2 * cpufreq driver for Enhanced SpeedStep, as found in Intel's Pentium
3 * M (part of the Centrino chipset).
5 * Despite the "SpeedStep" in the name, this is almost entirely unlike
6 * traditional SpeedStep.
8 * Modelled on speedstep.c
10 * Copyright (C) 2003 Jeremy Fitzhardinge <jeremy@goop.org>
12 * WARNING WARNING WARNING
14 * This driver manipulates the PERF_CTL MSR, which is only somewhat
15 * documented. While it seems to work on my laptop, it has not been
16 * tested anywhere else, and it may not work for you, do strange
17 * things or simply crash.
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/init.h>
23 #include <linux/cpufreq.h>
24 #include <linux/config.h>
25 #include <linux/sched.h> /* current */
26 #include <linux/delay.h>
27 #include <linux/compiler.h>
29 #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
30 #include <linux/acpi.h>
31 #include <acpi/processor.h>
35 #include <asm/processor.h>
36 #include <asm/cpufeature.h>
38 #define PFX "speedstep-centrino: "
39 #define MAINTAINER "Jeremy Fitzhardinge <jeremy@goop.org>"
41 #define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "speedstep-centrino", msg)
46 __u8 x86
; /* CPU family */
47 __u8 x86_model
; /* model */
48 __u8 x86_mask
; /* stepping */
60 static const struct cpu_id cpu_ids
[] = {
61 [CPU_BANIAS
] = { 6, 9, 5 },
62 [CPU_DOTHAN_A1
] = { 6, 13, 1 },
63 [CPU_DOTHAN_A2
] = { 6, 13, 2 },
64 [CPU_DOTHAN_B0
] = { 6, 13, 6 },
65 [CPU_MP4HT_D0
] = {15, 3, 4 },
66 [CPU_MP4HT_E0
] = {15, 4, 1 },
68 #define N_IDS ARRAY_SIZE(cpu_ids)
72 const struct cpu_id
*cpu_id
;
73 const char *model_name
;
74 unsigned max_freq
; /* max clock in kHz */
76 struct cpufreq_frequency_table
*op_points
; /* clock/voltage pairs */
78 static int centrino_verify_cpu_id(const struct cpuinfo_x86
*c
, const struct cpu_id
*x
);
80 /* Operating points for current CPU */
81 static struct cpu_model
*centrino_model
[NR_CPUS
];
82 static const struct cpu_id
*centrino_cpu
[NR_CPUS
];
84 static struct cpufreq_driver centrino_driver
;
86 #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE
88 /* Computes the correct form for IA32_PERF_CTL MSR for a particular
89 frequency/voltage operating point; frequency in MHz, volts in mV.
90 This is stored as "index" in the structure. */
93 .frequency = (mhz) * 1000, \
94 .index = (((mhz)/100) << 8) | ((mv - 700) / 16) \
98 * These voltage tables were derived from the Intel Pentium M
99 * datasheet, document 25261202.pdf, Table 5. I have verified they
100 * are consistent with my IBM ThinkPad X31, which has a 1.3GHz Pentium
104 /* Ultra Low Voltage Intel Pentium M processor 900MHz (Banias) */
105 static struct cpufreq_frequency_table banias_900
[] =
110 { .frequency
= CPUFREQ_TABLE_END
}
113 /* Ultra Low Voltage Intel Pentium M processor 1000MHz (Banias) */
114 static struct cpufreq_frequency_table banias_1000
[] =
120 { .frequency
= CPUFREQ_TABLE_END
}
123 /* Low Voltage Intel Pentium M processor 1.10GHz (Banias) */
124 static struct cpufreq_frequency_table banias_1100
[] =
131 { .frequency
= CPUFREQ_TABLE_END
}
135 /* Low Voltage Intel Pentium M processor 1.20GHz (Banias) */
136 static struct cpufreq_frequency_table banias_1200
