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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 (hwclock = NULL;
503 (hwclock = of_find_node_by_name(hwclock, "i2c-hwclock")) != NULL;){
504 const char *loc = of_get_property(hwclock,
505 "hwctrl-location", NULL);
506 if (loc == NULL)
507 continue;
508 if (strcmp(loc, "CPU CLOCK"))
509 continue;
510 if (!of_get_property(hwclock, "platform-get-frequency", NULL))
511 continue;
512 break;
513 }
514 if (hwclock == NULL) {
515 printk(KERN_ERR "cpufreq: Can't find i2c clock chip !\n");
516 rc = -ENODEV;
517 goto bail;
518 }
519
520 DBG("cpufreq: i2c clock chip found: %s\n", hwclock->full_name);
521
522 /* Now get all the platform functions */
523 pfunc_cpu_getfreq =
524 pmf_find_function(hwclock, "get-frequency");
525 pfunc_cpu_setfreq_high =
526 pmf_find_function(hwclock, "set-frequency-high");
527 pfunc_cpu_setfreq_low =
528 pmf_find_function(hwclock, "set-frequency-low");
529 pfunc_slewing_done =
530 pmf_find_function(hwclock, "slewing-done");
531 pfunc_cpu0_volt_high =
532 pmf_find_function(hwclock, "set-voltage-high-0");
533 pfunc_cpu0_volt_low =
534 pmf_find_function(hwclock, "set-voltage-low-0");
535 pfunc_cpu1_volt_high =
536 pmf_find_function(hwclock, "set-voltage-high-1");
537 pfunc_cpu1_volt_low =
538 pmf_find_function(hwclock, "set-voltage-low-1");
539
540 /* Check we have minimum requirements */
541 if (pfunc_cpu_getfreq == NULL || pfunc_cpu_setfreq_high == NULL ||
542 pfunc_cpu_setfreq_low == NULL || pfunc_slewing_done == NULL) {
543 printk(KERN_ERR "cpufreq: Can't find platform functions !\n");
544 rc = -ENODEV;
545 goto bail;
546 }
547
548 /* Check that we have complete sets */
549 if (pfunc_cpu0_volt_high == NULL || pfunc_cpu0_volt_low == NULL) {
550 pmf_put_function(pfunc_cpu0_volt_high);
551 pmf_put_function(pfunc_cpu0_volt_low);
552 pfunc_cpu0_volt_high = pfunc_cpu0_volt_low = NULL;
553 has_volt = 0;
554 }
555 if (!has_volt ||
556 pfunc_cpu1_volt_high == NULL || pfunc_cpu1_volt_low == NULL) {
557 pmf_put_function(pfunc_cpu1_volt_high);
558 pmf_put_function(pfunc_cpu1_volt_low);
559 pfunc_cpu1_volt_high = pfunc_cpu1_volt_low = NULL;
560 }
561
562 /* Note: The device tree also contains a "platform-set-values"
563 * function for which I haven't quite figured out the usage. It
564 * might have to be called on init and/or wakeup, I'm not too sure
565 * but things seem to work fine without it so far ...
566 */
567
568 /* Get max frequency from device-tree */
569 valp = of_get_property(cpunode, "clock-frequency", NULL);
570 if (!valp) {
571 printk(KERN_ERR "cpufreq: Can't find CPU frequency !\n");
572 rc = -ENODEV;
573 goto bail;
574 }
575
576 max_freq = (*valp)/1000;
577
578 /* Now calculate reduced frequency by using the cpuid input freq
579 * ratio. This requires 64 bits math unless we are willing to lose
580 * some precision
581 */
582 ih = *((u32 *)(eeprom + 0x10));
583 il = *((u32 *)(eeprom + 0x20));
584
585 /* Check for machines with no useful settings */
586 if (il == ih) {
587 printk(KERN_WARNING "cpufreq: No low frequency mode available"
588 " on this model !\n");
589 rc = -ENODEV;
590 goto bail;
591 }
592
593 min_freq = 0;
594 if (ih != 0 && il != 0)
595 min_freq = (max_freq * il) / ih;
596
597 /* Sanity check */
598 if (min_freq >= max_freq || min_freq < 1000) {
599 printk(KERN_ERR "cpufreq: Can't calculate low frequency !\n");
600 rc = -ENXIO;
601 goto bail;
602 }
603 g5_cpu_freqs[0].frequency = max_freq;
604 g5_cpu_freqs[1].frequency = min_freq;
605
606 /* Based on a measurement on Xserve G5, rounded up. */
607 transition_latency = 10 * NSEC_PER_MSEC;
608
609 /* Set callbacks */
610 g5_switch_volt = g5_pfunc_switch_volt;
611 g5_switch_freq = g5_pfunc_switch_freq;
612 g5_query_freq = g5_pfunc_query_freq;
613
614 /* Force apply current frequency to make sure everything is in
615 * sync (voltage is right for example). Firmware may leave us with
616 * a strange setting ...
