NVIDIA Tegra SoCs have multiple power domains, each domain corresponds to an external SoC power rail. Core power domain covers vast majority of hardware blocks within a Tegra SoC. The voltage of a power domain should be set to a value which satisfies all devices within a power domain. Add driver for the core power domain in order to manage the voltage state of the domain. This allows us to support a system-wide DVFS on Tegra.
Signed-off-by: Dmitry Osipenko digetx@gmail.com --- drivers/soc/tegra/Kconfig | 6 ++ drivers/soc/tegra/Makefile | 1 + drivers/soc/tegra/core-power-domain.c | 125 ++++++++++++++++++++++++++ include/soc/tegra/common.h | 6 ++ 4 files changed, 138 insertions(+) create mode 100644 drivers/soc/tegra/core-power-domain.c
diff --git a/drivers/soc/tegra/Kconfig b/drivers/soc/tegra/Kconfig index bcd61ae59ba3..fccbc168dd87 100644 --- a/drivers/soc/tegra/Kconfig +++ b/drivers/soc/tegra/Kconfig @@ -16,6 +16,7 @@ config ARCH_TEGRA_2x_SOC select SOC_TEGRA_COMMON select SOC_TEGRA_FLOWCTRL select SOC_TEGRA_PMC + select SOC_TEGRA_CORE_POWER_DOMAIN select SOC_TEGRA20_VOLTAGE_COUPLER select TEGRA_TIMER help @@ -31,6 +32,7 @@ config ARCH_TEGRA_3x_SOC select SOC_TEGRA_COMMON select SOC_TEGRA_FLOWCTRL select SOC_TEGRA_PMC + select SOC_TEGRA_CORE_POWER_DOMAIN select SOC_TEGRA30_VOLTAGE_COUPLER select TEGRA_TIMER help @@ -170,3 +172,7 @@ config SOC_TEGRA20_VOLTAGE_COUPLER config SOC_TEGRA30_VOLTAGE_COUPLER bool "Voltage scaling support for Tegra30 SoCs" depends on ARCH_TEGRA_3x_SOC || COMPILE_TEST + +config SOC_TEGRA_CORE_POWER_DOMAIN + bool + select PM_GENERIC_DOMAINS diff --git a/drivers/soc/tegra/Makefile b/drivers/soc/tegra/Makefile index 9c809c1814bd..8f1294f954b4 100644 --- a/drivers/soc/tegra/Makefile +++ b/drivers/soc/tegra/Makefile @@ -7,3 +7,4 @@ obj-$(CONFIG_SOC_TEGRA_PMC) += pmc.o obj-$(CONFIG_SOC_TEGRA_POWERGATE_BPMP) += powergate-bpmp.o obj-$(CONFIG_SOC_TEGRA20_VOLTAGE_COUPLER) += regulators-tegra20.o obj-$(CONFIG_SOC_TEGRA30_VOLTAGE_COUPLER) += regulators-tegra30.o +obj-$(CONFIG_SOC_TEGRA_CORE_POWER_DOMAIN) += core-power-domain.o diff --git a/drivers/soc/tegra/core-power-domain.c b/drivers/soc/tegra/core-power-domain.c new file mode 100644 index 000000000000..7c0cec8c79fd --- /dev/null +++ b/drivers/soc/tegra/core-power-domain.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * NVIDIA Tegra SoC Core Power Domain Driver + */ + +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pm_domain.h> +#include <linux/pm_opp.h> +#include <linux/slab.h> + +#include <soc/tegra/common.h> + +static struct lock_class_key tegra_core_domain_lock_class; +static bool tegra_core_domain_state_synced; + +static int tegra_genpd_set_performance_state(struct generic_pm_domain *genpd, + unsigned int level) +{ + struct dev_pm_opp *opp; + int err; + + opp = dev_pm_opp_find_level_ceil(&genpd->dev, &level); + if (IS_ERR(opp)) { + dev_err(&genpd->dev, "failed to find OPP for level %u: %pe\n", + level, opp); + return PTR_ERR(opp); + } + + err = dev_pm_opp_set_voltage(&genpd->dev, opp); + dev_pm_opp_put(opp); + + if (err) { + dev_err(&genpd->dev, "failed