[mirror_ubuntu-artful-kernel.git] / drivers / gpu / drm / i915 / i915_gem_stolen.c

/*
 * Copyright © 2008-2012 Intel Corporation
 *
 * 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
 * THE AUTHORS OR COPYRIGHT HOLDERS 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.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *    Chris Wilson <chris@chris-wilson.co.uk>
 *
 */

#include <drm/drmP.h>
#include <drm/i915_drm.h>
#include "i915_drv.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(struct drm_i915_private *dev_priv,
				struct drm_mm_node *node, u64 size,
				unsigned alignment)
{
	int ret;

	if (!drm_mm_initialized(&dev_priv->mm.stolen))
		return -ENODEV;

	mutex_lock(&dev_priv->mm.stolen_lock);
	ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, size, alignment,
				 DRM_MM_SEARCH_DEFAULT);
	mutex_unlock(&dev_priv->mm.stolen_lock);

	return ret;
}

void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
				 struct drm_mm_node *node)
{
	mutex_lock(&dev_priv->mm.stolen_lock);
	drm_mm_remove_node(node);
	mutex_unlock(&dev_priv->mm.stolen_lock);
}

static unsigned long i915_stolen_to_physical(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct resource *r;
	u32 base;

	/* Almost universally we can find the Graphics Base of Stolen Memory
	 * at offset 0x5c in the igfx configuration space. On a few (desktop)
	 * machines this is also mirrored in the bridge device at different
	 * locations, or in the MCHBAR. On gen2, the layout is again slightly
	 * different with the Graphics Segment immediately following Top of
	 * Memory (or Top of Usable DRAM). Note it appears that TOUD is only
	 * reported by 865g, so we just use the top of memory as determined
	 * by the e820 probe.
	 *
	 * XXX However gen2 requires an unavailable symbol.
	 */
	base = 0;
	if (INTEL_INFO(dev)->gen >= 3) {
		/* Read Graphics Base of Stolen Memory directly */
		pci_read_config_dword(dev->pdev, 0x5c, &base);
		base &= ~((1<<20) - 1);
	} else { /* GEN2 */
#if 0
		/* Stolen is immediately above Top of Memory */
		base = max_low_pfn_mapped << PAGE_SHIFT;
#endif
	}

	if (base == 0)
		return 0;

	/* make sure we don't clobber the GTT if it's within stolen memory */
	if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
		struct {
			u32 start, end;
		} stolen[2] = {
			{ .start = base, .end = base + dev_priv->gtt.stolen_size, },
			{ .start = base, .end = base + dev_priv->gtt.stolen_size, },
		};
		u64 gtt_start, gtt_end;

		gtt_start = I915_READ(PGTBL_CTL);
		if (IS_GEN4(dev))
			gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) |
				(gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
		else
			gtt_start &= PGTBL_ADDRESS_LO_MASK;
		gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;

		if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
			stolen[0].end = gtt_start;
		if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
			stolen[1].start = gtt_end;

		/* pick the larger of the two chunks */
		if (stolen[0].end - stolen[0].start >
		    stolen[1].end - stolen[1].start) {
			base = stolen[0].start;
			dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
		} else {
			base = stolen[1].start;
			dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
		}

		if (stolen[0].start != stolen[1].start ||
		    stolen[0].end != stolen[1].end) {
			DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
				      (unsigned long long) gtt_start,
				      (unsigned long long) gtt_end - 1);
			DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
				      base, base + (u32) dev_priv->gtt.stolen_size - 1);
		}
	}


	/* 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(dev->dev, base, dev_priv->gtt.stolen_size,
				    "Graphics Stolen Memory");
	if (r == NULL) {
		/*
		 * One more attempt but this time requesting region from
		 * base + 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.
		 */
		r = devm_request_mem_region(dev->dev, base + 1,
					    dev_priv->gtt.stolen_size - 1,
					    "Graphics Stolen Memory");
		/*
		 * GEN3 firmware likes to smash pci bridges into the stolen
		 * range. Apparently this works.
		 */
		if (r == NULL && !IS_GEN3(dev)) {
			DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
				  base, base + (uint32_t)dev_priv->gtt.stolen_size);
			base = 0;
		}
	}

	return base;
}

void i915_gem_cleanup_stolen(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;

	if (!drm_mm_initialized(&dev_priv->mm.stolen))
		return;

	drm_mm_takedown(&dev_priv->mm.stolen);
}

static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
				     unsigned long *base, unsigned long *size)
{
	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);

