drivers/gpu/drm/radeon/radeon_ttm.c

/*
 * Copyright 2009 Jerome Glisse.
 * 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 */
/*
 * Authors:
 *    Jerome Glisse <glisse@freedesktop.org>
 *    Thomas Hellstrom <thomas-at-tungstengraphics-dot-com>
 *    Dave Airlie
 */

#include <linux/dma-mapping.h>
#include <linux/pagemap.h>
#include <linux/pci.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/swap.h>

#include <drm/drm_device.h>
#include <drm/drm_file.h>
#include <drm/drm_prime.h>
#include <drm/radeon_drm.h>
#include <drm/ttm/ttm_bo.h>
#include <drm/ttm/ttm_placement.h>
#include <drm/ttm/ttm_range_manager.h>
#include <drm/ttm/ttm_tt.h>

#include "radeon_reg.h"
#include "radeon.h"
#include "radeon_ttm.h"

static void radeon_ttm_debugfs_init(struct radeon_device *rdev);

static int radeon_ttm_tt_bind(struct ttm_device *bdev, struct ttm_tt *ttm,
			      struct ttm_resource *bo_mem);
static void radeon_ttm_tt_unbind(struct ttm_device *bdev, struct ttm_tt *ttm);

struct radeon_device *radeon_get_rdev(struct ttm_device *bdev)
{
	struct radeon_mman *mman;
	struct radeon_device *rdev;

	mman = container_of(bdev, struct radeon_mman, bdev);
	rdev = container_of(mman, struct radeon_device, mman);
	return rdev;
}

static int radeon_ttm_init_vram(struct radeon_device *rdev)
{
	return ttm_range_man_init(&rdev->mman.bdev, TTM_PL_VRAM,
				  false, rdev->mc.real_vram_size >> PAGE_SHIFT);
}

static int radeon_ttm_init_gtt(struct radeon_device *rdev)
{
	return ttm_range_man_init(&rdev->mman.bdev, TTM_PL_TT,
				  true, rdev->mc.gtt_size >> PAGE_SHIFT);
}

static void radeon_evict_flags(struct ttm_buffer_object *bo,
				struct ttm_placement *placement)
{
	static const struct ttm_place placements = {
		.fpfn = 0,
		.lpfn = 0,
		.mem_type = TTM_PL_SYSTEM,
		.flags = 0
	};

	struct radeon_bo *rbo;

	if (!radeon_ttm_bo_is_radeon_bo(bo)) {
		placement->placement = &placements;
		placement->num_placement = 1;
		return;
	}
	rbo = container_of(bo, struct radeon_bo, tbo);
	switch (bo->resource->mem_type) {
	case TTM_PL_VRAM:
		if (rbo->rdev->ring[radeon_copy_ring_index(rbo->rdev)].ready == false)
			radeon_ttm_placement_from_domain(rbo, RADEON_GEM_DOMAIN_CPU);
		else if (rbo->rdev->mc.visible_vram_size < rbo->rdev->mc.real_vram_size &&
			 bo->resource->start < (rbo->rdev->mc.visible_vram_size >> PAGE_SHIFT)) {
			unsigned fpfn = rbo->rdev->mc.visible_vram_size >> PAGE_SHIFT;
			int i;

			/* Try evicting to the CPU inaccessible part of VRAM
			 * first, but only set GTT as busy placement, so this
			 * BO will be evicted to GTT rather than causing other
			 * BOs to be evicted from VRAM
			 */
			radeon_ttm_placement_from_domain(rbo, RADEON_GEM_DOMAIN_VRAM |
							 RADEON_GEM_DOMAIN_GTT);
			for (i = 0; i < rbo->placement.num_placement; i++) {
				if (rbo->placements[i].mem_type == TTM_PL_VRAM) {
					if (rbo->placements[i].fpfn < fpfn)
						rbo->placements[i].fpfn = fpfn;
					rbo->placements[0].flags |= TTM_PL_FLAG_DESIRED;
				}
			}
		} else
			radeon_ttm_placement_from_domain(rbo, RADEON_GEM_DOMAIN_GTT);
		break;
	case TTM_PL_TT:
	default:
		radeon_ttm_placement_from_domain(rbo, RADEON_GEM_DOMAIN_CPU);
	}
	*placement = rbo->placement;
}

