xref: /openbmc/linux/arch/powerpc/kernel/setup_64.c (revision 37be287c)
1 /*
2  *
3  * Common boot and setup code.
4  *
5  * Copyright (C) 2001 PPC64 Team, IBM Corp
6  *
7  *      This program is free software; you can redistribute it and/or
8  *      modify it under the terms of the GNU General Public License
9  *      as published by the Free Software Foundation; either version
10  *      2 of the License, or (at your option) any later version.
11  */
12 
13 #define DEBUG
14 
15 #include <linux/export.h>
16 #include <linux/string.h>
17 #include <linux/sched.h>
18 #include <linux/init.h>
19 #include <linux/kernel.h>
20 #include <linux/reboot.h>
21 #include <linux/delay.h>
22 #include <linux/initrd.h>
23 #include <linux/seq_file.h>
24 #include <linux/ioport.h>
25 #include <linux/console.h>
26 #include <linux/utsname.h>
27 #include <linux/tty.h>
28 #include <linux/root_dev.h>
29 #include <linux/notifier.h>
30 #include <linux/cpu.h>
31 #include <linux/unistd.h>
32 #include <linux/serial.h>
33 #include <linux/serial_8250.h>
34 #include <linux/bootmem.h>
35 #include <linux/pci.h>
36 #include <linux/lockdep.h>
37 #include <linux/memblock.h>
38 #include <linux/hugetlb.h>
39 
40 #include <asm/io.h>
41 #include <asm/kdump.h>
42 #include <asm/prom.h>
43 #include <asm/processor.h>
44 #include <asm/pgtable.h>
45 #include <asm/smp.h>
46 #include <asm/elf.h>
47 #include <asm/machdep.h>
48 #include <asm/paca.h>
49 #include <asm/time.h>
50 #include <asm/cputable.h>
51 #include <asm/sections.h>
52 #include <asm/btext.h>
53 #include <asm/nvram.h>
54 #include <asm/setup.h>
55 #include <asm/rtas.h>
56 #include <asm/iommu.h>
57 #include <asm/serial.h>
58 #include <asm/cache.h>
59 #include <asm/page.h>
60 #include <asm/mmu.h>
61 #include <asm/firmware.h>
62 #include <asm/xmon.h>
63 #include <asm/udbg.h>
64 #include <asm/kexec.h>
65 #include <asm/mmu_context.h>
66 #include <asm/code-patching.h>
67 #include <asm/kvm_ppc.h>
68 #include <asm/hugetlb.h>
69 #include <asm/epapr_hcalls.h>
70 
71 #ifdef DEBUG
72 #define DBG(fmt...) udbg_printf(fmt)
73 #else
74 #define DBG(fmt...)
75 #endif
76 
77 int boot_cpuid = 0;
78 int spinning_secondaries;
79 u64 ppc64_pft_size;
80 
81 /* Pick defaults since we might want to patch instructions
82  * before we've read this from the device tree.
83  */
84 struct ppc64_caches ppc64_caches = {
85 	.dline_size = 0x40,
86 	.log_dline_size = 6,
87 	.iline_size = 0x40,
88 	.log_iline_size = 6
89 };
90 EXPORT_SYMBOL_GPL(ppc64_caches);
91 
92 /*
93  * These are used in binfmt_elf.c to put aux entries on the stack
94  * for each elf executable being started.
95  */
96 int dcache_bsize;
97 int icache_bsize;
98 int ucache_bsize;
99 
100 #if defined(CONFIG_PPC_BOOK3E) && defined(CONFIG_SMP)
101 static void setup_tlb_core_data(void)
102 {
103 	int cpu;
104 
105 	for_each_possible_cpu(cpu) {
106 		int first = cpu_first_thread_sibling(cpu);
107 
108 		paca[cpu].tcd_ptr = &paca[first].tcd;
109 
110 		/*
111 		 * If we have threads, we need either tlbsrx.
112 		 * or e6500 tablewalk mode, or else TLB handlers
113 		 * will be racy and could produce duplicate entries.
