drm/i915: add runtime put/get calls at the basic places

If I add code to enable runtime PM on my Haswell machine, start a
desktop environment, then enable runtime PM, these functions will
complain that they're trying to read/write registers while the
graphics card is suspended.

v2: - Simplify i915_gem_fault changes.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
[danvet: Drop the hunk in i915_hangcheck_elapsed, it's the wrong thing
to do.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

2 files changed, 27 insertions, 6 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 92149bcabe98..df83fec174e9 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1380,6 +1380,8 @@ int i915_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
         int ret = 0;
         bool write = !!(vmf->flags & FAULT_FLAG_WRITE);
 
+        intel_runtime_pm_get(dev_priv);
+
         /* We don't use vmf->pgoff since that has the fake offset */
         page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
                 PAGE_SHIFT;
@@ -1427,8 +1429,10 @@ out:
                 /* If this -EIO is due to a gpu hang, give the reset code a
                  * chance to clean up the mess. Otherwise return the proper
                  * SIGBUS. */
-                if (i915_terminally_wedged(&dev_priv->gpu_error))
-                        return VM_FAULT_SIGBUS;
+                if (i915_terminally_wedged(&dev_priv->gpu_error)) {
+                        ret = VM_FAULT_SIGBUS;
+                        break;
+                }
         case -EAGAIN:
                 /*
                  * EAGAIN means the gpu is hung and we'll wait for the error
@@ -1443,15 +1447,22 @@ out:
                  * EBUSY is ok: this just means that another thread
                  * already did the job.
                  */
-                return VM_FAULT_NOPAGE;
+                ret = VM_FAULT_NOPAGE;
+                break;
         case -ENOMEM:
-                return VM_FAULT_OOM;
+                ret = VM_FAULT_OOM;
+                break;
         case -ENOSPC:
-                return VM_FAULT_SIGBUS;
+                ret = VM_FAULT_SIGBUS;
+                break;
         default:
                 WARN_ONCE(ret, "unhandled error in i915_gem_fault: %i\n", ret);
-                return VM_FAULT_SIGBUS;
+                ret = VM_FAULT_SIGBUS;
+                break;
         }
+
+        intel_runtime_pm_put(dev_priv);
+        return ret;
 }
 
 /**
@@ -4169,6 +4180,8 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
         drm_i915_private_t *dev_priv = dev->dev_private;
         struct i915_vma *vma, *next;
 
+        intel_runtime_pm_get(dev_priv);
+
         trace_i915_gem_object_destroy(obj);
 
         if (obj->phys_obj)
@@ -4213,6 +4226,8 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
 
         kfree(obj->bit_17);
         i915_gem_object_free(obj);
+
+        intel_runtime_pm_put(dev_priv);
 }
 
 struct i915_vma *i915_gem_obj_to_vma(struct drm_i915_gem_object *obj,
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 9282b4c411f6..bceddf5a04bc 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1108,6 +1108,8 @@ i915_gem_do_execbuffer(struct drm_device *dev, void *data,
                 }
         }
 
+        intel_runtime_pm_get(dev_priv);
+
         ret = i915_mutex_lock_interruptible(dev);
         if (ret)
                 goto pre_mutex_err;
@@ -1237,6 +1239,10 @@ err:
 
 pre_mutex_err:
         kfree(cliprects);
+
+        /* intel_gpu_busy should also get a ref, so it will free when the device
+         * is really idle. */
+        intel_runtime_pm_put(dev_priv);
         return ret;
 }