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 
34 #include <asm/ptrace.h>
35 #include <linux/atomic.h>
36 #include <asm/code-patching.h>
37 #include <asm/irq.h>
38 #include <asm/page.h>
39 #include <asm/pgtable.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 
53 #include "pmac.h"
54 
55 #undef DEBUG
56 
57 #ifdef DEBUG
58 #define DBG(fmt...) udbg_printf(fmt)
59 #else
60 #define DBG(fmt...)
61 #endif
62 
63 extern void __secondary_start_pmac_0(void);
64 
65 static void (*pmac_tb_freeze)(int freeze);
66 static u64 timebase;
67 static int tb_req;
68 
69 #ifdef CONFIG_PPC_PMAC32_PSURGE
70 
71 /*
72  * Powersurge (old powermac SMP) support.
73  */
74 
75 /* Addresses for powersurge registers */
76 #define HAMMERHEAD_BASE		0xf8000000
77 #define HHEAD_CONFIG		0x90
78 #define HHEAD_SEC_INTR		0xc0
79 
80 /* register for interrupting the primary processor on the powersurge */
81 /* N.B. this is actually the ethernet ROM! */
82 #define PSURGE_PRI_INTR		0xf3019000
83 
84 /* register for storing the start address for the secondary processor */
85 /* N.B. this is the PCI config space address register for the 1st bridge */
86 #define PSURGE_START		0xf2800000
87 
88 /* Daystar/XLR8 4-CPU card */
89 #define PSURGE_QUAD_REG_ADDR	0xf8800000
90 
91 #define PSURGE_QUAD_IRQ_SET	0
92 #define PSURGE_QUAD_IRQ_CLR	1
93 #define PSURGE_QUAD_IRQ_PRIMARY	2
94 #define PSURGE_QUAD_CKSTOP_CTL	3
95 #define PSURGE_QUAD_PRIMARY_ARB	4
96 #define PSURGE_QUAD_BOARD_ID	6
97 #define PSURGE_QUAD_WHICH_CPU	7
98 #define PSURGE_QUAD_CKSTOP_RDBK	8
99 #define PSURGE_QUAD_RESET_CTL	11
100 
101 #define PSURGE_QUAD_OUT(r, v)	(out_8(quad_base + ((r) << 4) + 4, (v)))
102 #define PSURGE_QUAD_IN(r)	(in_8(quad_base + ((r) << 4) + 4) & 0x0f)
103 #define PSURGE_QUAD_BIS(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) | (v)))
104 #define PSURGE_QUAD_BIC(r, v)	(PSURGE_QUAD_OUT((r), PSURGE_QUAD_IN(r) & ~(v)))
105 
106 /* virtual addresses for the above */
107 static volatile u8 __iomem *hhead_base;
108 static volatile u8 __iomem *quad_base;
109 static volatile u32 __iomem *psurge_pri_intr;
110 static volatile u8 __iomem *psurge_sec_intr;
111 static volatile u32 __iomem *psurge_start;
112 
113 /* values for psurge_type */
114 #define PSURGE_NONE		-1
115 #define PSURGE_DUAL		0
116 #define PSURGE_QUAD_OKEE	1
117 #define PSURGE_QUAD_COTTON	2
118 #define PSURGE_QUAD_ICEGRASS	3
119 
120 /* what sort of powersurge board we have */
121 static int psurge_type = PSURGE_NONE;
122 
123 /* irq for secondary cpus to report */
124 static struct irq_domain *psurge_host;
125 int psurge_secondary_virq;
126 
127 /*
128  * Set and clear IPIs for powersurge.
129  */
130 static inline void psurge_set_ipi(int cpu)
131 {
132 	if (psurge_type == PSURGE_NONE)
133 		return;
134 	if (cpu == 0)
135 		in_be32(psurge_pri_intr);
136 	else if (psurge_type == PSURGE_DUAL)
137 		out_8(psurge_sec_intr, 0);
138 	else
139 		PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_SET, 1 << cpu);
140 }
141 
142 static inline void psurge_clr_ipi(int cpu)
143 {
144 	if (cpu > 0) {
145 		switch(psurge_type) {
146 		case PSURGE_DUAL:
147 			out_8(psurge_sec_intr, ~0);
148 		case PSURGE_NONE:
149 			break;
150 		default:
151 			PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, 1 << cpu);
152 		}
153 	}
154 }
155 
156 /*
157  * On powersurge (old SMP powermac architecture) we don't have
158  * separate IPIs for separate messages like openpic does.  Instead
159  * use the generic demux helpers
160  *  -- paulus.