114 		 */
115 		if (smt_enabled_at_boot >= 2 &&
116 		    !mmu_has_feature(MMU_FTR_USE_TLBRSRV) &&
117 		    book3e_htw_mode != PPC_HTW_E6500) {
118 			/* Should we panic instead? */
119 			WARN_ONCE("%s: unsupported MMU configuration -- expect problems\n",
120 				  __func__);
121 		}
122 	}
123 }
124 #else
125 static void setup_tlb_core_data(void)
126 {
127 }
128 #endif
129 
130 #ifdef CONFIG_SMP
131 
132 static char *smt_enabled_cmdline;
133 
134 /* Look for ibm,smt-enabled OF option */
135 static void check_smt_enabled(void)
136 {
137 	struct device_node *dn;
138 	const char *smt_option;
139 
140 	/* Default to enabling all threads */
141 	smt_enabled_at_boot = threads_per_core;
142 
143 	/* Allow the command line to overrule the OF option */
144 	if (smt_enabled_cmdline) {
145 		if (!strcmp(smt_enabled_cmdline, "on"))
146 			smt_enabled_at_boot = threads_per_core;
147 		else if (!strcmp(smt_enabled_cmdline, "off"))
148 			smt_enabled_at_boot = 0;
149 		else {
150 			long smt;
151 			int rc;
152 
153 			rc = strict_strtol(smt_enabled_cmdline, 10, &smt);
154 			if (!rc)
155 				smt_enabled_at_boot =
156 					min(threads_per_core, (int)smt);
157 		}
158 	} else {
159 		dn = of_find_node_by_path("/options");
160 		if (dn) {
161 			smt_option = of_get_property(dn, "ibm,smt-enabled",
162 						     NULL);
163 
164 			if (smt_option) {
165 				if (!strcmp(smt_option, "on"))
166 					smt_enabled_at_boot = threads_per_core;
167 				else if (!strcmp(smt_option, "off"))
168 					smt_enabled_at_boot = 0;
169 			}
170 
171 			of_node_put(dn);
172 		}
173 	}
174 }
175 
176 /* Look for smt-enabled= cmdline option */
177 static int __init early_smt_enabled(char *p)
178 {
179 	smt_enabled_cmdline = p;
180 	return 0;
181 }
182 early_param("smt-enabled", early_smt_enabled);
183 
184 #else
185 #define check_smt_enabled()
186 #endif /* CONFIG_SMP */
187 
188 /** Fix up paca fields required for the boot cpu */
189 static void fixup_boot_paca(void)
190 {
191 	/* The boot cpu is started */
192 	get_paca()->cpu_start = 1;
193 	/* Allow percpu accesses to work until we setup percpu data */
194 	get_paca()->data_offset = 0;
195 }
196 
197 /*
198  * Early initialization entry point. This is called by head.S
199  * with MMU translation disabled. We rely on the "feature" of
200  * the CPU that ignores the top 2 bits of the address in real
201  * mode so we can access kernel globals normally provided we
202  * only toy with things in the RMO region. From here, we do
203  * some early parsing of the device-tree to setup out MEMBLOCK
204  * data structures, and allocate & initialize the hash table
205  * and segment tables so we can start running with translation
206  * enabled.
207  *
208  * It is this function which will call the probe() callback of
209  * the various platform types and copy the matching one to the
210  * global ppc_md structure. Your platform can eventually do
211  * some very early initializations from the probe() routine, but
212  * this is not recommended, be very careful as, for example, the
213  * device-tree is not accessible via normal means at this point.
214  */
215 
216 void __init early_setup(unsigned long dt_ptr)
217 {
218 	static __initdata struct paca_struct boot_paca;
219 
220 	/* -------- printk is _NOT_ safe to use here ! ------- */
221 
222 	/* Identify CPU type */
223 	identify_cpu(0, mfspr(SPRN_PVR));
224 
225 	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
226 	initialise_paca(&boot_paca, 0);
227 	setup_paca(&boot_paca);
228 	fixup_boot_paca();
229 
230 	/* Initialize lockdep early or else spinlocks will blow */
231 	lockdep_init();
232 
233 	/* -------- printk is now safe to use ------- */
234 
235 	/* Enable early debugging if any specified (see udbg.h) */
236 	udbg_early_init();
237 
238  	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
239 
240 	/*
241 	 * Do early initialization using the flattened device
242 	 * tree, such as retrieving the physical memory map or
243 	 * calculating/retrieving the hash table size.
