xref: /linux/arch/powerpc/kernel/setup_64.c (revision 463ce0e103f419f51b1769111e73fe8bb305d0ec)
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 <asm/io.h>
37 #include <asm/prom.h>
38 #include <asm/processor.h>
39 #include <asm/pgtable.h>
40 #include <asm/smp.h>
41 #include <asm/elf.h>
42 #include <asm/machdep.h>
43 #include <asm/paca.h>
44 #include <asm/time.h>
45 #include <asm/cputable.h>
46 #include <asm/sections.h>
47 #include <asm/btext.h>
48 #include <asm/nvram.h>
49 #include <asm/setup.h>
50 #include <asm/system.h>
51 #include <asm/rtas.h>
52 #include <asm/iommu.h>
53 #include <asm/serial.h>
54 #include <asm/cache.h>
55 #include <asm/page.h>
56 #include <asm/mmu.h>
57 #include <asm/lmb.h>
58 #include <asm/iseries/it_lp_naca.h>
59 #include <asm/firmware.h>
60 #include <asm/xmon.h>
61 #include <asm/udbg.h>
62 #include <asm/kexec.h>
63 
64 #include "setup.h"
65 
66 #ifdef DEBUG
67 #define DBG(fmt...) udbg_printf(fmt)
68 #else
69 #define DBG(fmt...)
70 #endif
71 
72 /*
73  * Here are some early debugging facilities. You can enable one
74  * but your kernel will not boot on anything else if you do so
75  */
76 
77 /* This one is for use on LPAR machines that support an HVC console
78  * on vterm 0
79  */
80 extern void udbg_init_debug_lpar(void);
81 /* This one is for use on Apple G5 machines
82  */
83 extern void udbg_init_pmac_realmode(void);
84 /* That's RTAS panel debug */
85 extern void call_rtas_display_status_delay(unsigned char c);
86 /* Here's maple real mode debug */
87 extern void udbg_init_maple_realmode(void);
88 
89 #define EARLY_DEBUG_INIT() do {} while(0)
90 
91 #if 0
92 #define EARLY_DEBUG_INIT() udbg_init_debug_lpar()
93 #define EARLY_DEBUG_INIT() udbg_init_maple_realmode()
94 #define EARLY_DEBUG_INIT() udbg_init_pmac_realmode()
95 #define EARLY_DEBUG_INIT()						\
96 	do { udbg_putc = call_rtas_display_status_delay; } while(0)
97 #endif
98 
99 int have_of = 1;
100 int boot_cpuid = 0;
101 int boot_cpuid_phys = 0;
102 dev_t boot_dev;
103 u64 ppc64_pft_size;
104 
105 /* Pick defaults since we might want to patch instructions
106  * before we've read this from the device tree.
107  */
108 struct ppc64_caches ppc64_caches = {
109 	.dline_size = 0x80,
110 	.log_dline_size = 7,
111 	.iline_size = 0x80,
112 	.log_iline_size = 7
113 };
114 EXPORT_SYMBOL_GPL(ppc64_caches);
115 
116 /*
117  * These are used in binfmt_elf.c to put aux entries on the stack
118  * for each elf executable being started.
