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#include <linux/memory.h>
40#include <linux/nmi.h>
41
42#include <asm/io.h>
43#include <asm/kdump.h>
44#include <asm/prom.h>
45#include <asm/processor.h>
46#include <asm/pgtable.h>
47#include <asm/smp.h>
48#include <asm/elf.h>
49#include <asm/machdep.h>
50#include <asm/paca.h>
51#include <asm/time.h>
52#include <asm/cputable.h>
53#include <asm/sections.h>
54#include <asm/btext.h>
55#include <asm/nvram.h>
56#include <asm/setup.h>
57#include <asm/rtas.h>
58#include <asm/iommu.h>
59#include <asm/serial.h>
60#include <asm/cache.h>
61#include <asm/page.h>
62#include <asm/mmu.h>
63#include <asm/firmware.h>
64#include <asm/xmon.h>
65#include <asm/udbg.h>
66#include <asm/kexec.h>
67#include <asm/mmu_context.h>
68#include <asm/code-patching.h>
69#include <asm/kvm_ppc.h>
70#include <asm/hugetlb.h>
71#include <asm/epapr_hcalls.h>
72
73#ifdef DEBUG
74#define DBG(fmt...) udbg_printf(fmt)
75#else
76#define DBG(fmt...)
77#endif
78
79int spinning_secondaries;
80u64 ppc64_pft_size;
81
82/* Pick defaults since we might want to patch instructions
83 * before we've read this from the device tree.
84 */
85struct ppc64_caches ppc64_caches = {
86	.dline_size = 0x40,
87	.log_dline_size = 6,
88	.iline_size = 0x40,
89	.log_iline_size = 6
90};
91EXPORT_SYMBOL_GPL(ppc64_caches);
92
93/*
94 * These are used in binfmt_elf.c to put aux entries on the stack
95 * for each elf executable being started.
96 */
97int dcache_bsize;
98int icache_bsize;
99int ucache_bsize;
100
101#if defined(CONFIG_PPC_BOOK3E) && defined(CONFIG_SMP)
102static void setup_tlb_core_data(void)
103{
104	int cpu;
105
106	BUILD_BUG_ON(offsetof(struct tlb_core_data, lock) != 0);
107
108	for_each_possible_cpu(cpu) {
109		int first = cpu_first_thread_sibling(cpu);
110
111		paca[cpu].tcd_ptr = &paca[first].tcd;
112
113		/*
114		 * If we have threads, we need either tlbsrx.
115		 * or e6500 tablewalk mode, or else TLB handlers
116		 * will be racy and could produce duplicate entries.
117		 */
118		if (smt_enabled_at_boot >= 2 &&
119		    !mmu_has_feature(MMU_FTR_USE_TLBRSRV) &&
120		    book3e_htw_mode != PPC_HTW_E6500) {
121			/* Should we panic instead? */
122			WARN_ONCE("%s: unsupported MMU configuration -- expect problems\n",
123				  __func__);
124		}
125	}
126}
127#else
128static void setup_tlb_core_data(void)
129{
130}
131#endif
132
133#ifdef CONFIG_SMP
134
135static char *smt_enabled_cmdline;
136
137/* Look for ibm,smt-enabled OF option */
138static void check_smt_enabled(void)
139{
140	struct device_node *dn;
141	const char *smt_option;
142
143	/* Default to enabling all threads */
144	smt_enabled_at_boot = threads_per_core;
145
146	/* Allow the command line to overrule the OF option */
147	if (smt_enabled_cmdline) {
148		if (!strcmp(smt_enabled_cmdline, "on"))
149			smt_enabled_at_boot = threads_per_core;
150		else if (!strcmp(smt_enabled_cmdline, "off"))
151			smt_enabled_at_boot = 0;
152		else {
153			int smt;
154			int rc;
155
156			rc = kstrtoint(smt_enabled_cmdline, 10, &smt);
157			if (!rc)
158				smt_enabled_at_boot =
159					min(threads_per_core, smt);
160		}
161	} else {
162		dn = of_find_node_by_path("/options");
163		if (dn) {
164			smt_option = of_get_property(dn, "ibm,smt-enabled",
165						     NULL);
166
167			if (smt_option) {
168				if (!strcmp(smt_option, "on"))
169					smt_enabled_at_boot = threads_per_core;
170				else if (!strcmp(smt_option, "off"))
171					smt_enabled_at_boot = 0;
172			}
173
174			of_node_put(dn);
175		}
176	}
177}
178
179/* Look for smt-enabled= cmdline option */
180static int __init early_smt_enabled(char *p)
181{
182	smt_enabled_cmdline = p;
