Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 739 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
new file mode 100644
index 000000000..84b2707d8
--- /dev/null
+++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
@@ -0,0 +1,739 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2008-2012 Intel Corporation
+ */
+
+#include <linux/errno.h>
+#include <linux/mutex.h>
+
+#include <drm/drm_mm.h>
+#include <drm/i915_drm.h>
+
+#include "gem/i915_gem_region.h"
+#include "i915_drv.h"
+#include "i915_gem_stolen.h"
+#include "i915_vgpu.h"
+
+/*
+ * The BIOS typically reserves some of the system's memory for the exclusive
+ * use of the integrated graphics. This memory is no longer available for
+ * use by the OS and so the user finds that his system has less memory
+ * available than he put in. We refer to this memory as stolen.
+ *
+ * The BIOS will allocate its framebuffer from the stolen memory. Our
+ * goal is try to reuse that object for our own fbcon which must always
+ * be available for panics. Anything else we can reuse the stolen memory
+ * for is a boon.
+ */
+
+int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *i915,
+					 struct drm_mm_node *node, u64 size,
+					 unsigned alignment, u64 start, u64 end)
+{
+	int ret;
+
+	if (!drm_mm_initialized(&i915->mm.stolen))
+		return -ENODEV;
+
+	/* WaSkipStolenMemoryFirstPage:bdw+ */
+	if (INTEL_GEN(i915) >= 8 && start < 4096)
+		start = 4096;
+
+	mutex_lock(&i915->mm.stolen_lock);
+	ret = drm_mm_insert_node_in_range(&i915->mm.stolen, node,
+					  size, alignment, 0,
+					  start, end, DRM_MM_INSERT_BEST);
+	mutex_unlock(&i915->mm.stolen_lock);
+
+	return ret;
+}
+
+int i915_gem_stolen_insert_node(struct drm_i915_private *i915,
+				struct drm_mm_node *node, u64 size,
+				unsigned alignment)
+{
+	return i915_gem_stolen_insert_node_in_range(i915, node,
+						    size, alignment,
+						    I915_GEM_STOLEN_BIAS,
+						    U64_MAX);
+}
+
+void i915_gem_stolen_remove_node(struct drm_i915_private *i915,
+				 struct drm_mm_node *node)
+{
+	mutex_lock(&i915->mm.stolen_lock);
+	drm_mm_remove_node(node);
+	mutex_unlock(&i915->mm.stolen_lock);
+}
+
+static int i915_adjust_stolen(struct drm_i915_private *i915,
+			      struct resource *dsm)
+{
+	struct i915_ggtt *ggtt = &i915->ggtt;
+	struct intel_uncore *uncore = ggtt->vm.gt->uncore;
+	struct resource *r;
+
+	if (dsm->start == 0 || dsm->end <= dsm->start)
+		return -EINVAL;
+
+	/*
+	 * TODO: We have yet too encounter the case where the GTT wasn't at the
+	 * end of stolen. With that assumption we could simplify this.
+	 */
+
+	/* Make sure we don't clobber the GTT if it's within stolen memory */
+	if (INTEL_GEN(i915) <= 4 &&
+	    !IS_G33(i915) && !IS_PINEVIEW(i915) && !IS_G4X(i915)) {
+		struct resource stolen[2] = {*dsm, *dsm};
+		struct resource ggtt_res;
+		resource_size_t ggtt_start;
+
+		ggtt_start = intel_uncore_read(uncore, PGTBL_CTL);
+		if (IS_GEN(i915, 4))
+			ggtt_start = (ggtt_start & PGTBL_ADDRESS_LO_MASK) |
+				     (ggtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
+		else
+			ggtt_start &= PGTBL_ADDRESS_LO_MASK;
+
+		ggtt_res =
+			(struct resource) DEFINE_RES_MEM(ggtt_start,
+							 ggtt_total_entries(ggtt) * 4);
+
+		if (ggtt_res.start >= stolen[0].start && ggtt_res.start < stolen[0].end)
+			stolen[0].end = ggtt_res.start;
+		if (ggtt_res.end > stolen[1].start && ggtt_res.end <= stolen[1].end)
+			stolen[1].start = ggtt_res.end;
+
+		/* Pick the larger of the two chunks */
+		if (resource_size(&stolen[0]) > resource_size(&stolen[1]))
+			*dsm = stolen[0];
+		else
+			*dsm = stolen[1];
+
+		if (stolen[0].start != stolen[1].start ||
+		    stolen[0].end != stolen[1].end) {
+			drm_dbg(&i915->drm,
+				"GTT within stolen memory at %pR\n",
+				&ggtt_res);
+			drm_dbg(&i915->drm, "Stolen memory adjusted to %pR\n",
+				dsm);
+		}
+	}
+
+	/*
+	 * Verify that nothing else uses this physical address. Stolen
+	 * memory should be reserved by the BIOS and hidden from the
+	 * kernel. So if the region is already marked as busy, something
+	 * is seriously wrong.
