System: Add "Disable Mailbox Presentation" option

Partial backport of https://github.com/PCSX2/pcsx2/pull/11296

src/core/fullscreen_ui.cpp

@@ -4283,6 +4283,12 @@ void FullscreenUI::DrawDisplaySettingsPage()
       break;
   }
 
+  DrawToggleSetting(
+    bsi, FSUI_CSTR("Disable Mailbox Presentation"),
+    FSUI_CSTR("Forces the use of FIFO over Mailbox presentation, i.e. double buffering instead of triple buffering. "
+              "Usually results in worse frame pacing."),
+    "Display", "DisableMailboxPresentation", false);
+
   if (renderer != GPURenderer::Software)
   {
     DrawToggleSetting(
@@ -7296,13 +7302,13 @@ TRANSLATE_NOOP("FullscreenUI", "Determines which algorithm is used to convert in
 TRANSLATE_NOOP("FullscreenUI", "Device Settings");
 TRANSLATE_NOOP("FullscreenUI", "Disable All Enhancements");
 TRANSLATE_NOOP("FullscreenUI", "Disable Interlacing");
+TRANSLATE_NOOP("FullscreenUI", "Disable Mailbox Presentation");
 TRANSLATE_NOOP("FullscreenUI", "Disable Subdirectory Scanning");
 TRANSLATE_NOOP("FullscreenUI", "Disabled");
 TRANSLATE_NOOP("FullscreenUI", "Disables dithering and uses the full 8 bits per channel of color information.");
 TRANSLATE_NOOP("FullscreenUI", "Disables interlaced rendering and display in the GPU. Some games can render in 480p this way, but others will break.");
 TRANSLATE_NOOP("FullscreenUI", "Disc {} | {}");
 TRANSLATE_NOOP("FullscreenUI", "Discord Server");
-TRANSLATE_NOOP("FullscreenUI", "Display FPS Limit");
 TRANSLATE_NOOP("FullscreenUI", "Display Settings");
 TRANSLATE_NOOP("FullscreenUI", "Displays popup messages on events such as achievement unlocks and leaderboard submissions.");
 TRANSLATE_NOOP("FullscreenUI", "Displays popup messages when starting, submitting, or failing a leaderboard challenge.");
@@ -7371,6 +7377,7 @@ TRANSLATE_NOOP("FullscreenUI", "Force 4:3 For 24-Bit Display");
 TRANSLATE_NOOP("FullscreenUI", "Force NTSC Timings");
 TRANSLATE_NOOP("FullscreenUI", "Forces PAL games to run at NTSC timings, i.e. 60hz. Some PAL games will run at their \"normal\" speeds, while others will break.");
 TRANSLATE_NOOP("FullscreenUI", "Forces a full rescan of all games previously identified.");
+TRANSLATE_NOOP("FullscreenUI", "Forces the use of FIFO over Mailbox presentation, i.e. double buffering instead of triple buffering. Usually results in worse frame pacing.");
 TRANSLATE_NOOP("FullscreenUI", "Forcibly mutes both CD-DA and XA audio from the CD-ROM. Can be used to disable background music in some games.");
 TRANSLATE_NOOP("FullscreenUI", "Frame Time Buffer");
 TRANSLATE_NOOP("FullscreenUI", "From File...");
@@ -7429,7 +7436,6 @@ TRANSLATE_NOOP("FullscreenUI", "Launch a game from images scanned from your game
 TRANSLATE_NOOP("FullscreenUI", "Leaderboard Notifications");
 TRANSLATE_NOOP("FullscreenUI", "Leaderboards");
 TRANSLATE_NOOP("FullscreenUI", "Leaderboards are not enabled.");
-TRANSLATE_NOOP("FullscreenUI", "Limits how many frames are displayed to the screen. These frames are still rendered.");
 TRANSLATE_NOOP("FullscreenUI", "Line Detection");
 TRANSLATE_NOOP("FullscreenUI", "List Settings");
 TRANSLATE_NOOP("FullscreenUI", "Load Devices From Save States");

src/core/fullscreen_ui.h

@@ -1,4 +1,5 @@
 // SPDX-FileCopyrightText: 2019-2023 Connor McLaughlin <stenzek@gmail.com>
+// SPDX-FileCopyrightText: 2019-2023 Connor McLaughlin <stenzek@gmail.com>
 // SPDX-License-Identifier: (GPL-3.0 OR CC-BY-NC-ND-4.0)
 