183	return 0;
184}
185early_param("smt-enabled", early_smt_enabled);
186
187#else
188#define check_smt_enabled()
189#endif /* CONFIG_SMP */
190
191/** Fix up paca fields required for the boot cpu */
192static void fixup_boot_paca(void)
193{
194	/* The boot cpu is started */
195	get_paca()->cpu_start = 1;
196	/* Allow percpu accesses to work until we setup percpu data */
197	get_paca()->data_offset = 0;
198}
199
200static void cpu_ready_for_interrupts(void)
201{
202	/* Set IR and DR in PACA MSR */
203	get_paca()->kernel_msr = MSR_KERNEL;
204
205	/*
206	 * Enable AIL if supported, and we are in hypervisor mode. If we are
207	 * not in hypervisor mode, we enable relocation-on interrupts later
208	 * in pSeries_setup_arch() using the H_SET_MODE hcall.
209	 */
210	if (cpu_has_feature(CPU_FTR_HVMODE) &&
211	    cpu_has_feature(CPU_FTR_ARCH_207S)) {
212		unsigned long lpcr = mfspr(SPRN_LPCR);
213		mtspr(SPRN_LPCR, lpcr | LPCR_AIL_3);
214	}
215}
216
217/*
218 * Early initialization entry point. This is called by head.S
219 * with MMU translation disabled. We rely on the "feature" of
220 * the CPU that ignores the top 2 bits of the address in real
221 * mode so we can access kernel globals normally provided we
222 * only toy with things in the RMO region. From here, we do
223 * some early parsing of the device-tree to setup out MEMBLOCK
224 * data structures, and allocate & initialize the hash table
225 * and segment tables so we can start running with translation
226 * enabled.
227 *
228 * It is this function which will call the probe() callback of
229 * the various platform types and copy the matching one to the
230 * global ppc_md structure. Your platform can eventually do
231 * some very early initializations from the probe() routine, but
232 * this is not recommended, be very careful as, for example, the
233 * device-tree is not accessible via normal means at this point.
234 */
235
236void __init early_setup(unsigned long dt_ptr)
237{
238	static __initdata struct paca_struct boot_paca;
239
240	/* -------- printk is _NOT_ safe to use here ! ------- */
241
242	/* Identify CPU type */
243	identify_cpu(0, mfspr(SPRN_PVR));
244
245	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
246	initialise_paca(&boot_paca, 0);
247	setup_paca(&boot_paca);
248	fixup_boot_paca();
249
250	/* Initialize lockdep early or else spinlocks will blow */
251	lockdep_init();
252
253	/* -------- printk is now safe to use ------- */
254
255	/* Enable early debugging if any specified (see udbg.h) */
256	udbg_early_init();
257
258 	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
259
260	/*
261	 * Do early initialization using the flattened device
262	 * tree, such as retrieving the physical memory map or
263	 * calculating/retrieving the hash table size.
264	 */
265	early_init_devtree(__va(dt_ptr));
266
267	epapr_paravirt_early_init();
268
269	/* Now we know the logical id of our boot cpu, setup the paca. */
270	setup_paca(&paca[boot_cpuid]);
271	fixup_boot_paca();
272
273	/* Probe the machine type */
274	probe_machine();
275
276	setup_kdump_trampoline();
277
278	DBG("Found, Initializing memory management...\n");
279
280	/* Initialize the hash table or TLB handling */
281	early_init_mmu();
282
283	/*
284	 * At this point, we can let interrupts switch to virtual mode
285	 * (the MMU has been setup), so adjust the MSR in the PACA to
286	 * have IR and DR set and enable AIL if it exists
287	 */
288	cpu_ready_for_interrupts();
289
290	/* Reserve large chunks of memory for use by CMA for KVM */
291	kvm_cma_reserve();
292
293	/*
294	 * Reserve any gigantic pages requested on the command line.