static int radeon_move_blit(struct ttm_buffer_object *bo,
			bool evict,
			struct ttm_resource *new_mem,
			struct ttm_resource *old_mem)
{
	struct radeon_device *rdev;
	uint64_t old_start, new_start;
	struct radeon_fence *fence;
	unsigned num_pages;
	int r, ridx;

	rdev = radeon_get_rdev(bo->bdev);
	ridx = radeon_copy_ring_index(rdev);
	old_start = (u64)old_mem->start << PAGE_SHIFT;
	new_start = (u64)new_mem->start << PAGE_SHIFT;

	switch (old_mem->mem_type) {
	case TTM_PL_VRAM:
		old_start += rdev->mc.vram_start;
		break;
	case TTM_PL_TT:
		old_start += rdev->mc.gtt_start;
		break;
	default:
		DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
		return -EINVAL;
	}
	switch (new_mem->mem_type) {
	case TTM_PL_VRAM:
		new_start += rdev->mc.vram_start;
		break;
	case TTM_PL_TT:
		new_start += rdev->mc.gtt_start;
		break;
	default:
		DRM_ERROR("Unknown placement %d\n", old_mem->mem_type);
		return -EINVAL;
	}
	if (!rdev->ring[ridx].ready) {
		DRM_ERROR("Trying to move memory with ring turned off.\n");
		return -EINVAL;
	}

	BUILD_BUG_ON((PAGE_SIZE % RADEON_GPU_PAGE_SIZE) != 0);

	num_pages = PFN_UP(new_mem->size) * (PAGE_SIZE / RADEON_GPU_PAGE_SIZE);
	fence = radeon_copy(rdev, old_start, new_start, num_pages, bo->base.resv);
	if (IS_ERR(fence))
		return PTR_ERR(fence);

	r = ttm_bo_move_accel_cleanup(bo, &fence->base, evict, false, new_mem);
	radeon_fence_unref(&fence);
	return r;
}

static int radeon_bo_move(struct ttm_buffer_object *bo, bool evict,
			  struct ttm_operation_ctx *ctx,
			  struct ttm_resource *new_mem,
			  struct ttm_place *hop)
{
	struct ttm_resource *old_mem = bo->resource;
	struct radeon_device *rdev;
	int r;

	if (new_mem->mem_type == TTM_PL_TT) {
		r = radeon_ttm_tt_bind(bo->bdev, bo->ttm, new_mem);
		if (r)
			return r;
	}

	r = ttm_bo_wait_ctx(bo, ctx);
	if (r)
		return r;

	rdev = radeon_get_rdev(bo->bdev);
	if (!old_mem || (old_mem->mem_type == TTM_PL_SYSTEM &&
			 bo->ttm == NULL)) {
		ttm_bo_move_null(bo, new_mem);
		goto out;
	}
	if (old_mem->mem_type == TTM_PL_SYSTEM &&
	    new_mem->mem_type == TTM_PL_TT) {
		ttm_bo_move_null(bo, new_mem);
		goto out;
	}

	if (old_mem->mem_type == TTM_PL_TT &&
	    new_mem->mem_type == TTM_PL_SYSTEM) {
		radeon_ttm_tt_unbind(bo->bdev, bo->ttm);
		ttm_resource_free(bo, &bo->resource);
		ttm_bo_assign_mem(bo, new_mem);
		goto out;
	}
	if (rdev->ring[radeon_copy_ring_index(rdev)].ready &&
	    rdev->asic->copy.copy != NULL) {
		if ((old_mem->mem_type == TTM_PL_SYSTEM &&
		     new_mem->mem_type == TTM_PL_VRAM) ||
		    (old_mem->mem_type == TTM_PL_VRAM &&
		     new_mem->mem_type == TTM_PL_SYSTEM)) {
			hop->fpfn = 0;
			hop->lpfn = 0;
			hop->mem_type = TTM_PL_TT;
			hop->flags = 0;
			return -EMULTIHOP;
		}

		r = radeon_move_blit(bo, evict, new_mem, old_mem);
	} else {
		r = -ENODEV;
	}

	if (r) {
		r = ttm_bo_move_memcpy(bo, ctx, new_mem);
		if (r)
			return r;
	}

out:
	/* update statistics */
	atomic64_add(bo->base.size, &rdev->num_bytes_moved);
	radeon_bo_move_notify(bo);
	return 0;
}

