drm/i915: Intel-specific primary plane handling (v8)

Intel hardware allows the primary plane to be disabled independently of
the CRTC.  Provide custom primary plane handling to allow this.

v8:
 - Pin/unpin properly when clipping causes the primary plane to be
   disabled when it has previously been enabled.
 - s/drm_primary_helper_check_update/drm_plane_helper_check_update/
v7:
 - Clip primary plane to invisible when crtc is disabled since
   intel_crtc->config.pipe_src_{w,h} may be garbage otherwise.
 - Unpin old fb before pinning new one in the "just pin and
   return" case that is used when the crtc is disabled.
 - Don't treat implicit disabling of the primary plane (caused by
   clipping) the same way as explicit disabling (caused by fb=0).
   For implicit disables, we should leave the fb set and pinned,
   whereas for explicit disables we need to unpin the fb before
   primary->fb is cleared.
v6:
 - Pass rectangles to primary helper check function and get plane
   visibility back.
 - Wait for pending pageflips on primary plane update/disable.
 - Allow primary plane to be updated while the crtc is disabled (changes
   will take effect when the crtc is re-enabled if modeset passes -1
   for the fb id).
 - Drop WARN() if we try to disable the primary plane when it's
   already been disabled.  This will happen if the crtc gets disabled
   after the primary plane has already been disabled independently.
v5:
 - Use new drm_primary_helper_check_update() helper function to check
   setplane parameter validity.
 - Swap primary plane's pipe for pre-gen4 FBC (caught by Ville Syrjälä)
 - Cleanup primary plane properly on crtc init failure
v4:
 - Don't add a primary_plane field to intel_crtc; that was left over
   from a much earlier iteration of this patch series, but is no longer
   needed/used now that the DRM core primary plane support has been
   merged.
v3:
 - Provide gen-specific primary plane format lists (suggested by Daniel
   Vetter).
 - If the primary plane is already enabled, go ahead and just call the
   primary plane helper to do the update (suggested by Daniel Vetter).
 - Don't try to disable the primary plane on destruction; the DRM layer
   should have already taken care of this for us.
v2:
 - Unpin fb properly on primary plane disable
 - Provide an Intel-specific set of primary plane formats
 - Additional sanity checks on setplane (in line with the checks
   currently being done by the DRM core primary plane helper)

Reviewed-by: Chon Ming Lee <chon.ming.lee@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_display.c

@@ -39,10 +39,37 @@
 #include "i915_trace.h"
 #include <drm/drm_dp_helper.h>
 #include <drm/drm_crtc_helper.h>
+#include <drm/drm_plane_helper.h>
+#include <drm/drm_rect.h>
 #include <linux/dma_remapping.h>
 
+/* Primary plane formats supported by all gen */
+#define COMMON_PRIMARY_FORMATS \
+	DRM_FORMAT_C8, \
+	DRM_FORMAT_RGB565, \
+	DRM_FORMAT_XRGB8888, \
+	DRM_FORMAT_ARGB8888
+
+/* Primary plane formats for gen <= 3 */
+static const uint32_t intel_primary_formats_gen2[] = {
+	COMMON_PRIMARY_FORMATS,
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_ARGB1555,
+};
+
+/* Primary plane formats for gen >= 4 */
+static const uint32_t intel_primary_formats_gen4[] = {
+	COMMON_PRIMARY_FORMATS, \
+	DRM_FORMAT_XBGR8888,
+	DRM_FORMAT_ABGR8888,
+	DRM_FORMAT_XRGB2101010,
+	DRM_FORMAT_ARGB2101010,
+	DRM_FORMAT_XBGR2101010,
+	DRM_FORMAT_ABGR2101010,
+};
+
 #define DIV_ROUND_CLOSEST_ULL(ll, d)	\
-	({ unsigned long long _tmp = (ll)+(d)/2; do_div(_tmp, d); _tmp; })
+({ unsigned long long _tmp = (ll)+(d)/2; do_div(_tmp, d); _tmp; })
 
 static void intel_increase_pllclock(struct drm_crtc *crtc);
 static void intel_crtc_update_cursor(struct drm_crtc *crtc, bool on);
@@ -10977,17 +11004,216 @@ static void intel_shared_dpll_init(struct drm_device *dev)
 	BUG_ON(dev_priv->num_shared_dpll > I915_NUM_PLLS);
 }
 
