1 /*
2  *  Copyright (C) 2002 - 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
3  *  Copyright (C) 2004        John Steele Scott <toojays@toojays.net>
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  * TODO: Need a big cleanup here. Basically, we need to have different
10  * cpufreq_driver structures for the different type of HW instead of the
11  * current mess. We also need to better deal with the detection of the
12  * type of machine.
13  *
14  */
15 
16 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/delay.h>
21 #include <linux/sched.h>
22 #include <linux/adb.h>
23 #include <linux/pmu.h>
24 #include <linux/cpufreq.h>
25 #include <linux/init.h>
26 #include <linux/device.h>
27 #include <linux/hardirq.h>
28 #include <asm/prom.h>
29 #include <asm/machdep.h>
30 #include <asm/irq.h>
31 #include <asm/pmac_feature.h>
32 #include <asm/mmu_context.h>
33 #include <asm/sections.h>
34 #include <asm/cputable.h>
35 #include <asm/time.h>
36 #include <asm/mpic.h>
37 #include <asm/keylargo.h>
38 #include <asm/switch_to.h>
39 
40 /* WARNING !!! This will cause calibrate_delay() to be called,
41  * but this is an __init function ! So you MUST go edit
42  * init/main.c to make it non-init before enabling DEBUG_FREQ
43  */
44 #undef DEBUG_FREQ
45 
46 extern void low_choose_7447a_dfs(int dfs);
47 extern void low_choose_750fx_pll(int pll);
48 extern void low_sleep_handler(void);
49 
50 /*
51  * Currently, PowerMac cpufreq supports only high & low frequencies
52  * that are set by the firmware
53  */
54 static unsigned int low_freq;
55 static unsigned int hi_freq;
56 static unsigned int cur_freq;
57 static unsigned int sleep_freq;
58 static unsigned long transition_latency;
59 
60 /*
61  * Different models uses different mechanisms to switch the frequency
62  */
63 static int (*set_speed_proc)(int low_speed);
64 static unsigned int (*get_speed_proc)(void);
65 
66 /*
67  * Some definitions used by the various speedprocs
68  */
69 static u32 voltage_gpio;
70 static u32 frequency_gpio;
71 static u32 slew_done_gpio;
72 static int no_schedule;
73 static int has_cpu_l2lve;
74 static int is_pmu_based;
75 
76 /* There are only two frequency states for each processor. Values
77  * are in kHz for the time being.
78  */
79 #define CPUFREQ_HIGH                  0
80 #define CPUFREQ_LOW                   1
81 
82 static struct cpufreq_frequency_table pmac_cpu_freqs[] = {
83 	{CPUFREQ_HIGH, 		0},
84 	{CPUFREQ_LOW,		0},
85 	{0,			CPUFREQ_TABLE_END},
86 };
87 
88 static struct freq_attr* pmac_cpu_freqs_attr[] = {
89 	&cpufreq_freq_attr_scaling_available_freqs,
90 	NULL,
91 };
92 
93 static inline void local_delay(unsigned long ms)
94 {
95 	if (no_schedule)
96 		mdelay(ms);
97 	else
98 		msleep(ms);
99 }
100 
101 #ifdef DEBUG_FREQ
102 static inline void debug_calc_bogomips(void)
103 {
104 	/* This will cause a recalc of bogomips and display the
105 	 * result. We backup/restore the value to avoid affecting the
106 	 * core cpufreq framework's own calculation.