[] =
144 { .frequency
= CPUFREQ_TABLE_END
}
147 /* Intel Pentium M processor 1.30GHz (Banias) */
148 static struct cpufreq_frequency_table banias_1300
[] =
155 { .frequency
= CPUFREQ_TABLE_END
}
158 /* Intel Pentium M processor 1.40GHz (Banias) */
159 static struct cpufreq_frequency_table banias_1400
[] =
166 { .frequency
= CPUFREQ_TABLE_END
}
169 /* Intel Pentium M processor 1.50GHz (Banias) */
170 static struct cpufreq_frequency_table banias_1500
[] =
178 { .frequency
= CPUFREQ_TABLE_END
}
181 /* Intel Pentium M processor 1.60GHz (Banias) */
182 static struct cpufreq_frequency_table banias_1600
[] =
190 { .frequency
= CPUFREQ_TABLE_END
}
193 /* Intel Pentium M processor 1.70GHz (Banias) */
194 static struct cpufreq_frequency_table banias_1700
[] =
202 { .frequency
= CPUFREQ_TABLE_END
}
206 #define _BANIAS(cpuid, max, name) \
208 .model_name = "Intel(R) Pentium(R) M processor " name "MHz", \
209 .max_freq = (max)*1000, \
210 .op_points = banias_##max, \
212 #define BANIAS(max) _BANIAS(&cpu_ids[CPU_BANIAS], max, #max)
214 /* CPU models, their operating frequency range, and freq/voltage
216 static struct cpu_model models
[] =
218 _BANIAS(&cpu_ids
[CPU_BANIAS
], 900, " 900"),
228 /* NULL model_name is a wildcard */
229 { &cpu_ids
[CPU_DOTHAN_A1
], NULL
, 0, NULL
},
230 { &cpu_ids
[CPU_DOTHAN_A2
], NULL
, 0, NULL
},
231 { &cpu_ids
[CPU_DOTHAN_B0
], NULL
, 0, NULL
},
232 { &cpu_ids
[CPU_MP4HT_D0
], NULL
, 0, NULL
},
233 { &cpu_ids
[CPU_MP4HT_E0
], NULL
, 0, NULL
},
240 static int centrino_cpu_init_table(struct cpufreq_policy
*policy
)
242 struct cpuinfo_x86
*cpu
= &cpu_data
[policy
->cpu
];
243 struct cpu_model
*model
;
245 for(model
= models
; model
->cpu_id
!= NULL
; model
++)
246 if (centrino_verify_cpu_id(cpu
, model
->cpu_id
) &&
247 (model
->model_name
== NULL
||
248 strcmp(cpu
->x86_model_id
, model
->model_name
) == 0))
251 if (model
->cpu_id
== NULL
) {
252 /* No match at all */
253 dprintk(KERN_INFO PFX
"no support for CPU model \"%s\": "
254 "send /proc/cpuinfo to " MAINTAINER
"\n",
259 if (model
->op_points
== NULL
) {
260 /* Matched a non-match */
261 dprintk(KERN_INFO PFX
"no table support for CPU model \"%s\"\n",
263 #ifndef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
264 dprintk(KERN_INFO PFX
"try compiling with CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI enabled\n");
269 centrino_model
[policy
->cpu
] = model
;
271 dprintk("found \"%s\": max frequency: %dkHz\n",
272 model
->model_name
, model
->max_freq
);
278 static inline int centrino_cpu_init_table(struct cpufreq_policy
*policy
) { return -ENODEV
; }
279 #endif /* CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE */
281 static int centrino_verify_cpu_id(const struct cpuinfo_x86
*c
, const struct cpu_id
*x
)
283 if ((c
->x86
== x
->x86
) &&
284 (c
->x86_model
== x
->x86_model
) &&
285 (c
->x86_mask
== x
->x86_mask
))
290 /* To be called only after centrino_model is initialized */
291 static unsigned extract_clock(unsigned msr
, unsigned int cpu
, int failsafe
)
296 * Extract clock in kHz from PERF_CTL value
297 * for centrino, as some DSDTs are buggy.
298 * Ideally, this can be done using the acpi_data structure.
