1/*
2 *  Copyright (C) 2002 - 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
3 *  and                       Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * This driver adds basic cpufreq support for SMU & 970FX based G5 Macs,
10 * that is iMac G5 and latest single CPU desktop.
11 */
12
13#undef DEBUG
14
15#include <linux/module.h>
16#include <linux/types.h>
17#include <linux/errno.h>
18#include <linux/kernel.h>
19#include <linux/delay.h>
20#include <linux/sched.h>
21#include <linux/cpufreq.h>
22#include <linux/init.h>
23#include <linux/completion.h>
24#include <linux/mutex.h>
25#include <linux/of_device.h>
26#include <asm/prom.h>
27#include <asm/machdep.h>
28#include <asm/irq.h>
29#include <asm/sections.h>
30#include <asm/cputable.h>
31#include <asm/time.h>
32#include <asm/smu.h>
33#include <asm/pmac_pfunc.h>
34
35#define DBG(fmt...) pr_debug(fmt)
36
37/* see 970FX user manual */
38
39#define SCOM_PCR 0x0aa001			/* PCR scom addr */
40
41#define PCR_HILO_SELECT		0x80000000U	/* 1 = PCR, 0 = PCRH */
42#define PCR_SPEED_FULL		0x00000000U	/* 1:1 speed value */
43#define PCR_SPEED_HALF		0x00020000U	/* 1:2 speed value */
44#define PCR_SPEED_QUARTER	0x00040000U	/* 1:4 speed value */
45#define PCR_SPEED_MASK		0x000e0000U	/* speed mask */
46#define PCR_SPEED_SHIFT		17
47#define PCR_FREQ_REQ_VALID	0x00010000U	/* freq request valid */
48#define PCR_VOLT_REQ_VALID	0x00008000U	/* volt request valid */
49#define PCR_TARGET_TIME_MASK	0x00006000U	/* target time */
50#define PCR_STATLAT_MASK	0x00001f00U	/* STATLAT value */
51#define PCR_SNOOPLAT_MASK	0x000000f0U	/* SNOOPLAT value */
52#define PCR_SNOOPACC_MASK	0x0000000fU	/* SNOOPACC value */
53
54#define SCOM_PSR 0x408001			/* PSR scom addr */
55/* warning: PSR is a 64 bits register */
56#define PSR_CMD_RECEIVED	0x2000000000000000U   /* command received */
57#define PSR_CMD_COMPLETED	0x1000000000000000U   /* command completed */
58#define PSR_CUR_SPEED_MASK	0x0300000000000000U   /* current speed */
59#define PSR_CUR_SPEED_SHIFT	(56)
60
61/*
62 * The G5 only supports two frequencies (Quarter speed is not supported)
63 */
64#define CPUFREQ_HIGH                  0
65#define CPUFREQ_LOW                   1
66
67static struct cpufreq_frequency_table g5_cpu_freqs[] = {
68	{0, CPUFREQ_HIGH,	0},
69	{0, CPUFREQ_LOW,	0},
70	{0, 0,			CPUFREQ_TABLE_END},
71};
72
73/* Power mode data is an array of the 32 bits PCR values to use for
74 * the various frequencies, retrieved from the device-tree
75 */
76static int g5_pmode_cur;
77
78static void (*g5_switch_volt)(int speed_mode);
79static int (*g5_switch_freq)(int speed_mode);
80static int (*g5_query_freq)(void);
81
82static unsigned long transition_latency;
83
84#ifdef CONFIG_PMAC_SMU
85
86static const u32 *g5_pmode_data;
87static int g5_pmode_max;
88
89static struct smu_sdbp_fvt *g5_fvt_table;	/* table of op. points */
90static int g5_fvt_count;			/* number of op. points */
91static int g5_fvt_cur;				/* current op. point */
92
93/*
94 * SMU based voltage switching for Neo2 platforms
95 */
96
97static void g5_smu_switch_volt(int speed_mode)
98{
99	struct smu_simple_cmd	cmd;
100
101	DECLARE_COMPLETION_ONSTACK(comp);
102	smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, smu_done_complete,
103			 &comp, 'V', 'S', 'L', 'E', 'W',
104			 0xff, g5_fvt_cur+1, speed_mode);
105	wait_for_completion(&comp);
106}
107
108/*
109 * Platform function based voltage/vdnap switching for Neo2
