Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 1487 insertions, 0 deletions

diff --git a/kernel/drivers/gpu/drm/omapdrm/omap_gem.c b/kernel/drivers/gpu/drm/omapdrm/omap_gem.c
new file mode 100644
index 000000000..e9718b99a
--- /dev/null
+++ b/kernel/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -0,0 +1,1487 @@
+/*
+ * drivers/gpu/drm/omapdrm/omap_gem.c
+ *
+ * Copyright (C) 2011 Texas Instruments
+ * Author: Rob Clark <rob.clark@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#include <linux/spinlock.h>
+#include <linux/shmem_fs.h>
+#include <drm/drm_vma_manager.h>
+
+#include "omap_drv.h"
+#include "omap_dmm_tiler.h"
+
+/* remove these once drm core helpers are merged */
+struct page **_drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask);
+void _drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
+		bool dirty, bool accessed);
+int _drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
+
+/*
+ * GEM buffer object implementation.
+ */
+
+#define to_omap_bo(x) container_of(x, struct omap_gem_object, base)
+
+/* note: we use upper 8 bits of flags for driver-internal flags: */
+#define OMAP_BO_DMA			0x01000000	/* actually is physically contiguous */
+#define OMAP_BO_EXT_SYNC	0x02000000	/* externally allocated sync object */
+#define OMAP_BO_EXT_MEM		0x04000000	/* externally allocated memory */
+
+
+struct omap_gem_object {
+	struct drm_gem_object base;
+
+	struct list_head mm_list;
+
+	uint32_t flags;
+
+	/** width/height for tiled formats (rounded up to slot boundaries) */
+	uint16_t width, height;
+
+	/** roll applied when mapping to DMM */
+	uint32_t roll;
+
+	/**
+	 * If buffer is allocated physically contiguous, the OMAP_BO_DMA flag
+	 * is set and the paddr is valid.  Also if the buffer is remapped in
+	 * TILER and paddr_cnt > 0, then paddr is valid.  But if you are using
+	 * the physical address and OMAP_BO_DMA is not set, then you should
+	 * be going thru omap_gem_{get,put}_paddr() to ensure the mapping is
+	 * not removed from under your feet.
+	 *
+	 * Note that OMAP_BO_SCANOUT is a hint from userspace that DMA capable
+	 * buffer is requested, but doesn't mean that it is.  Use the
+	 * OMAP_BO_DMA flag to determine if the buffer has a DMA capable
+	 * physical address.
+	 */
+	dma_addr_t paddr;
+
+	/**
+	 * # of users of paddr
+	 */
+	uint32_t paddr_cnt;
+
+	/**
+	 * tiler block used when buffer is remapped in DMM/TILER.
+	 */
+	struct tiler_block *block;
+
+	/**
+	 * Array of backing pages, if allocated.  Note that pages are never
+	 * allocated for buffers originally allocated from contiguous memory
+	 */
+	struct page **pages;
+
+	/** addresses corresponding to pages in above array */
+	dma_addr_t *addrs;
+
+	/**
+	 * Virtual address, if mapped.
+	 */
+	void *vaddr;
+
+	/**
+	 * sync-object allocated on demand (if needed)
+	 *
+	 * Per-buffer sync-object for tracking pending and completed hw/dma
+	 * read and write operations.  The layout in memory is dictated by
+	 * the SGX firmware, which uses this information to stall the command
+	 * stream if a surface is not ready yet.
+	 *
+	 * Note that when buffer is used by SGX, the sync-object needs to be
+	 * allocated from a special heap of sync-objects.  This way many sync
+	 * objects can be packed in a page, and not waste GPU virtual address
+	 * space.  Because of this we have to have a omap_gem_set_sync_object()
+	 * API to allow replacement of the syncobj after it has (potentially)
+	 * already been allocated.  A bit ugly but I haven't thought of a
+	 * better alternative.
+	 */
+	struct {
+		uint32_t write_pending;
+		uint32_t write_complete;
+		uint32_t read_pending;
+		uint32_t read_complete;
+	} *sync;
+};
+
+static int get_pages(struct drm_gem_object *obj, struct page ***pages);
+static uint64_t mmap_offset(struct drm_gem_object *obj);
+
+/* To deal with userspace mmap'ings of 2d tiled buffers, which (a) are
+ * not necessarily pinned in TILER all the time, and (b) when they are
+ * they are not necessarily page aligned, we reserve one or more small
+ * regions in each of the 2d containers to use as a user-GART where we
+ * can create a second page-aligned mapping of parts of the buffer
+ * being accessed from userspace.
+ *
+ * Note that we could optimize slightly when we know that multiple
+ * tiler containers are backed by the same PAT.. but I'll leave that
+ * for later..
+ */
+#define NUM_USERGART_ENTRIES 2
+struct usergart_entry {
+	struct tiler_block *block;	/* the reserved tiler block */
+	dma_addr_t paddr;
+	struct drm_gem_object *obj;	/* the current pinned obj */
+	pgoff_t obj_pgoff;		/* page offset of obj currently
+					   mapped in */
+};
+static struct {
+	struct usergart_entry entry[NUM_USERGART_ENTRIES];
+	int height;				/* height in rows */
+	int height_shift;		/* ilog2(height in rows) */
+	int slot_shift;			/* ilog2(width per slot) */
+	int stride_pfn;			/* stride in pages */
+	int last;				/* index of last used entry */
+} *usergart;
+
+static void evict_entry(struct drm_gem_object *obj,
+		enum tiler_fmt fmt, struct usergart_entry *entry)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int n = usergart[fmt].height;
+	size_t size = PAGE_SIZE * n;
+	loff_t off = mmap_offset(obj) +
+			(entry->obj_pgoff << PAGE_SHIFT);
+	const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE);
+
+	if (m > 1) {
+		int i;
+		/* if stride > than PAGE_SIZE then sparse mapping: */
+		for (i = n; i > 0; i--) {
+			unmap_mapping_range(obj->dev->anon_inode->i_mapping,
+					    off, PAGE_SIZE, 1);
+			off += PAGE_SIZE * m;
+		}
+	} else {
+		unmap_mapping_range(obj->dev->anon_inode->i_mapping,
+				    off, size, 1);
+	}
+
+	entry->obj = NULL;
+}
+
+/* Evict a buffer from usergart, if it is mapped there */
+static void evict(struct drm_gem_object *obj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+
+	if (omap_obj->flags & OMAP_BO_TILED) {
+		enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
+		int i;
+
+		if (!usergart)
+			return;
+
+		for (i = 0; i < NUM_USERGART_ENTRIES; i++) {
+			struct usergart_entry *entry = &usergart[fmt].entry[i];
+			if (entry->obj == obj)
+				evict_entry(obj, fmt, entry);
+		}
+	}
+}
+
+/* GEM objects can either be allocated from contiguous memory (in which
+ * case obj->filp==NULL), or w/ shmem backing (obj->filp!=NULL).  But non
+ * contiguous buffers can be remapped in TILER/DMM if they need to be
+ * contiguous... but we don't do this all the time to reduce pressure
+ * on TILER/DMM space when we know at allocation time that the buffer
+ * will need to be scanned out.
