[linux-block.git] / drivers / cpufreq / ppc_cbe_cpufreq_pmi.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * pmi backend for the cbe_cpufreq driver
 *
 * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
 *
 * Author: Christian Krafft <krafft@de.ibm.com>
 */

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

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

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

#include "ppc_cbe_cpufreq.h"

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)
{
	struct cpufreq_policy *policy;
	struct freq_qos_request *req;
	u8 node, slow_mode;
	int cpu, ret;

	BUG_ON(pmi_msg.type != PMI_TYPE_FREQ_CHANGE);

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

	cpu = cbe_node_to_cpu(node);

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

	policy = cpufreq_cpu_get(cpu);
	if (!policy) {
		pr_warn("cpufreq policy not found cpu%d\n", cpu);
		return;
	}

	req = policy->driver_data;

	ret = freq_qos_update_request(req,
			policy->freq_table[slow_mode].frequency);
	if (ret < 0)
		pr_warn("Failed to update freq constraint: %d\n", ret);
	else
		pr_debug("limiting node %d to slow mode %d\n", node, slow_mode);

	cpufreq_cpu_put(policy);
}

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

void cbe_cpufreq_pmi_policy_init(struct cpufreq_policy *policy)
{
	struct freq_qos_request *req;
	int ret;

	if (!cbe_cpufreq_has_pmi)
		return;

	req = kzalloc(sizeof(*req), GFP_KERNEL);
	if (!req)
		return;

	ret = freq_qos_add_request(&policy->constraints, req, FREQ_QOS_MAX,
				   policy->freq_table[0].frequency);
	if (ret < 0) {
		pr_err("Failed to add freq constraint (%d)\n", ret);
		kfree(req);
		return;
	}

	policy->driver_data = req;
}
EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_policy_init);

void cbe_cpufreq_pmi_policy_exit(struct cpufreq_policy *policy)
{
	struct freq_qos_request *req = policy->driver_data;

	if (cbe_cpufreq_has_pmi) {
		freq_qos_remove_request(req);
		kfree(req);
	}
}
EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_policy_exit);

void cbe_cpufreq_pmi_init(void)
{
	if (!pmi_register_handler(&cbe_pmi_handler))
		cbe_cpufreq_has_pmi = true;
}
EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_init);

