setup_64.c revision d715e433b7ad19c02fc4becf0d5e9a59f97925de
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 <asm/io.h>
39#include <asm/kdump.h>
40#include <asm/prom.h>
41#include <asm/processor.h>
42#include <asm/pgtable.h>
43#include <asm/smp.h>
44#include <asm/elf.h>
45#include <asm/machdep.h>
46#include <asm/paca.h>
47#include <asm/time.h>
48#include <asm/cputable.h>
49#include <asm/sections.h>
50#include <asm/btext.h>
51#include <asm/nvram.h>
52#include <asm/setup.h>
53#include <asm/system.h>
54#include <asm/rtas.h>
55#include <asm/iommu.h>
56#include <asm/serial.h>
57#include <asm/cache.h>
58#include <asm/page.h>
59#include <asm/mmu.h>
60#include <asm/firmware.h>
61#include <asm/xmon.h>
62#include <asm/udbg.h>
63#include <asm/kexec.h>
64#include <asm/mmu_context.h>
65#include <asm/code-patching.h>
66#include <asm/kvm_ppc.h>
67
68#include "setup.h"
69
70#ifdef DEBUG
71#define DBG(fmt...) udbg_printf(fmt)
72#else
73#define DBG(fmt...)
74#endif
75
76int boot_cpuid = 0;
77int __initdata spinning_secondaries;
78u64 ppc64_pft_size;
79
80/* Pick defaults since we might want to patch instructions
81 * before we've read this from the device tree.
82 */
83struct ppc64_caches ppc64_caches = {
84	.dline_size = 0x40,
85	.log_dline_size = 6,
86	.iline_size = 0x40,
87	.log_iline_size = 6
88};
89EXPORT_SYMBOL_GPL(ppc64_caches);
90
91/*
92 * These are used in binfmt_elf.c to put aux entries on the stack
93 * for each elf executable being started.
94 */
95int dcache_bsize;
96int icache_bsize;
97int ucache_bsize;
98
99#ifdef CONFIG_SMP
100
101static char *smt_enabled_cmdline;
102
103/* Look for ibm,smt-enabled OF option */
104static void check_smt_enabled(void)
105{
106	struct device_node *dn;
107	const char *smt_option;
108
109	/* Default to enabling all threads */
110	smt_enabled_at_boot = threads_per_core;
111
112	/* Allow the command line to overrule the OF option */
113	if (smt_enabled_cmdline) {
114		if (!strcmp(smt_enabled_cmdline, "on"))
115			smt_enabled_at_boot = threads_per_core;
116		else if (!strcmp(smt_enabled_cmdline, "off"))
117			smt_enabled_at_boot = 0;
118		else {
119			long smt;
120			int rc;
121
122			rc = strict_strtol(smt_enabled_cmdline, 10, &smt);
123			if (!rc)
124				smt_enabled_at_boot =
125					min(threads_per_core, (int)smt);
126		}
127	} else {
128		dn = of_find_node_by_path("/options");
129		if (dn) {
130			smt_option = of_get_property(dn, "ibm,smt-enabled",
131						     NULL);
132
133			if (smt_option) {
134				if (!strcmp(smt_option, "on"))
135					smt_enabled_at_boot = threads_per_core;
136				else if (!strcmp(smt_option, "off"))
137					smt_enabled_at_boot = 0;
138			}
139
140			of_node_put(dn);
141		}
142	}
143}
144
145/* Look for smt-enabled= cmdline option */
146static int __init early_smt_enabled(char *p)
147{
148	smt_enabled_cmdline = p;
149	return 0;
150}
151early_param("smt-enabled", early_smt_enabled);
152
153#else
154#define check_smt_enabled()
155#endif /* CONFIG_SMP */
156
157/*
158 * Early initialization entry point. This is called by head.S
159 * with MMU translation disabled. We rely on the "feature" of
160 * the CPU that ignores the top 2 bits of the address in real
161 * mode so we can access kernel globals normally provided we
162 * only toy with things in the RMO region. From here, we do
163 * some early parsing of the device-tree to setup out MEMBLOCK
164 * data structures, and allocate & initialize the hash table
165 * and segment tables so we can start running with translation
166 * enabled.
