[PATCH v13 07/19] drm/i915: Create GEM runtime resume helper and handle GEM runtime suspend error

[Sagar Arun Kamble]

These changes are preparation to handle GuC suspend/resume. Prepared
helper i915_gem_runtime_resume to reinitialize suspended gem setup.
Returning status from i915_gem_runtime_suspend.
This will be placeholder for handling any errors from uC suspend/resume
in upcoming patches. Restructured the suspend/resume routines w.r.t setup
creation and rollback order.
This also fixes issue of ordering of i915_gem_runtime_resume with
intel_runtime_pm_enable_interrupts.

v2: Fixed return from intel_runtime_resume. (Michał Winiarski)

v3: Not returning status from gem_runtime_resume. (Chris)

v4: Refined return from i915_gem_runtime_suspend. (Michal Wajdeczko)

v5: Updated jump labels. (Chris, Joonas) Removed invalid comments about
gem_runtime_resume and removed updates to i915_gem_resume. (Chris)

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
Cc: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Imre Deak <imre.deak at intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko at intel.com>
Cc: Michał Winiarski <michal.winiarski at intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c | 28 +++++++++++++++-------------
 drivers/gpu/drm/i915/i915_drv.h |  3 ++-
 drivers/gpu/drm/i915/i915_gem.c | 10 +++++++++-
 3 files changed, 26 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index a500a81..7b043d7 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -2516,7 +2516,9 @@ static int intel_runtime_suspend(struct device *kdev)
 	 * We are safe here against re-faults, since the fault handler takes
 	 * an RPM reference.
 	 */
-	i915_gem_runtime_suspend(dev_priv);
+	ret = i915_gem_runtime_suspend(dev_priv);
+	if (ret)
+		goto err_gem;
 
 	intel_guc_suspend(&dev_priv->guc);
 
@@ -2534,11 +2536,7 @@ static int intel_runtime_suspend(struct device *kdev)
 
 	if (ret) {
 		DRM_ERROR("Runtime suspend failed, disabling it (%d)\n", ret);
-		intel_runtime_pm_enable_interrupts(dev_priv);
-
-		enable_rpm_wakeref_asserts(dev_priv);
-
-		return ret;
+		goto err_disable;
 	}
 
 	intel_uncore_suspend(dev_priv);
@@ -2581,6 +2579,15 @@ static int intel_runtime_suspend(struct device *kdev)
 
 	DRM_DEBUG_KMS("Device suspended\n");
 	return 0;
+
+err_disable:
+	intel_runtime_pm_enable_interrupts(dev_priv);
+	intel_guc_resume(&dev_priv->guc);
+	i915_gem_runtime_resume(dev_priv);
+
+err_gem:
+	enable_rpm_wakeref_asserts(dev_priv);
+	return ret;
 }
 
 static int intel_runtime_resume(struct device *kdev)
@@ -2617,13 +2624,6 @@ static int intel_runtime_resume(struct device *kdev)
 		ret = vlv_resume_prepare(dev_priv, true);
 	}
 
-	/*
-	 * No point of rolling back things in case of an error, as the best
-	 * we can do is to hope that things will still work (and disable RPM).
-	 */
-	i915_gem_init_swizzling(dev_priv);
-	i915_gem_restore_fences(dev_priv);
-
 	intel_runtime_pm_enable_interrupts(dev_priv);
 
 	/*
@@ -2636,6 +2636,8 @@ static int intel_runtime_resume(struct device *kdev)
 
 	intel_enable_ipc(dev_priv);
 
+	i915_gem_runtime_resume(dev_priv);
+
 	enable_rpm_wakeref_asserts(dev_priv);
 
 	if (ret)
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 770305b..bc21da2 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3512,7 +3512,8 @@ struct i915_vma * __must_check
 int i915_gem_object_unbind(struct drm_i915_gem_object *obj);
 void i915_gem_release_mmap(struct drm_i915_gem_object *obj);
 
-void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv);
+int i915_gem_runtime_suspend(struct drm_i915_private *dev_priv);
+void i915_gem_runtime_resume(struct drm_i915_private *dev_priv);
 
 static inline int __sg_page_count(const struct scatterlist *sg)
 {
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 276166d..facf681 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2053,7 +2053,7 @@ static void __i915_gem_object_release_mmap(struct drm_i915_gem_object *obj)
 	intel_runtime_pm_put(i915);
 }
 
-void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv)
+int i915_gem_runtime_suspend(struct drm_i915_private *dev_priv)
 {
 	struct drm_i915_gem_object *obj, *on;
 	int i;
@@ -2093,6 +2093,14 @@ void i915_gem_runtime_suspend(struct drm_i915_private *dev_priv)
 		GEM_BUG_ON(i915_vma_has_userfault(reg->vma));
 		reg->dirty = true;
 	}
+
+	return 0;
+}
+
+void i915_gem_runtime_resume(struct drm_i915_private *dev_priv)
+{
+	i915_gem_init_swizzling(dev_priv);
+	i915_gem_restore_fences(dev_priv);
 }
 
 static int i915_gem_object_create_mmap_offset(struct drm_i915_gem_object *obj)
-- 
1.9.1