Intel Client DGFX card supports D3Cold with two option.
D3Cold-off zero watt, D3Cold-VRAM Self Refresh.
i915 requires to evict the lmem objects to smem in order to
support D3Cold-Off, which increases i915 the suspend/resume
latency. Enabling VRAM Self Refresh feature optimize the
latency with additional power cost which required to retain
the lmem.
Adding intel_runtime_idle (runtime_idle callback) to enable
VRAM_SR, it will be used for policy to choose
between D3Cold-off vs D3Cold-VRAM_SR.
Since we have introduced i915 runtime_idle callback.
It need to be warranted that Runtime PM Core invokes runtime_idle
callback when runtime usages count becomes zero. That requires
to use pm_runtime_put instead of pm_runtime_put_autosuspend.
TODO: GT and GuC Interface state save/restore on VRAM_SR entry/exit.
v2:
- Remove drm_dbg("VRAM Self Refresh enabled"). [Jani]
Cc: Rodrigo Vivi <rodrigo.v...@intel.com>
Cc: Chris Wilson <chris.p.wil...@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gu...@intel.com>
---
drivers/gpu/drm/i915/i915_driver.c | 26 +++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_runtime_pm.c | 3 +--
2 files changed, 27 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_driver.c
b/drivers/gpu/drm/i915/i915_driver.c
index 1bc6227c0287..7357639456b5 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -1573,6 +1573,31 @@ static int i915_pm_restore(struct device *kdev)
return i915_pm_resume(kdev);
}
+static int intel_runtime_idle(struct device *kdev)
+{
+ struct drm_i915_private *i915 = kdev_to_i915(kdev);
+ int ret = 1;
+
+ if (!HAS_LMEM_SR(i915)) {
+ /*TODO: Prepare for D3Cold-Off */
+ goto out;
+ }
+
+ disable_rpm_wakeref_asserts(&i915->runtime_pm);
+
+ ret = intel_pm_vram_sr(i915, true);
+ if (!ret)
+ ret = 1;
+
+ enable_rpm_wakeref_asserts(&i915->runtime_pm);
+
+out:
+ pm_runtime_mark_last_busy(kdev);
+ pm_runtime_autosuspend(kdev);
+
+ return ret;
+}
+
static int intel_runtime_suspend(struct device *kdev)
{
struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
@@ -1758,6 +1783,7 @@ const struct dev_pm_ops i915_pm_ops = {
.restore = i915_pm_restore,
/* S0ix (via runtime suspend) event handlers */
+ .runtime_idle = intel_runtime_idle,
.runtime_suspend = intel_runtime_suspend,
.runtime_resume = intel_runtime_resume,
};
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c
b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 6ed5786bcd29..4dade7e8a795 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -492,8 +492,7 @@ static void __intel_runtime_pm_put(struct intel_runtime_pm
*rpm,
intel_runtime_pm_release(rpm, wakelock);
- pm_runtime_mark_last_busy(kdev);
- pm_runtime_put_autosuspend(kdev);
+ pm_runtime_put(kdev);
}
/**
--
2.26.2
