From 380d2b2d5a0491e47dfa250b40e3d849a922871d Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Fri, 28 May 2021 02:54:00 +0300 Subject: [PATCH 1/5] regulator: core: Add regulator_sync_voltage_rdev() Some NVIDIA Tegra devices use a CPU soft-reset method for the reboot and in this case we need to restore the coupled voltages to the state that is suitable for hardware during boot. Add new regulator_sync_voltage_rdev() helper which is needed by regulator drivers in order to sync voltage of a coupled regulators. Acked-by: Mark Brown Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding --- drivers/regulator/core.c | 23 +++++++++++++++++++++++ include/linux/regulator/driver.h | 1 + 2 files changed, 24 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index f192bf19492e..ead0b6d2af45 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -4105,6 +4105,29 @@ int regulator_set_voltage_time_sel(struct regulator_dev *rdev, } EXPORT_SYMBOL_GPL(regulator_set_voltage_time_sel); +int regulator_sync_voltage_rdev(struct regulator_dev *rdev) +{ + int ret; + + regulator_lock(rdev); + + if (!rdev->desc->ops->set_voltage && + !rdev->desc->ops->set_voltage_sel) { + ret = -EINVAL; + goto out; + } + + /* balance only, if regulator is coupled */ + if (rdev->coupling_desc.n_coupled > 1) + ret = regulator_balance_voltage(rdev, PM_SUSPEND_ON); + else + ret = -EOPNOTSUPP; + +out: + regulator_unlock(rdev); + return ret; +} + /** * regulator_sync_voltage - re-apply last regulator output voltage * @regulator: regulator source diff --git a/include/linux/regulator/driver.h b/include/linux/regulator/driver.h index 4ea520c248e9..35e5a611db81 100644 --- a/include/linux/regulator/driver.h +++ b/include/linux/regulator/driver.h @@ -540,6 +540,7 @@ int regulator_set_current_limit_regmap(struct regulator_dev *rdev, int regulator_get_current_limit_regmap(struct regulator_dev *rdev); void *regulator_get_init_drvdata(struct regulator_init_data *reg_init_data); int regulator_set_ramp_delay_regmap(struct regulator_dev *rdev, int ramp_delay); +int regulator_sync_voltage_rdev(struct regulator_dev *rdev); /* * Helper functions intended to be used by regulator drivers prior registering From 03978d42ed0d69cb5d38dfb0aeb5216d19507c60 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Fri, 28 May 2021 02:54:01 +0300 Subject: [PATCH 2/5] soc/tegra: regulators: Bump voltages on system reboot MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Ensure that SoC voltages are at a level suitable for a system reboot. This is important for some devices that use CPU reset method for the rebooting. SoC CPU and core voltages now are be restored to a level that is suitable for rebooting. This patch fixes hang on reboot on Asus Transformer TF101, it was also reported as fixing some of reboot issues on Toshiba AC100. Reported-by: Nikola Milosavljević Tested-by: Nikola Milosavljević # TF101 Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding --- drivers/soc/tegra/regulators-tegra20.c | 75 +++++++++++++++++++++++++- drivers/soc/tegra/regulators-tegra30.c | 75 +++++++++++++++++++++++++- 2 files changed, 148 insertions(+), 2 deletions(-) diff --git a/drivers/soc/tegra/regulators-tegra20.c b/drivers/soc/tegra/regulators-tegra20.c index 367a71a3cd10..3479be5ee494 100644 --- a/drivers/soc/tegra/regulators-tegra20.c +++ b/drivers/soc/tegra/regulators-tegra20.