[PATCH 0/3] Fix XIP boot and make XIP testable in QEMU

[Palmer Dabbelt]

On Tue, 12 Dec 2023 07:14:54 PST (-0800), Conor Dooley wrote:
>
> Firstly, no html mails, they're rejected by the lists and break people's
> mail flows.
>
> On Tue, Dec 12, 2023 at 03:16:13PM +0100, Vitaly Wool wrote:
>> tis 12 dec. 2023 kl. 14:23 skrev Conor Dooley <conor.dooley at microchip.com<mailto:conor.dooley at microchip.com>>:
>> > On Tue, Dec 12, 2023 at 02:01:11PM +0100, Frederik Haxel wrote:
>> > > XIP boot seems to be broken for some time now. A likely reason why no one
>> > > seems to have noticed this is that XIP is more difficult to test, as it is
>> > > currently not easily testable with QEMU.
>> > >
>> > > These patches fix the XIP boot and allow an XIP build without BUILTIN_DTB,
>> > > which in turn makes it easier to test an image with the QEMU virt machine.
>> > 
>> > 
>> > Are you actually using XIP in something other than QEMU? The fact that
>> > some of the blamed fixes are over 18 months old suggests that you are
>> > not actively using XIP builds of the mainline kernel.
>> > There is a desire to remove XIP support (among other things), so if you
>> > do actually have a use case for it, speak up.
>> 
>> Yes, we surely do, on K210 for instance. It’s using an older kernel and
>
> The k210 and nommu are on the block for removal too :)
> Is your use case for either the k210 or XIP something other than
> "ooh this works"? 

Ya, if someone is actually using the XIP (and/or K210 or NOMMU) stuff 
then I'm fine keeping it.  We'd just figured it was probably broken 
because nobody'd been posting patches and we didn't have any automated 
tests.  Looks like it was broken, which is always a pretty strong sign 
it's not being used.

>> I haven’t checked the mainline status for a while
>
> I figured that when the request I sent asking if you could test XIP was
> ignored. We've been 50-50 on whether it has been broken since Alex put
> the dtb in the fixmap ~9 months ago.
>
>> but it is likely that I will come up with some XIP updates
>> before Christmas.
>
> May I ask what you intend updating?
>
> Cheers,
> Conor.