xref: /linux/arch/powerpc/kernel/setup_64.c (revision 4f1933620f57145212cdbb1ac6ce099eeeb21c5a)
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/config.h>
16 #include <linux/module.h>
17 #include <linux/string.h>
18 #include <linux/sched.h>
19 #include <linux/init.h>
20 #include <linux/kernel.h>
21 #include <linux/reboot.h>
22 #include <linux/delay.h>
23 #include <linux/initrd.h>
24 #include <linux/ide.h>
25 #include <linux/seq_file.h>
26 #include <linux/ioport.h>
27 #include <linux/console.h>
28 #include <linux/utsname.h>
29 #include <linux/tty.h>
30 #include <linux/root_dev.h>
31 #include <linux/notifier.h>
32 #include <linux/cpu.h>
33 #include <linux/unistd.h>
34 #include <linux/serial.h>
35 #include <linux/serial_8250.h>
36 #include <linux/bootmem.h>
37 #include <asm/io.h>
38 #include <asm/kdump.h>
39 #include <asm/prom.h>
40 #include <asm/processor.h>
41 #include <asm/pgtable.h>
42 #include <asm/smp.h>
43 #include <asm/elf.h>
44 #include <asm/machdep.h>
45 #include <asm/paca.h>
46 #include <asm/time.h>
47 #include <asm/cputable.h>
48 #include <asm/sections.h>
49 #include <asm/btext.h>
50 #include <asm/nvram.h>
51 #include <asm/setup.h>
52 #include <asm/system.h>
53 #include <asm/rtas.h>
54 #include <asm/iommu.h>
55 #include <asm/serial.h>
56 #include <asm/cache.h>
57 #include <asm/page.h>
58 #include <asm/mmu.h>
59 #include <asm/lmb.h>
60 #include <asm/iseries/it_lp_naca.h>
61 #include <asm/firmware.h>
62 #include <asm/xmon.h>
63 #include <asm/udbg.h>
64 #include <asm/kexec.h>
65 
66 #include "setup.h"
67 
68 #ifdef DEBUG
69 #define DBG(fmt...) udbg_printf(fmt)
70 #else
71 #define DBG(fmt...)
72 #endif
73 
74 int have_of = 1;
75 int boot_cpuid = 0;
76 int boot_cpuid_phys = 0;
77 dev_t boot_dev;
78 u64 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  */
83 struct ppc64_caches ppc64_caches = {
84 	.dline_size = 0x80,
85 	.log_dline_size = 7,
86 	.iline_size = 0x80,
87 	.log_iline_size = 7
88 };
89 EXPORT_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  */
95 int dcache_bsize;
96 int icache_bsize;
97 int ucache_bsize;
98 
99 /* The main machine-dep calls structure
100  */
101 struct machdep_calls ppc_md;
102 EXPORT_SYMBOL(ppc_md);
103 
104 #ifdef CONFIG_MAGIC_SYSRQ
105 unsigned long SYSRQ_KEY;
106 #endif /* CONFIG_MAGIC_SYSRQ */
107 
108 
109 static int ppc64_panic_event(struct notifier_block *, unsigned long, void *);
110 static struct notifier_block ppc64_panic_block = {
111 	.notifier_call = ppc64_panic_event,
112 	.priority = INT_MIN /* may not return; must be done last */
113 };
114 
115 #ifdef CONFIG_SMP
116 
117 static int smt_enabled_cmdline;
118 
119 /* Look for ibm,smt-enabled OF option */
120 static void check_smt_enabled(void)
121 {
122 	struct device_node *dn;
123 	char *smt_option;
124 
125 	/* Allow the command line to overrule the OF option */
126 	if (smt_enabled_cmdline)
127 		return;
128 
129 	dn = of_find_node_by_path("/options");
130 
131 	if (dn) {
132 		smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
133 
134                 if (smt_option) {
135 			if (!strcmp(smt_option, "on"))
136 				smt_enabled_at_boot = 1;
137 			else if (!strcmp(smt_option, "off"))
138 				smt_enabled_at_boot = 0;
139                 }
140         }
141 }
142 
143 /* Look for smt-enabled= cmdline option */
144 static int __init early_smt_enabled(char *p)
145 {
146 	smt_enabled_cmdline = 1;
147 
148 	if (!p)
149 		return 0;
150 
151 	if (!strcmp(p, "on") || !strcmp(p, "1"))
152 		smt_enabled_at_boot = 1;
153 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
154 		smt_enabled_at_boot = 0;
155 
156 	return 0;
157 }
158 early_param("smt-enabled", early_smt_enabled);
159 
160 #else
161 #define check_smt_enabled()
162 #endif /* CONFIG_SMP */
163 
164 extern struct machdep_calls pSeries_md;
165 extern struct machdep_calls pmac_md;
166 extern struct machdep_calls maple_md;
167 extern struct machdep_calls cell_md;
168 extern struct machdep_calls iseries_md;
169 
170 /* Ultimately, stuff them in an elf section like initcalls... */
171 static struct machdep_calls __initdata *machines[] = {
172 #ifdef CONFIG_PPC_PSERIES
173 	&pSeries_md,
174 #endif /* CONFIG_PPC_PSERIES */
175 #ifdef CONFIG_PPC_PMAC
176 	&pmac_md,
177 #endif /* CONFIG_PPC_PMAC */
178 #ifdef CONFIG_PPC_MAPLE
179 	&maple_md,
180 #endif /* CONFIG_PPC_MAPLE */
181 #ifdef CONFIG_PPC_CELL
182 	&cell_md,
183 #endif
184 #ifdef CONFIG_PPC_ISERIES
185 	&iseries_md,
186 #endif
187 	NULL
188 };
189 
190 /*
191  * Early initialization entry point. This is called by head.S
192  * with MMU translation disabled. We rely on the "feature" of
193  * the CPU that ignores the top 2 bits of the address in real
194  * mode so we can access kernel globals normally provided we
195  * only toy with things in the RMO region. From here, we do
196  * some early parsing of the device-tree to setup out LMB
197  * data structures, and allocate & initialize the hash table
198  * and segment tables so we can start running with translation
199  * enabled.
200  *
201  * It is this function which will call the probe() callback of
202  * the various platform types and copy the matching one to the
203  * global ppc_md structure. Your platform can eventually do
204  * some very early initializations from the probe() routine, but
205  * this is not recommended, be very careful as, for example, the
206  * device-tree is not accessible via normal means at this point.
207  */
208 
209 void __init early_setup(unsigned long dt_ptr)
210 {
211 	struct paca_struct *lpaca = get_paca();
212 	static struct machdep_calls **mach;
213 
214 	/* Enable early debugging if any specified (see udbg.h) */
215 	udbg_early_init();
216 
217 	DBG(" -> early_setup()\n");
218 
219 	/*
220 	 * Do early initializations using the flattened device
221 	 * tree, like retreiving the physical memory map or
222 	 * calculating/retreiving the hash table size
223 	 */
224 	early_init_devtree(__va(dt_ptr));
225 
226 	/*
227 	 * Iterate all ppc_md structures until we find the proper
228 	 * one for the current machine type
229 	 */
230 	DBG("Probing machine type for platform %x...\n", _machine);
231 
232 	for (mach = machines; *mach; mach++) {
233 		if ((*mach)->probe(_machine))
234 			break;
235 	}
236 	/* What can we do if we didn't find ? */
237 	if (*mach == NULL) {
238 		DBG("No suitable machine found !\n");
239 		for (;;);
240 	}
241 	ppc_md = **mach;
242 
243 #ifdef CONFIG_CRASH_DUMP
244 	kdump_setup();
245 #endif
246 
247 	DBG("Found, Initializing memory management...\n");
248 
249 	/*
250 	 * Initialize the MMU Hash table and create the linear mapping
251 	 * of memory. Has to be done before stab/slb initialization as
252 	 * this is currently where the page size encoding is obtained
253 	 */
254 	htab_initialize();
255 
256 	/*
257 	 * Initialize stab / SLB management except on iSeries
258 	 */
259 	if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
260 		if (cpu_has_feature(CPU_FTR_SLB))
261 			slb_initialize();
262 		else
263 			stab_initialize(lpaca->stab_real);
264 	}
265 
266 	DBG(" <- early_setup()\n");
267 }
268 
269 #ifdef CONFIG_SMP
270 void early_setup_secondary(void)
271 {
272 	struct paca_struct *lpaca = get_paca();
273 
274 	/* Mark enabled in PACA */
275 	lpaca->proc_enabled = 0;
276 
277 	/* Initialize hash table for that CPU */
278 	htab_initialize_secondary();
279 
280 	/* Initialize STAB/SLB. We use a virtual address as it works
281 	 * in real mode on pSeries and we want a virutal address on
282 	 * iSeries anyway
283 	 */
284 	if (cpu_has_feature(CPU_FTR_SLB))
285 		slb_initialize();
286 	else
287 		stab_initialize(lpaca->stab_addr);
288 }
289 
290 #endif /* CONFIG_SMP */
291 
292 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
293 void smp_release_cpus(void)
294 {
295 	extern unsigned long __secondary_hold_spinloop;
296 	unsigned long *ptr;
297 
298 	DBG(" -> smp_release_cpus()\n");
299 
300 	/* All secondary cpus are spinning on a common spinloop, release them
301 	 * all now so they can start to spin on their individual paca
302 	 * spinloops. For non SMP kernels, the secondary cpus never get out
303 	 * of the common spinloop.
304 	 * This is useless but harmless on iSeries, secondaries are already
305 	 * waiting on their paca spinloops. */
306 
307 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
308 			- PHYSICAL_START);
309 	*ptr = 1;
310 	mb();
311 
312 	DBG(" <- smp_release_cpus()\n");
313 }
314 #else
315 #define smp_release_cpus()
316 #endif /* CONFIG_SMP || CONFIG_KEXEC */
317 
318 /*
319  * Initialize some remaining members of the ppc64_caches and systemcfg
320  * structures
321  * (at least until we get rid of them completely). This is mostly some
322  * cache informations about the CPU that will be used by cache flush
323  * routines and/or provided to userland
324  */
325 static void __init initialize_cache_info(void)
326 {
327 	struct device_node *np;
328 	unsigned long num_cpus = 0;
329 
330 	DBG(" -> initialize_cache_info()\n");
331 
332 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
333 		num_cpus += 1;
334 
335 		/* We're assuming *all* of the CPUs have the same
336 		 * d-cache and i-cache sizes... -Peter
337 		 */
338 
339 		if ( num_cpus == 1 ) {
340 			u32 *sizep, *lsizep;
341 			u32 size, lsize;
342 			const char *dc, *ic;
343 
344 			/* Then read cache informations */
345 			if (_machine == PLATFORM_POWERMAC) {
346 				dc = "d-cache-block-size";
347 				ic = "i-cache-block-size";
348 			} else {
349 				dc = "d-cache-line-size";
350 				ic = "i-cache-line-size";
351 			}
352 
353 			size = 0;
354 			lsize = cur_cpu_spec->dcache_bsize;
355 			sizep = (u32 *)get_property(np, "d-cache-size", NULL);
356 			if (sizep != NULL)
357 				size = *sizep;
358 			lsizep = (u32 *) get_property(np, dc, NULL);
359 			if (lsizep != NULL)
360 				lsize = *lsizep;
361 			if (sizep == 0 || lsizep == 0)
362 				DBG("Argh, can't find dcache properties ! "
363 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
364 
365 			ppc64_caches.dsize = size;
366 			ppc64_caches.dline_size = lsize;
367 			ppc64_caches.log_dline_size = __ilog2(lsize);
368 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
369 
370 			size = 0;
371 			lsize = cur_cpu_spec->icache_bsize;
372 			sizep = (u32 *)get_property(np, "i-cache-size", NULL);
373 			if (sizep != NULL)
374 				size = *sizep;
375 			lsizep = (u32 *)get_property(np, ic, NULL);
376 			if (lsizep != NULL)
377 				lsize = *lsizep;
378 			if (sizep == 0 || lsizep == 0)
379 				DBG("Argh, can't find icache properties ! "
380 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
381 
382 			ppc64_caches.isize = size;
383 			ppc64_caches.iline_size = lsize;
384 			ppc64_caches.log_iline_size = __ilog2(lsize);
385 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
386 		}
387 	}
388 
389 	DBG(" <- initialize_cache_info()\n");
390 }
391 
392 
393 /*
394  * Do some initial setup of the system.  The parameters are those which
395  * were passed in from the bootloader.
396  */
397 void __init setup_system(void)
398 {
399 	DBG(" -> setup_system()\n");
400 
401 #ifdef CONFIG_KEXEC
402 	kdump_move_device_tree();
403 #endif
404 	/*
405 	 * Unflatten the device-tree passed by prom_init or kexec
406 	 */
407 	unflatten_device_tree();
408 
409 #ifdef CONFIG_KEXEC
410 	kexec_setup();	/* requires unflattened device tree. */
411 #endif
412 
413 	/*
414 	 * Fill the ppc64_caches & systemcfg structures with informations
415 	 * retrieved from the device-tree. Need to be called before
416 	 * finish_device_tree() since the later requires some of the
417 	 * informations filled up here to properly parse the interrupt
418 	 * tree.
419 	 * It also sets up the cache line sizes which allows to call
420 	 * routines like flush_icache_range (used by the hash init
421 	 * later on).
422 	 */
423 	initialize_cache_info();
424 
425 #ifdef CONFIG_PPC_RTAS
426 	/*
427 	 * Initialize RTAS if available
428 	 */
429 	rtas_initialize();
430 #endif /* CONFIG_PPC_RTAS */
431 
432 	/*
433 	 * Check if we have an initrd provided via the device-tree
434 	 */
435 	check_for_initrd();
436 
437 	/*
438 	 * Do some platform specific early initializations, that includes
439 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
440 	 * related options that will be used by finish_device_tree()
441 	 */
442 	ppc_md.init_early();
443 
444  	/*
445 	 * We can discover serial ports now since the above did setup the
446 	 * hash table management for us, thus ioremap works. We do that early
447 	 * so that further code can be debugged
448 	 */
449 	find_legacy_serial_ports();
450 
451 	/*
452 	 * "Finish" the device-tree, that is do the actual parsing of
453 	 * some of the properties like the interrupt map
454 	 */
455 	finish_device_tree();
456 
457 	/*
458 	 * Initialize xmon
459 	 */
460 #ifdef CONFIG_XMON_DEFAULT
461 	xmon_init(1);
462 #endif
463 	/*
464 	 * Register early console
465 	 */
466 	register_early_udbg_console();
467 
468 	/* Save unparsed command line copy for /proc/cmdline */
469 	strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
470 
471 	parse_early_param();
472 
473 	check_smt_enabled();
474 	smp_setup_cpu_maps();
475 
476 	/* Release secondary cpus out of their spinloops at 0x60 now that
477 	 * we can map physical -> logical CPU ids
478 	 */
479 	smp_release_cpus();
480 
481 	printk("Starting Linux PPC64 %s\n", system_utsname.version);
482 
483 	printk("-----------------------------------------------------\n");
484 	printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
485 	printk("ppc64_interrupt_controller    = 0x%ld\n",
486 	       ppc64_interrupt_controller);
487 	printk("platform                      = 0x%x\n", _machine);
488 	printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
489 	printk("ppc64_caches.dcache_line_size = 0x%x\n",
490 	       ppc64_caches.dline_size);
491 	printk("ppc64_caches.icache_line_size = 0x%x\n",
492 	       ppc64_caches.iline_size);
493 	printk("htab_address                  = 0x%p\n", htab_address);
494 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
495 #if PHYSICAL_START > 0
496 	printk("physical_start                = 0x%x\n", PHYSICAL_START);
497 #endif
498 	printk("-----------------------------------------------------\n");
499 
500 	mm_init_ppc64();
501 
502 	DBG(" <- setup_system()\n");
503 }
504 
505 static int ppc64_panic_event(struct notifier_block *this,
506                              unsigned long event, void *ptr)
507 {
508 	ppc_md.panic((char *)ptr);  /* May not return */
509 	return NOTIFY_DONE;
510 }
511 
512 #ifdef CONFIG_IRQSTACKS
513 static void __init irqstack_early_init(void)
514 {
515 	unsigned int i;
516 
517 	/*
518 	 * interrupt stacks must be under 256MB, we cannot afford to take
519 	 * SLB misses on them.
520 	 */
521 	for_each_cpu(i) {
522 		softirq_ctx[i] = (struct thread_info *)
523 			__va(lmb_alloc_base(THREAD_SIZE,
524 					    THREAD_SIZE, 0x10000000));
525 		hardirq_ctx[i] = (struct thread_info *)
526 			__va(lmb_alloc_base(THREAD_SIZE,
527 					    THREAD_SIZE, 0x10000000));
528 	}
529 }
530 #else
531 #define irqstack_early_init()
532 #endif
533 
534 /*
535  * Stack space used when we detect a bad kernel stack pointer, and
536  * early in SMP boots before relocation is enabled.
537  */
538 static void __init emergency_stack_init(void)
539 {
540 	unsigned long limit;
541 	unsigned int i;
542 
543 	/*
544 	 * Emergency stacks must be under 256MB, we cannot afford to take
545 	 * SLB misses on them. The ABI also requires them to be 128-byte
546 	 * aligned.
