static int assign_hw_id(struct drm_i915_private *dev_priv, unsigned *out)
{
int ret;
ret = ida_simple_get(&dev_priv->context_hw_ida,
0, MAX_CONTEXT_HW_ID, GFP_KERNEL);
if (ret < 0) {
/* Contexts are only released when no longer active.
* Flush any pending retires to hopefully release some
* stale contexts and try again.
*/
i915_gem_retire_requests(dev_priv);
ret = ida_simple_get(&dev_priv->context_hw_ida,
0, MAX_CONTEXT_HW_ID, GFP_KERNEL);
if (ret < 0)
return ret;
}
*out = ret;
return 0;
}
/**
* i915_gem_shrink - Shrink buffer object caches
* @dev_priv: i915 device
* @target: amount of memory to make available, in pages
* @nr_scanned: optional output for number of pages scanned (incremental)
* @flags: control flags for selecting cache types
*
* This function is the main interface to the shrinker. It will try to release
* up to @target pages of main memory backing storage from buffer objects.
* Selection of the specific caches can be done with @flags. This is e.g. useful
* when purgeable objects should be removed from caches preferentially.
*
* Note that it's not guaranteed that released amount is actually available as
* free system memory - the pages might still be in-used to due to other reasons
* (like cpu mmaps) or the mm core has reused them before we could grab them.
* Therefore code that needs to explicitly shrink buffer objects caches (e.g. to
* avoid deadlocks in memory reclaim) must fall back to i915_gem_shrink_all().
*
* Also note that any kind of pinning (both per-vma address space pins and
* backing storage pins at the buffer object level) result in the shrinker code
* having to skip the object.
*
* Returns:
* The number of pages of backing storage actually released.
*/
unsigned long
i915_gem_shrink(struct drm_i915_private *dev_priv,
unsigned long target,
unsigned long *nr_scanned,
unsigned flags)
{
const struct {
struct list_head *list;
unsigned int bit;
} phases[] = {
{ &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
{ &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
{ NULL, 0 },
}, *phase;
unsigned long count = 0;
unsigned long scanned = 0;
bool unlock;
if (!shrinker_lock(dev_priv, &unlock))
return 0;
/*
* When shrinking the active list, also consider active contexts.
* Active contexts are pinned until they are retired, and so can
* not be simply unbound to retire and unpin their pages. To shrink
* the contexts, we must wait until the gpu is idle.
*
* We don't care about errors here; if we cannot wait upon the GPU,
* we will free as much as we can and hope to get a second chance.
*/
if (flags & I915_SHRINK_ACTIVE)
i915_gem_wait_for_idle(dev_priv, I915_WAIT_LOCKED);
trace_i915_gem_shrink(dev_priv, target, flags);
i915_gem_retire_requests(dev_priv);
/*
* Unbinding of objects will require HW access; Let us not wake the
* device just to recover a little memory. If absolutely necessary,
* we will force the wake during oom-notifier.
*/
if ((flags & I915_SHRINK_BOUND) &&
!intel_runtime_pm_get_if_in_use(dev_priv))
flags &= ~I915_SHRINK_BOUND;
/*
* As we may completely rewrite the (un)bound list whilst unbinding
* (due to retiring requests) we have to strictly process only
* one element of the list at the time, and recheck the list
* on every iteration.
*
* In particular, we must hold a reference whilst removing the
* object as we may end up waiting for and/or retiring the objects.
* This might release the final reference (held by the active list)
* and result in the object being freed from under us. This is
* similar to the precautions the eviction code must take whilst
* removing objects.
*
* Also note that although these lists do not hold a reference to
* the object we can safely grab one here: The final object
* unreferencing and the bound_list are both protected by the
* dev->struct_mutex and so we won't ever be able to observe an
* object on the bound_list with a reference count equals 0.
*/
for (phase = phases; phase->list; phase++) {
struct list_head still_in_list;
struct drm_i915_gem_object *obj;
if ((flags & phase->bit) == 0)
continue;
INIT_LIST_HEAD(&still_in_list);
/*
* We serialize our access to unreferenced objects through
* the use of the struct_mutex. While the objects are not
* yet freed (due to RCU then a workqueue) we still want
* to be able to shrink their pages, so they remain on
* the unbound/bound list until actually freed.
