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/sched/hotplug.h>
27 #include <linux/smp.h>
28 #include <linux/interrupt.h>
29 #include <linux/kernel_stat.h>
30 #include <linux/delay.h>
31 #include <linux/init.h>
32 #include <linux/spinlock.h>
33 #include <linux/errno.h>
34 #include <linux/hardirq.h>
35 #include <linux/cpu.h>
36 #include <linux/compiler.h>
37 
38 #include <asm/ptrace.h>
39 #include <linux/atomic.h>
40 #include <asm/code-patching.h>
41 #include <asm/irq.h>
42 #include <asm/page.h>
43 #include <asm/pgtable.h>
44 #include <asm/sections.h>
45 #include <asm/io.h>
46 #include <asm/prom.h>
47 #include <asm/smp.h>
48 #include <asm/machdep.h>
49 #include <asm/pmac_feature.h>
50 #include <asm/time.h>
51 #include <asm/mpic.h>
52 #include <asm/cacheflush.h>
53 #include <asm/keylargo.h>
54 #include <asm/pmac_low_i2c.h>
55 #include <asm/pmac_pfunc.h>
56 
57 #include "pmac.h"
58 
59 #undef DEBUG
60 
61 #ifdef DEBUG
62 #define DBG(fmt...) udbg_printf(fmt)
63 #else
64 #define DBG(fmt...)
65 #endif
66 
67 extern void __secondary_start_pmac_0(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_domain *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)
175 {
176 	psurge_set_ipi(cpu);
177 }
178 
179 static int psurge_host_map(struct irq_domain *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 static const struct irq_domain_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_domain_add_nomap(NULL, ~0, &psurge_host_ops, NULL);
196 
197 	if (psurge_host)
198 		psurge_secondary_virq = irq_create_direct_mapping(psurge_host);
199 
200 	if (psurge_secondary_virq)
201 		rc = request_irq(psurge_secondary_virq, psurge_ipi_intr,
202 			IRQF_PERCPU | IRQF_NO_THREAD, "IPI", NULL);
203 
204 	if (rc)
205 		pr_err("Failed to setup secondary cpu IPI\n");
206 
207 	return rc;
208 }
209 
210 /*
211  * Determine a quad card presence. We read the board ID register, we
212  * force the data bus to change to something else, and we read it again.
213  * It it's stable, then the register probably exist (ugh !)
214  */
215 static int __init psurge_quad_probe(void)
216 {
217 	int type;
218 	unsigned int i;
219 
220 	type = PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID);
221 	if (type < PSURGE_QUAD_OKEE || type > PSURGE_QUAD_ICEGRASS
222 	    || type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
223 		return PSURGE_DUAL;
224 
225 	/* looks OK, try a slightly more rigorous test */
226 	/* bogus is not necessarily cacheline-aligned,
227 	   though I don't suppose that really matters.  -- paulus */
228 	for (i = 0; i < 100; i++) {
229 		volatile u32 bogus[8];
230 		bogus[(0+i)%8] = 0x00000000;
231 		bogus[(1+i)%8] = 0x55555555;
232 		bogus[(2+i)%8] = 0xFFFFFFFF;
233 		bogus[(3+i)%8] = 0xAAAAAAAA;
234 		bogus[(4+i)%8] = 0x33333333;
235 		bogus[(5+i)%8] = 0xCCCCCCCC;
236 		bogus[(6+i)%8] = 0xCCCCCCCC;
237 		bogus[(7+i)%8] = 0x33333333;
238 		wmb();
239 		asm volatile("dcbf 0,%0" : : "r" (bogus) : "memory");
240 		mb();
241 		if (type != PSURGE_QUAD_IN(PSURGE_QUAD_BOARD_ID))
242 			return PSURGE_DUAL;
243 	}
244 	return type;
245 }
246 
247 static void __init psurge_quad_init(void)
248 {
249 	int procbits;
250 
251 	if (ppc_md.progress) ppc_md.progress("psurge_quad_init", 0x351);