+ */
+static inline bool is_shmem(struct drm_gem_object *obj)
+{
+	return obj->filp != NULL;
+}
+
+/**
+ * shmem buffers that are mapped cached can simulate coherency via using
+ * page faulting to keep track of dirty pages
+ */
+static inline bool is_cached_coherent(struct drm_gem_object *obj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	return is_shmem(obj) &&
+		((omap_obj->flags & OMAP_BO_CACHE_MASK) == OMAP_BO_CACHED);
+}
+
+static DEFINE_SPINLOCK(sync_lock);
+
+/** ensure backing pages are allocated */
+static int omap_gem_attach_pages(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	struct page **pages;
+	int npages = obj->size >> PAGE_SHIFT;
+	int i, ret;
+	dma_addr_t *addrs;
+
+	WARN_ON(omap_obj->pages);
+
+	pages = drm_gem_get_pages(obj);
+	if (IS_ERR(pages)) {
+		dev_err(obj->dev->dev, "could not get pages: %ld\n", PTR_ERR(pages));
+		return PTR_ERR(pages);
+	}
+
+	/* for non-cached buffers, ensure the new pages are clean because
+	 * DSS, GPU, etc. are not cache coherent:
+	 */
+	if (omap_obj->flags & (OMAP_BO_WC|OMAP_BO_UNCACHED)) {
+		addrs = kmalloc(npages * sizeof(*addrs), GFP_KERNEL);
+		if (!addrs) {
+			ret = -ENOMEM;
+			goto free_pages;
+		}
+
+		for (i = 0; i < npages; i++) {
+			addrs[i] = dma_map_page(dev->dev, pages[i],
+					0, PAGE_SIZE, DMA_BIDIRECTIONAL);
+		}
+	} else {
+		addrs = kzalloc(npages * sizeof(*addrs), GFP_KERNEL);
+		if (!addrs) {
+			ret = -ENOMEM;
+			goto free_pages;
+		}
+	}
+
+	omap_obj->addrs = addrs;
+	omap_obj->pages = pages;
+
+	return 0;
+
+free_pages:
+	drm_gem_put_pages(obj, pages, true, false);
+
+	return ret;
+}
+
+/** release backing pages */
+static void omap_gem_detach_pages(struct drm_gem_object *obj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+
+	/* for non-cached buffers, ensure the new pages are clean because
+	 * DSS, GPU, etc. are not cache coherent:
+	 */
+	if (omap_obj->flags & (OMAP_BO_WC|OMAP_BO_UNCACHED)) {
+		int i, npages = obj->size >> PAGE_SHIFT;
+		for (i = 0; i < npages; i++) {
+			dma_unmap_page(obj->dev->dev, omap_obj->addrs[i],
+					PAGE_SIZE, DMA_BIDIRECTIONAL);
+		}
+	}
+
+	kfree(omap_obj->addrs);
+	omap_obj->addrs = NULL;
+
+	drm_gem_put_pages(obj, omap_obj->pages, true, false);
+	omap_obj->pages = NULL;
+}
+
+/* get buffer flags */
+uint32_t omap_gem_flags(struct drm_gem_object *obj)
+{
+	return to_omap_bo(obj)->flags;
+}
+
+/** get mmap offset */
+static uint64_t mmap_offset(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	int ret;
+	size_t size;
+
+	WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
+	/* Make it mmapable */
+	size = omap_gem_mmap_size(obj);
+	ret = drm_gem_create_mmap_offset_size(obj, size);
+	if (ret) {
+		dev_err(dev->dev, "could not allocate mmap offset\n");
+		return 0;
+	}
+
+	return drm_vma_node_offset_addr(&obj->vma_node);
+}
+
+uint64_t omap_gem_mmap_offset(struct drm_gem_object *obj)
+{
+	uint64_t offset;
+	mutex_lock(&obj->dev->struct_mutex);
+	offset = mmap_offset(obj);
+	mutex_unlock(&obj->dev->struct_mutex);
+	return offset;
+}
+
+/** get mmap size */
+size_t omap_gem_mmap_size(struct drm_gem_object *obj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	size_t size = obj->size;
+
+	if (omap_obj->flags & OMAP_BO_TILED) {
+		/* for tiled buffers, the virtual size has stride rounded up
+		 * to 4kb.. (to hide the fact that row n+1 might start 16kb or
+		 * 32kb later!).  But we don't back the entire buffer with
+		 * pages, only the valid picture part.. so need to adjust for
+		 * this in the size used to mmap and generate mmap offset
+		 */
+		size = tiler_vsize(gem2fmt(omap_obj->flags),
+				omap_obj->width, omap_obj->height);
+	}
+
+	return size;
+}
+
+/* get tiled size, returns -EINVAL if not tiled buffer */
+int omap_gem_tiled_size(struct drm_gem_object *obj, uint16_t *w, uint16_t *h)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	if (omap_obj->flags & OMAP_BO_TILED) {
+		*w = omap_obj->width;
+		*h = omap_obj->height;
+		return 0;
+	}
+	return -EINVAL;
+}
+
+/* Normal handling for the case of faulting in non-tiled buffers */
+static int fault_1d(struct drm_gem_object *obj,
+		struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	unsigned long pfn;
+	pgoff_t pgoff;
+
+	/* We don't use vmf->pgoff since that has the fake offset: */
+	pgoff = ((unsigned long)vmf->virtual_address -
+			vma->vm_start) >> PAGE_SHIFT;
+
+	if (omap_obj->pages) {
+		omap_gem_cpu_sync(obj, pgoff);
+		pfn = page_to_pfn(omap_obj->pages[pgoff]);
+	} else {
+		BUG_ON(!(omap_obj->flags & OMAP_BO_DMA));
+		pfn = (omap_obj->paddr >> PAGE_SHIFT) + pgoff;
+	}
+
+	VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
+			pfn, pfn << PAGE_SHIFT);
+
+	return vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
+}
+
+/* Special handling for the case of faulting in 2d tiled buffers */
+static int fault_2d(struct drm_gem_object *obj,
+		struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	struct usergart_entry *entry;
+	enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
+	struct page *pages[64];  /* XXX is this too much to have on stack? */
+	unsigned long pfn;
+	pgoff_t pgoff, base_pgoff;
+	void __user *vaddr;
+	int i, ret, slots;
+
+	/*
+	 * Note the height of the slot is also equal to the number of pages
+	 * that need to be mapped in to fill 4kb wide CPU page.  If the slot
+	 * height is 64, then 64 pages fill a 4kb wide by 64 row region.
