drm/i915: don't rewrite the GTT on resume v4

The BIOS shouldn't be touching this memory across suspend/resume, so
just leave it alone.  This saves us ~6ms on resume on my T420 (retested
with write combined PTEs).

v2: change gtt restore default on pre-gen4 (Chris)
    move needs_gtt_restore flag into dev_priv
v3: make sure we restore GTT on resume from hibernate (Daniel)
    use opregion support as the cutoff for restore from resume (Chris)
v4: use a better check for opregion (Chris)

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Kill the needs_gtt_restore indirection and check directly for
OpRegion. Also explain in a comment what's going on.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Jesse Barnes 2012-11-02 11:14:02 -07:00 committed by Daniel Vetter
parent 4fc688ce79
commit 1abd02e2dd
2 changed files with 33 additions and 11 deletions

View File

@ -1594,7 +1594,6 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
intel_setup_gmbus(dev);
intel_opregion_setup(dev);
/* Make sure the bios did its job and set up vital registers */
intel_setup_bios(dev);
i915_gem_load(dev);

View File

@ -537,19 +537,11 @@ void intel_console_resume(struct work_struct *work)
console_unlock();
}
static int i915_drm_thaw(struct drm_device *dev)
static int __i915_drm_thaw(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
int error = 0;
intel_gt_reset(dev);
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
mutex_lock(&dev->struct_mutex);
i915_gem_restore_gtt_mappings(dev);
mutex_unlock(&dev->struct_mutex);
}
i915_restore_state(dev);
intel_opregion_setup(dev);
@ -588,8 +580,26 @@ static int i915_drm_thaw(struct drm_device *dev)
return error;
}
static int i915_drm_thaw(struct drm_device *dev)
{
int error = 0;
intel_gt_reset(dev);
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
mutex_lock(&dev->struct_mutex);
i915_gem_restore_gtt_mappings(dev);
mutex_unlock(&dev->struct_mutex);
}
__i915_drm_thaw(dev);
return error;
}
int i915_resume(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
int ret;
if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
@ -600,7 +610,20 @@ int i915_resume(struct drm_device *dev)
pci_set_master(dev->pdev);
ret = i915_drm_thaw(dev);
intel_gt_reset(dev);
/*
* Platforms with opregion should have sane BIOS, older ones (gen3 and
* earlier) need this since the BIOS might clear all our scratch PTEs.
*/
if (drm_core_check_feature(dev, DRIVER_MODESET) &&
!dev_priv->opregion.header) {
mutex_lock(&dev->struct_mutex);
i915_gem_restore_gtt_mappings(dev);
mutex_unlock(&dev->struct_mutex);
}
ret = __i915_drm_thaw(dev);
if (ret)
return ret;