252 	procbits = ~PSURGE_QUAD_IN(PSURGE_QUAD_WHICH_CPU);
253 	if (psurge_type == PSURGE_QUAD_ICEGRASS)
254 		PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
255 	else
256 		PSURGE_QUAD_BIC(PSURGE_QUAD_CKSTOP_CTL, procbits);
257 	mdelay(33);
258 	out_8(psurge_sec_intr, ~0);
259 	PSURGE_QUAD_OUT(PSURGE_QUAD_IRQ_CLR, procbits);
260 	PSURGE_QUAD_BIS(PSURGE_QUAD_RESET_CTL, procbits);
261 	if (psurge_type != PSURGE_QUAD_ICEGRASS)
262 		PSURGE_QUAD_BIS(PSURGE_QUAD_CKSTOP_CTL, procbits);
263 	PSURGE_QUAD_BIC(PSURGE_QUAD_PRIMARY_ARB, procbits);
264 	mdelay(33);
265 	PSURGE_QUAD_BIC(PSURGE_QUAD_RESET_CTL, procbits);
266 	mdelay(33);
267 	PSURGE_QUAD_BIS(PSURGE_QUAD_PRIMARY_ARB, procbits);
268 	mdelay(33);
269 }
270 
271 static void __init smp_psurge_probe(void)
272 {
273 	int i, ncpus;
274 	struct device_node *dn;
275 
276 	/* We don't do SMP on the PPC601 -- paulus */
277 	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
278 		return;
279 
280 	/*
281 	 * The powersurge cpu board can be used in the generation
282 	 * of powermacs that have a socket for an upgradeable cpu card,
283 	 * including the 7500, 8500, 9500, 9600.
284 	 * The device tree doesn't tell you if you have 2 cpus because
285 	 * OF doesn't know anything about the 2nd processor.
286 	 * Instead we look for magic bits in magic registers,
287 	 * in the hammerhead memory controller in the case of the
288 	 * dual-cpu powersurge board.  -- paulus.
289 	 */
290 	dn = of_find_node_by_name(NULL, "hammerhead");
291 	if (dn == NULL)
292 		return;
293 	of_node_put(dn);
294 
295 	hhead_base = ioremap(HAMMERHEAD_BASE, 0x800);
296 	quad_base = ioremap(PSURGE_QUAD_REG_ADDR, 1024);
297 	psurge_sec_intr = hhead_base + HHEAD_SEC_INTR;
298 
299 	psurge_type = psurge_quad_probe();
300 	if (psurge_type != PSURGE_DUAL) {
301 		psurge_quad_init();
302 		/* All released cards using this HW design have 4 CPUs */
303 		ncpus = 4;
304 		/* No sure how timebase sync works on those, let's use SW */
305 		smp_ops->give_timebase = smp_generic_give_timebase;
306 		smp_ops->take_timebase = smp_generic_take_timebase;
307 	} else {
308 		iounmap(quad_base);
309 		if ((in_8(hhead_base + HHEAD_CONFIG) & 0x02) == 0) {
310 			/* not a dual-cpu card */
311 			iounmap(hhead_base);
312 			psurge_type = PSURGE_NONE;
313 			return;
314 		}
315 		ncpus = 2;
316 	}
317 
318 	if (psurge_secondary_ipi_init())
319 		return;
320 
321 	psurge_start = ioremap(PSURGE_START, 4);
322 	psurge_pri_intr = ioremap(PSURGE_PRI_INTR, 4);
323 
324 	/* This is necessary because OF doesn't know about the
325 	 * secondary cpu(s), and thus there aren't nodes in the
326 	 * device tree for them, and smp_setup_cpu_maps hasn't
327 	 * set their bits in cpu_present_mask.
328 	 */
329 	if (ncpus > NR_CPUS)
330 		ncpus = NR_CPUS;
331 	for (i = 1; i < ncpus ; ++i)
332 		set_cpu_present(i, true);
333 
334 	if (ppc_md.progress) ppc_md.progress("smp_psurge_probe - done", 0x352);
335 }
336 
337 static int __init smp_psurge_kick_cpu(int nr)
338 {
339 	unsigned long start = __pa(__secondary_start_pmac_0) + nr * 8;
340 	unsigned long a, flags;
341 	int i, j;
342 
343 	/* Defining this here is evil ... but I prefer hiding that
344 	 * crap to avoid giving people ideas that they can do the
345 	 * same.
346 	 */
347 	extern volatile unsigned int cpu_callin_map[NR_CPUS];
348 
349 	/* may need to flush here if secondary bats aren't setup */
350 	for (a = KERNELBASE; a < KERNELBASE + 0x800000; a += 32)
351 		asm volatile("dcbf 0,%0" : : "r" (a) : "memory");
352 	asm volatile("sync");
353 
354 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu", 0x353);
355 
356 	/* This is going to freeze the timeebase, we disable interrupts */
357 	local_irq_save(flags);
358 
359 	out_be32(psurge_start, start);
360 	mb();
361 
362 	psurge_set_ipi(nr);
363 
364 	/*
365 	 * We can't use udelay here because the timebase is now frozen.
366 	 */
367 	for (i = 0; i < 2000; ++i)
368 		asm volatile("nop" : : : "memory");
369 	psurge_clr_ipi(nr);
370 
371 	/*
372 	 * Also, because the timebase is frozen, we must not return to the
373 	 * caller which will try to do udelay's etc... Instead, we wait -here-
374 	 * for the CPU to callin.
375 	 */
376 	for (i = 0; i < 100000 && !cpu_callin_map[nr]; ++i) {
377 		for (j = 1; j < 10000; j++)
378 			asm volatile("nop" : : : "memory");
379 		asm volatile("sync" : : : "memory");
380 	}
381 	if (!cpu_callin_map[nr])
382 		goto stuck;
383 
384 	/* And we do the TB sync here too for standard dual CPU cards */
385 	if (psurge_type == PSURGE_DUAL) {
386 		while(!tb_req)
387 			barrier();
388 		tb_req = 0;
389 		mb();
390 		timebase = get_tb();
391 		mb();
392 		while (timebase)
393 			barrier();
394 		mb();
395 	}
396  stuck:
397 	/* now interrupt the secondary, restarting both TBs */
398 	if (psurge_type == PSURGE_DUAL)
399 		psurge_set_ipi(1);
400 
401 	if (ppc_md.progress) ppc_md.progress("smp_psurge_kick_cpu - done", 0x354);
402 
403 	return 0;
404 }
405 
406 static struct irqaction psurge_irqaction = {
407 	.handler = psurge_ipi_intr,
408 	.flags = IRQF_PERCPU | IRQF_NO_THREAD,
409 	.name = "primary IPI",
410 };
411 
412 static void __init smp_psurge_setup_cpu(int cpu_nr)
413 {
414 	if (cpu_nr != 0 || !psurge_start)
415 		return;
416 
417 	/* reset the entry point so if we get another intr we won't
418 	 * try to startup again */
419 	out_be32(psurge_start, 0x100);
420 	if (setup_irq(irq_create_mapping(NULL, 30), &psurge_irqaction))
421 		printk(KERN_ERR "Couldn't get primary IPI interrupt");
422 }
423 
424 void __init smp_psurge_take_timebase(void)
425 {
426 	if (psurge_type != PSURGE_DUAL)
427 		return;
428 
429 	tb_req = 1;
430 	mb();
431 	while (!timebase)
432 		barrier();
433 	mb();
434 	set_tb(timebase >> 32, timebase & 0xffffffff);
435 	timebase = 0;
436 	mb();
437 	set_dec(tb_ticks_per_jiffy/2);
438 }
439 
440 void __init smp_psurge_give_timebase(void)
441 {
442 	/* Nothing to do here */
443 }
444 
445 /* PowerSurge-style Macs */
446 struct smp_ops_t psurge_smp_ops = {
447 	.message_pass	= NULL,	/* Use smp_muxed_ipi_message_pass */
448 	.cause_ipi	= smp_psurge_cause_ipi,
449 	.cause_nmi_ipi	= NULL,
450 	.probe		= smp_psurge_probe,
451 	.kick_cpu	= smp_psurge_kick_cpu,
452 	.setup_cpu	= smp_psurge_setup_cpu,
453 	.give_timebase	= smp_psurge_give_timebase,
454 	.take_timebase	= smp_psurge_take_timebase,
455 };
456 #endif /* CONFIG_PPC_PMAC32_PSURGE */
457 
458 /*
459  * Core 99 and later support
460  */
461 
462 
463 static void smp_core99_give_timebase(void)
464 {
465 	unsigned long flags;
466 
467 	local_irq_save(flags);
468 
469 	while(!tb_req)
470 		barrier();
471 	tb_req = 0;
472 	(*pmac_tb_freeze)(1);
473 	mb();
474 	timebase = get_tb();
475 	mb();
476 	while (timebase)
477 		barrier();
478 	mb();
479 	(*pmac_tb_freeze)(0);
480 	mb();
481 
482 	local_irq_restore(flags);
483 }
484 
485 
486 static void smp_core99_take_timebase(void)
487 {
488 	unsigned long flags;
489 
490 	local_irq_save(flags);
491 
492 	tb_req = 1;
493 	mb();
494 	while (!timebase)
495 		barrier();
496 	mb();
497 	set_tb(timebase >> 32, timebase & 0xffffffff);
498 	timebase = 0;
499 	mb();
500 
501 	local_irq_restore(flags);
502 }
503 
504 #ifdef CONFIG_PPC64
505 /*
506  * G5s enable/disable the timebase via an i2c-connected clock chip.
