xref: /openbmc/linux/arch/powerpc/kernel/setup_64.c (revision 87c2ce3b)
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/kdump.h>
38 #include <asm/prom.h>
39 #include <asm/processor.h>
40 #include <asm/pgtable.h>
41 #include <asm/smp.h>
42 #include <asm/elf.h>
43 #include <asm/machdep.h>
44 #include <asm/paca.h>
45 #include <asm/time.h>
46 #include <asm/cputable.h>
47 #include <asm/sections.h>
48 #include <asm/btext.h>
49 #include <asm/nvram.h>
50 #include <asm/setup.h>
51 #include <asm/system.h>
52 #include <asm/rtas.h>
53 #include <asm/iommu.h>
54 #include <asm/serial.h>
55 #include <asm/cache.h>
56 #include <asm/page.h>
57 #include <asm/mmu.h>
58 #include <asm/lmb.h>
59 #include <asm/iseries/it_lp_naca.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 
73 /*
74  * Here are some early debugging facilities. You can enable one
75  * but your kernel will not boot on anything else if you do so
76  */
77 
78 /* This one is for use on LPAR machines that support an HVC console
79  * on vterm 0
80  */
81 extern void udbg_init_debug_lpar(void);
82 /* This one is for use on Apple G5 machines
83  */
84 extern void udbg_init_pmac_realmode(void);
85 /* That's RTAS panel debug */
86 extern void call_rtas_display_status_delay(unsigned char c);
87 /* Here's maple real mode debug */
88 extern void udbg_init_maple_realmode(void);
89 
90 #define EARLY_DEBUG_INIT() do {} while(0)
91 
92 #if 0
93 #define EARLY_DEBUG_INIT() udbg_init_debug_lpar()
94 #define EARLY_DEBUG_INIT() udbg_init_maple_realmode()
95 #define EARLY_DEBUG_INIT() udbg_init_pmac_realmode()
96 #define EARLY_DEBUG_INIT()						\
97 	do { udbg_putc = call_rtas_display_status_delay; } while(0)
98 #endif
99 
100 int have_of = 1;
101 int boot_cpuid = 0;
102 int boot_cpuid_phys = 0;
103 dev_t boot_dev;
104 u64 ppc64_pft_size;
105 
106 /* Pick defaults since we might want to patch instructions
107  * before we've read this from the device tree.
108  */
109 struct ppc64_caches ppc64_caches = {
110 	.dline_size = 0x80,
111 	.log_dline_size = 7,
112 	.iline_size = 0x80,
113 	.log_iline_size = 7
114 };
115 EXPORT_SYMBOL_GPL(ppc64_caches);
116 
117 /*
118  * These are used in binfmt_elf.c to put aux entries on the stack
119  * for each elf executable being started.
120  */
121 int dcache_bsize;
122 int icache_bsize;
123 int ucache_bsize;
124 
125 /* The main machine-dep calls structure
126  */
127 struct machdep_calls ppc_md;
128 EXPORT_SYMBOL(ppc_md);
129 
130 #ifdef CONFIG_MAGIC_SYSRQ
131 unsigned long SYSRQ_KEY;
132 #endif /* CONFIG_MAGIC_SYSRQ */
133 
134 
135 static int ppc64_panic_event(struct notifier_block *, unsigned long, void *);
136 static struct notifier_block ppc64_panic_block = {
137 	.notifier_call = ppc64_panic_event,
138 	.priority = INT_MIN /* may not return; must be done last */
139 };
140 
141 #ifdef CONFIG_SMP
142 
143 static int smt_enabled_cmdline;
144 
145 /* Look for ibm,smt-enabled OF option */
146 static void check_smt_enabled(void)
147 {
148 	struct device_node *dn;
149 	char *smt_option;
150 
151 	/* Allow the command line to overrule the OF option */
152 	if (smt_enabled_cmdline)
153 		return;
154 
155 	dn = of_find_node_by_path("/options");
156 
157 	if (dn) {
158 		smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
159 
160                 if (smt_option) {
161 			if (!strcmp(smt_option, "on"))
162 				smt_enabled_at_boot = 1;
163 			else if (!strcmp(smt_option, "off"))
164 				smt_enabled_at_boot = 0;
165                 }
166         }
167 }
168 
169 /* Look for smt-enabled= cmdline option */
170 static int __init early_smt_enabled(char *p)
171 {
172 	smt_enabled_cmdline = 1;
173 
174 	if (!p)
175 		return 0;
176 
177 	if (!strcmp(p, "on") || !strcmp(p, "1"))
178 		smt_enabled_at_boot = 1;
179 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
180 		smt_enabled_at_boot = 0;
181 
182 	return 0;
183 }
184 early_param("smt-enabled", early_smt_enabled);
185 
186 #else
187 #define check_smt_enabled()
188 #endif /* CONFIG_SMP */
189 
190 extern struct machdep_calls pSeries_md;
191 extern struct machdep_calls pmac_md;
192 extern struct machdep_calls maple_md;
193 extern struct machdep_calls cell_md;
194 extern struct machdep_calls iseries_md;
195 
196 /* Ultimately, stuff them in an elf section like initcalls... */
197 static struct machdep_calls __initdata *machines[] = {
198 #ifdef CONFIG_PPC_PSERIES
199 	&pSeries_md,
200 #endif /* CONFIG_PPC_PSERIES */
201 #ifdef CONFIG_PPC_PMAC
202 	&pmac_md,
203 #endif /* CONFIG_PPC_PMAC */
204 #ifdef CONFIG_PPC_MAPLE
205 	&maple_md,
206 #endif /* CONFIG_PPC_MAPLE */
207 #ifdef CONFIG_PPC_CELL
208 	&cell_md,
209 #endif
210 #ifdef CONFIG_PPC_ISERIES
211 	&iseries_md,
212 #endif
213 	NULL
214 };
215 
216 /*
217  * Early initialization entry point. This is called by head.S
218  * with MMU translation disabled. We rely on the "feature" of
219  * the CPU that ignores the top 2 bits of the address in real
220  * mode so we can access kernel globals normally provided we
221  * only toy with things in the RMO region. From here, we do
222  * some early parsing of the device-tree to setup out LMB
223  * data structures, and allocate & initialize the hash table
224  * and segment tables so we can start running with translation
225  * enabled.
226  *
227  * It is this function which will call the probe() callback of
228  * the various platform types and copy the matching one to the
229  * global ppc_md structure. Your platform can eventually do
230  * some very early initializations from the probe() routine, but
231  * this is not recommended, be very careful as, for example, the
232  * device-tree is not accessible via normal means at this point.
233  */
234 
235 void __init early_setup(unsigned long dt_ptr)
236 {
237 	struct paca_struct *lpaca = get_paca();
238 	static struct machdep_calls **mach;
239 
240 	/*
241 	 * Enable early debugging if any specified (see top of
242 	 * this file)
243 	 */
244 	EARLY_DEBUG_INIT();
245 
246 	DBG(" -> early_setup()\n");
247 
248 	/*
249 	 * Do early initializations using the flattened device
250 	 * tree, like retreiving the physical memory map or
251 	 * calculating/retreiving the hash table size
252 	 */
253 	early_init_devtree(__va(dt_ptr));
254 
255 	/*
256 	 * Iterate all ppc_md structures until we find the proper
257 	 * one for the current machine type
258 	 */
259 	DBG("Probing machine type for platform %x...\n", _machine);
260 
261 	for (mach = machines; *mach; mach++) {
262 		if ((*mach)->probe(_machine))
263 			break;
264 	}
265 	/* What can we do if we didn't find ? */
266 	if (*mach == NULL) {
267 		DBG("No suitable machine found !\n");
268 		for (;;);
269 	}
270 	ppc_md = **mach;
271 
272 #ifdef CONFIG_CRASH_DUMP
273 	kdump_setup();
274 #endif
275 
276 	DBG("Found, Initializing memory management...\n");
277 
278 	/*
279 	 * Initialize the MMU Hash table and create the linear mapping
280 	 * of memory. Has to be done before stab/slb initialization as
281 	 * this is currently where the page size encoding is obtained
282 	 */
283 	htab_initialize();
284 
285 	/*
286 	 * Initialize stab / SLB management except on iSeries
287 	 */
288 	if (!firmware_has_feature(FW_FEATURE_ISERIES)) {
289 		if (cpu_has_feature(CPU_FTR_SLB))
290 			slb_initialize();
291 		else
292 			stab_initialize(lpaca->stab_real);
293 	}
294 
295 	DBG(" <- early_setup()\n");
296 }
297 
298 #ifdef CONFIG_SMP
299 void early_setup_secondary(void)
300 {
301 	struct paca_struct *lpaca = get_paca();
302 
303 	/* Mark enabled in PACA */
304 	lpaca->proc_enabled = 0;
305 
306 	/* Initialize hash table for that CPU */
307 	htab_initialize_secondary();
308 
309 	/* Initialize STAB/SLB. We use a virtual address as it works
310 	 * in real mode on pSeries and we want a virutal address on
311 	 * iSeries anyway
312 	 */
313 	if (cpu_has_feature(CPU_FTR_SLB))
314 		slb_initialize();
315 	else
316 		stab_initialize(lpaca->stab_addr);
317 }
318 
319 #endif /* CONFIG_SMP */
320 
321 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
322 void smp_release_cpus(void)
323 {
324 	extern unsigned long __secondary_hold_spinloop;
325 	unsigned long *ptr;
326 
327 	DBG(" -> smp_release_cpus()\n");
328 
329 	/* All secondary cpus are spinning on a common spinloop, release them
330 	 * all now so they can start to spin on their individual paca
331 	 * spinloops. For non SMP kernels, the secondary cpus never get out
332 	 * of the common spinloop.
