1 files changed, 374 insertions, 0 deletions
diff --git a/hw/xfree86/exa/exaoffscreen.c b/hw/xfree86/exa/exaoffscreen.c
new file mode 100644
index 000000000..def3fbdbb
--- /dev/null
+++ b/hw/xfree86/exa/exaoffscreen.c
@@ -0,0 +1,374 @@
+/*
+ * Copyright © 2003 Anders Carlsson
+ *
+ * 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 Anders Carlsson not be used in
+ * advertising or publicity pertaining to distribution of the software without
+ * specific, written prior permission.  Anders Carlsson makes no
+ * representations about the suitability of this software for any purpose.  It
+ * is provided "as is" without express or implied warranty.
+ *
+ * ANDERS CARLSSON DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL ANDERS CARLSSON 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.
+ */
+
+#include "exaPriv.h"
+
+#define DEBUG_OFFSCREEN 1
+#if DEBUG_OFFSCREEN
+#define DBG_OFFSCREEN(a) ErrorF a
+#else
+#define DBG_OFFSCREEN(a)
+#endif
+
+#if DEBUG_OFFSCREEN
+static void
+ExaOffscreenValidate (ScreenPtr pScreen)
+{
+    ExaScreenPriv (pScreen);
+    ExaOffscreenArea *prev = 0, *area;
+
+    assert (pExaScr->info->card.offScreenAreas->area.offset == 0);
+    for (area = pExaScr->info->card.offScreenAreas; area; area = area->next)
+    {
+	if (prev)
+	    assert (prev->area.offset + prev->area.size == area->area.offset);
+
+	prev = area;
+    }
+    assert (prev->area.offset + prev->area.size == pExaScr->info->card.memorySize);
+}
+#else
+#define ExaOffscreenValidate(s)
+#endif
+
+static ExaOffscreenArea *
+ExaOffscreenKickOut (ScreenPtr pScreen, ExaOffscreenArea *area)
+{
+    if (area->save)
+	(*area->save) (pScreen, area);
+    return exaOffscreenFree (pScreen, area);
+}
+
+ExaOffscreenArea *
+exaOffscreenAlloc (ScreenPtr pScreen, int size, int align,
+                   Bool locked,
+                   ExaOffscreenSaveProc save,
+                   pointer privData)
+{
+    ExaOffscreenArea *area, *begin, *best;
+    ExaScreenPriv (pScreen);
+    int tmp, real_size = 0, best_score;
+#if DEBUG_OFFSCREEN
+    static int number = 0;
+    ErrorF("================= ============ allocating a new pixmap %d\n", ++number);
+#endif
+
+    ExaOffscreenValidate (pScreen);
+    if (!align)
+	align = 1;
+
+    if (!size)
+    {
+	DBG_OFFSCREEN (("Alloc 0x%x -> EMPTY\n", size));
+	return NULL;
+    }
+
+    /* throw out requests that cannot fit */
+    if (size > (pExaScr->info->card.memorySize - pExaScr->info->card.offScreenBase))
+    {
+	DBG_OFFSCREEN (("Alloc 0x%x -> TOBIG\n", size));
+	return NULL;
+    }
+
+    /* Try to find a free space that'll fit. */
+    for (area = pExaScr->info->card.offScreenAreas; area; area = area->next)
+    {
+	/* skip allocated areas */
+	if (area->state != ExaOffscreenAvail)
+	    continue;
+
+	/* adjust size to match alignment requirement */
+	real_size = size;
+	tmp = area->offset % align;
+	if (tmp)
+	    real_size += (align - tmp);
+
+	/* does it fit? */
+	if (real_size <= area->size)
+	    break;
+    }
+
+    if (!area)
+    {
+	/*
+	 * Kick out existing users to make space.
+	 *
+	 * First, locate a region which can hold the desired object.
