[net-next-2.6.git] / arch / x86 / kernel / cpu / cpufreq / powernow-k6.c

/*
 *  This file was based upon code in Powertweak Linux (http://powertweak.sf.net)
 *  (C) 2000-2003  Dave Jones, Arjan van de Ven, Janne Pänkälä, Dominik Brodowski.
 *
 *  Licensed under the terms of the GNU GPL License version 2.
 *
 *  BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous*
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <linux/ioport.h>
#include <linux/slab.h>

#include <asm/msr.h>
#include <linux/timex.h>
#include <linux/io.h>

#define POWERNOW_IOPORT 0xfff0          /* it doesn't matter where, as long
					   as it is unused */

static unsigned int                     busfreq;   /* FSB, in 10 kHz */
static unsigned int                     max_multiplier;


/* Clock ratio multiplied by 10 - see table 27 in AMD#23446 */
static struct cpufreq_frequency_table clock_ratio[] = {
	{45,  /* 000 -> 4.5x */ 0},
	{50,  /* 001 -> 5.0x */ 0},
	{40,  /* 010 -> 4.0x */ 0},
	{55,  /* 011 -> 5.5x */ 0},
	{20,  /* 100 -> 2.0x */ 0},
	{30,  /* 101 -> 3.0x */ 0},
	{60,  /* 110 -> 6.0x */ 0},
	{35,  /* 111 -> 3.5x */ 0},
	{0, CPUFREQ_TABLE_END}
};


/**
 * powernow_k6_get_cpu_multiplier - returns the current FSB multiplier
 *
 *   Returns the current setting of the frequency multiplier. Core clock
 * speed is frequency of the Front-Side Bus multiplied with this value.
 */
static int powernow_k6_get_cpu_multiplier(void)
{
	u64             invalue = 0;
	u32             msrval;

	msrval = POWERNOW_IOPORT + 0x1;
	wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
	invalue = inl(POWERNOW_IOPORT + 0x8);
	msrval = POWERNOW_IOPORT + 0x0;
	wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */

	return clock_ratio[(invalue >> 5)&7].index;
}


/**
 * powernow_k6_set_state - set the PowerNow! multiplier
 * @best_i: clock_ratio[best_i] is the target multiplier
 *
 *   Tries to change the PowerNow! multiplier
 */
static void powernow_k6_set_state(unsigned int best_i)
{
	unsigned long           outvalue = 0, invalue = 0;
	unsigned long           msrval;
	struct cpufreq_freqs    freqs;

	if (clock_ratio[best_i].index > max_multiplier) {
		printk(KERN_ERR "cpufreq: invalid target frequency\n");
		return;
	}

	freqs.old = busfreq * powernow_k6_get_cpu_multiplier();
	freqs.new = busfreq * clock_ratio[best_i].index;
	freqs.cpu = 0; /* powernow-k6.c is UP only driver */

	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);

	/* we now need to transform best_i to the BVC format, see AMD#23446 */

	outvalue = (1<<12) | (1<<10) | (1<<9) | (best_i<<5);

	msrval = POWERNOW_IOPORT + 0x1;
	wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
	invalue = inl(POWERNOW_IOPORT + 0x8);
	invalue = invalue & 0xf;
	outvalue = outvalue | invalue;
	outl(outvalue , (POWERNOW_IOPORT + 0x8));
	msrval = POWERNOW_IOPORT + 0x0;
	wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */

	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);

	return;
}


/**
 * powernow_k6_verify - verifies a new CPUfreq policy
 * @policy: new policy
 *
 * Policy must be within lowest and highest possible CPU Frequency,
 * and at least one possible state must be within min and max.
 */
static int powernow_k6_verify(struct cpufreq_policy *policy)
{
	return cpufreq_frequency_table_verify(policy, &clock_ratio[0]);
}


/**
 * powernow_k6_setpolicy - sets a new CPUFreq policy
 * @policy: new policy
 * @target_freq: the target frequency
 * @relation: how that frequency relates to achieved frequency (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H)
 *
 * sets a new CPUFreq policy
 */
static int powernow_k6_target(struct cpufreq_policy *policy,
			       unsigned int target_freq,
			       unsigned int relation)
{
	unsigned int    newstate = 0;

	if (cpufreq_frequency_table_target(policy, &clock_ratio[0], target_freq, relation, &newstate))
		return -EINVAL;

	powernow_k6_set_state(newstate);

	return 0;
}


static int powernow_k6_cpu_init(struct cpufreq_policy *policy)
{
	unsigned int i;
	int result;

	if (policy->cpu != 0)
		return -ENODEV;