617 */
618 g5_switch_volt(CPUFREQ_HIGH);
619 msleep(10);
620 g5_pmode_cur = -1;
621 g5_switch_freq(g5_query_freq());
622
623 printk(KERN_INFO "Registering G5 CPU frequency driver\n");
624 printk(KERN_INFO "Frequency method: i2c/pfunc, "
625 "Voltage method: %s\n", has_volt ? "i2c/pfunc" : "none");
626 printk(KERN_INFO "Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
627 g5_cpu_freqs[1].frequency/1000,
628 g5_cpu_freqs[0].frequency/1000,
629 g5_cpu_freqs[g5_pmode_cur].frequency/1000);
630
631 rc = cpufreq_register_driver(&g5_cpufreq_driver);
632 bail:
633 if (rc != 0) {
634 pmf_put_function(pfunc_cpu_getfreq);
635 pmf_put_function(pfunc_cpu_setfreq_high);
636 pmf_put_function(pfunc_cpu_setfreq_low);
637 pmf_put_function(pfunc_slewing_done);
638 pmf_put_function(pfunc_cpu0_volt_high);
639 pmf_put_function(pfunc_cpu0_volt_low);
640 pmf_put_function(pfunc_cpu1_volt_high);
641 pmf_put_function(pfunc_cpu1_volt_low);
642 }
643 of_node_put(hwclock);
644 of_node_put(cpuid);
645 of_node_put(cpunode);
646
647 return rc;
648}
649
650static int __init g5_cpufreq_init(void)
651{
652 struct device_node *cpunode;
653 int rc = 0;
654
655 /* Get first CPU node */
656 cpunode = of_cpu_device_node_get(0);
657 if (cpunode == NULL) {
658 pr_err("cpufreq: Can't find any CPU node\n");
659 return -ENODEV;
660 }
661
662 if (of_machine_is_compatible("PowerMac7,2") ||
663 of_machine_is_compatible("PowerMac7,3") ||
664 of_machine_is_compatible("RackMac3,1"))
665 rc = g5_pm72_cpufreq_init(cpunode);
666#ifdef CONFIG_PMAC_SMU
667 else
668 rc = g5_neo2_cpufreq_init(cpunode);
669#endif /* CONFIG_PMAC_SMU */
670
671 return rc;
672}
673
674module_init(g5_cpufreq_init);
675
676
677MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2002 - 2005 Benjamin Herrenschmidt <benh@kernel.crashing.org>
4 * and Markus Demleitner <msdemlei@cl.uni-heidelberg.de>
5 *
6 * This driver adds basic cpufreq support for SMU & 970FX based G5 Macs,
7 * that is iMac G5 and latest single CPU desktop.
