The driver's code is refactored in a way that will make it easy to support Tegra30/114/124 SoCs by this unified driver later on. The current functionality is equal to the old Tegra20 driver, only the code's structure changed a tad. This is also a proper platform driver now. Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> --- arch/arm/mach-tegra/Makefile | 3 - arch/arm/mach-tegra/cpuidle-tegra20.c | 215 -------------------- arch/arm/mach-tegra/cpuidle.c | 14 +- arch/arm/mach-tegra/cpuidle.h | 4 - drivers/cpuidle/Kconfig.arm | 8 + drivers/cpuidle/Makefile | 1 + drivers/cpuidle/cpuidle-tegra.c | 269 ++++++++++++++++++++++++++ include/soc/tegra/cpuidle.h | 2 +- 8 files changed, 281 insertions(+), 235 deletions(-) delete mode 100644 arch/arm/mach-tegra/cpuidle-tegra20.c create mode 100644 drivers/cpuidle/cpuidle-tegra.c diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index 965862608ff6..8425bb5608d5 100644 --- a/arch/arm/mach-tegra/Makefile +++ b/arch/arm/mach-tegra/Makefile @@ -12,9 +12,6 @@ obj-y += sleep-tegra20.o obj-y += sleep-tegra30.o obj-$(CONFIG_CPU_IDLE) += cpuidle.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += pm-tegra20.o -ifeq ($(CONFIG_CPU_IDLE),y) -obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += cpuidle-tegra20.o -endif obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += pm-tegra30.o ifeq ($(CONFIG_CPU_IDLE),y) obj-$(CONFIG_ARCH_TEGRA_3x_SOC) += cpuidle-tegra30.o diff --git a/arch/arm/mach-tegra/cpuidle-tegra20.c b/arch/arm/mach-tegra/cpuidle-tegra20.c deleted file mode 100644 index 78cc424fac35..000000000000 --- a/arch/arm/mach-tegra/cpuidle-tegra20.c +++ /dev/null @@ -1,215 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * CPU idle driver for Tegra CPUs - * - * Copyright (c) 2010-2012, NVIDIA Corporation. - * Copyright (c) 2011 Google, Inc. - * Author: Colin Cross <ccross@xxxxxxxxxxx> - * Gary King <gking@xxxxxxxxxx> - * - * Rework for 3.3 by Peter De Schrijver <pdeschrijver@xxxxxxxxxx> - */ - -#include <linux/clk/tegra.h> -#include <linux/tick.h> -#include <linux/cpuidle.h> -#include <linux/cpu_pm.h> -#include <linux/kernel.h> -#include <linux/ktime.h> -#include <linux/module.h> - -#include <soc/tegra/flowctrl.h> -#include <soc/tegra/pm.h> - -#include <asm/cpuidle.h> -#include <asm/smp_plat.h> -#include <asm/suspend.h> - -#include "cpuidle.h" -#include "iomap.h" -#include "irq.h" -#include "reset.h" -#include "sleep.h" - -#ifdef CONFIG_PM_SLEEP -static atomic_t abort_flag; -static atomic_t abort_barrier; -static int tegra20_idle_lp2_coupled(struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index); -#define TEGRA20_MAX_STATES 2 -#else -#define TEGRA20_MAX_STATES 1 -#endif - -static struct cpuidle_driver tegra_idle_driver = { - .name = "tegra_idle", - .owner = THIS_MODULE, - .states = { - ARM_CPUIDLE_WFI_STATE_PWR(600), -#ifdef CONFIG_PM_SLEEP - { - .enter = tegra20_idle_lp2_coupled, - .exit_latency = 5000, - .target_residency = 10000, - .power_usage = 0, - .flags = CPUIDLE_FLAG_COUPLED | - CPUIDLE_FLAG_TIMER_STOP, - .name = "powered-down", - .desc = "CPU power gated", - }, -#endif - }, - .state_count = TEGRA20_MAX_STATES, - .safe_state_index = 0, -}; - -#ifdef CONFIG_PM_SLEEP -#ifdef CONFIG_SMP -static void tegra20_wake_cpu1_from_reset(void) -{ - /* enable cpu clock on cpu */ - tegra_enable_cpu_clock(1); - - /* take the CPU out of reset */ - tegra_cpu_out_of_reset(1); - - /* unhalt the cpu */ - flowctrl_write_cpu_halt(1, 0); -} -#else -static inline void tegra20_wake_cpu1_from_reset(void) -{ -} -#endif - -static void tegra20_report_cpus_state(void) -{ - unsigned int cpu, lcpu; - - pr_err("secondary CPU taking too long to park\n"); - - for_each_cpu(lcpu, cpu_possible_mask) { - cpu = cpu_logical_map(lcpu); - - pr_err("cpu%u: online=%d flowctrl_csr=0x%08x\n", - cpu, cpu_online(lcpu), flowctrl_read_cpu_csr(cpu)); - } -} - -static int tegra20_wait_for_secondary_cpu_parking(void) -{ - unsigned int retries = 3; - - while (retries--) { - ktime_t timeout = ktime_add_ms(ktime_get(), 500); - - /* - * The primary CPU0 core shall wait for the secondaries - * shutdown in order to power-off CPU's cluster safely. - * The timeout value depends on the current CPU frequency, - * it takes about 40-150us in average and over 1000us in - * a worst case scenario. - */ - do { - if (tegra_cpu_rail_off_ready()) - return 0; - - } while (ktime_before(ktime_get(), timeout)); - - tegra20_report_cpus_state(); - } - - pr_err("timed out waiting secondaries to park\n"); - - return -ETIMEDOUT; -} - -static bool tegra20_cpu_cluster_power_down(struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index) -{ - bool ret; - - if (tegra20_wait_for_secondary_cpu_parking()) - return false; - - ret = !tegra_pm_enter_lp2(); - - if (cpu_online(1)) - tegra20_wake_cpu1_from_reset(); - - return ret; -} - -#ifdef CONFIG_SMP -static bool tegra20_idle_enter_lp2_cpu_1(struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index) -{ - cpu_suspend(dev->cpu, tegra_pm_park_secondary_cpu); - - return true; -} -#else -static inline bool tegra20_idle_enter_lp2_cpu_1(struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index) -{ - return true; -} -#endif - -static int tegra20_idle_lp2_coupled(struct cpuidle_device *dev, - struct cpuidle_driver *drv, - int index) -{ - bool entered_lp2 = false; - - if (tegra_pending_sgi()) - atomic_set(&abort_flag, 1); - - cpuidle_coupled_parallel_barrier(dev, &abort_barrier); - - if (atomic_read(&abort_flag)) { - cpuidle_coupled_parallel_barrier(dev, &abort_barrier); - /* clean flag for next coming */ - atomic_set(&abort_flag, 0); - return -EINTR; - } - - local_fiq_disable(); - - tegra_pm_set_cpu_in_lp2(); - cpu_pm_enter(); - - if (dev->cpu == 0) - entered_lp2 = tegra20_cpu_cluster_power_down(dev, drv, index); - else - entered_lp2 = tegra20_idle_enter_lp2_cpu_1(dev, drv, index); - - cpu_pm_exit(); - tegra_pm_clear_cpu_in_lp2(); - - local_fiq_enable(); - - return entered_lp2 ? index : 0; -} -#endif - -/* - * Tegra20 HW appears to have a bug such that PCIe device interrupts, whether - * they are legacy IRQs or MSI, are lost when LP2 is enabled. To work around - * this, simply disable LP2 if the PCI driver and DT node are both enabled. - */ -void tegra20_cpuidle_pcie_irqs_in_use(void) -{ - pr_info_once( - "Disabling cpuidle LP2 state, since PCIe IRQs are in use\n"); - cpuidle_driver_state_disabled(&tegra_idle_driver, 1, true); -} - -int __init tegra20_cpuidle_init(void) -{ - return cpuidle_register(&tegra_idle_driver, cpu_possible_mask); -} diff --git a/arch/arm/mach-tegra/cpuidle.c