Allow runtime switching of AccelMethod between uxa/sna and even glamor

Section "Device"
  Option "AccelMethod" "uxa/glamor/sna"
EndSection

The appropriate backend must also be enabled at compile time for the
runtime option to be available (i.e. --enable-uxa (default) --enable-sna
--enable-glamor)

Demanded-by: Adam Jackson <ajax@redhat.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=50290
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

configure.ac

@@ -158,6 +158,43 @@ if test "x$GLAMOR" != "xno"; then
 	AC_DEFINE(USE_GLAMOR, 1, [Enable glamor acceleration])
 fi
 
+AC_ARG_WITH(default-accel,
+	    AS_HELP_STRING([--with-default-accel],
+			   [Select the default acceleration method [default=sna if enabled, otherwise uxa]]),
+			   [accel="$withval"],
+			   [accel=auto])
+
+AC_MSG_CHECKING([which acceleration method to use by default])
+if test "x$accel" = xauto; then
+	if test "x$UXA" != "xno"; then
+		accel=uxa
+	else
+		if test "x$SNA" != "xno"; then
+			accel=sna
+		fi
+	fi
+	if test "x$accel" = xauto; then
+		AC_MSG_ERROR([No default acceleration option])
+	fi
+fi
+
+if test "x$accel" = xsna; then
+	if test "x$SNA" != "xno"; then
+		AC_DEFINE(DEFAULT_ACCEL_METHOD, SNA, [Default acceleration method])
+	else
+		AC_MSG_ERROR([SNA requested as default, but is not enabled])
+	fi
+fi
+
+if test "x$accel" = xuxa; then
+	if test "x$UXA" != "xno"; then
+		AC_DEFINE(DEFAULT_ACCEL_METHOD, UXA, [Default acceleration method])
+	else
+		AC_MSG_ERROR([UXA requested as default, but is not enabled])
+	fi
+fi
+AC_MSG_RESULT($accel)
+
 AC_ARG_ENABLE(vmap,
 	      AS_HELP_STRING([--enable-vmap],
 			     [Enable use of vmap [default=no]]),
@@ -174,7 +211,6 @@ AC_ARG_ENABLE(debug,
 			     [Enables internal debugging [default=no]]),
               [DEBUG="$enableval"],
               [DEBUG=no])
-
 # Store the list of server defined optional extensions in REQUIRED_MODULES
 XORG_DRIVER_CHECK_EXT(RANDR, randrproto)
 XORG_DRIVER_CHECK_EXT(RENDER, renderproto)

src/common.h

@@ -63,7 +63,7 @@ SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 /* I830 hooks for the I810 driver setup/probe. */
 extern const OptionInfoRec *I830AvailableOptions(int chipid, int busid);
-extern void intel_init_scrn(ScrnInfoPtr scrn);
+extern Bool intel_init_scrn(ScrnInfoPtr scrn);
 
 /* Symbol lists shared by the i810 and i830 parts. */
 extern int I830EntityIndex;

src/intel_driver.c

@@ -1236,7 +1236,7 @@ static Bool I830PMEvent(int scrnIndex, pmEvent event, Bool undo)
 	return TRUE;
 }
 
-void intel_init_scrn(ScrnInfoPtr scrn)
+Bool intel_init_scrn(ScrnInfoPtr scrn)
 {
 	scrn->PreInit = I830PreInit;
 	scrn->ScreenInit = I830ScreenInit;
@@ -1247,4 +1247,5 @@ void intel_init_scrn(ScrnInfoPtr scrn)
 	scrn->FreeScreen = I830FreeScreen;
 	scrn->ValidMode = I830ValidMode;
 	scrn->PMEvent = I830PMEvent;
+	return TRUE;
 }

src/intel_glamor.c

@@ -172,6 +172,18 @@ intel_glamor_finish_access(PixmapPtr pixmap, uxa_access_t access)
 	return;
 }
 
+static Bool
+intel_glamor_enabled(intel_screen_private *intel)
+{
+	const char *s;
+
+	s = xf86GetOptString(intel->Options, ACCEL_METHOD);
+	if (s == NULL)
+		return FALSE;
+
+	return strcasecmp(s, "glamor") == 0;
+}
+
 Bool
 intel_glamor_init(ScreenPtr screen)
 {
@@ -181,6 +193,9 @@ intel_glamor_init(ScreenPtr screen)
 	if ((intel->uxa_flags & UXA_GLAMOR_EGL_INITIALIZED) == 0)
 		goto fail;
 
+	if (!intel_glamor_enabled(intel))
+		goto fail;
+
 	if (!glamor_init(screen, GLAMOR_INVERTED_Y_AXIS | GLAMOR_USE_EGL_SCREEN)) {
 		xf86DrvMsg(scrn->scrnIndex, X_ERROR,
 			   "Failed to initialize glamor.\n");

src/intel_module.c

@@ -31,6 +31,7 @@
 #include <xf86.h>
 #include <xf86_OSproc.h>
 #include <xf86cmap.h>
+#include <xf86Parser.h>
 #include <xf86drmMode.h>
 
 #include <xorgVersion.h>
@@ -292,6 +293,43 @@ static Bool has_kernel_mode_setting(struct pci_device *dev)
 	return ret == 0;
 }
 