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -21,7 +22,10 @@ struct tegra_regulator_coupler { struct regulator_dev *core_rdev; struct regulator_dev *cpu_rdev; struct regulator_dev *rtc_rdev; - int core_min_uV; + struct notifier_block reboot_notifier; + int core_min_uV, cpu_min_uV; + bool sys_reboot_mode_req; + bool sys_reboot_mode; }; static inline struct tegra_regulator_coupler * @@ -242,6 +246,10 @@ static int tegra20_cpu_voltage_update(struct tegra_regulator_coupler *tegra, if (cpu_uV < 0) return cpu_uV; + /* store boot voltage level */ + if (!tegra->cpu_min_uV) + tegra->cpu_min_uV = cpu_uV; + /* * CPU's regulator may not have any consumers, hence the voltage * must not be changed in that case because CPU simply won't @@ -250,6 +258,10 @@ static int tegra20_cpu_voltage_update(struct tegra_regulator_coupler *tegra, if (!cpu_min_uV_consumers) cpu_min_uV = cpu_uV; + /* restore boot voltage level */ + if (tegra->sys_reboot_mode) + cpu_min_uV = max(cpu_min_uV, tegra->cpu_min_uV); + if (cpu_min_uV > cpu_uV) { err = tegra20_core_rtc_update(tegra, core_rdev, rtc_rdev, cpu_uV, cpu_min_uV); @@ -290,6 +302,8 @@ static int tegra20_regulator_balance_voltage(struct regulator_coupler *coupler, return -EINVAL; } + tegra->sys_reboot_mode = READ_ONCE(tegra->sys_reboot_mode_req); + if (rdev == cpu_rdev) return tegra20_cpu_voltage_update(tegra, cpu_rdev, core_rdev, rtc_rdev); @@ -303,6 +317,51 @@ static int tegra20_regulator_balance_voltage(struct regulator_coupler *coupler, return -EPERM; } +static int tegra20_regulator_prepare_reboot(struct tegra_regulator_coupler *tegra, + bool sys_reboot_mode) +{ + int err; + + if (!tegra->core_rdev || !tegra->rtc_rdev || !tegra->cpu_rdev) + return 0; + + WRITE_ONCE(tegra->sys_reboot_mode_req, true); + + /* + * Some devices use CPU soft-reboot method and in this case we + * should ensure that voltages are sane for the reboot by restoring + * the minimum boot levels. + */ + err = regulator_sync_voltage_rdev(tegra->cpu_rdev); + if (err) + return err; + + err = regulator_sync_voltage_rdev(tegra->core_rdev); + if (err) + return err; + + WRITE_ONCE(tegra->sys_reboot_mode_req, sys_reboot_mode); + + return 0; +} + +static int tegra20_regulator_reboot(struct notifier_block *notifier, + unsigned long event, void *cmd) +{ + struct tegra_regulator_coupler *tegra; + int ret; + + if (event != SYS_RESTART) + return NOTIFY_DONE; + + tegra = container_of(notifier, struct tegra_regulator_coupler, + reboot_notifier); + + ret = tegra20_regulator_prepare_reboot(tegra, true); + + return notifier_from_errno(ret); +} + static int tegra20_regulator_attach(struct regulator_coupler *coupler, struct regulator_dev *rdev) { @@ -335,6 +394,14 @@ static int tegra20_regulator_detach(struct regulator_coupler *coupler, { struct tegra_regulator_coupler *tegra = to_tegra_coupler(coupler); + /* + * We don't expect regulators to be decoupled during reboot, + * this may race with the reboot handler and shouldn't ever + * happen in practice. + */ + if (WARN_ON_ONCE(system_state > SYSTEM_RUNNING)) + return -EPERM; + if (tegra->core_rdev == rdev) { tegra->core_rdev = NULL; return 0; @@ -359,13 +426,19 @@ static struct tegra_regulator_coupler tegra20_coupler = { .detach_regulator = tegra20_regulator_detach, .balance_voltage = tegra20_regulator_balance_voltage, }, + .reboot_notifier.notifier_call = tegra20_regulator_reboot, }; static int __init tegra_regulator_coupler_init(void) { + int err; + if (!of_machine_is_compatible("nvidia,tegra20")) return 0; + err = register_reboot_notifier(&tegra20_coupler.reboot_notifier); + WARN_ON(err); + return regulator_coupler_register(&tegra20_coupler.coupler); } arch_initcall(tegra_regulator_coupler_init); diff --git a/drivers/soc/tegra/regulators-tegra30.c b/drivers/soc/tegra/regulators-tegra30.c index 0e776b20f625..18fe53d0a870 100644 --- a/drivers/soc/tegra/regulators-tegra30.c +++ b/drivers/soc/tegra/regulators-tegra30.