167 *
168 * It is this function which will call the probe() callback of
169 * the various platform types and copy the matching one to the
170 * global ppc_md structure. Your platform can eventually do
171 * some very early initializations from the probe() routine, but
172 * this is not recommended, be very careful as, for example, the
173 * device-tree is not accessible via normal means at this point.
174 */
175
176void __init early_setup(unsigned long dt_ptr)
177{
178	/* -------- printk is _NOT_ safe to use here ! ------- */
179
180	/* Identify CPU type */
181	identify_cpu(0, mfspr(SPRN_PVR));
182
183	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
184	initialise_paca(&boot_paca, 0);
185	setup_paca(&boot_paca);
186
187	/* Initialize lockdep early or else spinlocks will blow */
188	lockdep_init();
189
190	/* -------- printk is now safe to use ------- */
191
192	/* Enable early debugging if any specified (see udbg.h) */
193	udbg_early_init();
194
195 	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
196
197	/*
198	 * Do early initialization using the flattened device
199	 * tree, such as retrieving the physical memory map or
200	 * calculating/retrieving the hash table size.
201	 */
202	early_init_devtree(__va(dt_ptr));
203
204	/* Now we know the logical id of our boot cpu, setup the paca. */
205	setup_paca(&paca[boot_cpuid]);
206
207	/* Fix up paca fields required for the boot cpu */
208	get_paca()->cpu_start = 1;
209
210	/* Probe the machine type */
211	probe_machine();
212
213	setup_kdump_trampoline();
214
215	DBG("Found, Initializing memory management...\n");
216
217	/* Initialize the hash table or TLB handling */
218	early_init_mmu();
219
220	DBG(" <- early_setup()\n");
221}
222
223#ifdef CONFIG_SMP
224void early_setup_secondary(void)
225{
226	/* Mark interrupts enabled in PACA */
227	get_paca()->soft_enabled = 0;
228
229	/* Initialize the hash table or TLB handling */
230	early_init_mmu_secondary();
231}
232
233#endif /* CONFIG_SMP */
234
235#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
236void smp_release_cpus(void)
237{
238	unsigned long *ptr;
239	int i;
240
241	DBG(" -> smp_release_cpus()\n");
242
243	/* All secondary cpus are spinning on a common spinloop, release them
244	 * all now so they can start to spin on their individual paca
245	 * spinloops. For non SMP kernels, the secondary cpus never get out
246	 * of the common spinloop.
247	 */
248
249	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
250			- PHYSICAL_START);
251	*ptr = __pa(generic_secondary_smp_init);
252
253	/* And wait a bit for them to catch up */
254	for (i = 0; i < 100000; i++) {
255		mb();
256		HMT_low();
257		if (spinning_secondaries == 0)
258			break;
259		udelay(1);
260	}
261	DBG("spinning_secondaries = %d\n", spinning_secondaries);
262
263	DBG(" <- smp_release_cpus()\n");
264}
265#endif /* CONFIG_SMP || CONFIG_KEXEC */
266
267/*
268 * Initialize some remaining members of the ppc64_caches and systemcfg
269 * structures
270 * (at least until we get rid of them completely). This is mostly some
271 * cache informations about the CPU that will be used by cache flush
272 * routines and/or provided to userland
273 */
274static void __init initialize_cache_info(void)
275{
276	struct device_node *np;
277	unsigned long num_cpus = 0;
278
279	DBG(" -> initialize_cache_info()\n");
280
281	for_each_node_by_type(np, "cpu") {
282		num_cpus += 1;
283
284		/*
285		 * We're assuming *all* of the CPUs have the same
286		 * d-cache and i-cache sizes... -Peter
287		 */
288		if (num_cpus == 1) {
289			const u32 *sizep, *lsizep;
290			u32 size, lsize;
291
292			size = 0;
293			lsize = cur_cpu_spec->dcache_bsize;
294			sizep = of_get_property(np, "d-cache-size", NULL);
295			if (sizep != NULL)
296				size = *sizep;
297			lsizep = of_get_property(np, "d-cache-block-size",
298						 NULL);
299			/* fallback if block size missing */
300			if (lsizep == NULL)
301				lsizep = of_get_property(np,
302							 "d-cache-line-size",
303							 NULL);
304			if (lsizep != NULL)
305				lsize = *lsizep;
306			if (sizep == 0 || lsizep == 0)
307				DBG("Argh, can't find dcache properties ! "
308				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
309
310			ppc64_caches.dsize = size;
311			ppc64_caches.dline_size = lsize;
312			ppc64_caches.log_dline_size = __ilog2(lsize);
