1 files changed, 76 insertions, 0 deletions
diff --git a/hw/kdrive/src/ktest.c b/hw/kdrive/src/ktest.c
new file mode 100644
index 000000000..f4505406d
--- /dev/null
+++ b/hw/kdrive/src/ktest.c
@@ -0,0 +1,76 @@
+/*
+ * $Id$
+ *
+ * Copyright © 1999 Keith Packard
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation, and that the name of Keith Packard not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission.  Keith Packard makes no
+ * representations about the suitability of this software for any purpose.  It
+ * is provided "as is" without express or implied warranty.
+ *
+ * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+/* $XFree86: $ */
+
+#include "kdrive.h"
+
+
+static CARD8	memoryPatterns[] = { 0xff, 0x00, 0x5a, 0xa5, 0xaa, 0x55 };
+
+#define NUM_PATTERNS	(sizeof (memoryPatterns) / sizeof (memoryPatterns[0]))
+
+Bool
+KdFrameBufferValid (CARD8 *base, int size)
+{
+    volatile CARD8  *b = (volatile CARD8 *) base;
+    CARD8	    save, test, compare;
+    int		    i, j;
+
+    b = base + (size - 1);
+    save = *b;
+
+    for (i = 0; i < NUM_PATTERNS; i++)
+    {
+	test = memoryPatterns[i];
+	*b = test;
+	for (j = 0; j < 1000; j++)
+	{
+	    compare = *b;
+	    if (compare != test)
+		return FALSE;
+	}
+    }
+    *b = save;
+    return TRUE;
+}
+
+int
+KdFrameBufferSize (CARD8 *base, int max)
+{
+    int	min, cur;
+    
+    min = 0;
+    while (min + 1 < max)
+    {
+	cur = (max + min) / 2;
+	if (KdFrameBufferValid (base, cur))
+	    min = cur;
+	else
+	    max = cur;
+    }
+    if (KdFrameBufferValid (base, max))
+	return max;
+    else
+	return min;
+}