+	 */
+	const int n = usergart[fmt].height;
+	const int n_shift = usergart[fmt].height_shift;
+
+	/*
+	 * If buffer width in bytes > PAGE_SIZE then the virtual stride is
+	 * rounded up to next multiple of PAGE_SIZE.. this need to be taken
+	 * into account in some of the math, so figure out virtual stride
+	 * in pages
+	 */
+	const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE);
+
+	/* We don't use vmf->pgoff since that has the fake offset: */
+	pgoff = ((unsigned long)vmf->virtual_address -
+			vma->vm_start) >> PAGE_SHIFT;
+
+	/*
+	 * Actual address we start mapping at is rounded down to previous slot
+	 * boundary in the y direction:
+	 */
+	base_pgoff = round_down(pgoff, m << n_shift);
+
+	/* figure out buffer width in slots */
+	slots = omap_obj->width >> usergart[fmt].slot_shift;
+
+	vaddr = vmf->virtual_address - ((pgoff - base_pgoff) << PAGE_SHIFT);
+
+	entry = &usergart[fmt].entry[usergart[fmt].last];
+
+	/* evict previous buffer using this usergart entry, if any: */
+	if (entry->obj)
+		evict_entry(entry->obj, fmt, entry);
+
+	entry->obj = obj;
+	entry->obj_pgoff = base_pgoff;
+
+	/* now convert base_pgoff to phys offset from virt offset: */
+	base_pgoff = (base_pgoff >> n_shift) * slots;
+
+	/* for wider-than 4k.. figure out which part of the slot-row we want: */
+	if (m > 1) {
+		int off = pgoff % m;
+		entry->obj_pgoff += off;
+		base_pgoff /= m;
+		slots = min(slots - (off << n_shift), n);
+		base_pgoff += off << n_shift;
+		vaddr += off << PAGE_SHIFT;
+	}
+
+	/*
+	 * Map in pages. Beyond the valid pixel part of the buffer, we set
+	 * pages[i] to NULL to get a dummy page mapped in.. if someone
+	 * reads/writes it they will get random/undefined content, but at
+	 * least it won't be corrupting whatever other random page used to
+	 * be mapped in, or other undefined behavior.
+	 */
+	memcpy(pages, &omap_obj->pages[base_pgoff],
+			sizeof(struct page *) * slots);
+	memset(pages + slots, 0,
+			sizeof(struct page *) * (n - slots));
+
+	ret = tiler_pin(entry->block, pages, ARRAY_SIZE(pages), 0, true);
+	if (ret) {
+		dev_err(obj->dev->dev, "failed to pin: %d\n", ret);
+		return ret;
+	}
+
+	pfn = entry->paddr >> PAGE_SHIFT;
+
+	VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
+			pfn, pfn << PAGE_SHIFT);
+
+	for (i = n; i > 0; i--) {
+		vm_insert_mixed(vma, (unsigned long)vaddr, pfn);
+		pfn += usergart[fmt].stride_pfn;
+		vaddr += PAGE_SIZE * m;
+	}
+
+	/* simple round-robin: */
+	usergart[fmt].last = (usergart[fmt].last + 1) % NUM_USERGART_ENTRIES;
+
+	return 0;
+}
+
+/**
+ * omap_gem_fault		-	pagefault handler for GEM objects
+ * @vma: the VMA of the GEM object
+ * @vmf: fault detail
+ *
+ * Invoked when a fault occurs on an mmap of a GEM managed area. GEM
+ * does most of the work for us including the actual map/unmap calls
+ * but we need to do the actual page work.
+ *
+ * The VMA was set up by GEM. In doing so it also ensured that the
+ * vma->vm_private_data points to the GEM object that is backing this
+ * mapping.
+ */
+int omap_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+	struct drm_gem_object *obj = vma->vm_private_data;
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	struct drm_device *dev = obj->dev;
+	struct page **pages;
+	int ret;
+
+	/* Make sure we don't parallel update on a fault, nor move or remove
+	 * something from beneath our feet
+	 */
+	mutex_lock(&dev->struct_mutex);
+
+	/* if a shmem backed object, make sure we have pages attached now */
+	ret = get_pages(obj, &pages);
+	if (ret)
+		goto fail;
+
+	/* where should we do corresponding put_pages().. we are mapping
+	 * the original page, rather than thru a GART, so we can't rely
+	 * on eviction to trigger this.  But munmap() or all mappings should
+	 * probably trigger put_pages()?
