setup_64.c revision 5c1f6ee9a31cbdac90bbb8ae1ba4475031ac74b4
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
70#include "setup.h"
71
72#ifdef DEBUG
73#define DBG(fmt...) udbg_printf(fmt)
74#else
75#define DBG(fmt...)
76#endif
77
78int boot_cpuid = 0;
79int __initdata 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#ifdef CONFIG_SMP
102
103static char *smt_enabled_cmdline;
104
105/* Look for ibm,smt-enabled OF option */
106static void check_smt_enabled(void)
107{
108	struct device_node *dn;
109	const char *smt_option;
110
111	/* Default to enabling all threads */
112	smt_enabled_at_boot = threads_per_core;
113
114	/* Allow the command line to overrule the OF option */
115	if (smt_enabled_cmdline) {
116		if (!strcmp(smt_enabled_cmdline, "on"))
117			smt_enabled_at_boot = threads_per_core;
118		else if (!strcmp(smt_enabled_cmdline, "off"))
119			smt_enabled_at_boot = 0;
120		else {
121			long smt;
122			int rc;
123
124			rc = strict_strtol(smt_enabled_cmdline, 10, &smt);
125			if (!rc)
126				smt_enabled_at_boot =
127					min(threads_per_core, (int)smt);
128		}
129	} else {
130		dn = of_find_node_by_path("/options");
131		if (dn) {
132			smt_option = of_get_property(dn, "ibm,smt-enabled",
133						     NULL);
134
135			if (smt_option) {
136				if (!strcmp(smt_option, "on"))
137					smt_enabled_at_boot = threads_per_core;
138				else if (!strcmp(smt_option, "off"))
139					smt_enabled_at_boot = 0;
140			}
141
142			of_node_put(dn);
143		}
144	}
145}
146
147/* Look for smt-enabled= cmdline option */
148static int __init early_smt_enabled(char *p)
149{
150	smt_enabled_cmdline = p;
151	return 0;
152}
153early_param("smt-enabled", early_smt_enabled);
154
155#else
156#define check_smt_enabled()
157#endif /* CONFIG_SMP */
158
159/** Fix up paca fields required for the boot cpu */
160static void fixup_boot_paca(void)
161{
162	/* The boot cpu is started */
163	get_paca()->cpu_start = 1;
164	/* Allow percpu accesses to work until we setup percpu data */
165	get_paca()->data_offset = 0;
166}
167
168/*
169 * Early initialization entry point. This is called by head.S
170 * with MMU translation disabled. We rely on the "feature" of
171 * the CPU that ignores the top 2 bits of the address in real
172 * mode so we can access kernel globals normally provided we
173 * only toy with things in the RMO region. From here, we do
174 * some early parsing of the device-tree to setup out MEMBLOCK
175 * data structures, and allocate & initialize the hash table
176 * and segment tables so we can start running with translation
177 * enabled.
178 *
179 * It is this function which will call the probe() callback of
180 * the various platform types and copy the matching one to the
181 * global ppc_md structure. Your platform can eventually do
182 * some very early initializations from the probe() routine, but
183 * this is not recommended, be very careful as, for example, the
184 * device-tree is not accessible via normal means at this point.
185 */
186
187void __init early_setup(unsigned long dt_ptr)
188{
189	static __initdata struct paca_struct boot_paca;
190
191	/* -------- printk is _NOT_ safe to use here ! ------- */
192
193	/* Identify CPU type */
194	identify_cpu(0, mfspr(SPRN_PVR));
195
196	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
197	initialise_paca(&boot_paca, 0);
198	setup_paca(&boot_paca);
199	fixup_boot_paca();
200
201	/* Initialize lockdep early or else spinlocks will blow */
202	lockdep_init();
203
204	/* -------- printk is now safe to use ------- */
205
206	/* Enable early debugging if any specified (see udbg.h) */
207	udbg_early_init();
208
209 	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
210
211	/*
212	 * Do early initialization using the flattened device
213	 * tree, such as retrieving the physical memory map or
214	 * calculating/retrieving the hash table size.
215	 */
216	early_init_devtree(__va(dt_ptr));
217
218	/* Now we know the logical id of our boot cpu, setup the paca. */
219	setup_paca(&paca[boot_cpuid]);
220	fixup_boot_paca();
221
222	/* Probe the machine type */
223	probe_machine();
224
225	setup_kdump_trampoline();
226
227	DBG("Found, Initializing memory management...\n");
228
229	/* Initialize the hash table or TLB handling */
230	early_init_mmu();
231
232	/*
233	 * Reserve any gigantic pages requested on the command line.
234	 * memblock needs to have been initialized by the time this is
235	 * called since this will reserve memory.
236	 */
237	reserve_hugetlb_gpages();
238
239	DBG(" <- early_setup()\n");
240}
241
242#ifdef CONFIG_SMP
243void early_setup_secondary(void)
244{
245	/* Mark interrupts enabled in PACA */
246	get_paca()->soft_enabled = 0;
247
248	/* Initialize the hash table or TLB handling */
249	early_init_mmu_secondary();
250}
251
252#endif /* CONFIG_SMP */
253
254#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
255void smp_release_cpus(void)
256{
257	unsigned long *ptr;
258	int i;
259
260	DBG(" -> smp_release_cpus()\n");
261
262	/* All secondary cpus are spinning on a common spinloop, release them
263	 * all now so they can start to spin on their individual paca
264	 * spinloops. For non SMP kernels, the secondary cpus never get out
265	 * of the common spinloop.
266	 */
267
268	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
269			- PHYSICAL_START);
270	*ptr = __pa(generic_secondary_smp_init);
271
272	/* And wait a bit for them to catch up */
273	for (i = 0; i < 100000; i++) {
274		mb();
275		HMT_low();
276		if (spinning_secondaries == 0)
277			break;
278		udelay(1);
279	}
280	DBG("spinning_secondaries = %d\n", spinning_secondaries);
281
282	DBG(" <- smp_release_cpus()\n");
283}
284#endif /* CONFIG_SMP || CONFIG_KEXEC */
285
286/*
287 * Initialize some remaining members of the ppc64_caches and systemcfg
288 * structures
289 * (at least until we get rid of them completely). This is mostly some
290 * cache informations about the CPU that will be used by cache flush
291 * routines and/or provided to userland
292 */
293static void __init initialize_cache_info(void)
294{
295	struct device_node *np;
296	unsigned long num_cpus = 0;
297
298	DBG(" -> initialize_cache_info()\n");
299
300	for_each_node_by_type(np, "cpu") {
301		num_cpus += 1;
302
303		/*
304		 * We're assuming *all* of the CPUs have the same
305		 * d-cache and i-cache sizes... -Peter
306		 */
307		if (num_cpus == 1) {
308			const u32 *sizep, *lsizep;
309			u32 size, lsize;
310
311			size = 0;
312			lsize = cur_cpu_spec->dcache_bsize;
313			sizep = of_get_property(np, "d-cache-size", NULL);
314			if (sizep != NULL)
315				size = *sizep;
316			lsizep = of_get_property(np, "d-cache-block-size",
317						 NULL);
318			/* fallback if block size missing */
319			if (lsizep == NULL)
320				lsizep = of_get_property(np,
321							 "d-cache-line-size",
322							 NULL);
323			if (lsizep != NULL)
324				lsize = *lsizep;
325			if (sizep == 0 || lsizep == 0)
326				DBG("Argh, can't find dcache properties ! "
327				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
328
329			ppc64_caches.dsize = size;
330			ppc64_caches.dline_size = lsize;
331			ppc64_caches.log_dline_size = __ilog2(lsize);
332			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
333
334			size = 0;
335			lsize = cur_cpu_spec->icache_bsize;
336			sizep = of_get_property(np, "i-cache-size", NULL);
337			if (sizep != NULL)
338				size = *sizep;
339			lsizep = of_get_property(np, "i-cache-block-size",
340						 NULL);
341			if (lsizep == NULL)
342				lsizep = of_get_property(np,
343							 "i-cache-line-size",
344							 NULL);
345			if (lsizep != NULL)
346				lsize = *lsizep;
347			if (sizep == 0 || lsizep == 0)
348				DBG("Argh, can't find icache properties ! "
349				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
350
351			ppc64_caches.isize = size;
352			ppc64_caches.iline_size = lsize;
353			ppc64_caches.log_iline_size = __ilog2(lsize);
354			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
355		}
356	}
357
358	DBG(" <- initialize_cache_info()\n");
359}
360
361
362/*
363 * Do some initial setup of the system.  The parameters are those which
364 * were passed in from the bootloader.
365 */
366void __init setup_system(void)
367{
368	DBG(" -> setup_system()\n");
369
370	/* Apply the CPUs-specific and firmware specific fixups to kernel
371	 * text (nop out sections not relevant to this CPU or this firmware)
372	 */
373	do_feature_fixups(cur_cpu_spec->cpu_features,
374			  &__start___ftr_fixup, &__stop___ftr_fixup);
375	do_feature_fixups(cur_cpu_spec->mmu_features,
376			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
377	do_feature_fixups(powerpc_firmware_features,
378			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
379	do_lwsync_fixups(cur_cpu_spec->cpu_features,
380			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
381	do_final_fixups();
382
383	/*
384	 * Unflatten the device-tree passed by prom_init or kexec
385	 */
386	unflatten_device_tree();
387
388	/*
389	 * Fill the ppc64_caches & systemcfg structures with informations
390 	 * retrieved from the device-tree.
391	 */
392	initialize_cache_info();
393
394#ifdef CONFIG_PPC_RTAS
395	/*
396	 * Initialize RTAS if available
397	 */
398	rtas_initialize();
399#endif /* CONFIG_PPC_RTAS */
400
401	/*
402	 * Check if we have an initrd provided via the device-tree
403	 */
404	check_for_initrd();
405
406	/*
407	 * Do some platform specific early initializations, that includes
408	 * setting up the hash table pointers. It also sets up some interrupt-mapping
409	 * related options that will be used by finish_device_tree()
410	 */
411	if (ppc_md.init_early)
412		ppc_md.init_early();
413
414 	/*
415	 * We can discover serial ports now since the above did setup the
416	 * hash table management for us, thus ioremap works. We do that early
417	 * so that further code can be debugged
418	 */
419	find_legacy_serial_ports();
420
421	/*
422	 * Register early console
423	 */
424	register_early_udbg_console();
425
426	/*
427	 * Initialize xmon
428	 */
429	xmon_setup();
430
431	smp_setup_cpu_maps();
432	check_smt_enabled();
433
434#ifdef CONFIG_SMP
435	/* Release secondary cpus out of their spinloops at 0x60 now that
436	 * we can map physical -> logical CPU ids
437	 */
438	smp_release_cpus();
439#endif
440
441	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
442
443	printk("-----------------------------------------------------\n");
444	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
445	printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
446	if (ppc64_caches.dline_size != 0x80)
447		printk("ppc64_caches.dcache_line_size = 0x%x\n",
448		       ppc64_caches.dline_size);
449	if (ppc64_caches.iline_size != 0x80)
450		printk("ppc64_caches.icache_line_size = 0x%x\n",
451		       ppc64_caches.iline_size);
452#ifdef CONFIG_PPC_STD_MMU_64
453	if (htab_address)
454		printk("htab_address                  = 0x%p\n", htab_address);
455	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
456#endif /* CONFIG_PPC_STD_MMU_64 */
457	if (PHYSICAL_START > 0)
458		printk("physical_start                = 0x%llx\n",
459		       (unsigned long long)PHYSICAL_START);
460	printk("-----------------------------------------------------\n");
461
462	DBG(" <- setup_system()\n");
463}
464
465/* This returns the limit below which memory accesses to the linear
466 * mapping are guarnateed not to cause a TLB or SLB miss. This is
467 * used to allocate interrupt or emergency stacks for which our
468 * exception entry path doesn't deal with being interrupted.