+	 */
+	r = devm_request_mem_region(i915->drm.dev, dsm->start,
+				    resource_size(dsm),
+				    "Graphics Stolen Memory");
+	if (r == NULL) {
+		/*
+		 * One more attempt but this time requesting region from
+		 * start + 1, as we have seen that this resolves the region
+		 * conflict with the PCI Bus.
+		 * This is a BIOS w/a: Some BIOS wrap stolen in the root
+		 * PCI bus, but have an off-by-one error. Hence retry the
+		 * reservation starting from 1 instead of 0.
+		 * There's also BIOS with off-by-one on the other end.
+		 */
+		r = devm_request_mem_region(i915->drm.dev, dsm->start + 1,
+					    resource_size(dsm) - 2,
+					    "Graphics Stolen Memory");
+		/*
+		 * GEN3 firmware likes to smash pci bridges into the stolen
+		 * range. Apparently this works.
+		 */
+		if (!r && !IS_GEN(i915, 3)) {
+			drm_err(&i915->drm,
+				"conflict detected with stolen region: %pR\n",
+				dsm);
+
+			return -EBUSY;
+		}
+	}
+
+	return 0;
+}
+
+static void i915_gem_cleanup_stolen(struct drm_i915_private *i915)
+{
+	if (!drm_mm_initialized(&i915->mm.stolen))
+		return;
+
+	drm_mm_takedown(&i915->mm.stolen);
+}
+
+static void g4x_get_stolen_reserved(struct drm_i915_private *i915,
+				    struct intel_uncore *uncore,
+				    resource_size_t *base,
+				    resource_size_t *size)
+{
+	u32 reg_val = intel_uncore_read(uncore,
+					IS_GM45(i915) ?
+					CTG_STOLEN_RESERVED :
+					ELK_STOLEN_RESERVED);
+	resource_size_t stolen_top = i915->dsm.end + 1;
+
+	drm_dbg(&i915->drm, "%s_STOLEN_RESERVED = %08x\n",
+		IS_GM45(i915) ? "CTG" : "ELK", reg_val);
+
+	if ((reg_val & G4X_STOLEN_RESERVED_ENABLE) == 0)
+		return;
+
+	/*
+	 * Whether ILK really reuses the ELK register for this is unclear.
+	 * Let's see if we catch anyone with this supposedly enabled on ILK.