110 */
111
112static struct pmf_function *pfunc_set_vdnap0;
113static struct pmf_function *pfunc_vdnap0_complete;
114
115static void g5_vdnap_switch_volt(int speed_mode)
116{
117	struct pmf_args args;
118	u32 slew, done = 0;
119	unsigned long timeout;
120
121	slew = (speed_mode == CPUFREQ_LOW) ? 1 : 0;
122	args.count = 1;
123	args.u[0].p = &slew;
124
125	pmf_call_one(pfunc_set_vdnap0, &args);
126
127	/* It's an irq GPIO so we should be able to just block here,
128	 * I'll do that later after I've properly tested the IRQ code for
129	 * platform functions
130	 */
131	timeout = jiffies + HZ/10;
132	while(!time_after(jiffies, timeout)) {
133		args.count = 1;
134		args.u[0].p = &done;
135		pmf_call_one(pfunc_vdnap0_complete, &args);
136		if (done)
137			break;
138		usleep_range(1000, 1000);
139	}
140	if (done == 0)
141		printk(KERN_WARNING "cpufreq: Timeout in clock slewing !\n");
142}
143
144
145/*
146 * SCOM based frequency switching for 970FX rev3
147 */
148static int g5_scom_switch_freq(int speed_mode)
149{
150	unsigned long flags;
151	int to;
152
153	/* If frequency is going up, first ramp up the voltage */
154	if (speed_mode < g5_pmode_cur)
155		g5_switch_volt(speed_mode);
156
157	local_irq_save(flags);
158
159	/* Clear PCR high */
160	scom970_write(SCOM_PCR, 0);
161	/* Clear PCR low */
162       	scom970_write(SCOM_PCR, PCR_HILO_SELECT | 0);
163	/* Set PCR low */
164	scom970_write(SCOM_PCR, PCR_HILO_SELECT |
165		      g5_pmode_data[speed_mode]);
166
167	/* Wait for completion */
168	for (to = 0; to < 10; to++) {
169		unsigned long psr = scom970_read(SCOM_PSR);
170
171		if ((psr & PSR_CMD_RECEIVED) == 0 &&
172		    (((psr >> PSR_CUR_SPEED_SHIFT) ^
173		      (g5_pmode_data[speed_mode] >> PCR_SPEED_SHIFT)) & 0x3)
174		    == 0)
175			break;
176		if (psr & PSR_CMD_COMPLETED)
177			break;
178		udelay(100);
179	}
180
181	local_irq_restore(flags);
182
183	/* If frequency is going down, last ramp the voltage */
184	if (speed_mode > g5_pmode_cur)
185		g5_switch_volt(speed_mode);
186
187	g5_pmode_cur = speed_mode;
188	ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul;
189
190	return 0;
191}
192
193static int g5_scom_query_freq(void)
194{
195	unsigned long psr = scom970_read(SCOM_PSR);
196	int i;
197
198	for (i = 0; i <= g5_pmode_max; i++)
199		if ((((psr >> PSR_CUR_SPEED_SHIFT) ^
200		      (g5_pmode_data[i] >> PCR_SPEED_SHIFT)) & 0x3) == 0)
201			break;
202	return i;
203}
204
205/*
206 * Fake voltage switching for platforms with missing support
207 */
208
209static void g5_dummy_switch_volt(int speed_mode)
210{
211}
212
213#endif /* CONFIG_PMAC_SMU */
214
215/*
216 * Platform function based voltage switching for PowerMac7,2 & 7,3
217 */
218
219static struct pmf_function *pfunc_cpu0_volt_high;
220static struct pmf_function *pfunc_cpu0_volt_low;
221static struct pmf_function *pfunc_cpu1_volt_high;
222static struct pmf_function *pfunc_cpu1_volt_low;
223
224static void g5_pfunc_switch_volt(int speed_mode)
225{
226	if (speed_mode == CPUFREQ_HIGH) {
227		if (pfunc_cpu0_volt_high)
228			pmf_call_one(pfunc_cpu0_volt_high, NULL);
229		if (pfunc_cpu1_volt_high)
230			pmf_call_one(pfunc_cpu1_volt_high, NULL);
231	} else {
232		if (pfunc_cpu0_volt_low)
233			pmf_call_one(pfunc_cpu0_volt_low, NULL);
234		if (pfunc_cpu1_volt_low)
235			pmf_call_one(pfunc_cpu1_volt_low, NULL);
236	}
237	usleep_range(10000, 10000); /* should be faster , to fix */
238}
239
240/*