507  */
508 static struct pmac_i2c_bus *pmac_tb_clock_chip_host;
509 static u8 pmac_tb_pulsar_addr;
510 
511 static void smp_core99_cypress_tb_freeze(int freeze)
512 {
513 	u8 data;
514 	int rc;
515 
516 	/* Strangely, the device-tree says address is 0xd2, but darwin
517 	 * accesses 0xd0 ...
518 	 */
519 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
520 			 pmac_i2c_mode_combined);
521 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
522 			   0xd0 | pmac_i2c_read,
523 			   1, 0x81, &data, 1);
524 	if (rc != 0)
525 		goto bail;
526 
527 	data = (data & 0xf3) | (freeze ? 0x00 : 0x0c);
528 
529        	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
530 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
531 			   0xd0 | pmac_i2c_write,
532 			   1, 0x81, &data, 1);
533 
534  bail:
535 	if (rc != 0) {
536 		printk("Cypress Timebase %s rc: %d\n",
537 		       freeze ? "freeze" : "unfreeze", rc);
538 		panic("Timebase freeze failed !\n");
539 	}
540 }
541 
542 
543 static void smp_core99_pulsar_tb_freeze(int freeze)
544 {
545 	u8 data;
546 	int rc;
547 
548 	pmac_i2c_setmode(pmac_tb_clock_chip_host,
549 			 pmac_i2c_mode_combined);
550 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
551 			   pmac_tb_pulsar_addr | pmac_i2c_read,
552 			   1, 0x2e, &data, 1);
553 	if (rc != 0)
554 		goto bail;
555 
556 	data = (data & 0x88) | (freeze ? 0x11 : 0x22);
557 
558 	pmac_i2c_setmode(pmac_tb_clock_chip_host, pmac_i2c_mode_stdsub);
559 	rc = pmac_i2c_xfer(pmac_tb_clock_chip_host,
560 			   pmac_tb_pulsar_addr | pmac_i2c_write,
561 			   1, 0x2e, &data, 1);
562  bail:
563 	if (rc != 0) {
564 		printk(KERN_ERR "Pulsar Timebase %s rc: %d\n",
565 		       freeze ? "freeze" : "unfreeze", rc);
566 		panic("Timebase freeze failed !\n");
567 	}
568 }
569 
570 static void __init smp_core99_setup_i2c_hwsync(int ncpus)
571 {
572 	struct device_node *cc = NULL;
573 	struct device_node *p;
574 	const char *name = NULL;
575 	const u32 *reg;
576 	int ok;
577 
578 	/* Look for the clock chip */
579 	for_each_node_by_name(cc, "i2c-hwclock") {
580 		p = of_get_parent(cc);
581 		ok = p && of_device_is_compatible(p, "uni-n-i2c");
582 		of_node_put(p);
583 		if (!ok)
584 			continue;
585 
586 		pmac_tb_clock_chip_host = pmac_i2c_find_bus(cc);
587 		if (pmac_tb_clock_chip_host == NULL)
588 			continue;
589 		reg = of_get_property(cc, "reg", NULL);
590 		if (reg == NULL)
591 			continue;
592 		switch (*reg) {
593 		case 0xd2:
594 			if (of_device_is_compatible(cc,"pulsar-legacy-slewing")) {
595 				pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
596 				pmac_tb_pulsar_addr = 0xd2;
597 				name = "Pulsar";
598 			} else if (of_device_is_compatible(cc, "cy28508")) {
599 				pmac_tb_freeze = smp_core99_cypress_tb_freeze;
600 				name = "Cypress";
601 			}
602 			break;
603 		case 0xd4:
604 			pmac_tb_freeze = smp_core99_pulsar_tb_freeze;
605 			pmac_tb_pulsar_addr = 0xd4;
606 			name = "Pulsar";
607 			break;
608 		}
609 		if (pmac_tb_freeze != NULL)
610 			break;
611 	}
612 	if (pmac_tb_freeze != NULL) {
613 		/* Open i2c bus for synchronous access */
614 		if (pmac_i2c_open(pmac_tb_clock_chip_host, 1)) {