+	 */
+	drm_WARN(&i915->drm, IS_GEN(i915, 5),
+		 "ILK stolen reserved found? 0x%08x\n",
+		 reg_val);
+
+	if (!(reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK))
+		return;
+
+	*base = (reg_val & G4X_STOLEN_RESERVED_ADDR2_MASK) << 16;
+	drm_WARN_ON(&i915->drm,
+		    (reg_val & G4X_STOLEN_RESERVED_ADDR1_MASK) < *base);
+
+	*size = stolen_top - *base;
+}
+
+static void gen6_get_stolen_reserved(struct drm_i915_private *i915,
+				     struct intel_uncore *uncore,
+				     resource_size_t *base,
+				     resource_size_t *size)
+{
+	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
+
+	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
+
+	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
+		return;
+
+	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
+
+	switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
+	case GEN6_STOLEN_RESERVED_1M:
+		*size = 1024 * 1024;
+		break;
+	case GEN6_STOLEN_RESERVED_512K:
+		*size = 512 * 1024;
+		break;
+	case GEN6_STOLEN_RESERVED_256K:
+		*size = 256 * 1024;
+		break;
+	case GEN6_STOLEN_RESERVED_128K:
+		*size = 128 * 1024;
+		break;
+	default:
+		*size = 1024 * 1024;
+		MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
+	}
+}
+
+static void vlv_get_stolen_reserved(struct drm_i915_private *i915,
+				    struct intel_uncore *uncore,
+				    resource_size_t *base,
+				    resource_size_t *size)
+{
+	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
+	resource_size_t stolen_top = i915->dsm.end + 1;
+
+	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
+
+	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
+		return;
+
+	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
+	default:
+		MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
+		fallthrough;
+	case GEN7_STOLEN_RESERVED_1M:
+		*size = 1024 * 1024;
+		break;
+	}
+
+	/*
+	 * On vlv, the ADDR_MASK portion is left as 0 and HW deduces the
+	 * reserved location as (top - size).
+	 */
+	*base = stolen_top - *size;
+}
+
+static void gen7_get_stolen_reserved(struct drm_i915_private *i915,
+				     struct intel_uncore *uncore,
+				     resource_size_t *base,
+				     resource_size_t *size)
+{
+	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
+
+	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
+
+	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
+		return;
+
+	*base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
+
+	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
+	case GEN7_STOLEN_RESERVED_1M:
+		*size = 1024 * 1024;
+		break;
+	case GEN7_STOLEN_RESERVED_256K:
+		*size = 256 * 1024;
+		break;
+	default:
+		*size = 1024 * 1024;
+		MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
+	}
+}
+
+static void chv_get_stolen_reserved(struct drm_i915_private *i915,
+				    struct intel_uncore *uncore,
+				    resource_size_t *base,
+				    resource_size_t *size)
+{
+	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
+
+	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
+
+	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
+		return;
+
+	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
+
+	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
+	case GEN8_STOLEN_RESERVED_1M:
+		*size = 1024 * 1024;
+		break;
+	case GEN8_STOLEN_RESERVED_2M:
+		*size = 2 * 1024 * 1024;
+		break;
+	case GEN8_STOLEN_RESERVED_4M:
+		*size = 4 * 1024 * 1024;
+		break;
+	case GEN8_STOLEN_RESERVED_8M:
+		*size = 8 * 1024 * 1024;
+		break;
+	default:
+		*size = 8 * 1024 * 1024;
+		MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
