[mirror_ubuntu-artful-kernel.git] / drivers / cpufreq / ppc_cbe_cpufreq_pmi.c

/*
 * pmi backend for the cbe_cpufreq driver
 *
 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
 *
 * Author: Christian Krafft <krafft@de.ibm.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, 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <linux/of_platform.h>

#include <asm/processor.h>
#include <asm/prom.h>
#include <asm/pmi.h>
#include <asm/cell-regs.h>

#ifdef DEBUG
#include <asm/time.h>
#endif

#include "ppc_cbe_cpufreq.h"

static u8 pmi_slow_mode_limit[MAX_CBE];

bool cbe_cpufreq_has_pmi = false;
EXPORT_SYMBOL_GPL(cbe_cpufreq_has_pmi);

/*
 * hardware specific functions
 */

int cbe_cpufreq_set_pmode_pmi(int cpu, unsigned int pmode)
{
	int ret;
	pmi_message_t pmi_msg;
#ifdef DEBUG
	long time;
#endif
	pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
	pmi_msg.data1 =	cbe_cpu_to_node(cpu);
	pmi_msg.data2 = pmode;

#ifdef DEBUG
	time = jiffies;
#endif
	pmi_send_message(pmi_msg);

#ifdef DEBUG
	time = jiffies  - time;
	time = jiffies_to_msecs(time);
	pr_debug("had to wait %lu ms for a transition using " \
		 "PMI\n", time);
#endif
	ret = pmi_msg.data2;
	pr_debug("PMI returned slow mode %d\n", ret);

	return ret;
}
EXPORT_SYMBOL_GPL(cbe_cpufreq_set_pmode_pmi);


static void cbe_cpufreq_handle_pmi(pmi_message_t pmi_msg)
{
	u8 node, slow_mode;

	BUG_ON(pmi_msg.type != PMI_TYPE_FREQ_CHANGE);

	node = pmi_msg.data1;
	slow_mode = pmi_msg.data2;

	pmi_slow_mode_limit[node] = slow_mode;

	pr_debug("cbe_handle_pmi: node: %d max_freq: %d\n", node, slow_mode);
}

static int pmi_notifier(struct notifier_block *nb,
				       unsigned long event, void *data)
{
	struct cpufreq_policy *policy = data;
	struct cpufreq_frequency_table *cbe_freqs = policy->freq_table;
	u8 node;

	/* Should this really be called for CPUFREQ_ADJUST and CPUFREQ_NOTIFY
	 * policy events?)
	 */
	node = cbe_cpu_to_node(policy->cpu);

	pr_debug("got notified, event=%lu, node=%u\n", event, node);

	if (pmi_slow_mode_limit[node] != 0) {
		pr_debug("limiting node %d to slow mode %d\n",
			 node, pmi_slow_mode_limit[node]);

		cpufreq_verify_within_limits(policy, 0,

			cbe_freqs[pmi_slow_mode_limit[node]].frequency);
	}

	return 0;
}

static struct notifier_block pmi_notifier_block = {
	.notifier_call = pmi_notifier,
};

static struct pmi_handler cbe_pmi_handler = {
	.type			= PMI_TYPE_FREQ_CHANGE,
	.handle_pmi_message	= cbe_cpufreq_handle_pmi,
};


static int __init cbe_cpufreq_pmi_init(void)
{
	cbe_cpufreq_has_pmi = pmi_register_handler(&cbe_pmi_handler) == 0;

	if (!cbe_cpufreq_has_pmi)
		return -ENODEV;

	cpufreq_register_notifier(&pmi_notifier_block, CPUFREQ_POLICY_NOTIFIER);