300 if ((centrino_cpu
[cpu
] == &cpu_ids
[CPU_BANIAS
]) ||
301 (centrino_cpu
[cpu
] == &cpu_ids
[CPU_DOTHAN_A1
]) ||
302 (centrino_cpu
[cpu
] == &cpu_ids
[CPU_DOTHAN_B0
])) {
303 msr
= (msr
>> 8) & 0xff;
307 if ((!centrino_model
[cpu
]) || (!centrino_model
[cpu
]->op_points
))
311 for (i
=0;centrino_model
[cpu
]->op_points
[i
].frequency
!= CPUFREQ_TABLE_END
; i
++) {
312 if (msr
== centrino_model
[cpu
]->op_points
[i
].index
)
313 return centrino_model
[cpu
]->op_points
[i
].frequency
;
316 return centrino_model
[cpu
]->op_points
[i
-1].frequency
;
321 /* Return the current CPU frequency in kHz */
322 static unsigned int get_cur_freq(unsigned int cpu
)
326 cpumask_t saved_mask
;
328 saved_mask
= current
->cpus_allowed
;
329 set_cpus_allowed(current
, cpumask_of_cpu(cpu
));
330 if (smp_processor_id() != cpu
)
333 rdmsr(MSR_IA32_PERF_STATUS
, l
, h
);
334 clock_freq
= extract_clock(l
, cpu
, 0);
336 if (unlikely(clock_freq
== 0)) {
338 * On some CPUs, we can see transient MSR values (which are
339 * not present in _PSS), while CPU is doing some automatic
340 * P-state transition (like TM2). Get the last freq set
343 rdmsr(MSR_IA32_PERF_CTL
, l
, h
);
344 clock_freq
= extract_clock(l
, cpu
, 1);
347 set_cpus_allowed(current
, saved_mask
);
352 #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
354 static struct acpi_processor_performance
*acpi_perf_data
[NR_CPUS
];
357 * centrino_cpu_early_init_acpi - Do the preregistering with ACPI P-States
360 * Before doing the actual init, we need to do _PSD related setup whenever
361 * supported by the BIOS. These are handled by this early_init routine.
363 static int centrino_cpu_early_init_acpi(void)
366 struct acpi_processor_performance
*data
;
369 data
= kzalloc(sizeof(struct acpi_processor_performance
),
373 kfree(acpi_perf_data
[j
]);
374 acpi_perf_data
[j
] = NULL
;
378 acpi_perf_data
[i
] = data
;
381 acpi_processor_preregister_performance(acpi_perf_data
);
386 * centrino_cpu_init_acpi - register with ACPI P-States library
388 * Register with the ACPI P-States library (part of drivers/acpi/processor.c)
389 * in order to determine correct frequency and voltage pairings by reading
390 * the _PSS of the ACPI DSDT or SSDT tables.
392 static int centrino_cpu_init_acpi(struct cpufreq_policy
*policy
)
394 unsigned long cur_freq
;
396 unsigned int cpu
= policy
->cpu
;
397 struct acpi_processor_performance
*p
;
399 p
= acpi_perf_data
[cpu
];
401 /* register with ACPI core */
402 if (acpi_processor_register_performance(p
, cpu
)) {
403 dprintk(KERN_INFO PFX
"obtaining ACPI data failed\n");
406 policy
->cpus
= p
->shared_cpu_map
;
407 policy
->shared_type
= p
->shared_type
;
409 /* verify the acpi_data */
410 if (p
->state_count
<= 1) {
411 dprintk("No P-States\n");
416 if ((p
->control_register
.space_id
!= ACPI_ADR_SPACE_FIXED_HARDWARE
) ||
417 (p
->status_register
.space_id
!= ACPI_ADR_SPACE_FIXED_HARDWARE
)) {
418 dprintk("Invalid control/status registers (%x - %x)\n",
419 p
->control_register
.space_id
, p
->status_register
.space_id
);
424 for (i
=0; i
<p
->state_count
; i
++) {
425 if (p
->states
[i
].control
!= p
->states
[i
].status
) {
426 dprintk("Different control (%llu) and status values (%llu)\n",
427 p
->states
[i
].control
, p
->states
[i
].status
);
432 if (!p
->states
[i
].core_frequency
) {
433 dprintk("Zero core frequency for state %u\n", i
);
438 if (p
->states
[i
].core_frequency
> p
->states
[0].core_frequency
) {
439 dprintk("P%u has larger frequency (%llu) than P0 (%llu), skipping\n", i
,
440 p
->states
[i
].core_frequency
, p
->states
[0].core_frequency
);
441 p
->states
[i
].core_frequency
= 0;
446 centrino_model
[cpu
] = kzalloc(sizeof(struct cpu_model
), GFP_KERNEL
);
447 if (!centrino_model
[cpu
]) {
452 centrino_model
[cpu
]->model_name
=NULL
;
453 centrino_model
[cpu
]->max_freq
= p
->states
[0].core_frequency
* 1000;
454 centrino_model
[cpu
]->op_points
= kmalloc(sizeof(struct cpufreq_frequency_table
) *
455 (p
->state_count
+ 1), GFP_KERNEL
);
456 if (!centrino_model
[cpu
]->op_points
) {
461 for (i
=0; i
<p
->state_count
; i
++) {
462 centrino_model
[cpu
]->op_points
[i
].index
= p
->states
[i
].control
;
463 centrino_model
[cpu
]->op_points
[i
].frequency
= p
->states
[i
].core_frequency
* 1000;
464 dprintk("adding state %i with frequency %u and control value %04x\n",
465 i
, centrino_model
[cpu
]->op_points
[i
].frequency
, centrino_model
[cpu
]->op_points
[i
].index
);
467 centrino_model
[cpu
]->op_points
[p
->state_count
].frequency
= CPUFREQ_TABLE_END
;
469 cur_freq
= get_cur_freq(cpu
);
471 for (i
=0; i
<p
->state_count
; i
++) {
472 if (!p
->states
[i
].core_frequency
) {
473 dprintk("skipping state %u\n", i
);
474 centrino_model
[cpu
]->op_points
[i
].frequency
= CPUFREQ_ENTRY_INVALID
;
478 if (extract_clock(centrino_model
[cpu
]->op_points
[i
].index
, cpu
, 0) !=
479 (centrino_model
[cpu
]->op_points
[i
].frequency
)) {
480 dprintk("Invalid encoded frequency (%u vs. %u)\n",
481 extract_clock(centrino_model
[cpu
]->op_points
[i
].index
, cpu
, 0),
482 centrino_model
[cpu
]->op_points
[i
].frequency
);
487 if (cur_freq
== centrino_model
[cpu
]->op_points
[i
].frequency
)
491 /* notify BIOS that we exist */
492 acpi_processor_notify_smm(THIS_MODULE
);
497 kfree(centrino_model
[cpu
]->op_points
);
499 kfree(centrino_model
[cpu
]);
501 acpi_processor_unregister_performance(p
, cpu
);
502 dprintk(KERN_INFO PFX
"invalid ACPI data\n");
506 static inline int centrino_cpu_init_acpi(struct cpufreq_policy
*policy
) { return -ENODEV
; }
507 static inline int centrino_cpu_early_init_acpi(void) { return 0; }
510 static int centrino_cpu_init(struct cpufreq_policy
*policy
)
512 struct cpuinfo_x86
*cpu
= &cpu_data
[policy
->cpu
];
518 /* Only Intel makes Enhanced Speedstep-capable CPUs */
519 if (cpu
->x86_vendor
!= X86_VENDOR_INTEL
|| !cpu_has(cpu
, X86_FEATURE_EST
))
522 if (cpu_has(cpu
, X86_FEATURE_CONSTANT_TSC
))
523 centrino_driver
.flags
|= CPUFREQ_CONST_LOOPS
;
525 if (centrino_cpu_init_acpi(policy
)) {
526 if (policy
->cpu
!= 0)
529 for (i
= 0; i
< N_IDS
; i
++)
530 if (centrino_verify_cpu_id(cpu
, &cpu_ids
[i
]))
534 centrino_cpu
[policy
->cpu
] = &cpu_ids
[i
];
536 if (!centrino_cpu