+	 */
+
+	/* prev points at the first object to boot */
+	best = NULL;
+	best_score = MAXINT;
+	for (begin = pExaScr->info->card.offScreenAreas; begin != NULL;
+	     begin = begin->next)
+	{
+	    int avail, score;
+	    ExaOffscreenArea *scan;
+
+	    if (begin->state == ExaOffscreenLocked)
+		continue;
+
+	    /* adjust size to match alignment requirement */
+	    real_size = size;
+	    tmp = begin->offset % align;
+	    if (tmp)
+		real_size += (align - tmp);
+
+	    avail = 0;
+	    score = 0;
+	    /* now see if we can make room here, and how "costly" it'll be. */
+	    for (scan = begin; scan != NULL; scan = scan->next)
+	    {
+		if (scan->state == ExaOffscreenLocked) {
+		    /* Can't make room here, start after this locked area. */
+		    begin = scan->next;
+		    break;
+		}
+		/* Score should only be non-zero for ExaOffscreenRemovable */
+		score += scan->score;
+		avail += scan->size;
+		if (avail >= real_size)
+		    break;
+	    }
+	    /* Is it the best option we've found so far? */
+	    if (avail >= real_size && score < best_score) {
+		best = begin;
+		best_score = score;
+	    }
+	}
+	area = best;
+	if (!area)
+	{
+	    DBG_OFFSCREEN (("Alloc 0x%x -> NOSPACE\n", size));
+	    /* Could not allocate memory */
+	    ExaOffscreenValidate (pScreen);
+	    return NULL;
+	}
+
+	/* adjust size to match alignment requirement */
+	real_size = size;
+	tmp = begin->offset % align;
+	if (tmp)
+	    real_size += (align - tmp);
+
+	/*
+	 * Kick out first area if in use
+	 */
+	if (area->state != ExaOffscreenAvail)
+	    area = ExaOffscreenKickOut (pScreen, area);
+	/*
+	 * Now get the system to merge the other needed areas together
+	 */
+	while (area->size < real_size)
+	{
+	    assert (area->next && area->next->state == ExaOffscreenRemovable);
+	    (void) ExaOffscreenKickOut (pScreen, area->next);
+	}
+    }
+
+    /* save extra space in new area */
+    if (real_size < area->size)
+    {
+	ExaOffscreenArea   *new_area = xalloc (sizeof (ExaOffscreenArea));
+	if (!new_area)
+	    return NULL;
+	new_area->offset = area->offset + real_size;
+	new_area->size = area->size - real_size;
+	new_area->state = ExaOffscreenAvail;
+	new_area->save = 0;
+	new_area->score = 0;
+	new_area->next = area->next;
+	area->next = new_area;
+	area->size = real_size;
+    }
+    /*
+     * Mark this area as in use
+     */
+    if (locked)
+	area->state = ExaOffscreenLocked;
+    else
+	area->state = ExaOffscreenRemovable;
+    area->privData = privData;
+    area->save = save;
+    area->score = 0;
+
+    area->save_offset = area->offset;
+    area->offset = (area->offset + align - 1) & ~(align - 1);
+
+    ExaOffscreenValidate (pScreen);
+
+    DBG_OFFSCREEN (("Alloc 0x%x -> 0x%x\n", size, area->offset));
+    return area;
+}
+
+void
+ExaOffscreenSwapOut (ScreenPtr pScreen)
+{
+    ExaScreenPriv (pScreen);
+
+    ExaOffscreenValidate (pScreen);
+    /* loop until a single free area spans the space */
+    for (;;)
+    {
+	ExaOffscreenArea *area = pExaScr->info->card.offScreenAreas;
+
+	if (!area)
+	    break;
+	if (area->state == ExaOffscreenAvail)
+	{
+	    area = area->next;
+	    if (!area)
