setup_64.c revision 33642d31d19c967b9739253912cdd48885509805 
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/module.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/lmb.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
65#include "setup.h"
66
67#ifdef DEBUG
68#define DBG(fmt...) udbg_printf(fmt)
69#else
70#define DBG(fmt...)
71#endif
72
73int boot_cpuid = 0;
74u64 ppc64_pft_size;
75
76/* Pick defaults since we might want to patch instructions
77 * before we've read this from the device tree.
78 */
79struct ppc64_caches ppc64_caches = {
80	.dline_size = 0x40,
81	.log_dline_size = 6,
82	.iline_size = 0x40,
83	.log_iline_size = 6
84};
85EXPORT_SYMBOL_GPL(ppc64_caches);
86
87/*
88 * These are used in binfmt_elf.c to put aux entries on the stack
89 * for each elf executable being started.
90 */
91int dcache_bsize;
92int icache_bsize;
93int ucache_bsize;
94
95#ifdef CONFIG_SMP
96
97static int smt_enabled_cmdline;
98
99/* Look for ibm,smt-enabled OF option */
100static void check_smt_enabled(void)
101{
102	struct device_node *dn;
103	const char *smt_option;
104
105	/* Allow the command line to overrule the OF option */
106	if (smt_enabled_cmdline)
107		return;
108
109	dn = of_find_node_by_path("/options");
110
111	if (dn) {
112		smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
113
114                if (smt_option) {
115			if (!strcmp(smt_option, "on"))
116				smt_enabled_at_boot = 1;
117			else if (!strcmp(smt_option, "off"))
118				smt_enabled_at_boot = 0;
119                }
120        }
121}
122
123/* Look for smt-enabled= cmdline option */
124static int __init early_smt_enabled(char *p)
125{
126	smt_enabled_cmdline = 1;
127
128	if (!p)
129		return 0;
130
131	if (!strcmp(p, "on") || !strcmp(p, "1"))
132		smt_enabled_at_boot = 1;
133	else if (!strcmp(p, "off") || !strcmp(p, "0"))
134		smt_enabled_at_boot = 0;
135
136	return 0;
137}
138early_param("smt-enabled", early_smt_enabled);
139
140#else
141#define check_smt_enabled()
142#endif /* CONFIG_SMP */
143
144/* Put the paca pointer into r13 and SPRG3 */
145void __init setup_paca(int cpu)
146{
147	local_paca = &paca[cpu];
148	mtspr(SPRN_SPRG3, local_paca);
149}
150
151/*
152 * Early initialization entry point. This is called by head.S
153 * with MMU translation disabled. We rely on the "feature" of
154 * the CPU that ignores the top 2 bits of the address in real
155 * mode so we can access kernel globals normally provided we
156 * only toy with things in the RMO region. From here, we do
157 * some early parsing of the device-tree to setup out LMB
158 * data structures, and allocate & initialize the hash table
159 * and segment tables so we can start running with translation
160 * enabled.
161 *
162 * It is this function which will call the probe() callback of
163 * the various platform types and copy the matching one to the
164 * global ppc_md structure. Your platform can eventually do
165 * some very early initializations from the probe() routine, but
166 * this is not recommended, be very careful as, for example, the
167 * device-tree is not accessible via normal means at this point.
168 */
169
170void __init early_setup(unsigned long dt_ptr)
171{
172	/* -------- printk is _NOT_ safe to use here ! ------- */
173
174	/* Fill in any unititialised pacas */
175	initialise_pacas();
176
177	/* Identify CPU type */
178	identify_cpu(0, mfspr(SPRN_PVR));
179
180	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
181	setup_paca(0);
182
183	/* Initialize lockdep early or else spinlocks will blow */
184	lockdep_init();
185
186	/* -------- printk is now safe to use ------- */
187
188	/* Enable early debugging if any specified (see udbg.h) */
189	udbg_early_init();
190
191 	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
192
193	/*
194	 * Do early initialization using the flattened device
195	 * tree, such as retrieving the physical memory map or
196	 * calculating/retrieving the hash table size.