469 */
470static u64 safe_stack_limit(void)
471{
472#ifdef CONFIG_PPC_BOOK3E
473	/* Freescale BookE bolts the entire linear mapping */
474	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
475		return linear_map_top;
476	/* Other BookE, we assume the first GB is bolted */
477	return 1ul << 30;
478#else
479	/* BookS, the first segment is bolted */
480	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
481		return 1UL << SID_SHIFT_1T;
482	return 1UL << SID_SHIFT;
483#endif
484}
485
486static void __init irqstack_early_init(void)
487{
488	u64 limit = safe_stack_limit();
489	unsigned int i;
490
491	/*
492	 * Interrupt stacks must be in the first segment since we
493	 * cannot afford to take SLB misses on them.
494	 */
495	for_each_possible_cpu(i) {
496		softirq_ctx[i] = (struct thread_info *)
497			__va(memblock_alloc_base(THREAD_SIZE,
498					    THREAD_SIZE, limit));
499		hardirq_ctx[i] = (struct thread_info *)
500			__va(memblock_alloc_base(THREAD_SIZE,
501					    THREAD_SIZE, limit));
502	}
503}
504
505#ifdef CONFIG_PPC_BOOK3E
506static void __init exc_lvl_early_init(void)
507{
508	extern unsigned int interrupt_base_book3e;
509	extern unsigned int exc_debug_debug_book3e;
510
511	unsigned int i;
512
513	for_each_possible_cpu(i) {
514		critirq_ctx[i] = (struct thread_info *)
515			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
516		dbgirq_ctx[i] = (struct thread_info *)
517			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
518		mcheckirq_ctx[i] = (struct thread_info *)
519			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
520	}
521
522	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
523		patch_branch(&interrupt_base_book3e + (0x040 / 4) + 1,
524			     (unsigned long)&exc_debug_debug_book3e, 0);
525}
526#else
527#define exc_lvl_early_init()
528#endif
529
530/*
531 * Stack space used when we detect a bad kernel stack pointer, and
532 * early in SMP boots before relocation is enabled.
533 */
534static void __init emergency_stack_init(void)
535{
536	u64 limit;
537	unsigned int i;
538
539	/*
540	 * Emergency stacks must be under 256MB, we cannot afford to take
541	 * SLB misses on them. The ABI also requires them to be 128-byte
542	 * aligned.
543	 *
544	 * Since we use these as temporary stacks during secondary CPU
545	 * bringup, we need to get at them in real mode. This means they
546	 * must also be within the RMO region.
547	 */
548	limit = min(safe_stack_limit(), ppc64_rma_size);
549
550	for_each_possible_cpu(i) {
551		unsigned long sp;
552		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
553		sp += THREAD_SIZE;
554		paca[i].emergency_sp = __va(sp);
555	}
556}
557
558/*
559 * Called into from start_kernel this initializes bootmem, which is used
560 * to manage page allocation until mem_init is called.
561 */
562void __init setup_arch(char **cmdline_p)
563{
564	ppc64_boot_msg(0x12, "Setup Arch");
565
566	*cmdline_p = cmd_line;
567
568	/*
569	 * Set cache line size based on type of cpu as a default.
570	 * Systems with OF can look in the properties on the cpu node(s)
571	 * for a possibly more accurate value.
572	 */
573	dcache_bsize = ppc64_caches.dline_size;
574	icache_bsize = ppc64_caches.iline_size;
575
576	/* reboot on panic */
577	panic_timeout = 180;
578
579	if (ppc_md.panic)
580		setup_panic();
581
582	init_mm.start_code = (unsigned long)_stext;
583	init_mm.end_code = (unsigned long) _etext;
584	init_mm.end_data = (unsigned long) _edata;
585	init_mm.brk = klimit;
586#ifdef CONFIG_PPC_64K_PAGES
587	init_mm.context.pte_frag = NULL;
588#endif
589	irqstack_early_init();
590	exc_lvl_early_init();
591	emergency_stack_init();
592
593#ifdef CONFIG_PPC_STD_MMU_64
594	stabs_alloc();
595#endif
596	/* set up the bootmem stuff with available memory */
597	do_init_bootmem();
598	sparse_init();
599
600#ifdef CONFIG_DUMMY_CONSOLE
601	conswitchp = &dummy_con;
602#endif
603
604	if (ppc_md.setup_arch)
605		ppc_md.setup_arch();
606
607	paging_init();
608
609	/* Initialize the MMU context management stuff */
610	mmu_context_init();
611
612	kvm_linear_init();
613
614	/* Interrupt code needs to be 64K-aligned */
615	if ((unsigned long)_stext & 0xffff)
616		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
617		      (unsigned long)_stext);
618
619	ppc64_boot_msg(0x15, "Setup Done");
620}
621
622
623/* ToDo: do something useful if ppc_md is not yet setup. */
624#define PPC64_LINUX_FUNCTION 0x0f000000
625#define PPC64_IPL_MESSAGE 0xc0000000
626#define PPC64_TERM_MESSAGE 0xb0000000
627
628static void ppc64_do_msg(unsigned int src, const char *msg)
629{
630	if (ppc_md.progress) {
631		char buf[128];
632
633		sprintf(buf, "%08X\n", src);
634		ppc_md.progress(buf, 0);
635		snprintf(buf, 128, "%s", msg);
636		ppc_md.progress(buf, 0);
637	}
638}
639
640/* Print a boot progress message. */
641void ppc64_boot_msg(unsigned int src, const char *msg)
642{
643	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
644	printk("[boot]%04x %s\n", src, msg);
645}
646
647#ifdef CONFIG_SMP
648#define PCPU_DYN_SIZE		()
649
650static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
651{
652	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
653				    __pa(MAX_DMA_ADDRESS));
654}
655
656static void __init pcpu_fc_free(void *ptr, size_t size)
657{
658	free_bootmem(__pa(ptr), size);
659}
660
661static int pcpu_cpu_distance(unsigned int from, unsigned int to)
662{
663	if (cpu_to_node(from) == cpu_to_node(to))
664		return LOCAL_DISTANCE;
665	else
666		return REMOTE_DISTANCE;
667}
668
669unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
670EXPORT_SYMBOL(__per_cpu_offset);
671
672void __init setup_per_cpu_areas(void)
673{
674	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
675	size_t atom_size;
676	unsigned long delta;
677	unsigned int cpu;
678	int rc;
679
680	/*
681	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
682	 * to group units.  For larger mappings, use 1M atom which
683	 * should be large enough to contain a number of units.
684	 */
685	if (mmu_linear_psize == MMU_PAGE_4K)
686		atom_size = PAGE_SIZE;
687	else
688		atom_size = 1 << 20;
689
690	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
691				    pcpu_fc_alloc, pcpu_fc_free);
692	if (rc < 0)
693		panic("cannot initialize percpu area (err=%d)", rc);
694
695	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
696	for_each_possible_cpu(cpu) {
697                __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
698		paca[cpu].data_offset = __per_cpu_offset[cpu];
699	}
700}
701#endif
702
703
704#ifdef CONFIG_PPC_INDIRECT_IO
705struct ppc_pci_io ppc_pci_io;
706EXPORT_SYMBOL(ppc_pci_io);
707#endif /* CONFIG_PPC_INDIRECT_IO */
708
709