161  */
162 static irqreturn_t psurge_ipi_intr(int irq, void *d)
163 {
164 	psurge_clr_ipi(smp_processor_id());
165 	smp_ipi_demux();
166 
167 	return IRQ_HANDLED;
168 }
169 
170 static void smp_psurge_cause_ipi(int cpu)
171 {
172 	psurge_set_ipi(cpu);
173 }
174 
175 static int psurge_host_map(struct irq_domain *h, unsigned int virq,
176 			 irq_hw_number_t hw)
177 {
178 	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_percpu_irq);
179 
180 	return 0;
181 }
182 
183 static const struct irq_domain_ops psurge_host_ops = {
184 	.map	= psurge_host_map,
185 };
186 
187 static int psurge_secondary_ipi_init(void)
188 {
189 	int rc = -ENOMEM;
190 
191 	psurge_host = irq_domain_add_nomap(NULL, ~0, &psurge_host_ops, NULL);
192 
193 	if (psurge_host)
194 		psurge_secondary_virq = irq_create_direct_mapping(psurge_host);
195 
196 	if (psurge_secondary_virq)
197 		rc = request_irq(psurge_secondary_virq, psurge_ipi_intr,
198 			IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL);
199 
200 	if (rc)
201 		pr_err("Failed to setup secondary cpu IPI\n");
202 
203 	return rc;
204 }
205 
206 /*
207  * Determine a quad card presence. We read the board ID register, we
208  * force the data bus to change to something else, and we read it again.
209  * It it's stable, then the register probably exist (ugh !)
210  */
211 static int __init psurge_quad_probe(void)
212 {
213 	int type;
214 	unsigned int i;
215 
216 	type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
217 	if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
218 	    || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
219 		return PSURGE_DUAL;
220 
221 	/* looks OK, try a slightly more rigorous test */
222 	/* bogus is not necessarily cacheline-aligned,
223 	   though I don't suppose that really matters.  -- paulus */
224 	for (i = 0; i < 100; i++) {
225 		volatile u32 bogus[8];
226 		bogus[(0+i)%8] = 0x00000000;
227 		bogus[(1+i)%8] = 0x55555555;
228 		bogus[(2+i)%8] = 0xFFFFFFFF;
229 		bogus[(3+i)%8] = 0xAAAAAAAA;
230 		bogus[(4+i)%8] = 0x33333333;
231 		bogus[(5+i)%8] = 0xCCCCCCCC;
232 		bogus[(6+i)%8] = 0xCCCCCCCC;
233 		bogus[(7+i)%8] = 0x33333333;
234 		wmb();
235 		asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
236 		mb();
237 		if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
238 			return PSURGE_DUAL;
239 	}
240 	return type;
241 }
242 
243 static void __init psurge_quad_init(void)
244 {
245 	int procbits;
246 
247 	if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
248 	procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
249 	if (psurge_type == PSURGE_QUAD_ICEGRASS)
250 		PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
251 	else
252 		PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
253 	mdelay(33);
254 	out_8(psurge_sec_intr, ~0);
255 	PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
256 	PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
257 	if (psurge_type != PSURGE_QUAD_ICEGRASS)
258 		PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
259 	PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
260 	mdelay(33);
261 	PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
262 	mdelay(33);
263 	PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
264 	mdelay(33);
265 }
266 
267 static void __init smp_psurge_probe(void)
268 {
269 	int i, ncpus;
270 	struct device_node *dn;
271 
272 	/* We don't do SMP on the PPC601 -- paulus */
273 	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
274 		return;
275 
276 	/*
277 	 * The powersurge cpu board can be used in the generation
278 	 * of powermacs that have a socket for an upgradeable cpu card,
279 	 * including the 7500, 8500, 9500, 9600.