*/
spin_lock(&dev_priv->mm.obj_lock);
while (count < target &&
(obj = list_first_entry_or_null(phase->list,
typeof(*obj),
mm.link))) {
list_move_tail(&obj->mm.link, &still_in_list);
if (flags & I915_SHRINK_PURGEABLE &&
obj->mm.madv != I915_MADV_DONTNEED)
continue;
if (flags & I915_SHRINK_VMAPS &&
!is_vmalloc_addr(obj->mm.mapping))
continue;
if (!(flags & I915_SHRINK_ACTIVE) &&
(i915_gem_object_is_active(obj) ||
i915_gem_object_is_framebuffer(obj)))
continue;
if (!can_release_pages(obj))
continue;
spin_unlock(&dev_priv->mm.obj_lock);
if (unsafe_drop_pages(obj)) {
/* May arrive from get_pages on another bo */
mutex_lock_nested(&obj->mm.lock,
I915_MM_SHRINKER);
if (!i915_gem_object_has_pages(obj)) {
__i915_gem_object_invalidate(obj);
count += obj->base.size >> PAGE_SHIFT;
}
mutex_unlock(&obj->mm.lock);
}
scanned += obj->base.size >> PAGE_SHIFT;
spin_lock(&dev_priv->mm.obj_lock);
}
list_splice_tail(&still_in_list, phase->list);
spin_unlock(&dev_priv->mm.obj_lock);
}
/**
* i965_reset - reset chip after a hang
* @dev: drm device to reset
* @flags: reset domains
*
* Reset the chip. Useful if a hang is detected. Returns zero on successful
* reset or otherwise an error code.
*
* Procedure is fairly simple:
* - reset the chip using the reset reg
* - re-init context state
* - re-init hardware status page
* - re-init ring buffer
* - re-init interrupt state
* - re-init display
*/
int i965_reset(struct drm_device *dev, u8 flags)
{
drm_i915_private_t *dev_priv = dev->dev_private;
unsigned long timeout;
u8 gdrst;
/*
* We really should only reset the display subsystem if we actually
* need to
*/
bool need_display = true;
mutex_lock(&dev->struct_mutex);
/*
* Clear request list
*/
i915_gem_retire_requests(dev);
if (need_display)
i915_save_display(dev);
if (IS_I965G(dev) || IS_G4X(dev)) {
/*
* Set the domains we want to reset, then the reset bit (bit 0).
* Clear the reset bit after a while and wait for hardware status
* bit (bit 1) to be set
*/
pci_read_config_byte(dev->pdev, GDRST, &gdrst);
pci_write_config_byte(dev->pdev, GDRST, gdrst | flags | ((flags == GDRST_FULL) ? 0x1 : 0x0));
udelay(50);
pci_write_config_byte(dev->pdev, GDRST, gdrst & 0xfe);
/* ...we don't want to loop forever though, 500ms should be plenty */
timeout = jiffies + msecs_to_jiffies(500);
do {
udelay(100);
pci_read_config_byte(dev->pdev, GDRST, &gdrst);
} while ((gdrst & 0x1) && time_after(timeout, jiffies));
if (gdrst & 0x1) {
WARN(true, "i915: Failed to reset chip\n");
mutex_unlock(&dev->struct_mutex);
return -EIO;
}
} else {
DRM_ERROR("Error occurred. Don't know how to reset this chip.\n");
mutex_unlock(&dev->struct_mutex);
return -ENODEV;
}
/* Ok, now get things going again... */
/*
* Everything depends on having the GTT running, so we need to start
* there. Fortunately we don't need to do this unless we reset the
* chip at a PCI level.
*
* Next we need to restore the context, but we don't use those
* yet either...
*
* Ring buffer needs to be re-initialized in the KMS case, or if X
* was running at the time of the reset (i.e. we weren't VT
* switched away).