107 	 */
108 	unsigned long save_lpj = loops_per_jiffy;
109 	calibrate_delay();
110 	loops_per_jiffy = save_lpj;
111 }
112 #endif /* DEBUG_FREQ */
113 
114 /* Switch CPU speed under 750FX CPU control
115  */
116 static int cpu_750fx_cpu_speed(int low_speed)
117 {
118 	u32 hid2;
119 
120 	if (low_speed == 0) {
121 		/* ramping up, set voltage first */
122 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x05);
123 		/* Make sure we sleep for at least 1ms */
124 		local_delay(10);
125 
126 		/* tweak L2 for high voltage */
127 		if (has_cpu_l2lve) {
128 			hid2 = mfspr(SPRN_HID2);
129 			hid2 &= ~0x2000;
130 			mtspr(SPRN_HID2, hid2);
131 		}
132 	}
133 #ifdef CONFIG_6xx
134 	low_choose_750fx_pll(low_speed);
135 #endif
136 	if (low_speed == 1) {
137 		/* tweak L2 for low voltage */
138 		if (has_cpu_l2lve) {
139 			hid2 = mfspr(SPRN_HID2);
140 			hid2 |= 0x2000;
141 			mtspr(SPRN_HID2, hid2);
142 		}
143 
144 		/* ramping down, set voltage last */
145 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x04);
146 		local_delay(10);
147 	}
148 
149 	return 0;
150 }
151 
152 static unsigned int cpu_750fx_get_cpu_speed(void)
153 {
154 	if (mfspr(SPRN_HID1) & HID1_PS)
155 		return low_freq;
156 	else
157 		return hi_freq;
158 }
159 
160 /* Switch CPU speed using DFS */
161 static int dfs_set_cpu_speed(int low_speed)
162 {
163 	if (low_speed == 0) {
164 		/* ramping up, set voltage first */
165 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x05);
166 		/* Make sure we sleep for at least 1ms */
167 		local_delay(1);
168 	}
169 
170 	/* set frequency */
171 #ifdef CONFIG_6xx
172 	low_choose_7447a_dfs(low_speed);
173 #endif
174 	udelay(100);
175 
176 	if (low_speed == 1) {
177 		/* ramping down, set voltage last */
178 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x04);
179 		local_delay(1);
180 	}
181 
182 	return 0;
183 }
184 
185 static unsigned int dfs_get_cpu_speed(void)
186 {
187 	if (mfspr(SPRN_HID1) & HID1_DFS)
188 		return low_freq;
189 	else
190 		return hi_freq;
191 }
192 
193 
194 /* Switch CPU speed using slewing GPIOs
195  */
196 static int gpios_set_cpu_speed(int low_speed)
197 {
198 	int gpio, timeout = 0;
199 
200 	/* If ramping up, set voltage first */
201 	if (low_speed == 0) {
202 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x05);
203 		/* Delay is way too big but it's ok, we schedule */
204 		local_delay(10);
205 	}
206 
207 	/* Set frequency */
208 	gpio = 	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, frequency_gpio, 0);
209 	if (low_speed == ((gpio & 0x01) == 0))
210 		goto skip;
211 
212 	pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, frequency_gpio,
213 			  low_speed ? 0x04 : 0x05);
214 	udelay(200);
215 	do {
216 		if (++timeout > 100)
217 			break;
218 		local_delay(1);
219 		gpio = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, slew_done_gpio, 0);
220 	} while((gpio & 0x02) == 0);
221  skip:
222 	/* If ramping down, set voltage last */
