1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * SMP support for power macintosh.
4  *
5  * We support both the old "powersurge" SMP architecture
6  * and the current Core99 (G4 PowerMac) machines.
7  *
8  * Note that we don't support the very first rev. of
9  * Apple/DayStar 2 CPUs board, the one with the funky
10  * watchdog. Hopefully, none of these should be there except
11  * maybe internally to Apple. I should probably still add some
12  * code to detect this card though and disable SMP. --BenH.
13  *
14  * Support Macintosh G4 SMP by Troy Benjegerdes (hozer@drgw.net)
15  * and Ben Herrenschmidt <benh@kernel.crashing.org>.
16  *
17  * Support for DayStar quad CPU cards
18  * Copyright (C) XLR8, Inc. 1994-2000
19  */
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
22 #include <linux/sched/hotplug.h>
23 #include <linux/smp.h>
24 #include <linux/interrupt.h>
25 #include <linux/kernel_stat.h>
26 #include <linux/delay.h>
27 #include <linux/init.h>
28 #include <linux/spinlock.h>
29 #include <linux/errno.h>
30 #include <linux/hardirq.h>
31 #include <linux/cpu.h>
32 #include <linux/compiler.h>
33 #include <linux/pgtable.h>
34 
35 #include <asm/ptrace.h>
36 #include <linux/atomic.h>
37 #include <asm/code-patching.h>
38 #include <asm/irq.h>
39 #include <asm/page.h>
40 #include <asm/sections.h>
41 #include <asm/io.h>
42 #include <asm/prom.h>
43 #include <asm/smp.h>
44 #include <asm/machdep.h>
45 #include <asm/pmac_feature.h>
46 #include <asm/time.h>
47 #include <asm/mpic.h>
48 #include <asm/cacheflush.h>
49 #include <asm/keylargo.h>
50 #include <asm/pmac_low_i2c.h>
51 #include <asm/pmac_pfunc.h>
52 #include <asm/inst.h>
53 
54 #include "pmac.h"
55 
56 #undef DEBUG
57 
58 #ifdef DEBUG
59 #define DBG(fmt...) udbg_printf(fmt)
60 #else
61 #define DBG(fmt...)
62 #endif
63 
64 extern void __secondary_start_pmac_0(void);
65 
66 static void (*pmac_tb_freeze)(int freeze);
67 static u64 timebase;
68 static int tb_req;
69 
70 #ifdef CONFIG_PPC_PMAC32_PSURGE
71 
72 /*
73  * Powersurge (old powermac SMP) support.
74  */
75 
76 /* Addresses for powersurge registers */
77 #define HAMMERHEAD_BASE		0xf8000000
78 #define HHEAD_CONFIG		0x90
79 #define HHEAD_SEC_INTR		0xc0
80 
81 /* register for interrupting the primary processor on the powersurge */
82 /* N.B. this is actually the ethernet ROM! */
83 #define PSURGE_PRI_INTR		0xf3019000
84 
85 /* register for storing the start address for the secondary processor */
86 /* N.B. this is the PCI config space address register for the 1st bridge */
87 #define PSURGE_START		0xf2800000
88 
89 /* Daystar/XLR8 4-CPU card */
90 #define PSURGE_QUAD_REG_ADDR	0xf8800000
91 
92 #define PSURGE_QUAD_IRQ_SET	0
93 #define PSURGE_QUAD_IRQ_CLR	1
94 #define PSURGE_QUAD_IRQ_PRIMARY	2
95 #define PSURGE_QUAD_CKSTOP_CTL	3
96 #define PSURGE_QUAD_PRIMARY_ARB	4
97 #define PSURGE_QUAD_BOARD_ID	6
98 #define PSURGE_QUAD_WHICH_CPU	7
99 #define PSURGE_QUAD_CKSTOP_RDBK	8
100 #define PSURGE_QUAD_RESET_CTL	11
101 
102 #define PSURGE_QUAD_OUT(r, v)	(out_8(quad_base + ((r) << 4) + 4, (v)))
103 #define PSURGE_QUAD_IN(r)	(in_8(quad_base + ((r) << 4) + 4) & 0x0f)
104 #define PSURGE_QUAD_BIS(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
105 #define PSURGE_QUAD_BIC(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))
106 
107 /* virtual addresses for the above */
108 static volatile u8 __iomem *hhead_base;
109 static volatile u8 __iomem *quad_base;
110 static volatile u32 __iomem *psurge_pri_intr;
111 static volatile u8 __iomem *psurge_sec_intr;
112 static volatile u32 __iomem *psurge_start;
113 
114 /* values for psurge_type */
115 #define PSURGE_NONE		-1
116 #define PSURGE_DUAL		0
117 #define PSURGE_QUAD_OKEE	1
118 #define PSURGE_QUAD_COTTON	2
119 #define PSURGE_QUAD_ICEGRASS	3
120 
121 /* what sort of powersurge board we have */
122 static int psurge_type = PSURGE_NONE;
123 
124 /* irq for secondary cpus to report */
125 static struct irq_domain *psurge_host;
126 int psurge_secondary_virq;
127 
128 /*
129  * Set and clear IPIs for powersurge.
130  */
131 static inline void psurge_set_ipi(int cpu)
132 {
133 	if (psurge_type == PSURGE_NONE)
134 		return;
135 	if (cpu == 0)
136 		in_be32(psurge_pri_intr);
137 	else if (psurge_type == PSURGE_DUAL)
138 		out_8(psurge_sec_intr, 0);
139 	else
140 		PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
141 }
142 
143 static inline void psurge_clr_ipi(int cpu)
144 {
145 	if (cpu > 0) {
146 		switch(psurge_type) {
147 		case PSURGE_DUAL:
148 			out_8(psurge_sec_intr, ~0);
149 		case PSURGE_NONE:
150 			break;
151 		default:
152 			PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
153 		}
154 	}
155 }
156 
157 /*
158  * On powersurge (old SMP powermac architecture) we don't have
159  * separate IPIs for separate messages like openpic does.  Instead
160  * use the generic demux helpers
161  *  -- paulus.
162  */
163 static irqreturn_t psurge_ipi_intr(int irq, void *d)
164 {
165 	psurge_clr_ipi(smp_processor_id());
166 	smp_ipi_demux();
167 
168 	return IRQ_HANDLED;
169 }
170 
171 static void smp_psurge_cause_ipi(int cpu)
172 {
173 	psurge_set_ipi(cpu);
174 }
175 
176 static int psurge_host_map(struct irq_domain *h, unsigned int virq,
177 			 irq_hw_number_t hw)
178 {
179 	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_percpu_irq);
180 
181 	return 0;
182 }
183 
184 static const struct irq_domain_ops psurge_host_ops = {
185 	.map	= psurge_host_map,
186 };
187 
188 static int psurge_secondary_ipi_init(void)
189 {
190 	int rc = -ENOMEM;
191 
192 	psurge_host = irq_domain_add_nomap(NULL, ~0, &psurge_host_ops, NULL);
193 
194 	if (psurge_host)
195 		psurge_secondary_virq = irq_create_direct_mapping(psurge_host);
196 
197 	if (psurge_secondary_virq)
198 		rc = request_irq(psurge_secondary_virq, psurge_ipi_intr,
199 			IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL);
200 
201 	if (rc)
202 		pr_err("Failed to setup secondary cpu IPI\n");
203 
204 	return rc;
205 }
206 
207 /*
208  * Determine a quad card presence. We read the board ID register, we
209  * force the data bus to change to something else, and we read it again.
210  * It it's stable, then the register probably exist (ugh !)
211  */
212 static int __init psurge_quad_probe(void)
213 {
214 	int type;
215 	unsigned int i;
216 
217 	type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
218 	if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
219 	    || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
220 		return PSURGE_DUAL;
221 
222 	/* looks OK, try a slightly more rigorous test */
223 	/* bogus is not necessarily cacheline-aligned,
224 	   though I don't suppose that really matters.  -- paulus */
225 	for (i = 0; i < 100; i++) {
226 		volatile u32 bogus[8];
227 		bogus[(0+i)%8] = 0x00000000;
228 		bogus[(1+i)%8] = 0x55555555;
229 		bogus[(2+i)%8] = 0xFFFFFFFF;
230 		bogus[(3+i)%8] = 0xAAAAAAAA;
231 		bogus[(4+i)%8] = 0x33333333;
232 		bogus[(5+i)%8] = 0xCCCCCCCC;
233 		bogus[(6+i)%8] = 0xCCCCCCCC;
234 		bogus[(7+i)%8] = 0x33333333;
235 		wmb();
236 		asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
237 		mb();
238 		if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
239 			return PSURGE_DUAL;
240 	}
241 	return type;
242 }
243 
244 static void __init psurge_quad_init(void)
245 {
246 	int procbits;
247 
248 	if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
249 	procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
250 	if (psurge_type == PSURGE_QUAD_ICEGRASS)
251 		PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
252 	else
253 		PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
254 	mdelay(33);
255 	out_8(psurge_sec_intr, ~0);
256 	PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
257 	PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
258 	if (psurge_type != PSURGE_QUAD_ICEGRASS)
259 		PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
260 	PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
261 	mdelay(33);
262 	PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
263 	mdelay(33);
264 	PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
265 	mdelay(33);
266 }
267 
268 static void __init smp_psurge_probe(void)
269 {
270 	int i, ncpus;
271 	struct device_node *dn;
272 
273 	/* We don't do SMP on the PPC601 -- paulus */
274 	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
275 		return;
276 
277 	/*
278 	 * The powersurge cpu board can be used in the generation
279 	 * of powermacs that have a socket for an upgradeable cpu card,
280 	 * including the 7500, 8500, 9500, 9600.
281 	 * The device tree doesn't tell you if you have 2 cpus because
282 	 * OF doesn't know anything about the 2nd processor.
283 	 * Instead we look for magic bits in magic registers,
284 	 * in the hammerhead memory controller in the case of the
285 	 * dual-cpu powersurge board.  -- paulus.
286 	 */
287 	dn = of_find_node_by_name(NULL, "hammerhead");
288 	if (dn == NULL)
289 		return;
290 	of_node_put(dn);
291 
292 	hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
293 	quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
294 	psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
295 
296 	psurge_type = psurge_quad_probe();
297 	if (psurge_type != PSURGE_DUAL) {
298 		psurge_quad_init();
299 		/* All released cards using this HW design have 4 CPUs */
300 		ncpus = 4;
301 		/* No sure how timebase sync works on those, let's use SW */
302 		smp_ops->give_timebase = smp_generic_give_timebase;
303 		smp_ops->take_timebase = smp_generic_take_timebase;
304 	} else {
305 		iounmap(quad_base);
306 		if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
307 			/* not a dual-cpu card */
308 			iounmap(hhead_base);
309 			psurge_type = PSURGE_NONE;
310 			return;
311 		}
312 		ncpus = 2;
313 	}
314 
315 	if (psurge_secondary_ipi_init())
316 		return;
317 
318 	psurge_start = ioremap(PSURGE_START, 4);
319 	psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
320 
321 	/* This is necessary because OF doesn't know about the
322 	 * secondary cpu(s), and thus there aren't nodes in the
323 	 * device tree for them, and smp_setup_cpu_maps hasn't
324 	 * set their bits in cpu_present_mask.
325 	 */
326 	if (ncpus > NR_CPUS)
327 		ncpus = NR_CPUS;
328 	for (i = 1; i < ncpus ; ++i)
329 		set_cpu_present(i, true);
330 
331 	if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
332 }
333 
334 static int __init smp_psurge_kick_cpu(int nr)
335 {
336 	unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
337 	unsigned long a, flags;
338 	int i, j;
339 
340 	/* Defining this here is evil ... but I prefer hiding that
341 	 * crap to avoid giving people ideas that they can do the
342 	 * same.
343 	 */
344 	extern volatile unsigned int cpu_callin_map[NR_CPUS];
345 
346 	/* may need to flush here if secondary bats aren't setup */
347 	for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
348 		asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
349 	asm volatile("sync");
350 
351 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
352 
353 	/* This is going to freeze the timeebase, we disable interrupts */
354 	local_irq_save(flags);
355 
356 	out_be32(psurge_start, start);
357 	mb();
358 
359 	psurge_set_ipi(nr);
360 
361 	/*
362 	 * We can't use udelay here because the timebase is now frozen.
363 	 */
364 	for (i = 0; i < 2000; ++i)
365 		asm volatile("nop" : : : "memory");
366 	psurge_clr_ipi(nr);
367 
368 	/*
369 	 * Also, because the timebase is frozen, we must not return to the
370 	 * caller which will try to do udelay's etc... Instead, we wait -here-
371 	 * for the CPU to callin.
372 	 */
373 	for (i = 0; i < 100000 && !cpu_callin_map[nr]; ++i) {
374 		for (j = 1; j < 10000; j++)
375 			asm volatile("nop" : : : "memory");
376 		asm volatile("sync" : : : "memory");
377 	}
378 	if (!cpu_callin_map[nr])
379 		goto stuck;
380 
381 	/* And we do the TB sync here too for standard dual CPU cards */
382 	if (psurge_type == PSURGE_DUAL) {
383 		while(!tb_req)
384 			barrier();
385 		tb_req = 0;
386 		mb();
387 		timebase = get_tb();
388 		mb();
389 		while (timebase)
390 			barrier();
391 		mb();
392 	}
393  stuck:
394 	/* now interrupt the secondary, restarting both TBs */
395 	if (psurge_type == PSURGE_DUAL)
396 		psurge_set_ipi(1);
397 
398 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
399 
400 	return 0;
401 }
402 
403 static void __init smp_psurge_setup_cpu(int cpu_nr)
404 {
405 	unsigned long flags = IRQF_PERCPU | IRQF_NO_THREAD;
406 	int irq;
407 
408 	if (cpu_nr != 0 || !psurge_start)
409 		return;
410 
411 	/* reset the entry point so if we get another intr we won't
412 	 * try to startup again */
413 	out_be32(psurge_start, 0x100);
414 	irq = irq_create_mapping(NULL, 30);
415 	if (request_irq(irq, psurge_ipi_intr, flags, "primary IPI", NULL))
416 		printk(KERN_ERR "Couldn't get primary IPI interrupt");
417 }
418 
419 void __init smp_psurge_take_timebase(void)
420 {
421 	if (psurge_type != PSURGE_DUAL)
422 		return;
423 
424 	tb_req = 1;
425 	mb();
426 	while (!timebase)
427 		barrier();
428 	mb();
429 	set_tb(timebase >> 32, timebase & 0xffffffff);
430 	timebase = 0;
431 	mb();
432 	set_dec(tb_ticks_per_jiffy/2);
433 }
434 
435 void __init smp_psurge_give_timebase(void)
436 {
437 	/* Nothing to do here */
438 }
439 
440 /* PowerSurge-style Macs */
441 struct smp_ops_t psurge_smp_ops = {
442 	.message_pass	= NULL,	/* Use smp_muxed_ipi_message_pass */
443 	.cause_ipi	= smp_psurge_cause_ipi,
444 	.cause_nmi_ipi	= NULL,
445 	.probe		= smp_psurge_probe,
446 	.kick_cpu	= smp_psurge_kick_cpu,
447 	.setup_cpu	= smp_psurge_setup_cpu,
448 	.give_timebase	= smp_psurge_give_timebase,
449 	.take_timebase	= smp_psurge_take_timebase,
450 };
451 #endif /* CONFIG_PPC_PMAC32_PSURGE */
452 
453 /*
454  * Core 99 and later support
455  */
456 
457 
458 static void smp_core99_give_timebase(void)
459 {
460 	unsigned long flags;
461 
462 	local_irq_save(flags);
463 
464 	while(!tb_req)
465 		barrier();
466 	tb_req = 0;
467 	(*pmac_tb_freeze)(1);
468 	mb();
469 	timebase = get_tb();
470 	mb();
471 	while (timebase)
472 		barrier();
473 	mb();
474 	(*pmac_tb_freeze)(0);
475 	mb();
476 
477 	local_irq_restore(flags);
478 }
479 
480 
481 static void smp_core99_take_timebase(void)
482 {
483 	unsigned long flags;
484 
485 	local_irq_save(flags);
486 
487 	tb_req = 1;
488 	mb();
489 	while (!timebase)
490 		barrier();
491 	mb();
492 	set_tb(timebase >> 32, timebase & 0xffffffff);
493 	timebase = 0;
494 	mb();
495 
496 	local_irq_restore(flags);
497 }
498 
499 #ifdef CONFIG_PPC64
500 /*
501  * G5s enable/disable the timebase via an i2c-connected clock chip.
502  */
503 static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
504 static u8 pmac_tb_pulsar_addr;
505 
506 static void smp_core99_cypress_tb_freeze(int freeze)
507 {
508 	u8 data;
509 	int rc;
510 
511 	/* Strangely, the device-tree says address is 0xd2, but darwin
512 	 * accesses 0xd0 ...
513 	 */
514 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
515 			 pmac_i2c_mode_combined);
516 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
517 			   0xd0 | pmac_i2c_read,
518 			   1, 0x81, &data, 1);
519 	if (rc != 0)
520 		goto bail;
521 
522 	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
523 
524        	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
525 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
526 			   0xd0 | pmac_i2c_write,
527 			   1, 0x81, &data, 1);
528 
529  bail:
530 	if (rc != 0) {
531 		printk("Cypress Timebase %s rc: %d\n",
532 		       freeze ? "freeze" : "unfreeze", rc);
533 		panic("Timebase freeze failed !\n");
534 	}
535 }
536 
537 
538 static void smp_core99_pulsar_tb_freeze(int freeze)
539 {
540 	u8 data;
541 	int rc;
542 
543 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
544 			 pmac_i2c_mode_combined);
545 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
546 			   pmac_tb_pulsar_addr | pmac_i2c_read,
547 			   1, 0x2e, &data, 1);
548 	if (rc != 0)
549 		goto bail;
550 
551 	data = (data & 0x88) | (freeze ? 0x11 : 0x22);
552 
553 	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
554 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
555 			   pmac_tb_pulsar_addr | pmac_i2c_write,
556 			   1, 0x2e, &data, 1);
557  bail:
558 	if (rc != 0) {
559 		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
560 		       freeze ? "freeze" : "unfreeze", rc);
561 		panic("Timebase freeze failed !\n");
562 	}
563 }
564 
565 static void __init smp_core99_setup_i2c_hwsync(int ncpus)
566 {
567 	struct device_node *cc = NULL;
568 	struct device_node *p;
569 	const char *name = NULL;
570 	const u32 *reg;
571 	int ok;
572 
573 	/* Look for the clock chip */
574 	for_each_node_by_name(cc, "i2c-hwclock") {
575 		p = of_get_parent(cc);
576 		ok = p && of_device_is_compatible(p, "uni-n-i2c");
577 		of_node_put(p);
578 		if (!ok)
579 			continue;
580 
581 		pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
582 		if (pmac_tb_clock_chip_host == NULL)
583 			continue;
584 		reg = of_get_property(cc, "reg", NULL);
585 		if (reg == NULL)
586 			continue;
587 		switch (*reg) {
588 		case 0xd2:
589 			if (of_device_is_compatible(cc,"pulsar-legacy-slewing")) {
590 				pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
591 				pmac_tb_pulsar_addr = 0xd2;
592 				name = "Pulsar";
593 			} else if (of_device_is_compatible(cc, "cy28508")) {
594 				pmac_tb_freeze = smp_core99_cypress_tb_freeze;
595 				name = "Cypress";
596 			}
597 			break;
598 		case 0xd4:
599 			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
600 			pmac_tb_pulsar_addr = 0xd4;
601 			name = "Pulsar";
602 			break;
603 		}
604 		if (pmac_tb_freeze != NULL)
605 			break;
606 	}
607 	if (pmac_tb_freeze != NULL) {
608 		/* Open i2c bus for synchronous access */
609 		if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
610 			printk(KERN_ERR "Failed top open i2c bus for clock"
611 			       " sync, fallback to software sync !\n");
612 			goto no_i2c_sync;
613 		}
614 		printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
615 		       name);
616 		return;
617 	}
618  no_i2c_sync:
619 	pmac_tb_freeze = NULL;
620 	pmac_tb_clock_chip_host = NULL;
621 }
622 
623 
624 
625 /*
626  * Newer G5s uses a platform function
627  */
628 
629 static void smp_core99_pfunc_tb_freeze(int freeze)
630 {
631 	struct device_node *cpus;
632 	struct pmf_args args;
633 
634 	cpus = of_find_node_by_path("/cpus");
635 	BUG_ON(cpus == NULL);
636 	args.count = 1;
637 	args.u[0].v = !freeze;
638 	pmf_call_function(cpus, "cpu-timebase", &args);
639 	of_node_put(cpus);
640 }
641 
642 #else /* CONFIG_PPC64 */
643 
644 /*
645  * SMP G4 use a GPIO to enable/disable the timebase.
646  */
647 
648 static unsigned int core99_tb_gpio;	/* Timebase freeze GPIO */
649 
650 static void smp_core99_gpio_tb_freeze(int freeze)
651 {
652 	if (freeze)
653 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
654 	else
655 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
656 	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
657 }
658 
659 
660 #endif /* !CONFIG_PPC64 */
661 
662 static void core99_init_caches(int cpu)
663 {
664 #ifndef CONFIG_PPC64
665 	/* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
666 	static long int core99_l2_cache;
667 	static long int core99_l3_cache;
668 
669 	if (!cpu_has_feature(CPU_FTR_L2CR))
670 		return;
671 
672 	if (cpu == 0) {
673 		core99_l2_cache = _get_L2CR();
674 		printk("CPU0: L2CR is %lx\n", core99_l2_cache);
675 	} else {
676 		printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
677 		_set_L2CR(0);
678 		_set_L2CR(core99_l2_cache);
679 		printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
680 	}
681 
682 	if (!cpu_has_feature(CPU_FTR_L3CR))
683 		return;
684 
685 	if (cpu == 0){
686 		core99_l3_cache = _get_L3CR();
687 		printk("CPU0: L3CR is %lx\n", core99_l3_cache);
688 	} else {
689 		printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
690 		_set_L3CR(0);
691 		_set_L3CR(core99_l3_cache);
692 		printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
693 	}
694 #endif /* !CONFIG_PPC64 */
695 }
696 
697 static void __init smp_core99_setup(int ncpus)
698 {
699 #ifdef CONFIG_PPC64
700 
701 	/* i2c based HW sync on some G5s */
702 	if (of_machine_is_compatible("PowerMac7,2") ||
703 	    of_machine_is_compatible("PowerMac7,3") ||
704 	    of_machine_is_compatible("RackMac3,1"))
705 		smp_core99_setup_i2c_hwsync(ncpus);
706 
707 	/* pfunc based HW sync on recent G5s */
708 	if (pmac_tb_freeze == NULL) {
709 		struct device_node *cpus =
710 			of_find_node_by_path("/cpus");
711 		if (cpus &&
712 		    of_get_property(cpus, "platform-cpu-timebase", NULL)) {
713 			pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
714 			printk(KERN_INFO "Processor timebase sync using"
715 			       " platform function\n");
716 		}
717 	}
718 
719 #else /* CONFIG_PPC64 */
720 
721 	/* GPIO based HW sync on ppc32 Core99 */
722 	if (pmac_tb_freeze == NULL && !of_machine_is_compatible("MacRISC4")) {
723 		struct device_node *cpu;
724 		const u32 *tbprop = NULL;
725 
726 		core99_tb_gpio = KL_GPIO_TB_ENABLE;	/* default value */
727 		cpu = of_find_node_by_type(NULL, "cpu");
728 		if (cpu != NULL) {
729 			tbprop = of_get_property(cpu, "timebase-enable", NULL);
730 			if (tbprop)
731 				core99_tb_gpio = *tbprop;
732 			of_node_put(cpu);
733 		}
734 		pmac_tb_freeze = smp_core99_gpio_tb_freeze;
735 		printk(KERN_INFO "Processor timebase sync using"
736 		       " GPIO 0x%02x\n", core99_tb_gpio);
737 	}
738 
739 #endif /* CONFIG_PPC64 */
740 
741 	/* No timebase sync, fallback to software */
742 	if (pmac_tb_freeze == NULL) {
743 		smp_ops->give_timebase = smp_generic_give_timebase;
744 		smp_ops->take_timebase = smp_generic_take_timebase;
745 		printk(KERN_INFO "Processor timebase sync using software\n");
746 	}
747 
748 #ifndef CONFIG_PPC64
749 	{
750 		int i;
751 
752 		/* XXX should get this from reg properties */
753 		for (i = 1; i < ncpus; ++i)
754 			set_hard_smp_processor_id(i, i);
755 	}
756 #endif
757 
758 	/* 32 bits SMP can't NAP */
759 	if (!of_machine_is_compatible("MacRISC4"))
760 		powersave_nap = 0;
761 }
762 
763 static void __init smp_core99_probe(void)
764 {
765 	struct device_node *cpus;
766 	int ncpus = 0;
767 
768 	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
769 
770 	/* Count CPUs in the device-tree */
771 	for_each_node_by_type(cpus, "cpu")
772 		++ncpus;
773 
774 	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
775 
776 	/* Nothing more to do if less than 2 of them */
777 	if (ncpus <= 1)
778 		return;
779 
780 	/* We need to perform some early initialisations before we can start
781 	 * setting up SMP as we are running before initcalls
782 	 */
783 	pmac_pfunc_base_install();
784 	pmac_i2c_init();
785 
786 	/* Setup various bits like timebase sync method, ability to nap, ... */
787 	smp_core99_setup(ncpus);
788 
789 	/* Install IPIs */
790 	mpic_request_ipis();
791 
792 	/* Collect l2cr and l3cr values from CPU 0 */
793 	core99_init_caches(0);
794 }
795 
796 static int smp_core99_kick_cpu(int nr)
797 {
798 	unsigned int save_vector;
799 	unsigned long target, flags;
800 	unsigned int *vector = (unsigned int *)(PAGE_OFFSET+0x100);
801 
802 	if (nr < 0 || nr > 3)
803 		return -ENOENT;
804 
805 	if (ppc_md.progress)
806 		ppc_md.progress("smp_core99_kick_cpu", 0x346);
807 
808 	local_irq_save(flags);
809 
810 	/* Save reset vector */
811 	save_vector = *vector;
812 
813 	/* Setup fake reset vector that does
814 	 *   b __secondary_start_pmac_0 + nr*8
815 	 */
816 	target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
817 	patch_branch((struct ppc_inst *)vector, target, BRANCH_SET_LINK);
818 
819 	/* Put some life in our friend */
820 	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
821 
822 	/* FIXME: We wait a bit for the CPU to take the exception, I should
823 	 * instead wait for the entry code to set something for me. Well,
824 	 * ideally, all that crap will be done in prom.c and the CPU left
825 	 * in a RAM-based wait loop like CHRP.
826 	 */
827 	mdelay(1);
828 
829 	/* Restore our exception vector */
830 	patch_instruction((struct ppc_inst *)vector, ppc_inst(save_vector));
831 
832 	local_irq_restore(flags);
833 	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
834 
835 	return 0;
836 }
837 
838 static void smp_core99_setup_cpu(int cpu_nr)
839 {
840 	/* Setup L2/L3 */
841 	if (cpu_nr != 0)
842 		core99_init_caches(cpu_nr);
843 
844 	/* Setup openpic */
845 	mpic_setup_this_cpu();
846 }
847 
848 #ifdef CONFIG_PPC64
849 #ifdef CONFIG_HOTPLUG_CPU
850 static unsigned int smp_core99_host_open;
851 
852 static int smp_core99_cpu_prepare(unsigned int cpu)
853 {
854 	int rc;
855 
856 	/* Open i2c bus if it was used for tb sync */
857 	if (pmac_tb_clock_chip_host && !smp_core99_host_open) {
858 		rc = pmac_i2c_open(pmac_tb_clock_chip_host, 1);
859 		if (rc) {
860 			pr_err("Failed to open i2c bus for time sync\n");
861 			return notifier_from_errno(rc);
862 		}
863 		smp_core99_host_open = 1;
864 	}
865 	return 0;
866 }
867 
868 static int smp_core99_cpu_online(unsigned int cpu)
869 {
870 	/* Close i2c bus if it was used for tb sync */
871 	if (pmac_tb_clock_chip_host && smp_core99_host_open) {
872 		pmac_i2c_close(pmac_tb_clock_chip_host);
873 		smp_core99_host_open = 0;
874 	}
875 	return 0;
876 }
877 #endif /* CONFIG_HOTPLUG_CPU */
878 
879 static void __init smp_core99_bringup_done(void)
880 {
881 	extern void g5_phy_disable_cpu1(void);
882 
883 	/* Close i2c bus if it was used for tb sync */
884 	if (pmac_tb_clock_chip_host)
885 		pmac_i2c_close(pmac_tb_clock_chip_host);
886 
887 	/* If we didn't start the second CPU, we must take
888 	 * it off the bus.
