Re: [Intel-gfx] [PATCH] drm/i915/dgfx: Enable d3cold at s2idle

[Rodrigo Vivi <rodrigo.vivi@intel.com>]

On Mon, Aug 14, 2023 at 04:34:18PM +0530, Anshuman Gupta wrote:
> System wide suspend already has support for lmem save/restore during
> suspend therefore enabling d3cold for s2idle and keepng it disable for
> runtime PM.(Refer below commit for d3cold runtime PM disable justification)
> 'commit 66eb93e71a7a ("drm/i915/dgfx: Keep PCI autosuspend control
> 'on' by default on all dGPU")'
> 
> It will reduce the DG2 Card power consumption to ~0 Watt
> for s2idle power KPI.
> 
> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/8755
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

> ---
>  drivers/gpu/drm/i915/i915_driver.c | 33 ++++++++++++++++--------------
>  1 file changed, 18 insertions(+), 15 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
> index b870c0df081a..ec4d26b3c17c 100644
> --- a/drivers/gpu/drm/i915/i915_driver.c
> +++ b/drivers/gpu/drm/i915/i915_driver.c
> @@ -443,7 +443,6 @@ static int i915_pcode_init(struct drm_i915_private *i915)
>  static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
>  {
>  	struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
> -	struct pci_dev *root_pdev;
>  	int ret;
>  
>  	if (i915_inject_probe_failure(dev_priv))
> @@ -557,15 +556,6 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
>  
>  	intel_bw_init_hw(dev_priv);
>  
> -	/*
> -	 * FIXME: Temporary hammer to avoid freezing the machine on our DGFX
> -	 * This should be totally removed when we handle the pci states properly
> -	 * on runtime PM and on s2idle cases.
> -	 */
> -	root_pdev = pcie_find_root_port(pdev);
> -	if (root_pdev)
> -		pci_d3cold_disable(root_pdev);
> -
>  	return 0;
>  
>  err_opregion:
> @@ -591,7 +581,6 @@ static int i915_driver_hw_probe(struct drm_i915_private *dev_priv)
>  static void i915_driver_hw_remove(struct drm_i915_private *dev_priv)
>  {
>  	struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
> -	struct pci_dev *root_pdev;
>  
>  	i915_perf_fini(dev_priv);
>  
> @@ -599,10 +588,6 @@ static void i915_driver_hw_remove(struct drm_i915_private *dev_priv)
>  
>  	if (pdev->msi_enabled)
>  		pci_disable_msi(pdev);
> -
> -	root_pdev = pcie_find_root_port(pdev);
> -	if (root_pdev)
> -		pci_d3cold_enable(root_pdev);
>  }
>  
>  /**
> @@ -1519,6 +1504,8 @@ static int intel_runtime_suspend(struct device *kdev)
>  {
>  	struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
>  	struct intel_runtime_pm *rpm = &dev_priv->runtime_pm;
> +	struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
> +	struct pci_dev *root_pdev;
>  	struct intel_gt *gt;
>  	int ret, i;
>  
> @@ -1570,6 +1557,15 @@ static int intel_runtime_suspend(struct device *kdev)
>  		drm_err(&dev_priv->drm,
>  			"Unclaimed access detected prior to suspending\n");
>  
> +	/*
> +	 * FIXME: Temporary hammer to avoid freezing the machine on our DGFX
> +	 * This should be totally removed when we handle the pci states properly
> +	 * on runtime PM.
> +	 */
> +	root_pdev = pcie_find_root_port(pdev);
> +	if (root_pdev)
> +		pci_d3cold_disable(root_pdev);
> +
>  	rpm->suspended = true;
>  
>  	/*
> @@ -1608,6 +1604,8 @@ static int intel_runtime_resume(struct device *kdev)
>  {
>  	struct drm_i915_private *dev_priv = kdev_to_i915(kdev);
>  	struct intel_runtime_pm *rpm = &dev_priv->runtime_pm;
> +	struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev);
> +	struct pci_dev *root_pdev;
>  	struct intel_gt *gt;
>  	int ret, i;
>  
> @@ -1621,6 +1619,11 @@ static int intel_runtime_resume(struct device *kdev)
>  
>  	intel_opregion_notify_adapter(dev_priv, PCI_D0);
>  	rpm->suspended = false;
> +
> +	root_pdev = pcie_find_root_port(pdev);
> +	if (root_pdev)
> +		pci_d3cold_enable(root_pdev);
> +
>  	if (intel_uncore_unclaimed_mmio(&dev_priv->uncore))
>  		drm_dbg(&dev_priv->drm,
>  			"Unclaimed access during suspend, bios?\n");
> -- 
> 2.25.1
>