	*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 gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
				     unsigned long *base, unsigned long *size)
{
	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);

	*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 gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
				     unsigned long *base, unsigned long *size)
{
	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);

	*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 *dev_priv,
				    unsigned long *base, unsigned long *size)
{
	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
	unsigned long stolen_top;

	stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;

	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;

	/* On these platforms, the register doesn't have a size field, so the
	 * size is the distance between the base and the top of the stolen
	 * memory. We also have the genuine case where base is zero and there's
	 * nothing reserved. */
	if (*base == 0)
		*size = 0;
	else
		*size = stolen_top - *base;
}

int i915_gem_init_stolen(struct drm_device *dev)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	unsigned long reserved_total, reserved_base, reserved_size;
	unsigned long stolen_top;

	mutex_init(&dev_priv->mm.stolen_lock);

#ifdef CONFIG_INTEL_IOMMU
	if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
		DRM_INFO("DMAR active, disabling use of stolen memory\n");
		return 0;
	}
#endif

	if (dev_priv->gtt.stolen_size == 0)
		return 0;

	dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
	if (dev_priv->mm.stolen_base == 0)
		return 0;

	stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;

	switch (INTEL_INFO(dev_priv)->gen) {
	case 2:
	case 3:
	case 4:
	case 5:
		/* Assume the gen6 maximum for the older platforms. */
		reserved_size = 1024 * 1024;
		reserved_base = stolen_top - reserved_size;
		break;
	case 6:
		gen6_get_stolen_reserved(dev_priv, &reserved_base,
					 &reserved_size);
		break;
	case 7:
		gen7_get_stolen_reserved(dev_priv, &reserved_base,
					 &reserved_size);
		break;
	default:
		if (IS_BROADWELL(dev_priv) || IS_SKYLAKE(dev_priv))
			bdw_get_stolen_reserved(dev_priv, &reserved_base,
						&reserved_size);
		else
			gen8_get_stolen_reserved(dev_priv, &reserved_base,
						 &reserved_size);
		break;
	}

	/* It is possible for the reserved base to be zero, but the register
	 * field for size doesn't have a zero option. */
	if (reserved_base == 0) {
		reserved_size = 0;
		reserved_base = stolen_top;
	}

	if (reserved_base < dev_priv->mm.stolen_base ||
	    reserved_base + reserved_size > stolen_top) {
		DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
			      reserved_base, reserved_base + reserved_size,
			      dev_priv->mm.stolen_base, stolen_top);
		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_DEBUG_KMS("Memory reserved for graphics device: %zuK, usable: %luK\n",
		      dev_priv->gtt.stolen_size >> 10,
		      (dev_priv->gtt.stolen_size - reserved_total) >> 10);

	/* Basic memrange allocator for stolen space */
	drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
		    reserved_total);

	return 0;
}

static struct sg_table *
i915_pages_create_for_stolen(struct drm_device *dev,
			     u32 offset, u32 size)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct sg_table *st;
	struct scatterlist *sg;

	DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
	BUG_ON(offset > dev_priv->gtt.stolen_size - size);

	/* 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 NULL;

	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
		kfree(st);
		return NULL;
	}

	sg = st->sgl;
	sg->offset = 0;
	sg->length = size;

	sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
	sg_dma_len(sg) = size;

	return st;
}

static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
{
	BUG();
	return -EINVAL;
}

static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
{
	/* Should only be called during free */
	sg_free_table(obj->pages);
	kfree(obj->pages);
}


static void
i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
{
	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;

	if (obj->stolen) {
		i915_gem_stolen_remove_node(dev_priv, obj->stolen);
		kfree(obj->stolen);
		obj->stolen = NULL;
	}
}
static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
	.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 drm_device *dev,
			       struct drm_mm_node *stolen)
{
	struct drm_i915_gem_object *obj;

	obj = i915_gem_object_alloc(dev);
	if (obj == NULL)
		return NULL;

	drm_gem_private_object_init(dev, &obj->base, stolen->size);
	i915_gem_object_init(obj, &i915_gem_object_stolen_ops);

	obj->pages = i915_pages_create_for_stolen(dev,
						  stolen->start, stolen->size);
	if (obj->pages == NULL)
		goto cleanup;

	i915_gem_object_pin_pages(obj);
	obj->stolen = stolen;

	obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
	obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;

	return obj;

cleanup:
	i915_gem_object_free(obj);
	return NULL;
}

struct drm_i915_gem_object *
i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct drm_i915_gem_object *obj;
	struct drm_mm_node *stolen;
	int ret;

	if (!drm_mm_initialized(&dev_priv->mm.stolen))
		return NULL;

	DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
	if (size == 0)
		return NULL;

	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
	if (!stolen)
		return NULL;

	ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
	if (ret) {
		kfree(stolen);
		return NULL;
	}

	obj = _i915_gem_object_create_stolen(dev, stolen);
	if (obj)
		return obj;

	i915_gem_stolen_remove_node(dev_priv, stolen);
	kfree(stolen);
	return NULL;
}

struct drm_i915_gem_object *
i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
					       u32 stolen_offset,
					       u32 gtt_offset,
					       u32 size)
{
	struct drm_i915_private *dev_priv = dev->dev_private;
	struct i915_address_space *ggtt = &dev_priv->gtt.base;
	struct drm_i915_gem_object *obj;
	struct drm_mm_node *stolen;
	struct i915_vma *vma;
	int ret;

	if (!drm_mm_initialized(&dev_priv->mm.stolen))
		return NULL;

	DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
			stolen_offset, gtt_offset, size);

	/* KISS and expect everything to be page-aligned */
	if (WARN_ON(size == 0) || WARN_ON(size & 4095) ||
	    WARN_ON(stolen_offset & 4095))
		return NULL;

	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
	if (!stolen)
		return NULL;

	stolen->start = stolen_offset;
	stolen->size = size;
	mutex_lock(&dev_priv->mm.stolen_lock);
	ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
	mutex_unlock(&dev_priv->mm.stolen_lock);
	if (ret) {
		DRM_DEBUG_KMS("failed to allocate stolen space\n");
		kfree(stolen);
		return NULL;
	}

	obj = _i915_gem_object_create_stolen(dev, stolen);
	if (obj == NULL) {
		DRM_DEBUG_KMS("failed to allocate stolen object\n");
		i915_gem_stolen_remove_node(dev_priv, stolen);
		kfree(stolen);
		return NULL;
	}

	/* Some objects just need physical mem from stolen space */
	if (gtt_offset == I915_GTT_OFFSET_NONE)
		return obj;

	vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
	if (IS_ERR(vma)) {
		ret = PTR_ERR(vma);
		goto err_out;
	}

	/* To simplify the initialisation sequence between KMS and GTT,
	 * we allow construction of the stolen object prior to
	 * setting up the GTT space. The actual reservation will occur
	 * later.
	 */
	vma->node.start = gtt_offset;
	vma->node.size = size;
	if (drm_mm_initialized(&ggtt->mm)) {
		ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
		if (ret) {
			DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
			goto err_vma;
		}
	}

	vma->bound |= GLOBAL_BIND;

	list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
	list_add_tail(&vma->mm_list, &ggtt->inactive_list);
	i915_gem_object_pin_pages(obj);

	return obj;

