From 702a7ad1a9d2e195dceea2635d7497e201a3e505 Mon Sep 17 00:00:00 2001
From: Patrice Mandin <patmandin@gmail.com>
Date: Mon, 13 Oct 2008 20:50:20 +0000
Subject: [PATCH] Disable Xbios video driver if FVDI present, but still allow
 it to be used when setting SDL_VIDEODRIVER

---
 src/video/xbios/SDL_xbios.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/src/video/xbios/SDL_xbios.c b/src/video/xbios/SDL_xbios.c
index 9cbb4a8ac..23d4e7129 100644
--- a/src/video/xbios/SDL_xbios.c
+++ b/src/video/xbios/SDL_xbios.c
@@ -53,6 +53,10 @@
 
 #define XBIOS_VID_DRIVER_NAME "xbios"
 
+#ifndef C_fVDI
+#define C_fVDI 0x66564449L
+#endif
+
 /* Debug print info */
 #if 0
 #define DEBUG_PRINT(what) \
@@ -95,6 +99,8 @@ static unsigned long	F30_palette[256];
 static int XBIOS_Available(void)
 {
 	unsigned long cookie_vdo, cookie_mil, cookie_hade, cookie_scpn;
+	unsigned long cookie_fvdi;
+	const char *envr = SDL_getenv("SDL_VIDEODRIVER");
 
 	/* Milan/Hades Atari clones do not have an Atari video chip */
 	if ( (Getcookie(C__MIL, &cookie_mil) == C_FOUND) ||
@@ -102,6 +108,17 @@ static int XBIOS_Available(void)
 		return 0;
 	}
 
+	/* fVDI means graphic card, so no Xbios with it */
+	if (Getcookie(C_fVDI, &cookie_fvdi) == C_FOUND) {
+		if (!envr) {
+			return 0;
+		}
+		if (SDL_strcmp(envr, XBIOS_VID_DRIVER_NAME)!=0) {
+			return 0;
+		}
+		/* Except if we force Xbios usage, through env var */
+	}
+
 	/* Cookie _VDO present ? if not, assume ST machine */
 	if (Getcookie(C__VDO, &cookie_vdo) != C_FOUND) {
 		cookie_vdo = VDO_ST << 16;