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Diffstat (limited to 'xorg-server/hw/xfree86/common/xf86Mode.c')
-rw-r--r--xorg-server/hw/xfree86/common/xf86Mode.c200
1 files changed, 185 insertions, 15 deletions
diff --git a/xorg-server/hw/xfree86/common/xf86Mode.c b/xorg-server/hw/xfree86/common/xf86Mode.c
index 949d4fcfa..5d30a782c 100644
--- a/xorg-server/hw/xfree86/common/xf86Mode.c
+++ b/xorg-server/hw/xfree86/common/xf86Mode.c
@@ -26,6 +26,52 @@
*/
/*
+ * LCM() and scanLineWidth() are:
+ *
+ * Copyright 1997 through 2004 by Marc Aurele La France (TSI @ UQV), tsi@xfree86.org
+ *
+ * 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 Marc Aurele La France not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. Marc Aurele La France makes no representations
+ * about the suitability of this software for any purpose. It is provided
+ * "as-is" without express or implied warranty.
+ *
+ * MARC AURELE LA FRANCE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
+ * EVENT SHALL MARC AURELE LA FRANCE 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.
+ *
+ * Copyright 1990,91,92,93 by Thomas Roell, Germany.
+ * Copyright 1991,92,93 by SGCS (Snitily Graphics Consulting Services), USA.
+ *
+ * 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 Thomas Roell nor
+ * SGCS be used in advertising or publicity pertaining to distribution
+ * of the software without specific, written prior permission.
+ * Thomas Roell nor SGCS makes no representations about the suitability
+ * of this software for any purpose. It is provided "as is" without
+ * express or implied warranty.
+ *
+ * THOMAS ROELL AND SGCS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS
+ * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS, IN NO EVENT SHALL THOMAS ROELL OR SGCS 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.
+ */
+
+/*
* Authors: Dirk Hohndel <hohndel@XFree86.Org>
* David Dawes <dawes@XFree86.Org>
* Marc La France <tsi@XFree86.Org>
@@ -42,7 +88,6 @@
#include "xf86Modes.h"
#include "os.h"
#include "servermd.h"
-#include "mibank.h"
#include "globals.h"
#include "xf86.h"
#include "xf86Priv.h"
@@ -1126,6 +1171,131 @@ found:
return 1;
}
+/* Least common multiple */
+static unsigned int
+LCM(unsigned int x, unsigned int y)
+{
+ unsigned int m = x, n = y, o;
+
+ while ((o = m % n))
+ {
+ m = n;
+ n = o;
+ }
+
+ return (x / n) * y;
+}
+
+/*
+ * Given various screen attributes, determine the minimum scanline width such
+ * that each scanline is server and DDX padded and any pixels with imbedded
+ * bank boundaries are off-screen. This function returns -1 if such a width
+ * cannot exist.
+ */
+static int
+scanLineWidth(
+ unsigned int xsize, /* pixels */
+ unsigned int ysize, /* pixels */
+ unsigned int width, /* pixels */
+ unsigned long BankSize, /* char's */
+ PixmapFormatRec *pBankFormat,
+ unsigned int nWidthUnit /* bits */
+)
+{
+ unsigned long nBitsPerBank, nBitsPerScanline, nBitsPerScanlinePadUnit;
+ unsigned long minBitsPerScanline, maxBitsPerScanline;
+
+ /* Sanity checks */
+
+ if (!nWidthUnit || !pBankFormat)
+ return -1;
+
+ nBitsPerBank = BankSize * 8;
+ if (nBitsPerBank % pBankFormat->scanlinePad)
+ return -1;
+
+ if (xsize > width)
+ width = xsize;
+ nBitsPerScanlinePadUnit = LCM(pBankFormat->scanlinePad, nWidthUnit);
+ nBitsPerScanline =
+ (((width * pBankFormat->bitsPerPixel) + nBitsPerScanlinePadUnit - 1) /
+ nBitsPerScanlinePadUnit) * nBitsPerScanlinePadUnit;
+ width = nBitsPerScanline / pBankFormat->bitsPerPixel;
+
+ if (!xsize || !(nBitsPerBank % pBankFormat->bitsPerPixel))
+ return (int)width;
+
+ /*
+ * Scanlines will be server-pad aligned at this point. They will also be
+ * a multiple of nWidthUnit bits long. Ensure that pixels with imbedded
+ * bank boundaries are off-screen.
+ *
+ * It seems reasonable to limit total frame buffer size to 1/16 of the
+ * theoretical maximum address space size. On a machine with 32-bit
+ * addresses (to 8-bit quantities) this turns out to be 256MB. Not only
+ * does this provide a simple limiting condition for the loops below, but
+ * it also prevents unsigned long wraparounds.
