[deliverable/linux.git] / arch / x86 / kernel / cpu / cpufreq / p4-clockmod.c

/*
 *	Pentium 4/Xeon CPU on demand clock modulation/speed scaling
 *	(C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
 *	(C) 2002 Zwane Mwaikambo <zwane@commfireservices.com>
 *	(C) 2002 Arjan van de Ven <arjanv@redhat.com>
 *	(C) 2002 Tora T. Engstad
 *	All Rights Reserved
 *
 *	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 of the License, or (at your option) any later version.
 *
 *      The author(s) of this software shall not be held liable for damages
 *      of any nature resulting due to the use of this software. This
 *      software is provided AS-IS with no warranties.
 *
 *	Date		Errata			Description
 *	20020525	N44, O17	12.5% or 25% DC causes lockup
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/cpufreq.h>
#include <linux/cpumask.h>
#include <linux/timex.h>

#include <asm/processor.h>
#include <asm/msr.h>
#include <asm/timer.h>

#include "speedstep-lib.h"

#define PFX	"p4-clockmod: "
#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
		"p4-clockmod", msg)

/*
 * Duty Cycle (3bits), note DC_DISABLE is not specified in
 * intel docs i just use it to mean disable
 */
enum {
	DC_RESV, DC_DFLT, DC_25PT, DC_38PT, DC_50PT,
	DC_64PT, DC_75PT, DC_88PT, DC_DISABLE
};

#define DC_ENTRIES	8


static int has_N44_O17_errata[NR_CPUS];
static unsigned int stock_freq;
static struct cpufreq_driver p4clockmod_driver;
static unsigned int cpufreq_p4_get(unsigned int cpu);

static int cpufreq_p4_setdc(unsigned int cpu, unsigned int newstate)
{
	u32 l, h;

	if (!cpu_online(cpu) ||
	    (newstate > DC_DISABLE) || (newstate == DC_RESV))
		return -EINVAL;

	rdmsr_on_cpu(cpu, MSR_IA32_THERM_STATUS, &l, &h);

	if (l & 0x01)
		dprintk("CPU#%d currently thermal throttled\n", cpu);

	if (has_N44_O17_errata[cpu] &&
	    (newstate == DC_25PT || newstate == DC_DFLT))
		newstate = DC_38PT;

	rdmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, &l, &h);
	if (newstate == DC_DISABLE) {
		dprintk("CPU#%d disabling modulation\n", cpu);
		wrmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, l & ~(1<<4), h);
	} else {
		dprintk("CPU#%d setting duty cycle to %d%%\n",
			cpu, ((125 * newstate) / 10));
		/* bits 63 - 5	: reserved
		 * bit  4	: enable/disable
		 * bits 3-1	: duty cycle
		 * bit  0	: reserved
		 */
		l = (l & ~14);
		l = l | (1<<4) | ((newstate & 0x7)<<1);
		wrmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, l, h);
	}

	return 0;
}


static struct cpufreq_frequency_table p4clockmod_table[] = {
	{DC_RESV, CPUFREQ_ENTRY_INVALID},
	{DC_DFLT, 0},
	{DC_25PT, 0},
	{DC_38PT, 0},
	{DC_50PT, 0},
	{DC_64PT, 0},
	{DC_75PT, 0},
	{DC_88PT, 0},
	{DC_DISABLE, 0},
	{DC_RESV, CPUFREQ_TABLE_END},
};


static int cpufreq_p4_target(struct cpufreq_policy *policy,
			     unsigned int target_freq,
			     unsigned int relation)
{
	unsigned int    newstate = DC_RESV;
	struct cpufreq_freqs freqs;
	int i;

	if (cpufreq_frequency_table_target(policy, &p4clockmod_table[0],
				target_freq, relation, &newstate))
		return -EINVAL;

	freqs.old = cpufreq_p4_get(policy->cpu);
	freqs.new = stock_freq * p4clockmod_table[newstate].index / 8;

	if (freqs.new == freqs.old)
		return 0;

	/* notifiers */
	for_each_cpu(i, policy->cpus) {
		freqs.cpu = i;
		cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
	}

	/* run on each logical CPU,
	 * see section 13.15.3 of IA32 Intel Architecture Software
	 * Developer's Manual, Volume 3
	 */
	for_each_cpu(i, policy->cpus)
		cpufreq_p4_setdc(i, p4clockmod_table[newstate].index);