	/* get frequencies */
	max_multiplier = powernow_k6_get_cpu_multiplier();
	busfreq = cpu_khz / max_multiplier;

	/* table init */
	for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {
		if (clock_ratio[i].index > max_multiplier)
			clock_ratio[i].frequency = CPUFREQ_ENTRY_INVALID;
		else
			clock_ratio[i].frequency = busfreq * clock_ratio[i].index;
	}

	/* cpuinfo and default policy values */
	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
	policy->cur = busfreq * max_multiplier;

	result = cpufreq_frequency_table_cpuinfo(policy, clock_ratio);
	if (result)
		return result;

	cpufreq_frequency_table_get_attr(clock_ratio, policy->cpu);

	return 0;
}


static int powernow_k6_cpu_exit(struct cpufreq_policy *policy)
{
	unsigned int i;
	for (i = 0; i < 8; i++) {
		if (i == max_multiplier)
			powernow_k6_set_state(i);
	}
	cpufreq_frequency_table_put_attr(policy->cpu);
	return 0;
}

static unsigned int powernow_k6_get(unsigned int cpu)
{
	return busfreq * powernow_k6_get_cpu_multiplier();
}

static struct freq_attr *powernow_k6_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
	NULL,
};

static struct cpufreq_driver powernow_k6_driver = {
	.verify		= powernow_k6_verify,
	.target		= powernow_k6_target,
	.init		= powernow_k6_cpu_init,
	.exit		= powernow_k6_cpu_exit,
	.get		= powernow_k6_get,
	.name		= "powernow-k6",
	.owner		= THIS_MODULE,
	.attr		= powernow_k6_attr,
};


/**
 * powernow_k6_init - initializes the k6 PowerNow! CPUFreq driver
 *
 *   Initializes the K6 PowerNow! support. Returns -ENODEV on unsupported
 * devices, -EINVAL or -ENOMEM on problems during initiatization, and zero
 * on success.
 */
static int __init powernow_k6_init(void)
{
	struct cpuinfo_x86 *c = &cpu_data(0);

	if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 != 5) ||
		((c->x86_model != 12) && (c->x86_model != 13)))
		return -ENODEV;

	if (!request_region(POWERNOW_IOPORT, 16, "PowerNow!")) {
		printk("cpufreq: PowerNow IOPORT region already used.\n");
		return -EIO;
	}

	if (cpufreq_register_driver(&powernow_k6_driver)) {
		release_region(POWERNOW_IOPORT, 16);
		return -EINVAL;
	}

	return 0;
}


/**
 * powernow_k6_exit - unregisters AMD K6-2+/3+ PowerNow! support
 *
 *   Unregisters AMD K6-2+ / K6-3+ PowerNow! support.
 */
static void __exit powernow_k6_exit(void)
{
	cpufreq_unregister_driver(&powernow_k6_driver);
	release_region(POWERNOW_IOPORT, 16);
}


MODULE_AUTHOR("Arjan van de Ven, Dave Jones <davej@redhat.com>, Dominik Brodowski <linux@brodo.de>");
MODULE_DESCRIPTION("PowerNow! driver for AMD K6-2+ / K6-3+ processors.");
MODULE_LICENSE("GPL");

