[PATCH v3 2/9] arm64/sysreg: Update ID_AA64ISAR3_EL1 to DDI0601 2024-09

[Mark Brown]

On Wed, Dec 11, 2024 at 10:40:15PM +0000, Will Deacon wrote:
> On Tue, Dec 10, 2024 at 06:43:05PM +0000, Mark Brown wrote:

> > Yes, the issues here are not technical ones.  Though there are some
> > complications -  eg, IIRC the XML doesn't encode the signedness of
> > fields like we do and there's areas where we've deliberately diverged.
> > Given the amount of review I end up having to do of sysreg changes your
> > reasoning is especially apparent to me.  I've passed this feedback on
> > (again).

> One thing we _could_ do is have a tool (in-tree) that takes two copies
> of the sysreg file (i.e. before and after applying a diff) along with a
> copy of the XML and, for the the new fields being added, shows how the
> XML represents those compared to the diff. It should then be relatively
> straightforward to flag the use of an unallocated encoding (like we had
> here) and also things like assigning a field name to a RES0 region.

> So this wouldn't be generating the patches from the XML, but more like
> using the XML as an oracle in a linter.

That'd be useful, yes - unfortunately I think that's still something I
can't work on myself at the moment for the above mentioned non-technical
reasons.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 488 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20241212/467ed514/attachment.sig>