+	}
+}
+
+static void bdw_get_stolen_reserved(struct drm_i915_private *i915,
+				    struct intel_uncore *uncore,
+				    resource_size_t *base,
+				    resource_size_t *size)
+{
+	u32 reg_val = intel_uncore_read(uncore, GEN6_STOLEN_RESERVED);
+	resource_size_t stolen_top = i915->dsm.end + 1;
+
+	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = %08x\n", reg_val);
+
+	if (!(reg_val & GEN6_STOLEN_RESERVED_ENABLE))
+		return;
+
+	if (!(reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK))
+		return;
+
+	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
+	*size = stolen_top - *base;
+}
+
+static void icl_get_stolen_reserved(struct drm_i915_private *i915,
+				    struct intel_uncore *uncore,
+				    resource_size_t *base,
+				    resource_size_t *size)
+{
+	u64 reg_val = intel_uncore_read64(uncore, GEN6_STOLEN_RESERVED);
+
+	drm_dbg(&i915->drm, "GEN6_STOLEN_RESERVED = 0x%016llx\n", reg_val);
+
+	*base = reg_val & GEN11_STOLEN_RESERVED_ADDR_MASK;
+
+	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
+	case GEN8_STOLEN_RESERVED_1M:
+		*size = 1024 * 1024;
+		break;
+	case GEN8_STOLEN_RESERVED_2M:
+		*size = 2 * 1024 * 1024;
+		break;
+	case GEN8_STOLEN_RESERVED_4M:
+		*size = 4 * 1024 * 1024;
+		break;
+	case GEN8_STOLEN_RESERVED_8M:
+		*size = 8 * 1024 * 1024;
+		break;
+	default:
+		*size = 8 * 1024 * 1024;
+		MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
+	}
+}
+
+static int i915_gem_init_stolen(struct drm_i915_private *i915)
+{
+	struct intel_uncore *uncore = &i915->uncore;
+	resource_size_t reserved_base, stolen_top;
+	resource_size_t reserved_total, reserved_size;
+
+	mutex_init(&i915->mm.stolen_lock);
+
+	if (intel_vgpu_active(i915)) {
+		drm_notice(&i915->drm,
+			   "%s, disabling use of stolen memory\n",
+			   "iGVT-g active");
+		return 0;
+	}
+
+	if (intel_vtd_active() && INTEL_GEN(i915) < 8) {
+		drm_notice(&i915->drm,
+			   "%s, disabling use of stolen memory\n",
+			   "DMAR active");
+		return 0;
+	}
+
+	if (resource_size(&intel_graphics_stolen_res) == 0)
+		return 0;
+
+	i915->dsm = intel_graphics_stolen_res;
+
+	if (i915_adjust_stolen(i915, &i915->dsm))
+		return 0;
+
+	GEM_BUG_ON(i915->dsm.start == 0);
+	GEM_BUG_ON(i915->dsm.end <= i915->dsm.start);
+
+	stolen_top = i915->dsm.end + 1;
+	reserved_base = stolen_top;
+	reserved_size = 0;
+
+	switch (INTEL_GEN(i915)) {
+	case 2:
+	case 3:
+		break;
+	case 4:
+		if (!IS_G4X(i915))
+			break;
+		fallthrough;
+	case 5:
+		g4x_get_stolen_reserved(i915, uncore,
+					&reserved_base, &reserved_size);
+		break;
+	case 6:
+		gen6_get_stolen_reserved(i915, uncore,
+					 &reserved_base, &reserved_size);
+		break;
+	case 7:
+		if (IS_VALLEYVIEW(i915))
+			vlv_get_stolen_reserved(i915, uncore,
+						&reserved_base, &reserved_size);
+		else
+			gen7_get_stolen_reserved(i915, uncore,
+						 &reserved_base, &reserved_size);
+		break;
+	case 8:
+	case 9:
+	case 10:
+		if (IS_LP(i915))
+			chv_get_stolen_reserved(i915, uncore,
+						&reserved_base, &reserved_size);
+		else
+			bdw_get_stolen_reserved(i915, uncore,
+						&reserved_base, &reserved_size);
+		break;
+	default:
+		MISSING_CASE(INTEL_GEN(i915));
+		fallthrough;
+	case 11:
+	case 12:
+		icl_get_stolen_reserved(i915, uncore,
+					&reserved_base,
+					&reserved_size);
+		break;
+	}
+
+	/*
+	 * Our expectation is that the reserved space is at the top of the
+	 * stolen region and *never* at the bottom. If we see !reserved_base,
+	 * it likely means we failed to read the registers correctly.
