Re: [PATCH v5 1/3] xen: Add files needed for minimal ppc64le build

[Timothy Pearson <tpearson@xxxxxxxxxxxxxxxxxxxxx>]

----- Original Message -----
> From: "Andrew Cooper" <andrew.cooper3@xxxxxxxxxx>
> To: "Shawn Anastasio" <sanastasio@xxxxxxxxxxxxxxxxxxxxx>, 
> xen-devel@xxxxxxxxxxxxxxxxxxxx
> Cc: "Timothy Pearson" <tpearson@xxxxxxxxxxxxxxxxxxxxx>, "George Dunlap" 
> <george.dunlap@xxxxxxxxxx>, "Jan Beulich"
> <jbeulich@xxxxxxxx>, "Julien Grall" <julien@xxxxxxx>, "Stefano Stabellini" 
> <sstabellini@xxxxxxxxxx>, "Wei Liu"
> <wl@xxxxxxx>
> Sent: Tuesday, June 20, 2023 4:21:22 PM
> Subject: Re: [PATCH v5 1/3] xen: Add files needed for minimal ppc64le build

> On 20/06/2023 7:12 pm, Shawn Anastasio wrote:
>> diff --git a/xen/arch/ppc/xen.lds.S b/xen/arch/ppc/xen.lds.S
>> new file mode 100644
>> index 0000000000..f75d9be4ed
>> --- /dev/null
>> +++ b/xen/arch/ppc/xen.lds.S
>> <snip>
>> +/**
>> + * OF's base load address is 0x400000 (XEN_VIRT_START).
>> + * By defining sections this way, we can keep our virtual address base at
>> 0x400000
>> + * while keeping the physical base at 0x0.
>> + *
>> + * Without this, OF incorrectly loads .text at 0x400000 + 0x400000 = 
>> 0x800000.
>> + * Taken from x86/xen.lds.S
>> + */
> 
> Sorry, one last thing.
> 
> What's OF?  Searching around suggests it might be OpenFirmware, but I'm
> not certain if that's applicable in this context either?
> 
> ~Andrew

OF is indeed Open Firmware.  It was mainly used on old Apple machines, but its 
legacy lives on in SLOF (SlimLine Open Firmware) which is the QEMU bootloader 
for the pSeries machine type.