[Intel-gfx] [PATCH 05/19] drm/i915: Use i915_vma_pin_iomap on the ringbuffer object

[Joonas Lahtinen]

On ke, 2016-04-20 at 19:42 +0100, Chris Wilson wrote:
> Similarly to i915_gem_object_pin_map on LLC platforms, we can
> use the new VMA based io mapping on !LLC to amoritize the cost
> of ringbuffer pinning and unpinning.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>

Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>

> ---
>  drivers/gpu/drm/i915/intel_ringbuffer.c | 16 +++++++++-------
>  1 file changed, 9 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 245386e20c52..27ba15acae1e 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -2084,20 +2084,23 @@ static int init_phys_status_page(struct intel_engine_cs *engine)
>  
>  void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
>  {
> +	GEM_BUG_ON(ringbuf->vma == NULL);
> +	GEM_BUG_ON(ringbuf->virtual_start == NULL);
> +
>  	if (HAS_LLC(ringbuf->obj->base.dev) && !ringbuf->obj->stolen)
>  		i915_gem_object_unpin_map(ringbuf->obj);
>  	else
> -		iounmap(ringbuf->virtual_start);
> +		i915_vma_unpin_iomap(ringbuf->vma);
>  	ringbuf->virtual_start = NULL;
> -	ringbuf->vma = NULL;
> +
>  	i915_gem_object_ggtt_unpin(ringbuf->obj);
> +	ringbuf->vma = NULL;
>  }
>  
>  int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
>  				     struct intel_ringbuffer *ringbuf)
>  {
>  	struct drm_i915_private *dev_priv = to_i915(dev);
> -	struct i915_ggtt *ggtt = &dev_priv->ggtt;
>  	struct drm_i915_gem_object *obj = ringbuf->obj;
>  	/* Ring wraparound at offset 0 sometimes hangs. No idea why. */
>  	unsigned flags = PIN_OFFSET_BIAS | 4096;
> @@ -2131,10 +2134,9 @@ int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
>  		/* Access through the GTT requires the device to be awake. */
>  		assert_rpm_wakelock_held(dev_priv);
>  
> -		addr = ioremap_wc(ggtt->mappable_base +
> -				  i915_gem_obj_ggtt_offset(obj), ringbuf->size);
> -		if (addr == NULL) {
> -			ret = -ENOMEM;
> +		addr = i915_vma_pin_iomap(i915_gem_obj_to_ggtt(obj));
> +		if (IS_ERR(addr)) {
> +			ret = PTR_ERR(addr);
>  			goto err_unpin;
>  		}
>  	}
-- 
Joonas Lahtinen
Open Source Technology Center
Intel Corporation