223 	if (low_speed == 1) {
224 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, voltage_gpio, 0x04);
225 		/* Delay is way too big but it's ok, we schedule */
226 		local_delay(10);
227 	}
228 
229 #ifdef DEBUG_FREQ
230 	debug_calc_bogomips();
231 #endif
232 
233 	return 0;
234 }
235 
236 /* Switch CPU speed under PMU control
237  */
238 static int pmu_set_cpu_speed(int low_speed)
239 {
240 	struct adb_request req;
241 	unsigned long save_l2cr;
242 	unsigned long save_l3cr;
243 	unsigned int pic_prio;
244 	unsigned long flags;
245 
246 	preempt_disable();
247 
248 #ifdef DEBUG_FREQ
249 	printk(KERN_DEBUG "HID1, before: %x\n", mfspr(SPRN_HID1));
250 #endif
251 	pmu_suspend();
252 
253 	/* Disable all interrupt sources on openpic */
254  	pic_prio = mpic_cpu_get_priority();
255 	mpic_cpu_set_priority(0xf);
256 
257 	/* Make sure the decrementer won't interrupt us */
258 	asm volatile("mtdec %0" : : "r" (0x7fffffff));
259 	/* Make sure any pending DEC interrupt occurring while we did
260 	 * the above didn't re-enable the DEC */
261 	mb();
262 	asm volatile("mtdec %0" : : "r" (0x7fffffff));
263 
264 	/* We can now disable MSR_EE */
265 	local_irq_save(flags);
266 
267 	/* Giveup the FPU & vec */
268 	enable_kernel_fp();
269 
270 #ifdef CONFIG_ALTIVEC
271 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
272 		enable_kernel_altivec();
273 #endif /* CONFIG_ALTIVEC */
274 
275 	/* Save & disable L2 and L3 caches */
276 	save_l3cr = _get_L3CR();	/* (returns -1 if not available) */
277 	save_l2cr = _get_L2CR();	/* (returns -1 if not available) */
278 
279 	/* Send the new speed command. My assumption is that this command
280 	 * will cause PLL_CFG[0..3] to be changed next time CPU goes to sleep
281 	 */
282 	pmu_request(&req, NULL, 6, PMU_CPU_SPEED, 'W', 'O', 'O', 'F', low_speed);
283 	while (!req.complete)
284 		pmu_poll();
285 
286 	/* Prepare the northbridge for the speed transition */
287 	pmac_call_feature(PMAC_FTR_SLEEP_STATE,NULL,1,1);
288 
289 	/* Call low level code to backup CPU state and recover from
290 	 * hardware reset
291 	 */
292 	low_sleep_handler();
293 
294 	/* Restore the northbridge */
295 	pmac_call_feature(PMAC_FTR_SLEEP_STATE,NULL,1,0);
296 
297 	/* Restore L2 cache */
298 	if (save_l2cr != 0xffffffff && (save_l2cr & L2CR_L2E) != 0)
299  		_set_L2CR(save_l2cr);
300 	/* Restore L3 cache */
301 	if (save_l3cr != 0xffffffff && (save_l3cr & L3CR_L3E) != 0)
302  		_set_L3CR(save_l3cr);
303 
304 	/* Restore userland MMU context */
305 	switch_mmu_context(NULL, current->active_mm);
306 
307 #ifdef DEBUG_FREQ
308 	printk(KERN_DEBUG "HID1, after: %x\n", mfspr(SPRN_HID1));
309 #endif
310 
311 	/* Restore low level PMU operations */
312 	pmu_unlock();
313 
314 	/*
315 	 * Restore decrementer; we'll take a decrementer interrupt
316 	 * as soon as interrupts are re-enabled and the generic
317 	 * clockevents code will reprogram it with the right value.
