diff options
author | Peter De Schrijver <pdeschrijver@nvidia.com> | 2012-01-26 16:22:03 (GMT) |
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committer | Olof Johansson <olof@lixom.net> | 2012-02-06 17:16:16 (GMT) |
commit | 22b8b85d902b0ff4dffb281303ea5bb0369c17aa (patch) | |
tree | c5e5ba437c7590f3b0d033ab741277b29408d6be /arch/arm/mach-tegra | |
parent | c76fcc8af16fafc4a349192f8f08a5f7e6d7e706 (diff) | |
download | linux-fsl-qoriq-22b8b85d902b0ff4dffb281303ea5bb0369c17aa.tar.xz |
ARM: tegra: cpuidle driver for tegra
CPUidle driver for tegra. In this version only LP3 (clockgating) is supported.
Based on work by:
Colin Cross <ccross@android.com>
Gary King <gking@nvidia.com>
Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Colin Cross <ccross@android.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'arch/arm/mach-tegra')
-rw-r--r-- | arch/arm/mach-tegra/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/mach-tegra/cpuidle.c | 107 |
2 files changed, 109 insertions, 0 deletions
diff --git a/arch/arm/mach-tegra/Makefile b/arch/arm/mach-tegra/Makefile index b2ac108..0a5bc47 100644 --- a/arch/arm/mach-tegra/Makefile +++ b/arch/arm/mach-tegra/Makefile @@ -7,6 +7,8 @@ obj-y += clock.o obj-y += timer.o obj-y += pinmux.o obj-y += fuse.o +obj-y += cpuidle.o +obj-y += sleep.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += powergate.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra2_clocks.o obj-$(CONFIG_ARCH_TEGRA_2x_SOC) += tegra2_emc.o diff --git a/arch/arm/mach-tegra/cpuidle.c b/arch/arm/mach-tegra/cpuidle.c new file mode 100644 index 0000000..d83a8c0 --- /dev/null +++ b/arch/arm/mach-tegra/cpuidle.c @@ -0,0 +1,107 @@ +/* + * arch/arm/mach-tegra/cpuidle.c + * + * CPU idle driver for Tegra CPUs + * + * Copyright (c) 2010-2012, NVIDIA Corporation. + * Copyright (c) 2011 Google, Inc. + * Author: Colin Cross <ccross@android.com> + * Gary King <gking@nvidia.com> + * + * Rework for 3.3 by Peter De Schrijver <pdeschrijver@nvidia.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/cpu.h> +#include <linux/cpuidle.h> +#include <linux/hrtimer.h> + +#include <mach/iomap.h> + +extern void tegra_cpu_wfi(void); + +static int tegra_idle_enter_lp3(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index); + +struct cpuidle_driver tegra_idle_driver = { + .name = "tegra_idle", + .owner = THIS_MODULE, + .state_count = 1, + .states = { + [0] = { + .enter = tegra_idle_enter_lp3, + .exit_latency = 10, + .target_residency = 10, + .power_usage = 600, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "LP3", + .desc = "CPU flow-controlled", + }, + }, +}; + +static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device); + +static int tegra_idle_enter_lp3(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + ktime_t enter, exit; + s64 us; + + local_irq_disable(); + local_fiq_disable(); + + enter = ktime_get(); + + tegra_cpu_wfi(); + + exit = ktime_sub(ktime_get(), enter); + us = ktime_to_us(exit); + + local_fiq_enable(); + local_irq_enable(); + + dev->last_residency = us; + + return index; +} + +static int __init tegra_cpuidle_init(void) +{ + int ret; + unsigned int cpu; + struct cpuidle_device *dev; + struct cpuidle_driver *drv = &tegra_idle_driver; + + ret = cpuidle_register_driver(&tegra_idle_driver); + if (ret) { + pr_err("CPUidle driver registration failed\n"); + return ret; + } + + for_each_possible_cpu(cpu) { + dev = &per_cpu(tegra_idle_device, cpu); + dev->cpu = cpu; + + dev->state_count = drv->state_count; + ret = cpuidle_register_device(dev); + if (ret) { + pr_err("CPU%u: CPUidle device registration failed\n", + cpu); + return ret; + } + } + return 0; +} +device_initcall(tegra_cpuidle_init); |