[Intel-gfx] [CI] drm/i915: Add I915_PARAM_MMAP_GTT_VERSION to advertise unlimited mmaps

[Chris Wilson]

Now that we have working partial VMA and faulting support for all
objects, including fence support, advertise to userspace that it can
take advantage of unlimited GGTT mmaps.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_drv.c | 8 ++++++++
 drivers/gpu/drm/i915/i915_gem.c | 3 +++
 include/uapi/drm/i915_drm.h     | 1 +
 3 files changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 1d2230f7b749..a3fcd5ed913b 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -355,6 +355,14 @@ static int i915_getparam(struct drm_device *dev, void *data,
 	case I915_PARAM_MIN_EU_IN_POOL:
 		value = INTEL_INFO(dev)->min_eu_in_pool;
 		break;
+	case I915_PARAM_MMAP_GTT_VERSION:
+		/* undefined -	Objects have to be smaller than aperture,
+		 *		all simultaneous users have to fit within the
+		 *		available space within the aperture.
+		 *         1 -	Objects can be any size, and X,Y or untiled
+		 */
+		value = 1;
+		break;
 	default:
 		DRM_DEBUG("Unknown parameter %d\n", param->param);
 		return -EINVAL;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 04607d4115d6..03db668dd1c5 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1694,6 +1694,9 @@ static unsigned int tile_row_pages(struct drm_i915_gem_object *obj)
  * from the GTT and/or fence registers to make room.  So performance may
  * suffer if the GTT working set is large or there are few fence registers
  * left.
+ *
+ * The current feature set supported by i915_gem_fault() and thus GTT mmaps
+ * is exposed via I915_PARAM_MMAP_GTT_VERSION.
  */
 int i915_gem_fault(struct vm_area_struct *area, struct vm_fault *vmf)
 {
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h
index 5501fe83ed92..03725fe89859 100644
--- a/include/uapi/drm/i915_drm.h
+++ b/include/uapi/drm/i915_drm.h
@@ -387,6 +387,7 @@ typedef struct drm_i915_irq_wait {
 #define I915_PARAM_HAS_EXEC_SOFTPIN	 37
 #define I915_PARAM_HAS_POOLED_EU	 38
 #define I915_PARAM_MIN_EU_IN_POOL	 39
+#define I915_PARAM_MMAP_GTT_VERSION	 40
 
 typedef struct drm_i915_getparam {
 	__s32 param;
-- 
2.9.3