err_vma:
	i915_gem_vma_destroy(vma);
err_out:
	i915_gem_stolen_remove_node(dev_priv, stolen);
	kfree(stolen);
	drm_gem_object_unreference(&obj->base);
	return NULL;
}
Commit	Line	Data
9797fbfb CW	1	/*
	2	* Copyright © 2008-2012 Intel Corporation
	3	*
	4	* Permission is hereby granted, free of charge, to any person obtaining a
	5	* copy of this software and associated documentation files (the "Software"),
	6	* to deal in the Software without restriction, including without limitation
	7	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	8	* and/or sell copies of the Software, and to permit persons to whom the
	9	* Software is furnished to do so, subject to the following conditions:
	10	*
	11	* The above copyright notice and this permission notice (including the next
	12	* paragraph) shall be included in all copies or substantial portions of the
	13	* Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	19	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	20	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	21	* IN THE SOFTWARE.
	22	*
	23	* Authors:
	24	* Eric Anholt <eric@anholt.net>
	25	* Chris Wilson <chris@chris-wilson.co.uk>
	26	*
	27	*/
	28
760285e7 DH	29	#include <drm/drmP.h>
760285e7 DH	30	#include <drm/i915_drm.h>
9797fbfb CW	31	#include "i915_drv.h"
	32
	33	/*
	34	* The BIOS typically reserves some of the system's memory for the exclusive
	35	* use of the integrated graphics. This memory is no longer available for
	36	* use by the OS and so the user finds that his system has less memory
	37	* available than he put in. We refer to this memory as stolen.
	38	*
	39	* The BIOS will allocate its framebuffer from the stolen memory. Our
	40	* goal is try to reuse that object for our own fbcon which must always
	41	* be available for panics. Anything else we can reuse the stolen memory
	42	* for is a boon.
	43	*/
	44
d713fd49 PZ	45	int i915_gem_stolen_insert_node(struct drm_i915_private *dev_priv,
	46	struct drm_mm_node *node, u64 size,
	47	unsigned alignment)
	48	{
92e97d2f PZ	49	int ret;
92e97d2f PZ	50
d713fd49 PZ	51	if (!drm_mm_initialized(&dev_priv->mm.stolen))
	52	return -ENODEV;
	53
92e97d2f PZ	54	mutex_lock(&dev_priv->mm.stolen_lock);
	55	ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, size, alignment,
	56	DRM_MM_SEARCH_DEFAULT);
	57	mutex_unlock(&dev_priv->mm.stolen_lock);
	58
	59	return ret;
d713fd49 PZ	60	}
	61
	62	void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv,
	63	struct drm_mm_node *node)
	64	{
92e97d2f	65	mutex_lock(&dev_priv->mm.stolen_lock);
d713fd49	66	drm_mm_remove_node(node);
92e97d2f	67	mutex_unlock(&dev_priv->mm.stolen_lock);
d713fd49 PZ	68	}
d713fd49 PZ	69
e12a2d53	70	static unsigned long i915_stolen_to_physical(struct drm_device *dev)
9797fbfb CW	71	{
9797fbfb CW	72	struct drm_i915_private *dev_priv = dev->dev_private;
eaba1b8f	73	struct resource *r;
9797fbfb CW	74	u32 base;
9797fbfb CW	75
17fec8a0 CW	76	/* Almost universally we can find the Graphics Base of Stolen Memory
	77	* at offset 0x5c in the igfx configuration space. On a few (desktop)
	78	* machines this is also mirrored in the bridge device at different
	79	* locations, or in the MCHBAR. On gen2, the layout is again slightly
	80	* different with the Graphics Segment immediately following Top of
	81	* Memory (or Top of Usable DRAM). Note it appears that TOUD is only
	82	* reported by 865g, so we just use the top of memory as determined
	83	* by the e820 probe.
e12a2d53	84	*
17fec8a0	85	* XXX However gen2 requires an unavailable symbol.
9797fbfb	86	*/
e12a2d53	87	base = 0;
17fec8a0 CW	88	if (INTEL_INFO(dev)->gen >= 3) {
17fec8a0 CW	89	/* Read Graphics Base of Stolen Memory directly */
c9cddffc JB	90	pci_read_config_dword(dev->pdev, 0x5c, &base);
c9cddffc JB	91	base &= ~((1<<20) - 1);
17fec8a0	92	} else { /* GEN2 */
e12a2d53	93	#if 0
e12a2d53 CW	94	/* Stolen is immediately above Top of Memory */
e12a2d53 CW	95	base = max_low_pfn_mapped << PAGE_SHIFT;
9797fbfb	96	#endif
e12a2d53	97	}