295	 * memblock needs to have been initialized by the time this is
296	 * called since this will reserve memory.
297	 */
298	reserve_hugetlb_gpages();
299
300	DBG(" <- early_setup()\n");
301
302#ifdef CONFIG_PPC_EARLY_DEBUG_BOOTX
303	/*
304	 * This needs to be done *last* (after the above DBG() even)
305	 *
306	 * Right after we return from this function, we turn on the MMU
307	 * which means the real-mode access trick that btext does will
308	 * no longer work, it needs to switch to using a real MMU
309	 * mapping. This call will ensure that it does
310	 */
311	btext_map();
312#endif /* CONFIG_PPC_EARLY_DEBUG_BOOTX */
313}
314
315#ifdef CONFIG_SMP
316void early_setup_secondary(void)
317{
318	/* Mark interrupts enabled in PACA */
319	get_paca()->soft_enabled = 0;
320
321	/* Initialize the hash table or TLB handling */
322	early_init_mmu_secondary();
323
324	/*
325	 * At this point, we can let interrupts switch to virtual mode
326	 * (the MMU has been setup), so adjust the MSR in the PACA to
327	 * have IR and DR set.
328	 */
329	cpu_ready_for_interrupts();
330}
331
332#endif /* CONFIG_SMP */
333
334#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
335void smp_release_cpus(void)
336{
337	unsigned long *ptr;
338	int i;
339
340	DBG(" -> smp_release_cpus()\n");
341
342	/* All secondary cpus are spinning on a common spinloop, release them
343	 * all now so they can start to spin on their individual paca
344	 * spinloops. For non SMP kernels, the secondary cpus never get out
345	 * of the common spinloop.
346	 */
347
348	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
349			- PHYSICAL_START);
350	*ptr = ppc_function_entry(generic_secondary_smp_init);
351
352	/* And wait a bit for them to catch up */
353	for (i = 0; i < 100000; i++) {
354		mb();
355		HMT_low();
356		if (spinning_secondaries == 0)
357			break;
358		udelay(1);
359	}
360	DBG("spinning_secondaries = %d\n", spinning_secondaries);
361
362	DBG(" <- smp_release_cpus()\n");
363}
364#endif /* CONFIG_SMP || CONFIG_KEXEC */
365
366/*
367 * Initialize some remaining members of the ppc64_caches and systemcfg
368 * structures
369 * (at least until we get rid of them completely). This is mostly some
370 * cache informations about the CPU that will be used by cache flush
371 * routines and/or provided to userland
372 */
373static void __init initialize_cache_info(void)
374{
375	struct device_node *np;
376	unsigned long num_cpus = 0;
377
378	DBG(" -> initialize_cache_info()\n");
379
380	for_each_node_by_type(np, "cpu") {
381		num_cpus += 1;
382
383		/*
384		 * We're assuming *all* of the CPUs have the same
385		 * d-cache and i-cache sizes... -Peter
386		 */
387		if (num_cpus == 1) {
388			const __be32 *sizep, *lsizep;
389			u32 size, lsize;
390
391			size = 0;
392			lsize = cur_cpu_spec->dcache_bsize;
393			sizep = of_get_property(np, "d-cache-size", NULL);
394			if (sizep != NULL)
395				size = be32_to_cpu(*sizep);
396			lsizep = of_get_property(np, "d-cache-block-size",
397						 NULL);
398			/* fallback if block size missing */
399			if (lsizep == NULL)
400				lsizep = of_get_property(np,
401							 "d-cache-line-size",
402							 NULL);
403			if (lsizep != NULL)
404				lsize = be32_to_cpu(*lsizep);
405			if (sizep == NULL || lsizep == NULL)
406				DBG("Argh, can't find dcache properties ! "
407				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
408
409			ppc64_caches.dsize = size;
410			ppc64_caches.dline_size = lsize;
411			ppc64_caches.log_dline_size = __ilog2(lsize);
412			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
413
414			size = 0;
415			lsize = cur_cpu_spec->icache_bsize;
416			sizep = of_get_property(np, "i-cache-size", NULL);
417			if (sizep != NULL)
418				size = be32_to_cpu(*sizep);
419			lsizep = of_get_property(np, "i-cache-block-size",
420						 NULL);
421			if (lsizep == NULL)
422				lsizep = of_get_property(np,
423							 "i-cache-line-size",
424							 NULL);
425			if (lsizep != NULL)
426				lsize = be32_to_cpu(*lsizep);
427			if (sizep == NULL || lsizep == NULL)
428				DBG("Argh, can't find icache properties ! "
429				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
430
431			ppc64_caches.isize = size;
432			ppc64_caches.iline_size = lsize;
433			ppc64_caches.log_iline_size = __ilog2(lsize);
434			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
435		}
436	}
437
438	DBG(" <- initialize_cache_info()\n");
439}
440
441
442/*
443 * Do some initial setup of the system.  The parameters are those which
444 * were passed in from the bootloader.