889 	 */
890 	if (of_machine_is_compatible("MacRISC4") &&
891 	    num_online_cpus() < 2) {
892 		set_cpu_present(1, false);
893 		g5_phy_disable_cpu1();
894 	}
895 #ifdef CONFIG_HOTPLUG_CPU
896 	cpuhp_setup_state_nocalls(CPUHP_POWERPC_PMAC_PREPARE,
897 				  "powerpc/pmac:prepare", smp_core99_cpu_prepare,
898 				  NULL);
899 	cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "powerpc/pmac:online",
900 				  smp_core99_cpu_online, NULL);
901 #endif
902 
903 	if (ppc_md.progress)
904 		ppc_md.progress("smp_core99_bringup_done", 0x349);
905 }
906 #endif /* CONFIG_PPC64 */
907 
908 #ifdef CONFIG_HOTPLUG_CPU
909 
910 static int smp_core99_cpu_disable(void)
911 {
912 	int rc = generic_cpu_disable();
913 	if (rc)
914 		return rc;
915 
916 	mpic_cpu_set_priority(0xf);
917 
918 	return 0;
919 }
920 
921 #ifdef CONFIG_PPC32
922 
923 static void pmac_cpu_die(void)
924 {
925 	int cpu = smp_processor_id();
926 
927 	local_irq_disable();
928 	idle_task_exit();
929 	pr_debug("CPU%d offline\n", cpu);
930 	generic_set_cpu_dead(cpu);
931 	smp_wmb();
932 	mb();
933 	low_cpu_die();
934 }
935 
936 #else /* CONFIG_PPC32 */
937 
938 static void pmac_cpu_die(void)
939 {
940 	int cpu = smp_processor_id();
941 
942 	local_irq_disable();
943 	idle_task_exit();
944 
945 	/*
946 	 * turn off as much as possible, we'll be
947 	 * kicked out as this will only be invoked
948 	 * on core99 platforms for now ...
949 	 */
950 
951 	printk(KERN_INFO "CPU#%d offline\n", cpu);
952 	generic_set_cpu_dead(cpu);
953 	smp_wmb();
954 
955 	/*
956 	 * Re-enable interrupts. The NAP code needs to enable them
957 	 * anyways, do it now so we deal with the case where one already
958 	 * happened while soft-disabled.
959 	 * We shouldn't get any external interrupts, only decrementer, and the
960 	 * decrementer handler is safe for use on offline CPUs
961 	 */
962 	local_irq_enable();
963 
964 	while (1) {
965 		/* let's not take timer interrupts too often ... */
966 		set_dec(0x7fffffff);
967 
968 		/* Enter NAP mode */
969 		power4_idle();
970 	}
971 }
972 
973 #endif /* else CONFIG_PPC32 */
974 #endif /* CONFIG_HOTPLUG_CPU */
975 
976 /* Core99 Macs (dual G4s and G5s) */
977 static struct smp_ops_t core99_smp_ops = {
978 	.message_pass	= smp_mpic_message_pass,
979 	.probe		= smp_core99_probe,
980 #ifdef CONFIG_PPC64
981 	.bringup_done	= smp_core99_bringup_done,
982 #endif
983 	.kick_cpu	= smp_core99_kick_cpu,
984 	.setup_cpu	= smp_core99_setup_cpu,
985 	.give_timebase	= smp_core99_give_timebase,
986 	.take_timebase	= smp_core99_take_timebase,
987 #if defined(CONFIG_HOTPLUG_CPU)
988 	.cpu_disable	= smp_core99_cpu_disable,
989 	.cpu_die	= generic_cpu_die,
990 #endif
991 };
992 
993 void __init pmac_setup_smp(void)
994 {
995 	struct device_node *np;
996 
997 	/* Check for Core99 */
998 	np = of_find_node_by_name(NULL, "uni-n");
999 	if (!np)
1000 		np = of_find_node_by_name(NULL, "u3");
1001 	if (!np)
1002 		np = of_find_node_by_name(NULL, "u4");
1003 	if (np) {
1004 		of_node_put(np);
1005 		smp_ops = &core99_smp_ops;
1006 	}
1007 #ifdef CONFIG_PPC_PMAC32_PSURGE
1008 	else {
1009 		/* We have to set bits in cpu_possible_mask here since the
1010 		 * secondary CPU(s) aren't in the device tree. Various
1011 		 * things won't be initialized for CPUs not in the possible
1012 		 * map, so we really need to fix it up here.
1013 		 */
1014 		int cpu;
1015 
1016 		for (cpu = 1; cpu < 4 && cpu < NR_CPUS; ++cpu)
1017 			set_cpu_possible(cpu, true);
1018 		smp_ops = &psurge_smp_ops;
1019 	}
1020 #endif /* CONFIG_PPC_PMAC32_PSURGE */
1021 
1022 #ifdef CONFIG_HOTPLUG_CPU
1023 	ppc_md.cpu_die = pmac_cpu_die;
1024 #endif
1025 }
1026 
1027 
1028