Re: [PATCH 0/4] xen/arm: Unbreak ACPI

[Elliott Mitchell <ehem+xen@xxxxxxx>]

On Fri, Oct 09, 2020 at 07:15:20PM +0100, Julien Grall wrote:
> On 09/10/2020 15:22, Elliott Mitchell wrote:
> > Finding all the command-line console settings can be a challenge.  I had
> > thought it was supposed to be "console=hvc0 earlycon=hvc0".
> > 
> > With that though I finally have some output which claims to come from the
> > Linux kernel (yay! finally hit this point!).  As we were both guessing,
> > very early kernel panic:
> > 
> > [    0.000000] efi: Getting EFI parameters from FDT:
> > [    0.000000] efi: Can't find 'System Table' in device tree!
> 
> Thank you for sending part of the log. Looking at Linux 5.6 code, the 
> error message is printed by efi_get_fdt_params() (see 
> drivers/firmware/efi.c) when one of the property is missing.
> 
> 'System Table' suggests that Linux wasn't enable to find 
> "linux,uefi-system-table" or "xen,uefi-system-table".
> 
> Xen will only create later. Would it be possible to add some code in 
> __find_uefi_params() to confirm which property Linux thinks is missing?

Trying to rebuild a configuration long after the prior build can be
entertaining.  Finally identified one patch appears to be for 4.19, but
breaks 5.x.  With that and an appropriate adjustment:

[    0.000000] efi: __find_uefi_params(): Missing "linux,uefi-system-table"
[    0.000000] efi: __find_uefi_params(): Missing "linux,uefi-system-table"


Good news is I had been meaning to try a later kernel for a while and
thus tried building a 5.8 kernel.  Once built, the 5.8 kernel booted
successfully.  As such the next issue is the driver for the graphics chip
doesn't function under Xen as of the 5.8 kernel and Xen 4.14.

I can now state I've gotten success with a combination of Julien Grall's
patches and Masami Hiramatsu.  Certainly qualifies for:

Tested-by: Elliott Mitchell <ehem+xen@xxxxxxx>

For all 5 patches.


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