8 */
9
10#undef DEBUG
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/module.h>
15#include <linux/types.h>
16#include <linux/errno.h>
17#include <linux/kernel.h>
18#include <linux/delay.h>
19#include <linux/sched.h>
20#include <linux/cpufreq.h>
21#include <linux/init.h>
22#include <linux/completion.h>
23#include <linux/mutex.h>
24#include <linux/of.h>
25
26#include <asm/machdep.h>
27#include <asm/irq.h>
28#include <asm/sections.h>
29#include <asm/cputable.h>
30#include <asm/time.h>
31#include <asm/smu.h>
32#include <asm/pmac_pfunc.h>
33
34#define DBG(fmt...) pr_debug(fmt)
35
36/* see 970FX user manual */
37
38#define SCOM_PCR 0x0aa001 /* PCR scom addr */
39
40#define PCR_HILO_SELECT 0x80000000U /* 1 = PCR, 0 = PCRH */
41#define PCR_SPEED_FULL 0x00000000U /* 1:1 speed value */
42#define PCR_SPEED_HALF 0x00020000U /* 1:2 speed value */
43#define PCR_SPEED_QUARTER 0x00040000U /* 1:4 speed value */
44#define PCR_SPEED_MASK 0x000e0000U /* speed mask */
45#define PCR_SPEED_SHIFT 17
46#define PCR_FREQ_REQ_VALID 0x00010000U /* freq request valid */
47#define PCR_VOLT_REQ_VALID 0x00008000U /* volt request valid */
48#define PCR_TARGET_TIME_MASK 0x00006000U /* target time */
49#define PCR_STATLAT_MASK 0x00001f00U /* STATLAT value */
50#define PCR_SNOOPLAT_MASK 0x000000f0U /* SNOOPLAT value */
51#define PCR_SNOOPACC_MASK 0x0000000fU /* SNOOPACC value */
52
53#define SCOM_PSR 0x408001 /* PSR scom addr */
54/* warning: PSR is a 64 bits register */
55#define PSR_CMD_RECEIVED 0x2000000000000000U /* command received */
56#define PSR_CMD_COMPLETED 0x1000000000000000U /* command completed */
57#define PSR_CUR_SPEED_MASK 0x0300000000000000U /* current speed */
58#define PSR_CUR_SPEED_SHIFT (56)
59
60/*
61 * The G5 only supports two frequencies (Quarter speed is not supported)
62 */
63#define CPUFREQ_HIGH 0
64#define CPUFREQ_LOW 1
65
66static struct cpufreq_frequency_table g5_cpu_freqs[] = {
67 {0, CPUFREQ_HIGH, 0},
68 {0, CPUFREQ_LOW, 0},
69 {0, 0, CPUFREQ_TABLE_END},
70};
71
72/* Power mode data is an array of the 32 bits PCR values to use for
73 * the various frequencies, retrieved from the device-tree
74 */
75static int g5_pmode_cur;
76
77static void (*g5_switch_volt)(int speed_mode);
78static int (*g5_switch_freq)(int speed_mode);
79static int (*g5_query_freq)(void);
80
81static unsigned long transition_latency;
82
83#ifdef CONFIG_PMAC_SMU
84
85static const u32 *g5_pmode_data;
86static int g5_pmode_max;
87
88static struct smu_sdbp_fvt *g5_fvt_table; /* table of op. points */
89static int g5_fvt_count; /* number of op. points */
90static int g5_fvt_cur; /* current op. point */
91
92/*
93 * SMU based voltage switching for Neo2 platforms
94 */
95
96static void g5_smu_switch_volt(int speed_mode)
97{
98 struct smu_simple_cmd cmd;
99
100 DECLARE_COMPLETION_ONSTACK(comp);
101 smu_queue_simple(&cmd, SMU_CMD_POWER_COMMAND, 8, smu_done_complete,
102 &comp, 'V', 'S', 'L', 'E', 'W',
103 0xff, g5_fvt_cur+1, speed_mode);
104 wait_for_completion(&comp);
105}
106
107/*
108 * Platform function based voltage/vdnap switching for Neo2
109 */
110
111static struct pmf_function *pfunc_set_vdnap0;
112static struct pmf_function *pfunc_vdnap0_complete;
113
114static void g5_vdnap_switch_volt(int speed_mode)
115{
116 struct pmf_args args;
117 u32 slew, done = 0;
118 unsigned long timeout;
119
120 slew = (speed_mode == CPUFREQ_LOW) ? 1 : 0;
121 args.count = 1;
122 args.u[0].p = &slew;
123
124 pmf_call_one(pfunc_set_vdnap0, &args);
125
126 /* It's an irq GPIO so we should be able to just block here,
127 * I'll do that later after I've properly tested the IRQ code for
128 * platform functions
129 */
130 timeout = jiffies + HZ/10;
131 while(!time_after(jiffies, timeout)) {
132 args.count = 1;
133 args.u[0].p = &done;
134 pmf_call_one(pfunc_vdnap0_complete, &args);
135 if (done)
136 break;
137 usleep_range(1000, 1000);
138 }
139 if (done == 0)
140 pr_warn("Timeout in clock slewing !\n");
141}
142
143
144/*
145 * SCOM based frequency switching for 970FX rev3
146 */
147static int g5_scom_switch_freq(int speed_mode)
148{
149 unsigned long flags;
150 int to;
151
152 /* If frequency is going up, first ramp up the voltage */
153 if (speed_mode < g5_pmode_cur)
154 g5_switch_volt(speed_mode);
155
156 local_irq_save(flags);
157
158 /* Clear PCR high */
159 scom970_write(SCOM_PCR, 0);
160 /* Clear PCR low */
161 scom970_write(SCOM_PCR, PCR_HILO_SELECT | 0);
162 /* Set PCR low */
163 scom970_write(SCOM_PCR, PCR_HILO_SELECT |
164 g5_pmode_data[speed_mode]);
165
166 /* Wait for completion */
167 for (to = 0; to < 10; to++) {
168 unsigned long psr = scom970_read(SCOM_PSR);
169
170 if ((psr & PSR_CMD_RECEIVED) == 0 &&
171 (((psr >> PSR_CUR_SPEED_SHIFT) ^
172 (g5_pmode_data[speed_mode] >> PCR_SPEED_SHIFT)) & 0x3)
173 == 0)
174 break;
175 if (psr & PSR_CMD_COMPLETED)
176 break;
177 udelay(100);
178 }
179
180 local_irq_restore(flags);
181
182 /* If frequency is going down, last ramp the voltage */
183 if (speed_mode > g5_pmode_cur)
184 g5_switch_volt(speed_mode);
185
186 g5_pmode_cur = speed_mode;
187 ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul;
188
189 return 0;
190}
191
192static int g5_scom_query_freq(void)
193{
194 unsigned long psr = scom970_read(SCOM_PSR);
195 int i;
196
197 for (i = 0; i <= g5_pmode_max; i++)
198 if ((((psr >> PSR_CUR_SPEED_SHIFT) ^
199 (g5_pmode_data[i] >> PCR_SPEED_SHIFT)) & 0x3) == 0)
200 break;
201 return i;
202}
203
204/*
205 * Fake voltage switching for platforms with missing support
206 */
207
208static void g5_dummy_switch_volt(int speed_mode)
209{
210}
211
212#endif /* CONFIG_PMAC_SMU */
213
214/*
215 * Platform function based voltage switching for PowerMac7,2 & 7,3
216 */
217
218static struct pmf_function *pfunc_cpu0_volt_high;
219static struct pmf_function *pfunc_cpu0_volt_low;
220static struct pmf_function *pfunc_cpu1_volt_high;
221static struct pmf_function *pfunc_cpu1_volt_low;
222
223static void g5_pfunc_switch_volt(int speed_mode)
224{
225 if (speed_mode == CPUFREQ_HIGH) {
226 if (pfunc_cpu0_volt_high)
227 pmf_call_one(pfunc_cpu0_volt_high, NULL);
228 if (pfunc_cpu1_volt_high)
229 pmf_call_one(pfunc_cpu1_volt_high, NULL);
230 } else {
231 if (pfunc_cpu0_volt_low)
232 pmf_call_one(pfunc_cpu0_volt_low, NULL);
233 if (pfunc_cpu1_volt_low)
234 pmf_call_one(pfunc_cpu1_volt_low, NULL);
235 }
236 usleep_range(10000, 10000); /* should be faster , to fix */
237}
238
239/*
240 * Platform function based frequency switching for PowerMac7,2 & 7,3
241 */
242
243static struct pmf_function *pfunc_cpu_setfreq_high;
244static struct pmf_function *pfunc_cpu_setfreq_low;
245static struct pmf_function *pfunc_cpu_getfreq;
246static struct pmf_function *pfunc_slewing_done;
247
248static int g5_pfunc_switch_freq(int speed_mode)
249{
250 struct pmf_args args;
251 u32 done = 0;
252 unsigned long timeout;
253 int rc;
254
255 DBG("g5_pfunc_switch_freq(%d)\n", speed_mode);
256
257 /* If frequency is going up, first ramp up the voltage */
258 if (speed_mode < g5_pmode_cur)
259 g5_switch_volt(speed_mode);
260
261 /* Do it */
262 if (speed_mode == CPUFREQ_HIGH)
263 rc = pmf_call_one(pfunc_cpu_setfreq_high, NULL);
264 else
265 rc = pmf_call_one(pfunc_cpu_setfreq_low, NULL);
266
267 if (rc)
268 pr_warn("pfunc switch error %d\n", rc);
269
270 /* It's an irq GPIO so we should be able to just block here,
271 * I'll do that later after I've properly tested the IRQ code for
272 * platform functions
273 */
274 timeout = jiffies + HZ/10;
275 while(!time_after(jiffies, timeout)) {
276 args.count = 1;
277 args.u[0].p = &done;
278 pmf_call_one(pfunc_slewing_done, &args);
279 if (done)
280 break;
281 usleep_range(500, 500);
282 }
283 if (done == 0)
284 pr_warn("Timeout in clock slewing !\n");
285
286 /* If frequency is going down, last ramp the voltage */
287 if (speed_mode > g5_pmode_cur)
288 g5_switch_volt(speed_mode);
289
290 g5_pmode_cur = speed_mode;
291 ppc_proc_freq = g5_cpu_freqs[speed_mode].frequency * 1000ul;
292
293 return 0;
294}
295
296static int g5_pfunc_query_freq(void)
297{
298 struct pmf_args args;
299 u32 val = 0;
300
301 args.count = 1;
302 args.u[0].p = &val;
303 pmf_call_one(pfunc_cpu_getfreq, &args);
304 return val ? CPUFREQ_HIGH : CPUFREQ_LOW;
305}
306
307
308/*
309 * Common interface to the cpufreq core
310 */
311
312static int g5_cpufreq_target(struct cpufreq_policy *policy, unsigned int index)
313{
314 return g5_switch_freq(index);
315}
316
317static unsigned int g5_cpufreq_get_speed(unsigned int cpu)
318{
319 return g5_cpu_freqs[g5_pmode_cur].frequency;
320}
321
322static int g5_cpufreq_cpu_init(struct cpufreq_policy *policy)
323{
324 cpufreq_generic_init(policy, g5_cpu_freqs, transition_latency);
325 return 0;
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 pr_err("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 pr_err("Can't find root of device tree\n");
407 goto bail_noprops;
408 }
409 pfunc_set_vdnap0 = pmf_find_function(root, "set-vdnap0");
410 pfunc_vdnap0_complete =
411 pmf_find_function(root, "slewing-done");
412 of_node_put(root);
413 if (pfunc_set_vdnap0 == NULL ||
414 pfunc_vdnap0_complete == NULL) {
415 pr_err("Can't find required platform function\n");
416 goto bail_noprops;
417 }
418
419 g5_switch_volt = g5_vdnap_switch_volt;
420 volt_method = "GPIO";
421 } else {
422 g5_switch_volt = g5_dummy_switch_volt;
423 volt_method = "none";
424 }
425
426 /*
427 * From what I see, clock-frequency is always the maximal frequency.
428 * The current driver can not slew sysclk yet, so we really only deal
429 * with powertune steps for now. We also only implement full freq and
430 * half freq in this version. So far, I haven't yet seen a machine
431 * supporting anything else.
432 */
433 valp = of_get_property(cpunode, "clock-frequency", NULL);
434 if (!valp)
435 return -ENODEV;
436 max_freq = (*valp)/1000;
437 g5_cpu_freqs[0].frequency = max_freq;
438 g5_cpu_freqs[1].frequency = max_freq/2;
439
440 /* Set callbacks */
441 transition_latency = 12000;
442 g5_switch_freq = g5_scom_switch_freq;
443 g5_query_freq = g5_scom_query_freq;
444 freq_method = "SCOM";
445
446 /* Force apply current frequency to make sure everything is in
447 * sync (voltage is right for example). Firmware may leave us with
448 * a strange setting ...
449 */
450 g5_switch_volt(CPUFREQ_HIGH);
451 msleep(10);
452 g5_pmode_cur = -1;
453 g5_switch_freq(g5_query_freq());
454
455 pr_info("Registering G5 CPU frequency driver\n");
456 pr_info("Frequency method: %s, Voltage method: %s\n",
457 freq_method, volt_method);
458 pr_info("Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
459 g5_cpu_freqs[1].frequency/1000,
460 g5_cpu_freqs[0].frequency/1000,
461 g5_cpu_freqs[g5_pmode_cur].frequency/1000);
462
463 rc = cpufreq_register_driver(&g5_cpufreq_driver);
464
465 /* We keep the CPU node on hold... hopefully, Apple G5 don't have
466 * hotplug CPU with a dynamic device-tree ...