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -22,7 +23,10 @@ struct tegra_regulator_coupler { struct regulator_coupler coupler; struct regulator_dev *core_rdev; struct regulator_dev *cpu_rdev; - int core_min_uV; + struct notifier_block reboot_notifier; + int core_min_uV, cpu_min_uV; + bool sys_reboot_mode_req; + bool sys_reboot_mode; }; static inline struct tegra_regulator_coupler * @@ -172,6 +176,10 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra, if (cpu_uV < 0) return cpu_uV; + /* store boot voltage level */ + if (!tegra->cpu_min_uV) + tegra->cpu_min_uV = cpu_uV; + /* * CPU's regulator may not have any consumers, hence the voltage * must not be changed in that case because CPU simply won't @@ -195,6 +203,10 @@ static int tegra30_voltage_update(struct tegra_regulator_coupler *tegra, if (err) return err; + /* restore boot voltage level */ + if (tegra->sys_reboot_mode) + cpu_min_uV = max(cpu_min_uV, tegra->cpu_min_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); @@ -263,9 +275,56 @@ static int tegra30_regulator_balance_voltage(struct regulator_coupler *coupler, return -EINVAL; } + tegra->sys_reboot_mode = READ_ONCE(tegra->sys_reboot_mode_req); + return tegra30_voltage_update(tegra, cpu_rdev, core_rdev); } +static int tegra30_regulator_prepare_reboot(struct tegra_regulator_coupler *tegra, + bool sys_reboot_mode) +{ + int err; + + if (!tegra->core_rdev || !tegra->cpu_rdev) + return 0; + + WRITE_ONCE(tegra->sys_reboot_mode_req, true); + + /* + * Some devices use CPU soft-reboot method and in this case we + * should ensure that voltages are sane for the reboot by restoring + * the minimum boot levels. + */ + err = regulator_sync_voltage_rdev(tegra->cpu_rdev); + if (err) + return err; + + err = regulator_sync_voltage_rdev(tegra->core_rdev); + if (err) + return err; + + WRITE_ONCE(tegra->sys_reboot_mode_req, sys_reboot_mode); + + return 0; +} + +static int tegra30_regulator_reboot(struct notifier_block *notifier, + unsigned long event, void *cmd) +{ + struct tegra_regulator_coupler *tegra; + int ret; + + if (event != SYS_RESTART) + return NOTIFY_DONE; + + tegra = container_of(notifier, struct tegra_regulator_coupler, + reboot_notifier); + + ret = tegra30_regulator_prepare_reboot(tegra, true); + + return notifier_from_errno(ret); +} + static int tegra30_regulator_attach(struct regulator_coupler *coupler, struct regulator_dev *rdev) { @@ -292,6 +351,14 @@ static int tegra30_regulator_detach(struct regulator_coupler *coupler, { struct tegra_regulator_coupler *tegra = to_tegra_coupler(coupler); + /* + * We don't expect regulators to be decoupled during reboot, + * this may race with the reboot handler and shouldn't ever + * happen in practice. + */ + if (WARN_ON_ONCE(system_state > SYSTEM_RUNNING)) + return -EPERM; + if (tegra->core_rdev == rdev) { tegra->core_rdev = NULL; return 0; @@ -311,13 +378,19 @@ static struct tegra_regulator_coupler