+	 */
+
+	if (omap_obj->flags & OMAP_BO_TILED)
+		ret = fault_2d(obj, vma, vmf);
+	else
+		ret = fault_1d(obj, vma, vmf);
+
+
+fail:
+	mutex_unlock(&dev->struct_mutex);
+	switch (ret) {
+	case 0:
+	case -ERESTARTSYS:
+	case -EINTR:
+		return VM_FAULT_NOPAGE;
+	case -ENOMEM:
+		return VM_FAULT_OOM;
+	default:
+		return VM_FAULT_SIGBUS;
+	}
+}
+
+/** We override mainly to fix up some of the vm mapping flags.. */
+int omap_gem_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	int ret;
+
+	ret = drm_gem_mmap(filp, vma);
+	if (ret) {
+		DBG("mmap failed: %d", ret);
+		return ret;
+	}
+
+	return omap_gem_mmap_obj(vma->vm_private_data, vma);
+}
+
+int omap_gem_mmap_obj(struct drm_gem_object *obj,
+		struct vm_area_struct *vma)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+
+	vma->vm_flags &= ~VM_PFNMAP;
+	vma->vm_flags |= VM_MIXEDMAP;
+
+	if (omap_obj->flags & OMAP_BO_WC) {
+		vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
+	} else if (omap_obj->flags & OMAP_BO_UNCACHED) {
+		vma->vm_page_prot = pgprot_noncached(vm_get_page_prot(vma->vm_flags));
+	} else {
+		/*
+		 * We do have some private objects, at least for scanout buffers
+		 * on hardware without DMM/TILER.  But these are allocated write-
+		 * combine
+		 */
+		if (WARN_ON(!obj->filp))
+			return -EINVAL;
+
+		/*
+		 * Shunt off cached objs to shmem file so they have their own
+		 * address_space (so unmap_mapping_range does what we want,
+		 * in particular in the case of mmap'd dmabufs)
+		 */
+		fput(vma->vm_file);
+		vma->vm_pgoff = 0;
+		vma->vm_file  = get_file(obj->filp);
+
+		vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+	}
+
+	return 0;
+}
+
+
+/**
+ * omap_gem_dumb_create	-	create a dumb buffer
+ * @drm_file: our client file
+ * @dev: our device
+ * @args: the requested arguments copied from userspace
+ *
+ * Allocate a buffer suitable for use for a frame buffer of the
+ * form described by user space. Give userspace a handle by which
+ * to reference it.
+ */
+int omap_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
+		struct drm_mode_create_dumb *args)
+{
+	union omap_gem_size gsize;
+
+	args->pitch = align_pitch(0, args->width, args->bpp);
+	args->size = PAGE_ALIGN(args->pitch * args->height);
+
+	gsize = (union omap_gem_size){
+		.bytes = args->size,
+	};
+
+	return omap_gem_new_handle(dev, file, gsize,
+			OMAP_BO_SCANOUT | OMAP_BO_WC, &args->handle);
+}
+
+/**
+ * omap_gem_dumb_map	-	buffer mapping for dumb interface
+ * @file: our drm client file
+ * @dev: drm device
+ * @handle: GEM handle to the object (from dumb_create)
+ *
+ * Do the necessary setup to allow the mapping of the frame buffer
+ * into user memory. We don't have to do much here at the moment.
+ */
+int omap_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
+		uint32_t handle, uint64_t *offset)
+{
+	struct drm_gem_object *obj;
+	int ret = 0;
+
+	/* GEM does all our handle to object mapping */
+	obj = drm_gem_object_lookup(dev, file, handle);
+	if (obj == NULL) {
+		ret = -ENOENT;
+		goto fail;
+	}
+
+	*offset = omap_gem_mmap_offset(obj);
+
+	drm_gem_object_unreference_unlocked(obj);
+
+fail:
+	return ret;
+}
+
+/* Set scrolling position.  This allows us to implement fast scrolling
+ * for console.
+ *
+ * Call only from non-atomic contexts.
+ */
+int omap_gem_roll(struct drm_gem_object *obj, uint32_t roll)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	uint32_t npages = obj->size >> PAGE_SHIFT;
+	int ret = 0;
+
+	if (roll > npages) {
+		dev_err(obj->dev->dev, "invalid roll: %d\n", roll);
+		return -EINVAL;
+	}
+
+	omap_obj->roll = roll;
+
+	mutex_lock(&obj->dev->struct_mutex);
+
+	/* if we aren't mapped yet, we don't need to do anything */
+	if (omap_obj->block) {
+		struct page **pages;
+		ret = get_pages(obj, &pages);
+		if (ret)
+			goto fail;
+		ret = tiler_pin(omap_obj->block, pages, npages, roll, true);
+		if (ret)
+			dev_err(obj->dev->dev, "could not repin: %d\n", ret);
+	}
+
+fail:
+	mutex_unlock(&obj->dev->struct_mutex);
+
+	return ret;
+}
+
+/* Sync the buffer for CPU access.. note pages should already be
+ * attached, ie. omap_gem_get_pages()
+ */
+void omap_gem_cpu_sync(struct drm_gem_object *obj, int pgoff)
+{
+	struct drm_device *dev = obj->dev;
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+
+	if (is_cached_coherent(obj) && omap_obj->addrs[pgoff]) {
+		dma_unmap_page(dev->dev, omap_obj->addrs[pgoff],
+				PAGE_SIZE, DMA_BIDIRECTIONAL);
+		omap_obj->addrs[pgoff] = 0;
+	}
+}
+
+/* sync the buffer for DMA access */
+void omap_gem_dma_sync(struct drm_gem_object *obj,
+		enum dma_data_direction dir)
+{
+	struct drm_device *dev = obj->dev;
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+
+	if (is_cached_coherent(obj)) {
+		int i, npages = obj->size >> PAGE_SHIFT;
+		struct page **pages = omap_obj->pages;
+		bool dirty = false;
+
+		for (i = 0; i < npages; i++) {
+			if (!omap_obj->addrs[i]) {
+				omap_obj->addrs[i] = dma_map_page(dev->dev, pages[i], 0,
+						PAGE_SIZE, DMA_BIDIRECTIONAL);
+				dirty = true;
+			}
+		}
+
+		if (dirty) {
+			unmap_mapping_range(obj->filp->f_mapping, 0,
+					omap_gem_mmap_size(obj), 1);
+		}
+	}
+}
+
+/* Get physical address for DMA.. if 'remap' is true, and the buffer is not
+ * already contiguous, remap it to pin in physically contiguous memory.. (ie.