9797fbfb	98
eaba1b8f CW	99	if (base == 0)
	100	return 0;
	101
f1e1c212 VS	102	/* make sure we don't clobber the GTT if it's within stolen memory */
	103	if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) {
	104	struct {
	105	u32 start, end;
	106	} stolen[2] = {
	107	{ .start = base, .end = base + dev_priv->gtt.stolen_size, },
	108	{ .start = base, .end = base + dev_priv->gtt.stolen_size, },
	109	};
	110	u64 gtt_start, gtt_end;
	111
	112	gtt_start = I915_READ(PGTBL_CTL);
	113	if (IS_GEN4(dev))
	114	gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) \|
	115	(gtt_start & PGTBL_ADDRESS_HI_MASK) << 28;
	116	else
	117	gtt_start &= PGTBL_ADDRESS_LO_MASK;
	118	gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4;
	119
	120	if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end)
	121	stolen[0].end = gtt_start;
	122	if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end)
	123	stolen[1].start = gtt_end;
	124
	125	/* pick the larger of the two chunks */
	126	if (stolen[0].end - stolen[0].start >
	127	stolen[1].end - stolen[1].start) {
	128	base = stolen[0].start;
	129	dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start;
	130	} else {
	131	base = stolen[1].start;
	132	dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start;
	133	}
	134
	135	if (stolen[0].start != stolen[1].start \|\|
	136	stolen[0].end != stolen[1].end) {
	137	DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n",
	138	(unsigned long long) gtt_start,
	139	(unsigned long long) gtt_end - 1);
	140	DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n",
	141	base, base + (u32) dev_priv->gtt.stolen_size - 1);
	142	}
	143	}
	144
	145
eaba1b8f CW	146	/* Verify that nothing else uses this physical address. Stolen
	147	* memory should be reserved by the BIOS and hidden from the
	148	* kernel. So if the region is already marked as busy, something
	149	* is seriously wrong.
	150	*/
	151	r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size,
	152	"Graphics Stolen Memory");
	153	if (r == NULL) {
3617dc96 AG	154	/*
	155	* One more attempt but this time requesting region from
	156	* base + 1, as we have seen that this resolves the region
	157	* conflict with the PCI Bus.
	158	* This is a BIOS w/a: Some BIOS wrap stolen in the root
	159	* PCI bus, but have an off-by-one error. Hence retry the
	160	* reservation starting from 1 instead of 0.
	161	*/
	162	r = devm_request_mem_region(dev->dev, base + 1,
	163	dev_priv->gtt.stolen_size - 1,
	164	"Graphics Stolen Memory");
0b6d24c0 DV	165	/*
	166	* GEN3 firmware likes to smash pci bridges into the stolen
	167	* range. Apparently this works.
	168	*/
	169	if (r == NULL && !IS_GEN3(dev)) {
3617dc96 AG	170	DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n",
	171	base, base + (uint32_t)dev_priv->gtt.stolen_size);
	172	base = 0;
	173	}
eaba1b8f CW	174	}
eaba1b8f CW	175
e12a2d53	176	return base;
9797fbfb CW	177	}
9797fbfb CW	178
9797fbfb CW	179	void i915_gem_cleanup_stolen(struct drm_device *dev)
9797fbfb CW	180	{
4d7bb011 DV	181	struct drm_i915_private *dev_priv = dev->dev_private;
4d7bb011 DV	182
446f8d81 DV	183	if (!drm_mm_initialized(&dev_priv->mm.stolen))
	184	return;
	185
4d7bb011	186	drm_mm_takedown(&dev_priv->mm.stolen);
9797fbfb CW	187	}
9797fbfb CW	188
3774eb50 PZ	189	static void gen6_get_stolen_reserved(struct drm_i915_private *dev_priv,
	190	unsigned long base, unsigned long size)
	191	{
	192	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
	193
	194	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
	195
	196	switch (reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK) {
	197	case GEN6_STOLEN_RESERVED_1M:
	198	size = 1024 1024;
	199	break;
	200	case GEN6_STOLEN_RESERVED_512K:
	201	size = 512 1024;
	202	break;
	203	case GEN6_STOLEN_RESERVED_256K:
	204	size = 256 1024;
	205	break;
	206	case GEN6_STOLEN_RESERVED_128K:
	207	size = 128 1024;
	208	break;
	209	default:
	210	size = 1024 1024;
	211	MISSING_CASE(reg_val & GEN6_STOLEN_RESERVED_SIZE_MASK);