615 			printk(KERN_ERR "Failed top open i2c bus for clock"
616 			       " sync, fallback to software sync !\n");
617 			goto no_i2c_sync;
618 		}
619 		printk(KERN_INFO "Processor timebase sync using %s i2c clock\n",
620 		       name);
621 		return;
622 	}
623  no_i2c_sync:
624 	pmac_tb_freeze = NULL;
625 	pmac_tb_clock_chip_host = NULL;
626 }
627 
628 
629 
630 /*
631  * Newer G5s uses a platform function
632  */
633 
634 static void smp_core99_pfunc_tb_freeze(int freeze)
635 {
636 	struct device_node *cpus;
637 	struct pmf_args args;
638 
639 	cpus = of_find_node_by_path("/cpus");
640 	BUG_ON(cpus == NULL);
641 	args.count = 1;
642 	args.u[0].v = !freeze;
643 	pmf_call_function(cpus, "cpu-timebase", &args);
644 	of_node_put(cpus);
645 }
646 
647 #else /* CONFIG_PPC64 */
648 
649 /*
650  * SMP G4 use a GPIO to enable/disable the timebase.
651  */
652 
653 static unsigned int core99_tb_gpio;	/* Timebase freeze GPIO */
654 
655 static void smp_core99_gpio_tb_freeze(int freeze)
656 {
657 	if (freeze)
658 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 4);
659 	else
660 		pmac_call_feature(PMAC_FTR_WRITE_GPIO, NULL, core99_tb_gpio, 0);
661 	pmac_call_feature(PMAC_FTR_READ_GPIO, NULL, core99_tb_gpio, 0);
662 }
663 
664 
665 #endif /* !CONFIG_PPC64 */
666 
667 /* L2 and L3 cache settings to pass from CPU0 to CPU1 on G4 cpus */
668 volatile static long int core99_l2_cache;
669 volatile static long int core99_l3_cache;
670 
671 static void core99_init_caches(int cpu)
672 {
673 #ifndef CONFIG_PPC64
674 	if (!cpu_has_feature(CPU_FTR_L2CR))
675 		return;
676 
677 	if (cpu == 0) {
678 		core99_l2_cache = _get_L2CR();
679 		printk("CPU0: L2CR is %lx\n", core99_l2_cache);
680 	} else {
681 		printk("CPU%d: L2CR was %lx\n", cpu, _get_L2CR());
682 		_set_L2CR(0);
683 		_set_L2CR(core99_l2_cache);
684 		printk("CPU%d: L2CR set to %lx\n", cpu, core99_l2_cache);
685 	}
686 
687 	if (!cpu_has_feature(CPU_FTR_L3CR))
688 		return;
689 
690 	if (cpu == 0){
691 		core99_l3_cache = _get_L3CR();
692 		printk("CPU0: L3CR is %lx\n", core99_l3_cache);
693 	} else {
694 		printk("CPU%d: L3CR was %lx\n", cpu, _get_L3CR());
695 		_set_L3CR(0);
696 		_set_L3CR(core99_l3_cache);
697 		printk("CPU%d: L3CR set to %lx\n", cpu, core99_l3_cache);
698 	}
699 #endif /* !CONFIG_PPC64 */
700 }
701 
702 static void __init smp_core99_setup(int ncpus)
703 {
704 #ifdef CONFIG_PPC64
705 
706 	/* i2c based HW sync on some G5s */
707 	if (of_machine_is_compatible("PowerMac7,2") ||
708 	    of_machine_is_compatible("PowerMac7,3") ||
709 	    of_machine_is_compatible("RackMac3,1"))
710 		smp_core99_setup_i2c_hwsync(ncpus);
711 
712 	/* pfunc based HW sync on recent G5s */
713 	if (pmac_tb_freeze == NULL) {
714 		struct device_node *cpus =
715 			of_find_node_by_path("/cpus");
716 		if (cpus &&
717 		    of_get_property(cpus, "platform-cpu-timebase", NULL)) {
718 			pmac_tb_freeze = smp_core99_pfunc_tb_freeze;
719 			printk(KERN_INFO "Processor timebase sync using"
720 			       " platform function\n");
721 		}
722 	}
723 
724 #else /* CONFIG_PPC64 */
725 
726 	/* GPIO based HW sync on ppc32 Core99 */