+	 */
+	if (!reserved_base) {
+		drm_err(&i915->drm,
+			"inconsistent reservation %pa + %pa; ignoring\n",
+			&reserved_base, &reserved_size);
+		reserved_base = stolen_top;
+		reserved_size = 0;
+	}
+
+	i915->dsm_reserved =
+		(struct resource)DEFINE_RES_MEM(reserved_base, reserved_size);
+
+	if (!resource_contains(&i915->dsm, &i915->dsm_reserved)) {
+		drm_err(&i915->drm,
+			"Stolen reserved area %pR outside stolen memory %pR\n",
+			&i915->dsm_reserved, &i915->dsm);
+		return 0;
+	}
+
+	/* It is possible for the reserved area to end before the end of stolen
+	 * memory, so just consider the start. */
+	reserved_total = stolen_top - reserved_base;
+
+	drm_dbg(&i915->drm,
+		"Memory reserved for graphics device: %lluK, usable: %lluK\n",
+		(u64)resource_size(&i915->dsm) >> 10,
+		((u64)resource_size(&i915->dsm) - reserved_total) >> 10);
+
+	i915->stolen_usable_size =
+		resource_size(&i915->dsm) - reserved_total;
+
+	/* Basic memrange allocator for stolen space. */
+	drm_mm_init(&i915->mm.stolen, 0, i915->stolen_usable_size);
+
+	return 0;
+}
+
+static struct sg_table *
+i915_pages_create_for_stolen(struct drm_device *dev,
+			     resource_size_t offset, resource_size_t size)
+{
+	struct drm_i915_private *i915 = to_i915(dev);
+	struct sg_table *st;
+	struct scatterlist *sg;
+
+	GEM_BUG_ON(range_overflows(offset, size, resource_size(&i915->dsm)));
+
+	/* We hide that we have no struct page backing our stolen object
+	 * by wrapping the contiguous physical allocation with a fake
+	 * dma mapping in a single scatterlist.
+	 */
+
+	st = kmalloc(sizeof(*st), GFP_KERNEL);
+	if (st == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
+		kfree(st);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	sg = st->sgl;
+	sg->offset = 0;
+	sg->length = size;
+
+	sg_dma_address(sg) = (dma_addr_t)i915->dsm.start + offset;
+	sg_dma_len(sg) = size;
+
+	return st;
+}
+
+static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
+{
+	struct sg_table *pages =
+		i915_pages_create_for_stolen(obj->base.dev,
+					     obj->stolen->start,
+					     obj->stolen->size);
+	if (IS_ERR(pages))
+		return PTR_ERR(pages);
+
+	__i915_gem_object_set_pages(obj, pages, obj->stolen->size);
+
+	return 0;
+}
+
+static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj,
+					     struct sg_table *pages)
+{
+	/* Should only be called from i915_gem_object_release_stolen() */
+	sg_free_table(pages);
+	kfree(pages);
+}
+
+static void
+i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
+{
+	struct drm_i915_private *i915 = to_i915(obj->base.dev);
+	struct drm_mm_node *stolen = fetch_and_zero(&obj->stolen);
+
+	GEM_BUG_ON(!stolen);
+
+	i915_gem_object_release_memory_region(obj);
+
+	i915_gem_stolen_remove_node(i915, stolen);
+	kfree(stolen);
+}
+
+static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
+	.name = "i915_gem_object_stolen",
+	.get_pages = i915_gem_object_get_pages_stolen,
+	.put_pages = i915_gem_object_put_pages_stolen,
+	.release = i915_gem_object_release_stolen,
+};
+
+static struct drm_i915_gem_object *
+__i915_gem_object_create_stolen(struct intel_memory_region *mem,
+				struct drm_mm_node *stolen)
+{
+	static struct lock_class_key lock_class;
+	struct drm_i915_gem_object *obj;
+	unsigned int cache_level;
+	int err = -ENOMEM;
+
+	obj = i915_gem_object_alloc();
+	if (!obj)
+		goto err;
+
+	drm_gem_private_object_init(&mem->i915->drm, &obj->base, stolen->size);
+	i915_gem_object_init(obj, &i915_gem_object_stolen_ops, &lock_class);
+
+	obj->stolen = stolen;
+	obj->read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
+	cache_level = HAS_LLC(mem->i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