119  */
120 int dcache_bsize;
121 int icache_bsize;
122 int ucache_bsize;
123 
124 /* The main machine-dep calls structure
125  */
126 struct machdep_calls ppc_md;
127 EXPORT_SYMBOL(ppc_md);
128 
129 #ifdef CONFIG_MAGIC_SYSRQ
130 unsigned long SYSRQ_KEY;
131 #endif /* CONFIG_MAGIC_SYSRQ */
132 
133 
134 static int ppc64_panic_event(struct notifier_block *, unsigned long, void *);
135 static struct notifier_block ppc64_panic_block = {
136 	.notifier_call = ppc64_panic_event,
137 	.priority = INT_MIN /* may not return; must be done last */
138 };
139 
140 #ifdef CONFIG_SMP
141 
142 static int smt_enabled_cmdline;
143 
144 /* Look for ibm,smt-enabled OF option */
145 static void check_smt_enabled(void)
146 {
147 	struct device_node *dn;
148 	char *smt_option;
149 
150 	/* Allow the command line to overrule the OF option */
151 	if (smt_enabled_cmdline)
152 		return;
153 
154 	dn = of_find_node_by_path("/options");
155 
156 	if (dn) {
157 		smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
158 
159                 if (smt_option) {
160 			if (!strcmp(smt_option, "on"))
161 				smt_enabled_at_boot = 1;
162 			else if (!strcmp(smt_option, "off"))
163 				smt_enabled_at_boot = 0;
164                 }
165         }
166 }
167 
168 /* Look for smt-enabled= cmdline option */
169 static int __init early_smt_enabled(char *p)
170 {
171 	smt_enabled_cmdline = 1;
172 
173 	if (!p)
174 		return 0;
175 
176 	if (!strcmp(p, "on") || !strcmp(p, "1"))
177 		smt_enabled_at_boot = 1;
178 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
179 		smt_enabled_at_boot = 0;
180 
181 	return 0;
182 }
183 early_param("smt-enabled", early_smt_enabled);
184 
185 #else
186 #define check_smt_enabled()
187 #endif /* CONFIG_SMP */
188 
189 extern struct machdep_calls pSeries_md;
190 extern struct machdep_calls pmac_md;
191 extern struct machdep_calls maple_md;
192 extern struct machdep_calls cell_md;
193 extern struct machdep_calls iseries_md;
194 
195 /* Ultimately, stuff them in an elf section like initcalls... */
196 static struct machdep_calls __initdata *machines[] = {
197 #ifdef CONFIG_PPC_PSERIES
198 	&pSeries_md,
199 #endif /* CONFIG_PPC_PSERIES */
200 #ifdef CONFIG_PPC_PMAC
201 	&pmac_md,
202 #endif /* CONFIG_PPC_PMAC */
203 #ifdef CONFIG_PPC_MAPLE
204 	&maple_md,
205 #endif /* CONFIG_PPC_MAPLE */
206 #ifdef CONFIG_PPC_CELL
207 	&cell_md,
208 #endif
209 #ifdef CONFIG_PPC_ISERIES
210 	&iseries_md,
211 #endif
212 	NULL
213 };
214 
215 /*
216  * Early initialization entry point. This is called by head.S
217  * with MMU translation disabled. We rely on the "feature" of
218  * the CPU that ignores the top 2 bits of the address in real
219  * mode so we can access kernel globals normally provided we
220  * only toy with things in the RMO region. From here, we do
221  * some early parsing of the device-tree to setup out LMB
222  * data structures, and allocate & initialize the hash table
223  * and segment tables so we can start running with translation
224  * enabled.
225  *
226  * It is this function which will call the probe() callback of
227  * the various platform types and copy the matching one to the
228  * global ppc_md structure. Your platform can eventually do
229  * some very early initializations from the probe() routine, but
230  * this is not recommended, be very careful as, for example, the
231  * device-tree is not accessible via normal means at this point.
232  */
233 
234 void __init early_setup(unsigned long dt_ptr)
235 {
236 	struct paca_struct *lpaca = get_paca();
237 	static struct machdep_calls **mach;
238 
239 	/*
240 	 * Enable early debugging if any specified (see top of
241 	 * this file)
242 	 */
243 	EARLY_DEBUG_INIT();
244 
245 	DBG(" -> early_setup()\n");
246 
247 	/*
248 	 * Do early initializations using the flattened device
249 	 * tree, like retreiving the physical memory map or
250 	 * calculating/retreiving the hash table size
251 	 */
252 	early_init_devtree(__va(dt_ptr));
253 
254 	/*
255 	 * Iterate all ppc_md structures until we find the proper
256 	 * one for the current machine type
257 	 */
258 	DBG("Probing machine type for platform %x...\n", _machine);
259 
260 	for (mach = machines; *mach; mach++) {
261 		if ((*mach)->probe(_machine))
262 			break;
263 	}
264 	/* What can we do if we didn't find ? */
265 	if (*mach == NULL) {
266 		DBG("No suitable machine found !\n");
267 		for (;;);
268 	}
269 	ppc_md = **mach;
270 
271 	DBG("Found, Initializing memory management...\n");
272 
273 	/*
274 	 * Initialize the MMU Hash table and create the linear mapping
275 	 * of memory. Has to be done before stab/slb initialization as
276 	 * this is currently where the page size encoding is obtained
277 	 */
278 	htab_initialize();
279 
280 	/*
281 	 * Initialize stab / SLB management except on iSeries
282 	 */
283 	if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
284 		if (cpu_has_feature(CPU_FTR_SLB))
285 			slb_initialize();
286 		else
287 			stab_initialize(lpaca->stab_real);
288 	}
289 
290 	DBG(" <- early_setup()\n");
291 }
292 
293 #ifdef CONFIG_SMP
294 void early_setup_secondary(void)
295 {
296 	struct paca_struct *lpaca = get_paca();
297 
298 	/* Mark enabled in PACA */
299 	lpaca->proc_enabled = 0;
300 
301 	/* Initialize hash table for that CPU */
302 	htab_initialize_secondary();
303 
304 	/* Initialize STAB/SLB. We use a virtual address as it works
305 	 * in real mode on pSeries and we want a virutal address on
306 	 * iSeries anyway
307 	 */
308 	if (cpu_has_feature(CPU_FTR_SLB))
309 		slb_initialize();
310 	else
311 		stab_initialize(lpaca->stab_addr);
312 }
313 
314 #endif /* CONFIG_SMP */
315 
316 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
317 void smp_release_cpus(void)
318 {
319 	extern unsigned long __secondary_hold_spinloop;
320 
321 	DBG(" -> smp_release_cpus()\n");
322 
323 	/* All secondary cpus are spinning on a common spinloop, release them
324 	 * all now so they can start to spin on their individual paca
325 	 * spinloops. For non SMP kernels, the secondary cpus never get out
326 	 * of the common spinloop.