197	 */
198	early_init_devtree(__va(dt_ptr));
199
200	/* Now we know the logical id of our boot cpu, setup the paca. */
201	setup_paca(boot_cpuid);
202
203	/* Fix up paca fields required for the boot cpu */
204	get_paca()->cpu_start = 1;
205	get_paca()->stab_real = __pa((u64)&initial_stab);
206	get_paca()->stab_addr = (u64)&initial_stab;
207
208	/* Probe the machine type */
209	probe_machine();
210
211	setup_kdump_trampoline();
212
213	DBG("Found, Initializing memory management...\n");
214
215	/*
216	 * Initialize the MMU Hash table and create the linear mapping
217	 * of memory. Has to be done before stab/slb initialization as
218	 * this is currently where the page size encoding is obtained
219	 */
220	htab_initialize();
221
222	/*
223	 * Initialize stab / SLB management except on iSeries
224	 */
225	if (cpu_has_feature(CPU_FTR_SLB))
226		slb_initialize();
227	else if (!firmware_has_feature(FW_FEATURE_ISERIES))
228		stab_initialize(get_paca()->stab_real);
229
230	DBG(" <- early_setup()\n");
231}
232
233#ifdef CONFIG_SMP
234void early_setup_secondary(void)
235{
236	struct paca_struct *lpaca = get_paca();
237
238	/* Mark interrupts enabled in PACA */
239	lpaca->soft_enabled = 0;
240
241	/* Initialize hash table for that CPU */
242	htab_initialize_secondary();
243
244	/* Initialize STAB/SLB. We use a virtual address as it works
245	 * in real mode on pSeries and we want a virutal address on
246	 * iSeries anyway
247	 */
248	if (cpu_has_feature(CPU_FTR_SLB))
249		slb_initialize();
250	else
251		stab_initialize(lpaca->stab_addr);
252}
253
254#endif /* CONFIG_SMP */
255
256#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
257extern unsigned long __secondary_hold_spinloop;
258extern void generic_secondary_smp_init(void);
259
260void smp_release_cpus(void)
261{
262	unsigned long *ptr;
263
264	DBG(" -> smp_release_cpus()\n");
265
266	/* All secondary cpus are spinning on a common spinloop, release them
267	 * all now so they can start to spin on their individual paca
268	 * spinloops. For non SMP kernels, the secondary cpus never get out
269	 * of the common spinloop.
270	 */
271
272	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
273			- PHYSICAL_START);
274	*ptr = __pa(generic_secondary_smp_init);
275	mb();
276
277	DBG(" <- smp_release_cpus()\n");
278}
279#endif /* CONFIG_SMP || CONFIG_KEXEC */
280
281/*
282 * Initialize some remaining members of the ppc64_caches and systemcfg
283 * structures
284 * (at least until we get rid of them completely). This is mostly some
285 * cache informations about the CPU that will be used by cache flush
286 * routines and/or provided to userland
287 */
288static void __init initialize_cache_info(void)
289{
290	struct device_node *np;
291	unsigned long num_cpus = 0;
292
293	DBG(" -> initialize_cache_info()\n");
294
295	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
296		num_cpus += 1;
297
298		/* We're assuming *all* of the CPUs have the same
299		 * d-cache and i-cache sizes... -Peter
300		 */
301
302		if ( num_cpus == 1 ) {
303			const u32 *sizep, *lsizep;
304			u32 size, lsize;
305
306			size = 0;
307			lsize = cur_cpu_spec->dcache_bsize;
308			sizep = of_get_property(np, "d-cache-size", NULL);
309			if (sizep != NULL)
310				size = *sizep;
311			lsizep = of_get_property(np, "d-cache-block-size", NULL);
312			/* fallback if block size missing */
313			if (lsizep == NULL)
314				lsizep = of_get_property(np, "d-cache-line-size", NULL);
315			if (lsizep != NULL)
316				lsize = *lsizep;
317			if (sizep == 0 || lsizep == 0)
318				DBG("Argh, can't find dcache properties ! "
319				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
320
321			ppc64_caches.dsize = size;
322			ppc64_caches.dline_size = lsize;
323			ppc64_caches.log_dline_size = __ilog2(lsize);
324			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
325
326			size = 0;
327			lsize = cur_cpu_spec->icache_bsize;
328			sizep = of_get_property(np, "i-cache-size", NULL);
329			if (sizep != NULL)
330				size = *sizep;
331			lsizep = of_get_property(np, "i-cache-block-size", NULL);
332			if (lsizep == NULL)
333				lsizep = of_get_property(np, "i-cache-line-size", NULL);
334			if (lsizep != NULL)
335				lsize = *lsizep;
336			if (sizep == 0 || lsizep == 0)
337				DBG("Argh, can't find icache properties ! "
338				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
339
340			ppc64_caches.isize = size;
341			ppc64_caches.iline_size = lsize;
342			ppc64_caches.log_iline_size = __ilog2(lsize);
343			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
344		}
345	}
346
347	DBG(" <- initialize_cache_info()\n");
348}
349
350
351/*
352 * Do some initial setup of the system.  The parameters are those which
353 * were passed in from the bootloader.
354 */
355void __init setup_system(void)
356{
357	DBG(" -> setup_system()\n");
358
359	/* Apply the CPUs-specific and firmware specific fixups to kernel
360	 * text (nop out sections not relevant to this CPU or this firmware)
361	 */
362	do_feature_fixups(cur_cpu_spec->cpu_features,
363			  &__start___ftr_fixup, &__stop___ftr_fixup);
364	do_feature_fixups(cur_cpu_spec->mmu_features,
365			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
366	do_feature_fixups(powerpc_firmware_features,
367			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
368	do_lwsync_fixups(cur_cpu_spec->cpu_features,
369			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
370
371	/*
372	 * Unflatten the device-tree passed by prom_init or kexec
373	 */
374	unflatten_device_tree();
375
376	/*
377	 * Fill the ppc64_caches & systemcfg structures with informations
378 	 * retrieved from the device-tree.
379	 */
380	initialize_cache_info();
381
382	/*
383	 * Initialize irq remapping subsystem
384	 */
385	irq_early_init();
386
387#ifdef CONFIG_PPC_RTAS
388	/*
389	 * Initialize RTAS if available
390	 */
391	rtas_initialize();
392#endif /* CONFIG_PPC_RTAS */
393
394	/*
395	 * Check if we have an initrd provided via the device-tree
396	 */
397	check_for_initrd();
398
399	/*
400	 * Do some platform specific early initializations, that includes
401	 * setting up the hash table pointers. It also sets up some interrupt-mapping
402	 * related options that will be used by finish_device_tree()
403	 */
404	if (ppc_md.init_early)
405		ppc_md.init_early();
406
407 	/*
408	 * We can discover serial ports now since the above did setup the
409	 * hash table management for us, thus ioremap works. We do that early
410	 * so that further code can be debugged
411	 */
412	find_legacy_serial_ports();
413
414	/*
415	 * Register early console
416	 */
417	register_early_udbg_console();
418
419	/*
420	 * Initialize xmon
421	 */
422	xmon_setup();
423
424	check_smt_enabled();
425	smp_setup_cpu_maps();
426
427#ifdef CONFIG_SMP
428	/* Release secondary cpus out of their spinloops at 0x60 now that
429	 * we can map physical -> logical CPU ids
430	 */
431	smp_release_cpus();
432#endif
433
434	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
435
436	printk("-----------------------------------------------------\n");
437	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
438	printk("physicalMemorySize            = 0x%llx\n", lmb_phys_mem_size());
439	if (ppc64_caches.dline_size != 0x80)
440		printk("ppc64_caches.dcache_line_size = 0x%x\n",
441		       ppc64_caches.dline_size);
442	if (ppc64_caches.iline_size != 0x80)
443		printk("ppc64_caches.icache_line_size = 0x%x\n",
444		       ppc64_caches.iline_size);
445	if (htab_address)
446		printk("htab_address                  = 0x%p\n", htab_address);
447	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
448	if (PHYSICAL_START > 0)
449		printk("physical_start                = 0x%lx\n",
450		       PHYSICAL_START);
451	printk("-----------------------------------------------------\n");
452
453	DBG(" <- setup_system()\n");
454}
455
456#ifdef CONFIG_IRQSTACKS
457static void __init irqstack_early_init(void)
458{
459	unsigned int i;
460
461	/*
462	 * interrupt stacks must be under 256MB, we cannot afford to take
463	 * SLB misses on them.
464	 */
465	for_each_possible_cpu(i) {
466		softirq_ctx[i] = (struct thread_info *)
467			__va(lmb_alloc_base(THREAD_SIZE,
468					    THREAD_SIZE, 0x10000000));
469		hardirq_ctx[i] = (struct thread_info *)
470			__va(lmb_alloc_base(THREAD_SIZE,
471					    THREAD_SIZE, 0x10000000));
472	}
473}
474#else
475#define irqstack_early_init()
476#endif
477
478/*
479 * Stack space used when we detect a bad kernel stack pointer, and
480 * early in SMP boots before relocation is enabled.
481 */
482static void __init emergency_stack_init(void)
483{
484	unsigned long limit;
485	unsigned int i;
486
487	/*
488	 * Emergency stacks must be under 256MB, we cannot afford to take
489	 * SLB misses on them. The ABI also requires them to be 128-byte
490	 * aligned.
491	 *
492	 * Since we use these as temporary stacks during secondary CPU
493	 * bringup, we need to get at them in real mode. This means they
494	 * must also be within the RMO region.
495	 */
496	limit = min(0x10000000ULL, lmb.rmo_size);
497
498	for_each_possible_cpu(i) {
499		unsigned long sp;
500		sp  = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
501		sp += THREAD_SIZE;
502		paca[i].emergency_sp = __va(sp);
503	}
504}
505
506/*
507 * Called into from start_kernel, after lock_kernel has been called.
508 * Initializes bootmem, which is unsed to manage page allocation until
509 * mem_init is called.
510 */
511void __init setup_arch(char **cmdline_p)
512{
513	ppc64_boot_msg(0x12, "Setup Arch");
514
515	*cmdline_p = cmd_line;
516
517	/*
518	 * Set cache line size based on type of cpu as a default.
519	 * Systems with OF can look in the properties on the cpu node(s)
520	 * for a possibly more accurate value.
521	 */
522	dcache_bsize = ppc64_caches.dline_size;
523	icache_bsize = ppc64_caches.iline_size;
524
525	/* reboot on panic */
526	panic_timeout = 180;
527
528	if (ppc_md.panic)
529		setup_panic();
530
531	init_mm.start_code = (unsigned long)_stext;
532	init_mm.end_code = (unsigned long) _etext;
533	init_mm.end_data = (unsigned long) _edata;
534	init_mm.brk = klimit;
535
536	irqstack_early_init();
537	emergency_stack_init();
538
539	stabs_alloc();
540
541	/* set up the bootmem stuff with available memory */
542	do_init_bootmem();
543	sparse_init();
544
545#ifdef CONFIG_DUMMY_CONSOLE
546	conswitchp = &dummy_con;
547#endif
548
549	if (ppc_md.setup_arch)
550		ppc_md.setup_arch();
551
552	paging_init();
553	ppc64_boot_msg(0x15, "Setup Done");
554}
555
556
557/* ToDo: do something useful if ppc_md is not yet setup. */
558#define PPC64_LINUX_FUNCTION 0x0f000000
559#define PPC64_IPL_MESSAGE 0xc0000000
560#define PPC64_TERM_MESSAGE 0xb0000000
561
562static void ppc64_do_msg(unsigned int src, const char *msg)
563{
564	if (ppc_md.progress) {
565		char buf[128];
566
567		sprintf(buf, "%08X\n", src);
568		ppc_md.progress(buf, 0);
569		snprintf(buf, 128, "%s", msg);
570		ppc_md.progress(buf, 0);
571	}
572}
573
574/* Print a boot progress message. */
575void ppc64_boot_msg(unsigned int src, const char *msg)
576{
577	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
578	printk("[boot]%04x %s\n", src, msg);
579}
580
581void cpu_die(void)
582{
583	if (ppc_md.cpu_die)
584		ppc_md.cpu_die();
585}
586
587#ifdef CONFIG_SMP
588void __init setup_per_cpu_areas(void)
589{
590	int i;
591	unsigned long size;
592	char *ptr;
593
594	/* Copy section for each CPU (we discard the original) */
595	size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
596#ifdef CONFIG_MODULES
597	if (size < PERCPU_ENOUGH_ROOM)
598		size = PERCPU_ENOUGH_ROOM;
599#endif
600
601	for_each_possible_cpu(i) {
602		ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
603
604		paca[i].data_offset = ptr - __per_cpu_start;
605		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
606	}
607}
608#endif
609
610
611#ifdef CONFIG_PPC_INDIRECT_IO
612struct ppc_pci_io ppc_pci_io;
613EXPORT_SYMBOL(ppc_pci_io);
614#endif /* CONFIG_PPC_INDIRECT_IO */
615
616