linux/drivers/cpufreq/arm_big_little.h
Viresh Kumar 8a67f0ef2b cpufreq: ARM big LITTLE: Add generic cpufreq driver and its DT glue
big LITTLE is ARM's new Architecture focussing power/performance needs of modern
world. More information about big LITTLE can be found here:

http://www.arm.com/products/processors/technologies/biglittleprocessing.php
http://lwn.net/Articles/481055/

In order to keep cpufreq support for all big LITTLE platforms simple/generic,
this patch tries to add a generic cpufreq driver layer for all big LITTLE
platforms.

The driver is divided into two parts:
- Core driver: Generic and shared across all big LITTLE SoC's
- Glue drivers: Per platform drivers providing ops to the core driver

This patch adds in a generic glue driver which would extract information from
Device Tree.

Future SoC's can either reuse the DT glue or write their own depending on the
need.

Signed-off-by: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-04-02 15:26:32 +02:00

41 lines
1.2 KiB
C

/*
* ARM big.LITTLE platform's CPUFreq header file
*
* Copyright (C) 2013 ARM Ltd.
* Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com>
*
* Copyright (C) 2013 Linaro.
* Viresh Kumar <viresh.kumar@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef CPUFREQ_ARM_BIG_LITTLE_H
#define CPUFREQ_ARM_BIG_LITTLE_H
#include <linux/cpufreq.h>
#include <linux/device.h>
#include <linux/types.h>
struct cpufreq_arm_bL_ops {
char name[CPUFREQ_NAME_LEN];
int (*get_transition_latency)(struct device *cpu_dev);
/*
* This must set opp table for cpu_dev in a similar way as done by
* of_init_opp_table().
*/
int (*init_opp_table)(struct device *cpu_dev);
};
int bL_cpufreq_register(struct cpufreq_arm_bL_ops *ops);
void bL_cpufreq_unregister(struct cpufreq_arm_bL_ops *ops);
#endif /* CPUFREQ_ARM_BIG_LITTLE_H */