[Intel-gfx] [PATCH] drm/i915: Re-enable aliasing PPGTT mode.

[Chris Wilson]

On Mon, Feb 06, 2017 at 04:18:23PM +0800, Zhi Wang wrote:
> Hi Chris:
>     Thanks for the reply! :P Have you also fixed here with your new ideas?
> 
> in intel_lrc:
> 
> static u64 execlists_update_context(struct drm_i915_gem_request *rq)
> {
>         struct intel_context *ce = &rq->ctx->engine[rq->engine->id];
>         struct i915_hw_ppgtt *ppgtt = rq->ctx->ppgtt;  // ---->
> check if we should get ppgtt from dev_priv->mm.aliasing_ppgtt.

Oh dear. Yup, that's a bug.

Can you send a ppgtt = rq->ctx->ppgtt ?: &rq->i915->mm.aliasing_ppgtt;

One day we will bite the bullet and set ctx->ppgtt to be the
aliasing_ppgtt (and maybe even fix it so that we can global_gtt as
appropriate), and then just fix up the more unusual case in execbuf to
bind using vm = global_gtt instead (if aliasing).
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre