions (at least lx20 device tree and defconfig and perhaps tweaking
Kconfigs).

BR,
Nikolaus


> Starting FDT kernel 8093817c(-2, 87ffc000, 00000000, 0);...
> 
> start_kernel: start
> start_kernel: after set_task_stack_end_magic
> start_kernel: after smp_setup_processor_id
> start_kernel: after init_vmlinux_build_id
> start_kernel: after cgroup_init_early
> start_kernel: after local_irq_disable
> start_kernel: after boot_cpu_init
> start_kernel: after page_address_init
> start_kernel: after pr_notice: linux_banner=Linux version 6.15.0-rc3-letux-lx20+ (hns at iMac.local) (mipsel-linux-gnu-gcc (GCC) 6.3.0, GNU ld (GNU Binutils) 2.27) #2359 PREEMPT Sun Apr 27 12:20:15 CEST 2025
> start_kernel: after early_security_init
> setup_arch: start
> cpu_probe: start
> cpu_probe: after set_elf_platform
> cpu_probe: after read_c0_prid id = 00132000
> cpu_probe: after switch: cpuname=Ingenic XBurst II cputype=47
> 

now:

Starting FDT kernel 80936b08(-2, 87ff9000, 00000000, 0);...

start_kernel: start
start_kernel: after set_task_stack_end_magic
start_kernel: after smp_setup_processor_id
start_kernel: after init_vmlinux_build_id
start_kernel: after cgroup_init_early
start_kernel: after local_irq_disable
start_kernel: after boot_cpu_init
start_kernel: after page_address_init
start_kernel: after pr_notice: linux_banner=Linux version 6.15.0-rc4-letux-lx20+ (hns at iMac.local) (mipsel-linux-gnu-gcc (GCC) 6.3.0, GNU ld (GNU Binutils) 2.27) #2385 PREEMPT Mon Apr 28 18:21:31 CEST 2025
start_kernel: after early_security_init
setup_arch: start
cpu_probe: start
cpu_probe: after set_elf_platform
cpu_probe: after read_c0_prid id = 00132000
cpu_probe: after switch: cpuname=Ingenic XBurst II cputype=47
setup_arch: after cpu_probe
setup_arch: after mips_cm_probe
setup_arch: after prom_init
setup_arch: after setup_early_fdc_console
setup_arch: after cpu_report
setup_arch: after check_bugs64_early