static int radeon_ttm_io_mem_reserve(struct ttm_device *bdev, struct ttm_resource *mem)
{
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	size_t bus_size = (size_t)mem->size;

	switch (mem->mem_type) {
	case TTM_PL_SYSTEM:
		/* system memory */
		return 0;
	case TTM_PL_TT:
#if IS_ENABLED(CONFIG_AGP)
		if (rdev->flags & RADEON_IS_AGP) {
			/* RADEON_IS_AGP is set only if AGP is active */
			mem->bus.offset = (mem->start << PAGE_SHIFT) +
				rdev->mc.agp_base;
			mem->bus.is_iomem = !rdev->agp->cant_use_aperture;
			mem->bus.caching = ttm_write_combined;
		}
#endif
		break;
	case TTM_PL_VRAM:
		mem->bus.offset = mem->start << PAGE_SHIFT;
		/* check if it's visible */
		if ((mem->bus.offset + bus_size) > rdev->mc.visible_vram_size)
			return -EINVAL;
		mem->bus.offset += rdev->mc.aper_base;
		mem->bus.is_iomem = true;
		mem->bus.caching = ttm_write_combined;
#ifdef __alpha__
		/*
		 * Alpha: use bus.addr to hold the ioremap() return,
		 * so we can modify bus.base below.
		 */
		mem->bus.addr = ioremap_wc(mem->bus.offset, bus_size);
		if (!mem->bus.addr)
			return -ENOMEM;

		/*
		 * Alpha: Use just the bus offset plus
		 * the hose/domain memory base for bus.base.
		 * It then can be used to build PTEs for VRAM
		 * access, as done in ttm_bo_vm_fault().
		 */
		mem->bus.offset = (mem->bus.offset & 0x0ffffffffUL) +
			rdev->hose->dense_mem_base;
#endif
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

/*
 * TTM backend functions.
 */
struct radeon_ttm_tt {
	struct ttm_tt		ttm;
	u64				offset;

	uint64_t			userptr;
	struct mm_struct		*usermm;
	uint32_t			userflags;
	bool bound;
};

/* prepare the sg table with the user pages */
static int radeon_ttm_tt_pin_userptr(struct ttm_device *bdev, struct ttm_tt *ttm)
{
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	struct radeon_ttm_tt *gtt = (void *)ttm;
	unsigned pinned = 0;
	int r;

	int write = !(gtt->userflags & RADEON_GEM_USERPTR_READONLY);
	enum dma_data_direction direction = write ?
		DMA_BIDIRECTIONAL : DMA_TO_DEVICE;

	if (current->mm != gtt->usermm)
		return -EPERM;

	if (gtt->userflags & RADEON_GEM_USERPTR_ANONONLY) {
		/* check that we only pin down anonymous memory
		   to prevent problems with writeback */
		unsigned long end = gtt->userptr + (u64)ttm->num_pages * PAGE_SIZE;
		struct vm_area_struct *vma;
		vma = find_vma(gtt->usermm, gtt->userptr);
		if (!vma || vma->vm_file || vma->vm_end < end)
			return -EPERM;
	}

	do {
		unsigned num_pages = ttm->num_pages - pinned;
		uint64_t userptr = gtt->userptr + pinned * PAGE_SIZE;
		struct page **pages = ttm->pages + pinned;

		r = get_user_pages(userptr, num_pages, write ? FOLL_WRITE : 0,
				   pages);
		if (r < 0)
			goto release_pages;

		pinned += r;

	} while (pinned < ttm->num_pages);

	r = sg_alloc_table_from_pages(ttm->sg, ttm->pages, ttm->num_pages, 0,
				      (u64)ttm->num_pages << PAGE_SHIFT,
				      GFP_KERNEL);
	if (r)
		goto release_sg;

	r = dma_map_sgtable(rdev->dev, ttm->sg, direction, 0);
	if (r)
		goto release_sg;

	drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address,
				       ttm->num_pages);

	return 0;

release_sg:
	kfree(ttm->sg);

release_pages:
	release_pages(ttm->pages, pinned);
	return r;
}

static void radeon_ttm_tt_unpin_userptr(struct ttm_device *bdev, struct ttm_tt *ttm)
{
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	struct radeon_ttm_tt *gtt = (void *)ttm;
	struct sg_page_iter sg_iter;

	int write = !(gtt->userflags & RADEON_GEM_USERPTR_READONLY);
	enum dma_data_direction direction = write ?
		DMA_BIDIRECTIONAL : DMA_TO_DEVICE;