244 	 */
245 	early_init_devtree(__va(dt_ptr));
246 
247 	epapr_paravirt_early_init();
248 
249 	/* Now we know the logical id of our boot cpu, setup the paca. */
250 	setup_paca(&paca[boot_cpuid]);
251 	fixup_boot_paca();
252 
253 	/* Probe the machine type */
254 	probe_machine();
255 
256 	setup_kdump_trampoline();
257 
258 	DBG("Found, Initializing memory management...\n");
259 
260 	/* Initialize the hash table or TLB handling */
261 	early_init_mmu();
262 
263 	kvm_cma_reserve();
264 
265 	/*
266 	 * Reserve any gigantic pages requested on the command line.
267 	 * memblock needs to have been initialized by the time this is
268 	 * called since this will reserve memory.
269 	 */
270 	reserve_hugetlb_gpages();
271 
272 	DBG(" <- early_setup()\n");
273 
274 #ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
275 	/*
276 	 * This needs to be done *last* (after the above DBG() even)
277 	 *
278 	 * Right after we return from this function, we turn on the MMU
279 	 * which means the real-mode access trick that btext does will
280 	 * no longer work, it needs to switch to using a real MMU
281 	 * mapping. This call will ensure that it does
282 	 */
283 	btext_map();
284 #endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
285 }
286 
287 #ifdef CONFIG_SMP
288 void early_setup_secondary(void)
289 {
290 	/* Mark interrupts enabled in PACA */
291 	get_paca()->soft_enabled = 0;
292 
293 	/* Initialize the hash table or TLB handling */
294 	early_init_mmu_secondary();
295 }
296 
297 #endif /* CONFIG_SMP */
298 
299 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
300 void smp_release_cpus(void)
301 {
302 	unsigned long *ptr;
303 	int i;
304 
305 	DBG(" -> smp_release_cpus()\n");
306 
307 	/* All secondary cpus are spinning on a common spinloop, release them
308 	 * all now so they can start to spin on their individual paca
309 	 * spinloops. For non SMP kernels, the secondary cpus never get out
310 	 * of the common spinloop.
311 	 */
312 
313 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
314 			- PHYSICAL_START);
315 	*ptr = __pa(generic_secondary_smp_init);
316 
317 	/* And wait a bit for them to catch up */
318 	for (i = 0; i < 100000; i++) {
319 		mb();
320 		HMT_low();
321 		if (spinning_secondaries == 0)
322 			break;
323 		udelay(1);
324 	}
325 	DBG("spinning_secondaries = %d\n", spinning_secondaries);
326 
327 	DBG(" <- smp_release_cpus()\n");
328 }
329 #endif /* CONFIG_SMP || CONFIG_KEXEC */
330 
331 /*
332  * Initialize some remaining members of the ppc64_caches and systemcfg
333  * structures
334  * (at least until we get rid of them completely). This is mostly some
335  * cache informations about the CPU that will be used by cache flush
336  * routines and/or provided to userland
337  */
338 static void __init initialize_cache_info(void)
339 {
340 	struct device_node *np;
341 	unsigned long num_cpus = 0;
342 
343 	DBG(" -> initialize_cache_info()\n");
344 
345 	for_each_node_by_type(np, "cpu") {
346 		num_cpus += 1;
347 
348 		/*
349 		 * We're assuming *all* of the CPUs have the same
350 		 * d-cache and i-cache sizes... -Peter
351 		 */
352 		if (num_cpus == 1) {
353 			const __be32 *sizep, *lsizep;
354 			u32 size, lsize;
355 
356 			size = 0;
357 			lsize = cur_cpu_spec->dcache_bsize;
358 			sizep = of_get_property(np, "d-cache-size", NULL);
359 			if (sizep != NULL)
360 				size = be32_to_cpu(*sizep);
361 			lsizep = of_get_property(np, "d-cache-block-size",
362 						 NULL);
363 			/* fallback if block size missing */
364 			if (lsizep == NULL)
365 				lsizep = of_get_property(np,
366 							 "d-cache-line-size",
367 							 NULL);
368 			if (lsizep != NULL)
369 				lsize = be32_to_cpu(*lsizep);
370 			if (sizep == NULL || lsizep == NULL)
371 				DBG("Argh, can't find dcache properties ! "
372 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
373 
374 			ppc64_caches.dsize = size;
375 			ppc64_caches.dline_size = lsize;
376 			ppc64_caches.log_dline_size = __ilog2(lsize);
377 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
378 
379 			size = 0;
380 			lsize = cur_cpu_spec->icache_bsize;
381 			sizep = of_get_property(np, "i-cache-size", NULL);
382 			if (sizep != NULL)
383 				size = be32_to_cpu(*sizep);
384 			lsizep = of_get_property(np, "i-cache-block-size",
