Commit 80ef351c authored by Dmitry Osipenko's avatar Dmitry Osipenko Committed by Thierry Reding
Browse files

soc/tegra: regulators: Prepare for suspend 

Depending on hardware version, Tegra SoC may require a higher voltages
during resume from system suspend, otherwise hardware will crash. Set
SoC voltages to a nominal levels during suspend.

Link: https://lore.kernel.org/all/a8280b5b-7347-8995-c97b-10b798cdf057@gmail.com/


Reviewed-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarDmitry Osipenko <digetx@gmail.com>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent 88724b78

drivers/soc/tegra/regulators-tegra20.c

+99 −0
Original line number Diff line number Diff line
@@ -16,7 +16,9 @@ 
#include <linux/regulator/coupler.h>

#include <linux/regulator/driver.h>

#include <linux/regulator/machine.h>

#include <linux/suspend.h>



#include <soc/tegra/fuse.h>

#include <soc/tegra/pmc.h>



struct tegra_regulator_coupler {
@@ -25,9 +27,12 @@ struct tegra_regulator_coupler { 
	struct regulator_dev *cpu_rdev;

	struct regulator_dev *rtc_rdev;

	struct notifier_block reboot_notifier;

	struct notifier_block suspend_notifier;

	int core_min_uV, cpu_min_uV;

	bool sys_reboot_mode_req;

	bool sys_reboot_mode;

	bool sys_suspend_mode_req;

	bool sys_suspend_mode;

};



static inline struct tegra_regulator_coupler *
@@ -105,6 +110,28 @@ static int tegra20_core_rtc_max_spread(struct regulator_dev *core_rdev, 
	return 150000;

}



static int tegra20_cpu_nominal_uV(void)

{

	switch (tegra_sku_info.soc_speedo_id) {

	case 0:

		return 1100000;

	case 1:

		return 1025000;

	default:

		return 1125000;

	}

}



static int tegra20_core_nominal_uV(void)

{

	switch (tegra_sku_info.soc_speedo_id) {

	default:

		return 1225000;

	case 2:

		return 1300000;

	}

}



static int tegra20_core_rtc_update(struct tegra_regulator_coupler *tegra,

				   struct regulator_dev *core_rdev,

				   struct regulator_dev *rtc_rdev,
@@ -144,6 +171,11 @@ static int tegra20_core_rtc_update(struct tegra_regulator_coupler *tegra, 
	if (err)

		return err;



	/* prepare voltage level for suspend */

	if (tegra->sys_suspend_mode)

		core_min_uV = clamp(tegra20_core_nominal_uV(),

				    core_min_uV, core_max_uV);



	core_uV = regulator_get_voltage_rdev(core_rdev);

	if (core_uV < 0)

		return core_uV;
@@ -279,6 +311,11 @@ static int tegra20_cpu_voltage_update(struct tegra_regulator_coupler *tegra, 
	if (tegra->sys_reboot_mode)

		cpu_min_uV = max(cpu_min_uV, tegra->cpu_min_uV);



	/* prepare voltage level for suspend */

	if (tegra->sys_suspend_mode)

		cpu_min_uV = clamp(tegra20_cpu_nominal_uV(),

				   cpu_min_uV, cpu_max_uV);



	if (cpu_min_uV > cpu_uV) {

		err = tegra20_core_rtc_update(tegra, core_rdev, rtc_rdev,

					      cpu_uV, cpu_min_uV);
@@ -320,6 +357,7 @@ static int tegra20_regulator_balance_voltage(struct regulator_coupler *coupler, 
	}



	tegra->sys_reboot_mode = READ_ONCE(tegra->sys_reboot_mode_req);

	tegra->sys_suspend_mode = READ_ONCE(tegra->sys_suspend_mode_req);



	if (rdev == cpu_rdev)

		return tegra20_cpu_voltage_update(tegra, cpu_rdev,
@@ -334,6 +372,63 @@ static int tegra20_regulator_balance_voltage(struct regulator_coupler *coupler, 
	return -EPERM;

}



static int tegra20_regulator_prepare_suspend(struct tegra_regulator_coupler *tegra,

					     bool sys_suspend_mode)

{

	int err;



	if (!tegra->core_rdev || !tegra->rtc_rdev || !tegra->cpu_rdev)

		return 0;



	/*

	 * All power domains are enabled early during resume from suspend

	 * by GENPD core.  Domains like VENC may require a higher voltage

	 * when enabled during resume from suspend.  This also prepares

	 * hardware for resuming from LP0.