727 	if (pmac_tb_freeze == NULL && !of_machine_is_compatible("MacRISC4")) {
728 		struct device_node *cpu;
729 		const u32 *tbprop = NULL;
730 
731 		core99_tb_gpio = KL_GPIO_TB_ENABLE;	/* default value */
732 		cpu = of_find_node_by_type(NULL, "cpu");
733 		if (cpu != NULL) {
734 			tbprop = of_get_property(cpu, "timebase-enable", NULL);
735 			if (tbprop)
736 				core99_tb_gpio = *tbprop;
737 			of_node_put(cpu);
738 		}
739 		pmac_tb_freeze = smp_core99_gpio_tb_freeze;
740 		printk(KERN_INFO "Processor timebase sync using"
741 		       " GPIO 0x%02x\n", core99_tb_gpio);
742 	}
743 
744 #endif /* CONFIG_PPC64 */
745 
746 	/* No timebase sync, fallback to software */
747 	if (pmac_tb_freeze == NULL) {
748 		smp_ops->give_timebase = smp_generic_give_timebase;
749 		smp_ops->take_timebase = smp_generic_take_timebase;
750 		printk(KERN_INFO "Processor timebase sync using software\n");
751 	}
752 
753 #ifndef CONFIG_PPC64
754 	{
755 		int i;
756 
757 		/* XXX should get this from reg properties */
758 		for (i = 1; i < ncpus; ++i)
759 			set_hard_smp_processor_id(i, i);
760 	}
761 #endif
762 
763 	/* 32 bits SMP can't NAP */
764 	if (!of_machine_is_compatible("MacRISC4"))
765 		powersave_nap = 0;
766 }
767 
768 static void __init smp_core99_probe(void)
769 {
770 	struct device_node *cpus;
771 	int ncpus = 0;
772 
773 	if (ppc_md.progress) ppc_md.progress("smp_core99_probe", 0x345);
774 
775 	/* Count CPUs in the device-tree */
776 	for_each_node_by_type(cpus, "cpu")
777 		++ncpus;
778 
779 	printk(KERN_INFO "PowerMac SMP probe found %d cpus\n", ncpus);
780 
781 	/* Nothing more to do if less than 2 of them */
782 	if (ncpus <= 1)
783 		return;
784 
785 	/* We need to perform some early initialisations before we can start
786 	 * setting up SMP as we are running before initcalls
787 	 */
788 	pmac_pfunc_base_install();
789 	pmac_i2c_init();
790 
791 	/* Setup various bits like timebase sync method, ability to nap, ... */
792 	smp_core99_setup(ncpus);
793 
794 	/* Install IPIs */
795 	mpic_request_ipis();
796 
797 	/* Collect l2cr and l3cr values from CPU 0 */
798 	core99_init_caches(0);
799 }
800 
801 static int smp_core99_kick_cpu(int nr)
802 {
803 	unsigned int save_vector;
804 	unsigned long target, flags;
805 	unsigned int *vector = (unsigned int *)(PAGE_OFFSET+0x100);
806 
807 	if (nr < 0 || nr > 3)
808 		return -ENOENT;
809 
810 	if (ppc_md.progress)
811 		ppc_md.progress("smp_core99_kick_cpu", 0x346);
812 
813 	local_irq_save(flags);
814 
815 	/* Save reset vector */
816 	save_vector = *vector;
817 
818 	/* Setup fake reset vector that does
819 	 *   b __secondary_start_pmac_0 + nr*8
820 	 */
821 	target = (unsigned long) __secondary_start_pmac_0 + nr * 8;
822 	patch_branch(vector, target, BRANCH_SET_LINK);
823 
824 	/* Put some life in our friend */
825 	pmac_call_feature(PMAC_FTR_RESET_CPU, NULL, nr, 0);
826 
827 	/* FIXME: We wait a bit for the CPU to take the exception, I should
828 	 * instead wait for the entry code to set something for me. Well,
829 	 * ideally, all that crap will be done in prom.c and the CPU left
830 	 * in a RAM-based wait loop like CHRP.