	212	}
	213	}
	214
	215	static void gen7_get_stolen_reserved(struct drm_i915_private *dev_priv,
	216	unsigned long base, unsigned long size)
	217	{
	218	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
	219
	220	*base = reg_val & GEN7_STOLEN_RESERVED_ADDR_MASK;
	221
	222	switch (reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK) {
	223	case GEN7_STOLEN_RESERVED_1M:
	224	size = 1024 1024;
	225	break;
	226	case GEN7_STOLEN_RESERVED_256K:
	227	size = 256 1024;
	228	break;
	229	default:
	230	size = 1024 1024;
	231	MISSING_CASE(reg_val & GEN7_STOLEN_RESERVED_SIZE_MASK);
	232	}
	233	}
	234
	235	static void gen8_get_stolen_reserved(struct drm_i915_private *dev_priv,
	236	unsigned long base, unsigned long size)
	237	{
	238	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
	239
	240	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
	241
	242	switch (reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK) {
	243	case GEN8_STOLEN_RESERVED_1M:
	244	size = 1024 1024;
	245	break;
	246	case GEN8_STOLEN_RESERVED_2M:
	247	size = 2 1024 * 1024;
	248	break;
	249	case GEN8_STOLEN_RESERVED_4M:
	250	size = 4 1024 * 1024;
	251	break;
	252	case GEN8_STOLEN_RESERVED_8M:
253	size = 8 1024 * 1024;
254	break;
255	default:
256	size = 8 1024 * 1024;
257	MISSING_CASE(reg_val & GEN8_STOLEN_RESERVED_SIZE_MASK);
258	}
259	}
260
261	static void bdw_get_stolen_reserved(struct drm_i915_private *dev_priv,
262	unsigned long base, unsigned long size)
263	{
264	uint32_t reg_val = I915_READ(GEN6_STOLEN_RESERVED);
265	unsigned long stolen_top;
266
267	stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
268
269	*base = reg_val & GEN6_STOLEN_RESERVED_ADDR_MASK;
270
271	/* On these platforms, the register doesn't have a size field, so the
272	* size is the distance between the base and the top of the stolen
273	* memory. We also have the genuine case where base is zero and there's
274	* nothing reserved. */
275	if (*base == 0)
276	*size = 0;
277	else
278	size = stolen_top - base;
279	}
280
9797fbfb CW	281	int i915_gem_init_stolen(struct drm_device *dev)
	282	{
	283	struct drm_i915_private *dev_priv = dev->dev_private;
3774eb50 PZ	284	unsigned long reserved_total, reserved_base, reserved_size;
3774eb50 PZ	285	unsigned long stolen_top;
9797fbfb	286
92e97d2f PZ	287	mutex_init(&dev_priv->mm.stolen_lock);
92e97d2f PZ	288
0f4706d2	289	#ifdef CONFIG_INTEL_IOMMU
fcc9fe1a	290	if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) {
0f4706d2 CW	291	DRM_INFO("DMAR active, disabling use of stolen memory\n");
	292	return 0;
	293	}
	294	#endif
	295
6644a4e9 CW	296	if (dev_priv->gtt.stolen_size == 0)
	297	return 0;
	298
e12a2d53 CW	299	dev_priv->mm.stolen_base = i915_stolen_to_physical(dev);
	300	if (dev_priv->mm.stolen_base == 0)
	301	return 0;
	302
3774eb50 PZ	303	stolen_top = dev_priv->mm.stolen_base + dev_priv->gtt.stolen_size;
	304
	305	switch (INTEL_INFO(dev_priv)->gen) {
	306	case 2:
	307	case 3:
	308	case 4:
	309	case 5:
	310	/* Assume the gen6 maximum for the older platforms. */
	311	reserved_size = 1024 * 1024;
	312	reserved_base = stolen_top - reserved_size;
	313	break;
	314	case 6:
	315	gen6_get_stolen_reserved(dev_priv, &reserved_base,
	316	&reserved_size);
	317	break;
	318	case 7:
	319	gen7_get_stolen_reserved(dev_priv, &reserved_base,
	320	&reserved_size);
	321	break;
	322	default:
	323	if (IS_BROADWELL(dev_priv) \|\| IS_SKYLAKE(dev_priv))
	324	bdw_get_stolen_reserved(dev_priv, &reserved_base,
	325	&reserved_size);
	326	else
	327	gen8_get_stolen_reserved(dev_priv, &reserved_base,
	328	&reserved_size);
	329	break;
	330	}
	331
	332	/* It is possible for the reserved base to be zero, but the register
	333	* field for size doesn't have a zero option. */
	334	if (reserved_base == 0) {
	335	reserved_size = 0;
	336	reserved_base = stolen_top;
40bae736	337	}
c9cddffc	338
3774eb50 PZ	339	if (reserved_base < dev_priv->mm.stolen_base \|\|
	340	reserved_base + reserved_size > stolen_top) {