+ * map in TILER)
+ */
+int omap_gem_get_paddr(struct drm_gem_object *obj,
+		dma_addr_t *paddr, bool remap)
+{
+	struct omap_drm_private *priv = obj->dev->dev_private;
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = 0;
+
+	mutex_lock(&obj->dev->struct_mutex);
+
+	if (remap && is_shmem(obj) && priv->has_dmm) {
+		if (omap_obj->paddr_cnt == 0) {
+			struct page **pages;
+			uint32_t npages = obj->size >> PAGE_SHIFT;
+			enum tiler_fmt fmt = gem2fmt(omap_obj->flags);
+			struct tiler_block *block;
+
+			BUG_ON(omap_obj->block);
+
+			ret = get_pages(obj, &pages);
+			if (ret)
+				goto fail;
+
+			if (omap_obj->flags & OMAP_BO_TILED) {
+				block = tiler_reserve_2d(fmt,
+						omap_obj->width,
+						omap_obj->height, 0);
+			} else {
+				block = tiler_reserve_1d(obj->size);
+			}
+
+			if (IS_ERR(block)) {
+				ret = PTR_ERR(block);
+				dev_err(obj->dev->dev,
+					"could not remap: %d (%d)\n", ret, fmt);
+				goto fail;
+			}
+
+			/* TODO: enable async refill.. */
+			ret = tiler_pin(block, pages, npages,
+					omap_obj->roll, true);
+			if (ret) {
+				tiler_release(block);
+				dev_err(obj->dev->dev,
+						"could not pin: %d\n", ret);
+				goto fail;
+			}
+
+			omap_obj->paddr = tiler_ssptr(block);
+			omap_obj->block = block;
+
+			DBG("got paddr: %pad", &omap_obj->paddr);
+		}
+
+		omap_obj->paddr_cnt++;
+
+		*paddr = omap_obj->paddr;
+	} else if (omap_obj->flags & OMAP_BO_DMA) {
+		*paddr = omap_obj->paddr;
+	} else {
+		ret = -EINVAL;
+		goto fail;
+	}
+
+fail:
+	mutex_unlock(&obj->dev->struct_mutex);
+
+	return ret;
+}
+
+/* Release physical address, when DMA is no longer being performed.. this
+ * could potentially unpin and unmap buffers from TILER
+ */
+int omap_gem_put_paddr(struct drm_gem_object *obj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = 0;
+
+	mutex_lock(&obj->dev->struct_mutex);
+	if (omap_obj->paddr_cnt > 0) {
+		omap_obj->paddr_cnt--;
+		if (omap_obj->paddr_cnt == 0) {
+			ret = tiler_unpin(omap_obj->block);
+			if (ret) {
+				dev_err(obj->dev->dev,
+					"could not unpin pages: %d\n", ret);
+				goto fail;
+			}
+			ret = tiler_release(omap_obj->block);
+			if (ret) {
+				dev_err(obj->dev->dev,
+					"could not release unmap: %d\n", ret);
+			}
+			omap_obj->paddr = 0;
+			omap_obj->block = NULL;
+		}
+	}
+fail:
+	mutex_unlock(&obj->dev->struct_mutex);
+	return ret;
+}
+
+/* Get rotated scanout address (only valid if already pinned), at the
+ * specified orientation and x,y offset from top-left corner of buffer
+ * (only valid for tiled 2d buffers)
+ */
+int omap_gem_rotated_paddr(struct drm_gem_object *obj, uint32_t orient,
+		int x, int y, dma_addr_t *paddr)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = -EINVAL;
+
+	mutex_lock(&obj->dev->struct_mutex);
+	if ((omap_obj->paddr_cnt > 0) && omap_obj->block &&
+			(omap_obj->flags & OMAP_BO_TILED)) {
+		*paddr = tiler_tsptr(omap_obj->block, orient, x, y);
+		ret = 0;
+	}
+	mutex_unlock(&obj->dev->struct_mutex);
+	return ret;
+}
+
+/* Get tiler stride for the buffer (only valid for 2d tiled buffers) */
+int omap_gem_tiled_stride(struct drm_gem_object *obj, uint32_t orient)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = -EINVAL;
+	if (omap_obj->flags & OMAP_BO_TILED)
+		ret = tiler_stride(gem2fmt(omap_obj->flags), orient);
+	return ret;
+}
+
+/* acquire pages when needed (for example, for DMA where physically
+ * contiguous buffer is not required
+ */
+static int get_pages(struct drm_gem_object *obj, struct page ***pages)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = 0;
+
+	if (is_shmem(obj) && !omap_obj->pages) {
+		ret = omap_gem_attach_pages(obj);
+		if (ret) {
+			dev_err(obj->dev->dev, "could not attach pages\n");
+			return ret;
+		}
+	}
+
+	/* TODO: even phys-contig.. we should have a list of pages? */
+	*pages = omap_obj->pages;
+
+	return 0;
+}
+
+/* if !remap, and we don't have pages backing, then fail, rather than
+ * increasing the pin count (which we don't really do yet anyways,
+ * because we don't support swapping pages back out).  And 'remap'
+ * might not be quite the right name, but I wanted to keep it working
+ * similarly to omap_gem_get_paddr().  Note though that mutex is not
+ * aquired if !remap (because this can be called in atomic ctxt),
+ * but probably omap_gem_get_paddr() should be changed to work in the
+ * same way.  If !remap, a matching omap_gem_put_pages() call is not
+ * required (and should not be made).
+ */
+int omap_gem_get_pages(struct drm_gem_object *obj, struct page ***pages,
+		bool remap)
+{
+	int ret;
+	if (!remap) {
+		struct omap_gem_object *omap_obj = to_omap_bo(obj);
+		if (!omap_obj->pages)
+			return -ENOMEM;
+		*pages = omap_obj->pages;
+		return 0;
+	}
+	mutex_lock(&obj->dev->struct_mutex);
+	ret = get_pages(obj, pages);
+	mutex_unlock(&obj->dev->struct_mutex);
+	return ret;
+}
+
+/* release pages when DMA no longer being performed */
+int omap_gem_put_pages(struct drm_gem_object *obj)
+{
+	/* do something here if we dynamically attach/detach pages.. at
+	 * least they would no longer need to be pinned if everyone has
+	 * released the pages..
+	 */
+	return 0;
+}
+
+/* Get kernel virtual address for CPU access.. this more or less only
+ * exists for omap_fbdev.  This should be called with struct_mutex
+ * held.