+extern XF86ConfigPtr xf86configptr;
+
+static XF86ConfDevicePtr
+_xf86findDriver(const char *ident, XF86ConfDevicePtr p)
+{
+	while (p) {
+		if (xf86nameCompare(ident, p->dev_driver) == 0)
+			return p;
+
+		p = p->list.next;
+	}
+	return NULL;
+}
+
+static enum accel_method { UXA, SNA } get_accel_method(void)
+{
+	enum accel_method accel_method = DEFAULT_ACCEL_METHOD;
+	XF86ConfDevicePtr dev;
+
+	dev = _xf86findDriver("intel", xf86configptr->conf_device_lst);
+	if (dev && dev->dev_option_lst) {
+		const char *s;
+
+		s = xf86FindOptionValue(dev->dev_option_lst, "AccelMethod");
+		if (s ) {
+			if (strcasecmp(s, "sna") == 0)
+				accel_method = SNA;
+			else if (strcasecmp(s, "uxa") == 0)
+				accel_method = UXA;
+			else if (strcasecmp(s, "glamor") == 0)
+				accel_method = UXA;
+		}
+	}
+
+	return accel_method;
+}
+
 /*
  * intel_pci_probe --
  *
@@ -338,34 +376,35 @@ static Bool intel_pci_probe(DriverPtr		driver,
 
 	scrn = xf86ConfigPciEntity(NULL, 0, entity_num, intel_pci_chipsets,
 				   NULL, NULL, NULL, NULL, NULL);
-	if (scrn != NULL) {
-		scrn->driverVersion = INTEL_VERSION;
-		scrn->driverName = INTEL_DRIVER_NAME;
-		scrn->name = INTEL_NAME;
-		scrn->Probe = NULL;
+	if (scrn == NULL)
+		return FALSE;
+
+	scrn->driverVersion = INTEL_VERSION;
+	scrn->driverName = INTEL_DRIVER_NAME;
+	scrn->name = INTEL_NAME;
+	scrn->Probe = NULL;
 
-		switch (DEVICE_ID(device)) {
 #if !KMS_ONLY
-		case PCI_CHIP_I810:
-		case PCI_CHIP_I810_DC100:
-		case PCI_CHIP_I810_E:
-		case PCI_CHIP_I815:
-			lg_i810_init(scrn);
-			break;
+	switch (DEVICE_ID(device)) {
+	case PCI_CHIP_I810:
+	case PCI_CHIP_I810_DC100:
+	case PCI_CHIP_I810_E:
+	case PCI_CHIP_I815:
+		return lg_i810_init(scrn);
+	}
 #endif
 
-		default:
+	switch (get_accel_method()) {
 #if USE_SNA
-			sna_init_scrn(scrn, entity_num);
-#elif USE_UXA
-			intel_init_scrn(scrn);
-#else
-			scrn = NULL;
+	case SNA: return sna_init_scrn(scrn, entity_num);
 #endif
-			break;
-		}
+
+#if USE_UXA
+	case UXA: return intel_init_scrn(scrn);
+#endif
+
+	default: return FALSE;
 	}
-	return scrn != NULL;
 }
 
 #ifdef XFree86LOADER

src/intel_options.h

@@ -8,6 +8,7 @@
  */
 
 enum intel_options {
+	OPTION_ACCEL_METHOD,
 	OPTION_DRI,
 	OPTION_VIDEO_KEY,
 	OPTION_COLOR_KEY,
@@ -40,6 +41,7 @@ enum intel_options {
 };
 
 static OptionInfoRec intel_options[] = {
+	{OPTION_ACCEL_METHOD,	"AccelMethod",	OPTV_STRING,	{0},	0},
 	{OPTION_DRI,		"DRI",		OPTV_BOOLEAN,	{0},	TRUE},
 	{OPTION_COLOR_KEY,	"ColorKey",	OPTV_INTEGER,	{0},	FALSE},
 	{OPTION_VIDEO_KEY,	"VideoKey",	OPTV_INTEGER,	{0},	FALSE},

src/legacy/i810/i810_driver.c

@@ -2102,7 +2102,7 @@ lg_i810_available_options(int chipid, int busid)
 }
 
 
-void lg_i810_init(ScrnInfoPtr scrn)
+Bool lg_i810_init(ScrnInfoPtr scrn)
 {
     scrn->PreInit = I810PreInit;
     scrn->ScreenInit = I810ScreenInit;
@@ -2112,4 +2112,5 @@ void lg_i810_init(ScrnInfoPtr scrn)
     scrn->LeaveVT = I810LeaveVT;
     scrn->FreeScreen = I810FreeScreen;
     scrn->ValidMode = I810ValidMode;
+    return TRUE;
 }

src/legacy/legacy.h

@@ -1,3 +1,3 @@
 /* The old i810 (only) driver. */
 const OptionInfoRec *lg_i810_available_options(int chipid, int busid);
-void lg_i810_init(ScrnInfoPtr scrn);
+Bool lg_i810_init(ScrnInfoPtr scrn);

src/sna/sna_driver.c

@@ -1047,7 +1047,7 @@ static Bool sna_pm_event(int scrnIndex, pmEvent event, Bool undo)
 	return TRUE;
 }
 
-void sna_init_scrn(ScrnInfoPtr scrn, int entity_num)
+Bool sna_init_scrn(ScrnInfoPtr scrn, int entity_num)
 {
 	EntityInfoPtr entity;
 
@@ -1081,8 +1081,13 @@ void sna_init_scrn(ScrnInfoPtr scrn, int entity_num)
 	xf86SetEntitySharable(scrn->entityList[0]);
 
 	entity = xf86GetEntityInfo(entity_num);
+	if (!entity)
+		return FALSE;
+
 	xf86SetEntityInstanceForScreen(scrn,
 				       entity->index,
 				       xf86GetNumEntityInstances(entity->index)-1);
 	free(entity);
+
+	return TRUE;
 }

src/sna/sna_module.h

@@ -1 +1 @@
-void sna_init_scrn(ScrnInfoPtr scrn, int entity_num);
+Bool sna_init_scrn(ScrnInfoPtr scrn, int entity_num);