From c0506bcf5d85362d9505356c1a5fb1a2999cb34b Mon Sep 17 00:00:00 2001
From: "yuri.benditovich@daynix.com" <yuri.benditovich@daynix.com>
Date: Wed, 22 Feb 2017 15:38:49 +0200
Subject: [PATCH] qxl-wddm-dod: Preparation for VSync activation

Prepare all the procedures needed for VSync feature but
do not turn it on yet. Manual uncomment still required to
enable it.
Advanced users may enable VSync feature and report functional
problem with it. The driver is expected to pass all the formal
tests under HLK 1607 with device rev.3 and rev.4 but with
device rev.4 on setups with high load or long round-trip delay
video system may detect timeout during rendering operation
and disable the driver with error 43.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Acked-by: Frediano Ziglio <fziglio@redhat.com>
---
 qxldod/driver.cpp | 64 +++++++++++++++++++++++++++++++++++++++++++++++
 qxldod/driver.h   | 15 +++++++++++
 2 files changed, 79 insertions(+)

diff --git a/qxldod/driver.cpp b/qxldod/driver.cpp
index dc84aa8..1946147 100755
--- a/qxldod/driver.cpp
+++ b/qxldod/driver.cpp
@@ -32,6 +32,31 @@ DriverEntry(
 
     DbgPrint(TRACE_LEVEL_FATAL, ("---> KMDOD build on on %s %s\n", __DATE__, __TIME__));
 
+    RTL_OSVERSIONINFOW versionInfo;
+    versionInfo.dwOSVersionInfoSize = sizeof(versionInfo);
+
+    RtlGetVersion(&versionInfo);
+
+    // VSync control is NOT planned to be enabled on Win10 builds
+    // before RS1. Enabling it on DOD driver causes OS to stop the driver
+    // with error 43 when the system turns off display due to idle setting.
+    // On Windows 8.1 (9200 and 9600) till now no problem observed
+    // (OS does not send VSync enable command)
+    // On Windows 10RS1 (14393) enabling VSync control activates
+    // watchdog policy and creates high sensitivity to long (> 2 sec)
+    // processing in PresentDisplayOnly callback (stop with error 43)
+
+    if (versionInfo.dwBuildNumber >= 14393 || versionInfo.dwBuildNumber <= 9600)
+    {
+        // we will uncomment the line below after we address all the problems
+        // related to enabled VSync control in Win10RS1
+
+        //g_bSupportVSync = TRUE;
+    }
+    DbgPrint(TRACE_LEVEL_WARNING, ("VSync support %sabled for %d.%d.%d\n",
+        g_bSupportVSync ? "en" : "dis",
+        versionInfo.dwMajorVersion, versionInfo.dwMinorVersion, versionInfo.dwBuildNumber));
+
     // Initialize DDI function pointers and dxgkrnl
     KMDDOD_INITIALIZATION_DATA InitialData = {0};
 
@@ -67,6 +92,11 @@ DriverEntry(
     InitialData.DxgkDdiStopDeviceAndReleasePostDisplayOwnership = DodStopDeviceAndReleasePostDisplayOwnership;
     InitialData.DxgkDdiSystemDisplayEnable          = DodSystemDisplayEnable;
     InitialData.DxgkDdiSystemDisplayWrite           = DodSystemDisplayWrite;
+    if (g_bSupportVSync)
+    {
+        InitialData.DxgkDdiControlInterrupt = DodControlInterrupt;
+        InitialData.DxgkDdiGetScanLine = DodGetScanLine;
+    }
 
     NTSTATUS Status = DxgkInitializeDisplayOnlyDriver(pDriverObject, pRegistryPath, &InitialData);
     if (!NT_SUCCESS(Status))
@@ -559,6 +589,40 @@ DodQueryVidPnHWCapability(
     return pQxl->QueryVidPnHWCapability(pVidPnHWCaps);
 }
 
+NTSTATUS
+APIENTRY
+DodControlInterrupt(
+    IN_CONST_HANDLE                 hAdapter,
+    IN_CONST_DXGK_INTERRUPT_TYPE    InterruptType,
+    IN_BOOLEAN                      EnableInterrupt
+)
+{
+    PAGED_CODE();
+    QxlDod* pQxl = reinterpret_cast<QxlDod*>(hAdapter);
+    if (InterruptType == DXGK_INTERRUPT_DISPLAYONLY_VSYNC)
+    {
+        pQxl->EnableVsync(EnableInterrupt);
+        return STATUS_SUCCESS;
+    }
+    return  STATUS_NOT_IMPLEMENTED;
+}
+
+NTSTATUS
+APIENTRY
+DodGetScanLine(
+    IN_CONST_HANDLE             hAdapter,
+    INOUT_PDXGKARG_GETSCANLINE  pGetScanLine
+)
+{
+    PAGED_CODE();
+    // Currently we do not see any practical use case when this procedure is called
+    // IDirectDraw has an interface for querying scan line
+    // Leave it not implemented like remote desktop does
+    // until we recognize use case for more intelligent implementation
+    DbgPrint(TRACE_LEVEL_ERROR, ("<---> %s\n", __FUNCTION__));
+    return STATUS_NOT_IMPLEMENTED;
+}
+
 //END: Paged Code
 #pragma code_seg(pop)
 
diff --git a/qxldod/driver.h b/qxldod/driver.h
index 97b9415..2dcbda4 100755
--- a/qxldod/driver.h
+++ b/qxldod/driver.h
@@ -217,6 +217,21 @@ DodSystemDisplayWrite(
     _In_  UINT  PositionX,
     _In_  UINT  PositionY);
 
+NTSTATUS
+APIENTRY
+DodControlInterrupt(
+    IN_CONST_HANDLE                 hAdapter,
+    IN_CONST_DXGK_INTERRUPT_TYPE    InterruptType,
+    IN_BOOLEAN                      EnableInterrupt
+);
+
+NTSTATUS
+APIENTRY
+DodGetScanLine(
+    IN_CONST_HANDLE             hAdapter,
+    INOUT_PDXGKARG_GETSCANLINE  pGetScanLine
+);
+
 #if DBG
 
 extern int nDebugLevel;