445 */
446void __init setup_system(void)
447{
448	DBG(" -> setup_system()\n");
449
450	/* Apply the CPUs-specific and firmware specific fixups to kernel
451	 * text (nop out sections not relevant to this CPU or this firmware)
452	 */
453	do_feature_fixups(cur_cpu_spec->cpu_features,
454			  &__start___ftr_fixup, &__stop___ftr_fixup);
455	do_feature_fixups(cur_cpu_spec->mmu_features,
456			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
457	do_feature_fixups(powerpc_firmware_features,
458			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
459	do_lwsync_fixups(cur_cpu_spec->cpu_features,
460			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
461	do_final_fixups();
462
463	/*
464	 * Unflatten the device-tree passed by prom_init or kexec
465	 */
466	unflatten_device_tree();
467
468	/*
469	 * Fill the ppc64_caches & systemcfg structures with informations
470 	 * retrieved from the device-tree.
471	 */
472	initialize_cache_info();
473
474#ifdef CONFIG_PPC_RTAS
475	/*
476	 * Initialize RTAS if available
477	 */
478	rtas_initialize();
479#endif /* CONFIG_PPC_RTAS */
480
481	/*
482	 * Check if we have an initrd provided via the device-tree
483	 */
484	check_for_initrd();
485
486	/*
487	 * Do some platform specific early initializations, that includes
488	 * setting up the hash table pointers. It also sets up some interrupt-mapping
489	 * related options that will be used by finish_device_tree()
490	 */
491	if (ppc_md.init_early)
492		ppc_md.init_early();
493
494 	/*
495	 * We can discover serial ports now since the above did setup the
496	 * hash table management for us, thus ioremap works. We do that early
497	 * so that further code can be debugged
498	 */
499	find_legacy_serial_ports();
500
501	/*
502	 * Register early console
503	 */
504	register_early_udbg_console();
505
506	/*
507	 * Initialize xmon
508	 */
509	xmon_setup();
510
511	smp_setup_cpu_maps();
512	check_smt_enabled();
513	setup_tlb_core_data();
514
515	/*
516	 * Freescale Book3e parts spin in a loop provided by firmware,
517	 * so smp_release_cpus() does nothing for them
518	 */
519#if defined(CONFIG_SMP) && !defined(CONFIG_PPC_FSL_BOOK3E)
520	/* Release secondary cpus out of their spinloops at 0x60 now that
521	 * we can map physical -> logical CPU ids
522	 */
523	smp_release_cpus();
524#endif
525
526	pr_info("Starting Linux PPC64 %s\n", init_utsname()->version);
527
528	pr_info("-----------------------------------------------------\n");
529	pr_info("ppc64_pft_size    = 0x%llx\n", ppc64_pft_size);
530	pr_info("phys_mem_size     = 0x%llx\n", memblock_phys_mem_size());
531
532	if (ppc64_caches.dline_size != 0x80)
533		pr_info("dcache_line_size  = 0x%x\n", ppc64_caches.dline_size);
534	if (ppc64_caches.iline_size != 0x80)
535		pr_info("icache_line_size  = 0x%x\n", ppc64_caches.iline_size);
536
537	pr_info("cpu_features      = 0x%016lx\n", cur_cpu_spec->cpu_features);
538	pr_info("  possible        = 0x%016lx\n", CPU_FTRS_POSSIBLE);
539	pr_info("  always          = 0x%016lx\n", CPU_FTRS_ALWAYS);
540	pr_info("cpu_user_features = 0x%08x 0x%08x\n", cur_cpu_spec->cpu_user_features,
541		cur_cpu_spec->cpu_user_features2);
542	pr_info("mmu_features      = 0x%08x\n", cur_cpu_spec->mmu_features);
543	pr_info("firmware_features = 0x%016lx\n", powerpc_firmware_features);
544
545#ifdef CONFIG_PPC_STD_MMU_64
546	if (htab_address)
547		pr_info("htab_address      = 0x%p\n", htab_address);
548
549	pr_info("htab_hash_mask    = 0x%lx\n", htab_hash_mask);
550#endif
551
552	if (PHYSICAL_START > 0)
553		pr_info("physical_start    = 0x%llx\n",
554		       (unsigned long long)PHYSICAL_START);
555	pr_info("-----------------------------------------------------\n");
556
557	DBG(" <- setup_system()\n");
558}
559
560/* This returns the limit below which memory accesses to the linear
561 * mapping are guarnateed not to cause a TLB or SLB miss. This is
562 * used to allocate interrupt or emergency stacks for which our
563 * exception entry path doesn't deal with being interrupted.