+static int
+intel_primary_plane_disable(struct drm_plane *plane)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_plane *intel_plane = to_intel_plane(plane);
+	struct intel_crtc *intel_crtc;
+
+	if (!plane->fb)
+		return 0;
+
+	BUG_ON(!plane->crtc);
+
+	intel_crtc = to_intel_crtc(plane->crtc);
+
+	/*
+	 * Even though we checked plane->fb above, it's still possible that
+	 * the primary plane has been implicitly disabled because the crtc
+	 * coordinates given weren't visible, or because we detected
+	 * that it was 100% covered by a sprite plane.  Or, the CRTC may be
+	 * off and we've set a fb, but haven't actually turned on the CRTC yet.
+	 * In either case, we need to unpin the FB and let the fb pointer get
+	 * updated, but otherwise we don't need to touch the hardware.
+	 */
+	if (!intel_crtc->primary_enabled)
+		goto disable_unpin;
+
+	intel_crtc_wait_for_pending_flips(plane->crtc);
+	intel_disable_primary_hw_plane(dev_priv, intel_plane->plane,
+				       intel_plane->pipe);
+
+disable_unpin:
+	intel_unpin_fb_obj(to_intel_framebuffer(plane->fb)->obj);
+	plane->fb = NULL;
+
+	return 0;
+}
+
+static int
+intel_primary_plane_setplane(struct drm_plane *plane, struct drm_crtc *crtc,
+			     struct drm_framebuffer *fb, int crtc_x, int crtc_y,
+			     unsigned int crtc_w, unsigned int crtc_h,
+			     uint32_t src_x, uint32_t src_y,
+			     uint32_t src_w, uint32_t src_h)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+	struct intel_plane *intel_plane = to_intel_plane(plane);
+	struct drm_rect dest = {
+		/* integer pixels */
+		.x1 = crtc_x,
+		.y1 = crtc_y,
+		.x2 = crtc_x + crtc_w,
+		.y2 = crtc_y + crtc_h,
+	};
+	struct drm_rect src = {
+		/* 16.16 fixed point */
+		.x1 = src_x,
+		.y1 = src_y,
+		.x2 = src_x + src_w,
+		.y2 = src_y + src_h,
+	};
+	const struct drm_rect clip = {
+		/* integer pixels */
+		.x2 = intel_crtc->active ? intel_crtc->config.pipe_src_w : 0,
+		.y2 = intel_crtc->active ? intel_crtc->config.pipe_src_h : 0,
+	};
+	bool visible;
+	int ret;
+
+	ret = drm_plane_helper_check_update(plane, crtc, fb,
+					    &src, &dest, &clip,
+					    DRM_PLANE_HELPER_NO_SCALING,
+					    DRM_PLANE_HELPER_NO_SCALING,
+					    false, true, &visible);
+
+	if (ret)
+		return ret;
+
+	/*
+	 * If the CRTC isn't enabled, we're just pinning the framebuffer,
+	 * updating the fb pointer, and returning without touching the
+	 * hardware.  This allows us to later do a drmModeSetCrtc with fb=-1 to
+	 * turn on the display with all planes setup as desired.
+	 */
+	if (!crtc->enabled) {
+		/*
+		 * If we already called setplane while the crtc was disabled,
+		 * we may have an fb pinned; unpin it.
+		 */
+		if (plane->fb)
+			intel_unpin_fb_obj(to_intel_framebuffer(plane->fb)->obj);
+
+		/* Pin and return without programming hardware */
+		return intel_pin_and_fence_fb_obj(dev,
+						  to_intel_framebuffer(fb)->obj,
+						  NULL);
+	}
+
+	intel_crtc_wait_for_pending_flips(crtc);
+
+	/*
+	 * If clipping results in a non-visible primary plane, we'll disable
