i.MX ProcessorsのトピックRe: initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

dilshad_alam — Thu, 18 Jun 2015 12:53:47 GMT

Trying to Bring up Kernel from Git repo.

http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/log/?h=imx_3.14.28_1.0.0_ga

In start_kernel -> setup_arch -> setup_machine_fdt:-> of_flat_dt_match_machine -> of_get_flat_dt_root

unsigned long p = ((unsigned long)initial_boot_params) + be32_to_cpu(initial_boot_params->off_dt_struct); // Accessing initial_boot_params was causing Kernel to Freeze because in new Kernel initial_boot_params was not getting Initialized.

To fix this issue I Ported drivers/of/fdt.c and arch/arm/kernel/devtree.c from working 3.10 kernel. Now Kernel is booting till

[ 0.000000] Memory: 252116K/262144K available (3975K kernel code, 303K rwdata, 1452K rodata, 317K init, 502K bss, 10028K reserved)

Could you please suggest if any patch I am missing for Device tree support in 3.14.28 Kernel

Re: initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

igorpadykov — Mon, 22 Jun 2015 15:21:39 GMT

Hi Dilshad

there is no need to change for freescale reference boards, one needs

to choose correct board files, like imx6q-sabresd.dtb. Example is

described on

Linux on the i.MX6 sabre sd platform in a few commands

Freescale Yocto Project main page

i.MX Yocto Project: Frequently Asked Questions

Best regards

igor

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Re: initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

dilshad_alam — Tue, 23 Jun 2015 04:13:05 GMT

Hi Igor,

I am using different dts file for my Board.With that dts file and 3.10 Kernel its working fine.

But with New kernel 3.14.28 its not working. Thats the reason i ported back drivers/of/fdt.c and arch/arm/kernel/devtree.c files from 3.10 kernel.

Let me know if anything i need to change in my dts file. I have attached my dts files.

Thanks for your time.

Re: initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

igorpadykov — Tue, 23 Jun 2015 05:28:32 GMT

Hi Dilshad

for custom board one can follow attached Freescale_Yocto_Project_User's_Guide.pdf

sect.7 Creating a Custom Board Configuration and BSP_Porting_Guide, in particular

Chapter 2 Configuring the IOMUX Controller

~igor

Re: initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

dilshad_alam — Tue, 23 Jun 2015 07:03:16 GMT

Hi Igor,

Thanks for your reply. It would be great if you can answer one question.

Where does initial_boot_params field gets populated in 3.14.28 kernel. It would be helpful if you answer to specific queries.

Re: initial_boot_params is causing Kernel Freeze in 3.14.28 Kernel

igorpadykov — Tue, 23 Jun 2015 11:59:41 GMT

Hi Dilshad

this is specific linux kernel question -

please post it to kernel.org

Best regards

igor