318 	 */
319 	set_dec(1);
320 
321 	/* Restore interrupts */
322  	mpic_cpu_set_priority(pic_prio);
323 
324 	/* Let interrupts flow again ... */
325 	local_irq_restore(flags);
326 
327 #ifdef DEBUG_FREQ
328 	debug_calc_bogomips();
329 #endif
330 
331 	pmu_resume();
332 
333 	preempt_enable();
334 
335 	return 0;
336 }
337 
338 static int do_set_cpu_speed(struct cpufreq_policy *policy, int speed_mode,
339 		int notify)
340 {
341 	struct cpufreq_freqs freqs;
342 	unsigned long l3cr;
343 	static unsigned long prev_l3cr;
344 
345 	freqs.old = cur_freq;
346 	freqs.new = (speed_mode == CPUFREQ_HIGH) ? hi_freq : low_freq;
347 
348 	if (freqs.old == freqs.new)
349 		return 0;
350 
351 	if (notify)
352 		cpufreq_notify_transition(policy, &freqs, CPUFREQ_PRECHANGE);
353 	if (speed_mode == CPUFREQ_LOW &&
354 	    cpu_has_feature(CPU_FTR_L3CR)) {
355 		l3cr = _get_L3CR();
356 		if (l3cr & L3CR_L3E) {
357 			prev_l3cr = l3cr;
358 			_set_L3CR(0);
359 		}
360 	}
361 	set_speed_proc(speed_mode == CPUFREQ_LOW);
362 	if (speed_mode == CPUFREQ_HIGH &&
363 	    cpu_has_feature(CPU_FTR_L3CR)) {
364 		l3cr = _get_L3CR();
365 		if ((prev_l3cr & L3CR_L3E) && l3cr != prev_l3cr)
366 			_set_L3CR(prev_l3cr);
367 	}
368 	if (notify)
369 		cpufreq_notify_transition(policy, &freqs, CPUFREQ_POSTCHANGE);
370 	cur_freq = (speed_mode == CPUFREQ_HIGH) ? hi_freq : low_freq;
371 
372 	return 0;
373 }
374 
375 static unsigned int pmac_cpufreq_get_speed(unsigned int cpu)
376 {
377 	return cur_freq;
378 }
379 
380 static int pmac_cpufreq_verify(struct cpufreq_policy *policy)
381 {
382 	return cpufreq_frequency_table_verify(policy, pmac_cpu_freqs);
383 }
384 
385 static int pmac_cpufreq_target(	struct cpufreq_policy *policy,
386 					unsigned int target_freq,
387 					unsigned int relation)
388 {
389 	unsigned int    newstate = 0;
390 	int		rc;
391 
392 	if (cpufreq_frequency_table_target(policy, pmac_cpu_freqs,
393 			target_freq, relation, &newstate))
394 		return -EINVAL;
395 
396 	rc = do_set_cpu_speed(policy, newstate, 1);
397 
398 	ppc_proc_freq = cur_freq * 1000ul;
399 	return rc;
400 }
401 
402 static int pmac_cpufreq_cpu_init(struct cpufreq_policy *policy)
403 {
404 	if (policy->cpu != 0)
405 		return -ENODEV;
406 
407 	policy->cpuinfo.transition_latency	= transition_latency;
408 	policy->cur = cur_freq;
409 
410 	cpufreq_frequency_table_get_attr(pmac_cpu_freqs, policy->cpu);
411 	return cpufreq_frequency_table_cpuinfo(policy, pmac_cpu_freqs);
412 }
413 
414 static u32 read_gpio(struct device_node *np)
415 {
416 	const u32 *reg = of_get_property(np, "reg", NULL);
417 	u32 offset;
418 
419 	if (reg == NULL)
420 		return 0;
421 	/* That works for all keylargos but shall be fixed properly
422 	 * some day... The problem is that it seems we can't rely
423 	 * on the "reg" property of the GPIO nodes, they are either
424 	 * relative to the base of KeyLargo or to the base of the
425 	 * GPIO space, and the device-tree doesn't help.
426 	 */
427 	offset = *reg;
428 	if (offset < KEYLARGO_GPIO_LEVELS0)
429 		offset += KEYLARGO_GPIO_LEVELS0;
430 	return offset;
431 }
432 
433 static int pmac_cpufreq_suspend(struct cpufreq_policy *policy)
434 {
435 	/* Ok, this could be made a bit smarter, but let's be robust for now. We
436 	 * always force a speed change to high speed before sleep, to make sure
437 	 * we have appropriate voltage and/or bus speed for the wakeup process,
438 	 * and to make sure our loops_per_jiffies are "good enough", that is will
439 	 * not cause too short delays if we sleep in low speed and wake in high
440 	 * speed..
