[U-Boot] Booting Linux kernel on x86_64

[Andy Shevchenko]

On Fri, Aug 9, 2019 at 6:52 PM Ryan Wilkins <ryan at elevated-networks.com> wrote:
>
> Hello,
>
> I’m trying to get u-boot 2019.04 to execute the Linux 4.19.55 kernel from u-boot on a generic Core i5 with 8 GB RAM and having issues.  The kernel that I’m trying to boot will boot fine from GRUB so I know it works but starting from u-boot just shows “Starting kernel” and the system appears to freeze.
>
> my bootcmd is
>   scsi reset; ext2load scsi 0:5 0x04000000 bzImage; ext2load scsi 0:5 0x08000000 rootfs.cpio.uboot; zboot 04000000 0 08000000 ${filesize}
>
> The kernel bzip2 compressed file size is around 6 MB and the rootfs is about 125 MB.
> The kernel and rootfs are loaded in OK and running zboot finds the kernel OK.  The rootfs is a gzip compressed cpio with uboot wrapper.  I’m using buildroot 2019.02 to create the system and rootfs.
>
> You might be asking why not just go with GRUB instead and the reason is the company I’m working for has a lot of ARM-based devices out that all utilize u-boot of which I’m quite familiar with, but this particular project is based on the Intel Core i5.  It was decided to keep the system as similar as possible to the ARM-based boards to keep support differences as minimal as possible.  A number of utilities that we have already written are meant to interact with the u-boot environment and depend on it.
>
> I realize this is rather sparse with information, but rather than make an unnecessarily long email does anyone have any ideas of what to check or try or requests for more information?
>
> Thanks in advance for any assistance.

You may try to enable 'earlyprintk=efi' (newer kernels have different
approach, i.e. 'earlycon=efifb') and also add 'keep_bootcon' to see if
the problem is at the beginning or ending stages of boot process.



-- 
With Best Regards,
Andy Shevchenko