	return 0;
}
device_initcall(cbe_cpufreq_pmi_init);
Commit	Line	Data
74889e41 CK	1	/*
	2	* pmi backend for the cbe_cpufreq driver
	3	*
	4	* (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
	5	*
	6	* Author: Christian Krafft <krafft@de.ibm.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2, or (at your option)
	11	* any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	21	*/
	22
	23	#include <linux/kernel.h>
	24	#include <linux/types.h>
	25	#include <linux/timer.h>
dbbe972c	26	#include <linux/init.h>
d8caf74f JL	27	#include <linux/of_platform.h>
d8caf74f JL	28
74889e41 CK	29	#include <asm/processor.h>
	30	#include <asm/prom.h>
	31	#include <asm/pmi.h>
eef686a0	32	#include <asm/cell-regs.h>
74889e41 CK	33
	34	#ifdef DEBUG
	35	#include <asm/time.h>
	36	#endif
	37
6eb1c377	38	#include "ppc_cbe_cpufreq.h"
74889e41 CK	39
	40	static u8 pmi_slow_mode_limit[MAX_CBE];
	41
	42	bool cbe_cpufreq_has_pmi = false;
	43	EXPORT_SYMBOL_GPL(cbe_cpufreq_has_pmi);
	44
	45	/*
	46	* hardware specific functions
	47	*/
	48
	49	int cbe_cpufreq_set_pmode_pmi(int cpu, unsigned int pmode)
	50	{
	51	int ret;
	52	pmi_message_t pmi_msg;
	53	#ifdef DEBUG
	54	long time;
	55	#endif
	56	pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
	57	pmi_msg.data1 = cbe_cpu_to_node(cpu);
	58	pmi_msg.data2 = pmode;
	59
	60	#ifdef DEBUG
	61	time = jiffies;
	62	#endif
	63	pmi_send_message(pmi_msg);
	64
	65	#ifdef DEBUG
	66	time = jiffies - time;
	67	time = jiffies_to_msecs(time);
	68	pr_debug("had to wait %lu ms for a transition using " \
	69	"PMI\n", time);
	70	#endif
	71	ret = pmi_msg.data2;
	72	pr_debug("PMI returned slow mode %d\n", ret);
	73
	74	return ret;
	75	}
	76	EXPORT_SYMBOL_GPL(cbe_cpufreq_set_pmode_pmi);
	77
	78
	79	static void cbe_cpufreq_handle_pmi(pmi_message_t pmi_msg)
	80	{
	81	u8 node, slow_mode;
	82
	83	BUG_ON(pmi_msg.type != PMI_TYPE_FREQ_CHANGE);
	84
	85	node = pmi_msg.data1;
	86	slow_mode = pmi_msg.data2;
	87
	88	pmi_slow_mode_limit[node] = slow_mode;
	89
	90	pr_debug("cbe_handle_pmi: node: %d max_freq: %d\n", node, slow_mode);
	91	}
	92
	93	static int pmi_notifier(struct notifier_block *nb,
	94	unsigned long event, void *data)
	95	{
	96	struct cpufreq_policy *policy = data;
f8bfc116	97	struct cpufreq_frequency_table *cbe_freqs = policy->freq_table;
74889e41 CK	98	u8 node;
74889e41 CK	99
6bfb7c74 VK	100	/* Should this really be called for CPUFREQ_ADJUST and CPUFREQ_NOTIFY
6bfb7c74 VK	101	* policy events?)
a1531acd	102	*/
74889e41 CK	103	node = cbe_cpu_to_node(policy->cpu);
	104
	105	pr_debug("got notified, event=%lu, node=%u\n", event, node);
	106
	107	if (pmi_slow_mode_limit[node] != 0) {
	108	pr_debug("limiting node %d to slow mode %d\n",
	109	node, pmi_slow_mode_limit[node]);
	110
	111	cpufreq_verify_within_limits(policy, 0,
	112
	113	cbe_freqs[pmi_slow_mode_limit[node]].frequency);
	114	}
	115
	116	return 0;
	117	}
	118
	119	static struct notifier_block pmi_notifier_block = {
	120	.notifier_call = pmi_notifier,
	121	};
	122
	123	static struct pmi_handler cbe_pmi_handler = {
	124	.type = PMI_TYPE_FREQ_CHANGE,
	125	.handle_pmi_message = cbe_cpufreq_handle_pmi,
	126	};
	127
	128
	129
	130	static int __init cbe_cpufreq_pmi_init(void)
	131	{
	132	cbe_cpufreq_has_pmi = pmi_register_handler(&cbe_pmi_handler) == 0;
	133
	134	if (!cbe_cpufreq_has_pmi)
	135	return -ENODEV;
	136
	137	cpufreq_register_notifier(&pmi_notifier_block, CPUFREQ_POLICY_NOTIFIER);
	138
	139	return 0;
	140	}
dbbe972c	141	device_initcall(cbe_cpufreq_pmi_init);