dri2: Add pageflip/exchange support.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>

6 files changed, 104 insertions, 7 deletions

diff --git a/src/drmmode_display.c b/src/drmmode_display.c
index 4220cf5..94b19ea 100644
--- a/src/drmmode_display.c
+++ b/src/drmmode_display.c
@@ -1179,9 +1179,47 @@ drmmode_cursor_init(ScreenPtr pScreen)
 	return xf86_cursors_init(pScreen, size, size, flags);
 }
 
-#ifdef HAVE_LIBUDEV
+Bool
+drmmode_page_flip(DrawablePtr draw, PixmapPtr back, void *priv)
+{
+	ScrnInfoPtr scrn = xf86Screens[draw->pScreen->myNum];
+	xf86CrtcConfigPtr config = XF86_CRTC_CONFIG_PTR(scrn);
+	drmmode_crtc_private_ptr crtc = config->crtc[0]->driver_private;
+	drmmode_ptr mode = crtc->drmmode;
+	int ret, i, old_fb_id;
+
+	old_fb_id = mode->fb_id;
+	ret = drmModeAddFB(mode->fd, scrn->virtualX, scrn->virtualY,
+			   scrn->depth, scrn->bitsPerPixel,
+			   scrn->displayWidth * scrn->bitsPerPixel / 8,
+			   nouveau_pixmap_bo(back)->handle, &mode->fb_id);
+	if (ret) {
+		xf86DrvMsg(scrn->scrnIndex, X_WARNING,
+			   "add fb failed: %s\n", strerror(errno));
+		return FALSE;
+	}
+
+	for (i = 0; i < config->num_crtc; i++) {
+		crtc = config->crtc[i]->driver_private;
 
+		if (!config->crtc[i]->enabled)
+			continue;
 
+		ret = drmModePageFlip(mode->fd, crtc->mode_crtc->crtc_id,
+				      mode->fb_id, 0, priv);
+		if (ret) {
+			xf86DrvMsg(scrn->scrnIndex, X_WARNING,
+				   "flip queue failed: %s\n", strerror(errno));
+			return FALSE;
+		}
+	}
+
+	drmModeRmFB(mode->fd, old_fb_id);
+
+	return TRUE;
+}
+
+#ifdef HAVE_LIBUDEV
 static void
 drmmode_handle_uevents(ScrnInfoPtr scrn)
 {
diff --git a/src/nouveau_dri2.c b/src/nouveau_dri2.c
index 66fe16c..7fdfa9c 100644
--- a/src/nouveau_dri2.c
+++ b/src/nouveau_dri2.c
@@ -129,6 +129,20 @@ struct nouveau_dri2_vblank_state {
 };
 
 static Bool
+can_exchange(DrawablePtr draw, PixmapPtr dst_pix, PixmapPtr src_pix)
+{
+	ScrnInfoPtr scrn = xf86Screens[draw->pScreen->myNum];
+	NVPtr pNv = NVPTR(scrn);
+
+	return (!nouveau_exa_pixmap_is_onscreen(dst_pix) ||
+		(DRI2CanFlip(draw) && pNv->has_pageflip)) &&
+		dst_pix->drawable.width == src_pix->drawable.width &&
+		dst_pix->drawable.height == src_pix->drawable.height &&
+		dst_pix->drawable.depth == src_pix->drawable.depth &&
+		dst_pix->devKind == src_pix->devKind;
+}
+
+static Bool
 can_sync_to_vblank(DrawablePtr draw)
 {
 	ScrnInfoPtr scrn = xf86Screens[draw->pScreen->myNum];
@@ -183,9 +197,7 @@ nouveau_dri2_finish_swap(DrawablePtr draw, unsigned int frame,
 	struct nouveau_bo *dst_bo = nouveau_pixmap_bo(dst_pix);
 	struct nouveau_bo *src_bo = nouveau_pixmap_bo(src_pix);
 	struct nouveau_channel *chan = pNv->chan;
-	BoxRec box = { 0, 0, draw->width, draw->height };
-	RegionRec region;
-	int ret;
+	int type, ret;
 
 	/* Throttle on the previous frame before swapping */
 	nouveau_bo_map(dst_bo, NOUVEAU_BO_RD);
@@ -209,12 +221,40 @@ nouveau_dri2_finish_swap(DrawablePtr draw, unsigned int frame,
 		FIRE_RING(chan);
 	}
 
+	if (can_exchange(draw, dst_pix, src_pix)) {
+		type = DRI2_EXCHANGE_COMPLETE;
 