+ */
+void *omap_gem_vaddr(struct drm_gem_object *obj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
+	if (!omap_obj->vaddr) {
+		struct page **pages;
+		int ret = get_pages(obj, &pages);
+		if (ret)
+			return ERR_PTR(ret);
+		omap_obj->vaddr = vmap(pages, obj->size >> PAGE_SHIFT,
+				VM_MAP, pgprot_writecombine(PAGE_KERNEL));
+	}
+	return omap_obj->vaddr;
+}
+
+#ifdef CONFIG_PM
+/* re-pin objects in DMM in resume path: */
+int omap_gem_resume(struct device *dev)
+{
+	struct drm_device *drm_dev = dev_get_drvdata(dev);
+	struct omap_drm_private *priv = drm_dev->dev_private;
+	struct omap_gem_object *omap_obj;
+	int ret = 0;
+
+	list_for_each_entry(omap_obj, &priv->obj_list, mm_list) {
+		if (omap_obj->block) {
+			struct drm_gem_object *obj = &omap_obj->base;
+			uint32_t npages = obj->size >> PAGE_SHIFT;
+			WARN_ON(!omap_obj->pages);  /* this can't happen */
+			ret = tiler_pin(omap_obj->block,
+					omap_obj->pages, npages,
+					omap_obj->roll, true);
+			if (ret) {
+				dev_err(dev, "could not repin: %d\n", ret);
+				return ret;
+			}
+		}
+	}
+
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_DEBUG_FS
+void omap_gem_describe(struct drm_gem_object *obj, struct seq_file *m)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	uint64_t off;
+
+	off = drm_vma_node_start(&obj->vma_node);
+
+	seq_printf(m, "%08x: %2d (%2d) %08llx %pad (%2d) %p %4d",
+			omap_obj->flags, obj->name, obj->refcount.refcount.counter,
+			off, &omap_obj->paddr, omap_obj->paddr_cnt,
+			omap_obj->vaddr, omap_obj->roll);
+
+	if (omap_obj->flags & OMAP_BO_TILED) {
+		seq_printf(m, " %dx%d", omap_obj->width, omap_obj->height);
+		if (omap_obj->block) {
+			struct tcm_area *area = &omap_obj->block->area;
+			seq_printf(m, " (%dx%d, %dx%d)",
+					area->p0.x, area->p0.y,
+					area->p1.x, area->p1.y);
+		}
+	} else {
+		seq_printf(m, " %d", obj->size);
+	}
+
+	seq_printf(m, "\n");
+}
+
+void omap_gem_describe_objects(struct list_head *list, struct seq_file *m)
+{
+	struct omap_gem_object *omap_obj;
+	int count = 0;
+	size_t size = 0;
+
+	list_for_each_entry(omap_obj, list, mm_list) {
+		struct drm_gem_object *obj = &omap_obj->base;
+		seq_printf(m, "   ");
+		omap_gem_describe(obj, m);
+		count++;
+		size += obj->size;
+	}
+
+	seq_printf(m, "Total %d objects, %zu bytes\n", count, size);
+}
+#endif
+
+/* Buffer Synchronization:
+ */
+
+struct omap_gem_sync_waiter {
+	struct list_head list;
+	struct omap_gem_object *omap_obj;
+	enum omap_gem_op op;
+	uint32_t read_target, write_target;
+	/* notify called w/ sync_lock held */
+	void (*notify)(void *arg);
+	void *arg;
+};
+
+/* list of omap_gem_sync_waiter.. the notify fxn gets called back when
+ * the read and/or write target count is achieved which can call a user
+ * callback (ex. to kick 3d and/or 2d), wakeup blocked task (prep for
+ * cpu access), etc.
+ */
+static LIST_HEAD(waiters);
+
+static inline bool is_waiting(struct omap_gem_sync_waiter *waiter)
+{
+	struct omap_gem_object *omap_obj = waiter->omap_obj;
+	if ((waiter->op & OMAP_GEM_READ) &&
+			(omap_obj->sync->write_complete < waiter->write_target))
+		return true;
+	if ((waiter->op & OMAP_GEM_WRITE) &&
+			(omap_obj->sync->read_complete < waiter->read_target))
+		return true;
+	return false;
+}
+
+/* macro for sync debug.. */
+#define SYNCDBG 0
+#define SYNC(fmt, ...) do { if (SYNCDBG) \
+		printk(KERN_ERR "%s:%d: "fmt"\n", \
+				__func__, __LINE__, ##__VA_ARGS__); \
+	} while (0)
+
+
+static void sync_op_update(void)
+{
+	struct omap_gem_sync_waiter *waiter, *n;
+	list_for_each_entry_safe(waiter, n, &waiters, list) {
+		if (!is_waiting(waiter)) {
+			list_del(&waiter->list);
+			SYNC("notify: %p", waiter);
+			waiter->notify(waiter->arg);
+			kfree(waiter);
+		}
+	}
+}
+
+static inline int sync_op(struct drm_gem_object *obj,
+		enum omap_gem_op op, bool start)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = 0;
+
+	spin_lock(&sync_lock);
+
+	if (!omap_obj->sync) {
+		omap_obj->sync = kzalloc(sizeof(*omap_obj->sync), GFP_ATOMIC);
+		if (!omap_obj->sync) {
+			ret = -ENOMEM;
+			goto unlock;
+		}
+	}
+
+	if (start) {
+		if (op & OMAP_GEM_READ)
+			omap_obj->sync->read_pending++;
+		if (op & OMAP_GEM_WRITE)
+			omap_obj->sync->write_pending++;
+	} else {
+		if (op & OMAP_GEM_READ)
+			omap_obj->sync->read_complete++;
+		if (op & OMAP_GEM_WRITE)
+			omap_obj->sync->write_complete++;
+		sync_op_update();
+	}
+
+unlock:
+	spin_unlock(&sync_lock);
+
+	return ret;
+}
+
+/* it is a bit lame to handle updates in this sort of polling way, but
+ * in case of PVR, the GPU can directly update read/write complete
+ * values, and not really tell us which ones it updated.. this also
+ * means that sync_lock is not quite sufficient.  So we'll need to
+ * do something a bit better when it comes time to add support for
+ * separate 2d hw..