831 	 */
832 	mdelay(1);
833 
834 	/* Restore our exception vector */
835 	patch_instruction(vector, save_vector);
836 
837 	local_irq_restore(flags);
838 	if (ppc_md.progress) ppc_md.progress("smp_core99_kick_cpu done", 0x347);
839 
840 	return 0;
841 }
842 
843 static void smp_core99_setup_cpu(int cpu_nr)
844 {
845 	/* Setup L2/L3 */
846 	if (cpu_nr != 0)
847 		core99_init_caches(cpu_nr);
848 
849 	/* Setup openpic */
850 	mpic_setup_this_cpu();
851 }
852 
853 #ifdef CONFIG_PPC64
854 #ifdef CONFIG_HOTPLUG_CPU
855 static unsigned int smp_core99_host_open;
856 
857 static int smp_core99_cpu_prepare(unsigned int cpu)
858 {
859 	int rc;
860 
861 	/* Open i2c bus if it was used for tb sync */
862 	if (pmac_tb_clock_chip_host && !smp_core99_host_open) {
863 		rc = pmac_i2c_open(pmac_tb_clock_chip_host, 1);
864 		if (rc) {
865 			pr_err("Failed to open i2c bus for time sync\n");
866 			return notifier_from_errno(rc);
867 		}
868 		smp_core99_host_open = 1;
869 	}
870 	return 0;
871 }
872 
873 static int smp_core99_cpu_online(unsigned int cpu)
874 {
875 	/* Close i2c bus if it was used for tb sync */
876 	if (pmac_tb_clock_chip_host && smp_core99_host_open) {
877 		pmac_i2c_close(pmac_tb_clock_chip_host);
878 		smp_core99_host_open = 0;
879 	}
880 	return 0;
881 }
882 #endif /* CONFIG_HOTPLUG_CPU */
883 
884 static void __init smp_core99_bringup_done(void)
885 {
886 	extern void g5_phy_disable_cpu1(void);
887 
888 	/* Close i2c bus if it was used for tb sync */
889 	if (pmac_tb_clock_chip_host)
890 		pmac_i2c_close(pmac_tb_clock_chip_host);
891 
892 	/* If we didn't start the second CPU, we must take
893 	 * it off the bus.