313			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
314
315			size = 0;
316			lsize = cur_cpu_spec->icache_bsize;
317			sizep = of_get_property(np, "i-cache-size", NULL);
318			if (sizep != NULL)
319				size = *sizep;
320			lsizep = of_get_property(np, "i-cache-block-size",
321						 NULL);
322			if (lsizep == NULL)
323				lsizep = of_get_property(np,
324							 "i-cache-line-size",
325							 NULL);
326			if (lsizep != NULL)
327				lsize = *lsizep;
328			if (sizep == 0 || lsizep == 0)
329				DBG("Argh, can't find icache properties ! "
330				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
331
332			ppc64_caches.isize = size;
333			ppc64_caches.iline_size = lsize;
334			ppc64_caches.log_iline_size = __ilog2(lsize);
335			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
336		}
337	}
338
339	DBG(" <- initialize_cache_info()\n");
340}
341
342
343/*
344 * Do some initial setup of the system.  The parameters are those which
345 * were passed in from the bootloader.
346 */
347void __init setup_system(void)
348{
349	DBG(" -> setup_system()\n");
350
351	/* Apply the CPUs-specific and firmware specific fixups to kernel
352	 * text (nop out sections not relevant to this CPU or this firmware)
353	 */
354	do_feature_fixups(cur_cpu_spec->cpu_features,
355			  &__start___ftr_fixup, &__stop___ftr_fixup);
356	do_feature_fixups(cur_cpu_spec->mmu_features,
357			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
358	do_feature_fixups(powerpc_firmware_features,
359			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
360	do_lwsync_fixups(cur_cpu_spec->cpu_features,
361			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
362	do_final_fixups();
363
364	/*
365	 * Unflatten the device-tree passed by prom_init or kexec
366	 */
367	unflatten_device_tree();
368
369	/*
370	 * Fill the ppc64_caches & systemcfg structures with informations
371 	 * retrieved from the device-tree.
372	 */
373	initialize_cache_info();
374
375#ifdef CONFIG_PPC_RTAS
376	/*
377	 * Initialize RTAS if available
378	 */
379	rtas_initialize();
380#endif /* CONFIG_PPC_RTAS */
381
382	/*
383	 * Check if we have an initrd provided via the device-tree
384	 */
385	check_for_initrd();
386
387	/*
388	 * Do some platform specific early initializations, that includes
389	 * setting up the hash table pointers. It also sets up some interrupt-mapping
390	 * related options that will be used by finish_device_tree()
391	 */
392	if (ppc_md.init_early)
393		ppc_md.init_early();
394
395 	/*
396	 * We can discover serial ports now since the above did setup the
397	 * hash table management for us, thus ioremap works. We do that early
398	 * so that further code can be debugged
399	 */
400	find_legacy_serial_ports();
401
402	/*
403	 * Register early console
404	 */
405	register_early_udbg_console();
406
407	/*
408	 * Initialize xmon
409	 */
410	xmon_setup();
411
412	smp_setup_cpu_maps();
413	check_smt_enabled();
414
415#ifdef CONFIG_SMP
416	/* Release secondary cpus out of their spinloops at 0x60 now that
417	 * we can map physical -> logical CPU ids
418	 */
419	smp_release_cpus();
420#endif
421
422	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
423
424	printk("-----------------------------------------------------\n");
425	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
426	printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
427	if (ppc64_caches.dline_size != 0x80)
428		printk("ppc64_caches.dcache_line_size = 0x%x\n",
429		       ppc64_caches.dline_size);
430	if (ppc64_caches.iline_size != 0x80)
431		printk("ppc64_caches.icache_line_size = 0x%x\n",
432		       ppc64_caches.iline_size);
433#ifdef CONFIG_PPC_STD_MMU_64
434	if (htab_address)
435		printk("htab_address                  = 0x%p\n", htab_address);
436	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
437#endif /* CONFIG_PPC_STD_MMU_64 */
438	if (PHYSICAL_START > 0)
439		printk("physical_start                = 0x%llx\n",
440		       (unsigned long long)PHYSICAL_START);
441	printk("-----------------------------------------------------\n");
442
443	DBG(" <- setup_system()\n");
444}
445
446/* This returns the limit below which memory accesses to the linear
447 * mapping are guarnateed not to cause a TLB or SLB miss. This is
448 * used to allocate interrupt or emergency stacks for which our
449 * exception entry path doesn't deal with being interrupted.