void cbe_cpufreq_pmi_exit(void)
{
	pmi_unregister_handler(&cbe_pmi_handler);
	cbe_cpufreq_has_pmi = false;
}
EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_exit);
Commit	Line	Data
de6cc651	1	// SPDX-License-Identifier: GPL-2.0-or-later
74889e41 CK	2	/*
	3	* pmi backend for the cbe_cpufreq driver
	4	*
	5	* (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
	6	*
	7	* Author: Christian Krafft <krafft@de.ibm.com>
74889e41 CK	8	*/
	9
	10	#include <linux/kernel.h>
	11	#include <linux/types.h>
	12	#include <linux/timer.h>
dbbe972c	13	#include <linux/init.h>
d8caf74f	14	#include <linux/of_platform.h>
afe96907	15	#include <linux/pm_qos.h>
95996a67	16	#include <linux/slab.h>
d8caf74f	17
74889e41	18	#include <asm/processor.h>
74889e41	19	#include <asm/pmi.h>
eef686a0	20	#include <asm/cell-regs.h>
74889e41 CK	21
	22	#ifdef DEBUG
	23	#include <asm/time.h>
	24	#endif
	25
6eb1c377	26	#include "ppc_cbe_cpufreq.h"
74889e41	27
74889e41 CK	28	bool cbe_cpufreq_has_pmi = false;
	29	EXPORT_SYMBOL_GPL(cbe_cpufreq_has_pmi);
	30
	31	/*
	32	* hardware specific functions
	33	*/
	34
	35	int cbe_cpufreq_set_pmode_pmi(int cpu, unsigned int pmode)
	36	{
	37	int ret;
	38	pmi_message_t pmi_msg;
	39	#ifdef DEBUG
	40	long time;
	41	#endif
	42	pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
	43	pmi_msg.data1 = cbe_cpu_to_node(cpu);
	44	pmi_msg.data2 = pmode;
	45
	46	#ifdef DEBUG
	47	time = jiffies;
	48	#endif
	49	pmi_send_message(pmi_msg);
	50
	51	#ifdef DEBUG
	52	time = jiffies - time;
	53	time = jiffies_to_msecs(time);
	54	pr_debug("had to wait %lu ms for a transition using " \
	55	"PMI\n", time);
	56	#endif
	57	ret = pmi_msg.data2;
	58	pr_debug("PMI returned slow mode %d\n", ret);
	59
	60	return ret;
	61	}
	62	EXPORT_SYMBOL_GPL(cbe_cpufreq_set_pmode_pmi);
	63
	64
	65	static void cbe_cpufreq_handle_pmi(pmi_message_t pmi_msg)
	66	{
afe96907	67	struct cpufreq_policy *policy;
3000ce3c	68	struct freq_qos_request *req;
74889e41	69	u8 node, slow_mode;
afe96907	70	int cpu, ret;
74889e41 CK	71
	72	BUG_ON(pmi_msg.type != PMI_TYPE_FREQ_CHANGE);
	73
	74	node = pmi_msg.data1;
	75	slow_mode = pmi_msg.data2;
	76
afe96907	77	cpu = cbe_node_to_cpu(node);
74889e41 CK	78
74889e41 CK	79	pr_debug("cbe_handle_pmi: node: %d max_freq: %d\n", node, slow_mode);
74889e41	80
afe96907 VK	81	policy = cpufreq_cpu_get(cpu);
	82	if (!policy) {
	83	pr_warn("cpufreq policy not found cpu%d\n", cpu);
	84	return;
	85	}
74889e41	86
afe96907	87	req = policy->driver_data;
74889e41	88
3000ce3c	89	ret = freq_qos_update_request(req,
afe96907 VK	90	policy->freq_table[slow_mode].frequency);
	91	if (ret < 0)
	92	pr_warn("Failed to update freq constraint: %d\n", ret);
	93	else
	94	pr_debug("limiting node %d to slow mode %d\n", node, slow_mode);
74889e41	95
afe96907	96	cpufreq_cpu_put(policy);
74889e41 CK	97	}
74889e41 CK	98
74889e41 CK	99	static struct pmi_handler cbe_pmi_handler = {
	100	.type = PMI_TYPE_FREQ_CHANGE,
	101	.handle_pmi_message = cbe_cpufreq_handle_pmi,
	102	};
	103
afe96907 VK	104	void cbe_cpufreq_pmi_policy_init(struct cpufreq_policy *policy)
afe96907 VK	105	{
3000ce3c	106	struct freq_qos_request *req;
afe96907 VK	107	int ret;
	108
	109	if (!cbe_cpufreq_has_pmi)
	110	return;
	111
	112	req = kzalloc(sizeof(*req), GFP_KERNEL);
	113	if (!req)
	114	return;
	115
3000ce3c RW	116	ret = freq_qos_add_request(&policy->constraints, req, FREQ_QOS_MAX,
3000ce3c RW	117	policy->freq_table[0].frequency);
afe96907 VK	118	if (ret < 0) {
	119	pr_err("Failed to add freq constraint (%d)\n", ret);
	120	kfree(req);
	121	return;
	122	}
74889e41	123
afe96907 VK	124	policy->driver_data = req;
	125	}
	126	EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_policy_init);
74889e41	127
afe96907	128	void cbe_cpufreq_pmi_policy_exit(struct cpufreq_policy *policy)
74889e41	129	{
3000ce3c	130	struct freq_qos_request *req = policy->driver_data;
74889e41	131
afe96907	132	if (cbe_cpufreq_has_pmi) {
3000ce3c	133	freq_qos_remove_request(req);
afe96907 VK	134	kfree(req);
	135	}
	136	}
	137	EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_policy_exit);
74889e41	138
afe96907 VK	139	void cbe_cpufreq_pmi_init(void)
	140	{
	141	if (!pmi_register_handler(&cbe_pmi_handler))
	142	cbe_cpufreq_has_pmi = true;
	143	}
	144	EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_init);
74889e41	145
afe96907 VK	146	void cbe_cpufreq_pmi_exit(void)
	147	{
	148	pmi_unregister_handler(&cbe_pmi_handler);
	149	cbe_cpufreq_has_pmi = false;
74889e41	150	}
afe96907	151	EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_exit);