385 						 NULL);
386 			if (lsizep == NULL)
387 				lsizep = of_get_property(np,
388 							 "i-cache-line-size",
389 							 NULL);
390 			if (lsizep != NULL)
391 				lsize = be32_to_cpu(*lsizep);
392 			if (sizep == NULL || lsizep == NULL)
393 				DBG("Argh, can't find icache properties ! "
394 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
395 
396 			ppc64_caches.isize = size;
397 			ppc64_caches.iline_size = lsize;
398 			ppc64_caches.log_iline_size = __ilog2(lsize);
399 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
400 		}
401 	}
402 
403 	DBG(" <- initialize_cache_info()\n");
404 }
405 
406 
407 /*
408  * Do some initial setup of the system.  The parameters are those which
409  * were passed in from the bootloader.
410  */
411 void __init setup_system(void)
412 {
413 	DBG(" -> setup_system()\n");
414 
415 	/* Apply the CPUs-specific and firmware specific fixups to kernel
416 	 * text (nop out sections not relevant to this CPU or this firmware)
417 	 */
418 	do_feature_fixups(cur_cpu_spec->cpu_features,
419 			  &__start___ftr_fixup, &__stop___ftr_fixup);
420 	do_feature_fixups(cur_cpu_spec->mmu_features,
421 			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
422 	do_feature_fixups(powerpc_firmware_features,
423 			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
424 	do_lwsync_fixups(cur_cpu_spec->cpu_features,
425 			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
426 	do_final_fixups();
427 
428 	/*
429 	 * Unflatten the device-tree passed by prom_init or kexec
430 	 */
431 	unflatten_device_tree();
432 
433 	/*
434 	 * Fill the ppc64_caches & systemcfg structures with informations
435  	 * retrieved from the device-tree.
436 	 */
437 	initialize_cache_info();
438 
439 #ifdef CONFIG_PPC_RTAS
440 	/*
441 	 * Initialize RTAS if available
442 	 */
443 	rtas_initialize();
444 #endif /* CONFIG_PPC_RTAS */
445 
446 	/*
447 	 * Check if we have an initrd provided via the device-tree
448 	 */
449 	check_for_initrd();
450 
451 	/*
452 	 * Do some platform specific early initializations, that includes
453 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
454 	 * related options that will be used by finish_device_tree()
455 	 */
456 	if (ppc_md.init_early)
457 		ppc_md.init_early();
458 
459  	/*
460 	 * We can discover serial ports now since the above did setup the
461 	 * hash table management for us, thus ioremap works. We do that early
462 	 * so that further code can be debugged
463 	 */
464 	find_legacy_serial_ports();
465 
466 	/*
467 	 * Register early console
468 	 */
469 	register_early_udbg_console();
470 
471 	/*
472 	 * Initialize xmon
473 	 */
474 	xmon_setup();
475 
476 	smp_setup_cpu_maps();
477 	check_smt_enabled();
478 	setup_tlb_core_data();
479 
480 #ifdef CONFIG_SMP
481 	/* Release secondary cpus out of their spinloops at 0x60 now that
482 	 * we can map physical -> logical CPU ids
483 	 */
484 	smp_release_cpus();
485 #endif
486 
487 	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
488 
489 	printk("-----------------------------------------------------\n");
490 	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
491 	printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
492 	if (ppc64_caches.dline_size != 0x80)
493 		printk("ppc64_caches.dcache_line_size = 0x%x\n",
494 		       ppc64_caches.dline_size);
495 	if (ppc64_caches.iline_size != 0x80)
496 		printk("ppc64_caches.icache_line_size = 0x%x\n",
497 		       ppc64_caches.iline_size);
498 #ifdef CONFIG_PPC_STD_MMU_64
499 	if (htab_address)
500 		printk("htab_address                  = 0x%p\n", htab_address);
501 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
502 #endif /* CONFIG_PPC_STD_MMU_64 */
503 	if (PHYSICAL_START > 0)
504 		printk("physical_start                = 0x%llx\n",
505 		       (unsigned long long)PHYSICAL_START);
506 	printk("-----------------------------------------------------\n");
507 
508 	DBG(" <- setup_system()\n");
509 }
510 
511 /* This returns the limit below which memory accesses to the linear
512  * mapping are guarnateed not to cause a TLB or SLB miss. This is
513  * used to allocate interrupt or emergency stacks for which our
514  * exception entry path doesn't deal with being interrupted.