module_init(powernow_k6_init);
module_exit(powernow_k6_exit);
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* This file was based upon code in Powertweak Linux (http://powertweak.sf.net)
96de0e25	3	* (C) 2000-2003 Dave Jones, Arjan van de Ven, Janne Pänkälä, Dominik Brodowski.
1da177e4 LT	4	*
	5	* Licensed under the terms of the GNU GPL License version 2.
	6	*
	7	* BIG FAT DISCLAIMER: Work in progress code. Possibly dangerous
	8	*/
	9
	10	#include <linux/kernel.h>
32ee8c3e	11	#include <linux/module.h>
1da177e4 LT	12	#include <linux/init.h>
	13	#include <linux/cpufreq.h>
	14	#include <linux/ioport.h>
	15	#include <linux/slab.h>
	16
	17	#include <asm/msr.h>
8d2d2051 PC	18	#include <linux/timex.h>
8d2d2051 PC	19	#include <linux/io.h>
1da177e4	20
8d2d2051 PC	21	#define POWERNOW_IOPORT 0xfff0 /* it doesn't matter where, as long
8d2d2051 PC	22	as it is unused */
1da177e4 LT	23
	24	static unsigned int busfreq; /* FSB, in 10 kHz */
	25	static unsigned int max_multiplier;
	26
	27
	28	/* Clock ratio multiplied by 10 - see table 27 in AMD#23446 */
	29	static struct cpufreq_frequency_table clock_ratio[] = {
	30	{45, /* 000 -> 4.5x */ 0},
	31	{50, /* 001 -> 5.0x */ 0},
	32	{40, /* 010 -> 4.0x */ 0},
	33	{55, /* 011 -> 5.5x */ 0},
	34	{20, /* 100 -> 2.0x */ 0},
	35	{30, /* 101 -> 3.0x */ 0},
	36	{60, /* 110 -> 6.0x */ 0},
	37	{35, /* 111 -> 3.5x */ 0},
	38	{0, CPUFREQ_TABLE_END}
	39	};
	40
	41
	42	/**
	43	* powernow_k6_get_cpu_multiplier - returns the current FSB multiplier
	44	*
	45	* Returns the current setting of the frequency multiplier. Core clock
	46	* speed is frequency of the Front-Side Bus multiplied with this value.
	47	*/
	48	static int powernow_k6_get_cpu_multiplier(void)
	49	{
	50	u64 invalue = 0;
	51	u32 msrval;
32ee8c3e	52
1da177e4 LT	53	msrval = POWERNOW_IOPORT + 0x1;
1da177e4 LT	54	wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
8d2d2051	55	invalue = inl(POWERNOW_IOPORT + 0x8);
1da177e4 LT	56	msrval = POWERNOW_IOPORT + 0x0;
	57	wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */
	58
	59	return clock_ratio[(invalue >> 5)&7].index;
	60	}
	61
	62
	63	/**
	64	* powernow_k6_set_state - set the PowerNow! multiplier
	65	* @best_i: clock_ratio[best_i] is the target multiplier
	66	*
	67	* Tries to change the PowerNow! multiplier
	68	*/
8d2d2051	69	static void powernow_k6_set_state(unsigned int best_i)
1da177e4	70	{
8d2d2051	71	unsigned long outvalue = 0, invalue = 0;
1da177e4 LT	72	unsigned long msrval;
	73	struct cpufreq_freqs freqs;
	74
	75	if (clock_ratio[best_i].index > max_multiplier) {
	76	printk(KERN_ERR "cpufreq: invalid target frequency\n");
	77	return;
	78	}
	79
	80	freqs.old = busfreq * powernow_k6_get_cpu_multiplier();
	81	freqs.new = busfreq * clock_ratio[best_i].index;
	82	freqs.cpu = 0; /* powernow-k6.c is UP only driver */
32ee8c3e	83
1da177e4 LT	84	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
	85
	86	/* we now need to transform best_i to the BVC format, see AMD#23446 */
	87
	88	outvalue = (1<<12) \| (1<<10) \| (1<<9) \| (best_i<<5);
	89
	90	msrval = POWERNOW_IOPORT + 0x1;
	91	wrmsr(MSR_K6_EPMR, msrval, 0); /* enable the PowerNow port */
8d2d2051	92	invalue = inl(POWERNOW_IOPORT + 0x8);
1da177e4 LT	93	invalue = invalue & 0xf;
1da177e4 LT	94	outvalue = outvalue \| invalue;
8d2d2051	95	outl(outvalue , (POWERNOW_IOPORT + 0x8));
1da177e4 LT	96	msrval = POWERNOW_IOPORT + 0x0;
	97	wrmsr(MSR_K6_EPMR, msrval, 0); /* disable it again */
	98
	99	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
	100
	101	return;
	102	}
	103
	104
	105	/**
	106	* powernow_k6_verify - verifies a new CPUfreq policy
	107	* @policy: new policy
	108	*
	109	* Policy must be within lowest and highest possible CPU Frequency,
	110	* and at least one possible state must be within min and max.
	111	*/
	112	static int powernow_k6_verify(struct cpufreq_policy *policy)
	113	{
	114	return cpufreq_frequency_table_verify(policy, &clock_ratio[0]);
	115	}
	116
	117
	118	/**
	119	* powernow_k6_setpolicy - sets a new CPUFreq policy
	120	* @policy: new policy
	121	* @target_freq: the target frequency