b/arch/arm/mach-tegra/cpuidle.c index d565c44cfc93..eee85d517783 100644 --- a/arch/arm/mach-tegra/cpuidle.c +++ b/arch/arm/mach-tegra/cpuidle.c @@ -14,6 +14,7 @@ #include <linux/kernel.h> #include <linux/module.h> +#include <linux/platform_device.h> #include <soc/tegra/fuse.h> @@ -23,8 +24,7 @@ void __init tegra_cpuidle_init(void) { switch (tegra_get_chip_id()) { case TEGRA20: - if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC)) - tegra20_cpuidle_init(); + platform_device_register_simple("tegra-cpuidle", -1, NULL, 0); break; case TEGRA30: if (IS_ENABLED(CONFIG_ARCH_TEGRA_3x_SOC)) @@ -38,13 +38,3 @@ void __init tegra_cpuidle_init(void) break; } } - -void tegra_cpuidle_pcie_irqs_in_use(void) -{ - switch (tegra_get_chip_id()) { - case TEGRA20: - if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC)) - tegra20_cpuidle_pcie_irqs_in_use(); - break; - } -} diff --git a/arch/arm/mach-tegra/cpuidle.h b/arch/arm/mach-tegra/cpuidle.h index 4e1f459f5bd8..eeb37baf18e1 100644 --- a/arch/arm/mach-tegra/cpuidle.h +++ b/arch/arm/mach-tegra/cpuidle.h @@ -7,15 +7,11 @@ #define __MACH_TEGRA_CPUIDLE_H #ifdef CONFIG_CPU_IDLE -int tegra20_cpuidle_init(void); -void tegra20_cpuidle_pcie_irqs_in_use(void); int tegra30_cpuidle_init(void); int tegra114_cpuidle_init(void); void tegra_cpuidle_init(void); -void tegra_cpuidle_pcie_irqs_in_use(void); #else static inline void tegra_cpuidle_init(void) {} -static inline void tegra_cpuidle_pcie_irqs_in_use(void) {} #endif #endif diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm index d8530475493c..6952bf7bb260 100644 --- a/drivers/cpuidle/Kconfig.arm +++ b/drivers/cpuidle/Kconfig.arm @@ -86,3 +86,11 @@ config ARM_MVEBU_V7_CPUIDLE depends on ARCH_MVEBU && !ARM64 help Select this to enable cpuidle on Armada 370, 38x and XP processors. + +config ARM_TEGRA_CPUIDLE + bool "CPU Idle Driver for NVIDIA Tegra SoCs" + depends on ARCH_TEGRA && !ARM64 + select ARCH_NEEDS_CPU_IDLE_COUPLED if SMP + select ARM_CPU_SUSPEND + help + Select this to enable cpuidle for NVIDIA Tegra20/30/114/124 SoCs. diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index ee70d5cc5b99..a15e4808d295 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o obj-$(CONFIG_ARM_CPUIDLE) += cpuidle-arm.o obj-$(CONFIG_ARM_PSCI_CPUIDLE) += cpuidle-psci.o +obj-$(CONFIG_ARM_TEGRA_CPUIDLE) += cpuidle-tegra.o ############################################################################### # MIPS drivers diff --git a/drivers/cpuidle/cpuidle-tegra.c b/drivers/cpuidle/cpuidle-tegra.c new file mode 100644 index 000000000000..6f7955b9d4bd --- /dev/null +++ b/drivers/cpuidle/cpuidle-tegra.c @@ -0,0 +1,269 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * CPU idle driver for Tegra CPUs + * + * Copyright (c) 2010-2013, NVIDIA Corporation. + * Copyright (c) 2011 Google, Inc. + * Author: Colin Cross <ccross@xxxxxxxxxxx> + * Gary King <gking@xxxxxxxxxx> + * + * Rework for 3.3 by Peter De Schrijver <pdeschrijver@xxxxxxxxxx> + * + * Tegra20/124 driver unification by Dmitry Osipenko <digetx@xxxxxxxxx> + */ + +#define pr_fmt(fmt) "tegra-cpuidle: " fmt + +#include <linux/atomic.h> +#include <linux/cpuidle.h> +#include <linux/cpumask.h> +#include <linux/cpu_pm.h> +#include <linux/errno.h> +#include <linux/ktime.h> +#include <linux/platform_device.h> +#include <linux/types.h> + +#include <linux/clk/tegra.h> + +#include <soc/tegra/cpuidle.h> +#include <soc/tegra/flowctrl.h> +#include <soc/tegra/fuse.h> +#include <soc/tegra/irq.h> +#include <soc/tegra/pm.h> + +#include <asm/cpuidle.h> +#include <asm/smp_plat.h> +#include <asm/suspend.h> + +enum { + TEGRA_C1, + TEGRA_CC6, + TEGRA_STATE_COUNT, +}; + +static atomic_t tegra_idle_barrier; +static atomic_t tegra_abort_flag; + +static void tegra_cpuidle_report_cpus_state(void) +{ + unsigned int cpu, lcpu; + + pr_err("secondary CPU taking too long to park\n"); + + for_each_cpu(lcpu, cpu_possible_mask) { + cpu = cpu_logical_map(lcpu); + + pr_err("cpu%u: online=%d flowctrl_csr=0x%08x\n", + cpu, cpu_online(lcpu), flowctrl_read_cpu_csr(cpu)); + } +} + +static int tegra_cpuidle_wait_for_secondary_cpus_parking(void) +{ + unsigned int retries = 3; + + while (retries--) { + ktime_t timeout = ktime_add_ms(ktime_get(), 500); + + /* + * The primary CPU0 core shall wait for the secondaries + * shutdown in order to power-off CPU's cluster safely. + * The timeout value depends on the current CPU frequency, + * it takes about 40-150us in average and over 1000us in + * a worst case scenario. + */ + do { + if (tegra_cpu_rail_off_ready()) + return 0; + + } while (ktime_before(ktime_get(), timeout)); + + tegra_cpuidle_report_cpus_state(); + } + + pr_err("timed out waiting secondaries to park\n"); + + return -ETIMEDOUT; +} + +static void tegra_cpuidle_unpark_secondary_cpus(void) +{ + unsigned int cpu, lcpu; + + for_each_cpu(lcpu, cpu_online_mask) { + cpu = cpu_logical_map(lcpu); + + if (cpu > 0) { + tegra_enable_cpu_clock(cpu); + tegra_cpu_out_of_reset(cpu); + flowctrl_write_cpu_halt(cpu, 0); + } + } +} + +static int tegra_cpuidle_cc6_enter(unsigned int cpu) +{ + int ret; + + if (cpu > 0) { + ret = cpu_suspend(cpu, tegra_pm_park_secondary_cpu); + } else { + ret = tegra_cpuidle_wait_for_secondary_cpus_parking(); + if (!ret) + ret = tegra_pm_enter_lp2(); + + tegra_cpuidle_unpark_secondary_cpus(); + } + + return ret; +} + +static int tegra_cpuidle_coupled_barrier(struct cpuidle_device *dev) +{ + if (tegra_pending_sgi()) { + /* + * CPU got local interrupt that will be lost after GIC's + * shutdown because GIC driver doesn't save/restore the + * pending SGI state across CPU cluster PM. Abort and retry + * next time. + */ + atomic_set(&tegra_abort_flag, 1); + } + + cpuidle_coupled_parallel_barrier(dev, &tegra_idle_barrier); + + if (atomic_read(&tegra_abort_flag)) { + cpuidle_coupled_parallel_barrier(dev, &tegra_idle_barrier); + atomic_set(&tegra_abort_flag, 0); + return -EINTR; + } + + return 0; +} + +static int tegra_cpuidle_state_enter(struct cpuidle_device *dev, + int index, unsigned int cpu) +{ + int ret; + + /* + * CC6 state is the "CPU cluster power-off" state. In order to + * enter this state, at first the secondary CPU cores need to be + * parked into offline mode, then the last CPU should clean out + * remaining dirty cache lines into DRAM and trigger Flow Controller + * logic that turns off the cluster's power domain (which includes + * CPU cores, GIC and L2 cache). + */ + if (index == TEGRA_CC6) { + ret = tegra_cpuidle_coupled_barrier(dev); + if (ret) + return ret; + } + + local_fiq_disable(); + tegra_pm_set_cpu_in_lp2(); + cpu_pm_enter(); + + switch (index) { + case TEGRA_CC6: + ret = tegra_cpuidle_cc6_enter(cpu); + break; + default: + ret = -EINVAL; + break; + } + + cpu_pm_exit(); + tegra_pm_clear_cpu_in_lp2(); + local_fiq_enable(); + + return ret; +} + +static int tegra_cpuidle_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + unsigned int cpu = cpu_logical_map(dev->cpu); + int err; + + err = tegra_cpuidle_state_enter(dev, index, cpu); + if (err && err != -EINTR) + pr_err_once("cpu%u failed to enter idle state %d err: %d\n", + cpu, index, err); + + return err ? -1 : index; +} + +/* + * The previous versions of Tegra CPUIDLE driver used a different "legacy" + * terminology for naming of the idling states, while this driver uses the + * new terminology. + * + * Mapping of the old terms into the new ones: + * + * Old | New + * --------- + * LP3 | C1 (CPU core clock gating) + * LP2 | C7 (CPU core power gating) + * LP2 | CC6 (CPU cluster power gating) + * + * Note that that the older CPUIDLE driver versions didn't explicitly + * differentiate the LP2 states because these states either used the same + * code path or because CC6 wasn't supported. + */ +static struct cpuidle_driver tegra_idle_driver = { + .name = "tegra_idle", + .states = { + [TEGRA_C1] = ARM_CPUIDLE_WFI_STATE_PWR(600), + [TEGRA_CC6] = { + .enter = tegra_cpuidle_enter, + .exit_latency = 5000, + .target_residency = 10000, + .power_usage = 0, + .flags = CPUIDLE_FLAG_TIMER_STOP | + CPUIDLE_FLAG_COUPLED, + .name = "CC6", + .desc = "CPU cluster powered off", + }, + }, + .state_count = TEGRA_STATE_COUNT, + .safe_state_index = TEGRA_C1, +}; + +/* + * Tegra20 HW appears to have a bug such that PCIe device interrupts, whether + * they are legacy IRQs or MSI, are lost when CC6 is enabled. To work around + * this, simply disable CC6 if the PCI driver and DT node are both enabled. + */ +void tegra_cpuidle_pcie_irqs_in_use(void) +{ + if (tegra_idle_driver.states[TEGRA_CC6].disabled || + tegra_get_chip_id() != TEGRA20) + return; + + pr_info("disabling CC6 state, since PCIe IRQs are in use\n"); + cpuidle_driver_state_disabled(&tegra_idle_driver, TEGRA_CC6, true); + tegra_idle_driver.states[TEGRA_CC6].disabled = true; +} + +static int tegra_cpuidle_probe(struct platform_device *pdev) +{ + /* + * Required suspend-resume functionality, which is provided by the + * Tegra-arch core and PMC driver, is unavailable if PM-sleep option + * is disabled. + */ + if (!IS_ENABLED(CONFIG_PM_SLEEP)) + tegra_idle_driver.states[TEGRA_CC6].disabled = true; + + return cpuidle_register(&tegra_idle_driver, cpu_possible_mask); +} + +static struct platform_driver tegra_cpuidle_driver = { + .probe = tegra_cpuidle_probe, + .driver = { + .name = "tegra-cpuidle", + }, +}; +builtin_platform_driver(tegra_cpuidle_driver); diff --git a/include/soc/tegra/cpuidle.h b/include/soc/tegra/cpuidle.h index 029ba1f4b2cc..5665975015d8 100644 --- a/include/soc/tegra/cpuidle.h +++ b/include/soc/tegra/cpuidle.h @@ -6,7 +6,7 @@ #ifndef __SOC_TEGRA_CPUIDLE_H__ #define __SOC_TEGRA_CPUIDLE_H__ -#if defined(CONFIG_ARM) && defined(CONFIG_ARCH_TEGRA) && defined(CONFIG_CPU_IDLE) +#ifdef CONFIG_ARM_TEGRA_CPUIDLE void tegra_cpuidle_pcie_irqs_in_use(void); #else static inline void tegra_cpuidle_pcie_irqs_in_use(void) -- 2.24.0