	/* double check that we don't free the table twice */
	if (!ttm->sg || !ttm->sg->sgl)
		return;

	/* free the sg table and pages again */
	dma_unmap_sgtable(rdev->dev, ttm->sg, direction, 0);

	for_each_sgtable_page(ttm->sg, &sg_iter, 0) {
		struct page *page = sg_page_iter_page(&sg_iter);
		if (!(gtt->userflags & RADEON_GEM_USERPTR_READONLY))
			set_page_dirty(page);

		mark_page_accessed(page);
		put_page(page);
	}

	sg_free_table(ttm->sg);
}

static bool radeon_ttm_backend_is_bound(struct ttm_tt *ttm)
{
	struct radeon_ttm_tt *gtt = (void*)ttm;

	return (gtt->bound);
}

static int radeon_ttm_backend_bind(struct ttm_device *bdev,
				   struct ttm_tt *ttm,
				   struct ttm_resource *bo_mem)
{
	struct radeon_ttm_tt *gtt = (void*)ttm;
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	uint32_t flags = RADEON_GART_PAGE_VALID | RADEON_GART_PAGE_READ |
		RADEON_GART_PAGE_WRITE;
	int r;

	if (gtt->bound)
		return 0;

	if (gtt->userptr) {
		radeon_ttm_tt_pin_userptr(bdev, ttm);
		flags &= ~RADEON_GART_PAGE_WRITE;
	}

	gtt->offset = (unsigned long)(bo_mem->start << PAGE_SHIFT);
	if (!ttm->num_pages) {
		WARN(1, "nothing to bind %u pages for mreg %p back %p!\n",
		     ttm->num_pages, bo_mem, ttm);
	}
	if (ttm->caching == ttm_cached)
		flags |= RADEON_GART_PAGE_SNOOP;
	r = radeon_gart_bind(rdev, gtt->offset, ttm->num_pages,
			     ttm->pages, gtt->ttm.dma_address, flags);
	if (r) {
		DRM_ERROR("failed to bind %u pages at 0x%08X\n",
			  ttm->num_pages, (unsigned)gtt->offset);
		return r;
	}
	gtt->bound = true;
	return 0;
}

static void radeon_ttm_backend_unbind(struct ttm_device *bdev, struct ttm_tt *ttm)
{
	struct radeon_ttm_tt *gtt = (void *)ttm;
	struct radeon_device *rdev = radeon_get_rdev(bdev);

	if (gtt->userptr)
		radeon_ttm_tt_unpin_userptr(bdev, ttm);

	if (!gtt->bound)
		return;

	radeon_gart_unbind(rdev, gtt->offset, ttm->num_pages);

	gtt->bound = false;
}

static void radeon_ttm_backend_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
{
	struct radeon_ttm_tt *gtt = (void *)ttm;

	ttm_tt_fini(&gtt->ttm);
	kfree(gtt);
}

static struct ttm_tt *radeon_ttm_tt_create(struct ttm_buffer_object *bo,
					   uint32_t page_flags)
{
	struct radeon_ttm_tt *gtt;
	enum ttm_caching caching;
	struct radeon_bo *rbo;
#if IS_ENABLED(CONFIG_AGP)
	struct radeon_device *rdev = radeon_get_rdev(bo->bdev);

	if (rdev->flags & RADEON_IS_AGP) {
		return ttm_agp_tt_create(bo, rdev->agp->bridge, page_flags);
	}
#endif
	rbo = container_of(bo, struct radeon_bo, tbo);

	gtt = kzalloc(sizeof(struct radeon_ttm_tt), GFP_KERNEL);
	if (gtt == NULL) {
		return NULL;
	}

	if (rbo->flags & RADEON_GEM_GTT_UC)
		caching = ttm_uncached;
	else if (rbo->flags & RADEON_GEM_GTT_WC)
		caching = ttm_write_combined;
	else
		caching = ttm_cached;

	if (ttm_sg_tt_init(&gtt->ttm, bo, page_flags, caching)) {
		kfree(gtt);
		return NULL;
	}
	return &gtt->ttm;
}

static struct radeon_ttm_tt *radeon_ttm_tt_to_gtt(struct radeon_device *rdev,
						  struct ttm_tt *ttm)
{
#if IS_ENABLED(CONFIG_AGP)
	if (rdev->flags & RADEON_IS_AGP)
		return NULL;
#endif

	if (!ttm)
		return NULL;
	return container_of(ttm, struct radeon_ttm_tt, ttm);
}

static int radeon_ttm_tt_populate(struct ttm_device *bdev,
				  struct ttm_tt *ttm,
				  struct ttm_operation_ctx *ctx)
{
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	struct radeon_ttm_tt *gtt = radeon_ttm_tt_to_gtt(rdev, ttm);
	bool slave = !!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL);

	if (gtt && gtt->userptr) {
		ttm->sg = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
		if (!ttm->sg)
			return -ENOMEM;

		ttm->page_flags |= TTM_TT_FLAG_EXTERNAL;
		return 0;
	}

	if (slave && ttm->sg) {
		drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address,
					       ttm->num_pages);
		return 0;
	}

	return ttm_pool_alloc(&rdev->mman.bdev.pool, ttm, ctx);
}

static void radeon_ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
{
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	struct radeon_ttm_tt *gtt = radeon_ttm_tt_to_gtt(rdev, ttm);
	bool slave = !!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL);

	radeon_ttm_tt_unbind(bdev, ttm);

	if (gtt && gtt->userptr) {
		kfree(ttm->sg);
		ttm->page_flags &= ~TTM_TT_FLAG_EXTERNAL;
		return;
	}

	if (slave)
		return;

	return ttm_pool_free(&rdev->mman.bdev.pool, ttm);
}

int radeon_ttm_tt_set_userptr(struct radeon_device *rdev,
			      struct ttm_tt *ttm, uint64_t addr,
			      uint32_t flags)
{
	struct radeon_ttm_tt *gtt = radeon_ttm_tt_to_gtt(rdev, ttm);

	if (gtt == NULL)
		return -EINVAL;

	gtt->userptr = addr;
	gtt->usermm = current->mm;
	gtt->userflags = flags;
	return 0;
}

bool radeon_ttm_tt_is_bound(struct ttm_device *bdev,
			    struct ttm_tt *ttm)
{
#if IS_ENABLED(CONFIG_AGP)
	struct radeon_device *rdev = radeon_get_rdev(bdev);
	if (rdev->flags & RADEON_IS_AGP)
		return ttm_agp_is_bound(ttm);
#endif
	return radeon_ttm_backend_is_bound(ttm);
}

static int radeon_ttm_tt_bind(struct ttm_device *bdev,
			      struct ttm_tt *ttm,
			      struct ttm_resource *bo_mem)
{
#if IS_ENABLED(CONFIG_AGP)
	struct radeon_device *rdev = radeon_get_rdev(bdev);
#endif

	if (!bo_mem)
		return -EINVAL;
#if IS_ENABLED(CONFIG_AGP)
	if (rdev->flags & RADEON_IS_AGP)
		return ttm_agp_bind(ttm, bo_mem);
#endif

	return radeon_ttm_backend_bind(bdev, ttm, bo_mem);
}

static void radeon_ttm_tt_unbind(struct ttm_device *bdev,
				 struct ttm_tt *ttm)
{
#if IS_ENABLED(CONFIG_AGP)
	struct radeon_device *rdev = radeon_get_rdev(bdev);

	if (rdev->flags & RADEON_IS_AGP) {
		ttm_agp_unbind(ttm);
		return;
	}
#endif
	radeon_ttm_backend_unbind(bdev, ttm);
}

static void radeon_ttm_tt_destroy(struct ttm_device *bdev,
				  struct ttm_tt *ttm)
{
#if IS_ENABLED(CONFIG_AGP)
	struct radeon_device *rdev = radeon_get_rdev(bdev);

	if (rdev->flags & RADEON_IS_AGP) {
		ttm_agp_destroy(ttm);
		return;
	}
#endif
	radeon_ttm_backend_destroy(bdev, ttm);
}

bool radeon_ttm_tt_has_userptr(struct radeon_device *rdev,
			       struct ttm_tt *ttm)
{
	struct radeon_ttm_tt *gtt = radeon_ttm_tt_to_gtt(rdev, ttm);

	if (gtt == NULL)
		return false;

	return !!gtt->userptr;
}

bool radeon_ttm_tt_is_readonly(struct radeon_device *rdev,
			       struct ttm_tt *ttm)
{
	struct radeon_ttm_tt *gtt = radeon_ttm_tt_to_gtt(rdev, ttm);