467 */
468 return rc;
469
470 bail_noprops:
471 of_node_put(cpunode);
472
473 return rc;
474}
475
476#endif /* CONFIG_PMAC_SMU */
477
478
479static int __init g5_pm72_cpufreq_init(struct device_node *cpunode)
480{
481 struct device_node *cpuid = NULL, *hwclock = NULL;
482 const u8 *eeprom = NULL;
483 const u32 *valp;
484 u64 max_freq, min_freq, ih, il;
485 int has_volt = 1, rc = 0;
486
487 DBG("cpufreq: Initializing for PowerMac7,2, PowerMac7,3 and"
488 " RackMac3,1...\n");
489
490 /* Lookup the cpuid eeprom node */
491 cpuid = of_find_node_by_path("/u3@0,f8000000/i2c@f8001000/cpuid@a0");
492 if (cpuid != NULL)
493 eeprom = of_get_property(cpuid, "cpuid", NULL);
494 if (eeprom == NULL) {
495 pr_err("Can't find cpuid EEPROM !\n");
496 rc = -ENODEV;
497 goto bail;
498 }
499
500 /* Lookup the i2c hwclock */
501 for_each_node_by_name(hwclock, "i2c-hwclock") {
502 const char *loc = of_get_property(hwclock,
503 "hwctrl-location", NULL);
504 if (loc == NULL)
505 continue;
506 if (strcmp(loc, "CPU CLOCK"))
507 continue;
508 if (!of_property_present(hwclock, "platform-get-frequency"))
509 continue;
510 break;
511 }
512 if (hwclock == NULL) {
513 pr_err("Can't find i2c clock chip !\n");
514 rc = -ENODEV;
515 goto bail;
516 }
517
518 DBG("cpufreq: i2c clock chip found: %pOF\n", hwclock);
519
520 /* Now get all the platform functions */
521 pfunc_cpu_getfreq =
522 pmf_find_function(hwclock, "get-frequency");
523 pfunc_cpu_setfreq_high =
524 pmf_find_function(hwclock, "set-frequency-high");
525 pfunc_cpu_setfreq_low =
526 pmf_find_function(hwclock, "set-frequency-low");
527 pfunc_slewing_done =
528 pmf_find_function(hwclock, "slewing-done");
529 pfunc_cpu0_volt_high =
530 pmf_find_function(hwclock, "set-voltage-high-0");
531 pfunc_cpu0_volt_low =
532 pmf_find_function(hwclock, "set-voltage-low-0");
533 pfunc_cpu1_volt_high =
534 pmf_find_function(hwclock, "set-voltage-high-1");
535 pfunc_cpu1_volt_low =
536 pmf_find_function(hwclock, "set-voltage-low-1");
537
538 /* Check we have minimum requirements */
539 if (pfunc_cpu_getfreq == NULL || pfunc_cpu_setfreq_high == NULL ||
540 pfunc_cpu_setfreq_low == NULL || pfunc_slewing_done == NULL) {
541 pr_err("Can't find platform functions !\n");
542 rc = -ENODEV;
543 goto bail;
544 }
545
546 /* Check that we have complete sets */
547 if (pfunc_cpu0_volt_high == NULL || pfunc_cpu0_volt_low == NULL) {
548 pmf_put_function(pfunc_cpu0_volt_high);
549 pmf_put_function(pfunc_cpu0_volt_low);
550 pfunc_cpu0_volt_high = pfunc_cpu0_volt_low = NULL;
551 has_volt = 0;
552 }
553 if (!has_volt ||
554 pfunc_cpu1_volt_high == NULL || pfunc_cpu1_volt_low == NULL) {
555 pmf_put_function(pfunc_cpu1_volt_high);
556 pmf_put_function(pfunc_cpu1_volt_low);
557 pfunc_cpu1_volt_high = pfunc_cpu1_volt_low = NULL;
558 }
559
560 /* Note: The device tree also contains a "platform-set-values"
561 * function for which I haven't quite figured out the usage. It
562 * might have to be called on init and/or wakeup, I'm not too sure
563 * but things seem to work fine without it so far ...