515  */
516 static u64 safe_stack_limit(void)
517 {
518 #ifdef CONFIG_PPC_BOOK3E
519 	/* Freescale BookE bolts the entire linear mapping */
520 	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
521 		return linear_map_top;
522 	/* Other BookE, we assume the first GB is bolted */
523 	return 1ul << 30;
524 #else
525 	/* BookS, the first segment is bolted */
526 	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
527 		return 1UL << SID_SHIFT_1T;
528 	return 1UL << SID_SHIFT;
529 #endif
530 }
531 
532 static void __init irqstack_early_init(void)
533 {
534 	u64 limit = safe_stack_limit();
535 	unsigned int i;
536 
537 	/*
538 	 * Interrupt stacks must be in the first segment since we
539 	 * cannot afford to take SLB misses on them.
540 	 */
541 	for_each_possible_cpu(i) {
542 		softirq_ctx[i] = (struct thread_info *)
543 			__va(memblock_alloc_base(THREAD_SIZE,
544 					    THREAD_SIZE, limit));
545 		hardirq_ctx[i] = (struct thread_info *)
546 			__va(memblock_alloc_base(THREAD_SIZE,
547 					    THREAD_SIZE, limit));
548 	}
549 }
550 
551 #ifdef CONFIG_PPC_BOOK3E
552 static void __init exc_lvl_early_init(void)
553 {
554 	unsigned int i;
555 
556 	for_each_possible_cpu(i) {
557 		critirq_ctx[i] = (struct thread_info *)
558 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
559 		dbgirq_ctx[i] = (struct thread_info *)
560 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
561 		mcheckirq_ctx[i] = (struct thread_info *)
562 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
563 	}
564 
565 	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
566 		patch_exception(0x040, exc_debug_debug_book3e);
567 }
568 #else
569 #define exc_lvl_early_init()
570 #endif
571 
572 /*
573  * Stack space used when we detect a bad kernel stack pointer, and
574  * early in SMP boots before relocation is enabled. Exclusive emergency
575  * stack for machine checks.
576  */
577 static void __init emergency_stack_init(void)
578 {
579 	u64 limit;
580 	unsigned int i;
581 
582 	/*
583 	 * Emergency stacks must be under 256MB, we cannot afford to take
584 	 * SLB misses on them. The ABI also requires them to be 128-byte
585 	 * aligned.
586 	 *
587 	 * Since we use these as temporary stacks during secondary CPU
588 	 * bringup, we need to get at them in real mode. This means they
589 	 * must also be within the RMO region.
590 	 */
591 	limit = min(safe_stack_limit(), ppc64_rma_size);
592 
593 	for_each_possible_cpu(i) {
594 		unsigned long sp;
595 		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
596 		sp += THREAD_SIZE;
597 		paca[i].emergency_sp = __va(sp);
598 
599 #ifdef CONFIG_PPC_BOOK3S_64
600 		/* emergency stack for machine check exception handling. */
601 		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
602 		sp += THREAD_SIZE;
603 		paca[i].mc_emergency_sp = __va(sp);
604 #endif
605 	}
606 }
607 
608 /*
609  * Called into from start_kernel this initializes bootmem, which is used
610  * to manage page allocation until mem_init is called.
611  */
612 void __init setup_arch(char **cmdline_p)
613 {
614 	ppc64_boot_msg(0x12, "Setup Arch");
615 
616 	*cmdline_p = cmd_line;
617 
618 	/*
619 	 * Set cache line size based on type of cpu as a default.
620 	 * Systems with OF can look in the properties on the cpu node(s)
621 	 * for a possibly more accurate value.