	if (gtt == NULL)
		return false;

	return !!(gtt->userflags & RADEON_GEM_USERPTR_READONLY);
}

static struct ttm_device_funcs radeon_bo_driver = {
	.ttm_tt_create = &radeon_ttm_tt_create,
	.ttm_tt_populate = &radeon_ttm_tt_populate,
	.ttm_tt_unpopulate = &radeon_ttm_tt_unpopulate,
	.ttm_tt_destroy = &radeon_ttm_tt_destroy,
	.eviction_valuable = ttm_bo_eviction_valuable,
	.evict_flags = &radeon_evict_flags,
	.move = &radeon_bo_move,
	.io_mem_reserve = &radeon_ttm_io_mem_reserve,
};

int radeon_ttm_init(struct radeon_device *rdev)
{
	int r;

	/* No others user of address space so set it to 0 */
	r = ttm_device_init(&rdev->mman.bdev, &radeon_bo_driver, rdev->dev,
			       rdev->ddev->anon_inode->i_mapping,
			       rdev->ddev->vma_offset_manager,
			       rdev->need_swiotlb,
			       dma_addressing_limited(&rdev->pdev->dev));
	if (r) {
		DRM_ERROR("failed initializing buffer object driver(%d).\n", r);
		return r;
	}
	rdev->mman.initialized = true;

	r = radeon_ttm_init_vram(rdev);
	if (r) {
		DRM_ERROR("Failed initializing VRAM heap.\n");
		return r;
	}
	/* Change the size here instead of the init above so only lpfn is affected */
	radeon_ttm_set_active_vram_size(rdev, rdev->mc.visible_vram_size);

	r = radeon_bo_create(rdev, 256 * 1024, PAGE_SIZE, true,
			     RADEON_GEM_DOMAIN_VRAM, 0, NULL,
			     NULL, &rdev->stolen_vga_memory);
	if (r) {
		return r;
	}
	r = radeon_bo_reserve(rdev->stolen_vga_memory, false);
	if (r)
		return r;
	r = radeon_bo_pin(rdev->stolen_vga_memory, RADEON_GEM_DOMAIN_VRAM, NULL);
	radeon_bo_unreserve(rdev->stolen_vga_memory);
	if (r) {
		radeon_bo_unref(&rdev->stolen_vga_memory);
		return r;
	}
	DRM_INFO("radeon: %uM of VRAM memory ready\n",
		 (unsigned) (rdev->mc.real_vram_size / (1024 * 1024)));

	r = radeon_ttm_init_gtt(rdev);
	if (r) {
		DRM_ERROR("Failed initializing GTT heap.\n");
		return r;
	}
	DRM_INFO("radeon: %uM of GTT memory ready.\n",
		 (unsigned)(rdev->mc.gtt_size / (1024 * 1024)));

	radeon_ttm_debugfs_init(rdev);

	return 0;
}

void radeon_ttm_fini(struct radeon_device *rdev)
{
	int r;

	if (!rdev->mman.initialized)
		return;

	if (rdev->stolen_vga_memory) {
		r = radeon_bo_reserve(rdev->stolen_vga_memory, false);
		if (r == 0) {
			radeon_bo_unpin(rdev->stolen_vga_memory);
			radeon_bo_unreserve(rdev->stolen_vga_memory);
		}
		radeon_bo_unref(&rdev->stolen_vga_memory);
	}
	ttm_range_man_fini(&rdev->mman.bdev, TTM_PL_VRAM);
	ttm_range_man_fini(&rdev->mman.bdev, TTM_PL_TT);
	ttm_device_fini(&rdev->mman.bdev);
	radeon_gart_fini(rdev);
	rdev->mman.initialized = false;
	DRM_INFO("radeon: ttm finalized\n");
}

/* this should only be called at bootup or when userspace
 * isn't running */
void radeon_ttm_set_active_vram_size(struct radeon_device *rdev, u64 size)
{
	struct ttm_resource_manager *man;

	if (!rdev->mman.initialized)
		return;

	man = ttm_manager_type(&rdev->mman.bdev, TTM_PL_VRAM);
	/* this just adjusts TTM size idea, which sets lpfn to the correct value */
	man->size = size >> PAGE_SHIFT;
}

