diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c index 9069f284495f..c0ce5e44ac3a 100644 --- a/drivers/gpu/drm/i915/i915_debugfs.c +++ b/drivers/gpu/drm/i915/i915_debugfs.c @@ -1217,6 +1217,18 @@ static int i915_context_status(struct seq_file *m, void *unused) return 0; } +static int i915_gen6_forcewake_count_info(struct seq_file *m, void *data) +{ + struct drm_info_node *node = (struct drm_info_node *) m->private; + struct drm_device *dev = node->minor->dev; + struct drm_i915_private *dev_priv = dev->dev_private; + + seq_printf(m, "forcewake count = %d\n", + atomic_read(&dev_priv->forcewake_count)); + + return 0; +} + static int i915_wedged_open(struct inode *inode, struct file *filp) @@ -1319,6 +1331,67 @@ static int i915_wedged_create(struct dentry *root, struct drm_minor *minor) return drm_add_fake_info_node(minor, ent, &i915_wedged_fops); } +static int i915_forcewake_open(struct inode *inode, struct file *file) +{ + struct drm_device *dev = inode->i_private; + struct drm_i915_private *dev_priv = dev->dev_private; + int ret; + + if (!IS_GEN6(dev)) + return 0; + + ret = mutex_lock_interruptible(&dev->struct_mutex); + if (ret) + return ret; + gen6_gt_force_wake_get(dev_priv); + mutex_unlock(&dev->struct_mutex); + + return 0; +} + +int i915_forcewake_release(struct inode *inode, struct file *file) +{ + struct drm_device *dev = inode->i_private; + struct drm_i915_private *dev_priv = dev->dev_private; + + if (!IS_GEN6(dev)) + return 0; + + /* + * It's bad that we can potentially hang userspace if struct_mutex gets + * forever stuck. However, if we cannot acquire this lock it means that + * almost certainly the driver has hung, is not unload-able. Therefore + * hanging here is probably a minor inconvenience not to be seen my + * almost every user. + */ + mutex_lock(&dev->struct_mutex); + gen6_gt_force_wake_put(dev_priv); + mutex_unlock(&dev->struct_mutex); + + return 0; +} + +static const struct file_operations i915_forcewake_fops = { + .owner = THIS_MODULE, + .open = i915_forcewake_open, + .release = i915_forcewake_release, +}; + +static int i915_forcewake_create(struct dentry *root, struct drm_minor *minor) +{ + struct drm_device *dev = minor->dev; + struct dentry *ent; + + ent = debugfs_create_file("i915_forcewake_user", + S_IRWXU, + root, dev, + &i915_forcewake_fops); + if (IS_ERR(ent)) + return PTR_ERR(ent); + + return 0; +} + static struct drm_info_list i915_debugfs_list[] = { {"i915_capabilities", i915_capabilities, 0}, {"i915_gem_objects", i915_gem_object_info, 0}, @@ -1356,6 +1429,7 @@ static struct drm_info_list i915_debugfs_list[] = { {"i915_opregion", i915_opregion, 0}, {"i915_gem_framebuffer", i915_gem_framebuffer_info, 0}, {"i915_context_status", i915_context_status, 0}, + {"i915_gen6_forcewake_count", i915_gen6_forcewake_count_info, 0}, }; #define I915_DEBUGFS_ENTRIES ARRAY_SIZE(i915_debugfs_list) @@ -1367,6 +1441,10 @@ int i915_debugfs_init(struct drm_minor *minor) if (ret) return ret; + ret = i915_forcewake_create(minor->debugfs_root, minor); + if (ret) + return ret; + return drm_debugfs_create_files(i915_debugfs_list, I915_DEBUGFS_ENTRIES, minor->debugfs_root, minor); @@ -1376,6 +1454,8 @@ void i915_debugfs_cleanup(struct drm_minor *minor) { drm_debugfs_remove_files(i915_debugfs_list, I915_DEBUGFS_ENTRIES, minor); + drm_debugfs_remove_files((struct drm_info_list *) &i915_forcewake_fops, + 1, minor); drm_debugfs_remove_files((struct drm_info_list *) &i915_wedged_fops, 1, minor); }