On Wed, Mar 22, 2017 at 03:59:21PM +0000, Marc Zyngier wrote:
> [Sorry, sent too quickly]
>
[ ... ]
> >> struct arch_timer_erratum_workaround {
> >> - const char *id; /* Indicate the Erratum ID */
> >> + enum arch_timer_erratum_match_type match_type;
> >
> > Putting the match_fn instead will be much more simpler and the code won't
> > have to deal with ate_match_type, no ?
>
> I'm not sure about the "much simpler" aspect. Each function is not
> necessarily standalone (see patches 8 and 13 for example, dealing with
> CPU-local defects).
Why not write always errata on a per cpu basis ? So there is no need to go
through global/local (at the timer level).
You have been probably looking at this much longer than me and perhaps I'm
missing something. However, I think we can find a way to simplify the approach.
Give me one day to see if I'm right.
> Also, given that we have two architectures to cater for, as well as two
> firmware interfaces, it makes more sense (at least to me) to have
> something that doesn't require to define a bunch of empty stubs (we
> already have too many of them) depending on arm vs arm64, DT vs ACPI,
> errata handling enabled vs disabled.
That is a fair point.
> We're sidestepping this at the moment because it all lives under one
> single config option that cannot be enabled from 32bit, but I hope to
> change that.
Ok, that sounds good.
Thanks for proposing something to deal elegantly with the errata.
-- Daniel
> > [ ... ]
> >
> >> +static void arch_timer_check_ool_workaround(enum
> >> arch_timer_erratum_match_type type,
> >> + void *arg)
> >> +{
> >> + const struct arch_timer_erratum_workaround *wa;
> >> + ate_match_fn_t match_fn = NULL;
> >> +
> >> + if (static_branch_unlikely(&arch_timer_read_ool_enabled))
> >> + return;
> >> +
> >
> > Why is this check necessary ?
>
> We don't allow cumulative workarounds at this stage. This restriction
> gets lifted (to some extent) later in the series.
>
> Thanks,
>
> M.
> --
> Jazz is not dead. It just smells funny...
--
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog
