setup_64.c revision fa61a4e376d2129690c82dfb05b31705a67d6e0b
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	kvm_cma_reserve();
233
234	/*
235	 * Reserve any gigantic pages requested on the command line.
236	 * memblock needs to have been initialized by the time this is
237	 * called since this will reserve memory.
238	 */
239	reserve_hugetlb_gpages();
240
241	DBG(" <- early_setup()\n");
242}
243
244#ifdef CONFIG_SMP
245void early_setup_secondary(void)
246{
247	/* Mark interrupts enabled in PACA */
248	get_paca()->soft_enabled = 0;
249
250	/* Initialize the hash table or TLB handling */
251	early_init_mmu_secondary();
252}
253
254#endif /* CONFIG_SMP */
255
256#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
257void smp_release_cpus(void)
258{
259	unsigned long *ptr;
260	int i;
261
262	DBG(" -> smp_release_cpus()\n");
263
264	/* All secondary cpus are spinning on a common spinloop, release them
265	 * all now so they can start to spin on their individual paca
266	 * spinloops. For non SMP kernels, the secondary cpus never get out
267	 * of the common spinloop.
268	 */
269
270	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
271			- PHYSICAL_START);
272	*ptr = __pa(generic_secondary_smp_init);
273
274	/* And wait a bit for them to catch up */
275	for (i = 0; i < 100000; i++) {
276		mb();
277		HMT_low();
278		if (spinning_secondaries == 0)
279			break;
280		udelay(1);
281	}
282	DBG("spinning_secondaries = %d\n", spinning_secondaries);
283
284	DBG(" <- smp_release_cpus()\n");
285}
286#endif /* CONFIG_SMP || CONFIG_KEXEC */
287
288/*
289 * Initialize some remaining members of the ppc64_caches and systemcfg
290 * structures
291 * (at least until we get rid of them completely). This is mostly some
292 * cache informations about the CPU that will be used by cache flush
293 * routines and/or provided to userland
294 */
295static void __init initialize_cache_info(void)
296{
297	struct device_node *np;
298	unsigned long num_cpus = 0;
299
300	DBG(" -> initialize_cache_info()\n");
301
302	for_each_node_by_type(np, "cpu") {
303		num_cpus += 1;
304
305		/*
306		 * We're assuming *all* of the CPUs have the same
307		 * d-cache and i-cache sizes... -Peter
308		 */
309		if (num_cpus == 1) {
310			const u32 *sizep, *lsizep;
311			u32 size, lsize;
312
313			size = 0;
314			lsize = cur_cpu_spec->dcache_bsize;
315			sizep = of_get_property(np, "d-cache-size", NULL);
316			if (sizep != NULL)
317				size = *sizep;
318			lsizep = of_get_property(np, "d-cache-block-size",
319						 NULL);
320			/* fallback if block size missing */
321			if (lsizep == NULL)
322				lsizep = of_get_property(np,
323							 "d-cache-line-size",
324							 NULL);
325			if (lsizep != NULL)
326				lsize = *lsizep;
327			if (sizep == 0 || lsizep == 0)
328				DBG("Argh, can't find dcache properties ! "
329				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
330
331			ppc64_caches.dsize = size;
332			ppc64_caches.dline_size = lsize;
333			ppc64_caches.log_dline_size = __ilog2(lsize);
334			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
335
336			size = 0;
337			lsize = cur_cpu_spec->icache_bsize;
338			sizep = of_get_property(np, "i-cache-size", NULL);
339			if (sizep != NULL)
340				size = *sizep;
341			lsizep = of_get_property(np, "i-cache-block-size",
342						 NULL);
343			if (lsizep == NULL)
344				lsizep = of_get_property(np,
345							 "i-cache-line-size",
346							 NULL);
347			if (lsizep != NULL)
348				lsize = *lsizep;
349			if (sizep == 0 || lsizep == 0)
350				DBG("Argh, can't find icache properties ! "
351				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
352
353			ppc64_caches.isize = size;
354			ppc64_caches.iline_size = lsize;
355			ppc64_caches.log_iline_size = __ilog2(lsize);
356			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
357		}
358	}
359
360	DBG(" <- initialize_cache_info()\n");
361}
362
363
364/*
365 * Do some initial setup of the system.  The parameters are those which
366 * were passed in from the bootloader.
367 */
368void __init setup_system(void)
369{
370	DBG(" -> setup_system()\n");
371
372	/* Apply the CPUs-specific and firmware specific fixups to kernel
373	 * text (nop out sections not relevant to this CPU or this firmware)
374	 */
375	do_feature_fixups(cur_cpu_spec->cpu_features,
376			  &__start___ftr_fixup, &__stop___ftr_fixup);
377	do_feature_fixups(cur_cpu_spec->mmu_features,
378			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
379	do_feature_fixups(powerpc_firmware_features,
380			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
381	do_lwsync_fixups(cur_cpu_spec->cpu_features,
382			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
383	do_final_fixups();
384
385	/*
386	 * Unflatten the device-tree passed by prom_init or kexec
387	 */
388	unflatten_device_tree();
389
390	/*
391	 * Fill the ppc64_caches & systemcfg structures with informations
392 	 * retrieved from the device-tree.
393	 */
394	initialize_cache_info();
395
396#ifdef CONFIG_PPC_RTAS
397	/*
398	 * Initialize RTAS if available
399	 */
400	rtas_initialize();
401#endif /* CONFIG_PPC_RTAS */
402
403	/*
404	 * Check if we have an initrd provided via the device-tree
405	 */
406	check_for_initrd();
407
408	/*
409	 * Do some platform specific early initializations, that includes
410	 * setting up the hash table pointers. It also sets up some interrupt-mapping
411	 * related options that will be used by finish_device_tree()
412	 */
413	if (ppc_md.init_early)
414		ppc_md.init_early();
415
416 	/*
417	 * We can discover serial ports now since the above did setup the
418	 * hash table management for us, thus ioremap works. We do that early
419	 * so that further code can be debugged
420	 */
421	find_legacy_serial_ports();
422
423	/*
424	 * Register early console
425	 */
426	register_early_udbg_console();
427
428	/*
429	 * Initialize xmon
430	 */
431	xmon_setup();
432
433	smp_setup_cpu_maps();
434	check_smt_enabled();
435
436#ifdef CONFIG_SMP
437	/* Release secondary cpus out of their spinloops at 0x60 now that
438	 * we can map physical -> logical CPU ids
439	 */
440	smp_release_cpus();
441#endif
442
443	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
444
445	printk("-----------------------------------------------------\n");
446	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
447	printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
448	if (ppc64_caches.dline_size != 0x80)
449		printk("ppc64_caches.dcache_line_size = 0x%x\n",
450		       ppc64_caches.dline_size);
451	if (ppc64_caches.iline_size != 0x80)
452		printk("ppc64_caches.icache_line_size = 0x%x\n",
453		       ppc64_caches.iline_size);
454#ifdef CONFIG_PPC_STD_MMU_64
455	if (htab_address)
456		printk("htab_address                  = 0x%p\n", htab_address);
457	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
458#endif /* CONFIG_PPC_STD_MMU_64 */
459	if (PHYSICAL_START > 0)
460		printk("physical_start                = 0x%llx\n",
461		       (unsigned long long)PHYSICAL_START);
462	printk("-----------------------------------------------------\n");
463
464	DBG(" <- setup_system()\n");
465}
466
467/* This returns the limit below which memory accesses to the linear
468 * mapping are guarnateed not to cause a TLB or SLB miss. This is
469 * used to allocate interrupt or emergency stacks for which our
470 * exception entry path doesn't deal with being interrupted.
471 */
472static u64 safe_stack_limit(void)
473{
474#ifdef CONFIG_PPC_BOOK3E
475	/* Freescale BookE bolts the entire linear mapping */
476	if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
477		return linear_map_top;
478	/* Other BookE, we assume the first GB is bolted */
479	return 1ul << 30;
480#else
481	/* BookS, the first segment is bolted */
482	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
483		return 1UL << SID_SHIFT_1T;
484	return 1UL << SID_SHIFT;
485#endif
486}
487
488static void __init irqstack_early_init(void)
489{
490	u64 limit = safe_stack_limit();
491	unsigned int i;
492
493	/*
494	 * Interrupt stacks must be in the first segment since we
495	 * cannot afford to take SLB misses on them.
496	 */
497	for_each_possible_cpu(i) {
498		softirq_ctx[i] = (struct thread_info *)
499			__va(memblock_alloc_base(THREAD_SIZE,
500					    THREAD_SIZE, limit));
501		hardirq_ctx[i] = (struct thread_info *)
502			__va(memblock_alloc_base(THREAD_SIZE,
503					    THREAD_SIZE, limit));
504	}
505}
506
507#ifdef CONFIG_PPC_BOOK3E
508static void __init exc_lvl_early_init(void)
509{
510	extern unsigned int interrupt_base_book3e;
511	extern unsigned int exc_debug_debug_book3e;
512
513	unsigned int i;
514
515	for_each_possible_cpu(i) {
516		critirq_ctx[i] = (struct thread_info *)
517			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
518		dbgirq_ctx[i] = (struct thread_info *)
519			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
520		mcheckirq_ctx[i] = (struct thread_info *)
521			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
522	}
523
524	if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
525		patch_branch(&interrupt_base_book3e + (0x040 / 4) + 1,
526			     (unsigned long)&exc_debug_debug_book3e, 0);
527}
528#else
529#define exc_lvl_early_init()
530#endif
531
532/*
533 * Stack space used when we detect a bad kernel stack pointer, and
534 * early in SMP boots before relocation is enabled.
535 */
536static void __init emergency_stack_init(void)
537{
538	u64 limit;
539	unsigned int i;
540
541	/*
542	 * Emergency stacks must be under 256MB, we cannot afford to take
543	 * SLB misses on them. The ABI also requires them to be 128-byte
544	 * aligned.
545	 *
546	 * Since we use these as temporary stacks during secondary CPU
547	 * bringup, we need to get at them in real mode. This means they
548	 * must also be within the RMO region.
549	 */
550	limit = min(safe_stack_limit(), ppc64_rma_size);
551
552	for_each_possible_cpu(i) {
553		unsigned long sp;
554		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
555		sp += THREAD_SIZE;
556		paca[i].emergency_sp = __va(sp);
557	}
558}
559
560/*
561 * Called into from start_kernel this initializes bootmem, which is used
562 * to manage page allocation until mem_init is called.
563 */
564void __init setup_arch(char **cmdline_p)
565{
566	ppc64_boot_msg(0x12, "Setup Arch");
567
568	*cmdline_p = cmd_line;
569
570	/*
571	 * Set cache line size based on type of cpu as a default.
572	 * Systems with OF can look in the properties on the cpu node(s)
573	 * for a possibly more accurate value.
574	 */
575	dcache_bsize = ppc64_caches.dline_size;
576	icache_bsize = ppc64_caches.iline_size;
577
578	/* reboot on panic */
579	panic_timeout = 180;
580
581	if (ppc_md.panic)
582		setup_panic();
583
584	init_mm.start_code = (unsigned long)_stext;
585	init_mm.end_code = (unsigned long) _etext;
586	init_mm.end_data = (unsigned long) _edata;
587	init_mm.brk = klimit;
588#ifdef CONFIG_PPC_64K_PAGES
589	init_mm.context.pte_frag = NULL;
590#endif
591	irqstack_early_init();
592	exc_lvl_early_init();
593	emergency_stack_init();
594
595#ifdef CONFIG_PPC_STD_MMU_64
596	stabs_alloc();
597#endif
598	/* set up the bootmem stuff with available memory */
599	do_init_bootmem();
600	sparse_init();
601
602#ifdef CONFIG_DUMMY_CONSOLE
603	conswitchp = &dummy_con;
604#endif
605
606	if (ppc_md.setup_arch)
607		ppc_md.setup_arch();
608
609	paging_init();
610
611	/* Initialize the MMU context management stuff */
612	mmu_context_init();
613
614	kvm_linear_init();
615
616	/* Interrupt code needs to be 64K-aligned */
617	if ((unsigned long)_stext & 0xffff)
618		panic("Kernelbase not 64K-aligned (0x%lx)!\n",
619		      (unsigned long)_stext);
620
621	ppc64_boot_msg(0x15, "Setup Done");
622}
623
624
625/* ToDo: do something useful if ppc_md is not yet setup. */
626#define PPC64_LINUX_FUNCTION 0x0f000000
627#define PPC64_IPL_MESSAGE 0xc0000000
628#define PPC64_TERM_MESSAGE 0xb0000000
629
630static void ppc64_do_msg(unsigned int src, const char *msg)
631{
632	if (ppc_md.progress) {
633		char buf[128];
634
635		sprintf(buf, "%08X\n", src);
636		ppc_md.progress(buf, 0);
637		snprintf(buf, 128, "%s", msg);
638		ppc_md.progress(buf, 0);
639	}
640}
641
642/* Print a boot progress message. */
643void ppc64_boot_msg(unsigned int src, const char *msg)
644{
645	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
646	printk("[boot]%04x %s\n", src, msg);
647}
648
649#ifdef CONFIG_SMP
650#define PCPU_DYN_SIZE		()
651
652static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
653{
654	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
655				    __pa(MAX_DMA_ADDRESS));
656}
657
658static void __init pcpu_fc_free(void *ptr, size_t size)
659{
660	free_bootmem(__pa(ptr), size);
661}
662
663static int pcpu_cpu_distance(unsigned int from, unsigned int to)
664{
665	if (cpu_to_node(from) == cpu_to_node(to))
666		return LOCAL_DISTANCE;
667	else
668		return REMOTE_DISTANCE;
669}
670
671unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
672EXPORT_SYMBOL(__per_cpu_offset);
673
674void __init setup_per_cpu_areas(void)
675{
676	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
677	size_t atom_size;
678	unsigned long delta;
679	unsigned int cpu;
680	int rc;
681
682	/*
683	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
684	 * to group units.  For larger mappings, use 1M atom which
685	 * should be large enough to contain a number of units.
686	 */
687	if (mmu_linear_psize == MMU_PAGE_4K)
688		atom_size = PAGE_SIZE;
689	else
690		atom_size = 1 << 20;
691
692	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
693				    pcpu_fc_alloc, pcpu_fc_free);
694	if (rc < 0)
695		panic("cannot initialize percpu area (err=%d)", rc);
696
697	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
698	for_each_possible_cpu(cpu) {
699                __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
700		paca[cpu].data_offset = __per_cpu_offset[cpu];
701	}
702}
703#endif
704
705
706#ifdef CONFIG_PPC_INDIRECT_IO
707struct ppc_pci_io ppc_pci_io;
708EXPORT_SYMBOL(ppc_pci_io);
709#endif /* CONFIG_PPC_INDIRECT_IO */
710
711