-----Original Message----- From: Jani Nikula jani.nikula@linux.intel.com Sent: Thursday, June 16, 2022 8:02 PM To: Gupta, Anshuman anshuman.gupta@intel.com; intel- gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org Cc: Wilson, Chris P chris.p.wilson@intel.com; Vivi, Rodrigo rodrigo.vivi@intel.com Subject: Re: [Intel-gfx] [PATCH v2 7/9] drm/i915/rpm: Enable D3Cold VRAM SR Support
On Thu, 16 Jun 2022, Anshuman Gupta anshuman.gupta@intel.com wrote:
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: GuC interface state save/restore.
Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Chris Wilson chris.p.wilson@intel.com Signed-off-by: Anshuman Gupta anshuman.gupta@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 aa1fb15b1f11..fcff5f3fe05e 100644 --- a/drivers/gpu/drm/i915/i915_driver.c +++ b/drivers/gpu/drm/i915/i915_driver.c @@ -1557,6 +1557,31 @@ 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 *dev_priv = kdev_to_i915(kdev);
- int ret = 1;
- if (!HAS_LMEM_SR(dev_priv)) {
/*TODO: Prepare for D3Cold-Off */goto out;- }
- disable_rpm_wakeref_asserts(&dev_priv->runtime_pm);
- ret = intel_pm_vram_sr(dev_priv, true);
- if (!ret)
drm_dbg(&dev_priv->drm, "VRAM Self Refresh enabled\n");Please add the debug in the intel_pm_vram_sr() function instead.
Thanks for review comment, will fix this. Regards, Anshuman Gupta.
BR, Jani.
- enable_rpm_wakeref_asserts(&dev_priv->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); @@ -1742,6 +1767,7 @@ 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);
}
/**
-- Jani Nikula, Intel Open Source Graphics Center