setup_64.c revision 4e21b94c9c644c43223878f4c848e852743e789c
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#undef 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#include "setup.h"
72
73#ifdef DEBUG
74#define DBG(fmt...) udbg_printf(fmt)
75#else
76#define DBG(fmt...)
77#endif
78
79int boot_cpuid = 0;
80int spinning_secondaries;
81u64 ppc64_pft_size;
82
83/* Pick defaults since we might want to patch instructions
84 * before we've read this from the device tree.
85 */
86struct ppc64_caches ppc64_caches = {
87	.dline_size = 0x40,
88	.log_dline_size = 6,
89	.iline_size = 0x40,
90	.log_iline_size = 6
91};
92EXPORT_SYMBOL_GPL(ppc64_caches);
93
94/*
95 * These are used in binfmt_elf.c to put aux entries on the stack
96 * for each elf executable being started.
97 */
98int dcache_bsize;
99int icache_bsize;
100int ucache_bsize;
101
102#ifdef CONFIG_SMP
103
104static char *smt_enabled_cmdline;
105
106/* Look for ibm,smt-enabled OF option */
107static void check_smt_enabled(void)
108{
109	struct device_node *dn;
110	const char *smt_option;
111
112	/* Default to enabling all threads */
113	smt_enabled_at_boot = threads_per_core;
114
115	/* Allow the command line to overrule the OF option */
116	if (smt_enabled_cmdline) {
117		if (!strcmp(smt_enabled_cmdline, "on"))
118			smt_enabled_at_boot = threads_per_core;
119		else if (!strcmp(smt_enabled_cmdline, "off"))
120			smt_enabled_at_boot = 0;
121		else {
122			long smt;
123			int rc;
124
125			rc = strict_strtol(smt_enabled_cmdline, 10, &smt);
126			if (!rc)
127				smt_enabled_at_boot =
128					min(threads_per_core, (int)smt);
129		}
130	} else {
131		dn = of_find_node_by_path("/options");
132		if (dn) {
133			smt_option = of_get_property(dn, "ibm,smt-enabled",
134						     NULL);
135
136			if (smt_option) {
137				if (!strcmp(smt_option, "on"))
138					smt_enabled_at_boot = threads_per_core;
139				else if (!strcmp(smt_option, "off"))
140					smt_enabled_at_boot = 0;
141			}
142
143			of_node_put(dn);
144		}
145	}
146}
147
148/* Look for smt-enabled= cmdline option */
149static int __init early_smt_enabled(char *p)
150{
151	smt_enabled_cmdline = p;
152	return 0;
153}
154early_param("smt-enabled", early_smt_enabled);
155
156#else
157#define check_smt_enabled()
158#endif /* CONFIG_SMP */
159
160/** Fix up paca fields required for the boot cpu */
161static void fixup_boot_paca(void)
162{
163	/* The boot cpu is started */
164	get_paca()->cpu_start = 1;
165	/* Allow percpu accesses to work until we setup percpu data */
166	get_paca()->data_offset = 0;
167}
168
169/*
170 * Early initialization entry point. This is called by head.S
171 * with MMU translation disabled. We rely on the "feature" of
172 * the CPU that ignores the top 2 bits of the address in real
173 * mode so we can access kernel globals normally provided we
174 * only toy with things in the RMO region. From here, we do
175 * some early parsing of the device-tree to setup out MEMBLOCK
176 * data structures, and allocate & initialize the hash table
177 * and segment tables so we can start running with translation
178 * enabled.
179 *
180 * It is this function which will call the probe() callback of
181 * the various platform types and copy the matching one to the
182 * global ppc_md structure. Your platform can eventually do
183 * some very early initializations from the probe() routine, but
184 * this is not recommended, be very careful as, for example, the
185 * device-tree is not accessible via normal means at this point.
186 */
187
188void __init early_setup(unsigned long dt_ptr)
189{
190	static __initdata struct paca_struct boot_paca;
191
192	/* -------- printk is _NOT_ safe to use here ! ------- */
193
194	/* Identify CPU type */
195	identify_cpu(0, mfspr(SPRN_PVR));
196
197	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
198	initialise_paca(&boot_paca, 0);
199	setup_paca(&boot_paca);
200	fixup_boot_paca();
201
202	/* Initialize lockdep early or else spinlocks will blow */
203	lockdep_init();
204
205	/* -------- printk is now safe to use ------- */
206
207	/* Enable early debugging if any specified (see udbg.h) */
208	udbg_early_init();
209
210 	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
211
212	/*
213	 * Do early initialization using the flattened device
214	 * tree, such as retrieving the physical memory map or
215	 * calculating/retrieving the hash table size.
216	 */
217	early_init_devtree(__va(dt_ptr));
218
219	epapr_paravirt_early_init();
220
221	/* Now we know the logical id of our boot cpu, setup the paca. */
222	setup_paca(&paca[boot_cpuid]);
223	fixup_boot_paca();
224
225	/* Probe the machine type */
226	probe_machine();
227
228	setup_kdump_trampoline();
229
230	DBG("Found, Initializing memory management...\n");
231
232	/* Initialize the hash table or TLB handling */
233	early_init_mmu();
234
235	/*
236	 * Reserve any gigantic pages requested on the command line.
237	 * memblock needs to have been initialized by the time this is
238	 * called since this will reserve memory.
239	 */
240	reserve_hugetlb_gpages();
241
242	DBG(" <- early_setup()\n");
243}
244
245#ifdef CONFIG_SMP
246void early_setup_secondary(void)
247{
248	/* Mark interrupts enabled in PACA */
249	get_paca()->soft_enabled = 0;
250
251	/* Initialize the hash table or TLB handling */
252	early_init_mmu_secondary();
253}
254
255#endif /* CONFIG_SMP */
256
257#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
258void smp_release_cpus(void)
259{
260	unsigned long *ptr;
261	int i;
262
263	DBG(" -> smp_release_cpus()\n");
264
265	/* All secondary cpus are spinning on a common spinloop, release them
266	 * all now so they can start to spin on their individual paca
267	 * spinloops. For non SMP kernels, the secondary cpus never get out
268	 * of the common spinloop.
269	 */
270
271	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
272			- PHYSICAL_START);
273	*ptr = __pa(generic_secondary_smp_init);
274
275	/* And wait a bit for them to catch up */
276	for (i = 0; i < 100000; i++) {
277		mb();
278		HMT_low();
279		if (spinning_secondaries == 0)
280			break;
281		udelay(1);
282	}
283	DBG("spinning_secondaries = %d\n", spinning_secondaries);
284
285	DBG(" <- smp_release_cpus()\n");
286}
287#endif /* CONFIG_SMP || CONFIG_KEXEC */
288
289/*
290 * Initialize some remaining members of the ppc64_caches and systemcfg
291 * structures
292 * (at least until we get rid of them completely). This is mostly some
293 * cache informations about the CPU that will be used by cache flush
294 * routines and/or provided to userland
295 */
296static void __init initialize_cache_info(void)
297{
298	struct device_node *np;
299	unsigned long num_cpus = 0;
300
301	DBG(" -> initialize_cache_info()\n");
302
303	for_each_node_by_type(np, "cpu") {
304		num_cpus += 1;
305
306		/*
307		 * We're assuming *all* of the CPUs have the same
308		 * d-cache and i-cache sizes... -Peter
309		 */
310		if (num_cpus == 1) {
311			const u32 *sizep, *lsizep;
312			u32 size, lsize;
313
314			size = 0;
315			lsize = cur_cpu_spec->dcache_bsize;
316			sizep = of_get_property(np, "d-cache-size", NULL);
317			if (sizep != NULL)
318				size = *sizep;
319			lsizep = of_get_property(np, "d-cache-block-size",
320						 NULL);
321			/* fallback if block size missing */
322			if (lsizep == NULL)
323				lsizep = of_get_property(np,
324							 "d-cache-line-size",
325							 NULL);
326			if (lsizep != NULL)
327				lsize = *lsizep;
328			if (sizep == 0 || lsizep == 0)
329				DBG("Argh, can't find dcache properties ! "
330				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
331
332			ppc64_caches.dsize = size;
333			ppc64_caches.dline_size = lsize;
334			ppc64_caches.log_dline_size = __ilog2(lsize);
335			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
336
337			size = 0;