+ */
+ if (!ysize)
+ return -1;
+
+ minBitsPerScanline = xsize * pBankFormat->bitsPerPixel;
+ if (minBitsPerScanline > nBitsPerBank)
+ return -1;
+
+ if (ysize == 1)
+ return (int)width;
+
+ maxBitsPerScanline =
+ (((unsigned long)(-1) >> 1) - minBitsPerScanline) / (ysize - 1);
+ while (nBitsPerScanline <= maxBitsPerScanline)
+ {
+ unsigned long BankBase, BankUnit;
+
+ BankUnit = ((nBitsPerBank + nBitsPerScanline - 1) / nBitsPerBank) *
+ nBitsPerBank;
+ if (!(BankUnit % nBitsPerScanline))
+ return (int)width;
+
+ for (BankBase = BankUnit; ; BankBase += nBitsPerBank)
+ {
+ unsigned long x, y;
+
+ y = BankBase / nBitsPerScanline;
+ if (y >= ysize)
+ return (int)width;
+
+ x = BankBase % nBitsPerScanline;
+ if (!(x % pBankFormat->bitsPerPixel))
+ continue;
+
+ if (x < minBitsPerScanline)
+ {
+ /*
+ * Skip ahead certain widths by dividing the excess scanline
+ * amongst the y's.
+ */
+ y *= nBitsPerScanlinePadUnit;
+ nBitsPerScanline +=
+ ((x + y - 1) / y) * nBitsPerScanlinePadUnit;
+ width = nBitsPerScanline / pBankFormat->bitsPerPixel;
+ break;
+ }
+
+ if (BankBase != BankUnit)
+ continue;
+
+ if (!(nBitsPerScanline % x))
+ return (int)width;
+
+ BankBase = ((nBitsPerScanline - minBitsPerScanline) /
+ (nBitsPerScanline - x)) * BankUnit;
+ }
+ }
+
+ return -1;
+}
+
/*
* xf86ValidateModes
*
@@ -1312,7 +1482,7 @@ xf86ValidateModes(ScrnInfoPtr scrp, DisplayModePtr availModes,
memcpy(storeClockRanges, cp, sizeof(ClockRange));
}
- /* Determine which pixmap format to pass to miScanLineWidth() */
+ /* Determine which pixmap format to pass to scanLineWidth() */
if (scrp->depth > 4)
BankFormat = &scrp->fbFormat;
else
@@ -1363,15 +1533,15 @@ xf86ValidateModes(ScrnInfoPtr scrp, DisplayModePtr availModes,
for (i = 0; linePitches[i] != 0; i++) {
if ((linePitches[i] >= virtualX) &&
(linePitches[i] ==
- miScanLineWidth(virtualX, virtualY, linePitches[i],
- apertureSize, BankFormat, pitchInc))) {
+ scanLineWidth(virtualX, virtualY, linePitches[i],
+ apertureSize, BankFormat, pitchInc))) {
linePitch = linePitches[i];
break;
}
}
} else {
- linePitch = miScanLineWidth(virtualX, virtualY, minPitch,
- apertureSize, BankFormat, pitchInc);
+ linePitch = scanLineWidth(virtualX, virtualY, minPitch,
+ apertureSize, BankFormat, pitchInc);
}
if ((linePitch < minPitch) || (linePitch > maxPitch)) {
@@ -1396,8 +1566,8 @@ xf86ValidateModes(ScrnInfoPtr scrp, DisplayModePtr availModes,
/* XXX this doesn't take m{in,ax}Pitch into account; oh well */
inferred_virtual = inferVirtualSize(scrp, availModes, &virtX, &virtY);
if (inferred_virtual)
- linePitch = miScanLineWidth(virtX, virtY, minPitch, apertureSize,
- BankFormat, pitchInc);
+ linePitch = scanLineWidth(virtX, virtY, minPitch, apertureSize,
+ BankFormat, pitchInc);
}
/* Print clock ranges and scaled clocks */
@@ -1609,8 +1779,8 @@ xf86ValidateModes(ScrnInfoPtr scrp, DisplayModePtr availModes,
if ((linePitches[i] >= newVirtX) &&
(linePitches[i] >= linePitch) &&
(linePitches[i] ==
- miScanLineWidth(newVirtX, newVirtY, linePitches[i],
- apertureSize, BankFormat, pitchInc))) {
+ scanLineWidth(newVirtX, newVirtY, linePitches[i],
+ apertureSize, BankFormat, pitchInc))) {
newLinePitch = linePitches[i];
break;
}
@@ -1618,9 +1788,9 @@ xf86ValidateModes(ScrnInfoPtr scrp, DisplayModePtr availModes,
} else {
if (linePitch < minPitch)
linePitch = minPitch;
- newLinePitch = miScanLineWidth(newVirtX, newVirtY, linePitch,
- apertureSize, BankFormat,
- pitchInc);
+ newLinePitch = scanLineWidth(newVirtX, newVirtY, linePitch,
+ apertureSize, BankFormat,
+ pitchInc);
}
if ((newLinePitch < minPitch) || (newLinePitch > maxPitch)) {
p->status = MODE_BAD_WIDTH;
@@ -1682,8 +1852,8 @@ xf86ValidateModes(ScrnInfoPtr scrp, DisplayModePtr availModes,
virtX, virtY, vx, vy);
virtX = vx;
virtY = vy;
- linePitch = miScanLineWidth(vx, vy, minPitch, apertureSize,
- BankFormat, pitchInc);
+ linePitch = scanLineWidth(vx, vy, minPitch, apertureSize,
+ BankFormat, pitchInc);
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-07 23:18:59 +0000