441 	 */
442 	no_schedule = 1;
443 	sleep_freq = cur_freq;
444 	if (cur_freq == low_freq && !is_pmu_based)
445 		do_set_cpu_speed(policy, CPUFREQ_HIGH, 0);
446 	return 0;
447 }
448 
449 static int pmac_cpufreq_resume(struct cpufreq_policy *policy)
450 {
451 	/* If we resume, first check if we have a get() function */
452 	if (get_speed_proc)
453 		cur_freq = get_speed_proc();
454 	else
455 		cur_freq = 0;
456 
457 	/* We don't, hrm... we don't really know our speed here, best
458 	 * is that we force a switch to whatever it was, which is
459 	 * probably high speed due to our suspend() routine
460 	 */
461 	do_set_cpu_speed(policy, sleep_freq == low_freq ?
462 			 CPUFREQ_LOW : CPUFREQ_HIGH, 0);
463 
464 	ppc_proc_freq = cur_freq * 1000ul;
465 
466 	no_schedule = 0;
467 	return 0;
468 }
469 
470 static struct cpufreq_driver pmac_cpufreq_driver = {
471 	.verify 	= pmac_cpufreq_verify,
472 	.target 	= pmac_cpufreq_target,
473 	.get		= pmac_cpufreq_get_speed,
474 	.init		= pmac_cpufreq_cpu_init,
475 	.suspend	= pmac_cpufreq_suspend,
476 	.resume		= pmac_cpufreq_resume,
477 	.flags		= CPUFREQ_PM_NO_WARN,
478 	.attr		= pmac_cpu_freqs_attr,
479 	.name		= "powermac",
480 	.owner		= THIS_MODULE,
481 };
482 
483 
484 static int pmac_cpufreq_init_MacRISC3(struct device_node *cpunode)
485 {
486 	struct device_node *volt_gpio_np = of_find_node_by_name(NULL,
487 								"voltage-gpio");
488 	struct device_node *freq_gpio_np = of_find_node_by_name(NULL,
489 								"frequency-gpio");
490 	struct device_node *slew_done_gpio_np = of_find_node_by_name(NULL,
491 								     "slewing-done");
492 	const u32 *value;
493 
494 	/*
495 	 * Check to see if it's GPIO driven or PMU only
496 	 *
497 	 * The way we extract the GPIO address is slightly hackish, but it
498 	 * works well enough for now. We need to abstract the whole GPIO
499 	 * stuff sooner or later anyway
500 	 */
501 
502 	if (volt_gpio_np)
503 		voltage_gpio = read_gpio(volt_gpio_np);
504 	if (freq_gpio_np)
505 		frequency_gpio = read_gpio(freq_gpio_np);
506 	if (slew_done_gpio_np)
507 		slew_done_gpio = read_gpio(slew_done_gpio_np);
508 
509 	/* If we use the frequency GPIOs, calculate the min/max speeds based
510 	 * on the bus frequencies
511 	 */
512 	if (frequency_gpio && slew_done_gpio) {
513 		int lenp, rc;
514 		const u32 *freqs, *ratio;
515 
516 		freqs = of_get_property(cpunode, "bus-frequencies", &lenp);
517 		lenp /= sizeof(u32);
518 		if (freqs == NULL || lenp != 2) {
519 			printk(KERN_ERR "cpufreq: bus-frequencies incorrect or missing\n");
520 			return 1;
521 		}
522 		ratio = of_get_property(cpunode, "processor-to-bus-ratio*2",
523 						NULL);
524 		if (ratio == NULL) {
525 			printk(KERN_ERR "cpufreq: processor-to-bus-ratio*2 missing\n");
526 			return 1;
527 		}
528 
529 		/* Get the min/max bus frequencies */
530 		low_freq = min(freqs[0], freqs[1]);
531 		hi_freq = max(freqs[0], freqs[1]);
532 
533 		/* Grrrr.. It _seems_ that the device-tree is lying on the low bus
534 		 * frequency, it claims it to be around 84Mhz on some models while
535 		 * it appears to be approx. 101Mhz on all. Let's hack around here...