280 	 * The device tree doesn't tell you if you have 2 cpus because
281 	 * OF doesn't know anything about the 2nd processor.
282 	 * Instead we look for magic bits in magic registers,
283 	 * in the hammerhead memory controller in the case of the
284 	 * dual-cpu powersurge board.  -- paulus.
285 	 */
286 	dn = of_find_node_by_name(NULL, "hammerhead");
287 	if (dn == NULL)
288 		return;
289 	of_node_put(dn);
290 
291 	hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
292 	quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
293 	psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
294 
295 	psurge_type = psurge_quad_probe();
296 	if (psurge_type != PSURGE_DUAL) {
297 		psurge_quad_init();
298 		/* All released cards using this HW design have 4 CPUs */
299 		ncpus = 4;
300 		/* No sure how timebase sync works on those, let's use SW */
301 		smp_ops->give_timebase = smp_generic_give_timebase;
302 		smp_ops->take_timebase = smp_generic_take_timebase;
303 	} else {
304 		iounmap(quad_base);
305 		if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
306 			/* not a dual-cpu card */
307 			iounmap(hhead_base);
308 			psurge_type = PSURGE_NONE;
309 			return;
310 		}
311 		ncpus = 2;
312 	}
313 
314 	if (psurge_secondary_ipi_init())
315 		return;
316 
317 	psurge_start = ioremap(PSURGE_START, 4);
318 	psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
319 
320 	/* This is necessary because OF doesn't know about the
321 	 * secondary cpu(s), and thus there aren't nodes in the
322 	 * device tree for them, and smp_setup_cpu_maps hasn't
323 	 * set their bits in cpu_present_mask.
324 	 */
325 	if (ncpus > NR_CPUS)
326 		ncpus = NR_CPUS;
327 	for (i = 1; i < ncpus ; ++i)
328 		set_cpu_present(i, true);
329 
330 	if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
331 }
332 
333 static int __init smp_psurge_kick_cpu(int nr)
334 {
335 	unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
336 	unsigned long a, flags;
337 	int i, j;
338 
339 	/* Defining this here is evil ... but I prefer hiding that
340 	 * crap to avoid giving people ideas that they can do the
341 	 * same.
342 	 */
343 	extern volatile unsigned int cpu_callin_map[NR_CPUS];
344 
345 	/* may need to flush here if secondary bats aren't setup */
346 	for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
347 		asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
348 	asm volatile("sync");
349 
350 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
351 
352 	/* This is going to freeze the timeebase, we disable interrupts */
353 	local_irq_save(flags);
354 
355 	out_be32(psurge_start, start);
356 	mb();
357 
358 	psurge_set_ipi(nr);
359 
360 	/*
361 	 * We can't use udelay here because the timebase is now frozen.
362 	 */
363 	for (i = 0; i < 2000; ++i)
364 		asm volatile("nop" : : : "memory");
365 	psurge_clr_ipi(nr);
366 
367 	/*
368 	 * Also, because the timebase is frozen, we must not return to the
369 	 * caller which will try to do udelay's etc... Instead, we wait -here-
370 	 * for the CPU to callin.