	/* notifiers */
	for_each_cpu(i, policy->cpus) {
		freqs.cpu = i;
		cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
	}

	return 0;
}


static int cpufreq_p4_verify(struct cpufreq_policy *policy)
{
	return cpufreq_frequency_table_verify(policy, &p4clockmod_table[0]);
}


static unsigned int cpufreq_p4_get_frequency(struct cpuinfo_x86 *c)
{
	if (c->x86 == 0x06) {
		if (cpu_has(c, X86_FEATURE_EST))
			printk_once(KERN_WARNING PFX "Warning: EST-capable "
			       "CPU detected. The acpi-cpufreq module offers "
			       "voltage scaling in addition to frequency "
			       "scaling. You should use that instead of "
			       "p4-clockmod, if possible.\n");
		switch (c->x86_model) {
		case 0x0E: /* Core */
		case 0x0F: /* Core Duo */
		case 0x16: /* Celeron Core */
		case 0x1C: /* Atom */
			p4clockmod_driver.flags |= CPUFREQ_CONST_LOOPS;
			return speedstep_get_frequency(SPEEDSTEP_CPU_PCORE);
		case 0x0D: /* Pentium M (Dothan) */
			p4clockmod_driver.flags |= CPUFREQ_CONST_LOOPS;
			/* fall through */
		case 0x09: /* Pentium M (Banias) */
			return speedstep_get_frequency(SPEEDSTEP_CPU_PM);
		}
	}

	if (c->x86 != 0xF)
		return 0;

	/* on P-4s, the TSC runs with constant frequency independent whether
	 * throttling is active or not. */
	p4clockmod_driver.flags |= CPUFREQ_CONST_LOOPS;

	if (speedstep_detect_processor() == SPEEDSTEP_CPU_P4M) {
		printk(KERN_WARNING PFX "Warning: Pentium 4-M detected. "
		       "The speedstep-ich or acpi cpufreq modules offer "
		       "voltage scaling in addition of frequency scaling. "
		       "You should use either one instead of p4-clockmod, "
		       "if possible.\n");
		return speedstep_get_frequency(SPEEDSTEP_CPU_P4M);
	}

	return speedstep_get_frequency(SPEEDSTEP_CPU_P4D);
}


static int cpufreq_p4_cpu_init(struct cpufreq_policy *policy)
{
	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
	int cpuid = 0;
	unsigned int i;

#ifdef CONFIG_SMP
	cpumask_copy(policy->cpus, cpu_sibling_mask(policy->cpu));
#endif

	/* Errata workaround */
	cpuid = (c->x86 << 8) | (c->x86_model << 4) | c->x86_mask;
	switch (cpuid) {
	case 0x0f07:
	case 0x0f0a:
	case 0x0f11:
	case 0x0f12:
		has_N44_O17_errata[policy->cpu] = 1;
		dprintk("has errata -- disabling low frequencies\n");
	}

	if (speedstep_detect_processor() == SPEEDSTEP_CPU_P4D &&
	    c->x86_model < 2) {
		/* switch to maximum frequency and measure result */
		cpufreq_p4_setdc(policy->cpu, DC_DISABLE);
		recalibrate_cpu_khz();
	}
	/* get max frequency */
	stock_freq = cpufreq_p4_get_frequency(c);
	if (!stock_freq)
		return -EINVAL;

	/* table init */
	for (i = 1; (p4clockmod_table[i].frequency != CPUFREQ_TABLE_END); i++) {
		if ((i < 2) && (has_N44_O17_errata[policy->cpu]))
			p4clockmod_table[i].frequency = CPUFREQ_ENTRY_INVALID;
		else
			p4clockmod_table[i].frequency = (stock_freq * i)/8;
	}
	cpufreq_frequency_table_get_attr(p4clockmod_table, policy->cpu);

