[PATCH 1/3] drm/i915: fix cursor handling when runtime suspended

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

If we're runtime suspended and try to use the cursor interfaces, we
will get a lot of WARNs saying we did the wrong thing.

For intel_crtc_update_cursor(), all we need to do is return if the
CRTC is not active, since writing the registers won't really have any
effect if the screen is not visible, and we will write the registers
later when enabling the screen.

For intel_crtc_cursor_set_obj(), we just need to wake up the hardware
then pinning the display plane.

v2: - Narrow the put/get calls on intel_crtc_cursor_set_obj() (Daniel)

Testcase: igt/pm_rpm/cursor
Testcase: igt/pm_rpm/cursor-dpms
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=81645
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 1edfd1a..f1a9b5c 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8144,6 +8144,9 @@ static void intel_crtc_update_cursor(struct drm_crtc *crtc,
 	if (base == 0 && intel_crtc->cursor_base == 0)
 		return;
 
+	if (!intel_crtc->active)
+		return;
+
 	I915_WRITE(CURPOS(pipe), pos);
 
 	if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev) || IS_BROADWELL(dev))
@@ -8217,7 +8220,9 @@ static int intel_crtc_cursor_set_obj(struct drm_crtc *crtc,
 		if (need_vtd_wa(dev))
 			alignment = 64*1024;
 
+		intel_runtime_pm_get(dev_priv);
 		ret = i915_gem_object_pin_to_display_plane(obj, alignment, NULL);
+		intel_runtime_pm_put(dev_priv);
 		if (ret) {
 			DRM_DEBUG_KMS("failed to move cursor bo into the GTT\n");
 			goto fail_locked;
-- 
2.0.1