622 	 */
623 	dcache_bsize = ppc64_caches.dline_size;
624 	icache_bsize = ppc64_caches.iline_size;
625 
626 	if (ppc_md.panic)
627 		setup_panic();
628 
629 	init_mm.start_code = (unsigned long)_stext;
630 	init_mm.end_code = (unsigned long) _etext;
631 	init_mm.end_data = (unsigned long) _edata;
632 	init_mm.brk = klimit;
633 #ifdef CONFIG_PPC_64K_PAGES
634 	init_mm.context.pte_frag = NULL;
635 #endif
636 	irqstack_early_init();
637 	exc_lvl_early_init();
638 	emergency_stack_init();
639 
640 #ifdef CONFIG_PPC_STD_MMU_64
641 	stabs_alloc();
642 #endif
643 	/* set up the bootmem stuff with available memory */
644 	do_init_bootmem();
645 	sparse_init();
646 
647 #ifdef CONFIG_DUMMY_CONSOLE
648 	conswitchp = &dummy_con;
649 #endif
650 
651 	if (ppc_md.setup_arch)
652 		ppc_md.setup_arch();
653 
654 	paging_init();
655 
656 	/* Initialize the MMU context management stuff */
657 	mmu_context_init();
658 
659 	/* Interrupt code needs to be 64K-aligned */
660 	if ((unsigned long)_stext & 0xffff)
661 		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
662 		      (unsigned long)_stext);
663 
664 	ppc64_boot_msg(0x15, "Setup Done");
665 }
666 
667 
668 /* ToDo: do something useful if ppc_md is not yet setup. */
669 #define PPC64_LINUX_FUNCTION 0x0f000000
670 #define PPC64_IPL_MESSAGE 0xc0000000
671 #define PPC64_TERM_MESSAGE 0xb0000000
672 
673 static void ppc64_do_msg(unsigned int src, const char *msg)
674 {
675 	if (ppc_md.progress) {
676 		char buf[128];
677 
678 		sprintf(buf, "%08X\n", src);
679 		ppc_md.progress(buf, 0);
680 		snprintf(buf, 128, "%s", msg);
681 		ppc_md.progress(buf, 0);
682 	}
683 }
684 
685 /* Print a boot progress message. */
686 void ppc64_boot_msg(unsigned int src, const char *msg)
687 {
688 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
689 	printk("[boot]%04x %s\n", src, msg);
690 }
691 
692 #ifdef CONFIG_SMP
693 #define PCPU_DYN_SIZE		()
694 
695 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
696 {
697 	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
698 				    __pa(MAX_DMA_ADDRESS));
699 }
700 
701 static void __init pcpu_fc_free(void *ptr, size_t size)
702 {
703 	free_bootmem(__pa(ptr), size);
704 }
705 
706 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
707 {
708 	if (cpu_to_node(from) == cpu_to_node(to))
709 		return LOCAL_DISTANCE;
710 	else
711 		return REMOTE_DISTANCE;
712 }
713 
714 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
715 EXPORT_SYMBOL(__per_cpu_offset);
716 
717 void __init setup_per_cpu_areas(void)
718 {
719 	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
720 	size_t atom_size;
721 	unsigned long delta;
722 	unsigned int cpu;
723 	int rc;
724 
725 	/*
726 	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
727 	 * to group units.  For larger mappings, use 1M atom which
728 	 * should be large enough to contain a number of units.
729 	 */
730 	if (mmu_linear_psize == MMU_PAGE_4K)
731 		atom_size = PAGE_SIZE;
732 	else
733 		atom_size = 1 << 20;
734 
735 	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
736 				    pcpu_fc_alloc, pcpu_fc_free);
737 	if (rc < 0)
738 		panic("cannot initialize percpu area (err=%d)", rc);
739 
740 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
741 	for_each_possible_cpu(cpu) {
742                 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
743 		paca[cpu].data_offset = __per_cpu_offset[cpu];
744 	}
745 }
746 #endif
747 
748 
749 #if defined(CONFIG_PPC_INDIRECT_PIO) || defined(CONFIG_PPC_INDIRECT_MMIO)
750 struct ppc_pci_io ppc_pci_io;
751 EXPORT_SYMBOL(ppc_pci_io);
752 #endif
753