241 * Platform function based frequency switching for PowerMac7,2 & 7,3
242 */
243
244static struct pmf_function *pfunc_cpu_setfreq_high;
245static struct pmf_function *pfunc_cpu_setfreq_low;
246static struct pmf_function *pfunc_cpu_getfreq;
247static struct pmf_function *pfunc_slewing_done;
248
249static int g5_pfunc_switch_freq(int speed_mode)
250{
251	struct pmf_args args;
252	u32 done = 0;
253	unsigned long timeout;
254	int rc;
255
256	DBG("g5_pfunc_switch_freq(%d)\n", speed_mode);
257
258	/* If frequency is going up, first ramp up the voltage */
259	if (speed_mode < g5_pmode_cur)
260		g5_switch_volt(speed_mode);
261
262	/* Do it */
263	if (speed_mode == CPUFREQ_HIGH)
264		rc = pmf_call_one(pfunc_cpu_setfreq_high, NULL);
265	else
266		rc = pmf_call_one(pfunc_cpu_setfreq_low, NULL);
267
268	if (rc)
269		printk(KERN_WARNING "cpufreq: pfunc switch error %d\n", rc);
270
271	/* It's an irq GPIO so we should be able to just block here,
272	 * I'll do that later after I've properly tested the IRQ code for
273	 * platform functions
274	 */
275	timeout = jiffies + HZ/10;
276	while(!time_after(jiffies, timeout)) {
277		args.count = 1;
278		args.u[0].p = &done;
279		pmf_call_one(pfunc_slewing_done, &args);
280		if (done)
281			break;
282		usleep_range(500, 500);
283	}
284	if (done == 0)
285		printk(KERN_WARNING "cpufreq: Timeout in clock slewing !\n");
286
287	/* If frequency is going down, last ramp the voltage */
288	if (speed_mode > g5_pmode_cur)
289		g5_switch_volt(speed_mode);
290
291	g5_pmode_cur = speed_mode;
292	ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul;
293
294	return 0;
295}
296
297static int g5_pfunc_query_freq(void)
298{
299	struct pmf_args args;
300	u32 val = 0;
301
302	args.count = 1;
303	args.u[0].p = &val;
304	pmf_call_one(pfunc_cpu_getfreq, &args);
305	return val ? CPUFREQ_HIGH : CPUFREQ_LOW;
306}
307
308
309/*
310 * Common interface to the cpufreq core
311 */
312
313static int g5_cpufreq_target(struct cpufreq_policy *policy, unsigned int index)
314{
315	return g5_switch_freq(index);
316}
317
318static unsigned int g5_cpufreq_get_speed(unsigned int cpu)
319{
320	return g5_cpu_freqs[g5_pmode_cur].frequency;
321}
322
323static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy)
324{
325	return cpufreq_generic_init(policy, g5_cpu_freqs, transition_latency);
326}
327
328static struct cpufreq_driver g5_cpufreq_driver = {
329	.name		= "powermac",
330	.flags		= CPUFREQ_CONST_LOOPS,
331	.init		= g5_cpufreq_cpu_init,
332	.verify		= cpufreq_generic_frequency_table_verify,
333	.target_index	= g5_cpufreq_target,
334	.get		= g5_cpufreq_get_speed,
335	.attr 		= cpufreq_generic_attr,
336};
337
338
339#ifdef CONFIG_PMAC_SMU
340
341static int __init g5_neo2_cpufreq_init(struct device_node *cpunode)
342{
343	unsigned int psize, ssize;
344	unsigned long max_freq;
345	char *freq_method, *volt_method;
346	const u32 *valp;
347	u32 pvr_hi;
348	int use_volts_vdnap = 0;
349	int use_volts_smu = 0;
350	int rc = -ENODEV;
351
352	/* Check supported platforms */
353	if (of_machine_is_compatible("PowerMac8,1") ||
354	    of_machine_is_compatible("PowerMac8,2") ||
355	    of_machine_is_compatible("PowerMac9,1") ||
356	    of_machine_is_compatible("PowerMac12,1"))
357		use_volts_smu = 1;
358	else if (of_machine_is_compatible("PowerMac11,2"))
359		use_volts_vdnap = 1;
360	else
361		return -ENODEV;
362
363	/* Check 970FX for now */
364	valp = of_get_property(cpunode, "cpu-version", NULL);