450 */
451static u64 safe_stack_limit(void)
452{
453#ifdef CONFIG_PPC_BOOK3E
454	/* Freescale BookE bolts the entire linear mapping */
455	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
456		return linear_map_top;
457	/* Other BookE, we assume the first GB is bolted */
458	return 1ul << 30;
459#else
460	/* BookS, the first segment is bolted */
461	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
462		return 1UL << SID_SHIFT_1T;
463	return 1UL << SID_SHIFT;
464#endif
465}
466
467static void __init irqstack_early_init(void)
468{
469	u64 limit = safe_stack_limit();
470	unsigned int i;
471
472	/*
473	 * Interrupt stacks must be in the first segment since we
474	 * cannot afford to take SLB misses on them.
475	 */
476	for_each_possible_cpu(i) {
477		softirq_ctx[i] = (struct thread_info *)
478			__va(memblock_alloc_base(THREAD_SIZE,
479					    THREAD_SIZE, limit));
480		hardirq_ctx[i] = (struct thread_info *)
481			__va(memblock_alloc_base(THREAD_SIZE,
482					    THREAD_SIZE, limit));
483	}
484}
485
486#ifdef CONFIG_PPC_BOOK3E
487static void __init exc_lvl_early_init(void)
488{
489	extern unsigned int interrupt_base_book3e;
490	extern unsigned int exc_debug_debug_book3e;
491
492	unsigned int i;
493
494	for_each_possible_cpu(i) {
495		critirq_ctx[i] = (struct thread_info *)
496			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
497		dbgirq_ctx[i] = (struct thread_info *)
498			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
499		mcheckirq_ctx[i] = (struct thread_info *)
500			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
501	}
502
503	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
504		patch_branch(&interrupt_base_book3e + (0x040 / 4) + 1,
505			     (unsigned long)&exc_debug_debug_book3e, 0);
506}
507#else
508#define exc_lvl_early_init()
509#endif
510
511/*
512 * Stack space used when we detect a bad kernel stack pointer, and
513 * early in SMP boots before relocation is enabled.
514 */
515static void __init emergency_stack_init(void)
516{
517	u64 limit;
518	unsigned int i;
519
520	/*
521	 * Emergency stacks must be under 256MB, we cannot afford to take
522	 * SLB misses on them. The ABI also requires them to be 128-byte
523	 * aligned.
524	 *
525	 * Since we use these as temporary stacks during secondary CPU
526	 * bringup, we need to get at them in real mode. This means they
527	 * must also be within the RMO region.
528	 */
529	limit = min(safe_stack_limit(), ppc64_rma_size);
530
531	for_each_possible_cpu(i) {
532		unsigned long sp;
533		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
534		sp += THREAD_SIZE;
535		paca[i].emergency_sp = __va(sp);
536	}
537}
538
539/*
540 * Called into from start_kernel this initializes bootmem, which is used
541 * to manage page allocation until mem_init is called.
