[RFCv3 03/14] drm: Add primary plane helpers

[Matt Roper <matthew.d.roper@intel.com>]

When we expose non-overlay planes to userspace, they will become
accessible via standard userspace plane API's.  We should be able to
handle the standard plane operations against primary planes in a generic
way via the page flip handler and modeset handler.

Drivers that can program primary planes more efficiently, that want to
use their own primary plane structure to track additional information,
or that don't have the limitations assumed by the helpers are free to
provide their own implementation of some or all of these handlers.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
---
 drivers/gpu/drm/drm_crtc.c | 288 +++++++++++++++++++++++++++++++++++++++------
 include/drm/drm_crtc.h     |  81 +++++++++++++
 2 files changed, 330 insertions(+), 39 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 0983996..db54ae9 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1118,6 +1118,255 @@ void drm_plane_force_disable(struct drm_plane *plane)
 }
 EXPORT_SYMBOL(drm_plane_force_disable);
 
+/*
+ * Checks that the framebuffer is big enough for the CRTC viewport
+ * (x, y, hdisplay, vdisplay)
+ */
+static int drm_crtc_check_viewport(const struct drm_crtc *crtc,
+				   int x, int y,
+				   const struct drm_display_mode *mode,
+				   const struct drm_framebuffer *fb)
+
+{
+	int hdisplay, vdisplay;
+
+	hdisplay = mode->hdisplay;
+	vdisplay = mode->vdisplay;
+
+	if (drm_mode_is_stereo(mode)) {
+		struct drm_display_mode adjusted = *mode;
+
+		drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE);
+		hdisplay = adjusted.crtc_hdisplay;
+		vdisplay = adjusted.crtc_vdisplay;
+	}
+
+	if (crtc->invert_dimensions)
+		swap(hdisplay, vdisplay);
+
+	if (hdisplay > fb->width ||
+	    vdisplay > fb->height ||
+	    x > fb->width - hdisplay ||
+	    y > fb->height - vdisplay) {
+		DRM_DEBUG_KMS("Invalid fb size %ux%u for CRTC viewport %ux%u+%d+%d%s.\n",
+			      fb->width, fb->height, hdisplay, vdisplay, x, y,
+			      crtc->invert_dimensions ? " (inverted)" : "");
+		return -ENOSPC;
+	}
+
+	return 0;
+}
+
+/*
+ * Returns the connectors currently associated with a CRTC.  This function
+ * should be called twice:  once with a NULL connector list to retrieve
+ * the list size, and once with the properly allocated list to be filled in.
+ */
+static int get_connectors_for_crtc(struct drm_crtc *crtc,
+				   struct drm_connector **connector_list,
+				   int num_connectors)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_connector *connector;
+	int count = 0;
+
+	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
+		if (connector->encoder && connector->encoder->crtc == crtc) {
+			if (connector_list != NULL && count < num_connectors)
+				*(connector_list++) = connector;
+
+			count++;
+		}
+
+	return count;
+}
+
+/**
+ * drm_primary_helper_update() - Helper for primary plane update
+ * @plane: plane object to update
+ * @crtc: owning CRTC of owning plane
+ * @fb: framebuffer to flip onto plane
+ * @crtc_x: x offset of primary plane on crtc
+ * @crtc_y: y offset of primary plane on crtc
+ * @crtc_w: width of primary plane rectangle on crtc
+ * @crtc_h: height of primary plane rectangle on crtc
+ * @src_x: x offset of @fb for panning
+ * @src_y: y offset of @fb for panning
+ * @src_w: width of source rectangle in @fb
+ * @src_h: height of source rectangle in @fb
+ *
+ * Provides a default plane update handler for primary planes.  This is handler
+ * is called in response to a userspace SetPlane operation on the plane with a
+ * non-NULL framebuffer.  We call the driver's pageflip handler to update the
+ * framebuffer.
+ *
+ * SetPlane() on a primary plane of a disabled CRTC is not supported, and will
+ * return an error.
+ *
+ * Note that we assume most hardware can't reposition or scale the primary
+ * plane, so we require that crtc_x = crtc_y = 0 and that src_w/src_h match the
+ * current mode.  Drivers for hardware that don't have these restrictions can
+ * provide their own implementation rather than using this helper.
+ *
+ * RETURNS:
+ * Zero on success, error code on failure
+ */
+int drm_primary_helper_update(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_mode_set set = {
+		.crtc = crtc,
+		.fb = fb,
+		.mode = &crtc->mode,
+		.x = crtc_x,
+		.y = crtc_y,
+	};
+	struct drm_connector **connector_list;
+	struct drm_framebuffer *tmpfb;
+	int num_connectors, ret;
+
+	/* setplane API takes shifted source rectangle values; unshift them */