333 	 * This is useless but harmless on iSeries, secondaries are already
334 	 * waiting on their paca spinloops. */
335 
336 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
337 			- PHYSICAL_START);
338 	*ptr = 1;
339 	mb();
340 
341 	DBG(" <- smp_release_cpus()\n");
342 }
343 #else
344 #define smp_release_cpus()
345 #endif /* CONFIG_SMP || CONFIG_KEXEC */
346 
347 /*
348  * Initialize some remaining members of the ppc64_caches and systemcfg
349  * structures
350  * (at least until we get rid of them completely). This is mostly some
351  * cache informations about the CPU that will be used by cache flush
352  * routines and/or provided to userland
353  */
354 static void __init initialize_cache_info(void)
355 {
356 	struct device_node *np;
357 	unsigned long num_cpus = 0;
358 
359 	DBG(" -> initialize_cache_info()\n");
360 
361 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
362 		num_cpus += 1;
363 
364 		/* We're assuming *all* of the CPUs have the same
365 		 * d-cache and i-cache sizes... -Peter
366 		 */
367 
368 		if ( num_cpus == 1 ) {
369 			u32 *sizep, *lsizep;
370 			u32 size, lsize;
371 			const char *dc, *ic;
372 
373 			/* Then read cache informations */
374 			if (_machine == PLATFORM_POWERMAC) {
375 				dc = "d-cache-block-size";
376 				ic = "i-cache-block-size";
377 			} else {
378 				dc = "d-cache-line-size";
379 				ic = "i-cache-line-size";
380 			}
381 
382 			size = 0;
383 			lsize = cur_cpu_spec->dcache_bsize;
384 			sizep = (u32 *)get_property(np, "d-cache-size", NULL);
385 			if (sizep != NULL)
386 				size = *sizep;
387 			lsizep = (u32 *) get_property(np, dc, NULL);
388 			if (lsizep != NULL)
389 				lsize = *lsizep;
390 			if (sizep == 0 || lsizep == 0)
391 				DBG("Argh, can't find dcache properties ! "
392 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
393 
394 			ppc64_caches.dsize = size;
395 			ppc64_caches.dline_size = lsize;
396 			ppc64_caches.log_dline_size = __ilog2(lsize);
397 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
398 
399 			size = 0;
400 			lsize = cur_cpu_spec->icache_bsize;
401 			sizep = (u32 *)get_property(np, "i-cache-size", NULL);
402 			if (sizep != NULL)
403 				size = *sizep;
404 			lsizep = (u32 *)get_property(np, ic, NULL);
405 			if (lsizep != NULL)
406 				lsize = *lsizep;
407 			if (sizep == 0 || lsizep == 0)
408 				DBG("Argh, can't find icache properties ! "
409 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
410 
411 			ppc64_caches.isize = size;
412 			ppc64_caches.iline_size = lsize;
413 			ppc64_caches.log_iline_size = __ilog2(lsize);
414 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
415 		}
416 	}
417 
418 	DBG(" <- initialize_cache_info()\n");
419 }
420 
421 
422 /*
423  * Do some initial setup of the system.  The parameters are those which
424  * were passed in from the bootloader.
425  */
426 void __init setup_system(void)
427 {
428 	DBG(" -> setup_system()\n");
429 
430 	/*
431 	 * Unflatten the device-tree passed by prom_init or kexec
432 	 */
433 	unflatten_device_tree();
434 
435 #ifdef CONFIG_KEXEC
436 	kexec_setup();	/* requires unflattened device tree. */
437 #endif
438 
439 	/*
440 	 * Fill the ppc64_caches & systemcfg structures with informations
441 	 * retrieved from the device-tree. Need to be called before
442 	 * finish_device_tree() since the later requires some of the
443 	 * informations filled up here to properly parse the interrupt
444 	 * tree.
445 	 * It also sets up the cache line sizes which allows to call
446 	 * routines like flush_icache_range (used by the hash init
447 	 * later on).