[policy
->cpu
]) {
537 dprintk(KERN_INFO PFX
"found unsupported CPU with "
538 "Enhanced SpeedStep: send /proc/cpuinfo to "
543 if (centrino_cpu_init_table(policy
)) {
548 /* Check to see if Enhanced SpeedStep is enabled, and try to
550 rdmsr(MSR_IA32_MISC_ENABLE
, l
, h
);
552 if (!(l
& (1<<16))) {
554 dprintk("trying to enable Enhanced SpeedStep (%x)\n", l
);
555 wrmsr(MSR_IA32_MISC_ENABLE
, l
, h
);
557 /* check to see if it stuck */
558 rdmsr(MSR_IA32_MISC_ENABLE
, l
, h
);
559 if (!(l
& (1<<16))) {
560 printk(KERN_INFO PFX
"couldn't enable Enhanced SpeedStep\n");
565 freq
= get_cur_freq(policy
->cpu
);
567 policy
->governor
= CPUFREQ_DEFAULT_GOVERNOR
;
568 policy
->cpuinfo
.transition_latency
= 10000; /* 10uS transition latency */
571 dprintk("centrino_cpu_init: cur=%dkHz\n", policy
->cur
);
573 ret
= cpufreq_frequency_table_cpuinfo(policy
, centrino_model
[policy
->cpu
]->op_points
);
577 cpufreq_frequency_table_get_attr(centrino_model
[policy
->cpu
]->op_points
, policy
->cpu
);
582 static int centrino_cpu_exit(struct cpufreq_policy
*policy
)
584 unsigned int cpu
= policy
->cpu
;
586 if (!centrino_model
[cpu
])
589 cpufreq_frequency_table_put_attr(cpu
);
591 #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
592 if (!centrino_model
[cpu
]->model_name
) {
593 static struct acpi_processor_performance
*p
;
595 if (acpi_perf_data
[cpu
]) {
596 p
= acpi_perf_data
[cpu
];
597 dprintk("unregistering and freeing ACPI data\n");
598 acpi_processor_unregister_performance(p
, cpu
);
599 kfree(centrino_model
[cpu
]->op_points
);
600 kfree(centrino_model
[cpu
]);
605 centrino_model
[cpu
] = NULL
;
611 * centrino_verify - verifies a new CPUFreq policy
612 * @policy: new policy
614 * Limit must be within this model's frequency range at least one
617 static int centrino_verify (struct cpufreq_policy
*policy
)
619 return cpufreq_frequency_table_verify(policy
, centrino_model
[policy
->cpu
]->op_points
);
623 * centrino_setpolicy - set a new CPUFreq policy
624 * @policy: new policy
625 * @target_freq: the target frequency
626 * @relation: how that frequency relates to achieved frequency (CPUFREQ_RELATION_L or CPUFREQ_RELATION_H)
628 * Sets a new CPUFreq policy.
630 static int centrino_target (struct cpufreq_policy
*policy
,
631 unsigned int target_freq
,
632 unsigned int relation
)
634 unsigned int newstate
= 0;
635 unsigned int msr
, oldmsr
= 0, h
= 0, cpu
= policy
->cpu
;
636 struct cpufreq_freqs freqs
;
637 cpumask_t online_policy_cpus
;
638 cpumask_t saved_mask
;
640 cpumask_t covered_cpus
;
642 unsigned int j
, k
, first_cpu
, tmp
;
644 if (unlikely(centrino_model
[cpu
] == NULL
))
647 if (unlikely(cpufreq_frequency_table_target(policy
,
648 centrino_model
[cpu
]->op_points
,
655 #ifdef CONFIG_HOTPLUG_CPU
656 /* cpufreq holds the hotplug lock, so we are safe from here on */
657 cpus_and(online_policy_cpus
, cpu_online_map
, policy
->cpus
);
659 online_policy_cpus
= policy
->cpus
;
662 saved_mask
= current
->cpus_allowed
;
664 cpus_clear(covered_cpus
);
665 for_each_cpu_mask(j
, online_policy_cpus
) {
667 * Support for SMP systems.