564 */
565static u64 safe_stack_limit(void)
566{
567#ifdef CONFIG_PPC_BOOK3E
568	/* Freescale BookE bolts the entire linear mapping */
569	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
570		return linear_map_top;
571	/* Other BookE, we assume the first GB is bolted */
572	return 1ul << 30;
573#else
574	/* BookS, the first segment is bolted */
575	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
576		return 1UL << SID_SHIFT_1T;
577	return 1UL << SID_SHIFT;
578#endif
579}
580
581static void __init irqstack_early_init(void)
582{
583	u64 limit = safe_stack_limit();
584	unsigned int i;
585
586	/*
587	 * Interrupt stacks must be in the first segment since we
588	 * cannot afford to take SLB misses on them.
589	 */
590	for_each_possible_cpu(i) {
591		softirq_ctx[i] = (struct thread_info *)
592			__va(memblock_alloc_base(THREAD_SIZE,
593					    THREAD_SIZE, limit));
594		hardirq_ctx[i] = (struct thread_info *)
595			__va(memblock_alloc_base(THREAD_SIZE,
596					    THREAD_SIZE, limit));
597	}
598}
599
600#ifdef CONFIG_PPC_BOOK3E
601static void __init exc_lvl_early_init(void)
602{
603	unsigned int i;
604	unsigned long sp;
605
606	for_each_possible_cpu(i) {
607		sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
608		critirq_ctx[i] = (struct thread_info *)__va(sp);
609		paca[i].crit_kstack = __va(sp + THREAD_SIZE);
610
611		sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
612		dbgirq_ctx[i] = (struct thread_info *)__va(sp);
613		paca[i].dbg_kstack = __va(sp + THREAD_SIZE);
614
615		sp = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
616		mcheckirq_ctx[i] = (struct thread_info *)__va(sp);
617		paca[i].mc_kstack = __va(sp + THREAD_SIZE);
618	}
619
620	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
621		patch_exception(0x040, exc_debug_debug_book3e);
622}
623#else
624#define exc_lvl_early_init()
625#endif
626
627/*
628 * Stack space used when we detect a bad kernel stack pointer, and
629 * early in SMP boots before relocation is enabled. Exclusive emergency
630 * stack for machine checks.
631 */
632static void __init emergency_stack_init(void)
633{
634	u64 limit;
635	unsigned int i;
636
637	/*
638	 * Emergency stacks must be under 256MB, we cannot afford to take
639	 * SLB misses on them. The ABI also requires them to be 128-byte
640	 * aligned.
641	 *
642	 * Since we use these as temporary stacks during secondary CPU
643	 * bringup, we need to get at them in real mode. This means they
644	 * must also be within the RMO region.
645	 */
646	limit = min(safe_stack_limit(), ppc64_rma_size);
647
648	for_each_possible_cpu(i) {
649		unsigned long sp;
650		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
651		sp += THREAD_SIZE;
652		paca[i].emergency_sp = __va(sp);
653
654#ifdef CONFIG_PPC_BOOK3S_64
655		/* emergency stack for machine check exception handling. */
656		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
657		sp += THREAD_SIZE;
658		paca[i].mc_emergency_sp = __va(sp);
659#endif
660	}
661}
662
663/*
664 * Called into from start_kernel this initializes memblock, which is used
665 * to manage page allocation until mem_init is called.
