Merge tag 'highbank-cpuidle' of git://sources.calxeda.com/kernel/linux into next/soc (c3e5dba4) · Commits · e / devices / android_kernel_teracube_emerald

drivers/cpuidle/Kconfig

+10 −0

Original line number	Diff line number	Diff line
		@@ -21,3 +21,13 @@ config CPU_IDLE_GOV_MENU

		config ARCH_NEEDS_CPU_IDLE_COUPLED
		def_bool n

		if CPU_IDLE

		config CPU_IDLE_CALXEDA
		bool "CPU Idle Driver for Calxeda processors"
		depends on ARCH_HIGHBANK
		help
		Select this to enable cpuidle on Calxeda processors.

		endif

drivers/cpuidle/Makefile

+2 −0

Original line number	Diff line number	Diff line
		@@ -4,3 +4,5 @@

		obj-y += cpuidle.o driver.o governor.o sysfs.o governors/
		obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o

		obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o

drivers/cpuidle/cpuidle-calxeda.c

0 → 100644

+161 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright 2012 Calxeda, Inc.
		*
		* Based on arch/arm/plat-mxc/cpuidle.c:
		* Copyright 2012 Freescale Semiconductor, Inc.
		* Copyright 2012 Linaro Ltd.
		*
		* This program is free software; you can redistribute it and/or modify it
		* under the terms and conditions of the GNU General Public License,
		* version 2, as published by the Free Software Foundation.
		*
		* This program is distributed in the hope 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.
		*
		* You should have received a copy of the GNU General Public License along with
		* this program. If not, see <http://www.gnu.org/licenses/>.
		*/

		#include <linux/cpuidle.h>
		#include <linux/init.h>
		#include <linux/io.h>
		#include <linux/of.h>
		#include <linux/time.h>
		#include <linux/delay.h>
		#include <linux/suspend.h>
		#include <asm/cpuidle.h>
		#include <asm/proc-fns.h>
		#include <asm/smp_scu.h>
		#include <asm/suspend.h>
		#include <asm/cacheflush.h>
		#include <asm/cp15.h>

		extern void highbank_set_cpu_jump(int cpu, void *jump_addr);
		extern void *scu_base_addr;

		static struct cpuidle_device __percpu *calxeda_idle_cpuidle_devices;

		static inline unsigned int get_auxcr(void)
		{
		unsigned int val;
		asm("mrc p15, 0, %0, c1, c0, 1 @ get AUXCR" : "=r" (val) : : "cc");
		return val;
		}

		static inline void set_auxcr(unsigned int val)
		{
		asm volatile("mcr p15, 0, %0, c1, c0, 1 @ set AUXCR"
		: : "r" (val) : "cc");
		isb();
		}

		static noinline void calxeda_idle_restore(void)
		{
		set_cr(get_cr() \| CR_C);
		set_auxcr(get_auxcr() \| 0x40);
		scu_power_mode(scu_base_addr, SCU_PM_NORMAL);
		}

		static int calxeda_idle_finish(unsigned long val)
		{
		/* Already flushed cache, but do it again as the outer cache functions
		* dirty the cache with spinlocks */
		flush_cache_all();

		set_auxcr(get_auxcr() & ~0x40);
		set_cr(get_cr() & ~CR_C);

		scu_power_mode(scu_base_addr, SCU_PM_DORMANT);

		cpu_do_idle();

		/* Restore things if we didn't enter power-gating */
		calxeda_idle_restore();
		return 1;
		}

		static int calxeda_pwrdown_idle(struct cpuidle_device *dev,
		struct cpuidle_driver *drv,
		int index)
		{
		highbank_set_cpu_jump(smp_processor_id(), cpu_resume);
		cpu_suspend(0, calxeda_idle_finish);
		return index;
		}

		static void calxeda_idle_cpuidle_devices_uninit(void)
		{
		int i;
		struct cpuidle_device *dev;

		for_each_possible_cpu(i) {
		dev = per_cpu_ptr(calxeda_idle_cpuidle_devices, i);
		cpuidle_unregister_device(dev);
		}

		free_percpu(calxeda_idle_cpuidle_devices);
		}

		static struct cpuidle_driver calxeda_idle_driver = {
		.name = "calxeda_idle",
		.en_core_tk_irqen = 1,
		.states = {
		ARM_CPUIDLE_WFI_STATE,
		{
		.name = "PG",
		.desc = "Power Gate",
		.flags = CPUIDLE_FLAG_TIME_VALID,
		.exit_latency = 30,
		.power_usage = 50,
		.target_residency = 200,
		.enter = calxeda_pwrdown_idle,
		},
		},
		.state_count = 2,
		};

		static int __init calxeda_cpuidle_init(void)
		{
		int cpu_id;
		int ret;
		struct cpuidle_device *dev;
		struct cpuidle_driver *drv = &calxeda_idle_driver;

		if (!of_machine_is_compatible("calxeda,highbank"))
		return -ENODEV;

		ret = cpuidle_register_driver(drv);
		if (ret)
		return ret;

		calxeda_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device);
		if (calxeda_idle_cpuidle_devices == NULL) {
		ret = -ENOMEM;
		goto unregister_drv;
		}

		/* initialize state data for each cpuidle_device */
		for_each_possible_cpu(cpu_id) {
		dev = per_cpu_ptr(calxeda_idle_cpuidle_devices, cpu_id);
		dev->cpu = cpu_id;
		dev->state_count = drv->state_count;

		ret = cpuidle_register_device(dev);
		if (ret) {
		pr_err("Failed to register cpu %u, error: %d\n",
		cpu_id, ret);
		goto uninit;
		}
		}

		return 0;

		uninit:
		calxeda_idle_cpuidle_devices_uninit();
		unregister_drv:
		cpuidle_unregister_driver(drv);
		return ret;
		}
		module_init(calxeda_cpuidle_init);