+	src_x >>= 16;
+	src_y >>= 16;
+	src_w >>= 16;
+	src_h >>= 16;
+
+	/* Primary planes are locked to their owning CRTC */
+	if (plane->possible_crtcs != drm_crtc_mask(crtc)) {
+		DRM_DEBUG_KMS("Cannot change primary plane CRTC\n");
+		return -EINVAL;
+	}
+
+	if (!crtc->enabled) {
+		DRM_DEBUG_KMS("Cannot update primary plane of a disabled CRTC.\n");
+		return -EINVAL;
+	}
+
+	ret = drm_crtc_check_viewport(crtc, crtc_x, crtc_y, &crtc->mode, fb);
+	if (ret)
+		return ret;
+
+	/* Find current connectors for CRTC */
+	num_connectors = get_connectors_for_crtc(crtc, NULL, 0);
+	BUG_ON(num_connectors == 0);
+	connector_list = kzalloc(num_connectors * sizeof(*connector_list),
+				 GFP_KERNEL);
+	if (!connector_list)
+		return -ENOMEM;
+	get_connectors_for_crtc(crtc, connector_list, num_connectors);
+
+	set.connectors = connector_list;
+	set.num_connectors = num_connectors;
+
+	/*
+	 * set_config() adjusts crtc->primary->fb; however the DRM setplane
+	 * code that called us expects to handle the framebuffer update and
+	 * reference counting; save and restore the current fb before
+	 * calling it.
+	 */
+	tmpfb = plane->fb;
+	ret = crtc->funcs->set_config(&set);
+	plane->fb = tmpfb;
+
+	kfree(connector_list);
+	return ret;
+}
+EXPORT_SYMBOL(drm_primary_helper_update);
+
+/**
+ * drm_primary_helper_disable() - Helper for primary plane disable
+ * @plane: plane to disable
+ *
+ * Provides a default plane disable handler for primary planes.  This is handler
+ * is called in response to a userspace SetPlane operation on the plane with a
+ * NULL framebuffer parameter.  We call the driver's modeset handler with a NULL
+ * framebuffer to disable the CRTC.
+ *
+ * Note that some hardware may be able to disable the primary plane without
+ * disabling the whole CRTC.  Drivers for such hardware should provide their
+ * own disable handler that disables just the primary plane (and they'll likely
+ * need to provide their own update handler as well to properly re-enable a
+ * disabled primary plane).
+ *
+ * RETURNS:
+ * Zero on success, error code on failure
+ */
+int drm_primary_helper_disable(struct drm_plane *plane)
+{
+	struct drm_mode_set set = {
+		.crtc = plane->crtc,
+		.fb = NULL,
+	};
+
+	if (plane->crtc == NULL || plane->fb == NULL)
+		/* Already disabled */
+		return 0;
+
+	return plane->crtc->funcs->set_config(&set);
+}
+EXPORT_SYMBOL(drm_primary_helper_disable);
+
+/**
+ * drm_primary_helper_destroy() - Helper for primary plane destruction
+ * @plane: plane to destroy
+ *
+ * Provides a default plane destroy handler for primary planes.  This handler
+ * is called during CRTC destruction.  We disable the primary plane, remove
+ * it from the DRM plane list, and deallocate the plane structure.
+ */
+void drm_primary_helper_destroy(struct drm_plane *plane)
+{
+	plane->funcs->disable_plane(plane);
+	drm_plane_cleanup(plane);
+	kfree(plane);
+}
+EXPORT_SYMBOL(drm_primary_helper_destroy);
+
+const struct drm_plane_funcs drm_primary_helper_funcs = {
+	.update_plane = drm_primary_helper_update,
+	.disable_plane = drm_primary_helper_disable,
+	.destroy = drm_primary_helper_destroy,
+};
+EXPORT_SYMBOL(drm_primary_helper_funcs);
+
+/**
+ * drm_primary_helper_create_plane() - Create a generic primary plane
+ * @dev: drm device
+ *
+ * Allocates and initializes a primary plane that can be used with the primary
+ * plane helpers.  Drivers that wish to use driver-specific plane structures or
+ * provide custom handler functions may perform their own allocation and
+ * initialization rather than calling this function.
+ */
+struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev)
+{
+	struct drm_plane *primary;
+	int ret;
+
+	primary = kzalloc(sizeof(*primary), GFP_KERNEL);
+	if (primary == NULL) {
+		DRM_DEBUG_KMS("Failed to allocate primary plane\n");
+		return NULL;
+	}
+
+	/* possible_crtc's will be filled in later by crtc_init */
+	ret = drm_plane_init(dev, primary, 0, &drm_primary_helper_funcs,
+			     legacy_modeset_formats,
+			     ARRAY_SIZE(legacy_modeset_formats),
+			     DRM_PLANE_TYPE_PRIMARY);
+	if (ret) {
+		kfree(primary);
+		primary = NULL;
+	}
+
+	return primary;
+}
+EXPORT_SYMBOL(drm_primary_helper_create_plane);
+
 static int drm_mode_create_standard_connector_properties(struct drm_device *dev)
 {
 	struct drm_property *edid;
@@ -2185,45 +2434,6 @@ int drm_mode_set_config_internal(struct drm_mode_set *set)
 }
 EXPORT_SYMBOL(drm_mode_set_config_internal);
 