	341	DRM_DEBUG_KMS("Stolen reserved area [0x%08lx - 0x%08lx] outside stolen memory [0x%08lx - 0x%08lx]\n",
	342	reserved_base, reserved_base + reserved_size,
	343	dev_priv->mm.stolen_base, stolen_top);
897f9ed0	344	return 0;
3774eb50 PZ	345	}
	346
	347	/* It is possible for the reserved area to end before the end of stolen
	348	* memory, so just consider the start. */
	349	reserved_total = stolen_top - reserved_base;
	350
8e9d597a	351	DRM_DEBUG_KMS("Memory reserved for graphics device: %zuK, usable: %luK\n",
3774eb50 PZ	352	dev_priv->gtt.stolen_size >> 10,
3774eb50 PZ	353	(dev_priv->gtt.stolen_size - reserved_total) >> 10);
897f9ed0	354
9797fbfb	355	/* Basic memrange allocator for stolen space */
c9cddffc	356	drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
3774eb50	357	reserved_total);
9797fbfb CW	358
	359	return 0;
	360	}
0104fdbb CW	361
	362	static struct sg_table *
	363	i915_pages_create_for_stolen(struct drm_device *dev,
	364	u32 offset, u32 size)
	365	{
	366	struct drm_i915_private *dev_priv = dev->dev_private;
	367	struct sg_table *st;
	368	struct scatterlist *sg;
	369
	370	DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size);
a54c0c27	371	BUG_ON(offset > dev_priv->gtt.stolen_size - size);
0104fdbb CW	372
	373	/* We hide that we have no struct page backing our stolen object
	374	* by wrapping the contiguous physical allocation with a fake
	375	* dma mapping in a single scatterlist.
	376	*/
	377
	378	st = kmalloc(sizeof(*st), GFP_KERNEL);
	379	if (st == NULL)
	380	return NULL;
	381
	382	if (sg_alloc_table(st, 1, GFP_KERNEL)) {
	383	kfree(st);
	384	return NULL;
	385	}
	386
	387	sg = st->sgl;
ec14ba47	388	sg->offset = 0;
ed23abdd	389	sg->length = size;
0104fdbb CW	390
	391	sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset;
	392	sg_dma_len(sg) = size;
	393
	394	return st;
	395	}
	396
	397	static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj)
	398	{
	399	BUG();
	400	return -EINVAL;
	401	}
	402
	403	static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj)
	404	{
	405	/* Should only be called during free */
	406	sg_free_table(obj->pages);
	407	kfree(obj->pages);
	408	}
	409
ef0cf27c CW	410
	411	static void
	412	i915_gem_object_release_stolen(struct drm_i915_gem_object *obj)
	413	{
d713fd49 PZ	414	struct drm_i915_private *dev_priv = obj->base.dev->dev_private;
d713fd49 PZ	415
ef0cf27c	416	if (obj->stolen) {
d713fd49	417	i915_gem_stolen_remove_node(dev_priv, obj->stolen);
ef0cf27c CW	418	kfree(obj->stolen);
	419	obj->stolen = NULL;
	420	}
	421	}
0104fdbb CW	422	static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = {
	423	.get_pages = i915_gem_object_get_pages_stolen,
	424	.put_pages = i915_gem_object_put_pages_stolen,
ef0cf27c	425	.release = i915_gem_object_release_stolen,
0104fdbb CW	426	};
	427
	428	static struct drm_i915_gem_object *
	429	_i915_gem_object_create_stolen(struct drm_device *dev,
	430	struct drm_mm_node *stolen)
	431	{
	432	struct drm_i915_gem_object *obj;
	433
42dcedd4	434	obj = i915_gem_object_alloc(dev);
0104fdbb CW	435	if (obj == NULL)
	436	return NULL;
	437
89c8233f	438	drm_gem_private_object_init(dev, &obj->base, stolen->size);
0104fdbb CW	439	i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
	440
	441	obj->pages = i915_pages_create_for_stolen(dev,
	442	stolen->start, stolen->size);
	443	if (obj->pages == NULL)
	444	goto cleanup;
	445
dd53e1b0	446	i915_gem_object_pin_pages(obj);
0104fdbb CW	447	obj->stolen = stolen;
0104fdbb CW	448
d46f1c3f CW	449	obj->base.read_domains = I915_GEM_DOMAIN_CPU \| I915_GEM_DOMAIN_GTT;
d46f1c3f CW	450	obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
0104fdbb CW	451
	452	return obj;
	453
	454	cleanup:
42dcedd4	455	i915_gem_object_free(obj);
0104fdbb CW	456	return NULL;
	457	}
	458
	459	struct drm_i915_gem_object *
	460	i915_gem_object_create_stolen(struct drm_device *dev, u32 size)
	461	{
	462	struct drm_i915_private *dev_priv = dev->dev_private;
	463	struct drm_i915_gem_object *obj;
	464	struct drm_mm_node *stolen;