	/* cpuinfo and default policy values */

	/* the transition latency is set to be 1 higher than the maximum
	 * transition latency of the ondemand governor */
	policy->cpuinfo.transition_latency = 10000001;
	policy->cur = stock_freq;

	return cpufreq_frequency_table_cpuinfo(policy, &p4clockmod_table[0]);
}


static int cpufreq_p4_cpu_exit(struct cpufreq_policy *policy)
{
	cpufreq_frequency_table_put_attr(policy->cpu);
	return 0;
}

static unsigned int cpufreq_p4_get(unsigned int cpu)
{
	u32 l, h;

	rdmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, &l, &h);

	if (l & 0x10) {
		l = l >> 1;
		l &= 0x7;
	} else
		l = DC_DISABLE;

	if (l != DC_DISABLE)
		return stock_freq * l / 8;

	return stock_freq;
}

static struct freq_attr *p4clockmod_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
	NULL,
};

static struct cpufreq_driver p4clockmod_driver = {
	.verify		= cpufreq_p4_verify,
	.target		= cpufreq_p4_target,
	.init		= cpufreq_p4_cpu_init,
	.exit		= cpufreq_p4_cpu_exit,
	.get		= cpufreq_p4_get,
	.name		= "p4-clockmod",
	.owner		= THIS_MODULE,
	.attr		= p4clockmod_attr,
};


static int __init cpufreq_p4_init(void)
{
	struct cpuinfo_x86 *c = &cpu_data(0);
	int ret;

	/*
	 * THERM_CONTROL is architectural for IA32 now, so
	 * we can rely on the capability checks
	 */
	if (c->x86_vendor != X86_VENDOR_INTEL)
		return -ENODEV;

	if (!test_cpu_cap(c, X86_FEATURE_ACPI) ||
				!test_cpu_cap(c, X86_FEATURE_ACC))
		return -ENODEV;

	ret = cpufreq_register_driver(&p4clockmod_driver);
	if (!ret)
		printk(KERN_INFO PFX "P4/Xeon(TM) CPU On-Demand Clock "
				"Modulation available\n");

	return ret;
}


static void __exit cpufreq_p4_exit(void)
{
	cpufreq_unregister_driver(&p4clockmod_driver);
}


MODULE_AUTHOR("Zwane Mwaikambo <zwane@commfireservices.com>");
MODULE_DESCRIPTION("cpufreq driver for Pentium(TM) 4/Xeon(TM)");
MODULE_LICENSE("GPL");

