From 5cdd2580466d245e9d521fdf3f04e4937430a653 Mon Sep 17 00:00:00 2001
From: Vincent Wei <vincent@minigui.org>
Date: Fri, 14 Jul 2023 14:06:28 +0800
Subject: [PATCH] use WaitVBlank

---
 src/newgal/drm/drmvideo.c  | 17 +++++++++++++++++
 src/newgal/fbcon/fbvideo.c | 35 ++++++++++++++++++-----------------
 src/newgal/shadow/shadow.c |  7 ++++++-
 src/newgal/sysvideo.h      |  3 +++
 4 files changed, 44 insertions(+), 18 deletions(-)

diff --git a/src/newgal/drm/drmvideo.c b/src/newgal/drm/drmvideo.c
index 30fc2e2d..8223e836 100644
--- a/src/newgal/drm/drmvideo.c
+++ b/src/newgal/drm/drmvideo.c
@@ -120,6 +120,7 @@ static int DRM_FillHWRect_Accl(_THIS, GAL_Surface *dst, GAL_Rect *rect,
         Uint32 color);
 
 static void DRM_UpdateRects(_THIS, int numrects, GAL_Rect *rects);
+static BOOL DRM_WaitVBlank(_THIS);
 static BOOL DRM_SyncUpdate(_THIS);
 static BOOL DRM_SyncUpdateAsync(_THIS);
 
@@ -2574,6 +2575,7 @@ static void* task_do_update(void *data)
         }
         else {
             vbl_ok = TRUE;
+            this->WaitVBlank = DRM_WaitVBlank;
         }
     }
 #endif
@@ -3713,6 +3715,21 @@ static void DRM_UpdateRects (_THIS, int numrects, GAL_Rect *rects)
 #endif
 }
 
+static BOOL DRM_WaitVBlank(_THIS)
+{
+    drmVBlank vbl;
+    vbl.request.type = DRM_VBLANK_RELATIVE | DRM_VBLANK_NEXTONMISS;
+    if (this->hidden->cap_vblank_high_crtc)
+        vbl.request.type |=
+            (this->hidden->crtc_idx << DRM_VBLANK_HIGH_CRTC_SHIFT);
+    vbl.request.sequence = 1;
+    vbl.request.signal = 0;
+    if (drmWaitVBlank(this->hidden->dev_fd, &vbl))
+        return FALSE;
+
+    return TRUE;
+}
+
 static BOOL DRM_SyncUpdate(_THIS)
 {
     BOOL retval = FALSE;
diff --git a/src/newgal/fbcon/fbvideo.c b/src/newgal/fbcon/fbvideo.c
index e834f7c9..a9dfee40 100644
--- a/src/newgal/fbcon/fbvideo.c
+++ b/src/newgal/fbcon/fbvideo.c
@@ -99,8 +99,6 @@ static void FB_RequestHWSurface (_THIS, const REQ_HWSURFACE* request,
         REP_HWSURFACE* reply);
 static int FB_AllocHWSurface(_THIS, GAL_Surface *surface);
 static void FB_FreeHWSurface(_THIS, GAL_Surface *surface);
-static void FB_WaitVBL(_THIS);
-static void FB_WaitIdle(_THIS);
 
 #include "../shadow-screen.h"
 #include "debug.h"
@@ -191,6 +189,19 @@ static BOOL FB_SyncUpdatePanning (_THIS)
     return TRUE;
 }
 
+static BOOL FB_WaitVBlank(_THIS)
+{
+    if (wait_vbl) {
+        wait_vbl(this);
+    }
+    else if (ioctl(console_fd, FBIO_WAITFORVSYNC, 0)) {
+        _WRN_PRINTF("Failed VSync.\n");
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
 static BOOL FB_SyncUpdate (_THIS)
 {
     if (IsRectEmpty (&this->hidden->dirty_rc))
@@ -269,8 +280,6 @@ static GAL_VideoDevice *FB_CreateDevice(int devindex)
     memset(this->hidden, 0, (sizeof *this->hidden));
     this->hidden->magic = MAGIC_SHADOW_SCREEN_HEADER;
     this->hidden->version = 0;
-    wait_vbl = FB_WaitVBL;
-    wait_idle = FB_WaitIdle;
 
     /* Set the function pointers */
     this->VideoInit = FB_VideoInit;
@@ -894,6 +903,11 @@ static GAL_Surface *FB_SetVideoMode(_THIS, GAL_Surface *current,
         }
     }
 
+    if (FB_WaitVBlank(this))
+        this->WaitVBlank = FB_WaitVBlank;
+    else
+        _WRN_PRINTF("The FBCon device does not support VSync.\n");
+
     /* We're done */
     return (current);
 }
@@ -1176,19 +1190,6 @@ static void FB_FreeHWSurface(_THIS, GAL_Surface *surface)
     surface->hwdata = NULL;
 }
 
-static void FB_WaitVBL(_THIS)
-{
-#ifdef FBIOWAITRETRACE /* Heheh, this didn't make it into the main kernel */
-    ioctl(console_fd, FBIOWAITRETRACE, 0);
-#endif
-    return;
-}
-
-static void FB_WaitIdle(_THIS)
-{
-    return;
-}
-
 void FB_SavePaletteTo(_THIS, int palette_len, __u16 *area)
 {
     struct fb_cmap cmap;
diff --git a/src/newgal/shadow/shadow.c b/src/newgal/shadow/shadow.c
index ebba7a44..260784ff 100644
--- a/src/newgal/shadow/shadow.c
+++ b/src/newgal/shadow/shadow.c
@@ -630,7 +630,12 @@ static void *task_do_update(void *data)
     sem_post(&this->hidden->sync_sem);
 
     do {
-        usleep(this->hidden->update_interval * 1000);
+        if (this->WaitVBlank) {
+            this->WaitVBlank(this);
+        }
+        else {
+            usleep(this->hidden->update_interval * 1000);
+        }
 
 #if USE_UPDATE_SEM
         if (sem_wait(&this->hidden->update_sem))
diff --git a/src/newgal/sysvideo.h b/src/newgal/sysvideo.h
index 2f4f0019..ef5ccd1c 100644
--- a/src/newgal/sysvideo.h
+++ b/src/newgal/sysvideo.h
@@ -128,6 +128,9 @@ struct GAL_VideoDevice {
      */
     void (*UpdateRects)(_THIS, int numrects, GAL_Rect *rects);
 
+    /* Wait vertical blank */
+    BOOL (*WaitVBlank)(_THIS);
+
     /* Synchronize the dirty content */
     BOOL (*SyncUpdate)(_THIS);