Initial import of the DRM (direct rendering manager).

This is the kernel part necessary for DRI support in X. Disabled for now
because it still has a few bugs, but now I can work on it in tree. Also
requires the requisite bits in X, which are currently under discussion
on how to deal with them with privsep. ported from a combination of the
free and netbsd implementations.

Known bugs:
1) only the first occurence of X in any session will have dri, after
that something prevents it working.
2) if the machine does not have a dri capable card, the kernel panics.
Something's up in one of the probe functions. I haven't been able to
find it though.
3) radeon cards need to be forced to use PCI mode otherwise they get
into an infinite loop.

This is known to at least kinda work with SiS, radeons in pci mode and
intel cards.

ok deraadt, kinda ok art, a few other people had a quick look.

1 files changed, 139 insertions, 0 deletions

diff --git a/sys/dev/pci/drm/drm_vm.c b/sys/dev/pci/drm/drm_vm.c
new file mode 100644
index 00000000000..1e5ced998e5
--- /dev/null
+++ b/sys/dev/pci/drm/drm_vm.c
@@ -0,0 +1,139 @@
+/*-
+ * Copyright 2003 Eric Anholt
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * ERIC ANHOLT BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+ * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/** @file drm_vm.c
+ * Support code for mmaping of DRM maps.
+ */
+
+#include "drmP.h"
+#include "drm.h"
+
+#if defined(__FreeBSD__) && __FreeBSD_version >= 500102
+int drm_mmap(struct cdev *kdev, vm_offset_t offset, vm_paddr_t *paddr,
+    int prot)
+#elif defined(__FreeBSD__)
+int drm_mmap(dev_t kdev, vm_offset_t offset, int prot)
+#elif defined(__NetBSD__) || defined(__OpenBSD__)
+paddr_t drm_mmap(dev_t kdev, off_t offset, int prot)
+#endif
+{
+	drm_device_t *dev = drm_get_device_from_kdev(kdev);
+	drm_local_map_t *map;
+	drm_file_t *priv;
+	drm_map_type_t type;
+#ifdef __FreeBSD__
+	vm_paddr_t phys;
+#else
+	paddr_t phys;
+#endif
+
+	DRM_LOCK();
+	priv = drm_find_file_by_proc(dev, DRM_CURPROC);
+	DRM_UNLOCK();
+	if (priv == NULL) {
+		DRM_ERROR("can't find authenticator\n");
+		return EINVAL;
+	}
+
+	if (!priv->authenticated)
+		return EACCES;
+
+	if (dev->dma && offset >= 0 && offset < ptoa(dev->dma->page_count)) {
+		drm_device_dma_t *dma = dev->dma;
+
+		DRM_SPINLOCK(&dev->dma_lock);
+
+		if (dma->pagelist != NULL) {
+			unsigned long page = offset >> PAGE_SHIFT;
+			unsigned long phys = dma->pagelist[page];
+
+#if defined(__FreeBSD__) && __FreeBSD_version >= 500102
+			*paddr = phys;
+			DRM_SPINUNLOCK(&dev->dma_lock);
+			return 0;
+#else
+			DRM_SPINUNLOCK(&dev->dma_lock);
+			return atop(phys);
+#endif
+		} else {
+			DRM_SPINUNLOCK(&dev->dma_lock);
+			return -1;
+		}
+	}
+
+				/* A sequential search of a linked list is
+				   fine here because: 1) there will only be
+				   about 5-10 entries in the list and, 2) a
+				   DRI client only has to do this mapping
+				   once, so it doesn't have to be optimized
+				   for performance, even if the list was a
+				   bit longer. */
+	DRM_LOCK();
+	TAILQ_FOREACH(map, &dev->maplist, link) {
+		if (offset >= map->offset && offset < map->offset + map->size)
+			break;
+	}
+
+	if (map == NULL) {
+		DRM_UNLOCK();
+		DRM_DEBUG("can't find map\n");
+		return -1;
+	}
+	if (((map->flags&_DRM_RESTRICTED) && !DRM_SUSER(DRM_CURPROC))) {
+		DRM_UNLOCK();
+		DRM_DEBUG("restricted map\n");
+		return -1;
+	}
+	type = map->type;
+	DRM_UNLOCK();
+
+	switch (type) {
+	case _DRM_FRAME_BUFFER:
+	case _DRM_REGISTERS:
+	case _DRM_AGP:
+		phys = offset;
+		break;
+	case _DRM_CONSISTENT:
+#ifdef __FreeBSD__
+		phys = vtophys((char *)map->handle + (offset - map->offset));
+#else
+		phys = vtophys((paddr_t)map->handle + (offset - map->offset));
+#endif
+		break;
+	case _DRM_SCATTER_GATHER:
+	case _DRM_SHM:
+		phys = vtophys(offset);
+		break;
+	default:
+		DRM_ERROR("bad map type %d\n", type);
+		return -1;	/* This should never happen. */
+	}
+
+#if defined(__FreeBSD__) && __FreeBSD_version >= 500102
+	*paddr = phys;
+	return 0;
+#else
+	return atop(phys);
+#endif
+}
+