+ */
+void omap_gem_op_update(void)
+{
+	spin_lock(&sync_lock);
+	sync_op_update();
+	spin_unlock(&sync_lock);
+}
+
+/* mark the start of read and/or write operation */
+int omap_gem_op_start(struct drm_gem_object *obj, enum omap_gem_op op)
+{
+	return sync_op(obj, op, true);
+}
+
+int omap_gem_op_finish(struct drm_gem_object *obj, enum omap_gem_op op)
+{
+	return sync_op(obj, op, false);
+}
+
+static DECLARE_WAIT_QUEUE_HEAD(sync_event);
+
+static void sync_notify(void *arg)
+{
+	struct task_struct **waiter_task = arg;
+	*waiter_task = NULL;
+	wake_up_all(&sync_event);
+}
+
+int omap_gem_op_sync(struct drm_gem_object *obj, enum omap_gem_op op)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = 0;
+	if (omap_obj->sync) {
+		struct task_struct *waiter_task = current;
+		struct omap_gem_sync_waiter *waiter =
+				kzalloc(sizeof(*waiter), GFP_KERNEL);
+
+		if (!waiter)
+			return -ENOMEM;
+
+		waiter->omap_obj = omap_obj;
+		waiter->op = op;
+		waiter->read_target = omap_obj->sync->read_pending;
+		waiter->write_target = omap_obj->sync->write_pending;
+		waiter->notify = sync_notify;
+		waiter->arg = &waiter_task;
+
+		spin_lock(&sync_lock);
+		if (is_waiting(waiter)) {
+			SYNC("waited: %p", waiter);
+			list_add_tail(&waiter->list, &waiters);
+			spin_unlock(&sync_lock);
+			ret = wait_event_interruptible(sync_event,
+					(waiter_task == NULL));
+			spin_lock(&sync_lock);
+			if (waiter_task) {
+				SYNC("interrupted: %p", waiter);
+				/* we were interrupted */
+				list_del(&waiter->list);
+				waiter_task = NULL;
+			} else {
+				/* freed in sync_op_update() */
+				waiter = NULL;
+			}
+		}
+		spin_unlock(&sync_lock);
+		kfree(waiter);
+	}
+	return ret;
+}
+
+/* call fxn(arg), either synchronously or asynchronously if the op
+ * is currently blocked..  fxn() can be called from any context
+ *
+ * (TODO for now fxn is called back from whichever context calls
+ * omap_gem_op_update().. but this could be better defined later
+ * if needed)
+ *
+ * TODO more code in common w/ _sync()..
+ */
+int omap_gem_op_async(struct drm_gem_object *obj, enum omap_gem_op op,
+		void (*fxn)(void *arg), void *arg)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	if (omap_obj->sync) {
+		struct omap_gem_sync_waiter *waiter =
+				kzalloc(sizeof(*waiter), GFP_ATOMIC);
+
+		if (!waiter)
+			return -ENOMEM;
+
+		waiter->omap_obj = omap_obj;
+		waiter->op = op;
+		waiter->read_target = omap_obj->sync->read_pending;
+		waiter->write_target = omap_obj->sync->write_pending;
+		waiter->notify = fxn;
+		waiter->arg = arg;
+
+		spin_lock(&sync_lock);
+		if (is_waiting(waiter)) {
+			SYNC("waited: %p", waiter);
+			list_add_tail(&waiter->list, &waiters);
+			spin_unlock(&sync_lock);
+			return 0;
+		}
+
+		spin_unlock(&sync_lock);
+
+		kfree(waiter);
+	}
+
+	/* no waiting.. */
+	fxn(arg);
+
+	return 0;
+}
+
+/* special API so PVR can update the buffer to use a sync-object allocated
+ * from it's sync-obj heap.  Only used for a newly allocated (from PVR's
+ * perspective) sync-object, so we overwrite the new syncobj w/ values
+ * from the already allocated syncobj (if there is one)
+ */
+int omap_gem_set_sync_object(struct drm_gem_object *obj, void *syncobj)
+{
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+	int ret = 0;
+
+	spin_lock(&sync_lock);
+
+	if ((omap_obj->flags & OMAP_BO_EXT_SYNC) && !syncobj) {
+		/* clearing a previously set syncobj */
+		syncobj = kmemdup(omap_obj->sync, sizeof(*omap_obj->sync),
+				  GFP_ATOMIC);
+		if (!syncobj) {
+			ret = -ENOMEM;
+			goto unlock;
+		}
+		omap_obj->flags &= ~OMAP_BO_EXT_SYNC;
+		omap_obj->sync = syncobj;
+	} else if (syncobj && !(omap_obj->flags & OMAP_BO_EXT_SYNC)) {
+		/* replacing an existing syncobj */
+		if (omap_obj->sync) {
+			memcpy(syncobj, omap_obj->sync, sizeof(*omap_obj->sync));
+			kfree(omap_obj->sync);
+		}
+		omap_obj->flags |= OMAP_BO_EXT_SYNC;
+		omap_obj->sync = syncobj;
+	}
+
+unlock:
+	spin_unlock(&sync_lock);
+	return ret;
+}
+
+/* don't call directly.. called from GEM core when it is time to actually
+ * free the object..
+ */
+void omap_gem_free_object(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	struct omap_drm_private *priv = dev->dev_private;
+	struct omap_gem_object *omap_obj = to_omap_bo(obj);
+
+	evict(obj);
+
+	WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+
+	spin_lock(&priv->list_lock);
+	list_del(&omap_obj->mm_list);
+	spin_unlock(&priv->list_lock);
+
+	drm_gem_free_mmap_offset(obj);
+
+	/* this means the object is still pinned.. which really should
+	 * not happen.  I think..
