Commit 889a2b06 authored by AngeloGioacchino Del Regno's avatar AngeloGioacchino Del Regno Committed by Steven Price
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drm/panfrost: Implement ability to turn on/off regulators in suspend 



Some platforms/SoCs can power off the GPU entirely by completely cutting
off power, greatly enhancing battery time during system suspend: add a
new pm_feature GPU_PM_VREG_OFF to allow turning off the GPU regulators
during full suspend only on selected platforms.

Signed-off-by: default avatarAngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: default avatarSteven Price <steven.price@arm.com>
Signed-off-by: default avatarSteven Price <steven.price@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231109102543.42971-6-angelogioacchino.delregno@collabora.com
parent 32f175d4

drivers/gpu/drm/panfrost/panfrost_device.c

+18 −1
Original line number Diff line number Diff line
@@ -431,10 +431,21 @@ static int panfrost_device_resume(struct device *dev) 
	struct panfrost_device *pfdev = dev_get_drvdata(dev);

	int ret;



	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF)) {

		unsigned long freq = pfdev->pfdevfreq.fast_rate;

		struct dev_pm_opp *opp;



		opp = dev_pm_opp_find_freq_ceil(dev, &freq);

		if (IS_ERR(opp))

			return PTR_ERR(opp);

		dev_pm_opp_set_opp(dev, opp);

		dev_pm_opp_put(opp);

	}



	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS)) {

		ret = clk_enable(pfdev->clock);

		if (ret)

			return ret;

			goto err_clk;



		if (pfdev->bus_clock) {

			ret = clk_enable(pfdev->bus_clock);
@@ -455,6 +466,9 @@ static int panfrost_device_resume(struct device *dev) 
err_bus_clk:

	if (pfdev->comp->pm_features & BIT(GPU_PM_CLK_DIS))

		clk_disable(pfdev->clock);

err_clk:

	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF))

		dev_pm_opp_set_opp(dev, NULL);

	return ret;

}
@@ -474,6 +488,9 @@ static int panfrost_device_suspend(struct device *dev) 
		clk_disable(pfdev->clock);

	}



	if (pfdev->comp->pm_features & BIT(GPU_PM_VREG_OFF))

		dev_pm_opp_set_opp(dev, NULL);



	return 0;

}

drivers/gpu/drm/panfrost/panfrost_device.h

+2 −0
Original line number Diff line number Diff line
@@ -28,9 +28,11 @@ struct panfrost_perfcnt; 
/**

 * enum panfrost_gpu_pm - Supported kernel power management features

 * @GPU_PM_CLK_DIS:  Allow disabling clocks during system suspend

 * @GPU_PM_VREG_OFF: Allow turning off regulators during system suspend

 */

enum panfrost_gpu_pm {

	GPU_PM_CLK_DIS,

	GPU_PM_VREG_OFF,

};



struct panfrost_features {