	 */



	WRITE_ONCE(tegra->sys_suspend_mode_req, sys_suspend_mode);



	err = regulator_sync_voltage_rdev(tegra->cpu_rdev);

	if (err)

		return err;



	err = regulator_sync_voltage_rdev(tegra->core_rdev);

	if (err)

		return err;



	return 0;

}



static int tegra20_regulator_suspend(struct notifier_block *notifier,

				     unsigned long mode, void *arg)

{

	struct tegra_regulator_coupler *tegra;

	int ret = 0;



	tegra = container_of(notifier, struct tegra_regulator_coupler,

			     suspend_notifier);



	switch (mode) {

	case PM_HIBERNATION_PREPARE:

	case PM_RESTORE_PREPARE:

	case PM_SUSPEND_PREPARE:

		ret = tegra20_regulator_prepare_suspend(tegra, true);

		break;



	case PM_POST_HIBERNATION:

	case PM_POST_RESTORE:

	case PM_POST_SUSPEND:

		ret = tegra20_regulator_prepare_suspend(tegra, false);

		break;

	}



	if (ret)

		pr_err("failed to prepare regulators: %d\n", ret);



	return notifier_from_errno(ret);

}



static int tegra20_regulator_prepare_reboot(struct tegra_regulator_coupler *tegra,

					    bool sys_reboot_mode)

{
@@ -444,6 +539,7 @@ static struct tegra_regulator_coupler tegra20_coupler = { 
		.balance_voltage = tegra20_regulator_balance_voltage,

	},

	.reboot_notifier.notifier_call = tegra20_regulator_reboot,

	.suspend_notifier.notifier_call = tegra20_regulator_suspend,

};



static int __init tegra_regulator_coupler_init(void)
@@ -456,6 +552,9 @@ static int __init tegra_regulator_coupler_init(void) 
	err = register_reboot_notifier(&tegra20_coupler.reboot_notifier);

	WARN_ON(err);



	err = register_pm_notifier(&tegra20_coupler.suspend_notifier);

	WARN_ON(err);



	return regulator_coupler_register(&tegra20_coupler.coupler);

}

arch_initcall(tegra_regulator_coupler_init);

drivers/soc/tegra/regulators-tegra30.c

+122 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include <linux/regulator/coupler.h>

#include <linux/regulator/driver.h>

#include <linux/regulator/machine.h>

#include <linux/suspend.h>



#include <soc/tegra/fuse.h>

#include <soc/tegra/pmc.h>
@@ -25,9 +26,12 @@ struct tegra_regulator_coupler { 
	struct regulator_dev *core_rdev;

	struct regulator_dev *cpu_rdev;

	struct notifier_block reboot_notifier;

	struct notifier_block suspend_notifier;

	int core_min_uV, cpu_min_uV;

	bool sys_reboot_mode_req;

	bool sys_reboot_mode;

	bool sys_suspend_mode_req;

	bool sys_suspend_mode;

};



static inline struct tegra_regulator_coupler *
@@ -113,6 +117,52 @@ static int tegra30_core_cpu_limit(int cpu_uV) 
	return -EINVAL;

}



static int tegra30_cpu_nominal_uV(void)

{

	switch (tegra_sku_info.cpu_speedo_id) {

	case 10 ... 11:

		return  850000;



	case 9:

		return  912000;



	case 1 ...  3:

	case 7 ...  8:

		return 1050000;



	default:

		return 1125000;



	case  4 ...  6:

	case 12 ... 13:

		return 1237000;

	}

}



static int tegra30_core_nominal_uV(void)

{

	switch (tegra_sku_info.soc_speedo_id) {

	case 0:

		return 1200000;



	case 1:

		if (tegra_sku_info.cpu_speedo_id != 7 &&

		    tegra_sku_info.cpu_speedo_id != 8)

			return 1200000;



		fallthrough;



	case 2:

		if (tegra_sku_info.cpu_speedo_id != 13)

			return 1300000;



		return 1350000;



	default:

		return 1250000;