+	 */
+	WARN_ON(omap_obj->paddr_cnt > 0);
+
+	/* don't free externally allocated backing memory */
+	if (!(omap_obj->flags & OMAP_BO_EXT_MEM)) {
+		if (omap_obj->pages)
+			omap_gem_detach_pages(obj);
+
+		if (!is_shmem(obj)) {
+			dma_free_writecombine(dev->dev, obj->size,
+					omap_obj->vaddr, omap_obj->paddr);
+		} else if (omap_obj->vaddr) {
+			vunmap(omap_obj->vaddr);
+		}
+	}
+
+	/* don't free externally allocated syncobj */
+	if (!(omap_obj->flags & OMAP_BO_EXT_SYNC))
+		kfree(omap_obj->sync);
+
+	drm_gem_object_release(obj);
+
+	kfree(obj);
+}
+
+/* convenience method to construct a GEM buffer object, and userspace handle */
+int omap_gem_new_handle(struct drm_device *dev, struct drm_file *file,
+		union omap_gem_size gsize, uint32_t flags, uint32_t *handle)
+{
+	struct drm_gem_object *obj;
+	int ret;
+
+	obj = omap_gem_new(dev, gsize, flags);
+	if (!obj)
+		return -ENOMEM;
+
+	ret = drm_gem_handle_create(file, obj, handle);
+	if (ret) {
+		drm_gem_object_release(obj);
+		kfree(obj); /* TODO isn't there a dtor to call? just copying i915 */
+		return ret;
+	}
+
+	/* drop reference from allocate - handle holds it now */
+	drm_gem_object_unreference_unlocked(obj);
+
+	return 0;
+}
+
+/* GEM buffer object constructor */
+struct drm_gem_object *omap_gem_new(struct drm_device *dev,
+		union omap_gem_size gsize, uint32_t flags)
+{
+	struct omap_drm_private *priv = dev->dev_private;
+	struct omap_gem_object *omap_obj;
+	struct drm_gem_object *obj = NULL;
+	struct address_space *mapping;
+	size_t size;
+	int ret;
+
+	if (flags & OMAP_BO_TILED) {
+		if (!usergart) {
+			dev_err(dev->dev, "Tiled buffers require DMM\n");
+			goto fail;
+		}
+
+		/* tiled buffers are always shmem paged backed.. when they are
+		 * scanned out, they are remapped into DMM/TILER
+		 */
+		flags &= ~OMAP_BO_SCANOUT;
+
+		/* currently don't allow cached buffers.. there is some caching
+		 * stuff that needs to be handled better
+		 */
+		flags &= ~(OMAP_BO_CACHED|OMAP_BO_WC|OMAP_BO_UNCACHED);
+		flags |= tiler_get_cpu_cache_flags();
+
+		/* align dimensions to slot boundaries... */
+		tiler_align(gem2fmt(flags),
+				&gsize.tiled.width, &gsize.tiled.height);
+
+		/* ...and calculate size based on aligned dimensions */
+		size = tiler_size(gem2fmt(flags),
+				gsize.tiled.width, gsize.tiled.height);
+	} else {
+		size = PAGE_ALIGN(gsize.bytes);
+	}
+
+	omap_obj = kzalloc(sizeof(*omap_obj), GFP_KERNEL);
+	if (!omap_obj)
+		goto fail;
+
+	spin_lock(&priv->list_lock);
+	list_add(&omap_obj->mm_list, &priv->obj_list);
+	spin_unlock(&priv->list_lock);
+
+	obj = &omap_obj->base;
+
+	if ((flags & OMAP_BO_SCANOUT) && !priv->has_dmm) {
+		/* attempt to allocate contiguous memory if we don't
+		 * have DMM for remappign discontiguous buffers
+		 */
+		omap_obj->vaddr =  dma_alloc_writecombine(dev->dev, size,
+				&omap_obj->paddr, GFP_KERNEL);
+		if (omap_obj->vaddr)
+			flags |= OMAP_BO_DMA;
+
+	}
+
+	omap_obj->flags = flags;
+
+	if (flags & OMAP_BO_TILED) {
+		omap_obj->width = gsize.tiled.width;
+		omap_obj->height = gsize.tiled.height;
+	}
+
+	if (flags & (OMAP_BO_DMA|OMAP_BO_EXT_MEM)) {
+		drm_gem_private_object_init(dev, obj, size);
+	} else {
+		ret = drm_gem_object_init(dev, obj, size);
+		if (ret)
+			goto fail;
+
+		mapping = file_inode(obj->filp)->i_mapping;
+		mapping_set_gfp_mask(mapping, GFP_USER | __GFP_DMA32);
+	}
+
+	return obj;
+
+fail:
+	if (obj)
+		omap_gem_free_object(obj);
+
+	return NULL;
+}
+
+/* init/cleanup.. if DMM is used, we need to set some stuff up.. */
+void omap_gem_init(struct drm_device *dev)
+{
+	struct omap_drm_private *priv = dev->dev_private;
+	const enum tiler_fmt fmts[] = {
+			TILFMT_8BIT, TILFMT_16BIT, TILFMT_32BIT
+	};
+	int i, j;
+
+	if (!dmm_is_available()) {
+		/* DMM only supported on OMAP4 and later, so this isn't fatal */
+		dev_warn(dev->dev, "DMM not available, disable DMM support\n");
+		return;
+	}
+
+	usergart = kcalloc(3, sizeof(*usergart), GFP_KERNEL);
+	if (!usergart)
+		return;
+
+	/* reserve 4k aligned/wide regions for userspace mappings: */
+	for (i = 0; i < ARRAY_SIZE(fmts); i++) {
+		uint16_t h = 1, w = PAGE_SIZE >> i;
+		tiler_align(fmts[i], &w, &h);
+		/* note: since each region is 1 4kb page wide, and minimum
+		 * number of rows, the height ends up being the same as the
+		 * # of pages in the region
+		 */
+		usergart[i].height = h;
+		usergart[i].height_shift = ilog2(h);
+		usergart[i].stride_pfn = tiler_stride(fmts[i], 0) >> PAGE_SHIFT;
+		usergart[i].slot_shift = ilog2((PAGE_SIZE / h) >> i);
+		for (j = 0; j < NUM_USERGART_ENTRIES; j++) {
+			struct usergart_entry *entry = &usergart[i].entry[j];
+			struct tiler_block *block =
+					tiler_reserve_2d(fmts[i], w, h,
+							PAGE_SIZE);
+			if (IS_ERR(block)) {
+				dev_err(dev->dev,
+						"reserve failed: %d, %d, %ld\n",
+						i, j, PTR_ERR(block));
+				return;
+			}
+			entry->paddr = tiler_ssptr(block);
+			entry->block = block;
+
+			DBG("%d:%d: %dx%d: paddr=%pad stride=%d", i, j, w, h,
+					&entry->paddr,
+					usergart[i].stride_pfn << PAGE_SHIFT);
+		}
+	}
+
+	priv->has_dmm = true;
+}
+
+void omap_gem_deinit(struct drm_device *dev)
+{
+	/* I believe we can rely on there being no more outstanding GEM
+	 * objects which could depend on usergart/dmm at this point.
+	 */
+	kfree(usergart);
+}