327 	 * This is useless but harmless on iSeries, secondaries are already
328 	 * waiting on their paca spinloops. */
329 
330 	__secondary_hold_spinloop = 1;
331 	mb();
332 
333 	DBG(" <- smp_release_cpus()\n");
334 }
335 #else
336 #define smp_release_cpus()
337 #endif /* CONFIG_SMP || CONFIG_KEXEC */
338 
339 /*
340  * Initialize some remaining members of the ppc64_caches and systemcfg
341  * structures
342  * (at least until we get rid of them completely). This is mostly some
343  * cache informations about the CPU that will be used by cache flush
344  * routines and/or provided to userland
345  */
346 static void __init initialize_cache_info(void)
347 {
348 	struct device_node *np;
349 	unsigned long num_cpus = 0;
350 
351 	DBG(" -> initialize_cache_info()\n");
352 
353 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
354 		num_cpus += 1;
355 
356 		/* We're assuming *all* of the CPUs have the same
357 		 * d-cache and i-cache sizes... -Peter
358 		 */
359 
360 		if ( num_cpus == 1 ) {
361 			u32 *sizep, *lsizep;
362 			u32 size, lsize;
363 			const char *dc, *ic;
364 
365 			/* Then read cache informations */
366 			if (_machine == PLATFORM_POWERMAC) {
367 				dc = "d-cache-block-size";
368 				ic = "i-cache-block-size";
369 			} else {
370 				dc = "d-cache-line-size";
371 				ic = "i-cache-line-size";
372 			}
373 
374 			size = 0;
375 			lsize = cur_cpu_spec->dcache_bsize;
376 			sizep = (u32 *)get_property(np, "d-cache-size", NULL);
377 			if (sizep != NULL)
378 				size = *sizep;
379 			lsizep = (u32 *) get_property(np, dc, NULL);
380 			if (lsizep != NULL)
381 				lsize = *lsizep;
382 			if (sizep == 0 || lsizep == 0)
383 				DBG("Argh, can't find dcache properties ! "
384 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
385 
386 			ppc64_caches.dsize = size;
387 			ppc64_caches.dline_size = lsize;
388 			ppc64_caches.log_dline_size = __ilog2(lsize);
389 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
390 
391 			size = 0;
392 			lsize = cur_cpu_spec->icache_bsize;
393 			sizep = (u32 *)get_property(np, "i-cache-size", NULL);
394 			if (sizep != NULL)
395 				size = *sizep;
396 			lsizep = (u32 *)get_property(np, ic, NULL);
397 			if (lsizep != NULL)
398 				lsize = *lsizep;
399 			if (sizep == 0 || lsizep == 0)
400 				DBG("Argh, can't find icache properties ! "
401 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
402 
403 			ppc64_caches.isize = size;
404 			ppc64_caches.iline_size = lsize;
405 			ppc64_caches.log_iline_size = __ilog2(lsize);
406 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
407 		}
408 	}
409 
410 	DBG(" <- initialize_cache_info()\n");
411 }
412 
413 
414 /*
415  * Do some initial setup of the system.  The parameters are those which
416  * were passed in from the bootloader.
