From: Chris Wilson chris@chris-wilson.co.uk
[ Upstream commit 7ed43df720c007d60bee6d81da07bcdc7e4a55ae ]
If we fail during GEM initialisation, we scrub the HW state by performing a device level GPU resuet. However, we want to leave the system in a usable state (with functioning KMS but no GEM) so after scrubbing the HW state, we need to restore some sane defaults and re-enable the low-level common parts of the GPU (such as the GMCH).
v2: Restore GTT entries.
Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Link: https://patchwork.freedesktop.org/patch/msgid/20180726085033.4044-2-chris@ch... Reviewed-by: Michał Winiarski michal.winiarski@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/i915/i915_gem.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 03cda197fb6b8..5019dfd8bcf16 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -5595,6 +5595,8 @@ int i915_gem_init(struct drm_i915_private *dev_priv) i915_gem_cleanup_userptr(dev_priv);
if (ret == -EIO) { + mutex_lock(&dev_priv->drm.struct_mutex); + /* * Allow engine initialisation to fail by marking the GPU as * wedged. But we only want to do this where the GPU is angry, @@ -5605,7 +5607,14 @@ int i915_gem_init(struct drm_i915_private *dev_priv) "Failed to initialize GPU, declaring it wedged!\n"); i915_gem_set_wedged(dev_priv); } - ret = 0; + + /* Minimal basic recovery for KMS */ + ret = i915_ggtt_enable_hw(dev_priv); + i915_gem_restore_gtt_mappings(dev_priv); + i915_gem_restore_fences(dev_priv); + intel_init_clock_gating(dev_priv); + + mutex_unlock(&dev_priv->drm.struct_mutex); }
i915_gem_drain_freed_objects(dev_priv);