06e78edf	465	int ret;
0104fdbb	466
446f8d81	467	if (!drm_mm_initialized(&dev_priv->mm.stolen))
0104fdbb CW	468	return NULL;
	469
	470	DRM_DEBUG_KMS("creating stolen object: size=%x\n", size);
	471	if (size == 0)
	472	return NULL;
	473
06e78edf DH	474	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
06e78edf DH	475	if (!stolen)
0104fdbb CW	476	return NULL;
0104fdbb CW	477
d713fd49	478	ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
06e78edf DH	479	if (ret) {
	480	kfree(stolen);
	481	return NULL;
	482	}
	483
0104fdbb CW	484	obj = _i915_gem_object_create_stolen(dev, stolen);
	485	if (obj)
	486	return obj;
	487
d713fd49	488	i915_gem_stolen_remove_node(dev_priv, stolen);
06e78edf	489	kfree(stolen);
0104fdbb CW	490	return NULL;
	491	}
	492
866d12b4 CW	493	struct drm_i915_gem_object *
	494	i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev,
	495	u32 stolen_offset,
	496	u32 gtt_offset,
	497	u32 size)
	498	{
	499	struct drm_i915_private *dev_priv = dev->dev_private;
40d74980	500	struct i915_address_space *ggtt = &dev_priv->gtt.base;
866d12b4 CW	501	struct drm_i915_gem_object *obj;
866d12b4 CW	502	struct drm_mm_node *stolen;
2f633156	503	struct i915_vma *vma;
b3a070cc	504	int ret;
866d12b4	505
446f8d81	506	if (!drm_mm_initialized(&dev_priv->mm.stolen))
866d12b4 CW	507	return NULL;
	508
	509	DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n",
	510	stolen_offset, gtt_offset, size);
	511
	512	/* KISS and expect everything to be page-aligned */
f37b5c2b DV	513	if (WARN_ON(size == 0) \|\| WARN_ON(size & 4095) \|\|
f37b5c2b DV	514	WARN_ON(stolen_offset & 4095))
866d12b4 CW	515	return NULL;
866d12b4 CW	516
b3a070cc BW	517	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
	518	if (!stolen)
	519	return NULL;
	520
338710e7 BW	521	stolen->start = stolen_offset;
338710e7 BW	522	stolen->size = size;
92e97d2f	523	mutex_lock(&dev_priv->mm.stolen_lock);
338710e7	524	ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
92e97d2f	525	mutex_unlock(&dev_priv->mm.stolen_lock);
b3a070cc	526	if (ret) {
866d12b4	527	DRM_DEBUG_KMS("failed to allocate stolen space\n");
b3a070cc	528	kfree(stolen);
866d12b4 CW	529	return NULL;
	530	}
	531
	532	obj = _i915_gem_object_create_stolen(dev, stolen);
	533	if (obj == NULL) {
	534	DRM_DEBUG_KMS("failed to allocate stolen object\n");
d713fd49	535	i915_gem_stolen_remove_node(dev_priv, stolen);
06e78edf	536	kfree(stolen);
866d12b4 CW	537	return NULL;
	538	}
	539
3727d55e	540	/* Some objects just need physical mem from stolen space */
190d6cd5	541	if (gtt_offset == I915_GTT_OFFSET_NONE)
3727d55e JB	542	return obj;
3727d55e JB	543
e656a6cb	544	vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt);
db473b36 DC	545	if (IS_ERR(vma)) {
db473b36 DC	546	ret = PTR_ERR(vma);
2f633156 BW	547	goto err_out;
	548	}
	549
866d12b4 CW	550	/* To simplify the initialisation sequence between KMS and GTT,
	551	* we allow construction of the stolen object prior to
	552	* setting up the GTT space. The actual reservation will occur
	553	* later.
	554	*/
2f633156 BW	555	vma->node.start = gtt_offset;
2f633156 BW	556	vma->node.size = size;
40d74980 BW	557	if (drm_mm_initialized(&ggtt->mm)) {
40d74980 BW	558	ret = drm_mm_reserve_node(&ggtt->mm, &vma->node);
b3a070cc	559	if (ret) {
866d12b4	560	DRM_DEBUG_KMS("failed to allocate stolen GTT space\n");
4a025e26	561	goto err_vma;
866d12b4	562	}
edd41a87	563	}
866d12b4	564
aff43766	565	vma->bound \|= GLOBAL_BIND;
866d12b4	566
35c20a60	567	list_add_tail(&obj->global_list, &dev_priv->mm.bound_list);
ca191b13	568	list_add_tail(&vma->mm_list, &ggtt->inactive_list);
d8ccba86	569	i915_gem_object_pin_pages(obj);
866d12b4 CW	570
866d12b4 CW	571	return obj;
b3a070cc	572
4a025e26 DV	573	err_vma:
4a025e26 DV	574	i915_gem_vma_destroy(vma);
f7f18184	575	err_out:
d713fd49	576	i915_gem_stolen_remove_node(dev_priv, stolen);
32c913e4	577	kfree(stolen);
b3a070cc BW	578	drm_gem_object_unreference(&obj->base);
b3a070cc BW	579	return NULL;
866d12b4	580	}