417  */
418 void __init setup_system(void)
419 {
420 	DBG(" -> setup_system()\n");
421 
422 	/*
423 	 * Unflatten the device-tree passed by prom_init or kexec
424 	 */
425 	unflatten_device_tree();
426 
427 #ifdef CONFIG_KEXEC
428 	kexec_setup();	/* requires unflattened device tree. */
429 #endif
430 
431 	/*
432 	 * Fill the ppc64_caches & systemcfg structures with informations
433 	 * retreived from the device-tree. Need to be called before
434 	 * finish_device_tree() since the later requires some of the
435 	 * informations filled up here to properly parse the interrupt
436 	 * tree.
437 	 * It also sets up the cache line sizes which allows to call
438 	 * routines like flush_icache_range (used by the hash init
439 	 * later on).
440 	 */
441 	initialize_cache_info();
442 
443 #ifdef CONFIG_PPC_RTAS
444 	/*
445 	 * Initialize RTAS if available
446 	 */
447 	rtas_initialize();
448 #endif /* CONFIG_PPC_RTAS */
449 
450 	/*
451 	 * Check if we have an initrd provided via the device-tree
452 	 */
453 	check_for_initrd();
454 
455 	/*
456 	 * Do some platform specific early initializations, that includes
457 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
458 	 * related options that will be used by finish_device_tree()
459 	 */
460 	ppc_md.init_early();
461 
462  	/*
463 	 * We can discover serial ports now since the above did setup the
464 	 * hash table management for us, thus ioremap works. We do that early
465 	 * so that further code can be debugged
466 	 */
467 #ifdef CONFIG_PPC_MULTIPLATFORM
468 	find_legacy_serial_ports();
469 #endif
470 
471 	/*
472 	 * "Finish" the device-tree, that is do the actual parsing of
473 	 * some of the properties like the interrupt map
474 	 */
475 	finish_device_tree();
476 
477 #ifdef CONFIG_BOOTX_TEXT
478 	init_boot_display();
479 #endif
480 
481 	/*
482 	 * Initialize xmon
483 	 */
484 #ifdef CONFIG_XMON_DEFAULT
485 	xmon_init(1);
486 #endif
487 	/*
488 	 * Register early console
489 	 */
490 	register_early_udbg_console();
491 
492 	/* Save unparsed command line copy for /proc/cmdline */
493 	strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
494 
495 	parse_early_param();
496 
497 	check_smt_enabled();
498 	smp_setup_cpu_maps();
499 
500 	/* Release secondary cpus out of their spinloops at 0x60 now that
501 	 * we can map physical -> logical CPU ids
502 	 */
503 	smp_release_cpus();
504 
505 	printk("Starting Linux PPC64 %s\n", system_utsname.version);
506 
507 	printk("-----------------------------------------------------\n");
508 	printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
509 	printk("ppc64_interrupt_controller    = 0x%ld\n",
510 	       ppc64_interrupt_controller);
511 	printk("platform                      = 0x%x\n", _machine);
512 	printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
513 	printk("ppc64_caches.dcache_line_size = 0x%x\n",
514 	       ppc64_caches.dline_size);
515 	printk("ppc64_caches.icache_line_size = 0x%x\n",
516 	       ppc64_caches.iline_size);
517 	printk("htab_address                  = 0x%p\n", htab_address);
518 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
519 	printk("-----------------------------------------------------\n");
520 
521 	mm_init_ppc64();
522 
523 	DBG(" <- setup_system()\n");
524 }
525 
526 static int ppc64_panic_event(struct notifier_block *this,
527                              unsigned long event, void *ptr)
528 {
529 	ppc_md.panic((char *)ptr);  /* May not return */
530 	return NOTIFY_DONE;
531 }
532 
533 #ifdef CONFIG_IRQSTACKS
534 static void __init irqstack_early_init(void)
535 {
536 	unsigned int i;
537 
538 	/*
539 	 * interrupt stacks must be under 256MB, we cannot afford to take
540 	 * SLB misses on them.
541 	 */
542 	for_each_cpu(i) {
543 		softirq_ctx[i] = (struct thread_info *)
544 			__va(lmb_alloc_base(THREAD_SIZE,
545 					    THREAD_SIZE, 0x10000000));
546 		hardirq_ctx[i] = (struct thread_info *)
547 			__va(lmb_alloc_base(THREAD_SIZE,
548 					    THREAD_SIZE, 0x10000000));
549 	}
550 }
551 #else
552 #define irqstack_early_init()
553 #endif
554 
555 /*
556  * Stack space used when we detect a bad kernel stack pointer, and
557  * early in SMP boots before relocation is enabled.