338			lsize = cur_cpu_spec->icache_bsize;
339			sizep = of_get_property(np, "i-cache-size", NULL);
340			if (sizep != NULL)
341				size = *sizep;
342			lsizep = of_get_property(np, "i-cache-block-size",
343						 NULL);
344			if (lsizep == NULL)
345				lsizep = of_get_property(np,
346							 "i-cache-line-size",
347							 NULL);
348			if (lsizep != NULL)
349				lsize = *lsizep;
350			if (sizep == 0 || lsizep == 0)
351				DBG("Argh, can't find icache properties ! "
352				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
353
354			ppc64_caches.isize = size;
355			ppc64_caches.iline_size = lsize;
356			ppc64_caches.log_iline_size = __ilog2(lsize);
357			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
358		}
359	}
360
361	DBG(" <- initialize_cache_info()\n");
362}
363
364
365/*
366 * Do some initial setup of the system.  The parameters are those which
367 * were passed in from the bootloader.
368 */
369void __init setup_system(void)
370{
371	DBG(" -> setup_system()\n");
372
373	/* Apply the CPUs-specific and firmware specific fixups to kernel
374	 * text (nop out sections not relevant to this CPU or this firmware)
375	 */
376	do_feature_fixups(cur_cpu_spec->cpu_features,
377			  &__start___ftr_fixup, &__stop___ftr_fixup);
378	do_feature_fixups(cur_cpu_spec->mmu_features,
379			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
380	do_feature_fixups(powerpc_firmware_features,
381			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
382	do_lwsync_fixups(cur_cpu_spec->cpu_features,
383			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
384	do_final_fixups();
385
386	/*
387	 * Unflatten the device-tree passed by prom_init or kexec
388	 */
389	unflatten_device_tree();
390
391	/*
392	 * Fill the ppc64_caches & systemcfg structures with informations
393 	 * retrieved from the device-tree.
394	 */
395	initialize_cache_info();
396
397#ifdef CONFIG_PPC_RTAS
398	/*
399	 * Initialize RTAS if available
400	 */
401	rtas_initialize();
402#endif /* CONFIG_PPC_RTAS */
403
404	/*
405	 * Check if we have an initrd provided via the device-tree
406	 */
407	check_for_initrd();
408
409	/*
410	 * Do some platform specific early initializations, that includes
411	 * setting up the hash table pointers. It also sets up some interrupt-mapping
412	 * related options that will be used by finish_device_tree()
413	 */
414	if (ppc_md.init_early)
415		ppc_md.init_early();
416
417 	/*
418	 * We can discover serial ports now since the above did setup the
419	 * hash table management for us, thus ioremap works. We do that early
420	 * so that further code can be debugged
421	 */
422	find_legacy_serial_ports();
423
424	/*
425	 * Register early console
426	 */
427	register_early_udbg_console();
428
429	/*
430	 * Initialize xmon
431	 */
432	xmon_setup();
433
434	smp_setup_cpu_maps();
435	check_smt_enabled();
436
437#ifdef CONFIG_SMP
438	/* Release secondary cpus out of their spinloops at 0x60 now that
439	 * we can map physical -> logical CPU ids
440	 */
441	smp_release_cpus();
442#endif
443
444	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
445
446	printk("-----------------------------------------------------\n");
447	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
448	printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
449	if (ppc64_caches.dline_size != 0x80)
450		printk("ppc64_caches.dcache_line_size = 0x%x\n",
451		       ppc64_caches.dline_size);
452	if (ppc64_caches.iline_size != 0x80)
453		printk("ppc64_caches.icache_line_size = 0x%x\n",
454		       ppc64_caches.iline_size);
455#ifdef CONFIG_PPC_STD_MMU_64
456	if (htab_address)
457		printk("htab_address                  = 0x%p\n", htab_address);
458	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
459#endif /* CONFIG_PPC_STD_MMU_64 */
460	if (PHYSICAL_START > 0)
461		printk("physical_start                = 0x%llx\n",
462		       (unsigned long long)PHYSICAL_START);
463	printk("-----------------------------------------------------\n");
464
465	DBG(" <- setup_system()\n");
466}
467
468/* This returns the limit below which memory accesses to the linear
469 * mapping are guarnateed not to cause a TLB or SLB miss. This is
470 * used to allocate interrupt or emergency stacks for which our
471 * exception entry path doesn't deal with being interrupted.
472 */
473static u64 safe_stack_limit(void)
474{
475#ifdef CONFIG_PPC_BOOK3E
476	/* Freescale BookE bolts the entire linear mapping */
477	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
478		return linear_map_top;
479	/* Other BookE, we assume the first GB is bolted */
480	return 1ul << 30;
481#else
482	/* BookS, the first segment is bolted */
483	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
484		return 1UL << SID_SHIFT_1T;
485	return 1UL << SID_SHIFT;
486#endif
487}
488
489static void __init irqstack_early_init(void)
490{
491	u64 limit = safe_stack_limit();
492	unsigned int i;
493
494	/*
495	 * Interrupt stacks must be in the first segment since we
496	 * cannot afford to take SLB misses on them.
497	 */
498	for_each_possible_cpu(i) {
499		softirq_ctx[i] = (struct thread_info *)
500			__va(memblock_alloc_base(THREAD_SIZE,
501					    THREAD_SIZE, limit));
502		hardirq_ctx[i] = (struct thread_info *)
503			__va(memblock_alloc_base(THREAD_SIZE,
504					    THREAD_SIZE, limit));
505	}
506}
507
508#ifdef CONFIG_PPC_BOOK3E
509static void __init exc_lvl_early_init(void)
510{
511	extern unsigned int interrupt_base_book3e;
512	extern unsigned int exc_debug_debug_book3e;
513
514	unsigned int i;
515
516	for_each_possible_cpu(i) {
517		critirq_ctx[i] = (struct thread_info *)
518			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
519		dbgirq_ctx[i] = (struct thread_info *)
520			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
521		mcheckirq_ctx[i] = (struct thread_info *)
522			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
523	}
524
525	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
526		patch_branch(&interrupt_base_book3e + (0x040 / 4) + 1,
527			     (unsigned long)&exc_debug_debug_book3e, 0);
528}
529#else
530#define exc_lvl_early_init()
531#endif
532
533/*
534 * Stack space used when we detect a bad kernel stack pointer, and
535 * early in SMP boots before relocation is enabled.
536 */
537static void __init emergency_stack_init(void)
538{
539	u64 limit;
540	unsigned int i;
541
542	/*
543	 * Emergency stacks must be under 256MB, we cannot afford to take
544	 * SLB misses on them. The ABI also requires them to be 128-byte
545	 * aligned.
546	 *
547	 * Since we use these as temporary stacks during secondary CPU
548	 * bringup, we need to get at them in real mode. This means they
549	 * must also be within the RMO region.
550	 */
551	limit = min(safe_stack_limit(), ppc64_rma_size);
552
553	for_each_possible_cpu(i) {
554		unsigned long sp;
555		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
556		sp += THREAD_SIZE;
557		paca[i].emergency_sp = __va(sp);
558	}
559}
560
561/*
562 * Called into from start_kernel this initializes bootmem, which is used
563 * to manage page allocation until mem_init is called.
564 */
565void __init setup_arch(char **cmdline_p)
566{
567	ppc64_boot_msg(0x12, "Setup Arch");
568
569	*cmdline_p = cmd_line;
570
571	/*
572	 * Set cache line size based on type of cpu as a default.
573	 * Systems with OF can look in the properties on the cpu node(s)
574	 * for a possibly more accurate value.