536 		 * fortunately, we don't need to be too precise
537 		 */
538 		if (low_freq < 98000000)
539 			low_freq = 101000000;
540 
541 		/* Convert those to CPU core clocks */
542 		low_freq = (low_freq * (*ratio)) / 2000;
543 		hi_freq = (hi_freq * (*ratio)) / 2000;
544 
545 		/* Now we get the frequencies, we read the GPIO to see what is out current
546 		 * speed
547 		 */
548 		rc = pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, frequency_gpio, 0);
549 		cur_freq = (rc & 0x01) ? hi_freq : low_freq;
550 
551 		set_speed_proc = gpios_set_cpu_speed;
552 		return 1;
553 	}
554 
555 	/* If we use the PMU, look for the min & max frequencies in the
556 	 * device-tree
557 	 */
558 	value = of_get_property(cpunode, "min-clock-frequency", NULL);
559 	if (!value)
560 		return 1;
561 	low_freq = (*value) / 1000;
562 	/* The PowerBook G4 12" (PowerBook6,1) has an error in the device-tree
563 	 * here */
564 	if (low_freq < 100000)
565 		low_freq *= 10;
566 
567 	value = of_get_property(cpunode, "max-clock-frequency", NULL);
568 	if (!value)
569 		return 1;
570 	hi_freq = (*value) / 1000;
571 	set_speed_proc = pmu_set_cpu_speed;
572 	is_pmu_based = 1;
573 
574 	return 0;
575 }
576 
577 static int pmac_cpufreq_init_7447A(struct device_node *cpunode)
578 {
579 	struct device_node *volt_gpio_np;
580 
581 	if (of_get_property(cpunode, "dynamic-power-step", NULL) == NULL)
582 		return 1;
583 
584 	volt_gpio_np = of_find_node_by_name(NULL, "cpu-vcore-select");
585 	if (volt_gpio_np)
586 		voltage_gpio = read_gpio(volt_gpio_np);
587 	if (!voltage_gpio){
588 		printk(KERN_ERR "cpufreq: missing cpu-vcore-select gpio\n");
589 		return 1;
590 	}
591 
592 	/* OF only reports the high frequency */
593 	hi_freq = cur_freq;
594 	low_freq = cur_freq/2;
595 
596 	/* Read actual frequency from CPU */
597 	cur_freq = dfs_get_cpu_speed();
598 	set_speed_proc = dfs_set_cpu_speed;
599 	get_speed_proc = dfs_get_cpu_speed;
600 
601 	return 0;
602 }
603 
604 static int pmac_cpufreq_init_750FX(struct device_node *cpunode)
605 {
606 	struct device_node *volt_gpio_np;
607 	u32 pvr;
608 	const u32 *value;
609 
610 	if (of_get_property(cpunode, "dynamic-power-step", NULL) == NULL)
611 		return 1;
612 
613 	hi_freq = cur_freq;
614 	value = of_get_property(cpunode, "reduced-clock-frequency", NULL);
615 	if (!value)
616 		return 1;
617 	low_freq = (*value) / 1000;
618 
619 	volt_gpio_np = of_find_node_by_name(NULL, "cpu-vcore-select");
620 	if (volt_gpio_np)
621 		voltage_gpio = read_gpio(volt_gpio_np);
622 
623 	pvr = mfspr(SPRN_PVR);
624 	has_cpu_l2lve = !((pvr & 0xf00) == 0x100);
625 
626 	set_speed_proc = cpu_750fx_cpu_speed;
627 	get_speed_proc = cpu_750fx_get_cpu_speed;
628 	cur_freq = cpu_750fx_get_cpu_speed();
629 
630 	return 0;
631 }
632 
633 /* Currently, we support the following machines:
634  *
635  *  - Titanium PowerBook 1Ghz (PMU based, 667Mhz & 1Ghz)
636  *  - Titanium PowerBook 800 (PMU based, 667Mhz & 800Mhz)