365	if (!valp) {
366		DBG("No cpu-version property !\n");
367		goto bail_noprops;
368	}
369	pvr_hi = (*valp) >> 16;
370	if (pvr_hi != 0x3c && pvr_hi != 0x44) {
371		printk(KERN_ERR "cpufreq: Unsupported CPU version\n");
372		goto bail_noprops;
373	}
374
375	/* Look for the powertune data in the device-tree */
376	g5_pmode_data = of_get_property(cpunode, "power-mode-data",&psize);
377	if (!g5_pmode_data) {
378		DBG("No power-mode-data !\n");
379		goto bail_noprops;
380	}
381	g5_pmode_max = psize / sizeof(u32) - 1;
382
383	if (use_volts_smu) {
384		const struct smu_sdbp_header *shdr;
385
386		/* Look for the FVT table */
387		shdr = smu_get_sdb_partition(SMU_SDB_FVT_ID, NULL);
388		if (!shdr)
389			goto bail_noprops;
390		g5_fvt_table = (struct smu_sdbp_fvt *)&shdr[1];
391		ssize = (shdr->len * sizeof(u32)) - sizeof(*shdr);
392		g5_fvt_count = ssize / sizeof(*g5_fvt_table);
393		g5_fvt_cur = 0;
394
395		/* Sanity checking */
396		if (g5_fvt_count < 1 || g5_pmode_max < 1)
397			goto bail_noprops;
398
399		g5_switch_volt = g5_smu_switch_volt;
400		volt_method = "SMU";
401	} else if (use_volts_vdnap) {
402		struct device_node *root;
403
404		root = of_find_node_by_path("/");
405		if (root == NULL) {
406			printk(KERN_ERR "cpufreq: Can't find root of "
407			       "device tree\n");
408			goto bail_noprops;
409		}
410		pfunc_set_vdnap0 = pmf_find_function(root, "set-vdnap0");
411		pfunc_vdnap0_complete =
412			pmf_find_function(root, "slewing-done");
413		if (pfunc_set_vdnap0 == NULL ||
414		    pfunc_vdnap0_complete == NULL) {
415			printk(KERN_ERR "cpufreq: Can't find required "
416			       "platform function\n");
417			goto bail_noprops;
418		}
419
420		g5_switch_volt = g5_vdnap_switch_volt;
421		volt_method = "GPIO";
422	} else {
423		g5_switch_volt = g5_dummy_switch_volt;
424		volt_method = "none";
425	}
426
427	/*
428	 * From what I see, clock-frequency is always the maximal frequency.
429	 * The current driver can not slew sysclk yet, so we really only deal
430	 * with powertune steps for now. We also only implement full freq and
431	 * half freq in this version. So far, I haven't yet seen a machine
432	 * supporting anything else.
433	 */
434	valp = of_get_property(cpunode, "clock-frequency", NULL);
435	if (!valp)
436		return -ENODEV;
437	max_freq = (*valp)/1000;
438	g5_cpu_freqs[0].frequency = max_freq;
439	g5_cpu_freqs[1].frequency = max_freq/2;
440
441	/* Set callbacks */
442	transition_latency = 12000;
443	g5_switch_freq = g5_scom_switch_freq;
444	g5_query_freq = g5_scom_query_freq;
445	freq_method = "SCOM";
446
447	/* Force apply current frequency to make sure everything is in
448	 * sync (voltage is right for example). Firmware may leave us with
449	 * a strange setting ...
450	 */
451	g5_switch_volt(CPUFREQ_HIGH);
452	msleep(10);
453	g5_pmode_cur = -1;
454	g5_switch_freq(g5_query_freq());
455
456	printk(KERN_INFO "Registering G5 CPU frequency driver\n");
457	printk(KERN_INFO "Frequency method: %s, Voltage method: %s\n",
458	       freq_method, volt_method);
459	printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
460		g5_cpu_freqs[1].frequency/1000,
461		g5_cpu_freqs[0].frequency/1000,
462		g5_cpu_freqs[g5_pmode_cur].frequency/1000);
463
464	rc = cpufreq_register_driver(&g5_cpufreq_driver);
465
466	/* We keep the CPU node on hold... hopefully, Apple G5 don't have
467	 * hotplug CPU with a dynamic device-tree ...