+	i915_gem_object_set_cache_coherency(obj, cache_level);
+
+	err = i915_gem_object_pin_pages(obj);
+	if (err)
+		goto cleanup;
+
+	i915_gem_object_init_memory_region(obj, mem, 0);
+
+	return obj;
+
+cleanup:
+	i915_gem_object_free(obj);
+err:
+	return ERR_PTR(err);
+}
+
+static struct drm_i915_gem_object *
+_i915_gem_object_create_stolen(struct intel_memory_region *mem,
+			       resource_size_t size,
+			       unsigned int flags)
+{
+	struct drm_i915_private *i915 = mem->i915;
+	struct drm_i915_gem_object *obj;
+	struct drm_mm_node *stolen;
+	int ret;
+
+	if (!drm_mm_initialized(&i915->mm.stolen))
+		return ERR_PTR(-ENODEV);
+
+	if (size == 0)
+		return ERR_PTR(-EINVAL);
+
+	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
+	if (!stolen)
+		return ERR_PTR(-ENOMEM);
+
+	ret = i915_gem_stolen_insert_node(i915, stolen, size, 4096);
+	if (ret) {
+		obj = ERR_PTR(ret);
+		goto err_free;
+	}
+
+	obj = __i915_gem_object_create_stolen(mem, stolen);
+	if (IS_ERR(obj))
+		goto err_remove;
+
+	return obj;
+
+err_remove:
+	i915_gem_stolen_remove_node(i915, stolen);
+err_free:
+	kfree(stolen);
+	return obj;
+}
+
+struct drm_i915_gem_object *
+i915_gem_object_create_stolen(struct drm_i915_private *i915,
+			      resource_size_t size)
+{
+	return i915_gem_object_create_region(i915->mm.regions[INTEL_REGION_STOLEN],
+					     size, I915_BO_ALLOC_CONTIGUOUS);
+}
+
+static int init_stolen(struct intel_memory_region *mem)
+{
+	intel_memory_region_set_name(mem, "stolen");
+
+	/*
+	 * Initialise stolen early so that we may reserve preallocated
+	 * objects for the BIOS to KMS transition.
+	 */
+	return i915_gem_init_stolen(mem->i915);
+}
+
+static void release_stolen(struct intel_memory_region *mem)
+{
+	i915_gem_cleanup_stolen(mem->i915);
+}
+
+static const struct intel_memory_region_ops i915_region_stolen_ops = {
+	.init = init_stolen,
+	.release = release_stolen,
+	.create_object = _i915_gem_object_create_stolen,
+};
+
+struct intel_memory_region *i915_gem_stolen_setup(struct drm_i915_private *i915)
+{
+	return intel_memory_region_create(i915,
+					  intel_graphics_stolen_res.start,
+					  resource_size(&intel_graphics_stolen_res),
+					  PAGE_SIZE, 0,
+					  &i915_region_stolen_ops);
+}
+
+struct drm_i915_gem_object *
+i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *i915,
+					       resource_size_t stolen_offset,
+					       resource_size_t size)
+{
+	struct intel_memory_region *mem = i915->mm.regions[INTEL_REGION_STOLEN];
+	struct drm_i915_gem_object *obj;
+	struct drm_mm_node *stolen;
+	int ret;
+
+	if (!drm_mm_initialized(&i915->mm.stolen))
+		return ERR_PTR(-ENODEV);
+
+	drm_dbg(&i915->drm,
+		"creating preallocated stolen object: stolen_offset=%pa, size=%pa\n",
+		&stolen_offset, &size);
+
+	/* KISS and expect everything to be page-aligned */
+	if (GEM_WARN_ON(size == 0) ||
+	    GEM_WARN_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE)) ||
+	    GEM_WARN_ON(!IS_ALIGNED(stolen_offset, I915_GTT_MIN_ALIGNMENT)))
+		return ERR_PTR(-EINVAL);
+
+	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
+	if (!stolen)
+		return ERR_PTR(-ENOMEM);
+
+	stolen->start = stolen_offset;
+	stolen->size = size;
+	mutex_lock(&i915->mm.stolen_lock);
+	ret = drm_mm_reserve_node(&i915->mm.stolen, stolen);
+	mutex_unlock(&i915->mm.stolen_lock);
+	if (ret) {
+		obj = ERR_PTR(ret);
+		goto err_free;
+	}
+
+	obj = __i915_gem_object_create_stolen(mem, stolen);
+	if (IS_ERR(obj))
+		goto err_stolen;
+
+	i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
+	return obj;
+
+err_stolen:
+	i915_gem_stolen_remove_node(i915, stolen);
+err_free:
+	kfree(stolen);
+	return obj;
+}