894 	 */
895 	if (of_machine_is_compatible("MacRISC4") &&
896 	    num_online_cpus() < 2) {
897 		set_cpu_present(1, false);
898 		g5_phy_disable_cpu1();
899 	}
900 #ifdef CONFIG_HOTPLUG_CPU
901 	cpuhp_setup_state_nocalls(CPUHP_POWERPC_PMAC_PREPARE,
902 				  "powerpc/pmac:prepare", smp_core99_cpu_prepare,
903 				  NULL);
904 	cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "powerpc/pmac:online",
905 				  smp_core99_cpu_online, NULL);
906 #endif
907 
908 	if (ppc_md.progress)
909 		ppc_md.progress("smp_core99_bringup_done", 0x349);
910 }
911 #endif /* CONFIG_PPC64 */
912 
913 #ifdef CONFIG_HOTPLUG_CPU
914 
915 static int smp_core99_cpu_disable(void)
916 {
917 	int rc = generic_cpu_disable();
918 	if (rc)
919 		return rc;
920 
921 	mpic_cpu_set_priority(0xf);
922 
923 	return 0;
924 }
925 
926 #ifdef CONFIG_PPC32
927 
928 static void pmac_cpu_die(void)
929 {
930 	int cpu = smp_processor_id();
931 
932 	local_irq_disable();
933 	idle_task_exit();
934 	pr_debug("CPU%d offline\n", cpu);
935 	generic_set_cpu_dead(cpu);
936 	smp_wmb();
937 	mb();
938 	low_cpu_die();
939 }
940 
941 #else /* CONFIG_PPC32 */
942 
943 static void pmac_cpu_die(void)
944 {
945 	int cpu = smp_processor_id();
946 
947 	local_irq_disable();
948 	idle_task_exit();
949 
950 	/*
951 	 * turn off as much as possible, we'll be
952 	 * kicked out as this will only be invoked
953 	 * on core99 platforms for now ...
954 	 */
955 
956 	printk(KERN_INFO "CPU#%d offline\n", cpu);
957 	generic_set_cpu_dead(cpu);
958 	smp_wmb();
959 
960 	/*
961 	 * Re-enable interrupts. The NAP code needs to enable them
962 	 * anyways, do it now so we deal with the case where one already
963 	 * happened while soft-disabled.
964 	 * We shouldn't get any external interrupts, only decrementer, and the
965 	 * decrementer handler is safe for use on offline CPUs
966 	 */
967 	local_irq_enable();
968 
969 	while (1) {
970 		/* let's not take timer interrupts too often ... */
971 		set_dec(0x7fffffff);
972 
973 		/* Enter NAP mode */
974 		power4_idle();
975 	}
976 }
977 
978 #endif /* else CONFIG_PPC32 */
979 #endif /* CONFIG_HOTPLUG_CPU */
980 
981 /* Core99 Macs (dual G4s and G5s) */
982 static struct smp_ops_t core99_smp_ops = {
983 	.message_pass	= smp_mpic_message_pass,
984 	.probe		= smp_core99_probe,
985 #ifdef CONFIG_PPC64
986 	.bringup_done	= smp_core99_bringup_done,
987 #endif
988 	.kick_cpu	= smp_core99_kick_cpu,
989 	.setup_cpu	= smp_core99_setup_cpu,
990 	.give_timebase	= smp_core99_give_timebase,
991 	.take_timebase	= smp_core99_take_timebase,
992 #if defined(CONFIG_HOTPLUG_CPU)
993 	.cpu_disable	= smp_core99_cpu_disable,
994 	.cpu_die	= generic_cpu_die,
995 #endif
996 };
997 
998 void __init pmac_setup_smp(void)
999 {
1000 	struct device_node *np;
1001 
1002 	/* Check for Core99 */
1003 	np = of_find_node_by_name(NULL, "uni-n");
1004 	if (!np)
1005 		np = of_find_node_by_name(NULL, "u3");
1006 	if (!np)
1007 		np = of_find_node_by_name(NULL, "u4");
1008 	if (np) {
1009 		of_node_put(np);
1010 		smp_ops = &core99_smp_ops;
1011 	}
1012 #ifdef CONFIG_PPC_PMAC32_PSURGE
1013 	else {
1014 		/* We have to set bits in cpu_possible_mask here since the
1015 		 * secondary CPU(s) aren't in the device tree. Various
1016 		 * things won't be initialized for CPUs not in the possible
1017 		 * map, so we really need to fix it up here.
1018 		 */
1019 		int cpu;
1020 
1021 		for (cpu = 1; cpu < 4 && cpu < NR_CPUS; ++cpu)
1022 			set_cpu_possible(cpu, true);
1023 		smp_ops = &psurge_smp_ops;
1024 	}
1025 #endif /* CONFIG_PPC_PMAC32_PSURGE */
1026 
1027 #ifdef CONFIG_HOTPLUG_CPU
1028 	ppc_md.cpu_die = pmac_cpu_die;
1029 #endif
1030 }
1031 
1032 
1033