468	 */
469	return rc;
470
471 bail_noprops:
472	of_node_put(cpunode);
473
474	return rc;
475}
476
477#endif /* CONFIG_PMAC_SMU */
478
479
480static int __init g5_pm72_cpufreq_init(struct device_node *cpunode)
481{
482	struct device_node *cpuid = NULL, *hwclock = NULL;
483	const u8 *eeprom = NULL;
484	const u32 *valp;
485	u64 max_freq, min_freq, ih, il;
486	int has_volt = 1, rc = 0;
487
488	DBG("cpufreq: Initializing for PowerMac7,2, PowerMac7,3 and"
489	    " RackMac3,1...\n");
490
491	/* Lookup the cpuid eeprom node */
492        cpuid = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/cpuid@a0");
493	if (cpuid != NULL)
494		eeprom = of_get_property(cpuid, "cpuid", NULL);
495	if (eeprom == NULL) {
496		printk(KERN_ERR "cpufreq: Can't find cpuid EEPROM !\n");
497		rc = -ENODEV;
498		goto bail;
499	}
500
501	/* Lookup the i2c hwclock */
502	for_each_node_by_name(hwclock, "i2c-hwclock") {
503		const char *loc = of_get_property(hwclock,
504				"hwctrl-location", NULL);
505		if (loc == NULL)
506			continue;
507		if (strcmp(loc, "CPU CLOCK"))
508			continue;
509		if (!of_get_property(hwclock, "platform-get-frequency", NULL))
510			continue;
511		break;
512	}
513	if (hwclock == NULL) {
514		printk(KERN_ERR "cpufreq: Can't find i2c clock chip !\n");
515		rc = -ENODEV;
516		goto bail;
517	}
518
519	DBG("cpufreq: i2c clock chip found: %s\n", hwclock->full_name);
520
521	/* Now get all the platform functions */
522	pfunc_cpu_getfreq =
523		pmf_find_function(hwclock, "get-frequency");
524	pfunc_cpu_setfreq_high =
525		pmf_find_function(hwclock, "set-frequency-high");
526	pfunc_cpu_setfreq_low =
527		pmf_find_function(hwclock, "set-frequency-low");
528	pfunc_slewing_done =
529		pmf_find_function(hwclock, "slewing-done");
530	pfunc_cpu0_volt_high =
531		pmf_find_function(hwclock, "set-voltage-high-0");
532	pfunc_cpu0_volt_low =
533		pmf_find_function(hwclock, "set-voltage-low-0");
534	pfunc_cpu1_volt_high =
535		pmf_find_function(hwclock, "set-voltage-high-1");
536	pfunc_cpu1_volt_low =
537		pmf_find_function(hwclock, "set-voltage-low-1");
538
539	/* Check we have minimum requirements */
540	if (pfunc_cpu_getfreq == NULL || pfunc_cpu_setfreq_high == NULL ||
541	    pfunc_cpu_setfreq_low == NULL || pfunc_slewing_done == NULL) {
542		printk(KERN_ERR "cpufreq: Can't find platform functions !\n");
543		rc = -ENODEV;
544		goto bail;
545	}
546
547	/* Check that we have complete sets */
548	if (pfunc_cpu0_volt_high == NULL || pfunc_cpu0_volt_low == NULL) {
549		pmf_put_function(pfunc_cpu0_volt_high);
550		pmf_put_function(pfunc_cpu0_volt_low);
551		pfunc_cpu0_volt_high = pfunc_cpu0_volt_low = NULL;
552		has_volt = 0;
553	}
554	if (!has_volt ||
555	    pfunc_cpu1_volt_high == NULL || pfunc_cpu1_volt_low == NULL) {
556		pmf_put_function(pfunc_cpu1_volt_high);
557		pmf_put_function(pfunc_cpu1_volt_low);
558		pfunc_cpu1_volt_high = pfunc_cpu1_volt_low = NULL;
559	}
560
561	/* Note: The device tree also contains a "platform-set-values"
562	 * function for which I haven't quite figured out the usage. It
563	 * might have to be called on init and/or wakeup, I'm not too sure
564	 * but things seem to work fine without it so far ...
