On Friday, 31 August 2018 22:10:48 BST Andrew Udvare wrote:
> On 8/31/18 2:41 PM, Mick wrote:
> > What I have not fathomed yet is how to compile into the mach_kernel the
> > vmlinuz and initrd the boot.efi uses to boot linux.  :-/
> 
> (Note that I am making assumptions that the Apple TV 1st gen can be
> treated kind of like a Mac.)

Right, I'm not sure if it can ...


> You probably should try rEFInd to help. You can get rid of it once you
> are comfortable. rEFInd can be avoided:
> 
> https://glandium.org/blog/?p=2830
> 
> This is what I used years back on a MacBook Pro but I was not successful
> in getting an EFI stub to boot correctly. The issue was a bug with USB
> 2/3 initialisation or something at the time in the kernel, which you
> probably won't run into. I had to use the BIOS emulation which you might
> have the ability to do. So it was rEFInd -> BIOS emulation (calls it
> Windows) -> LILO (GRUB didn't work) and then Linux.

Last time I was dual booting into a MacBook Pro a couple of years ago, I think 
I used CONFIG_EFI_STUB on linux and no boot manager at the time.  The 
MacBook's boot manager listed my gentoo bootx64.efi file which booted into 
Linux without any drama.


> Here is what it looked like (holding C at boot time):
> https://i.imgtc.com/jjBY8AF.jpg (OS is macOS, "Windows" CD in the
> picture was just Gentoo live CD).

Yes, I recall a similar picture with my installation at the time.


> Your problem can be made simpler if you have a) no desire to dual-boot
> and b) no disk encryption. This would mean you only have your VFAT
> partition for EFI and your main partition.

Well, this box has a 32bit EFI, for which a special boot.efi[1] binary was 
developed a long time ago to boot a mach_kernel executable.[2]  The 
mach_kernel is compiled to contain a compressed vmlinuz and initrd image for 
the Linux OS.  The /boot partition is on an 'AppleTV Recovery' (AF04) 
partition type with an HFS+ fs.  At least this is how OSMC and from what I 
understand older Gentoo installations were booting these devices.

However, all this was happening 10 years ago.  I don't know if I can bypass 
all this  malarkey and just compile a kernel with an EFI stub and without 
initrd to boot with.

[1] https://www.developerfusion.com/project/24162/atvbootloader/
[2] https://github.com/davilla/atv-bootloader

-- 
Regards,
Mick