1 /*
2  * SMP support for power macintosh.
3  *
4  * We support both the old "powersurge" SMP architecture
5  * and the current Core99 (G4 PowerMac) machines.
6  *
7  * Note that we don't support the very first rev. of
8  * Apple/DayStar 2 CPUs board, the one with the funky
9  * watchdog. Hopefully, none of these should be there except
10  * maybe internally to Apple. I should probably still add some
11  * code to detect this card though and disable SMP. --BenH.
12  *
13  * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
14  * and Ben Herrenschmidt <benh@kernel.crashing.org>.
15  *
16  * Support for DayStar quad CPU cards
17  * Copyright (C) XLR8, Inc. 1994-2000
18  *
19  *  This program is free software; you can redistribute it and/or
20  *  modify it under the terms of the GNU General Public License
21  *  as published by the Free Software Foundation; either version
22  *  2 of the License, or (at your option) any later version.
23  */
24 #include <linux/kernel.h>
25 #include <linux/sched.h>
26 #include <linux/smp.h>
27 #include <linux/interrupt.h>
28 #include <linux/kernel_stat.h>
29 #include <linux/delay.h>
30 #include <linux/init.h>
31 #include <linux/spinlock.h>
32 #include <linux/errno.h>
33 #include <linux/hardirq.h>
34 #include <linux/cpu.h>
35 #include <linux/compiler.h>
36 
37 #include <asm/ptrace.h>
38 #include <linux/atomic.h>
39 #include <asm/code-patching.h>
40 #include <asm/irq.h>
41 #include <asm/page.h>
42 #include <asm/pgtable.h>
43 #include <asm/sections.h>
44 #include <asm/io.h>
45 #include <asm/prom.h>
46 #include <asm/smp.h>
47 #include <asm/machdep.h>
48 #include <asm/pmac_feature.h>
49 #include <asm/time.h>
50 #include <asm/mpic.h>
51 #include <asm/cacheflush.h>
52 #include <asm/keylargo.h>
53 #include <asm/pmac_low_i2c.h>
54 #include <asm/pmac_pfunc.h>
55 
56 #include "pmac.h"
57 
58 #undef DEBUG
59 
60 #ifdef DEBUG
61 #define DBG(fmt...) udbg_printf(fmt)
62 #else
63 #define DBG(fmt...)
64 #endif
65 
66 extern void __secondary_start_pmac_0(void);
67 extern int pmac_pfunc_base_install(void);
68 
69 static void (*pmac_tb_freeze)(int freeze);
70 static u64 timebase;
71 static int tb_req;
72 
73 #ifdef CONFIG_PPC_PMAC32_PSURGE
74 
75 /*
76  * Powersurge (old powermac SMP) support.
77  */
78 
79 /* Addresses for powersurge registers */
80 #define HAMMERHEAD_BASE		0xf8000000
81 #define HHEAD_CONFIG		0x90
82 #define HHEAD_SEC_INTR		0xc0
83 
84 /* register for interrupting the primary processor on the powersurge */
85 /* N.B. this is actually the ethernet ROM! */
86 #define PSURGE_PRI_INTR		0xf3019000
87 
88 /* register for storing the start address for the secondary processor */
89 /* N.B. this is the PCI config space address register for the 1st bridge */
90 #define PSURGE_START		0xf2800000
91 
92 /* Daystar/XLR8 4-CPU card */
93 #define PSURGE_QUAD_REG_ADDR	0xf8800000
94 
95 #define PSURGE_QUAD_IRQ_SET	0
96 #define PSURGE_QUAD_IRQ_CLR	1
97 #define PSURGE_QUAD_IRQ_PRIMARY	2
98 #define PSURGE_QUAD_CKSTOP_CTL	3
99 #define PSURGE_QUAD_PRIMARY_ARB	4
100 #define PSURGE_QUAD_BOARD_ID	6
101 #define PSURGE_QUAD_WHICH_CPU	7
102 #define PSURGE_QUAD_CKSTOP_RDBK	8
103 #define PSURGE_QUAD_RESET_CTL	11
104 
105 #define PSURGE_QUAD_OUT(r, v)	(out_8(quad_base + ((r) << 4) + 4, (v)))
106 #define PSURGE_QUAD_IN(r)	(in_8(quad_base + ((r) << 4) + 4) & 0x0f)
107 #define PSURGE_QUAD_BIS(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
108 #define PSURGE_QUAD_BIC(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))
109 
110 /* virtual addresses for the above */
111 static volatile u8 __iomem *hhead_base;
112 static volatile u8 __iomem *quad_base;
113 static volatile u32 __iomem *psurge_pri_intr;
114 static volatile u8 __iomem *psurge_sec_intr;
115 static volatile u32 __iomem *psurge_start;
116 
117 /* values for psurge_type */
118 #define PSURGE_NONE		-1
119 #define PSURGE_DUAL		0
120 #define PSURGE_QUAD_OKEE	1
121 #define PSURGE_QUAD_COTTON	2
122 #define PSURGE_QUAD_ICEGRASS	3
123 
124 /* what sort of powersurge board we have */
125 static int psurge_type = PSURGE_NONE;
126 
127 /* irq for secondary cpus to report */
128 static struct irq_host *psurge_host;
129 int psurge_secondary_virq;
130 
131 /*
132  * Set and clear IPIs for powersurge.
133  */
134 static inline void psurge_set_ipi(int cpu)
135 {
136 	if (psurge_type == PSURGE_NONE)
137 		return;
138 	if (cpu == 0)
139 		in_be32(psurge_pri_intr);
140 	else if (psurge_type == PSURGE_DUAL)
141 		out_8(psurge_sec_intr, 0);
142 	else
143 		PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
144 }
145 
146 static inline void psurge_clr_ipi(int cpu)
147 {
148 	if (cpu > 0) {
149 		switch(psurge_type) {
150 		case PSURGE_DUAL:
151 			out_8(psurge_sec_intr, ~0);
152 		case PSURGE_NONE:
153 			break;
154 		default:
155 			PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
156 		}
157 	}
158 }
159 
160 /*
161  * On powersurge (old SMP powermac architecture) we don't have
162  * separate IPIs for separate messages like openpic does.  Instead
163  * use the generic demux helpers
164  *  -- paulus.
165  */
166 static irqreturn_t psurge_ipi_intr(int irq, void *d)
167 {
168 	psurge_clr_ipi(smp_processor_id());
169 	smp_ipi_demux();
170 
171 	return IRQ_HANDLED;
172 }
173 
174 static void smp_psurge_cause_ipi(int cpu, unsigned long data)
175 {
176 	psurge_set_ipi(cpu);
177 }
178 
179 static int psurge_host_map(struct irq_host *h, unsigned int virq,
180 			 irq_hw_number_t hw)
181 {
182 	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_percpu_irq);
183 
184 	return 0;
185 }
186 
187 struct irq_host_ops psurge_host_ops = {
188 	.map	= psurge_host_map,
189 };
190 
191 static int psurge_secondary_ipi_init(void)
192 {
193 	int rc = -ENOMEM;
194 
195 	psurge_host = irq_alloc_host(NULL, IRQ_HOST_MAP_NOMAP, 0,
196 		&psurge_host_ops, 0);
197 
198 	if (psurge_host)
199 		psurge_secondary_virq = irq_create_direct_mapping(psurge_host);
200 
201 	if (psurge_secondary_virq)
202 		rc = request_irq(psurge_secondary_virq, psurge_ipi_intr,
203 			IRQF_DISABLED|IRQF_PERCPU, "IPI", NULL);
204 
205 	if (rc)
206 		pr_err("Failed to setup secondary cpu IPI\n");
207 
208 	return rc;
209 }
210 
211 /*
212  * Determine a quad card presence. We read the board ID register, we
213  * force the data bus to change to something else, and we read it again.
214  * It it's stable, then the register probably exist (ugh !)
215  */
216 static int __init psurge_quad_probe(void)
217 {
218 	int type;
219 	unsigned int i;
220 
221 	type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
222 	if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
223 	    || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
224 		return PSURGE_DUAL;
225 
226 	/* looks OK, try a slightly more rigorous test */
227 	/* bogus is not necessarily cacheline-aligned,
228 	   though I don't suppose that really matters.  -- paulus */
229 	for (i = 0; i < 100; i++) {
230 		volatile u32 bogus[8];
231 		bogus[(0+i)%8] = 0x00000000;
232 		bogus[(1+i)%8] = 0x55555555;
233 		bogus[(2+i)%8] = 0xFFFFFFFF;
234 		bogus[(3+i)%8] = 0xAAAAAAAA;
235 		bogus[(4+i)%8] = 0x33333333;
236 		bogus[(5+i)%8] = 0xCCCCCCCC;
237 		bogus[(6+i)%8] = 0xCCCCCCCC;
238 		bogus[(7+i)%8] = 0x33333333;
239 		wmb();
240 		asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
241 		mb();
242 		if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
243 			return PSURGE_DUAL;
244 	}
245 	return type;
246 }
247 
248 static void __init psurge_quad_init(void)
249 {
250 	int procbits;
251 
252 	if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
253 	procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
254 	if (psurge_type == PSURGE_QUAD_ICEGRASS)
255 		PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
256 	else
257 		PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
258 	mdelay(33);
259 	out_8(psurge_sec_intr, ~0);
260 	PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
261 	PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
262 	if (psurge_type != PSURGE_QUAD_ICEGRASS)
263 		PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
264 	PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
265 	mdelay(33);
266 	PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
267 	mdelay(33);
268 	PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
269 	mdelay(33);
270 }
271 
272 static int __init smp_psurge_probe(void)
273 {
274 	int i, ncpus;
275 	struct device_node *dn;
276 
277 	/* We don't do SMP on the PPC601 -- paulus */
278 	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
279 		return 1;
280 
281 	/*
282 	 * The powersurge cpu board can be used in the generation
283 	 * of powermacs that have a socket for an upgradeable cpu card,
284 	 * including the 7500, 8500, 9500, 9600.
285 	 * The device tree doesn't tell you if you have 2 cpus because
286 	 * OF doesn't know anything about the 2nd processor.
287 	 * Instead we look for magic bits in magic registers,
288 	 * in the hammerhead memory controller in the case of the
289 	 * dual-cpu powersurge board.  -- paulus.
290 	 */
291 	dn = of_find_node_by_name(NULL, "hammerhead");
292 	if (dn == NULL)
293 		return 1;
294 	of_node_put(dn);
295 
296 	hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
297 	quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
298 	psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
299 
300 	psurge_type = psurge_quad_probe();
301 	if (psurge_type != PSURGE_DUAL) {
302 		psurge_quad_init();
303 		/* All released cards using this HW design have 4 CPUs */
304 		ncpus = 4;
305 		/* No sure how timebase sync works on those, let's use SW */
306 		smp_ops->give_timebase = smp_generic_give_timebase;
307 		smp_ops->take_timebase = smp_generic_take_timebase;
308 	} else {
309 		iounmap(quad_base);
310 		if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
311 			/* not a dual-cpu card */
312 			iounmap(hhead_base);
313 			psurge_type = PSURGE_NONE;
314 			return 1;
315 		}
316 		ncpus = 2;
317 	}
318 
319 	if (psurge_secondary_ipi_init())
320 		return 1;
321 
322 	psurge_start = ioremap(PSURGE_START, 4);
323 	psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
324 
325 	/* This is necessary because OF doesn't know about the
326 	 * secondary cpu(s), and thus there aren't nodes in the
327 	 * device tree for them, and smp_setup_cpu_maps hasn't
328 	 * set their bits in cpu_present_mask.
329 	 */
330 	if (ncpus > NR_CPUS)
331 		ncpus = NR_CPUS;
332 	for (i = 1; i < ncpus ; ++i)
333 		set_cpu_present(i, true);
334 
335 	if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
336 
337 	return ncpus;
338 }
339 
340 static int __init smp_psurge_kick_cpu(int nr)
341 {
342 	unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
343 	unsigned long a, flags;
344 	int i, j;
345 
346 	/* Defining this here is evil ... but I prefer hiding that
347 	 * crap to avoid giving people ideas that they can do the
348 	 * same.
349 	 */
350 	extern volatile unsigned int cpu_callin_map[NR_CPUS];
351 
352 	/* may need to flush here if secondary bats aren't setup */
353 	for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
354 		asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
355 	asm volatile("sync");
356 
357 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
358 
359 	/* This is going to freeze the timeebase, we disable interrupts */
360 	local_irq_save(flags);
361 
362 	out_be32(psurge_start, start);
363 	mb();
364 
365 	psurge_set_ipi(nr);
366 
367 	/*
368 	 * We can't use udelay here because the timebase is now frozen.
369 	 */
370 	for (i = 0; i < 2000; ++i)
371 		asm volatile("nop" : : : "memory");
372 	psurge_clr_ipi(nr);
373 
374 	/*
375 	 * Also, because the timebase is frozen, we must not return to the
376 	 * caller which will try to do udelay's etc... Instead, we wait -here-
377 	 * for the CPU to callin.
378 	 */
379 	for (i = 0; i < 100000 && !cpu_callin_map[nr]; ++i) {
380 		for (j = 1; j < 10000; j++)
381 			asm volatile("nop" : : : "memory");
382 		asm volatile("sync" : : : "memory");
383 	}
384 	if (!cpu_callin_map[nr])
385 		goto stuck;
386 
387 	/* And we do the TB sync here too for standard dual CPU cards */
388 	if (psurge_type == PSURGE_DUAL) {
389 		while(!tb_req)
390 			barrier();
391 		tb_req = 0;
392 		mb();
393 		timebase = get_tb();
394 		mb();
395 		while (timebase)
396 			barrier();
397 		mb();
398 	}
399  stuck:
400 	/* now interrupt the secondary, restarting both TBs */
401 	if (psurge_type == PSURGE_DUAL)
402 		psurge_set_ipi(1);
403 
404 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
405 
406 	return 0;
407 }
408 
409 static struct irqaction psurge_irqaction = {
410 	.handler = psurge_ipi_intr,
411 	.flags = IRQF_DISABLED|IRQF_PERCPU,
412 	.name = "primary IPI",
413 };
414 
415 static void __init smp_psurge_setup_cpu(int cpu_nr)
416 {
417 	if (cpu_nr != 0)
418 		return;
419 
420 	/* reset the entry point so if we get another intr we won't
421 	 * try to startup again */
422 	out_be32(psurge_start, 0x100);
423 	if (setup_irq(irq_create_mapping(NULL, 30), &psurge_irqaction))
424 		printk(KERN_ERR "Couldn't get primary IPI interrupt");
425 }
426 
427 void __init smp_psurge_take_timebase(void)
428 {
429 	if (psurge_type != PSURGE_DUAL)
430 		return;
431 
432 	tb_req = 1;
433 	mb();
434 	while (!timebase)
435 		barrier();
436 	mb();
437 	set_tb(timebase >> 32, timebase & 0xffffffff);
438 	timebase = 0;
439 	mb();
440 	set_dec(tb_ticks_per_jiffy/2);
441 }
442 
443 void __init smp_psurge_give_timebase(void)
444 {
445 	/* Nothing to do here */
446 }
447 
448 /* PowerSurge-style Macs */
449 struct smp_ops_t psurge_smp_ops = {
450 	.message_pass	= NULL,	/* Use smp_muxed_ipi_message_pass */
451 	.cause_ipi	= smp_psurge_cause_ipi,
452 	.probe		= smp_psurge_probe,
453 	.kick_cpu	= smp_psurge_kick_cpu,
454 	.setup_cpu	= smp_psurge_setup_cpu,
455 	.give_timebase	= smp_psurge_give_timebase,
456 	.take_timebase	= smp_psurge_take_timebase,
457 };
458 #endif /* CONFIG_PPC_PMAC32_PSURGE */
459 
460 /*
461  * Core 99 and later support
462  */
463 
464 
465 static void smp_core99_give_timebase(void)
466 {
467 	unsigned long flags;
468 
469 	local_irq_save(flags);
470 
471 	while(!tb_req)
472 		barrier();
473 	tb_req = 0;
474 	(*pmac_tb_freeze)(1);
475 	mb();
476 	timebase = get_tb();
477 	mb();
478 	while (timebase)
479 		barrier();
480 	mb();
481 	(*pmac_tb_freeze)(0);
482 	mb();
483 
484 	local_irq_restore(flags);
485 }
486 
487 
488 static void __devinit smp_core99_take_timebase(void)
489 {
490 	unsigned long flags;
491 
492 	local_irq_save(flags);
493 
494 	tb_req = 1;
495 	mb();
496 	while (!timebase)
497 		barrier();
498 	mb();
499 	set_tb(timebase >> 32, timebase & 0xffffffff);
500 	timebase = 0;
501 	mb();
502 
503 	local_irq_restore(flags);
504 }
505 
506 #ifdef CONFIG_PPC64
507 /*
508  * G5s enable/disable the timebase via an i2c-connected clock chip.
509  */
510 static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
511 static u8 pmac_tb_pulsar_addr;
512 
513 static void smp_core99_cypress_tb_freeze(int freeze)
514 {
515 	u8 data;
516 	int rc;
517 
518 	/* Strangely, the device-tree says address is 0xd2, but darwin
519 	 * accesses 0xd0 ...
520 	 */
521 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
522 			 pmac_i2c_mode_combined);
523 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
524 			   0xd0 | pmac_i2c_read,
525 			   1, 0x81, &data, 1);
526 	if (rc != 0)
527 		goto bail;
528 
529 	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
530 
531        	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
532 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
533 			   0xd0 | pmac_i2c_write,
534 			   1, 0x81, &data, 1);
535 
536  bail:
537 	if (rc != 0) {
538 		printk("Cypress Timebase %s rc: %d\n",
539 		       freeze ? "freeze" : "unfreeze", rc);
540 		panic("Timebase freeze failed !\n");
541 	}
542 }
543 
544 
545 static void smp_core99_pulsar_tb_freeze(int freeze)
546 {
547 	u8 data;
548 	int rc;
549 
550 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
551 			 pmac_i2c_mode_combined);
552 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
553 			   pmac_tb_pulsar_addr | pmac_i2c_read,
554 			   1, 0x2e, &data, 1);
555 	if (rc != 0)
556 		goto bail;
557 
558 	data = (data & 0x88) | (freeze ? 0x11 : 0x22);
559 
560 	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
561 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
562 			   pmac_tb_pulsar_addr | pmac_i2c_write,
563 			   1, 0x2e, &data, 1);
564  bail:
565 	if (rc != 0) {
566 		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
567 		       freeze ? "freeze" : "unfreeze", rc);
568 		panic("Timebase freeze failed !\n");
569 	}
570 }
571 
572 static void __init smp_core99_setup_i2c_hwsync(int ncpus)
573 {
574 	struct device_node *cc = NULL;
575 	struct device_node *p;
576 	const char *name = NULL;
577 	const u32 *reg;
578 	int ok;
579 
580 	/* Look for the clock chip */
581 	while ((cc = of_find_node_by_name(cc, "i2c-hwclock")) != NULL) {
582 		p = of_get_parent(cc);
583 		ok = p && of_device_is_compatible(p, "uni-n-i2c");
584 		of_node_put(p);
585 		if (!ok)
586 			continue;
587 
588 		pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
589 		if (pmac_tb_clock_chip_host == NULL)
590 			continue;
591 		reg = of_get_property(cc, "reg", NULL);
592 		if (reg == NULL)
593 			continue;
594 		switch (*reg) {
595 		case 0xd2:
596 			if (of_device_is_compatible(cc,"pulsar-legacy-slewing")) {
597 				pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
598 				pmac_tb_pulsar_addr = 0xd2;
599 				name = "Pulsar";
600 			} else if (of_device_is_compatible(cc, "cy28508")) {
601 				pmac_tb_freeze = smp_core99_cypress_tb_freeze;
602 				name = "Cypress";
603 			}
604 			break;
605 		case 0xd4:
606 			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
607 			pmac_tb_pulsar_addr = 0xd4;
608 			name = "Pulsar";
609 			break;
610 		}
611 		if (pmac_tb_freeze != NULL)
612 			break;
613 	}
614 	if (pmac_tb_freeze != NULL) {
615 		/* Open i2c bus for synchronous access */
616 		if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
617 			printk(KERN_ERR "Failed top open i2c bus for clock"
618 			       " sync, fallback to software sync !\n");
619 			goto no_i2c_sync;
620 		}
621 		printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
622 		       name);
623 		return;
624 	}
625  no_i2c_sync:
626 	pmac_tb_freeze = NULL;
627 	pmac_tb_clock_chip_host = NULL;
628 }
629 
630 
631 
632 /*
633  * Newer G5s uses a platform function
634  */
635 
636 static void smp_core99_pfunc_tb_freeze(int freeze)
637 {
638 	struct device_node *cpus;
639 	struct pmf_args args;
640 
641 	cpus = of_find_node_by_path("/cpus");
642 	BUG_ON(cpus == NULL);
643 	args.count = 1;
644 	args.u[0].v = !freeze;
645 	pmf_call_function(cpus, "cpu-timebase", &args);
646 	of_node_put(cpus);
647 }
648 
649 #else /* CONFIG_PPC64 */
650 
651 /*
652  * SMP G4 use a GPIO to enable/disable the timebase.
653  */
654 
655 static unsigned int core99_tb_gpio;	/* Timebase freeze GPIO */
656 
657 static void smp_core99_gpio_tb_freeze(int freeze)
658 {
659 	if (freeze)
660 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
661 	else
662 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
663 	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
664 }
665 
666 
667 #endif /* !CONFIG_PPC64 */
668 
669 /* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
670 volatile static long int core99_l2_cache;
671 volatile static long int core99_l3_cache;
672 
673 static void __devinit core99_init_caches(int cpu)
674 {
675 #ifndef CONFIG_PPC64
676 	if (!cpu_has_feature(CPU_FTR_L2CR))
677 		return;
678 
679 	if (cpu == 0) {
680 		core99_l2_cache = _get_L2CR();
681 		printk("CPU0: L2CR is %lx\n", core99_l2_cache);
682 	} else {
683 		printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
684 		_set_L2CR(0);
685 		_set_L2CR(core99_l2_cache);
686 		printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
687 	}
688 
689 	if (!cpu_has_feature(CPU_FTR_L3CR))
690 		return;
691 
692 	if (cpu == 0){
693 		core99_l3_cache = _get_L3CR();
694 		printk("CPU0: L3CR is %lx\n", core99_l3_cache);
695 	} else {
696 		printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
697 		_set_L3CR(0);
698 		_set_L3CR(core99_l3_cache);
699 		printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
700 	}
701 #endif /* !CONFIG_PPC64 */
702 }
703 
704 static void __init smp_core99_setup(int ncpus)
705 {
706 #ifdef CONFIG_PPC64
707 
708 	/* i2c based HW sync on some G5s */
709 	if (of_machine_is_compatible("PowerMac7,2") ||
710 	    of_machine_is_compatible("PowerMac7,3") ||
711 	    of_machine_is_compatible("RackMac3,1"))
712 		smp_core99_setup_i2c_hwsync(ncpus);
713 
714 	/* pfunc based HW sync on recent G5s */
715 	if (pmac_tb_freeze == NULL) {
716 		struct device_node *cpus =
717 			of_find_node_by_path("/cpus");
718 		if (cpus &&
719 		    of_get_property(cpus, "platform-cpu-timebase", NULL)) {
720 			pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
721 			printk(KERN_INFO "Processor timebase sync using"
722 			       " platform function\n");
723 		}
724 	}
725 
726 #else /* CONFIG_PPC64 */
727 
728 	/* GPIO based HW sync on ppc32 Core99 */
729 	if (pmac_tb_freeze == NULL && !of_machine_is_compatible("MacRISC4")) {
730 		struct device_node *cpu;
731 		const u32 *tbprop = NULL;
732 
733 		core99_tb_gpio = KL_GPIO_TB_ENABLE;	/* default value */
734 		cpu = of_find_node_by_type(NULL, "cpu");
735 		if (cpu != NULL) {
736 			tbprop = of_get_property(cpu, "timebase-enable", NULL);
737 			if (tbprop)
738 				core99_tb_gpio = *tbprop;
739 			of_node_put(cpu);
740 		}
741 		pmac_tb_freeze = smp_core99_gpio_tb_freeze;
742 		printk(KERN_INFO "Processor timebase sync using"
743 		       " GPIO 0x%02x\n", core99_tb_gpio);
744 	}
745 
746 #endif /* CONFIG_PPC64 */
747 
748 	/* No timebase sync, fallback to software */
749 	if (pmac_tb_freeze == NULL) {
750 		smp_ops->give_timebase = smp_generic_give_timebase;
751 		smp_ops->take_timebase = smp_generic_take_timebase;
752 		printk(KERN_INFO "Processor timebase sync using software\n");
753 	}
754 
755 #ifndef CONFIG_PPC64
756 	{
757 		int i;
758 
759 		/* XXX should get this from reg properties */
760 		for (i = 1; i < ncpus; ++i)
761 			set_hard_smp_processor_id(i, i);
762 	}
763 #endif
764 
765 	/* 32 bits SMP can't NAP */
766 	if (!of_machine_is_compatible("MacRISC4"))
767 		powersave_nap = 0;
768 }
769 
770 static int __init smp_core99_probe(void)
771 {
772 	struct device_node *cpus;
773 	int ncpus = 0;
774 
775 	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
776 
777 	/* Count CPUs in the device-tree */
778        	for (cpus = NULL; (cpus = of_find_node_by_type(cpus, "cpu")) != NULL;)
779 	       	++ncpus;
780 
781 	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
782 
783 	/* Nothing more to do if less than 2 of them */
784 	if (ncpus <= 1)
785 		return 1;
786 
787 	/* We need to perform some early initialisations before we can start
788 	 * setting up SMP as we are running before initcalls
789 	 */
790 	pmac_pfunc_base_install();
791 	pmac_i2c_init();
792 
793 	/* Setup various bits like timebase sync method, ability to nap, ... */
794 	smp_core99_setup(ncpus);
795 
796 	/* Install IPIs */
797 	mpic_request_ipis();
798 
799 	/* Collect l2cr and l3cr values from CPU 0 */
800 	core99_init_caches(0);
801 
802 	return ncpus;
803 }
804 
805 static int __devinit smp_core99_kick_cpu(int nr)
806 {
807 	unsigned int save_vector;
808 	unsigned long target, flags;
809 	unsigned int *vector = (unsigned int *)(PAGE_OFFSET+0x100);
810 
811 	if (nr < 0 || nr > 3)
812 		return -ENOENT;
813 
814 	if (ppc_md.progress)
815 		ppc_md.progress("smp_core99_kick_cpu", 0x346);
816 
817 	local_irq_save(flags);
818 
819 	/* Save reset vector */
820 	save_vector = *vector;
821 
822 	/* Setup fake reset vector that does
823 	 *   b __secondary_start_pmac_0 + nr*8
824 	 */
825 	target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
826 	patch_branch(vector, target, BRANCH_SET_LINK);
827 
828 	/* Put some life in our friend */
829 	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
830 
831 	/* FIXME: We wait a bit for the CPU to take the exception, I should
832 	 * instead wait for the entry code to set something for me. Well,
833 	 * ideally, all that crap will be done in prom.c and the CPU left
834 	 * in a RAM-based wait loop like CHRP.
835 	 */
836 	mdelay(1);
837 
838 	/* Restore our exception vector */
839 	*vector = save_vector;
840 	flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
841 
842 	local_irq_restore(flags);
843 	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
844 
845 	return 0;
846 }
847 
848 static void __devinit smp_core99_setup_cpu(int cpu_nr)
849 {
850 	/* Setup L2/L3 */
851 	if (cpu_nr != 0)
852 		core99_init_caches(cpu_nr);
853 
854 	/* Setup openpic */
855 	mpic_setup_this_cpu();
856 }
857 
858 #ifdef CONFIG_PPC64
859 #ifdef CONFIG_HOTPLUG_CPU
860 static int smp_core99_cpu_notify(struct notifier_block *self,
861 				 unsigned long action, void *hcpu)
862 {
863 	int rc;
864 
865 	switch(action) {
866 	case CPU_UP_PREPARE:
867 	case CPU_UP_PREPARE_FROZEN:
868 		/* Open i2c bus if it was used for tb sync */
869 		if (pmac_tb_clock_chip_host) {
870 			rc = pmac_i2c_open(pmac_tb_clock_chip_host, 1);
871 			if (rc) {
872 				pr_err("Failed to open i2c bus for time sync\n");
873 				return notifier_from_errno(rc);
874 			}
875 		}
876 		break;
877 	case CPU_ONLINE:
878 	case CPU_UP_CANCELED:
879 		/* Close i2c bus if it was used for tb sync */
880 		if (pmac_tb_clock_chip_host)
881 			pmac_i2c_close(pmac_tb_clock_chip_host);
882 		break;
883 	default:
884 		break;
885 	}
886 	return NOTIFY_OK;
887 }
888 
889 static struct notifier_block __cpuinitdata smp_core99_cpu_nb = {
890 	.notifier_call	= smp_core99_cpu_notify,
891 };
892 #endif /* CONFIG_HOTPLUG_CPU */
893 
894 static void __init smp_core99_bringup_done(void)
895 {
896 	extern void g5_phy_disable_cpu1(void);
897 
898 	/* Close i2c bus if it was used for tb sync */
899 	if (pmac_tb_clock_chip_host)
900 		pmac_i2c_close(pmac_tb_clock_chip_host);
901 
902 	/* If we didn't start the second CPU, we must take
903 	 * it off the bus.