	122	* @relation: how that frequency relates to achieved frequency (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H)
	123	*
	124	* sets a new CPUFreq policy
	125	*/
8d2d2051	126	static int powernow_k6_target(struct cpufreq_policy *policy,
1da177e4 LT	127	unsigned int target_freq,
	128	unsigned int relation)
	129	{
	130	unsigned int newstate = 0;
	131
	132	if (cpufreq_frequency_table_target(policy, &clock_ratio[0], target_freq, relation, &newstate))
	133	return -EINVAL;
	134
	135	powernow_k6_set_state(newstate);
	136
	137	return 0;
	138	}
	139
	140
	141	static int powernow_k6_cpu_init(struct cpufreq_policy *policy)
	142	{
	143	unsigned int i;
	144	int result;
	145
	146	if (policy->cpu != 0)
	147	return -ENODEV;
	148
	149	/* get frequencies */
	150	max_multiplier = powernow_k6_get_cpu_multiplier();
	151	busfreq = cpu_khz / max_multiplier;
	152
	153	/* table init */
8d2d2051	154	for (i = 0; (clock_ratio[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	155	if (clock_ratio[i].index > max_multiplier)
	156	clock_ratio[i].frequency = CPUFREQ_ENTRY_INVALID;
	157	else
	158	clock_ratio[i].frequency = busfreq * clock_ratio[i].index;
	159	}
	160
	161	/* cpuinfo and default policy values */
1da177e4 LT	162	policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
	163	policy->cur = busfreq * max_multiplier;
	164
	165	result = cpufreq_frequency_table_cpuinfo(policy, clock_ratio);
	166	if (result)
8d2d2051	167	return result;
1da177e4 LT	168
	169	cpufreq_frequency_table_get_attr(clock_ratio, policy->cpu);
	170
	171	return 0;
	172	}
	173
	174
	175	static int powernow_k6_cpu_exit(struct cpufreq_policy *policy)
	176	{
	177	unsigned int i;
8d2d2051 PC	178	for (i = 0; i < 8; i++) {
8d2d2051 PC	179	if (i == max_multiplier)
1da177e4 LT	180	powernow_k6_set_state(i);
	181	}
	182	cpufreq_frequency_table_put_attr(policy->cpu);
32ee8c3e	183	return 0;
1da177e4 LT	184	}
	185
	186	static unsigned int powernow_k6_get(unsigned int cpu)
	187	{
	188	return busfreq * powernow_k6_get_cpu_multiplier();
	189	}
	190
8d2d2051	191	static struct freq_attr *powernow_k6_attr[] = {
1da177e4 LT	192	&cpufreq_freq_attr_scaling_available_freqs,
	193	NULL,
	194	};
	195
221dee28	196	static struct cpufreq_driver powernow_k6_driver = {
32ee8c3e DJ	197	.verify = powernow_k6_verify,
32ee8c3e DJ	198	.target = powernow_k6_target,
1da177e4 LT	199	.init = powernow_k6_cpu_init,
	200	.exit = powernow_k6_cpu_exit,
	201	.get = powernow_k6_get,
	202	.name = "powernow-k6",
	203	.owner = THIS_MODULE,
	204	.attr = powernow_k6_attr,
	205	};
	206
	207
	208	/**
	209	* powernow_k6_init - initializes the k6 PowerNow! CPUFreq driver
	210	*
	211	* Initializes the K6 PowerNow! support. Returns -ENODEV on unsupported
	212	* devices, -EINVAL or -ENOMEM on problems during initiatization, and zero
	213	* on success.
	214	*/
	215	static int __init powernow_k6_init(void)
32ee8c3e	216	{
92cb7612	217	struct cpuinfo_x86 *c = &cpu_data(0);
1da177e4 LT	218
	219	if ((c->x86_vendor != X86_VENDOR_AMD) \|\| (c->x86 != 5) \|\|
	220	((c->x86_model != 12) && (c->x86_model != 13)))
	221	return -ENODEV;
	222
	223	if (!request_region(POWERNOW_IOPORT, 16, "PowerNow!")) {
	224	printk("cpufreq: PowerNow IOPORT region already used.\n");
	225	return -EIO;
	226	}
	227
	228	if (cpufreq_register_driver(&powernow_k6_driver)) {
8d2d2051	229	release_region(POWERNOW_IOPORT, 16);
1da177e4 LT	230	return -EINVAL;
	231	}
	232
	233	return 0;
	234	}
	235
	236
	237	/**
	238	* powernow_k6_exit - unregisters AMD K6-2+/3+ PowerNow! support
	239	*
	240	* Unregisters AMD K6-2+ / K6-3+ PowerNow! support.
	241	*/
	242	static void __exit powernow_k6_exit(void)
	243	{
	244	cpufreq_unregister_driver(&powernow_k6_driver);
8d2d2051	245	release_region(POWERNOW_IOPORT, 16);
1da177e4 LT	246	}
	247
	248
f4432c5c	249	MODULE_AUTHOR("Arjan van de Ven, Dave Jones <davej@redhat.com>, Dominik Brodowski <linux@brodo.de>");
8d2d2051 PC	250	MODULE_DESCRIPTION("PowerNow! driver for AMD K6-2+ / K6-3+ processors.");
8d2d2051 PC	251	MODULE_LICENSE("GPL");
1da177e4 LT	252
	253	module_init(powernow_k6_init);
	254	module_exit(powernow_k6_exit);