diff options
Diffstat (limited to 'xorg-server/hw/kdrive/src/ktest.c')
-rw-r--r-- | xorg-server/hw/kdrive/src/ktest.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/xorg-server/hw/kdrive/src/ktest.c b/xorg-server/hw/kdrive/src/ktest.c new file mode 100644 index 000000000..150af5639 --- /dev/null +++ b/xorg-server/hw/kdrive/src/ktest.c @@ -0,0 +1,76 @@ +/* + * 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. + */ + +#ifdef HAVE_CONFIG_H +#include <kdrive-config.h> +#endif +#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; +} |