564 */
565
566 /* Get max frequency from device-tree */
567 valp = of_get_property(cpunode, "clock-frequency", NULL);
568 if (!valp) {
569 pr_err("Can't find CPU frequency !\n");
570 rc = -ENODEV;
571 goto bail;
572 }
573
574 max_freq = (*valp)/1000;
575
576 /* Now calculate reduced frequency by using the cpuid input freq
577 * ratio. This requires 64 bits math unless we are willing to lose
578 * some precision
579 */
580 ih = *((u32 *)(eeprom + 0x10));
581 il = *((u32 *)(eeprom + 0x20));
582
583 /* Check for machines with no useful settings */
584 if (il == ih) {
585 pr_warn("No low frequency mode available on this model !\n");
586 rc = -ENODEV;
587 goto bail;
588 }
589
590 min_freq = 0;
591 if (ih != 0 && il != 0)
592 min_freq = (max_freq * il) / ih;
593
594 /* Sanity check */
595 if (min_freq >= max_freq || min_freq < 1000) {
596 pr_err("Can't calculate low frequency !\n");
597 rc = -ENXIO;
598 goto bail;
599 }
600 g5_cpu_freqs[0].frequency = max_freq;
601 g5_cpu_freqs[1].frequency = min_freq;
602
603 /* Based on a measurement on Xserve G5, rounded up. */
604 transition_latency = 10 * NSEC_PER_MSEC;
605
606 /* Set callbacks */
607 g5_switch_volt = g5_pfunc_switch_volt;
608 g5_switch_freq = g5_pfunc_switch_freq;
609 g5_query_freq = g5_pfunc_query_freq;
610
611 /* Force apply current frequency to make sure everything is in
612 * sync (voltage is right for example). Firmware may leave us with
613 * a strange setting ...
614 */
615 g5_switch_volt(CPUFREQ_HIGH);
616 msleep(10);
617 g5_pmode_cur = -1;
618 g5_switch_freq(g5_query_freq());
619
620 pr_info("Registering G5 CPU frequency driver\n");
621 pr_info("Frequency method: i2c/pfunc, Voltage method: %s\n",
622 has_volt ? "i2c/pfunc" : "none");
623 pr_info("Low: %d Mhz, High: %d Mhz, Cur: %d MHz\n",
624 g5_cpu_freqs[1].frequency/1000,
625 g5_cpu_freqs[0].frequency/1000,
626 g5_cpu_freqs[g5_pmode_cur].frequency/1000);
627
628 rc = cpufreq_register_driver(&g5_cpufreq_driver);
629 bail:
630 if (rc != 0) {
631 pmf_put_function(pfunc_cpu_getfreq);
632 pmf_put_function(pfunc_cpu_setfreq_high);
633 pmf_put_function(pfunc_cpu_setfreq_low);
634 pmf_put_function(pfunc_slewing_done);
635 pmf_put_function(pfunc_cpu0_volt_high);
636 pmf_put_function(pfunc_cpu0_volt_low);
637 pmf_put_function(pfunc_cpu1_volt_high);
638 pmf_put_function(pfunc_cpu1_volt_low);
639 }
640 of_node_put(hwclock);
641 of_node_put(cpuid);
642 of_node_put(cpunode);
643
644 return rc;
645}
646
647static int __init g5_cpufreq_init(void)
648{
649 struct device_node *cpunode;
650 int rc = 0;
651
652 /* Get first CPU node */
653 cpunode = of_cpu_device_node_get(0);
654 if (cpunode == NULL) {
655 pr_err("Can't find any CPU node\n");
656 return -ENODEV;
657 }
658
659 if (of_machine_is_compatible("PowerMac7,2") ||
660 of_machine_is_compatible("PowerMac7,3") ||
661 of_machine_is_compatible("RackMac3,1"))
662 rc = g5_pm72_cpufreq_init(cpunode);
663#ifdef CONFIG_PMAC_SMU
664 else
665 rc = g5_neo2_cpufreq_init(cpunode);
666#endif /* CONFIG_PMAC_SMU */
667
668 return rc;
669}
670
671module_init(g5_cpufreq_init);
672
673
674MODULE_DESCRIPTION("cpufreq driver for SMU & 970FX based G5 Macs");
675MODULE_LICENSE("GPL");