-	RegionInit(&region, &box, 0);
-	nouveau_dri2_copy_region(draw, &region, s->dst, s->src);
+		if (DRI2CanFlip(draw)) {
+			type = DRI2_FLIP_COMPLETE;
+			ret = drmmode_page_flip(draw, src_pix, s);
+			if (!ret)
+				goto out;
+		}
+
+		SWAP(s->dst->name, s->src->name);
+		SWAP(nouveau_pixmap(dst_pix)->bo, nouveau_pixmap(src_pix)->bo);
+
+	} else {
+		BoxRec box = { 0, 0, draw->width, draw->height };
+		RegionRec region;
+
+		RegionInit(&region, &box, 0);
+
+		type = DRI2_BLIT_COMPLETE;
+		nouveau_dri2_copy_region(draw, &region, s->dst, s->src);
+	}
 
+	/*
+	 * Tell the X server buffers are already swapped even if they're
+	 * not, to prevent it from blocking the client on the next
+	 * GetBuffers request (and let the client do triple-buffering).
+	 *
+	 * XXX - The DRI2SwapLimit() API will allow us to move this to
+	 *	 the flip handler with no FPS hit.
+	 */
 	DRI2SwapComplete(s->client, draw, frame, tv_sec, tv_usec,
-			 DRI2_BLIT_COMPLETE, s->func, s->data);
+			 type, s->func, s->data);
+out:
 	free(s);
 }
 
diff --git a/src/nouveau_local.h b/src/nouveau_local.h
index 5d3200a..38b861f 100644
--- a/src/nouveau_local.h
+++ b/src/nouveau_local.h
@@ -74,4 +74,10 @@ static inline int round_down_pow2(int x)
 	return 1 << log2i(x);
 }
 
+#define SWAP(x, y) do {			\
+		typeof(x) __z = (x);	\
+		(x) = (y);		\
+		(y) = __z;		\
+	} while (0)
+
 #endif
diff --git a/src/nv_driver.c b/src/nv_driver.c
index 5ef7984..fad7d6a 100644
--- a/src/nv_driver.c
+++ b/src/nv_driver.c
@@ -28,6 +28,7 @@
 #include "xf86int10.h"
 #include "xf86drm.h"
 #include "xf86drmMode.h"
+#include "nouveau_drm.h"
 
 /*
  * Forward definitions for the functions that make up the driver.
@@ -586,6 +587,7 @@ NVPreInit(ScrnInfoPtr pScrn, int flags)
 	struct nouveau_device *dev;
 	NVPtr pNv;
 	MessageType from;
+	uint64_t v;
 	int ret, i;
 
 	if (flags & PROBE_DETECT) {
@@ -792,6 +794,15 @@ NVPreInit(ScrnInfoPtr pScrn, int flags)
 			   pNv->glx_vblank ? "enabled" : "disabled");
 	}
 
+#ifdef NOUVEAU_GETPARAM_HAS_PAGEFLIP
+	ret = nouveau_device_get_param(pNv->dev,
+				       NOUVEAU_GETPARAM_HAS_PAGEFLIP, &v);
+	if (!ret)
+		pNv->has_pageflip = v;
+#else
+	(void)v;
+#endif
+
 	if(xf86GetOptValInteger(pNv->Options, OPTION_VIDEO_KEY, &(pNv->videoKey))) {
 		xf86DrvMsg(pScrn->scrnIndex, X_CONFIG, "video key set to 0x%x\n",
 					pNv->videoKey);
diff --git a/src/nv_proto.h b/src/nv_proto.h
index ba234b3..8514af9 100644
--- a/src/nv_proto.h
+++ b/src/nv_proto.h
@@ -7,6 +7,7 @@ void drmmode_adjust_frame(ScrnInfoPtr pScrn, int x, int y, int flags);
 void drmmode_remove_fb(ScrnInfoPtr pScrn);
 Bool drmmode_cursor_init(ScreenPtr pScreen);
 void drmmode_fbcon_copy(ScreenPtr pScreen);
+Bool drmmode_page_flip(DrawablePtr draw, PixmapPtr back, void *priv);
 void drmmode_screen_init(ScreenPtr pScreen);
 void drmmode_screen_fini(ScreenPtr pScreen);
 
diff --git a/src/nv_type.h b/src/nv_type.h
index a9c693f..94c385a 100644
--- a/src/nv_type.h
+++ b/src/nv_type.h
@@ -51,6 +51,7 @@ typedef struct _NVRec {
     Bool		wfb_enabled;
     Bool		tiled_scanout;
     Bool		glx_vblank;
+    Bool		has_pageflip;
     ScreenBlockHandlerProcPtr BlockHandler;
     CreateScreenResourcesProcPtr CreateScreenResources;
     CloseScreenProcPtr  CloseScreen;