371 	 */
372 	for (i = 0; i < 100000 && !cpu_callin_map[nr]; ++i) {
373 		for (j = 1; j < 10000; j++)
374 			asm volatile("nop" : : : "memory");
375 		asm volatile("sync" : : : "memory");
376 	}
377 	if (!cpu_callin_map[nr])
378 		goto stuck;
379 
380 	/* And we do the TB sync here too for standard dual CPU cards */
381 	if (psurge_type == PSURGE_DUAL) {
382 		while(!tb_req)
383 			barrier();
384 		tb_req = 0;
385 		mb();
386 		timebase = get_tb();
387 		mb();
388 		while (timebase)
389 			barrier();
390 		mb();
391 	}
392  stuck:
393 	/* now interrupt the secondary, restarting both TBs */
394 	if (psurge_type == PSURGE_DUAL)
395 		psurge_set_ipi(1);
396 
397 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
398 
399 	return 0;
400 }
401 
402 static struct irqaction psurge_irqaction = {
403 	.handler = psurge_ipi_intr,
404 	.flags = IRQF_PERCPU | IRQF_NO_THREAD,
405 	.name = "primary IPI",
406 };
407 
408 static void __init smp_psurge_setup_cpu(int cpu_nr)
409 {
410 	if (cpu_nr != 0 || !psurge_start)
411 		return;
412 
413 	/* reset the entry point so if we get another intr we won't
414 	 * try to startup again */
415 	out_be32(psurge_start, 0x100);
416 	if (setup_irq(irq_create_mapping(NULL, 30), &psurge_irqaction))
417 		printk(KERN_ERR "Couldn't get primary IPI interrupt");
418 }
419 
420 void __init smp_psurge_take_timebase(void)
421 {
422 	if (psurge_type != PSURGE_DUAL)
423 		return;
424 
425 	tb_req = 1;
426 	mb();
427 	while (!timebase)
428 		barrier();
429 	mb();
430 	set_tb(timebase >> 32, timebase & 0xffffffff);
431 	timebase = 0;
432 	mb();
433 	set_dec(tb_ticks_per_jiffy/2);
434 }
435 
436 void __init smp_psurge_give_timebase(void)
437 {
438 	/* Nothing to do here */
439 }
440 
441 /* PowerSurge-style Macs */
442 struct smp_ops_t psurge_smp_ops = {
443 	.message_pass	= NULL,	/* Use smp_muxed_ipi_message_pass */
444 	.cause_ipi	= smp_psurge_cause_ipi,
445 	.cause_nmi_ipi	= NULL,
446 	.probe		= smp_psurge_probe,
447 	.kick_cpu	= smp_psurge_kick_cpu,
448 	.setup_cpu	= smp_psurge_setup_cpu,
449 	.give_timebase	= smp_psurge_give_timebase,
450 	.take_timebase	= smp_psurge_take_timebase,
451 };
452 #endif /* CONFIG_PPC_PMAC32_PSURGE */
453 
454 /*
455  * Core 99 and later support
456  */
457 
458 
459 static void smp_core99_give_timebase(void)
460 {
461 	unsigned long flags;
462 
463 	local_irq_save(flags);
464 
465 	while(!tb_req)
466 		barrier();
467 	tb_req = 0;
468 	(*pmac_tb_freeze)(1);
469 	mb();
470 	timebase = get_tb();
471 	mb();
472 	while (timebase)
473 		barrier();
474 	mb();
475 	(*pmac_tb_freeze)(0);
476 	mb();
477 
478 	local_irq_restore(flags);
479 }
480 
481 
482 static void smp_core99_take_timebase(void)
483 {
484 	unsigned long flags;
485 
486 	local_irq_save(flags);
487 
488 	tb_req = 1;
489 	mb();
490 	while (!timebase)
491 		barrier();
492 	mb();
493 	set_tb(timebase >> 32, timebase & 0xffffffff);
494 	timebase = 0;
495 	mb();
496 
497 	local_irq_restore(flags);
498 }
499 
500 #ifdef CONFIG_PPC64
501 /*
502  * G5s enable/disable the timebase via an i2c-connected clock chip.
503  */
504 static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
505 static u8 pmac_tb_pulsar_addr;
506 
507 static void smp_core99_cypress_tb_freeze(int freeze)
508 {
509 	u8 data;
510 	int rc;
511 
512 	/* Strangely, the device-tree says address is 0xd2, but darwin
513 	 * accesses 0xd0 ...
514 	 */
515 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
516 			 pmac_i2c_mode_combined);
517 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
518 			   0xd0 | pmac_i2c_read,
519 			   1, 0x81, &data, 1);
520 	if (rc != 0)
521 		goto bail;
522 
523 	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
524 
525        	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
526 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
527 			   0xd0 | pmac_i2c_write,
528 			   1, 0x81, &data, 1);
529 
530  bail:
531 	if (rc != 0) {
532 		printk("Cypress Timebase %s rc: %d\n",
533 		       freeze ? "freeze" : "unfreeze", rc);
534 		panic("Timebase freeze failed !\n");
535 	}
536 }
537 
538 
539 static void smp_core99_pulsar_tb_freeze(int freeze)
540 {
541 	u8 data;
542 	int rc;
543 
544 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
545 			 pmac_i2c_mode_combined);
546 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
547 			   pmac_tb_pulsar_addr | pmac_i2c_read,
548 			   1, 0x2e, &data, 1);
549 	if (rc != 0)
550 		goto bail;
551 
552 	data = (data & 0x88) | (freeze ? 0x11 : 0x22);
553 
554 	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
555 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
556 			   pmac_tb_pulsar_addr | pmac_i2c_write,
557 			   1, 0x2e, &data, 1);
558  bail:
559 	if (rc != 0) {
560 		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
561 		       freeze ? "freeze" : "unfreeze", rc);
562 		panic("Timebase freeze failed !\n");
563 	}
564 }
565 
566 static void __init smp_core99_setup_i2c_hwsync(int ncpus)
567 {
568 	struct device_node *cc = NULL;
569 	struct device_node *p;
570 	const char *name = NULL;
571 	const u32 *reg;
572 	int ok;
573 
574 	/* Look for the clock chip */
575 	for_each_node_by_name(cc, "i2c-hwclock") {
576 		p = of_get_parent(cc);
577 		ok = p && of_device_is_compatible(p, "uni-n-i2c");
578 		of_node_put(p);
579 		if (!ok)
580 			continue;
581 
582 		pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
583 		if (pmac_tb_clock_chip_host == NULL)
584 			continue;
585 		reg = of_get_property(cc, "reg", NULL);
586 		if (reg == NULL)
587 			continue;
588 		switch (*reg) {
589 		case 0xd2:
590 			if (of_device_is_compatible(cc,"pulsar-legacy-slewing")) {
591 				pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
592 				pmac_tb_pulsar_addr = 0xd2;
593 				name = "Pulsar";
594 			} else if (of_device_is_compatible(cc, "cy28508")) {
595 				pmac_tb_freeze = smp_core99_cypress_tb_freeze;
596 				name = "Cypress";
597 			}
598 			break;
599 		case 0xd4:
600 			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
601 			pmac_tb_pulsar_addr = 0xd4;
602 			name = "Pulsar";
603 			break;
604 		}
605 		if (pmac_tb_freeze != NULL)
606 			break;
607 	}
608 	if (pmac_tb_freeze != NULL) {
609 		/* Open i2c bus for synchronous access */
610 		if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
611 			printk(KERN_ERR "Failed top open i2c bus for clock"
612 			       " sync, fallback to software sync !\n");
613 			goto no_i2c_sync;
614 		}
615 		printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
616 		       name);
617 		return;
618 	}
619  no_i2c_sync:
620 	pmac_tb_freeze = NULL;
621 	pmac_tb_clock_chip_host = NULL;
622 }
623 
624 
625 
626 /*
627  * Newer G5s uses a platform function
628  */
629 
630 static void smp_core99_pfunc_tb_freeze(int freeze)
631 {
632 	struct device_node *cpus;
633 	struct pmf_args args;
634 
635 	cpus = of_find_node_by_path("/cpus");
636 	BUG_ON(cpus == NULL);
637 	args.count = 1;
638 	args.u[0].v = !freeze;
639 	pmf_call_function(cpus, "cpu-timebase", &args);
640 	of_node_put(cpus);
641 }
642 
643 #else /* CONFIG_PPC64 */
644 
645 /*
646  * SMP G4 use a GPIO to enable/disable the timebase.
647  */
648 
649 static unsigned int core99_tb_gpio;	/* Timebase freeze GPIO */
650 
651 static void smp_core99_gpio_tb_freeze(int freeze)
652 {
653 	if (freeze)
654 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
655 	else
656 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
657 	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
658 }
659 
660 
661 #endif /* !CONFIG_PPC64 */
662 
663 /* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
664 volatile static long int core99_l2_cache;
665 volatile static long int core99_l3_cache;
666 
667 static void core99_init_caches(int cpu)
668 {
669 #ifndef CONFIG_PPC64
670 	if (!cpu_has_feature(CPU_FTR_L2CR))
671 		return;
672 
673 	if (cpu == 0) {
674 		core99_l2_cache = _get_L2CR();
675 		printk("CPU0: L2CR is %lx\n", core99_l2_cache);
676 	} else {
677 		printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
678 		_set_L2CR(0);
679 		_set_L2CR(core99_l2_cache);
680 		printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
681 	}
682 
683 	if (!cpu_has_feature(CPU_FTR_L3CR))
684 		return;
685 
686 	if (cpu == 0){
687 		core99_l3_cache = _get_L3CR();
688 		printk("CPU0: L3CR is %lx\n", core99_l3_cache);
689 	} else {
690 		printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
691 		_set_L3CR(0);
692 		_set_L3CR(core99_l3_cache);
693 		printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
694 	}
695 #endif /* !CONFIG_PPC64 */
696 }
697 
698 static void __init smp_core99_setup(int ncpus)
699 {
700 #ifdef CONFIG_PPC64
701 
702 	/* i2c based HW sync on some G5s */
703 	if (of_machine_is_compatible("PowerMac7,2") ||
704 	    of_machine_is_compatible("PowerMac7,3") ||
705 	    of_machine_is_compatible("RackMac3,1"))
706 		smp_core99_setup_i2c_hwsync(ncpus);
707 
708 	/* pfunc based HW sync on recent G5s */
709 	if (pmac_tb_freeze == NULL) {
710 		struct device_node *cpus =
711 			of_find_node_by_path("/cpus");
712 		if (cpus &&
713 		    of_get_property(cpus, "platform-cpu-timebase", NULL)) {
714 			pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
715 			printk(KERN_INFO "Processor timebase sync using"
716 			       " platform function\n");
717 		}
718 	}
719 
720 #else /* CONFIG_PPC64 */
721 
722 	/* GPIO based HW sync on ppc32 Core99 */
723 	if (pmac_tb_freeze == NULL && !of_machine_is_compatible("MacRISC4")) {
724 		struct device_node *cpu;
725 		const u32 *tbprop = NULL;
726 
727 		core99_tb_gpio = KL_GPIO_TB_ENABLE;	/* default value */
728 		cpu = of_find_node_by_type(NULL, "cpu");
729 		if (cpu != NULL) {
730 			tbprop = of_get_property(cpu, "timebase-enable", NULL);
731 			if (tbprop)
732 				core99_tb_gpio = *tbprop;
733 			of_node_put(cpu);
734 		}
735 		pmac_tb_freeze = smp_core99_gpio_tb_freeze;
736 		printk(KERN_INFO "Processor timebase sync using"
737 		       " GPIO 0x%02x\n", core99_tb_gpio);
738 	}
739 
740 #endif /* CONFIG_PPC64 */
741 
742 	/* No timebase sync, fallback to software */
743 	if (pmac_tb_freeze == NULL) {
744 		smp_ops->give_timebase = smp_generic_give_timebase;
745 		smp_ops->take_timebase = smp_generic_take_timebase;
746 		printk(KERN_INFO "Processor timebase sync using software\n");
747 	}
748 
749 #ifndef CONFIG_PPC64
750 	{
751 		int i;
752 
753 		/* XXX should get this from reg properties */
754 		for (i = 1; i < ncpus; ++i)
755 			set_hard_smp_processor_id(i, i);
756 	}
757 #endif
758 
759 	/* 32 bits SMP can't NAP */
760 	if (!of_machine_is_compatible("MacRISC4"))
761 		powersave_nap = 0;
762 }
763 
764 static void __init smp_core99_probe(void)
765 {
766 	struct device_node *cpus;
767 	int ncpus = 0;
768 
769 	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
770 
771 	/* Count CPUs in the device-tree */
772 	for_each_node_by_type(cpus, "cpu")
773 		++ncpus;
774 
775 	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
776 
777 	/* Nothing more to do if less than 2 of them */
778 	if (ncpus <= 1)
779 		return;
780 
781 	/* We need to perform some early initialisations before we can start
782 	 * setting up SMP as we are running before initcalls
783 	 */
784 	pmac_pfunc_base_install();
785 	pmac_i2c_init();
786 
787 	/* Setup various bits like timebase sync method, ability to nap, ... */
788 	smp_core99_setup(ncpus);
789 
790 	/* Install IPIs */
791 	mpic_request_ipis();
792 
793 	/* Collect l2cr and l3cr values from CPU 0 */
794 	core99_init_caches(0);
795 }
796 
797 static int smp_core99_kick_cpu(int nr)
798 {
799 	unsigned int save_vector;
800 	unsigned long target, flags;
801 	unsigned int *vector = (unsigned int *)(PAGE_OFFSET+0x100);
802 
803 	if (nr < 0 || nr > 3)
804 		return -ENOENT;
805 
806 	if (ppc_md.progress)
807 		ppc_md.progress("smp_core99_kick_cpu", 0x346);
808 
809 	local_irq_save(flags);
810 
811 	/* Save reset vector */
812 	save_vector = *vector;
813 
814 	/* Setup fake reset vector that does
815 	 *   b __secondary_start_pmac_0 + nr*8
816 	 */
817 	target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
818 	patch_branch(vector, target, BRANCH_SET_LINK);
819 
820 	/* Put some life in our friend */
821 	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
822 
823 	/* FIXME: We wait a bit for the CPU to take the exception, I should
824 	 * instead wait for the entry code to set something for me. Well,
825 	 * ideally, all that crap will be done in prom.c and the CPU left
826 	 * in a RAM-based wait loop like CHRP.