904 	 */
905 	if (of_machine_is_compatible("MacRISC4") &&
906 	    num_online_cpus() < 2) {
907 		set_cpu_present(1, false);
908 		g5_phy_disable_cpu1();
909 	}
910 #ifdef CONFIG_HOTPLUG_CPU
911 	register_cpu_notifier(&smp_core99_cpu_nb);
912 #endif
913 
914 	if (ppc_md.progress)
915 		ppc_md.progress("smp_core99_bringup_done", 0x349);
916 }
917 #endif /* CONFIG_PPC64 */
918 
919 #ifdef CONFIG_HOTPLUG_CPU
920 
921 static int smp_core99_cpu_disable(void)
922 {
923 	int rc = generic_cpu_disable();
924 	if (rc)
925 		return rc;
926 
927 	mpic_cpu_set_priority(0xf);
928 
929 	return 0;
930 }
931 
932 #ifdef CONFIG_PPC32
933 
934 static void pmac_cpu_die(void)
935 {
936 	int cpu = smp_processor_id();
937 
938 	local_irq_disable();
939 	idle_task_exit();
940 	pr_debug("CPU%d offline\n", cpu);
941 	generic_set_cpu_dead(cpu);
942 	smp_wmb();
943 	mb();
944 	low_cpu_die();
945 }
946 
947 #else /* CONFIG_PPC32 */
948 
949 static void pmac_cpu_die(void)
950 {
951 	int cpu = smp_processor_id();
952 
953 	local_irq_disable();
954 	idle_task_exit();
955 
956 	/*
957 	 * turn off as much as possible, we'll be
958 	 * kicked out as this will only be invoked
959 	 * on core99 platforms for now ...
960 	 */
961 
962 	printk(KERN_INFO "CPU#%d offline\n", cpu);
963 	generic_set_cpu_dead(cpu);
964 	smp_wmb();
965 
966 	/*
967 	 * Re-enable interrupts. The NAP code needs to enable them
968 	 * anyways, do it now so we deal with the case where one already
969 	 * happened while soft-disabled.
970 	 * We shouldn't get any external interrupts, only decrementer, and the
971 	 * decrementer handler is safe for use on offline CPUs
972 	 */
973 	local_irq_enable();
974 
975 	while (1) {
976 		/* let's not take timer interrupts too often ... */
977 		set_dec(0x7fffffff);
978 
979 		/* Enter NAP mode */
980 		power4_idle();
981 	}
982 }
983 
984 #endif /* else CONFIG_PPC32 */
985 #endif /* CONFIG_HOTPLUG_CPU */
986 
987 /* Core99 Macs (dual G4s and G5s) */
988 struct smp_ops_t core99_smp_ops = {
989 	.message_pass	= smp_mpic_message_pass,
990 	.probe		= smp_core99_probe,
991 #ifdef CONFIG_PPC64
992 	.bringup_done	= smp_core99_bringup_done,
993 #endif
994 	.kick_cpu	= smp_core99_kick_cpu,
995 	.setup_cpu	= smp_core99_setup_cpu,
996 	.give_timebase	= smp_core99_give_timebase,
997 	.take_timebase	= smp_core99_take_timebase,
998 #if defined(CONFIG_HOTPLUG_CPU)
999 	.cpu_disable	= smp_core99_cpu_disable,
1000 	.cpu_die	= generic_cpu_die,
1001 #endif
1002 };
1003 
1004 void __init pmac_setup_smp(void)
1005 {
1006 	struct device_node *np;
1007 
1008 	/* Check for Core99 */
1009 	np = of_find_node_by_name(NULL, "uni-n");
1010 	if (!np)
1011 		np = of_find_node_by_name(NULL, "u3");
1012 	if (!np)
1013 		np = of_find_node_by_name(NULL, "u4");
1014 	if (np) {
1015 		of_node_put(np);
1016 		smp_ops = &core99_smp_ops;
1017 	}
1018 #ifdef CONFIG_PPC_PMAC32_PSURGE
1019 	else {
1020 		/* We have to set bits in cpu_possible_mask here since the
1021 		 * secondary CPU(s) aren't in the device tree. Various
1022 		 * things won't be initialized for CPUs not in the possible
1023 		 * map, so we really need to fix it up here.
1024 		 */
1025 		int cpu;
1026 
1027 		for (cpu = 1; cpu < 4 && cpu < NR_CPUS; ++cpu)
1028 			set_cpu_possible(cpu, true);
1029 		smp_ops = &psurge_smp_ops;
1030 	}
1031 #endif /* CONFIG_PPC_PMAC32_PSURGE */
1032 
1033 #ifdef CONFIG_HOTPLUG_CPU
1034 	ppc_md.cpu_die = pmac_cpu_die;
1035 #endif
1036 }
1037 
1038 
1039