 #pragma once

src/core/settings.cpp

@@ -277,6 +277,7 @@ void Settings::Load(SettingsInterface& si)
     si.GetFloatValue("Display", "PreFrameSleepBuffer", DEFAULT_DISPLAY_PRE_FRAME_SLEEP_BUFFER);
   display_skip_presenting_duplicate_frames = si.GetBoolValue("Display", "SkipPresentingDuplicateFrames", false);
   display_vsync = si.GetBoolValue("Display", "VSync", false);
+  display_disable_mailbox_presentation = si.GetBoolValue("Display", "DisableMailboxPresentation", false);
   display_force_4_3_for_24bit = si.GetBoolValue("Display", "Force4_3For24Bit", false);
   display_active_start_offset = static_cast<s16>(si.GetIntValue("Display", "ActiveStartOffset", 0));
   display_active_end_offset = static_cast<s16>(si.GetIntValue("Display", "ActiveEndOffset", 0));
@@ -529,6 +530,7 @@ void Settings::Save(SettingsInterface& si, bool ignore_base) const
   si.SetBoolValue("Display", "SkipPresentingDuplicateFrames", display_skip_presenting_duplicate_frames);
   si.SetFloatValue("Display", "PreFrameSleepBuffer", display_pre_frame_sleep_buffer);
   si.SetBoolValue("Display", "VSync", display_vsync);
+  si.SetBoolValue("Display", "DisableMailboxPresentation", display_disable_mailbox_presentation);
   si.SetStringValue("Display", "ExclusiveFullscreenControl",
                     GetDisplayExclusiveFullscreenControlName(display_exclusive_fullscreen_control));
   si.SetStringValue("Display", "ScreenshotMode", GetDisplayScreenshotModeName(display_screenshot_mode));

src/core/settings.h

@@ -152,6 +152,7 @@ struct Settings
   bool display_pre_frame_sleep : 1 = false;
   bool display_skip_presenting_duplicate_frames : 1 = false;
   bool display_vsync : 1 = false;
+  bool display_disable_mailbox_presentation : 1 = true;
   bool display_force_4_3_for_24bit : 1 = false;
   bool gpu_24bit_chroma_smoothing : 1 = false;
   bool display_show_osd_messages : 1 = true;

src/core/system.cpp

@@ -2962,8 +2962,11 @@ GPUVSyncMode System::GetEffectiveVSyncMode()
   // If there's no VM, or we're using vsync for timing, then we always use double-buffered (blocking).
   // Try to keep the same present mode whether we're running or not, since it'll avoid flicker.
   const bool valid_vm = (s_state != State::Shutdown && s_state != State::Stopping);
-  if (s_can_sync_to_host || (!valid_vm && g_settings.sync_to_host_refresh_rate))
+  if (s_can_sync_to_host || (!valid_vm && g_settings.sync_to_host_refresh_rate) ||
+      g_settings.display_disable_mailbox_presentation)
+  {
     return GPUVSyncMode::FIFO;
+  }
 
   // For PAL games, we always want to triple buffer, because otherwise we'll be tearing.
   // Or for when we aren't using sync-to-host-refresh, to avoid dropping frames.
@@ -4054,6 +4057,7 @@ void System::CheckForSettingsChanges(const Settings& old_settings)
         g_settings.display_pre_frame_sleep != old_settings.display_pre_frame_sleep ||
         g_settings.display_pre_frame_sleep_buffer != old_settings.display_pre_frame_sleep_buffer ||
         g_settings.display_vsync != old_settings.display_vsync ||
+        g_settings.display_disable_mailbox_presentation != old_settings.display_disable_mailbox_presentation ||
         g_settings.sync_to_host_refresh_rate != old_settings.sync_to_host_refresh_rate)
     {
       UpdateSpeedLimiterState();
@@ -4073,8 +4077,11 @@ void System::CheckForSettingsChanges(const Settings& old_settings)
   {
     if (g_gpu_device)
     {
-      if (g_settings.display_vsync != old_settings.display_vsync)
+      if (g_settings.display_vsync != old_settings.display_vsync ||
+          g_settings.display_disable_mailbox_presentation != old_settings.display_disable_mailbox_presentation)
+      {
         UpdateDisplayVSync();
+      }
     }
   }