575	 */
576	dcache_bsize = ppc64_caches.dline_size;
577	icache_bsize = ppc64_caches.iline_size;
578
579	/* reboot on panic */
580	panic_timeout = 180;
581
582	if (ppc_md.panic)
583		setup_panic();
584
585	init_mm.start_code = (unsigned long)_stext;
586	init_mm.end_code = (unsigned long) _etext;
587	init_mm.end_data = (unsigned long) _edata;
588	init_mm.brk = klimit;
589#ifdef CONFIG_PPC_64K_PAGES
590	init_mm.context.pte_frag = NULL;
591#endif
592	irqstack_early_init();
593	exc_lvl_early_init();
594	emergency_stack_init();
595
596#ifdef CONFIG_PPC_STD_MMU_64
597	stabs_alloc();
598#endif
599	/* set up the bootmem stuff with available memory */
600	do_init_bootmem();
601	sparse_init();
602
603#ifdef CONFIG_DUMMY_CONSOLE
604	conswitchp = &dummy_con;
605#endif
606
607	if (ppc_md.setup_arch)
608		ppc_md.setup_arch();
609
610	paging_init();
611
612	/* Initialize the MMU context management stuff */
613	mmu_context_init();
614
615	kvm_linear_init();
616
617	/* Interrupt code needs to be 64K-aligned */
618	if ((unsigned long)_stext & 0xffff)
619		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
620		      (unsigned long)_stext);
621
622	ppc64_boot_msg(0x15, "Setup Done");
623}
624
625
626/* ToDo: do something useful if ppc_md is not yet setup. */
627#define PPC64_LINUX_FUNCTION 0x0f000000
628#define PPC64_IPL_MESSAGE 0xc0000000
629#define PPC64_TERM_MESSAGE 0xb0000000
630
631static void ppc64_do_msg(unsigned int src, const char *msg)
632{
633	if (ppc_md.progress) {
634		char buf[128];
635
636		sprintf(buf, "%08X\n", src);
637		ppc_md.progress(buf, 0);
638		snprintf(buf, 128, "%s", msg);
639		ppc_md.progress(buf, 0);
640	}
641}
642
643/* Print a boot progress message. */
644void ppc64_boot_msg(unsigned int src, const char *msg)
645{
646	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
647	printk("[boot]%04x %s\n", src, msg);
648}
649
650#ifdef CONFIG_SMP
651#define PCPU_DYN_SIZE		()
652
653static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
654{
655	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
656				    __pa(MAX_DMA_ADDRESS));
657}
658
659static void __init pcpu_fc_free(void *ptr, size_t size)
660{
661	free_bootmem(__pa(ptr), size);
662}
663
664static int pcpu_cpu_distance(unsigned int from, unsigned int to)
665{
666	if (cpu_to_node(from) == cpu_to_node(to))
667		return LOCAL_DISTANCE;
668	else
669		return REMOTE_DISTANCE;
670}
671
672unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
673EXPORT_SYMBOL(__per_cpu_offset);
674
675void __init setup_per_cpu_areas(void)
676{
677	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
678	size_t atom_size;
679	unsigned long delta;
680	unsigned int cpu;
681	int rc;
682
683	/*
684	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
685	 * to group units.  For larger mappings, use 1M atom which
686	 * should be large enough to contain a number of units.
687	 */
688	if (mmu_linear_psize == MMU_PAGE_4K)
689		atom_size = PAGE_SIZE;
690	else
691		atom_size = 1 << 20;
692
693	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
694				    pcpu_fc_alloc, pcpu_fc_free);
695	if (rc < 0)
696		panic("cannot initialize percpu area (err=%d)", rc);
697
698	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
699	for_each_possible_cpu(cpu) {
700                __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
701		paca[cpu].data_offset = __per_cpu_offset[cpu];
702	}
703}
704#endif
705
706
707#ifdef CONFIG_PPC_INDIRECT_IO
708struct ppc_pci_io ppc_pci_io;
709EXPORT_SYMBOL(ppc_pci_io);
710#endif /* CONFIG_PPC_INDIRECT_IO */
711
712