to set voltage to %duV: %d\n", + level, err); + return err; + } + + return 0; +} + +static unsigned int +tegra_genpd_opp_to_performance_state(struct generic_pm_domain *genpd, + struct dev_pm_opp *opp) +{ + return dev_pm_opp_get_level(opp); +} + +static int tegra_core_domain_probe(struct platform_device *pdev) +{ + struct generic_pm_domain *genpd; + struct opp_table *opp_table; + const char *rname = "power"; + int err; + + genpd = devm_kzalloc(&pdev->dev, sizeof(*genpd), GFP_KERNEL); + if (!genpd) + return -ENOMEM; + + genpd->name = pdev->dev.of_node->name; + genpd->set_performance_state = tegra_genpd_set_performance_state; + genpd->opp_to_performance_state = tegra_genpd_opp_to_performance_state; + + opp_table = devm_pm_opp_set_regulators(&pdev->dev, &rname, 1); + if (IS_ERR(opp_table)) + return dev_err_probe(&pdev->dev, PTR_ERR(opp_table), + "failed to set OPP regulator\n"); + + err = pm_genpd_init(genpd, NULL, false); + if (err) { + dev_err(&pdev->dev, "failed to init genpd: %d\n", err); + return err; + } + + /* + * We have a "PMC -> Core" hierarchy of the power domains where + * PMC needs to resume and change performance (voltage) of the + * Core domain from the PMC GENPD on/off callbacks, hence we need + * to annotate the lock in order to remove confusion from the + * lockdep checker when a nested access happens. + */ + lockdep_set_class(&genpd->mlock, &tegra_core_domain_lock_class); + + err = of_genpd_add_provider_simple(pdev->dev.of_node, genpd); + if (err) { + dev_err(&pdev->dev, "failed to add genpd: %d\n", err); + goto remove_genpd; + } + + return 0; + +remove_genpd: + pm_genpd_remove(genpd); + + return err; +} + +bool tegra_soc_core_domain_state_synced(void) +{ + return tegra_core_domain_state_synced; +} + +static void tegra_core_domain_sync_state(struct device *dev) +{ + tegra_core_domain_state_synced = true; + + dev_pm_opp_sync_regulators(dev); +} + +static const struct of_device_id tegra_core_domain_match[] = { + { .compatible = "nvidia,tegra20-core-domain", }, + { .compatible = "nvidia,tegra30-core-domain", }, + { } +}; + +static struct platform_driver tegra_core_domain_driver = { + .driver = { + .name = "tegra-core-power", + .of_match_table = tegra_core_domain_match, + .suppress_bind_attrs = true, + .sync_state = tegra_core_domain_sync_state, + }, + .probe = tegra_core_domain_probe, +}; +builtin_platform_driver(tegra_core_domain_driver); diff --git a/include/soc/tegra/common.h b/include/soc/tegra/common.h index 57b56793a9e5..6c2ccbbbf073 100644 --- a/include/soc/tegra/common.h +++ b/include/soc/tegra/common.h @@ -27,6 +27,7 @@ struct tegra_core_opp_params {
#ifdef CONFIG_ARCH_TEGRA bool soc_is_tegra(void); +bool tegra_soc_core_domain_state_synced(void); int devm_tegra_core_dev_init_opp_table(struct device *dev, struct tegra_core_opp_params *cfg); #else @@ -35,6 +36,11 @@ static inline bool soc_is_tegra(void) return false; }
+static inline bool tegra_soc_core_domain_state_synced(void) +{ + return false; +} + static inline int devm_tegra_core_dev_init_opp_table(struct device *dev, struct tegra_core_opp_params *cfg)