*/
if (drm_core_check_feature(dev, DRIVER_MODESET) ||
!dev_priv->mm.suspended) {
drm_i915_ring_buffer_t *ring = &dev_priv->ring;
struct drm_gem_object *obj = ring->ring_obj;
struct drm_i915_gem_object *obj_priv = obj->driver_private;
dev_priv->mm.suspended = 0;
/* Stop the ring if it's running. */
I915_WRITE(PRB0_CTL, 0);
I915_WRITE(PRB0_TAIL, 0);
I915_WRITE(PRB0_HEAD, 0);
/* Initialize the ring. */
I915_WRITE(PRB0_START, obj_priv->gtt_offset);
I915_WRITE(PRB0_CTL,
((obj->size - 4096) & RING_NR_PAGES) |
RING_NO_REPORT |
RING_VALID);
if (!drm_core_check_feature(dev, DRIVER_MODESET))
i915_kernel_lost_context(dev);
else {
ring->head = I915_READ(PRB0_HEAD) & HEAD_ADDR;
ring->tail = I915_READ(PRB0_TAIL) & TAIL_ADDR;
ring->space = ring->head - (ring->tail + 8);
if (ring->space < 0)
ring->space += ring->Size;
}
mutex_unlock(&dev->struct_mutex);
drm_irq_uninstall(dev);
drm_irq_install(dev);
mutex_lock(&dev->struct_mutex);
}
/*
* Display needs restore too...
*/
if (need_display)
i915_restore_display(dev);
mutex_unlock(&dev->struct_mutex);
return 0;
}
int i965_reset(struct drm_device *dev, u8 flags)
{
drm_i915_private_t *dev_priv = dev->dev_private;
unsigned long timeout;
u8 gdrst;
/*
* We really should only reset the display subsystem if we actually
* need to
*/
bool need_display = true;
mutex_lock(&dev->struct_mutex);
/*
* Clear request list
*/
i915_gem_retire_requests(dev, &dev_priv->render_ring);
if (need_display)
i915_save_display(dev);
if (IS_I965G(dev) || IS_G4X(dev)) {
/*
* Set the domains we want to reset, then the reset bit (bit 0).
* Clear the reset bit after a while and wait for hardware status
* bit (bit 1) to be set
*/
pci_read_config_byte(dev->pdev, GDRST, &gdrst);
pci_write_config_byte(dev->pdev, GDRST, gdrst | flags | ((flags == GDRST_FULL) ? 0x1 : 0x0));
udelay(50);
pci_write_config_byte(dev->pdev, GDRST, gdrst & 0xfe);
/* ...we don't want to loop forever though, 500ms should be plenty */
timeout = jiffies + msecs_to_jiffies(500);
do {
udelay(100);
pci_read_config_byte(dev->pdev, GDRST, &gdrst);
} while ((gdrst & 0x1) && time_after(timeout, jiffies));
if (gdrst & 0x1) {
WARN(true, "i915: Failed to reset chip\n");
mutex_unlock(&dev->struct_mutex);
return -EIO;
}
} else {
DRM_ERROR("Error occurred. Don't know how to reset this chip.\n");
mutex_unlock(&dev->struct_mutex);
return -ENODEV;
}
/* Ok, now get things going again... */
/*
* Everything depends on having the GTT running, so we need to start
* there. Fortunately we don't need to do this unless we reset the
* chip at a PCI level.
*
* Next we need to restore the context, but we don't use those
* yet either...
*
* Ring buffer needs to be re-initialized in the KMS case, or if X
* was running at the time of the reset (i.e. we weren't VT
* switched away).
*/
if (drm_core_check_feature(dev, DRIVER_MODESET) ||
!dev_priv->mm.suspended) {
struct intel_ring_buffer *ring = &dev_priv->render_ring;
dev_priv->mm.suspended = 0;
ring->init(dev, ring);
mutex_unlock(&dev->struct_mutex);
drm_irq_uninstall(dev);
drm_irq_install(dev);
mutex_lock(&dev->struct_mutex);
}
/*
* Display needs restore too...
*/
if (need_display)
i915_restore_display(dev);
mutex_unlock(&dev->struct_mutex);
return 0;
}
