[PATCH 02/11] drm/i915: put runtime PM only at the end of intel_mark_idle

Paulo Zanoni
2014-02-21T16:52:52Z

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

Because intel_mark_idle still touches some registers: it needs the
machine to be awake. If you set both the autosuspend and PC8 delays to
zero, you can get a "Device suspended" WARN when gen6_rps_idle touches
registers.

This is not easy to reproduce, but happens once in a while when
running pm_pc8.

Testcase: igt/pm_pc8
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index dd416f2..10ec401 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -8210,10 +8210,8 @@ void intel_mark_idle(struct drm_device *dev)

dev_priv->mm.busy = false;

- hsw_package_c8_gpu_idle(dev_priv);
-
if (!i915.powersave)
- return;
+ goto out;

list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
if (!crtc->fb)
@@ -8224,6 +8222,9 @@ void intel_mark_idle(struct drm_device *dev)

if (INTEL_INFO(dev)->gen >= 6)
gen6_rps_idle(dev->dev_private);
+
+out:
+ hsw_package_c8_gpu_idle(dev_priv);
}

void intel_mark_fb_busy(struct drm_i915_gem_object *obj,
--
1.8.5.3