558  */
559 static void __init emergency_stack_init(void)
560 {
561 	unsigned long limit;
562 	unsigned int i;
563 
564 	/*
565 	 * Emergency stacks must be under 256MB, we cannot afford to take
566 	 * SLB misses on them. The ABI also requires them to be 128-byte
567 	 * aligned.
568 	 *
569 	 * Since we use these as temporary stacks during secondary CPU
570 	 * bringup, we need to get at them in real mode. This means they
571 	 * must also be within the RMO region.
572 	 */
573 	limit = min(0x10000000UL, lmb.rmo_size);
574 
575 	for_each_cpu(i)
576 		paca[i].emergency_sp =
577 		__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
578 }
579 
580 /*
581  * Called into from start_kernel, after lock_kernel has been called.
582  * Initializes bootmem, which is unsed to manage page allocation until
583  * mem_init is called.
584  */
585 void __init setup_arch(char **cmdline_p)
586 {
587 	extern void do_init_bootmem(void);
588 
589 	ppc64_boot_msg(0x12, "Setup Arch");
590 
591 	*cmdline_p = cmd_line;
592 
593 	/*
594 	 * Set cache line size based on type of cpu as a default.
595 	 * Systems with OF can look in the properties on the cpu node(s)
596 	 * for a possibly more accurate value.
597 	 */
598 	dcache_bsize = ppc64_caches.dline_size;
599 	icache_bsize = ppc64_caches.iline_size;
600 
601 	/* reboot on panic */
602 	panic_timeout = 180;
603 
604 	if (ppc_md.panic)
605 		notifier_chain_register(&panic_notifier_list, &ppc64_panic_block);
606 
607 	init_mm.start_code = PAGE_OFFSET;
608 	init_mm.end_code = (unsigned long) _etext;
609 	init_mm.end_data = (unsigned long) _edata;
610 	init_mm.brk = klimit;
611 
612 	irqstack_early_init();
613 	emergency_stack_init();
614 
615 	stabs_alloc();
616 
617 	/* set up the bootmem stuff with available memory */
618 	do_init_bootmem();
619 	sparse_init();
620 
621 #ifdef CONFIG_DUMMY_CONSOLE
622 	conswitchp = &dummy_con;
623 #endif
624 
625 	ppc_md.setup_arch();
626 
627 	/* Use the default idle loop if the platform hasn't provided one. */
628 	if (NULL == ppc_md.idle_loop) {
629 		ppc_md.idle_loop = default_idle;
630 		printk(KERN_INFO "Using default idle loop\n");
631 	}
632 
633 	paging_init();
634 	ppc64_boot_msg(0x15, "Setup Done");
635 }
636 
637 
638 /* ToDo: do something useful if ppc_md is not yet setup. */
639 #define PPC64_LINUX_FUNCTION 0x0f000000
640 #define PPC64_IPL_MESSAGE 0xc0000000
641 #define PPC64_TERM_MESSAGE 0xb0000000
642 
643 static void ppc64_do_msg(unsigned int src, const char *msg)
644 {
645 	if (ppc_md.progress) {
646 		char buf[128];
647 
648 		sprintf(buf, "%08X\n", src);
649 		ppc_md.progress(buf, 0);
650 		snprintf(buf, 128, "%s", msg);
651 		ppc_md.progress(buf, 0);
652 	}
653 }
654 
655 /* Print a boot progress message. */
656 void ppc64_boot_msg(unsigned int src, const char *msg)
657 {
658 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
659 	printk("[boot]%04x %s\n", src, msg);
660 }
661 
662 /* Print a termination message (print only -- does not stop the kernel) */
663 void ppc64_terminate_msg(unsigned int src, const char *msg)
664 {
665 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
666 	printk("[terminate]%04x %s\n", src, msg);
667 }
668 
669 int check_legacy_ioport(unsigned long base_port)
670 {
671 	if (ppc_md.check_legacy_ioport == NULL)
672 		return 0;
673 	return ppc_md.check_legacy_ioport(base_port);
674 }
675 EXPORT_SYMBOL(check_legacy_ioport);
676 
677 void cpu_die(void)
678 {
679 	if (ppc_md.cpu_die)
680 		ppc_md.cpu_die();
681 }
682