542 */
543void __init setup_arch(char **cmdline_p)
544{
545	ppc64_boot_msg(0x12, "Setup Arch");
546
547	*cmdline_p = cmd_line;
548
549	/*
550	 * Set cache line size based on type of cpu as a default.
551	 * Systems with OF can look in the properties on the cpu node(s)
552	 * for a possibly more accurate value.
553	 */
554	dcache_bsize = ppc64_caches.dline_size;
555	icache_bsize = ppc64_caches.iline_size;
556
557	/* reboot on panic */
558	panic_timeout = 180;
559
560	if (ppc_md.panic)
561		setup_panic();
562
563	init_mm.start_code = (unsigned long)_stext;
564	init_mm.end_code = (unsigned long) _etext;
565	init_mm.end_data = (unsigned long) _edata;
566	init_mm.brk = klimit;
567
568	irqstack_early_init();
569	exc_lvl_early_init();
570	emergency_stack_init();
571
572#ifdef CONFIG_PPC_STD_MMU_64
573	stabs_alloc();
574#endif
575	/* set up the bootmem stuff with available memory */
576	do_init_bootmem();
577	sparse_init();
578
579#ifdef CONFIG_DUMMY_CONSOLE
580	conswitchp = &dummy_con;
581#endif
582
583	if (ppc_md.setup_arch)
584		ppc_md.setup_arch();
585
586	paging_init();
587
588	/* Initialize the MMU context management stuff */
589	mmu_context_init();
590
591	kvm_rma_init();
592
593	ppc64_boot_msg(0x15, "Setup Done");
594}
595
596
597/* ToDo: do something useful if ppc_md is not yet setup. */
598#define PPC64_LINUX_FUNCTION 0x0f000000
599#define PPC64_IPL_MESSAGE 0xc0000000
600#define PPC64_TERM_MESSAGE 0xb0000000
601
602static void ppc64_do_msg(unsigned int src, const char *msg)
603{
604	if (ppc_md.progress) {
605		char buf[128];
606
607		sprintf(buf, "%08X\n", src);
608		ppc_md.progress(buf, 0);
609		snprintf(buf, 128, "%s", msg);
610		ppc_md.progress(buf, 0);
611	}
612}
613
614/* Print a boot progress message. */
615void ppc64_boot_msg(unsigned int src, const char *msg)
616{
617	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
618	printk("[boot]%04x %s\n", src, msg);
619}
620
621#ifdef CONFIG_SMP
622#define PCPU_DYN_SIZE		()
623
624static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
625{
626	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
627				    __pa(MAX_DMA_ADDRESS));
628}
629
630static void __init pcpu_fc_free(void *ptr, size_t size)
631{
632	free_bootmem(__pa(ptr), size);
633}
634
635static int pcpu_cpu_distance(unsigned int from, unsigned int to)
636{
637	if (cpu_to_node(from) == cpu_to_node(to))
638		return LOCAL_DISTANCE;
639	else
640		return REMOTE_DISTANCE;
641}
642
643unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
644EXPORT_SYMBOL(__per_cpu_offset);
645
646void __init setup_per_cpu_areas(void)
647{
648	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
649	size_t atom_size;
650	unsigned long delta;
651	unsigned int cpu;
652	int rc;
653
654	/*
655	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
656	 * to group units.  For larger mappings, use 1M atom which
657	 * should be large enough to contain a number of units.
658	 */
659	if (mmu_linear_psize == MMU_PAGE_4K)
660		atom_size = PAGE_SIZE;
661	else
662		atom_size = 1 << 20;
663
664	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
665				    pcpu_fc_alloc, pcpu_fc_free);
666	if (rc < 0)
667		panic("cannot initialize percpu area (err=%d)", rc);
668
669	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
670	for_each_possible_cpu(cpu) {
671                __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
672		paca[cpu].data_offset = __per_cpu_offset[cpu];
673	}
674}
675#endif
676
677
678#ifdef CONFIG_PPC_INDIRECT_IO
679struct ppc_pci_io ppc_pci_io;
680EXPORT_SYMBOL(ppc_pci_io);
681#endif /* CONFIG_PPC_INDIRECT_IO */
682
683