827 	 */
828 	mdelay(1);
829 
830 	/* Restore our exception vector */
831 	patch_instruction(vector, save_vector);
832 
833 	local_irq_restore(flags);
834 	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
835 
836 	return 0;
837 }
838 
839 static void smp_core99_setup_cpu(int cpu_nr)
840 {
841 	/* Setup L2/L3 */
842 	if (cpu_nr != 0)
843 		core99_init_caches(cpu_nr);
844 
845 	/* Setup openpic */
846 	mpic_setup_this_cpu();
847 }
848 
849 #ifdef CONFIG_PPC64
850 #ifdef CONFIG_HOTPLUG_CPU
851 static unsigned int smp_core99_host_open;
852 
853 static int smp_core99_cpu_prepare(unsigned int cpu)
854 {
855 	int rc;
856 
857 	/* Open i2c bus if it was used for tb sync */
858 	if (pmac_tb_clock_chip_host && !smp_core99_host_open) {
859 		rc = pmac_i2c_open(pmac_tb_clock_chip_host, 1);
860 		if (rc) {
861 			pr_err("Failed to open i2c bus for time sync\n");
862 			return notifier_from_errno(rc);
863 		}
864 		smp_core99_host_open = 1;
865 	}
866 	return 0;
867 }
868 
869 static int smp_core99_cpu_online(unsigned int cpu)
870 {
871 	/* Close i2c bus if it was used for tb sync */
872 	if (pmac_tb_clock_chip_host && smp_core99_host_open) {
873 		pmac_i2c_close(pmac_tb_clock_chip_host);
874 		smp_core99_host_open = 0;
875 	}
876 	return 0;
877 }
878 #endif /* CONFIG_HOTPLUG_CPU */
879 
880 static void __init smp_core99_bringup_done(void)
881 {
882 	extern void g5_phy_disable_cpu1(void);
883 
884 	/* Close i2c bus if it was used for tb sync */
885 	if (pmac_tb_clock_chip_host)
886 		pmac_i2c_close(pmac_tb_clock_chip_host);
887 
888 	/* If we didn't start the second CPU, we must take
889 	 * it off the bus.