late_initcall(cpufreq_p4_init);
module_exit(cpufreq_p4_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Pentium 4/Xeon CPU on demand clock modulation/speed scaling
	3	* (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
	4	* (C) 2002 Zwane Mwaikambo <zwane@commfireservices.com>
	5	* (C) 2002 Arjan van de Ven <arjanv@redhat.com>
	6	* (C) 2002 Tora T. Engstad
	7	* All Rights Reserved
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License
	11	* as published by the Free Software Foundation; either version
	12	* 2 of the License, or (at your option) any later version.
	13	*
	14	* The author(s) of this software shall not be held liable for damages
	15	* of any nature resulting due to the use of this software. This
	16	* software is provided AS-IS with no warranties.
32ee8c3e	17	*
1da177e4 LT	18	* Date Errata Description
	19	* 20020525 N44, O17 12.5% or 25% DC causes lockup
	20	*
	21	*/
	22
1da177e4	23	#include <linux/kernel.h>
32ee8c3e	24	#include <linux/module.h>
1da177e4 LT	25	#include <linux/init.h>
	26	#include <linux/smp.h>
	27	#include <linux/cpufreq.h>
1da177e4	28	#include <linux/cpumask.h>
bbfebd66	29	#include <linux/timex.h>
1da177e4	30
32ee8c3e	31	#include <asm/processor.h>
1da177e4	32	#include <asm/msr.h>
199785ea	33	#include <asm/timer.h>
1da177e4 LT	34
	35	#include "speedstep-lib.h"
	36
	37	#define PFX "p4-clockmod: "
bbfebd66 DJ	38	#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, \
bbfebd66 DJ	39	"p4-clockmod", msg)
1da177e4 LT	40
	41	/*
	42	* Duty Cycle (3bits), note DC_DISABLE is not specified in
	43	* intel docs i just use it to mean disable
	44	*/
	45	enum {
	46	DC_RESV, DC_DFLT, DC_25PT, DC_38PT, DC_50PT,
	47	DC_64PT, DC_75PT, DC_88PT, DC_DISABLE
	48	};
	49
	50	#define DC_ENTRIES 8
	51
	52
	53	static int has_N44_O17_errata[NR_CPUS];
	54	static unsigned int stock_freq;
	55	static struct cpufreq_driver p4clockmod_driver;
	56	static unsigned int cpufreq_p4_get(unsigned int cpu);
	57
	58	static int cpufreq_p4_setdc(unsigned int cpu, unsigned int newstate)
	59	{
	60	u32 l, h;
	61
bbfebd66 DJ	62	if (!cpu_online(cpu) \|\|
bbfebd66 DJ	63	(newstate > DC_DISABLE) \|\| (newstate == DC_RESV))
1da177e4 LT	64	return -EINVAL;
1da177e4 LT	65
551948bc	66	rdmsr_on_cpu(cpu, MSR_IA32_THERM_STATUS, &l, &h);
1da177e4 LT	67
	68	if (l & 0x01)
	69	dprintk("CPU#%d currently thermal throttled\n", cpu);
	70
bbfebd66 DJ	71	if (has_N44_O17_errata[cpu] &&
bbfebd66 DJ	72	(newstate == DC_25PT \|\| newstate == DC_DFLT))
1da177e4 LT	73	newstate = DC_38PT;
1da177e4 LT	74
551948bc	75	rdmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, &l, &h);
1da177e4 LT	76	if (newstate == DC_DISABLE) {
1da177e4 LT	77	dprintk("CPU#%d disabling modulation\n", cpu);
551948bc	78	wrmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, l & ~(1<<4), h);
1da177e4 LT	79	} else {
	80	dprintk("CPU#%d setting duty cycle to %d%%\n",
	81	cpu, ((125 * newstate) / 10));
32ee8c3e	82	/* bits 63 - 5 : reserved
1da177e4 LT	83	* bit 4 : enable/disable
	84	* bits 3-1 : duty cycle
	85	* bit 0 : reserved
	86	*/
	87	l = (l & ~14);
	88	l = l \| (1<<4) \| ((newstate & 0x7)<<1);
551948bc	89	wrmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, l, h);
1da177e4 LT	90	}
	91
	92	return 0;
	93	}
	94
	95
	96	static struct cpufreq_frequency_table p4clockmod_table[] = {
	97	{DC_RESV, CPUFREQ_ENTRY_INVALID},
	98	{DC_DFLT, 0},
	99	{DC_25PT, 0},
	100	{DC_38PT, 0},
	101	{DC_50PT, 0},
	102	{DC_64PT, 0},
	103	{DC_75PT, 0},
	104	{DC_88PT, 0},
	105	{DC_DISABLE, 0},
	106	{DC_RESV, CPUFREQ_TABLE_END},
	107	};
	108
	109
	110	static int cpufreq_p4_target(struct cpufreq_policy *policy,
	111	unsigned int target_freq,
	112	unsigned int relation)
	113	{
	114	unsigned int newstate = DC_RESV;
	115	struct cpufreq_freqs freqs;
1da177e4 LT	116	int i;
1da177e4 LT	117
bbfebd66 DJ	118	if (cpufreq_frequency_table_target(policy, &p4clockmod_table[0],
bbfebd66 DJ	119	target_freq, relation, &newstate))
1da177e4 LT	120	return -EINVAL;
	121
	122	freqs.old = cpufreq_p4_get(policy->cpu);
	123	freqs.new = stock_freq * p4clockmod_table[newstate].index / 8;
	124
	125	if (freqs.new == freqs.old)
	126	return 0;
	127
	128	/* notifiers */
835481d9	129	for_each_cpu(i, policy->cpus) {
1da177e4 LT	130	freqs.cpu = i;
	131	cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
	132	}
	133
bbfebd66 DJ	134	/* run on each logical CPU,
bbfebd66 DJ	135	* see section 13.15.3 of IA32 Intel Architecture Software
32ee8c3e	136	* Developer's Manual, Volume 3
1da177e4	137	*/
835481d9	138	for_each_cpu(i, policy->cpus)
1da177e4	139	cpufreq_p4_setdc(i, p4clockmod_table[newstate].index);
1da177e4 LT	140
1da177e4 LT	141	/* notifiers */
835481d9	142	for_each_cpu(i, policy->cpus) {
1da177e4 LT	143	freqs.cpu = i;
	144	cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
	145	}
	146
	147	return 0;
	148	}
	149
	150
	151	static int cpufreq_p4_verify(struct cpufreq_policy *policy)
	152	{
	153	return cpufreq_frequency_table_verify(policy, &p4clockmod_table[0]);
	154	}
	155
	156
	157	static unsigned int cpufreq_p4_get_frequency(struct cpuinfo_x86 *c)
	158	{
4e74663c DB	159	if (c->x86 == 0x06) {
4e74663c DB	160	if (cpu_has(c, X86_FEATURE_EST))
853cee26 NC	161	printk_once(KERN_WARNING PFX "Warning: EST-capable "
	162	"CPU detected. The acpi-cpufreq module offers "
	163	"voltage scaling in addition to frequency "
bbfebd66 DJ	164	"scaling. You should use that instead of "
bbfebd66 DJ	165	"p4-clockmod, if possible.\n");
4e74663c DB	166	switch (c->x86_model) {
	167	case 0x0E: /* Core */
	168	case 0x0F: /* Core Duo */
8529154e	169	case 0x16: /* Celeron Core */
43195037	170	case 0x1C: /* Atom */
4e74663c	171	p4clockmod_driver.flags \|= CPUFREQ_CONST_LOOPS;
bbfebd66	172	return speedstep_get_frequency(SPEEDSTEP_CPU_PCORE);
4e74663c DB	173	case 0x0D: /* Pentium M (Dothan) */
	174	p4clockmod_driver.flags \|= CPUFREQ_CONST_LOOPS;
	175	/* fall through */
	176	case 0x09: /* Pentium M (Banias) */
bbfebd66	177	return speedstep_get_frequency(SPEEDSTEP_CPU_PM);
4e74663c	178	}
1da177e4 LT	179	}
1da177e4 LT	180
9d1f44ee	181	if (c->x86 != 0xF)
1da177e4	182	return 0;
1da177e4 LT	183
	184	/* on P-4s, the TSC runs with constant frequency independent whether
	185	* throttling is active or not. */
	186	p4clockmod_driver.flags \|= CPUFREQ_CONST_LOOPS;
	187
bbfebd66	188	if (speedstep_detect_processor() == SPEEDSTEP_CPU_P4M) {
1da177e4 LT	189	printk(KERN_WARNING PFX "Warning: Pentium 4-M detected. "
	190	"The speedstep-ich or acpi cpufreq modules offer "
	191	"voltage scaling in addition of frequency scaling. "
	192	"You should use either one instead of p4-clockmod, "
	193	"if possible.\n");
bbfebd66	194	return speedstep_get_frequency(SPEEDSTEP_CPU_P4M);
1da177e4 LT	195	}
1da177e4 LT	196
bbfebd66	197	return speedstep_get_frequency(SPEEDSTEP_CPU_P4D);
1da177e4 LT	198	}
1da177e4 LT	199
32ee8c3e	200
1da177e4 LT	201
	202	static int cpufreq_p4_cpu_init(struct cpufreq_policy *policy)
	203	{
92cb7612	204	struct cpuinfo_x86 *c = &cpu_data(policy->cpu);
1da177e4 LT	205	int cpuid = 0;
	206	unsigned int i;
	207
	208	#ifdef CONFIG_SMP
7ad728f9	209	cpumask_copy(policy->cpus, cpu_sibling_mask(policy->cpu));
1da177e4 LT	210	#endif
	211
	212	/* Errata workaround */
	213	cpuid = (c->x86 << 8) \| (c->x86_model << 4) \| c->x86_mask;
