[PATCH] drm/komeda: Adds power management support

Lowry Li (Arm Technology China) Lowry.Li at arm.com
Fri Jun 21 03:11:22 UTC 2019


Hi Liviu,

On Thu, Jun 20, 2019 at 12:15:22AM +0800, Liviu Dudau wrote:
> Hi Lowry,
> 
> On Mon, Jun 17, 2019 at 06:55:49AM +0100, Lowry Li (Arm Technology China) wrote:
> > Adds runtime and system power management support in KMS kernel driver.
> > 
> > Depends on:
> > - https://patchwork.freedesktop.org/series/61650/
> > - https://patchwork.freedesktop.org/series/60083/
> > 
> > Signed-off-by: Lowry Li (Arm Technology China) <lowry.li at arm.com>
> > ---
> >  drivers/gpu/drm/arm/display/komeda/komeda_crtc.c |  2 +
> >  drivers/gpu/drm/arm/display/komeda/komeda_dev.c  | 30 +++++++++++++
> >  drivers/gpu/drm/arm/display/komeda/komeda_dev.h  |  2 +
> >  drivers/gpu/drm/arm/display/komeda/komeda_drv.c  | 54 ++++++++++++++++++++++--
> >  4 files changed, 85 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_crtc.c b/drivers/gpu/drm/arm/display/komeda/komeda_crtc.c
> > index 66c5e0d..1b4ea8a 100644
> > --- a/drivers/gpu/drm/arm/display/komeda/komeda_crtc.c
> > +++ b/drivers/gpu/drm/arm/display/komeda/komeda_crtc.c
> > @@ -257,6 +257,7 @@ void komeda_crtc_handle_event(struct komeda_crtc   *kcrtc,
> >  komeda_crtc_atomic_enable(struct drm_crtc *crtc,
> >  			  struct drm_crtc_state *old)
> >  {
> > +	pm_runtime_get_sync(crtc->dev->dev);
> >  	komeda_crtc_prepare(to_kcrtc(crtc));
> >  	drm_crtc_vblank_on(crtc);
> >  	komeda_crtc_do_flush(crtc, old);
> > @@ -330,6 +331,7 @@ void komeda_crtc_handle_event(struct komeda_crtc   *kcrtc,
> >  
> >  	drm_crtc_vblank_off(crtc);
> >  	komeda_crtc_unprepare(kcrtc);
> > +	pm_runtime_put(crtc->dev->dev);
> >  }
> >  
> >  static void
> > diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c
> > index 405c64d..edd0943 100644
> > --- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c
> > +++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c
> > @@ -308,3 +308,33 @@ void komeda_dev_destroy(struct komeda_dev *mdev)
> >  
> >  	devm_kfree(dev, mdev);
> >  }
> > +
> > +int komeda_dev_resume(struct komeda_dev *mdev)
> > +{
> > +	int ret = 0;
> > +
> > +	if (mdev->iommu && mdev->funcs->connect_iommu) {
> > +		ret = mdev->funcs->connect_iommu(mdev);
> > +		if (ret < 0) {
> > +			DRM_ERROR("connect iommu failed.\n");
> > +			return ret;
> > +		}
> > +	}
> > +
> > +	return mdev->funcs->enable_irq(mdev);
> > +}
> > +
> > +int komeda_dev_suspend(struct komeda_dev *mdev)
> > +{
> > +	int ret = 0;
> > +
> > +	if (mdev->iommu && mdev->funcs->disconnect_iommu) {
> > +		ret = mdev->funcs->disconnect_iommu(mdev);
> > +		if (ret < 0) {
> > +			DRM_ERROR("disconnect iommu failed.\n");
> > +			return ret;
> > +		}
> > +	}
> > +
> > +	return mdev->funcs->disable_irq(mdev);
> > +}
> > diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.h b/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
> > index d1c86b6..096f9f7 100644
> > --- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
> > +++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.h
> > @@ -207,4 +207,6 @@ struct komeda_dev {
> >  
> >  struct komeda_dev *dev_to_mdev(struct device *dev);
> >  
> > +int komeda_dev_resume(struct komeda_dev *mdev);
> > +int komeda_dev_suspend(struct komeda_dev *mdev);
> >  #endif /*_KOMEDA_DEV_H_*/
> > diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
> > index cfa5068..aa4cef1 100644
> > --- a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
> > +++ b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c
> > @@ -8,6 +8,7 @@