+		break;
+	}
+	assert (area->state != ExaOffscreenAvail);
+	(void) ExaOffscreenKickOut (pScreen, area);
+	ExaOffscreenValidate (pScreen);
+    }
+    ExaOffscreenValidate (pScreen);
+    ExaOffscreenFini (pScreen);
+}
+
+void
+ExaOffscreenSwapIn (ScreenPtr pScreen)
+{
+    exaOffscreenInit (pScreen);
+}
+
+/* merge the next free area into this one */
+static void
+ExaOffscreenMerge (ExaOffscreenArea *area)
+{
+    ExaOffscreenArea	*next = area->next;
+
+    /* account for space */
+    area->size += next->size;
+    /* frob pointer */
+    area->next = next->next;
+    xfree (next);
+}
+
+ExaOffscreenArea *
+exaOffscreenFree (ScreenPtr pScreen, ExaOffscreenArea *area)
+{
+    ExaScreenPriv(pScreen);
+    ExaOffscreenArea	*next = area->next;
+    ExaOffscreenArea	*prev;
+
+    DBG_OFFSCREEN (("Free 0x%x -> 0x%x\n", area->size, area->offset));
+    ExaOffscreenValidate (pScreen);
+
+    area->state = ExaOffscreenAvail;
+    area->save = 0;
+    area->offset = area->save_offset;
+    area->score = 0;
+    /*
+     * Find previous area
+     */
+    if (area == pExaScr->info->card.offScreenAreas)
+	prev = 0;
+    else
+	for (prev = pExaScr->info->card.offScreenAreas; prev; prev = prev->next)
+	    if (prev->next == area)
+		break;
+
+    /* link with next area if free */
+    if (next && next->state == ExaOffscreenAvail)
+	ExaOffscreenMerge (area);
+
+    /* link with prev area if free */
+    if (prev && prev->state == ExaOffscreenAvail)
+    {
+	area = prev;
+	ExaOffscreenMerge (area);
+    }
+
+    ExaOffscreenValidate (pScreen);
+    DBG_OFFSCREEN(("\tdone freeing\n"));
+    return area;
+}
+
+void
+ExaOffscreenMarkUsed (PixmapPtr pPixmap)
+{
+    ExaPixmapPriv (pPixmap);
+    ExaScreenPriv (pPixmap->drawable.pScreen);
+    static int iter = 0;
+
+    if (!pExaPixmap->area)
+	return;
+
+    /* The numbers here are arbitrary.  We may want to tune these. */
+    pExaPixmap->area->score += 100;
+    if (++iter == 10) {
+	ExaOffscreenArea *area;
+	for (area = pExaScr->info->card.offScreenAreas; area != NULL;
+	     area = area->next)
+	{
+	    if (area->state == ExaOffscreenRemovable)
+		area->score = (area->score * 7) / 8;
+	}
+    }
+}
+
+Bool
+exaOffscreenInit (ScreenPtr pScreen)
+{
+    ExaScreenPriv (pScreen);
+    ExaOffscreenArea *area;
+
+    /* Allocate a big free area */
+    area = xalloc (sizeof (ExaOffscreenArea));
+
+    if (!area)
+	return FALSE;
+
+
+    area->state = ExaOffscreenAvail;
+    area->offset = pExaScr->info->card.offScreenBase;
+    area->size = pExaScr->info->card.memorySize - area->offset;
+    area->save = 0;
+    area->next = NULL;
+    area->score = 0;
+
+    ErrorF("============ initial memory block of %d\n", area->size);
+
+    /* Add it to the free areas */
+    pExaScr->info->card.offScreenAreas = area;
+
+    ExaOffscreenValidate (pScreen);
+
+    return TRUE;
+}
+
+void
+ExaOffscreenFini (ScreenPtr pScreen)
+{
+    ExaScreenPriv (pScreen);
+    ExaOffscreenArea *area;
+
+    /* just free all of the area records */
+    while ((area = pExaScr->info->card.offScreenAreas))
+    {
+	pExaScr->info->card.offScreenAreas = area->next;
+	xfree (area);
+    }
+}