NoGUI: Use current resolution if unspecified

src/common/drm_display.cpp

@@ -1,6 +1,7 @@
 #include "drm_display.h"
 #include "common/assert.h"
 #include "common/log.h"
+#include "common/scope_guard.h"
 #include "common/string.h"
 #include "file_system.h"
 #include <cmath>
@@ -9,6 +10,11 @@
 #include <unistd.h>
 Log_SetChannel(DRMDisplay);
 
+enum
+{
+  MAX_CARDS_TO_TRY = 10
+};
+
 DRMDisplay::DRMDisplay(int card /*= 1*/) : m_card_id(card) {}
 
 DRMDisplay::~DRMDisplay()
@@ -72,7 +78,7 @@ bool DRMDisplay::Initialize(u32 width, u32 height, float refresh_rate)
 {
   if (m_card_id < 0)
   {
-    for (int i = 0; i < 10; i++)
+    for (int i = 0; i < MAX_CARDS_TO_TRY; i++)
     {
       if (TryOpeningCard(i, width, height, refresh_rate))
         return true;
@@ -265,3 +271,101 @@ void DRMDisplay::PresentBuffer(u32 fb_id, bool wait_for_vsync)
     drmHandleEvent(m_card_fd, &event_ctx);
   }
 }
+
+bool DRMDisplay::GetCurrentMode(u32* width, u32* height, float* refresh_rate, int card, int connector)
+{
+  int card_fd = -1;
+  if (card < 0)
+  {
+    for (int try_card = 0; try_card < MAX_CARDS_TO_TRY; try_card++)
+    {
+      card_fd = open(TinyString::FromFormat("/dev/dri/card%d", try_card), O_RDWR);
+      if (card_fd >= 0)
+        break;
+    }
+  }
+  else
+  {
+    card_fd = open(TinyString::FromFormat("/dev/dri/card%d", card), O_RDWR);
+  }
+
+  if (card_fd < 0)
+  {
+    Log_ErrorPrintf("open(/dev/dri/card%d) failed: %d (%s)", card, errno, strerror(errno));
+    return false;
+  }
+
+  Common::ScopeGuard card_guard([card_fd]() { close(card_fd); });
+
+  drmModeRes* resources = drmModeGetResources(card_fd);
+  if (!resources)
+  {
+    Log_ErrorPrintf("drmModeGetResources() failed: %d (%s)", errno, strerror(errno));
+    return false;
+  }
+
+  Common::ScopeGuard resources_guard([resources]() { drmModeFreeResources(resources); });
+  drmModeConnector* connector_ptr = nullptr;
+  if (connector < 0)
+  {
+    for (int i = 0; i < resources->count_connectors; i++)
+    {
+      connector_ptr = drmModeGetConnector(card_fd, resources->connectors[i]);
+      if (connector_ptr->connection == DRM_MODE_CONNECTED)
+        break;
+
+      drmModeFreeConnector(connector_ptr);
+    }
+  }
+  else if (connector < resources->count_connectors)
+  {
+    connector_ptr = drmModeGetConnector(card_fd, resources->connectors[connector]);
+  }
+
+  Common::ScopeGuard connector_guard([connector_ptr]() {
+    if (connector_ptr)
+      drmModeFreeConnector(connector_ptr);
+  });
+  if (!connector_ptr || connector_ptr->connection != DRM_MODE_CONNECTED)
+  {
+    Log_ErrorPrintf("No connector found");
+    return false;
+  }
+
+  drmModeEncoder* encoder = drmModeGetEncoder(card_fd, connector_ptr->encoder_id);
+  if (!encoder)
+  {
+    Log_ErrorPrint("No encoder found");
+    return false;
+  }
+
+  Common::ScopeGuard encoder_guard([encoder]() { drmModeFreeEncoder(encoder); });
+
+  drmModeCrtc* crtc = drmModeGetCrtc(card_fd, encoder->crtc_id);
+  if (!crtc)
+  {
+    Log_ErrorPrint("No CRTC found");
+    return false;
+  }
+
+  if (!crtc->mode_valid)
+  {
+    Log_ErrorPrint("CRTC mode not valid");
+    return false;
+  }
+
+  const u32 current_width = static_cast<u32>(crtc->mode.hdisplay);
+  const u32 current_height = static_cast<u32>(crtc->mode.vdisplay);
+  const float current_refresh_rate = (static_cast<float>(crtc->mode.clock) * 1000.0f) /
+                                     (static_cast<float>(crtc->mode.htotal) * static_cast<float>(crtc->mode.vtotal));
+  Log_InfoPrintf("Current mode for card %d: %ux%u@%f", card, current_width, current_height, current_refresh_rate);
+
+  if (width)
+    *width = current_width;
+  if (height)
+    *height = current_height;
+  if (refresh_rate)
+    *refresh_rate = current_refresh_rate;
+
+  return true;
+}

src/common/drm_display.h

@@ -11,6 +11,8 @@ public:
   DRMDisplay(int card = -1);
   ~DRMDisplay();
 
+  static bool GetCurrentMode(u32* width, u32* height, float* refresh_rate, int card = -1, int connector = -1);
+
   bool Initialize(u32 width, u32 height, float refresh_rate);
 
   int GetCardID() const { return m_card_id; }

src/duckstation-nogui/CMakeLists.txt

@@ -29,6 +29,10 @@ if(USE_EVDEV)
   target_link_libraries(duckstation-nogui PRIVATE ${LIBEVDEV_LIBRARIES})
 endif()
 
+if(USE_DRMKMS)
+  target_compile_definitions(duckstation-nogui PRIVATE "-DWITH_DRMKMS=1")
+endif()
+
 if(WIN32)
   target_sources(duckstation-nogui PRIVATE
     duckstation-nogui.manifest

src/duckstation-nogui/nogui_host_interface.cpp

@@ -125,6 +125,7 @@ bool NoGUIHostInterface::CreateDisplay()
   if (!CreateHostDisplayResources())
     Log_WarningPrint("Failed to create host display resources");
 
+  Log_InfoPrintf("Host display initialized at %ux%u resolution", m_display->GetWindowWidth(), m_display->GetWindowHeight());
   return true;
 }
 

src/duckstation-nogui/vty_host_interface.cpp

@@ -10,6 +10,10 @@
 #include <unistd.h>
 Log_SetChannel(VTYHostInterface);
 
+#ifdef WITH_DRMKMS
+#include "common/drm_display.h"
+#endif
+
 VTYHostInterface::VTYHostInterface() = default;
 
 VTYHostInterface::~VTYHostInterface()
@@ -88,6 +92,15 @@ std::optional<WindowInfo> VTYHostInterface::GetPlatformWindowInfo()
     }
   }
 
+#ifdef WITH_DRMKMS
+  // set to current mode
+  if (wi.surface_width == 0)
+  {
+    if (!DRMDisplay::GetCurrentMode(&wi.surface_width, &wi.surface_height, &wi.surface_refresh_rate))
+      Log_ErrorPrintf("Failed to get current mode, will use default.");
+  }
+#endif
+
   return wi;
 }