	214	switch (cpuid) {
	215	case 0x0f07:
	216	case 0x0f0a:
	217	case 0x0f11:
	218	case 0x0f12:
	219	has_N44_O17_errata[policy->cpu] = 1;
	220	dprintk("has errata -- disabling low frequencies\n");
	221	}
32ee8c3e	222
199785ea MCO	223	if (speedstep_detect_processor() == SPEEDSTEP_CPU_P4D &&
	224	c->x86_model < 2) {
	225	/* switch to maximum frequency and measure result */
	226	cpufreq_p4_setdc(policy->cpu, DC_DISABLE);
	227	recalibrate_cpu_khz();
	228	}
1da177e4 LT	229	/* get max frequency */
	230	stock_freq = cpufreq_p4_get_frequency(c);
	231	if (!stock_freq)
	232	return -EINVAL;
	233
	234	/* table init */
bbfebd66 DJ	235	for (i = 1; (p4clockmod_table[i].frequency != CPUFREQ_TABLE_END); i++) {
bbfebd66 DJ	236	if ((i < 2) && (has_N44_O17_errata[policy->cpu]))
1da177e4 LT	237	p4clockmod_table[i].frequency = CPUFREQ_ENTRY_INVALID;
	238	else
	239	p4clockmod_table[i].frequency = (stock_freq * i)/8;
	240	}
	241	cpufreq_frequency_table_get_attr(p4clockmod_table, policy->cpu);
32ee8c3e	242
1da177e4	243	/* cpuinfo and default policy values */
36e8abf3 DJ	244
	245	/* the transition latency is set to be 1 higher than the maximum
	246	* transition latency of the ondemand governor */
	247	policy->cpuinfo.transition_latency = 10000001;
1da177e4 LT	248	policy->cur = stock_freq;
	249
	250	return cpufreq_frequency_table_cpuinfo(policy, &p4clockmod_table[0]);
	251	}
	252
	253
	254	static int cpufreq_p4_cpu_exit(struct cpufreq_policy *policy)
	255	{
32ee8c3e	256	cpufreq_frequency_table_put_attr(policy->cpu);
1da177e4 LT	257	return 0;
	258	}
	259
	260	static unsigned int cpufreq_p4_get(unsigned int cpu)
	261	{
1da177e4 LT	262	u32 l, h;
1da177e4 LT	263
551948bc	264	rdmsr_on_cpu(cpu, MSR_IA32_THERM_CONTROL, &l, &h);
1da177e4 LT	265
	266	if (l & 0x10) {
	267	l = l >> 1;
	268	l &= 0x7;
	269	} else
	270	l = DC_DISABLE;
	271
	272	if (l != DC_DISABLE)
bbfebd66	273	return stock_freq * l / 8;
1da177e4 LT	274
	275	return stock_freq;
	276	}
	277
bbfebd66	278	static struct freq_attr *p4clockmod_attr[] = {
1da177e4 LT	279	&cpufreq_freq_attr_scaling_available_freqs,
	280	NULL,
	281	};
	282
	283	static struct cpufreq_driver p4clockmod_driver = {
32ee8c3e	284	.verify = cpufreq_p4_verify,
1da177e4 LT	285	.target = cpufreq_p4_target,
	286	.init = cpufreq_p4_cpu_init,
	287	.exit = cpufreq_p4_cpu_exit,
	288	.get = cpufreq_p4_get,
	289	.name = "p4-clockmod",
	290	.owner = THIS_MODULE,
	291	.attr = p4clockmod_attr,
	292	};
	293
	294
	295	static int __init cpufreq_p4_init(void)
32ee8c3e	296	{
92cb7612	297	struct cpuinfo_x86 *c = &cpu_data(0);
1da177e4 LT	298	int ret;
	299
	300	/*
32ee8c3e	301	* THERM_CONTROL is architectural for IA32 now, so
1da177e4 LT	302	* we can rely on the capability checks
	303	*/
	304	if (c->x86_vendor != X86_VENDOR_INTEL)
	305	return -ENODEV;
	306
8ce116e5 IM	307	if (!test_cpu_cap(c, X86_FEATURE_ACPI) \|\|
8ce116e5 IM	308	!test_cpu_cap(c, X86_FEATURE_ACC))
1da177e4 LT	309	return -ENODEV;
	310
	311	ret = cpufreq_register_driver(&p4clockmod_driver);
	312	if (!ret)
bbfebd66 DJ	313	printk(KERN_INFO PFX "P4/Xeon(TM) CPU On-Demand Clock "
bbfebd66 DJ	314	"Modulation available\n");
1da177e4	315
bbfebd66	316	return ret;
1da177e4 LT	317	}
	318
	319
	320	static void __exit cpufreq_p4_exit(void)
	321	{
	322	cpufreq_unregister_driver(&p4clockmod_driver);
	323	}
	324
	325
bbfebd66 DJ	326	MODULE_AUTHOR("Zwane Mwaikambo <zwane@commfireservices.com>");
	327	MODULE_DESCRIPTION("cpufreq driver for Pentium(TM) 4/Xeon(TM)");
	328	MODULE_LICENSE("GPL");
1da177e4 LT	329
	330	late_initcall(cpufreq_p4_init);
	331	module_exit(cpufreq_p4_exit);