	}

}



static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra,

				  struct regulator_dev *cpu_rdev,

				  struct regulator_dev *core_rdev)
@@ -168,6 +218,11 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra, 
	if (err)

		return err;



	/* prepare voltage level for suspend */

	if (tegra->sys_suspend_mode)

		core_min_uV = clamp(tegra30_core_nominal_uV(),

				    core_min_uV, core_max_uV);



	core_uV = regulator_get_voltage_rdev(core_rdev);

	if (core_uV < 0)

		return core_uV;
@@ -223,6 +278,11 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra, 
	if (tegra->sys_reboot_mode)

		cpu_min_uV = max(cpu_min_uV, tegra->cpu_min_uV);



	/* prepare voltage level for suspend */

	if (tegra->sys_suspend_mode)

		cpu_min_uV = clamp(tegra30_cpu_nominal_uV(),

				   cpu_min_uV, cpu_max_uV);



	if (core_min_limited_uV > core_uV) {

		pr_err("core voltage constraint violated: %d %d %d\n",

		       core_uV, core_min_limited_uV, cpu_uV);
@@ -292,10 +352,68 @@ static int tegra30_regulator_balance_voltage(struct regulator_coupler *coupler, 
	}



	tegra->sys_reboot_mode = READ_ONCE(tegra->sys_reboot_mode_req);

	tegra->sys_suspend_mode = READ_ONCE(tegra->sys_suspend_mode_req);



	return tegra30_voltage_update(tegra, cpu_rdev, core_rdev);

}



static int tegra30_regulator_prepare_suspend(struct tegra_regulator_coupler *tegra,

					     bool sys_suspend_mode)

{

	int err;



	if (!tegra->core_rdev || !tegra->cpu_rdev)

		return 0;



	/*

	 * All power domains are enabled early during resume from suspend

	 * by GENPD core.  Domains like VENC may require a higher voltage

	 * when enabled during resume from suspend.  This also prepares

	 * hardware for resuming from LP0.

	 */



	WRITE_ONCE(tegra->sys_suspend_mode_req, sys_suspend_mode);



	err = regulator_sync_voltage_rdev(tegra->cpu_rdev);

	if (err)

		return err;



	err = regulator_sync_voltage_rdev(tegra->core_rdev);

	if (err)

		return err;



	return 0;

}



static int tegra30_regulator_suspend(struct notifier_block *notifier,

				     unsigned long mode, void *arg)

{

	struct tegra_regulator_coupler *tegra;

	int ret = 0;



	tegra = container_of(notifier, struct tegra_regulator_coupler,

			     suspend_notifier);



	switch (mode) {

	case PM_HIBERNATION_PREPARE:

	case PM_RESTORE_PREPARE:

	case PM_SUSPEND_PREPARE:

		ret = tegra30_regulator_prepare_suspend(tegra, true);

		break;



	case PM_POST_HIBERNATION:

	case PM_POST_RESTORE:

	case PM_POST_SUSPEND:

		ret = tegra30_regulator_prepare_suspend(tegra, false);

		break;

	}



	if (ret)

		pr_err("failed to prepare regulators: %d\n", ret);



	return notifier_from_errno(ret);

}



static int tegra30_regulator_prepare_reboot(struct tegra_regulator_coupler *tegra,

					    bool sys_reboot_mode)

{
@@ -395,6 +513,7 @@ static struct tegra_regulator_coupler tegra30_coupler = { 
		.balance_voltage = tegra30_regulator_balance_voltage,

	},

	.reboot_notifier.notifier_call = tegra30_regulator_reboot,

	.suspend_notifier.notifier_call = tegra30_regulator_suspend,

};



static int __init tegra_regulator_coupler_init(void)
@@ -407,6 +526,9 @@ static int __init tegra_regulator_coupler_init(void) 
	err = register_reboot_notifier(&tegra30_coupler.reboot_notifier);

	WARN_ON(err);



	err = register_pm_notifier(&tegra30_coupler.suspend_notifier);

	WARN_ON(err);



	return regulator_coupler_register(&tegra30_coupler.coupler);

}

arch_initcall(tegra_regulator_coupler_init);