c/main: Be even more paranoid about display timing code

src/xrt/compositor/main/comp_target.h

@@ -32,6 +32,15 @@ enum comp_target_timing_point
 	COMP_TARGET_TIMING_POINT_SUBMIT,  //<! Submitted work to the GPU.
 };
 
+/*!
+ * If the target should use the display timing information.
+ */
+enum comp_target_display_timing_usage
+{
+	COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING = 0,
+	COMP_TARGET_USE_DISPLAY_IF_AVAILABLE = 1,
+};
+
 /*!
  * Image and view pair for @ref comp_target.
  *
@@ -218,8 +227,13 @@ comp_target_create_images(struct comp_target *ct,
 {
 	COMP_TRACE_MARKER();
 
-	ct->create_images(ct, preferred_width, preferred_height, preferred_color_format, preferred_color_space,
+	ct->create_images(          //
-	                  present_mode);
+	    ct,                     //
+	    preferred_width,        //
+	    preferred_height,       //
+	    preferred_color_format, //
+	    preferred_color_space,  //
+	    present_mode);          //
 }
 
 /*!

src/xrt/compositor/main/comp_target_swapchain.c

@@ -95,16 +95,13 @@ comp_target_swapchain_create_images(struct comp_target *ct,
 	VkBool32 supported;
 	VkResult ret;
 
-#ifndef XRT_OS_ANDROID
+	// Some platforms really don't like the display_timing code.
-	if (cts->uft == NULL && vk->has_GOOGLE_display_timing) {
+	bool use_display_timing_if_available = cts->timing_usage == COMP_TARGET_USE_DISPLAY_IF_AVAILABLE;
+	if (cts->uft == NULL && use_display_timing_if_available && vk->has_GOOGLE_display_timing) {
 		u_frame_timing_display_timing_create(ct->c->settings.nominal_frame_interval_ns, &cts->uft);
 	} else if (cts->uft == NULL) {
 		u_frame_timing_fake_create(ct->c->settings.nominal_frame_interval_ns, &cts->uft);
 	}
-#else
-	COMP_INFO(ct->c, "Always using the fake timing code on Android.");
-	u_frame_timing_fake_create(ct->c->settings.nominal_frame_interval_ns, &cts->uft);
-#endif
 
 	// Free old image views.
 	comp_target_swapchain_destroy_image_views(cts);
@@ -645,8 +642,10 @@ comp_target_swapchain_cleanup(struct comp_target_swapchain *cts)
 }
 
 void
-comp_target_swapchain_init_set_fnptrs(struct comp_target_swapchain *cts)
+comp_target_swapchain_init_and_set_fnptrs(struct comp_target_swapchain *cts,
+                                          enum comp_target_display_timing_usage timing_usage)
 {
+	cts->timing_usage = timing_usage;
 	cts->base.create_images = comp_target_swapchain_create_images;
 	cts->base.acquire = comp_target_swapchain_acquire_next_image;
 	cts->base.present = comp_target_swapchain_present;

src/xrt/compositor/main/comp_target_swapchain.h

@@ -41,6 +41,9 @@ struct comp_target_swapchain
 	//! Frame timing tracker.
 	struct u_frame_timing *uft;
 
+	//! If we should use display timing.
+	enum comp_target_display_timing_usage timing_usage;
+
 	//! Also works as a frame index.
 	int64_t current_frame_id;
 
@@ -78,7 +81,8 @@ struct comp_target_swapchain
  * @ingroup comp_main
  */
 void
-comp_target_swapchain_init_set_fnptrs(struct comp_target_swapchain *cts);
+comp_target_swapchain_init_and_set_fnptrs(struct comp_target_swapchain *cts,
+                                          enum comp_target_display_timing_usage timing_usage);
 
 /*!
  * Free all managed resources on the given @ref comp_target_swapchain,

src/xrt/compositor/main/comp_window_android.c

@@ -167,7 +167,8 @@ comp_window_android_create(struct comp_compositor *c)
 {
 	struct comp_window_android *w = U_TYPED_CALLOC(struct comp_window_android);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	// The display timing code hasn't been tested on Android and may be broken.
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING);
 
 	w->base.base.name = "Android";
 	w->base.base.destroy = comp_window_android_destroy;

src/xrt/compositor/main/comp_window_direct_nvidia.c

@@ -86,7 +86,8 @@ comp_window_direct_nvidia_create(struct comp_compositor *c)
 {
 	struct comp_window_direct_nvidia *w = U_TYPED_CALLOC(struct comp_window_direct_nvidia);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	// The display timing code hasn't been tested on nVidia and may be broken.
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING);
 
 	w->base.base.name = "direct";
 	w->base.base.destroy = comp_window_direct_nvidia_destroy;

src/xrt/compositor/main/comp_window_direct_randr.c

@@ -113,7 +113,8 @@ comp_window_direct_randr_create(struct comp_compositor *c)
 {
 	struct comp_window_direct_randr *w = U_TYPED_CALLOC(struct comp_window_direct_randr);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	// Display timing is tested and know working.
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_USE_DISPLAY_IF_AVAILABLE);
 
 	w->base.base.name = "direct";
 	w->base.base.destroy = comp_window_direct_randr_destroy;

src/xrt/compositor/main/comp_window_mswin.c

@@ -189,7 +189,8 @@ comp_window_mswin_create(struct comp_compositor *c)
 {
 	struct comp_window_mswin *w = U_TYPED_CALLOC(struct comp_window_mswin);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	// The display timing code hasn't been tested on Windows and may be broken.
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING);
 
 	w->base.base.name = "MS Windows";
 	w->base.base.destroy = comp_window_mswin_destroy;

src/xrt/compositor/main/comp_window_vk_display.c

@@ -84,7 +84,8 @@ comp_window_vk_display_create(struct comp_compositor *c)
 {
 	struct comp_window_vk_display *w = U_TYPED_CALLOC(struct comp_window_vk_display);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	// The display timing code hasn't been tested on vk display and may be broken.
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING);
 
 	w->base.base.name = "VkDisplayKHR";
 	w->base.base.destroy = comp_window_vk_display_destroy;

src/xrt/compositor/main/comp_window_wayland.c

@@ -102,7 +102,8 @@ comp_window_wayland_create(struct comp_compositor *c)
 {
 	struct comp_window_wayland *w = U_TYPED_CALLOC(struct comp_window_wayland);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	// The display timing code hasn't been tested on Wayland and may be broken.
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING);
 
 	w->base.base.name = "wayland";
 	w->base.base.destroy = comp_window_wayland_destroy;

src/xrt/compositor/main/comp_window_xcb.c

@@ -128,7 +128,11 @@ comp_window_xcb_create(struct comp_compositor *c)
 {
 	struct comp_window_xcb *w = U_TYPED_CALLOC(struct comp_window_xcb);
 
-	comp_target_swapchain_init_set_fnptrs(&w->base);
+	/*
+	 * The display timing code has been tested on XCB,
+	 * and is know to be broken when using VK_PRESENT_MODE_IMMEDIATE_KHR.
+	 */
+	comp_target_swapchain_init_and_set_fnptrs(&w->base, COMP_TARGET_FORCE_FAKE_DISPLAY_TIMING);
 
 	w->base.base.name = "xcb";
 	w->base.base.destroy = comp_window_xcb_destroy;