668 * Make sure we are running on CPU that wants to change freq
670 cpus_clear(set_mask
);
671 if (policy
->shared_type
== CPUFREQ_SHARED_TYPE_ANY
)
672 cpus_or(set_mask
, set_mask
, online_policy_cpus
);
674 cpu_set(j
, set_mask
);
676 set_cpus_allowed(current
, set_mask
);
677 if (unlikely(!cpu_isset(smp_processor_id(), set_mask
))) {
678 dprintk("couldn't limit to CPUs in this domain\n");
681 /* We haven't started the transition yet. */
687 msr
= centrino_model
[cpu
]->op_points
[newstate
].index
;
690 rdmsr(MSR_IA32_PERF_CTL
, oldmsr
, h
);
691 if (msr
== (oldmsr
& 0xffff)) {
692 dprintk("no change needed - msr was and needs "
693 "to be %x\n", oldmsr
);
698 freqs
.old
= extract_clock(oldmsr
, cpu
, 0);
699 freqs
.new = extract_clock(msr
, cpu
, 0);
701 dprintk("target=%dkHz old=%d new=%d msr=%04x\n",
702 target_freq
, freqs
.old
, freqs
.new, msr
);
704 for_each_cpu_mask(k
, online_policy_cpus
) {
706 cpufreq_notify_transition(&freqs
,
711 /* all but 16 LSB are reserved, treat them with care */
717 wrmsr(MSR_IA32_PERF_CTL
, oldmsr
, h
);
718 if (policy
->shared_type
== CPUFREQ_SHARED_TYPE_ANY
)
721 cpu_set(j
, covered_cpus
);
724 for_each_cpu_mask(k
, online_policy_cpus
) {
726 cpufreq_notify_transition(&freqs
, CPUFREQ_POSTCHANGE
);
729 if (unlikely(retval
)) {
731 * We have failed halfway through the frequency change.
732 * We have sent callbacks to policy->cpus and
733 * MSRs have already been written on coverd_cpus.
737 if (!cpus_empty(covered_cpus
)) {
738 for_each_cpu_mask(j
, covered_cpus
) {
739 set_cpus_allowed(current
, cpumask_of_cpu(j
));
740 wrmsr(MSR_IA32_PERF_CTL
, oldmsr
, h
);
745 freqs
.new = freqs
.old
;
747 for_each_cpu_mask(j
, online_policy_cpus
) {
749 cpufreq_notify_transition(&freqs
, CPUFREQ_PRECHANGE
);
750 cpufreq_notify_transition(&freqs
, CPUFREQ_POSTCHANGE
);
755 set_cpus_allowed(current
, saved_mask
);
759 static struct freq_attr
* centrino_attr
[] = {
760 &cpufreq_freq_attr_scaling_available_freqs
,
764 static struct cpufreq_driver centrino_driver
= {
765 .name
= "centrino", /* should be speedstep-centrino,
766 but there's a 16 char limit */
767 .init
= centrino_cpu_init
,
768 .exit
= centrino_cpu_exit
,
769 .verify
= centrino_verify
,
770 .target
= centrino_target
,
772 .attr
= centrino_attr
,
773 .owner
= THIS_MODULE
,
778 * centrino_init - initializes the Enhanced SpeedStep CPUFreq driver
780 * Initializes the Enhanced SpeedStep support. Returns -ENODEV on
781 * unsupported devices, -ENOENT if there's no voltage table for this
782 * particular CPU model, -EINVAL on problems during initiatization,
783 * and zero on success.
785 * This is quite picky. Not only does the CPU have to advertise the
786 * "est" flag in the cpuid capability flags, we look for a specific
787 * CPU model and stepping, and we need to have the exact model name in
788 * our voltage tables. That is, be paranoid about not releasing
789 * someone's valuable magic smoke.
791 static int __init
centrino_init(void)
793 struct cpuinfo_x86
*cpu
= cpu_data
;
795 if (!cpu_has(cpu
, X86_FEATURE_EST
))
798 centrino_cpu_early_init_acpi();
800 return cpufreq_register_driver(¢rino_driver
);
803 static void __exit
centrino_exit(void)
805 #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
809 cpufreq_unregister_driver(¢rino_driver
);
811 #ifdef CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI
813 kfree(acpi_perf_data
[j
]);
814 acpi_perf_data
[j
] = NULL
;
819 MODULE_AUTHOR ("Jeremy Fitzhardinge <jeremy@goop.org>");
820 MODULE_DESCRIPTION ("Enhanced SpeedStep driver for Intel Pentium M processors.");
821 MODULE_LICENSE ("GPL");
823 late_initcall(centrino_init
);
824 module_exit(centrino_exit
);