> >  #include <linux/kernel.h>
> >  #include <linux/platform_device.h>
> >  #include <linux/component.h>
> > +#include <linux/pm_runtime.h>
> >  #include <drm/drm_of.h>
> >  #include "komeda_dev.h"
> >  #include "komeda_kms.h"
> > @@ -32,6 +33,9 @@ static void komeda_unbind(struct device *dev)
> >  		return;
> >  
> >  	komeda_kms_detach(mdrv->kms);
> > +
> > +	pm_runtime_disable(dev);
> > +
> >  	komeda_dev_destroy(mdrv->mdev);
> >  
> >  	dev_set_drvdata(dev, NULL);
> > @@ -52,6 +56,9 @@ static int komeda_bind(struct device *dev)
> >  		err = PTR_ERR(mdrv->mdev);
> >  		goto free_mdrv;
> >  	}
> > +	dev_set_drvdata(dev, mdrv);
> > +
> > +	pm_runtime_enable(dev);
> >  
> >  	mdrv->kms = komeda_kms_attach(mdrv->mdev);
> >  	if (IS_ERR(mdrv->kms)) {
> > @@ -59,11 +66,10 @@ static int komeda_bind(struct device *dev)
> >  		goto destroy_mdev;
> >  	}
> >  
> > -	dev_set_drvdata(dev, mdrv);
> > -
> >  	return 0;
> >  
> >  destroy_mdev:
> > +	pm_runtime_disable(dev);
> >  	komeda_dev_destroy(mdrv->mdev);
> >  
> >  free_mdrv:
> > @@ -134,13 +140,55 @@ static int komeda_platform_remove(struct platform_device *pdev)
> >  
> >  MODULE_DEVICE_TABLE(of, komeda_of_match);
> >  
> > +static int komeda_rt_pm_suspend(struct device *dev)
> > +{
> > +	dev_info(dev, "%s\n", __func__);
> > +	return 0;
> > +}
> > +
> > +static int komeda_rt_pm_resume(struct device *dev)
> > +{
> > +	dev_info(dev, "%s\n", __func__);
> > +	return 0;
> > +}
> 
> 
> Useful only for debugging? I think you've missed an opportunity here to turn
> off clocks and disable interrupts.
Since we have unified mclk/pclk/pipeline->aclk to one mclk, which will
be turned on/off when crtc atomic enable/disable, no need to do those
here. So runtime pm resume and suspend will be removed.
> > +
> > +static int __maybe_unused komeda_pm_suspend(struct device *dev)
> > +{
> > +	struct komeda_drv *mdrv = dev_get_drvdata(dev);
> > +	struct drm_device *drm = &mdrv->kms->base;
> > +	int res;
> > +
> > +	dev_info(dev, "%s\n", __func__);
> > +	res = drm_mode_config_helper_suspend(drm);
> > +
> > +	komeda_dev_suspend(mdrv->mdev);
> > +
> > +	return res;
> > +}
> > +
> > +static int __maybe_unused komeda_pm_resume(struct device *dev)
> > +{
> > +	struct komeda_drv *mdrv = dev_get_drvdata(dev);
> > +	struct drm_device *drm = &mdrv->kms->base;
> > +
> > +	dev_info(dev, "%s\n", __func__);
> 
> I don't see the point of printing all these message on suspend/resume. Please
> convert them to DRM_DEBUG() if you want to have some sort of notices in the
> kernel log, otherwise please remove them.
>
> Best regards,
> Liviu
Yes, will remove them. Thanks a lot.

Best regards,
Lowry 
> 
> > +	komeda_dev_resume(mdrv->mdev);
> > +
> > +	return drm_mode_config_helper_resume(drm);
> > +}
> > +
> > +static const struct dev_pm_ops komeda_pm_ops = {
> > +	SET_SYSTEM_SLEEP_PM_OPS(komeda_pm_suspend, komeda_pm_resume)
> > +	SET_RUNTIME_PM_OPS(komeda_rt_pm_suspend, komeda_rt_pm_resume, NULL)
> > +};
> > +
> >  static struct platform_driver komeda_platform_driver = {
> >  	.probe	= komeda_platform_probe,
> >  	.remove	= komeda_platform_remove,
> >  	.driver	= {
> >  		.name = "komeda",
> >  		.of_match_table	= komeda_of_match,
> > -		.pm = NULL,
> > +		.pm = &komeda_pm_ops,
> >  	},
> >  };
> >  
> > -- 
> > 1.9.1
> > 
> 
> -- 
> ====================
> | I would like to |
> | fix the world,  |
> | but they're not |
> | giving me the   |
>  \ source code!  /
>   ---------------
>     ¯\_(ツ)_/¯

-- 
Regards,
Lowry


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