/*
* 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.
*/
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");
if (r == NULL) {
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;
}
static int find_compression_threshold(struct drm_device *dev,
struct drm_mm_node *node,
int size,
int fb_cpp)
{
struct drm_i915_private *dev_priv = dev->dev_private;
int compression_threshold = 1;
int ret;
/* HACK: This code depends on what we will do in *_enable_fbc. If that
* code changes, this code needs to change as well.
*
* The enable_fbc code will attempt to use one of our 2 compression
* thresholds, therefore, in that case, we only have 1 resort.
*/
/* Try to over-allocate to reduce reallocations and fragmentation. */
ret = drm_mm_insert_node(&dev_priv->mm.stolen, node,
size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT);
if (ret == 0)
return compression_threshold;
again:
/* HW's ability to limit the CFB is 1:4 */
if (compression_threshold > 4 ||
(fb_cpp == 2 && compression_threshold == 2))
return 0;
ret = drm_mm_insert_node(&dev_priv->mm.stolen, node,
size >>= 1, 4096,
DRM_MM_SEARCH_DEFAULT);
if (ret && INTEL_INFO(dev)->gen <= 4) {
return 0;
} else if (ret) {
compression_threshold <<= 1;
goto again;
} else {
return compression_threshold;
}
}
static int i915_setup_compression(struct drm_device *dev, int size, int fb_cpp)
{
struct drm_i915_private *dev_priv = dev->dev_private;
struct drm_mm_node *uninitialized_var(compressed_llb);
int ret;
ret = find_compression_threshold(dev, &dev_priv->fbc.compressed_fb,
size, fb_cpp);
if (!ret)
goto err_llb;
else if (ret > 1) {
DRM_INFO("Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.\n");
}
dev_priv->fbc.threshold = ret;
if (HAS_PCH_SPLIT(dev))
I915_WRITE(ILK_DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start);
else if (IS_GM45(dev)) {
I915_WRITE(DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start);
} else {
compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL);
if (!compressed_llb)
goto err_fb;
ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb,
4096, 4096, DRM_MM_SEARCH_DEFAULT);
if (ret)
goto err_fb;
dev_priv->fbc.compressed_llb = compressed_llb;
I915_WRITE(FBC_CFB_BASE,
dev_priv->mm.stolen_base + dev_priv->fbc.compressed_fb.start);
I915_WRITE(FBC_LL_BASE,
dev_priv->mm.stolen_base + compressed_llb->start);
}
dev_priv->fbc.size = size / dev_priv->fbc.threshold;
DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n",
size);
return 0;
err_fb:
kfree(compressed_llb);
drm_mm_remove_node(&dev_priv->fbc.compressed_fb);
err_llb:
pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size);
return -ENOSPC;
}
int i915_gem_stolen_setup_compression(struct drm_device *dev, int size, int fb_cpp)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (!drm_mm_initialized(&dev_priv->mm.stolen))
return -ENODEV;
if (size < dev_priv->fbc.size)
return 0;
/* Release any current block */
i915_gem_stolen_cleanup_compression(dev);
return i915_setup_compression(dev, size, fb_cpp);
}
void i915_gem_stolen_cleanup_compression(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
if (dev_priv->fbc.size == 0)
return;
drm_mm_remove_node(&dev_priv->fbc.compressed_fb);
if (dev_priv->fbc.compressed_llb) {
drm_mm_remove_node(dev_priv->fbc.compressed_llb);
kfree(dev_priv->fbc.compressed_llb);
}
dev_priv->fbc.size = 0;
}
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;
i915_gem_stolen_cleanup_compression(dev);
drm_mm_takedown(&dev_priv->mm.stolen);
}
int i915_gem_init_stolen(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
u32 tmp;
int bios_reserved = 0;
#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;
DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n",
dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base);
if (INTEL_INFO(dev)->gen >= 8) {
tmp = I915_READ(GEN7_BIOS_RESERVED);
tmp >>= GEN8_BIOS_RESERVED_SHIFT;
tmp &= GEN8_BIOS_RESERVED_MASK;
bios_reserved = (1024*1024) << tmp;
} else if (IS_GEN7(dev)) {
tmp = I915_READ(GEN7_BIOS_RESERVED);
bios_reserved = tmp & GEN7_BIOS_RESERVED_256K ?
256*1024 : 1024*1024;
}
if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size))
return 0;
/* Basic memrange allocator for stolen space */
drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size -
bios_reserved);
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)
{
if (obj->stolen) {
drm_mm_remove_node(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;
obj->has_dma_mapping = true;
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 = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size,
4096, DRM_MM_SEARCH_DEFAULT);
if (ret) {
kfree(stolen);
return NULL;
}
obj = _i915_gem_object_create_stolen(dev, stolen);
if (obj)
return obj;
drm_mm_remove_node(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 */
BUG_ON(stolen_offset & 4095);
BUG_ON(size & 4095);
if (WARN_ON(size == 0))
return NULL;
stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
if (!stolen)
return NULL;
stolen->start = stolen_offset;
stolen->size = size;
ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen);
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");
drm_mm_remove_node(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:
drm_mm_remove_node(stolen);
kfree(stolen);
drm_gem_object_unreference(&obj->base);
return NULL;
}