-/*
- * Checks that the framebuffer is big enough for the CRTC viewport
- * (x, y, hdisplay, vdisplay)
- */
-static int drm_crtc_check_viewport(const struct drm_crtc *crtc,
-				   int x, int y,
-				   const struct drm_display_mode *mode,
-				   const struct drm_framebuffer *fb)
-
-{
-	int hdisplay, vdisplay;
-
-	hdisplay = mode->hdisplay;
-	vdisplay = mode->vdisplay;
-
-	if (drm_mode_is_stereo(mode)) {
-		struct drm_display_mode adjusted = *mode;
-
-		drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE);
-		hdisplay = adjusted.crtc_hdisplay;
-		vdisplay = adjusted.crtc_vdisplay;
-	}
-
-	if (crtc->invert_dimensions)
-		swap(hdisplay, vdisplay);
-
-	if (hdisplay > fb->width ||
-	    vdisplay > fb->height ||
-	    x > fb->width - hdisplay ||
-	    y > fb->height - vdisplay) {
-		DRM_DEBUG_KMS("Invalid fb size %ux%u for CRTC viewport %ux%u+%d+%d%s.\n",
-			      fb->width, fb->height, hdisplay, vdisplay, x, y,
-			      crtc->invert_dimensions ? " (inverted)" : "");
-		return -ENOSPC;
-	}
-
-	return 0;
-}
-
 /**
  * drm_mode_setcrtc - set CRTC configuration
  * @dev: drm device for the ioctl
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index e69ada8..f43fa92 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -581,6 +581,87 @@ struct drm_plane {
 	enum drm_plane_type type;
 };
 
+extern int drm_primary_helper_update(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);
+extern int drm_primary_helper_disable(struct drm_plane *plane);
+extern void drm_primary_helper_destroy(struct drm_plane *plane);
+extern const struct drm_plane_funcs drm_primary_helper_funcs;
+extern struct drm_plane *drm_primary_helper_create_plane(struct drm_device *dev);
+
+/*
+ * This is the list of formats that have historically been accepted by the
+ * modeset API.  The primary plane helpers use this list by default, but
+ * individual drivers may provide their own primary plane initialization
+ * that provides a more hw-specific format list.
+ */
+const static uint32_t legacy_modeset_formats[] = {
+       DRM_FORMAT_C8,
+       DRM_FORMAT_RGB332,
+       DRM_FORMAT_BGR233,
+       DRM_FORMAT_XRGB4444,
+       DRM_FORMAT_XBGR4444,
+       DRM_FORMAT_RGBX4444,
+       DRM_FORMAT_BGRX4444,
+       DRM_FORMAT_ARGB4444,
+       DRM_FORMAT_ABGR4444,
+       DRM_FORMAT_RGBA4444,
+       DRM_FORMAT_BGRA4444,
+       DRM_FORMAT_XRGB1555,
+       DRM_FORMAT_XBGR1555,
+       DRM_FORMAT_RGBX5551,
+       DRM_FORMAT_BGRX5551,
+       DRM_FORMAT_ARGB1555,
+       DRM_FORMAT_ABGR1555,
+       DRM_FORMAT_RGBA5551,
+       DRM_FORMAT_BGRA5551,
+       DRM_FORMAT_RGB565,
+       DRM_FORMAT_BGR565,
+       DRM_FORMAT_RGB888,
+       DRM_FORMAT_BGR888,
+       DRM_FORMAT_XRGB8888,
+       DRM_FORMAT_XBGR8888,
+       DRM_FORMAT_RGBX8888,
+       DRM_FORMAT_BGRX8888,
+       DRM_FORMAT_ARGB8888,
+       DRM_FORMAT_ABGR8888,
+       DRM_FORMAT_RGBA8888,
+       DRM_FORMAT_BGRA8888,
+       DRM_FORMAT_XRGB2101010,
+       DRM_FORMAT_XBGR2101010,
+       DRM_FORMAT_RGBX1010102,
+       DRM_FORMAT_BGRX1010102,
+       DRM_FORMAT_ARGB2101010,
+       DRM_FORMAT_ABGR2101010,
+       DRM_FORMAT_RGBA1010102,
+       DRM_FORMAT_BGRA1010102,
+       DRM_FORMAT_YUYV,
+       DRM_FORMAT_YVYU,
+       DRM_FORMAT_UYVY,
+       DRM_FORMAT_VYUY,
+       DRM_FORMAT_AYUV,
+       DRM_FORMAT_NV12,
+       DRM_FORMAT_NV21,
+       DRM_FORMAT_NV16,
+       DRM_FORMAT_NV61,
+       DRM_FORMAT_NV24,
+       DRM_FORMAT_NV42,
+       DRM_FORMAT_YUV410,
+       DRM_FORMAT_YVU410,
+       DRM_FORMAT_YUV411,
+       DRM_FORMAT_YVU411,
+       DRM_FORMAT_YUV420,
+       DRM_FORMAT_YVU420,
+       DRM_FORMAT_YUV422,
+       DRM_FORMAT_YVU422,
+       DRM_FORMAT_YUV444,
+       DRM_FORMAT_YVU444,
+};
+
 /**
  * drm_bridge_funcs - drm_bridge control functions
  * @mode_fixup: Try to fixup (or reject entirely) proposed mode for this bridge
-- 
1.8.5.1