[Intel-gfx] [PATCH 06/31] drm/i915/execlists: Unify CSB access pointers

[Chris Wilson]

Quoting Tvrtko Ursulin (2018-06-27 10:52:45)
> 
> On 25/06/2018 10:48, Chris Wilson wrote:
> > @@ -1109,16 +1089,11 @@ static void process_csb(struct intel_engine_cs *engine)
> >               } else {
> >                       port_set(port, port_pack(rq, count));
> >               }
> > -     }
> > +     } while (head != tail);
> >   
> > -     if (head != execlists->csb_head) {
> > -             execlists->csb_head = head;
> > -             writel(_MASKED_FIELD(GEN8_CSB_READ_PTR_MASK, head << 8),
> > -                    i915->regs + i915_mmio_reg_offset(RING_CONTEXT_STATUS_PTR(engine)));
> > -     }
> > -
> > -     if (unlikely(fw))
> > -             intel_uncore_forcewake_put(i915, execlists->fw_domains);
> > +     writel(_MASKED_FIELD(GEN8_CSB_READ_PTR_MASK, head << 8),
> > +            execlists->csb_read);
> 
> Continuing from the last round - so what to do with this one? It does 
> need forcewake. So I think it needs to go if we are claiming there is no 
> mmio any longer.

From last round, we decided it didn't, or at least concluded the
(from the lack of) evidence that it does not, because we are not using
forcewake right now...
-Chris