NVDEC (H264): Use separate contexts per channel and decode frames in DTS order (#2671)

* Use separate NVDEC contexts per channel (for FFMPEG)

* Remove NVDEC -> VIC frame override hack

* Add missing bottom_field_pic_order_in_frame_present_flag

* Make FFMPEG logging static

* nit: Remove empty lines

* New FFMPEG decoding approach -- call h264_decode_frame directly, trim surface cache to reduce memory usage

* Fix case

* Silence warnings

* PR feedback

* Per-decoder rather than per-codec ownership of surfaces on the cache

2 files changed, 103 insertions, 11 deletions

diff --git a/Ryujinx.Graphics.Host1x/Host1xDevice.cs b/Ryujinx.Graphics.Host1x/Host1xDevice.cs
index 7f6cef62..61408fc4 100644
--- a/Ryujinx.Graphics.Host1x/Host1xDevice.cs
+++ b/Ryujinx.Graphics.Host1x/Host1xDevice.cs
@@ -9,8 +9,20 @@ namespace Ryujinx.Graphics.Host1x
 {
     public sealed class Host1xDevice : IDisposable
     {
+        private struct Command
+        {
+            public int[] Buffer { get; }
+            public long ContextId { get; }
+
+            public Command(int[] buffer, long contextId)
+            {
+                Buffer = buffer;
+                ContextId = contextId;
+            }
+        }
+
         private readonly SyncptIncrManager _syncptIncrMgr;
-        private readonly AsyncWorkQueue<int[]> _commandQueue;
+        private readonly AsyncWorkQueue<Command> _commandQueue;
 
         private readonly Devices _devices = new Devices();
 
@@ -26,7 +38,7 @@ namespace Ryujinx.Graphics.Host1x
         public Host1xDevice(SynchronizationManager syncMgr)
         {
             _syncptIncrMgr = new SyncptIncrManager(syncMgr);
-            _commandQueue = new AsyncWorkQueue<int[]>(Process, "Ryujinx.Host1xProcessor");
+            _commandQueue = new AsyncWorkQueue<Command>(Process, "Ryujinx.Host1xProcessor");
 
             Class = new Host1xClass(syncMgr);
 
@@ -39,13 +51,52 @@ namespace Ryujinx.Graphics.Host1x
             _devices.RegisterDevice(classId, thi);
         }
 
-        public void Submit(ReadOnlySpan<int> commandBuffer)
+        public long CreateContext()
         {
-            _commandQueue.Add(commandBuffer.ToArray());
+            if (_devices.GetDevice(ClassId.Nvdec) is IDeviceStateWithContext nvdec)
+            {
+                return nvdec.CreateContext();
+            }
+
+            return -1;
         }
 
-        private void Process(int[] commandBuffer)
+        public void DestroyContext(long id)
         {
+            if (id == -1)
+            {
+                return;
+            }
+
+            if (_devices.GetDevice(ClassId.Nvdec) is IDeviceStateWithContext nvdec)
+            {
+                nvdec.DestroyContext(id);
+            }
+        }
+
+        private void SetNvdecContext(long id)
+        {
+            if (id == -1)
+            {
+                return;
+            }
+
+            if (_devices.GetDevice(ClassId.Nvdec) is IDeviceStateWithContext nvdec)
+            {
+                nvdec.BindContext(id);
+            }
+        }
+
+        public void Submit(ReadOnlySpan<int> commandBuffer, long contextId)
+        {
+            _commandQueue.Add(new Command(commandBuffer.ToArray(), contextId));
+        }
+
+        private void Process(Command command)
+        {
+            SetNvdecContext(command.ContextId);
+            int[] commandBuffer = command.Buffer;
+
             for (int index = 0; index < commandBuffer.Length; index++)
             {
                 Step(commandBuffer[index]);
diff --git a/Ryujinx.Graphics.Host1x/ThiDevice.cs b/Ryujinx.Graphics.Host1x/ThiDevice.cs
index 8e3e11b0..114ee26e 100644
--- a/Ryujinx.Graphics.Host1x/ThiDevice.cs
+++ b/Ryujinx.Graphics.Host1x/ThiDevice.cs
@@ -5,19 +5,24 @@ using System.Collections.Generic;
 
 namespace Ryujinx.Graphics.Host1x
 {
-    class ThiDevice : IDeviceState, IDisposable
+    class ThiDevice : IDeviceStateWithContext, IDisposable
     {
         private readonly ClassId _classId;
         private readonly IDeviceState _device;
 
         private readonly SyncptIncrManager _syncptIncrMgr;
 
+        private long _currentContextId;
+        private long _previousContextId;
+
         private class CommandAction
         {
+            public long ContextId { get; }
             public int Data { get; }
 
-            public CommandAction(int data)
+            public CommandAction(long contextId, int data)
             {
+                ContextId = contextId;
                 Data = data;
             }
         }
@@ -26,7 +31,7 @@ namespace Ryujinx.Graphics.Host1x
         {
             public int Method { get; }
 
-            public MethodCallAction(int method, int data) : base(data)
+            public MethodCallAction(long contextId, int method, int data) : base(contextId, data)
             {
                 Method = method;
             }
@@ -34,7 +39,7 @@ namespace Ryujinx.Graphics.Host1x
 
         private class SyncptIncrAction : CommandAction
         {
-            public SyncptIncrAction(uint syncptIncrHandle) : base((int)syncptIncrHandle)
+            public SyncptIncrAction(long contextId, uint syncptIncrHandle) : base(contextId, (int)syncptIncrHandle)
             {
             }
         }
@@ -54,6 +59,31 @@ namespace Ryujinx.Graphics.Host1x
                 { nameof(ThiRegisters.IncrSyncpt), new RwCallback(IncrSyncpt, null) },
                 { nameof(ThiRegisters.Method1), new RwCallback(Method1, null) }
             });
+
+            _previousContextId = -1;
+        }
+
+        public long CreateContext()
+        {
+            if (_device is IDeviceStateWithContext deviceWithContext)
+            {
+                return deviceWithContext.CreateContext();
+            }
+
+            return -1;
+        }
+
+        public void DestroyContext(long id)
+        {
+            if (_device is IDeviceStateWithContext deviceWithContext)
+            {
+                deviceWithContext.DestroyContext(id);
+            }
+        }
+
+        public void BindContext(long id)
+        {
+            _currentContextId = id;
         }
 
         public int Read(int offset) => _state.Read(offset);
@@ -70,17 +100,28 @@ namespace Ryujinx.Graphics.Host1x
             }
             else
             {
-                _commandQueue.Add(new SyncptIncrAction(_syncptIncrMgr.IncrementWhenDone(_classId, syncpointId)));
+                _commandQueue.Add(new SyncptIncrAction(_currentContextId, _syncptIncrMgr.IncrementWhenDone(_classId, syncpointId)));
             }
         }
 
         private void Method1(int data)
         {
-            _commandQueue.Add(new MethodCallAction((int)_state.State.Method0 * 4, data));
+            _commandQueue.Add(new MethodCallAction(_currentContextId, (int)_state.State.Method0 * 4, data));
         }
 
         private void Process(CommandAction cmdAction)
         {
+            long contextId = cmdAction.ContextId;
+            if (contextId != _previousContextId)
+            {
+                _previousContextId = contextId;
+
+                if (_device is IDeviceStateWithContext deviceWithContext)
+                {
+                    deviceWithContext.BindContext(contextId);
+                }
+            }
+
             if (cmdAction is SyncptIncrAction syncptIncrAction)
             {
                 _syncptIncrMgr.SignalDone((uint)syncptIncrAction.Data);