547 	 *
548 	 * Since we use these as temporary stacks during secondary CPU
549 	 * bringup, we need to get at them in real mode. This means they
550 	 * must also be within the RMO region.
551 	 */
552 	limit = min(0x10000000UL, lmb.rmo_size);
553 
554 	for_each_cpu(i)
555 		paca[i].emergency_sp =
556 		__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
557 }
558 
559 /*
560  * Called into from start_kernel, after lock_kernel has been called.
561  * Initializes bootmem, which is unsed to manage page allocation until
562  * mem_init is called.
563  */
564 void __init setup_arch(char **cmdline_p)
565 {
566 	extern void do_init_bootmem(void);
567 
568 	ppc64_boot_msg(0x12, "Setup Arch");
569 
570 	*cmdline_p = cmd_line;
571 
572 	/*
573 	 * Set cache line size based on type of cpu as a default.
574 	 * Systems with OF can look in the properties on the cpu node(s)
575 	 * for a possibly more accurate value.
576 	 */
577 	dcache_bsize = ppc64_caches.dline_size;
578 	icache_bsize = ppc64_caches.iline_size;
579 
580 	/* reboot on panic */
581 	panic_timeout = 180;
582 
583 	if (ppc_md.panic)
584 		notifier_chain_register(&panic_notifier_list, &ppc64_panic_block);
585 
586 	init_mm.start_code = PAGE_OFFSET;
587 	init_mm.end_code = (unsigned long) _etext;
588 	init_mm.end_data = (unsigned long) _edata;
589 	init_mm.brk = klimit;
590 
591 	irqstack_early_init();
592 	emergency_stack_init();
593 
594 	stabs_alloc();
595 
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 	ppc_md.setup_arch();
605 
606 	/* Use the default idle loop if the platform hasn't provided one. */
607 	if (NULL == ppc_md.idle_loop) {
608 		ppc_md.idle_loop = default_idle;
609 		printk(KERN_INFO "Using default idle loop\n");
610 	}
611 
612 	paging_init();
613 	ppc64_boot_msg(0x15, "Setup Done");
614 }
615 
616 
617 /* ToDo: do something useful if ppc_md is not yet setup. */
618 #define PPC64_LINUX_FUNCTION 0x0f000000
619 #define PPC64_IPL_MESSAGE 0xc0000000
620 #define PPC64_TERM_MESSAGE 0xb0000000
621 
622 static void ppc64_do_msg(unsigned int src, const char *msg)
623 {
624 	if (ppc_md.progress) {
625 		char buf[128];
626 
627 		sprintf(buf, "%08X\n", src);
628 		ppc_md.progress(buf, 0);
629 		snprintf(buf, 128, "%s", msg);
630 		ppc_md.progress(buf, 0);
631 	}
632 }
633 
634 /* Print a boot progress message. */
635 void ppc64_boot_msg(unsigned int src, const char *msg)
636 {
637 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
638 	printk("[boot]%04x %s\n", src, msg);
639 }
640 
641 /* Print a termination message (print only -- does not stop the kernel) */
642 void ppc64_terminate_msg(unsigned int src, const char *msg)
643 {
644 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
645 	printk("[terminate]%04x %s\n", src, msg);
646 }
647 
648 int check_legacy_ioport(unsigned long base_port)
649 {
650 	if (ppc_md.check_legacy_ioport == NULL)
651 		return 0;
652 	return ppc_md.check_legacy_ioport(base_port);
653 }
654 EXPORT_SYMBOL(check_legacy_ioport);
655 
656 void cpu_die(void)
657 {
658 	if (ppc_md.cpu_die)
659 		ppc_md.cpu_die();
660 }
661 
662 #ifdef CONFIG_SMP
663 void __init setup_per_cpu_areas(void)
664 {
665 	int i;
666 	unsigned long size;
667 	char *ptr;
668 
669 	/* Copy section for each CPU (we discard the original) */
670 	size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
671 #ifdef CONFIG_MODULES
672 	if (size < PERCPU_ENOUGH_ROOM)
673 		size = PERCPU_ENOUGH_ROOM;
674 #endif
675 
676 	for_each_cpu(i) {
677 		ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
678 		if (!ptr)
679 			panic("Cannot allocate cpu data for CPU %d\n", i);
680 
681 		paca[i].data_offset = ptr - __per_cpu_start;
682 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
683 	}
684 }
685 #endif
686