565	 */
566
567	/* Get max frequency from device-tree */
568	valp = of_get_property(cpunode, "clock-frequency", NULL);
569	if (!valp) {
570		printk(KERN_ERR "cpufreq: Can't find CPU frequency !\n");
571		rc = -ENODEV;
572		goto bail;
573	}
574
575	max_freq = (*valp)/1000;
576
577	/* Now calculate reduced frequency by using the cpuid input freq
578	 * ratio. This requires 64 bits math unless we are willing to lose
579	 * some precision
580	 */
581	ih = *((u32 *)(eeprom + 0x10));
582	il = *((u32 *)(eeprom + 0x20));
583
584	/* Check for machines with no useful settings */
585	if (il == ih) {
586		printk(KERN_WARNING "cpufreq: No low frequency mode available"
587		       " on this model !\n");
588		rc = -ENODEV;
589		goto bail;
590	}
591
592	min_freq = 0;
593	if (ih != 0 && il != 0)
594		min_freq = (max_freq * il) / ih;
595
596	/* Sanity check */
597	if (min_freq >= max_freq || min_freq < 1000) {
598		printk(KERN_ERR "cpufreq: Can't calculate low frequency !\n");
599		rc = -ENXIO;
600		goto bail;
601	}
602	g5_cpu_freqs[0].frequency = max_freq;
603	g5_cpu_freqs[1].frequency = min_freq;
604
605	/* Based on a measurement on Xserve G5, rounded up. */
606	transition_latency = 10 * NSEC_PER_MSEC;
607
608	/* Set callbacks */
609	g5_switch_volt = g5_pfunc_switch_volt;
610	g5_switch_freq = g5_pfunc_switch_freq;
611	g5_query_freq = g5_pfunc_query_freq;
612
613	/* Force apply current frequency to make sure everything is in
614	 * sync (voltage is right for example). Firmware may leave us with
615	 * a strange setting ...
616	 */
617	g5_switch_volt(CPUFREQ_HIGH);
618	msleep(10);
619	g5_pmode_cur = -1;
620	g5_switch_freq(g5_query_freq());
621
622	printk(KERN_INFO "Registering G5 CPU frequency driver\n");
623	printk(KERN_INFO "Frequency method: i2c/pfunc, "
624	       "Voltage method: %s\n", has_volt ? "i2c/pfunc" : "none");
625	printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
626		g5_cpu_freqs[1].frequency/1000,
627		g5_cpu_freqs[0].frequency/1000,
628		g5_cpu_freqs[g5_pmode_cur].frequency/1000);
629
630	rc = cpufreq_register_driver(&g5_cpufreq_driver);
631 bail:
632	if (rc != 0) {
633		pmf_put_function(pfunc_cpu_getfreq);
634		pmf_put_function(pfunc_cpu_setfreq_high);
635		pmf_put_function(pfunc_cpu_setfreq_low);
636		pmf_put_function(pfunc_slewing_done);
637		pmf_put_function(pfunc_cpu0_volt_high);
638		pmf_put_function(pfunc_cpu0_volt_low);
639		pmf_put_function(pfunc_cpu1_volt_high);
640		pmf_put_function(pfunc_cpu1_volt_low);
641	}
642	of_node_put(hwclock);
643	of_node_put(cpuid);
644	of_node_put(cpunode);
645
646	return rc;
647}
648
649static int __init g5_cpufreq_init(void)
650{
651	struct device_node *cpunode;
652	int rc = 0;
653
654	/* Get first CPU node */
655	cpunode = of_cpu_device_node_get(0);
656	if (cpunode == NULL) {
657		pr_err("cpufreq: Can't find any CPU node\n");
658		return -ENODEV;
659	}
660
661	if (of_machine_is_compatible("PowerMac7,2") ||
662	    of_machine_is_compatible("PowerMac7,3") ||
663	    of_machine_is_compatible("RackMac3,1"))
664		rc = g5_pm72_cpufreq_init(cpunode);
665#ifdef CONFIG_PMAC_SMU
666	else
667		rc = g5_neo2_cpufreq_init(cpunode);
668#endif /* CONFIG_PMAC_SMU */
669
670	return rc;
671}
672
673module_init(g5_cpufreq_init);
674
675
676MODULE_LICENSE("GPL");
677