tegra30_coupler = { .detach_regulator = tegra30_regulator_detach, .balance_voltage = tegra30_regulator_balance_voltage, }, + .reboot_notifier.notifier_call = tegra30_regulator_reboot, }; static int __init tegra_regulator_coupler_init(void) { + int err; + if (!of_machine_is_compatible("nvidia,tegra30")) return 0; + err = register_reboot_notifier(&tegra30_coupler.reboot_notifier); + WARN_ON(err); + return regulator_coupler_register(&tegra30_coupler.coupler); } arch_initcall(tegra_regulator_coupler_init); From 4333e0300023c701d4c7bf0b834179ca19d4ddf8 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Fri, 28 May 2021 02:54:02 +0300 Subject: [PATCH 3/5] soc/tegra: Add stub for soc_is_tegra() Add stub required for compile-testing of drivers. Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding --- include/soc/tegra/common.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/soc/tegra/common.h b/include/soc/tegra/common.h index 98027a76ce3d..744280ecab5f 100644 --- a/include/soc/tegra/common.h +++ b/include/soc/tegra/common.h @@ -6,6 +6,15 @@ #ifndef __SOC_TEGRA_COMMON_H__ #define __SOC_TEGRA_COMMON_H__ +#include + +#ifdef CONFIG_ARCH_TEGRA bool soc_is_tegra(void); +#else +static inline bool soc_is_tegra(void) +{ + return false; +} +#endif #endif /* __SOC_TEGRA_COMMON_H__ */ From b8818de9c0c107019c2a90a50423c1b929176f3c Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Fri, 28 May 2021 02:54:03 +0300 Subject: [PATCH 4/5] soc/tegra: Add devm_tegra_core_dev_init_opp_table() Add common helper which initializes OPP table for Tegra SoC core devices. Tested-by: Peter Geis # Ouya T30 Tested-by: Paul Fertser # PAZ00 T20 Tested-by: Nicolas Chauvet # PAZ00 T20 and TK1 T124 Tested-by: Matt Merhar # Ouya T30 Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding --- drivers/soc/tegra/common.c | 97 ++++++++++++++++++++++++++++++++++++++ include/soc/tegra/common.h | 22 +++++++++ 2 files changed, 119 insertions(+) diff --git a/drivers/soc/tegra/common.c b/drivers/soc/tegra/common.c index 3dc54f59cafe..cd33e99249c3 100644 --- a/drivers/soc/tegra/common.c +++ b/drivers/soc/tegra/common.c @@ -3,9 +3,16 @@ * Copyright (C) 2014 NVIDIA CORPORATION. All rights reserved. */ +#define dev_fmt(fmt) "tegra-soc: " fmt + +#include +#include +#include #include +#include #include +#include static const struct of_device_id tegra_machine_match[] = { { .compatible = "nvidia,tegra20", }, @@ -31,3 +38,93 @@ bool soc_is_tegra(void) return match != NULL; } + +static int tegra_core_dev_init_opp_state(struct device *dev) +{ + unsigned long rate; + struct clk *clk; + int err; + + clk = devm_clk_get(dev, NULL); + if (IS_ERR(clk)) { + dev_err(dev, "failed to get clk: %pe\n", clk); + return PTR_ERR(clk); + } + + rate = clk_get_rate(clk); + if (!rate) { + dev_err(dev, "failed to get clk rate\n"); + return -EINVAL; + } + + /* first dummy rate-setting initializes voltage vote */ + err = dev_pm_opp_set_rate(dev, rate); + if (err) { + dev_err(dev, "failed to initialize OPP clock: %d\n", err); + return err; + } + + return 0; +} + +/** + * devm_tegra_core_dev_init_opp_table() - initialize OPP table + * @dev: device for which OPP table is initialized + * @params: pointer to the OPP table configuration + * + * This function will initialize OPP table and sync OPP state of a Tegra SoC + * core device. + * + * Return: 0 on success or errorno. + */ +int