drm: check syncobj timeline support before advertising protocol

src/Compositor.cpp

@@ -73,6 +73,7 @@
 #include <sys/resource.h>
 #include <malloc.h>
 #include <unistd.h>
+#include <xf86drm.h>
 
 using namespace Hyprutils::String;
 using namespace Aquamarine;
@@ -167,6 +168,10 @@ void CCompositor::restoreNofile() {
         Debug::log(ERR, "Failed restoring NOFILE limits");
 }
 
+bool CCompositor::supportsDrmSyncobjTimeline() const {
+    return m_bDrmSyncobjTimelineSupported;
+}
+
 void CCompositor::setMallocThreshold() {
 #ifdef M_TRIM_THRESHOLD
     // The default is 128 pages,
@@ -354,6 +359,16 @@ void CCompositor::initServer(std::string socketName, int socketFd) {
     m_drmFD = m_aqBackend->drmFD();
     Debug::log(LOG, "Running on DRMFD: {}", m_drmFD);
 
+    if (m_drmFD >= 0) {
+        uint64_t cap                   = 0;
+        int      ret                   = drmGetCap(m_drmFD, DRM_CAP_SYNCOBJ_TIMELINE, &cap);
+        m_bDrmSyncobjTimelineSupported = (ret == 0 && cap != 0);
+        Debug::log(LOG, "DRM syncobj timeline support: {}", m_bDrmSyncobjTimelineSupported ? "yes" : "no");
+    } else {
+        m_bDrmSyncobjTimelineSupported = false;
+        Debug::log(LOG, "DRM syncobj timeline support: no (no DRM FD)");
+    }
+
     if (!socketName.empty() && socketFd != -1) {
         fcntl(socketFd, F_SETFD, FD_CLOEXEC);
         const auto RETVAL = wl_display_add_socket_fd(m_wlDisplay, socketFd);

src/Compositor.hpp

@@ -152,6 +152,7 @@ class CCompositor {
     NColorManagement::SImageDescription getPreferredImageDescription();
     bool                                shouldChangePreferredImageDescription();
 
+    bool                                supportsDrmSyncobjTimeline() const;
     std::string                         m_explicitConfigPath;
 
   private:
@@ -165,6 +166,8 @@ class CCompositor {
     void             removeLockFile();
     void             setMallocThreshold();
 
+    bool             m_bDrmSyncobjTimelineSupported = false;
+
     uint64_t         m_hyprlandPID    = 0;
     wl_event_source* m_critSigSource  = nullptr;
     rlimit           m_originalNofile = {};

src/helpers/sync/SyncTimeline.cpp

@@ -1,12 +1,16 @@
 #include "SyncTimeline.hpp"
 #include "../../defines.hpp"
 #include "../../managers/eventLoop/EventLoopManager.hpp"
+#include "../../Compositor.hpp"
 
 #include <xf86drm.h>
 #include <sys/eventfd.h>
 using namespace Hyprutils::OS;
 
 SP<CSyncTimeline> CSyncTimeline::create(int drmFD_) {
+    if (!g_pCompositor->supportsDrmSyncobjTimeline())
+        return nullptr;
+
     auto timeline     = SP<CSyncTimeline>(new CSyncTimeline);
     timeline->m_drmFD = drmFD_;
     timeline->m_self  = timeline;
@@ -20,6 +24,9 @@ SP<CSyncTimeline> CSyncTimeline::create(int drmFD_) {
 }
 
 SP<CSyncTimeline> CSyncTimeline::create(int drmFD_, CFileDescriptor&& drmSyncobjFD) {
+    if (!g_pCompositor->supportsDrmSyncobjTimeline())
+        return nullptr;
+
     auto timeline         = SP<CSyncTimeline>(new CSyncTimeline);
     timeline->m_drmFD     = drmFD_;
     timeline->m_syncobjFD = std::move(drmSyncobjFD);

src/managers/ProtocolManager.cpp

@@ -70,6 +70,7 @@
 #include "content-type-v1.hpp"
 
 #include <aquamarine/buffer/Buffer.hpp>
+#include <xf86drm.h>
 #include <aquamarine/backend/Backend.hpp>
 #include <hyprutils/memory/UniquePtr.hpp>
 
@@ -210,8 +211,13 @@ CProtocolManager::CProtocolManager() {
         else
             lease.reset();
 
-        if (g_pHyprOpenGL->m_exts.EGL_ANDROID_native_fence_sync_ext && !PROTO::sync)
-            PROTO::sync = makeUnique<CDRMSyncobjProtocol>(&wp_linux_drm_syncobj_manager_v1_interface, 1, "DRMSyncobj");
+        if (g_pHyprOpenGL->m_exts.EGL_ANDROID_native_fence_sync_ext && !PROTO::sync) {
+            if (g_pCompositor->supportsDrmSyncobjTimeline()) {
+                PROTO::sync = makeUnique<CDRMSyncobjProtocol>(&wp_linux_drm_syncobj_manager_v1_interface, 1, "DRMSyncobj");
+                Debug::log(LOG, "DRM Syncobj Timeline support detected, enabling explicit sync protocol");
+            } else
+                Debug::log(WARN, "DRM Syncobj Timeline not supported, skipping explicit sync protocol");
+        }
     }
 
     if (!g_pHyprOpenGL->getDRMFormats().empty()) {