637  *  - Titanium PowerBook 400 (PMU based, 300Mhz & 400Mhz)
638  *  - Titanium PowerBook 500 (PMU based, 300Mhz & 500Mhz)
639  *  - iBook2 500/600 (PMU based, 400Mhz & 500/600Mhz)
640  *  - iBook2 700 (CPU based, 400Mhz & 700Mhz, support low voltage)
641  *  - Recent MacRISC3 laptops
642  *  - All new machines with 7447A CPUs
643  */
644 static int __init pmac_cpufreq_setup(void)
645 {
646 	struct device_node	*cpunode;
647 	const u32		*value;
648 
649 	if (strstr(cmd_line, "nocpufreq"))
650 		return 0;
651 
652 	/* Assume only one CPU */
653 	cpunode = of_find_node_by_type(NULL, "cpu");
654 	if (!cpunode)
655 		goto out;
656 
657 	/* Get current cpu clock freq */
658 	value = of_get_property(cpunode, "clock-frequency", NULL);
659 	if (!value)
660 		goto out;
661 	cur_freq = (*value) / 1000;
662 	transition_latency = CPUFREQ_ETERNAL;
663 
664 	/*  Check for 7447A based MacRISC3 */
665 	if (of_machine_is_compatible("MacRISC3") &&
666 	    of_get_property(cpunode, "dynamic-power-step", NULL) &&
667 	    PVR_VER(mfspr(SPRN_PVR)) == 0x8003) {
668 		pmac_cpufreq_init_7447A(cpunode);
669 		transition_latency = 8000000;
670 	/* Check for other MacRISC3 machines */
671 	} else if (of_machine_is_compatible("PowerBook3,4") ||
672 		   of_machine_is_compatible("PowerBook3,5") ||
673 		   of_machine_is_compatible("MacRISC3")) {
674 		pmac_cpufreq_init_MacRISC3(cpunode);
675 	/* Else check for iBook2 500/600 */
676 	} else if (of_machine_is_compatible("PowerBook4,1")) {
677 		hi_freq = cur_freq;
678 		low_freq = 400000;
679 		set_speed_proc = pmu_set_cpu_speed;
680 		is_pmu_based = 1;
681 	}
682 	/* Else check for TiPb 550 */
683 	else if (of_machine_is_compatible("PowerBook3,3") && cur_freq == 550000) {
684 		hi_freq = cur_freq;
685 		low_freq = 500000;
686 		set_speed_proc = pmu_set_cpu_speed;
687 		is_pmu_based = 1;
688 	}
689 	/* Else check for TiPb 400 & 500 */
690 	else if (of_machine_is_compatible("PowerBook3,2")) {
691 		/* We only know about the 400 MHz and the 500Mhz model
692 		 * they both have 300 MHz as low frequency
693 		 */
694 		if (cur_freq < 350000 || cur_freq > 550000)
695 			goto out;
696 		hi_freq = cur_freq;
697 		low_freq = 300000;
698 		set_speed_proc = pmu_set_cpu_speed;
699 		is_pmu_based = 1;
700 	}
701 	/* Else check for 750FX */
702 	else if (PVR_VER(mfspr(SPRN_PVR)) == 0x7000)
703 		pmac_cpufreq_init_750FX(cpunode);
704 out:
705 	of_node_put(cpunode);
706 	if (set_speed_proc == NULL)
707 		return -ENODEV;
708 
709 	pmac_cpu_freqs[CPUFREQ_LOW].frequency = low_freq;
710 	pmac_cpu_freqs[CPUFREQ_HIGH].frequency = hi_freq;
711 	ppc_proc_freq = cur_freq * 1000ul;
712 
713 	printk(KERN_INFO "Registering PowerMac CPU frequency driver\n");
714 	printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Boot: %d Mhz\n",
715 	       low_freq/1000, hi_freq/1000, cur_freq/1000);
716 
717 	return cpufreq_register_driver(&pmac_cpufreq_driver);
718 }
719 
720 module_init(pmac_cpufreq_setup);
721 
722