[Intel-gfx] [PATCH v8 08/12] drm/i915/uc: Fully sanitize uC within intel_uc_fini_hw

[Michal Wajdeczko]

On Mon, 09 Apr 2018 14:47:24 +0200, Chris Wilson  
<chris at chris-wilson.co.uk> wrote:

> Quoting Michal Wajdeczko (2018-04-09 13:23:28)
>> As we always call intel_uc_sanitize after every call to
>> intel_uc_fini_hw we may drop redundant call and sanitize
>> uC from the fini_hw function.
>>
>> Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
>> Cc: Sagar Arun Kamble <sagar.a.kamble at intel.com>
>> Cc: Chris Wilson <chris at chris-wilson.co.uk>
>
> Not that it matters, since doing it before losing control or on resume
> is the same from our pov, but I've always pencilled in sanitize as being
> done on takeover (i.e. before init).

In intel_uc_init_hw we are already doing some semi-sanitization (thanks
to __intel_uc_reset_hw), but maybe to be more explicit, we should add
call to __uc_sanitize() in intel_uc_init_mmio() ?

> Why do you favour after fini?

Hmm, not at all, I would call it just more explicit

>
> Gut feeling prefers keeping it as a separate step rather rolling it up
> into init/fini. But that's just because before we did sanitize
> elsewhere, we had many strange bugs and those bugs have left their
> scars (so I like seeing sanitize, it reminds me of dead bugs).

As now we have symmetrical inits/finis that cover all critical paths,
I don't think we need separate 'sanitize' step that could be called
any time/any place.

I assume extra __sanitize in uc_init_mmio should be enough reminder.

/michal