devm_tegra_core_dev_init_opp_table(struct device *dev, + struct tegra_core_opp_params *params) +{ + u32 hw_version; + int err; + + err = devm_pm_opp_set_clkname(dev, NULL); + if (err) { + dev_err(dev, "failed to set OPP clk: %d\n", err); + return err; + } + + /* Tegra114+ doesn't support OPP yet */ + if (!of_machine_is_compatible("nvidia,tegra20") && + !of_machine_is_compatible("nvidia,tegra30")) + return -ENODEV; + + if (of_machine_is_compatible("nvidia,tegra20")) + hw_version = BIT(tegra_sku_info.soc_process_id); + else + hw_version = BIT(tegra_sku_info.soc_speedo_id); + + err = devm_pm_opp_set_supported_hw(dev, &hw_version, 1); + if (err) { + dev_err(dev, "failed to set OPP supported HW: %d\n", err); + return err; + } + + /* + * Older device-trees have an empty OPP table, we will get + * -ENODEV from devm_pm_opp_of_add_table() in this case. + */ + err = devm_pm_opp_of_add_table(dev); + if (err) { + if (err == -ENODEV) + dev_err_once(dev, "OPP table not found, please update device-tree\n"); + else + dev_err(dev, "failed to add OPP table: %d\n", err); + + return err; + } + + if (params->init_state) { + err = tegra_core_dev_init_opp_state(dev); + if (err) + return err; + } + + return 0; +} +EXPORT_SYMBOL_GPL(devm_tegra_core_dev_init_opp_table); diff --git a/include/soc/tegra/common.h b/include/soc/tegra/common.h index 744280ecab5f..af41ad80ec21 100644 --- a/include/soc/tegra/common.h +++ b/include/soc/tegra/common.h @@ -6,15 +6,37 @@ #ifndef __SOC_TEGRA_COMMON_H__ #define __SOC_TEGRA_COMMON_H__ +#include #include +struct device; + +/** + * Tegra SoC core device OPP table configuration + * + * @init_state: pre-initialize OPP state of a device + */ +struct tegra_core_opp_params { + bool init_state; +}; + #ifdef CONFIG_ARCH_TEGRA bool soc_is_tegra(void); + +int devm_tegra_core_dev_init_opp_table(struct device *dev, + struct tegra_core_opp_params *params); #else static inline bool soc_is_tegra(void) { return false; } + +static inline int +devm_tegra_core_dev_init_opp_table(struct device *dev, + struct tegra_core_opp_params *params) +{ + return -ENODEV; +} #endif #endif /* __SOC_TEGRA_COMMON_H__ */ From 30b44e81772a5caa983000057ce1cd9cb4531647 Mon Sep 17 00:00:00 2001 From: Dmitry Osipenko Date: Fri, 28 May 2021 02:54:04 +0300 Subject: [PATCH 5/5] soc/tegra: fuse: Add stubs needed for compile-testing Add missing stubs that will allow Tegra memory driver to be compile-tested by kernel build bots. Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding --- include/soc/tegra/fuse.h | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/include/soc/tegra/fuse.h b/include/soc/tegra/fuse.h index 78cbc787a4dc..990701f788bc 100644 --- a/include/soc/tegra/fuse.h +++ b/include/soc/tegra/fuse.h @@ -52,14 +52,28 @@ struct tegra_sku_info { enum tegra_revision revision; }; +#ifdef CONFIG_ARCH_TEGRA +extern struct tegra_sku_info tegra_sku_info; u32 tegra_read_straps(void); u32 tegra_read_ram_code(void); int tegra_fuse_readl(unsigned long offset, u32 *value); - -#ifdef CONFIG_ARCH_TEGRA -extern struct tegra_sku_info tegra_sku_info; #else static struct tegra_sku_info tegra_sku_info __maybe_unused; + +static inline u32 tegra_read_straps(void) +{ + return 0; +} + +static inline u32 tegra_read_ram_code(void) +{ + return 0; +} + +static inline int tegra_fuse_readl(unsigned long offset, u32 *value) +{ + return -ENODEV; +} #endif struct device *tegra_soc_device_register(void);