666 */
667void __init setup_arch(char **cmdline_p)
668{
669	*cmdline_p = boot_command_line;
670
671	/*
672	 * Set cache line size based on type of cpu as a default.
673	 * Systems with OF can look in the properties on the cpu node(s)
674	 * for a possibly more accurate value.
675	 */
676	dcache_bsize = ppc64_caches.dline_size;
677	icache_bsize = ppc64_caches.iline_size;
678
679	if (ppc_md.panic)
680		setup_panic();
681
682	init_mm.start_code = (unsigned long)_stext;
683	init_mm.end_code = (unsigned long) _etext;
684	init_mm.end_data = (unsigned long) _edata;
685	init_mm.brk = klimit;
686#ifdef CONFIG_PPC_64K_PAGES
687	init_mm.context.pte_frag = NULL;
688#endif
689	irqstack_early_init();
690	exc_lvl_early_init();
691	emergency_stack_init();
692
693	initmem_init();
694
695#ifdef CONFIG_DUMMY_CONSOLE
696	conswitchp = &dummy_con;
697#endif
698
699	if (ppc_md.setup_arch)
700		ppc_md.setup_arch();
701
702	paging_init();
703
704	/* Initialize the MMU context management stuff */
705	mmu_context_init();
706
707	/* Interrupt code needs to be 64K-aligned */
708	if ((unsigned long)_stext & 0xffff)
709		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
710		      (unsigned long)_stext);
711}
712
713#ifdef CONFIG_SMP
714#define PCPU_DYN_SIZE		()
715
716static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
717{
718	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
719				    __pa(MAX_DMA_ADDRESS));
720}
721
722static void __init pcpu_fc_free(void *ptr, size_t size)
723{
724	free_bootmem(__pa(ptr), size);
725}
726
727static int pcpu_cpu_distance(unsigned int from, unsigned int to)
728{
729	if (cpu_to_node(from) == cpu_to_node(to))
730		return LOCAL_DISTANCE;
731	else
732		return REMOTE_DISTANCE;
733}
734
735unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
736EXPORT_SYMBOL(__per_cpu_offset);
737
738void __init setup_per_cpu_areas(void)
739{
740	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
741	size_t atom_size;
742	unsigned long delta;
743	unsigned int cpu;
744	int rc;
745
746	/*
747	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
748	 * to group units.  For larger mappings, use 1M atom which
749	 * should be large enough to contain a number of units.
750	 */
751	if (mmu_linear_psize == MMU_PAGE_4K)
752		atom_size = PAGE_SIZE;
753	else
754		atom_size = 1 << 20;
755
756	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
757				    pcpu_fc_alloc, pcpu_fc_free);
758	if (rc < 0)
759		panic("cannot initialize percpu area (err=%d)", rc);
760
761	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
762	for_each_possible_cpu(cpu) {
763                __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
764		paca[cpu].data_offset = __per_cpu_offset[cpu];
765	}
766}
767#endif
768
769#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
770unsigned long memory_block_size_bytes(void)
771{
772	if (ppc_md.memory_block_size)
773		return ppc_md.memory_block_size();
774
775	return MIN_MEMORY_BLOCK_SIZE;
776}
777#endif
778
779#if defined(CONFIG_PPC_INDIRECT_PIO) || defined(CONFIG_PPC_INDIRECT_MMIO)
780struct ppc_pci_io ppc_pci_io;
781EXPORT_SYMBOL(ppc_pci_io);
782#endif
783
784#ifdef CONFIG_HARDLOCKUP_DETECTOR
785u64 hw_nmi_get_sample_period(int watchdog_thresh)
786{
787	return ppc_proc_freq * watchdog_thresh;
788}
789
790/*
791 * The hardlockup detector breaks PMU event based branches and is likely
792 * to get false positives in KVM guests, so disable it by default.
793 */
794static int __init disable_hardlockup_detector(void)
795{
796	hardlockup_detector_disable();
797
798	return 0;
799}
800early_initcall(disable_hardlockup_detector);
801#endif
802