151 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			151 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-or-later
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| /*
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|  * pmi backend for the cbe_cpufreq driver
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|  *
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|  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005-2007
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|  *
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|  * Author: Christian Krafft <krafft@de.ibm.com>
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/types.h>
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| #include <linux/timer.h>
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| #include <linux/init.h>
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| #include <linux/pm_qos.h>
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| #include <linux/slab.h>
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| 
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| #include <asm/processor.h>
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| #include <asm/pmi.h>
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| #include <asm/cell-regs.h>
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| 
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| #ifdef DEBUG
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| #include <asm/time.h>
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| #endif
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| 
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| #include "ppc_cbe_cpufreq.h"
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| 
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| bool cbe_cpufreq_has_pmi = false;
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| EXPORT_SYMBOL_GPL(cbe_cpufreq_has_pmi);
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| 
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| /*
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|  * hardware specific functions
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|  */
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| 
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| int cbe_cpufreq_set_pmode_pmi(int cpu, unsigned int pmode)
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| {
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| 	int ret;
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| 	pmi_message_t pmi_msg;
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| #ifdef DEBUG
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| 	long time;
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| #endif
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| 	pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
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| 	pmi_msg.data1 =	cbe_cpu_to_node(cpu);
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| 	pmi_msg.data2 = pmode;
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| 
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| #ifdef DEBUG
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| 	time = jiffies;
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| #endif
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| 	pmi_send_message(pmi_msg);
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| 
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| #ifdef DEBUG
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| 	time = jiffies  - time;
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| 	time = jiffies_to_msecs(time);
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| 	pr_debug("had to wait %lu ms for a transition using " \
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| 		 "PMI\n", time);
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| #endif
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| 	ret = pmi_msg.data2;
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| 	pr_debug("PMI returned slow mode %d\n", ret);
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| 
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| 	return ret;
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| }
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| EXPORT_SYMBOL_GPL(cbe_cpufreq_set_pmode_pmi);
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| 
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| 
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| static void cbe_cpufreq_handle_pmi(pmi_message_t pmi_msg)
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| {
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| 	struct cpufreq_policy *policy;
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| 	struct freq_qos_request *req;
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| 	u8 node, slow_mode;
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| 	int cpu, ret;
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| 
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| 	BUG_ON(pmi_msg.type != PMI_TYPE_FREQ_CHANGE);
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| 
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| 	node = pmi_msg.data1;
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| 	slow_mode = pmi_msg.data2;
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| 
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| 	cpu = cbe_node_to_cpu(node);
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| 
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| 	pr_debug("cbe_handle_pmi: node: %d max_freq: %d\n", node, slow_mode);
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| 
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| 	policy = cpufreq_cpu_get(cpu);
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| 	if (!policy) {
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| 		pr_warn("cpufreq policy not found cpu%d\n", cpu);
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| 		return;
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| 	}
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| 
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| 	req = policy->driver_data;
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| 
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| 	ret = freq_qos_update_request(req,
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| 			policy->freq_table[slow_mode].frequency);
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| 	if (ret < 0)
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| 		pr_warn("Failed to update freq constraint: %d\n", ret);
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| 	else
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| 		pr_debug("limiting node %d to slow mode %d\n", node, slow_mode);
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| 
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| 	cpufreq_cpu_put(policy);
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| }
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| 
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| static struct pmi_handler cbe_pmi_handler = {
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| 	.type			= PMI_TYPE_FREQ_CHANGE,
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| 	.handle_pmi_message	= cbe_cpufreq_handle_pmi,
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| };
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| 
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| void cbe_cpufreq_pmi_policy_init(struct cpufreq_policy *policy)
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| {
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| 	struct freq_qos_request *req;
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| 	int ret;
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| 
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| 	if (!cbe_cpufreq_has_pmi)
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| 		return;
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| 
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| 	req = kzalloc(sizeof(*req), GFP_KERNEL);
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| 	if (!req)
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| 		return;
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| 
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| 	ret = freq_qos_add_request(&policy->constraints, req, FREQ_QOS_MAX,
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| 				   policy->freq_table[0].frequency);
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| 	if (ret < 0) {
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| 		pr_err("Failed to add freq constraint (%d)\n", ret);
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| 		kfree(req);
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| 		return;
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| 	}
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| 
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| 	policy->driver_data = req;
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| }
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| EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_policy_init);
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| 
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| void cbe_cpufreq_pmi_policy_exit(struct cpufreq_policy *policy)
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| {
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| 	struct freq_qos_request *req = policy->driver_data;
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| 
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| 	if (cbe_cpufreq_has_pmi) {
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| 		freq_qos_remove_request(req);
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| 		kfree(req);
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| 	}
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| }
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| EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_policy_exit);
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| 
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| void cbe_cpufreq_pmi_init(void)
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| {
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| 	if (!pmi_register_handler(&cbe_pmi_handler))
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| 		cbe_cpufreq_has_pmi = true;
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| }
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| EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_init);
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| 
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| void cbe_cpufreq_pmi_exit(void)
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| {
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| 	pmi_unregister_handler(&cbe_pmi_handler);
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| 	cbe_cpufreq_has_pmi = false;
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| }
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| EXPORT_SYMBOL_GPL(cbe_cpufreq_pmi_exit);
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