890 	 */
891 	if (of_machine_is_compatible("MacRISC4") &&
892 	    num_online_cpus() < 2) {
893 		set_cpu_present(1, false);
894 		g5_phy_disable_cpu1();
895 	}
896 #ifdef CONFIG_HOTPLUG_CPU
897 	cpuhp_setup_state_nocalls(CPUHP_POWERPC_PMAC_PREPARE,
898 				  "powerpc/pmac:prepare", smp_core99_cpu_prepare,
899 				  NULL);
900 	cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "powerpc/pmac:online",
901 				  smp_core99_cpu_online, NULL);
902 #endif
903 
904 	if (ppc_md.progress)
905 		ppc_md.progress("smp_core99_bringup_done", 0x349);
906 }
907 #endif /* CONFIG_PPC64 */
908 
909 #ifdef CONFIG_HOTPLUG_CPU
910 
911 static int smp_core99_cpu_disable(void)
912 {
913 	int rc = generic_cpu_disable();
914 	if (rc)
915 		return rc;
916 
917 	mpic_cpu_set_priority(0xf);
918 
919 	return 0;
920 }
921 
922 #ifdef CONFIG_PPC32
923 
924 static void pmac_cpu_die(void)
925 {
926 	int cpu = smp_processor_id();
927 
928 	local_irq_disable();
929 	idle_task_exit();
930 	pr_debug("CPU%d offline\n", cpu);
931 	generic_set_cpu_dead(cpu);
932 	smp_wmb();
933 	mb();
934 	low_cpu_die();
935 }
936 
937 #else /* CONFIG_PPC32 */
938 
939 static void pmac_cpu_die(void)
940 {
941 	int cpu = smp_processor_id();
942 
943 	local_irq_disable();
944 	idle_task_exit();
945 
946 	/*
947 	 * turn off as much as possible, we'll be
948 	 * kicked out as this will only be invoked
949 	 * on core99 platforms for now ...
950 	 */
951 
952 	printk(KERN_INFO "CPU#%d offline\n", cpu);
953 	generic_set_cpu_dead(cpu);
954 	smp_wmb();
955 
956 	/*
957 	 * Re-enable interrupts. The NAP code needs to enable them
958 	 * anyways, do it now so we deal with the case where one already
959 	 * happened while soft-disabled.
960 	 * We shouldn't get any external interrupts, only decrementer, and the
961 	 * decrementer handler is safe for use on offline CPUs
962 	 */
963 	local_irq_enable();
964 
965 	while (1) {
966 		/* let's not take timer interrupts too often ... */
967 		set_dec(0x7fffffff);
968 
969 		/* Enter NAP mode */
970 		power4_idle();
971 	}
972 }
973 
974 #endif /* else CONFIG_PPC32 */
975 #endif /* CONFIG_HOTPLUG_CPU */
976 
977 /* Core99 Macs (dual G4s and G5s) */
978 static struct smp_ops_t core99_smp_ops = {
979 	.message_pass	= smp_mpic_message_pass,
980 	.probe		= smp_core99_probe,
981 #ifdef CONFIG_PPC64
982 	.bringup_done	= smp_core99_bringup_done,
983 #endif
984 	.kick_cpu	= smp_core99_kick_cpu,
985 	.setup_cpu	= smp_core99_setup_cpu,
986 	.give_timebase	= smp_core99_give_timebase,
987 	.take_timebase	= smp_core99_take_timebase,
988 #if defined(CONFIG_HOTPLUG_CPU)
989 	.cpu_disable	= smp_core99_cpu_disable,
990 	.cpu_die	= generic_cpu_die,
991 #endif
992 };
993 
994 void __init pmac_setup_smp(void)
995 {
996 	struct device_node *np;
997 
998 	/* Check for Core99 */
999 	np = of_find_node_by_name(NULL, "uni-n");
1000 	if (!np)
1001 		np = of_find_node_by_name(NULL, "u3");
1002 	if (!np)
1003 		np = of_find_node_by_name(NULL, "u4");
1004 	if (np) {
1005 		of_node_put(np);
1006 		smp_ops = &core99_smp_ops;
1007 	}
1008 #ifdef CONFIG_PPC_PMAC32_PSURGE
1009 	else {
1010 		/* We have to set bits in cpu_possible_mask here since the
1011 		 * secondary CPU(s) aren't in the device tree. Various
1012 		 * things won't be initialized for CPUs not in the possible
1013 		 * map, so we really need to fix it up here.
1014 		 */
1015 		int cpu;
1016 
1017 		for (cpu = 1; cpu < 4 && cpu < NR_CPUS; ++cpu)
1018 			set_cpu_possible(cpu, true);
1019 		smp_ops = &psurge_smp_ops;
1020 	}
1021 #endif /* CONFIG_PPC_PMAC32_PSURGE */
1022 
1023 #ifdef CONFIG_HOTPLUG_CPU
1024 	ppc_md.cpu_die = pmac_cpu_die;
1025 #endif
1026 }
1027 
1028 
1029