#if defined(CONFIG_DEBUG_FS)

static int radeon_ttm_page_pool_show(struct seq_file *m, void *data)
{
	struct radeon_device *rdev = m->private;

	return ttm_pool_debugfs(&rdev->mman.bdev.pool, m);
}

DEFINE_SHOW_ATTRIBUTE(radeon_ttm_page_pool);

static int radeon_ttm_vram_open(struct inode *inode, struct file *filep)
{
	struct radeon_device *rdev = inode->i_private;
	i_size_write(inode, rdev->mc.mc_vram_size);
	filep->private_data = inode->i_private;
	return 0;
}

static ssize_t radeon_ttm_vram_read(struct file *f, char __user *buf,
				    size_t size, loff_t *pos)
{
	struct radeon_device *rdev = f->private_data;
	ssize_t result = 0;
	int r;

	if (size & 0x3 || *pos & 0x3)
		return -EINVAL;

	while (size) {
		unsigned long flags;
		uint32_t value;

		if (*pos >= rdev->mc.mc_vram_size)
			return result;

		spin_lock_irqsave(&rdev->mmio_idx_lock, flags);
		WREG32(RADEON_MM_INDEX, ((uint32_t)*pos) | 0x80000000);
		if (rdev->family >= CHIP_CEDAR)
			WREG32(EVERGREEN_MM_INDEX_HI, *pos >> 31);
		value = RREG32(RADEON_MM_DATA);
		spin_unlock_irqrestore(&rdev->mmio_idx_lock, flags);

		r = put_user(value, (uint32_t __user *)buf);
		if (r)
			return r;

		result += 4;
		buf += 4;
		*pos += 4;
		size -= 4;
	}

	return result;
}

static const struct file_operations radeon_ttm_vram_fops = {
	.owner = THIS_MODULE,
	.open = radeon_ttm_vram_open,
	.read = radeon_ttm_vram_read,
	.llseek = default_llseek
};

static int radeon_ttm_gtt_open(struct inode *inode, struct file *filep)
{
	struct radeon_device *rdev = inode->i_private;
	i_size_write(inode, rdev->mc.gtt_size);
	filep->private_data = inode->i_private;
	return 0;
}

static ssize_t radeon_ttm_gtt_read(struct file *f, char __user *buf,
				   size_t size, loff_t *pos)
{
	struct radeon_device *rdev = f->private_data;
	ssize_t result = 0;
	int r;

	while (size) {
		loff_t p = *pos / PAGE_SIZE;
		unsigned off = *pos & ~PAGE_MASK;
		size_t cur_size = min_t(size_t, size, PAGE_SIZE - off);
		struct page *page;
		void *ptr;

		if (p >= rdev->gart.num_cpu_pages)
			return result;

		page = rdev->gart.pages[p];
		if (page) {
			ptr = kmap_local_page(page);
			ptr += off;

			r = copy_to_user(buf, ptr, cur_size);
			kunmap_local(ptr);
		} else
			r = clear_user(buf, cur_size);

		if (r)
			return -EFAULT;

		result += cur_size;
		buf += cur_size;
		*pos += cur_size;
		size -= cur_size;
	}

	return result;
}

static const struct file_operations radeon_ttm_gtt_fops = {
	.owner = THIS_MODULE,
	.open = radeon_ttm_gtt_open,
	.read = radeon_ttm_gtt_read,
	.llseek = default_llseek
};

#endif

static void radeon_ttm_debugfs_init(struct radeon_device *rdev)
{
#if defined(CONFIG_DEBUG_FS)
	struct drm_minor *minor = rdev->ddev->primary;
	struct dentry *root = minor->debugfs_root;

	debugfs_create_file("radeon_vram", 0444, root, rdev,
			    &radeon_ttm_vram_fops);
	debugfs_create_file("radeon_gtt", 0444, root, rdev,
			    &radeon_ttm_gtt_fops);
	debugfs_create_file("ttm_page_pool", 0444, root, rdev,
			    &radeon_ttm_page_pool_fops);
	ttm_resource_manager_create_debugfs(ttm_manager_type(&rdev->mman.bdev,
							     TTM_PL_VRAM),
					    root, "radeon_vram_mm");
	ttm_resource_manager_create_debugfs(ttm_manager_type(&rdev->mman.bdev,
							     TTM_PL_TT),
					    root, "radeon_gtt_mm");
#endif
}