+	 * the primary plane.  Note that this is a bit different than what
+	 * happens if userspace explicitly disables the plane by passing fb=0
+	 * because plane->fb still gets set and pinned.
+	 */
+	if (!visible) {
+		/*
+		 * Try to pin the new fb first so that we can bail out if we
+		 * fail.
+		 */
+		if (plane->fb != fb) {
+			ret = intel_pin_and_fence_fb_obj(dev,
+							 to_intel_framebuffer(fb)->obj,
+							 NULL);
+			if (ret)
+				return ret;
+		}
+
+		if (intel_crtc->primary_enabled)
+			intel_disable_primary_hw_plane(dev_priv,
+						       intel_plane->plane,
+						       intel_plane->pipe);
+
+
+		if (plane->fb != fb)
+			if (plane->fb)
+				intel_unpin_fb_obj(to_intel_framebuffer(plane->fb)->obj);
+
+		return 0;
+	}
+
+	ret = intel_pipe_set_base(crtc, src.x1, src.y1, fb);
+	if (ret)
+		return ret;
+
+	if (!intel_crtc->primary_enabled)
+		intel_enable_primary_hw_plane(dev_priv, intel_crtc->plane,
+					      intel_crtc->pipe);
+
+	return 0;
+}
+
+static void intel_primary_plane_destroy(struct drm_plane *plane)
+{
+	struct intel_plane *intel_plane = to_intel_plane(plane);
+	drm_plane_cleanup(plane);
+	kfree(intel_plane);
+}
+
+static const struct drm_plane_funcs intel_primary_plane_funcs = {
+	.update_plane = intel_primary_plane_setplane,
+	.disable_plane = intel_primary_plane_disable,
+	.destroy = intel_primary_plane_destroy,
+};
+
+static struct drm_plane *intel_primary_plane_create(struct drm_device *dev,
+						    int pipe)
+{
+	struct intel_plane *primary;
+	const uint32_t *intel_primary_formats;
+	int num_formats;
+
+	primary = kzalloc(sizeof(*primary), GFP_KERNEL);
+	if (primary == NULL)
+		return NULL;
+
+	primary->can_scale = false;
+	primary->max_downscale = 1;
+	primary->pipe = pipe;
+	primary->plane = pipe;
+	if (HAS_FBC(dev) && INTEL_INFO(dev)->gen < 4)
+		primary->plane = !pipe;
+
+	if (INTEL_INFO(dev)->gen <= 3) {
+		intel_primary_formats = intel_primary_formats_gen2;
+		num_formats = ARRAY_SIZE(intel_primary_formats_gen2);
+	} else {
+		intel_primary_formats = intel_primary_formats_gen4;
+		num_formats = ARRAY_SIZE(intel_primary_formats_gen4);
+	}
+
+	drm_universal_plane_init(dev, &primary->base, 0,
+				 &intel_primary_plane_funcs,
+				 intel_primary_formats, num_formats,
+				 DRM_PLANE_TYPE_PRIMARY);
+	return &primary->base;
+}
+
 static void intel_crtc_init(struct drm_device *dev, int pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_crtc *intel_crtc;
-	int i;
+	struct drm_plane *primary;
+	int i, ret;
 
 	intel_crtc = kzalloc(sizeof(*intel_crtc), GFP_KERNEL);
 	if (intel_crtc == NULL)
 		return;
 
-	drm_crtc_init(dev, &intel_crtc->base, &intel_crtc_funcs);
+	primary = intel_primary_plane_create(dev, pipe);
+	ret = drm_crtc_init_with_planes(dev, &intel_crtc->base, primary,
+					NULL, &intel_crtc_funcs);
+	if (ret) {
+		drm_plane_cleanup(primary);
+		kfree(intel_crtc);
+		return;
+	}
 
 	drm_mode_crtc_set_gamma_size(&intel_crtc->base, 256);
 	for (i = 0; i < 256; i++) {