448 	 */
449 	initialize_cache_info();
450 
451 #ifdef CONFIG_PPC_RTAS
452 	/*
453 	 * Initialize RTAS if available
454 	 */
455 	rtas_initialize();
456 #endif /* CONFIG_PPC_RTAS */
457 
458 	/*
459 	 * Check if we have an initrd provided via the device-tree
460 	 */
461 	check_for_initrd();
462 
463 	/*
464 	 * Do some platform specific early initializations, that includes
465 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
466 	 * related options that will be used by finish_device_tree()
467 	 */
468 	ppc_md.init_early();
469 
470  	/*
471 	 * We can discover serial ports now since the above did setup the
472 	 * hash table management for us, thus ioremap works. We do that early
473 	 * so that further code can be debugged
474 	 */
475 #ifdef CONFIG_SERIAL_8250
476 	find_legacy_serial_ports();
477 #endif
478 
479 	/*
480 	 * "Finish" the device-tree, that is do the actual parsing of
481 	 * some of the properties like the interrupt map
482 	 */
483 	finish_device_tree();
484 
485 	/*
486 	 * Initialize xmon
487 	 */
488 #ifdef CONFIG_XMON_DEFAULT
489 	xmon_init(1);
490 #endif
491 	/*
492 	 * Register early console
493 	 */
494 	register_early_udbg_console();
495 
496 	/* Save unparsed command line copy for /proc/cmdline */
497 	strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
498 
499 	parse_early_param();
500 
501 	check_smt_enabled();
502 	smp_setup_cpu_maps();
503 
504 	/* Release secondary cpus out of their spinloops at 0x60 now that
505 	 * we can map physical -> logical CPU ids
506 	 */
507 	smp_release_cpus();
508 
509 	printk("Starting Linux PPC64 %s\n", system_utsname.version);
510 
511 	printk("-----------------------------------------------------\n");
512 	printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
513 	printk("ppc64_interrupt_controller    = 0x%ld\n",
514 	       ppc64_interrupt_controller);
515 	printk("platform                      = 0x%x\n", _machine);
516 	printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
517 	printk("ppc64_caches.dcache_line_size = 0x%x\n",
518 	       ppc64_caches.dline_size);
519 	printk("ppc64_caches.icache_line_size = 0x%x\n",
520 	       ppc64_caches.iline_size);
521 	printk("htab_address                  = 0x%p\n", htab_address);
522 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
523 #if PHYSICAL_START > 0
524 	printk("physical_start                = 0x%x\n", PHYSICAL_START);
525 #endif
526 	printk("-----------------------------------------------------\n");
527 
528 	mm_init_ppc64();
529 
530 	DBG(" <- setup_system()\n");
531 }
532 
533 static int ppc64_panic_event(struct notifier_block *this,
534                              unsigned long event, void *ptr)
535 {
536 	ppc_md.panic((char *)ptr);  /* May not return */
537 	return NOTIFY_DONE;
538 }
539 
540 #ifdef CONFIG_IRQSTACKS
541 static void __init irqstack_early_init(void)
542 {
543 	unsigned int i;
544 
545 	/*
546 	 * interrupt stacks must be under 256MB, we cannot afford to take
547 	 * SLB misses on them.
548 	 */
549 	for_each_cpu(i) {
550 		softirq_ctx[i] = (struct thread_info *)
551 			__va(lmb_alloc_base(THREAD_SIZE,
552 					    THREAD_SIZE, 0x10000000));
553 		hardirq_ctx[i] = (struct thread_info *)
554 			__va(lmb_alloc_base(THREAD_SIZE,
555 					    THREAD_SIZE, 0x10000000));
556 	}
557 }
558 #else
559 #define irqstack_early_init()
560 #endif
561 
562 /*
563  * Stack space used when we detect a bad kernel stack pointer, and
564  * early in SMP boots before relocation is enabled.
565  */
566 static void __init emergency_stack_init(void)
567 {
568 	unsigned long limit;
569 	unsigned int i;
570 
571 	/*
572 	 * Emergency stacks must be under 256MB, we cannot afford to take
573 	 * SLB misses on them. The ABI also requires them to be 128-byte
574 	 * aligned.
575 	 *
576 	 * Since we use these as temporary stacks during secondary CPU
577 	 * bringup, we need to get at them in real mode. This means they
578 	 * must also be within the RMO region.
579 	 */
580 	limit = min(0x10000000UL, lmb.rmo_size);
581 
582 	for_each_cpu(i)
583 		paca[i].emergency_sp =
584 		__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
585 }
586 
587 /*
588  * Called into from start_kernel, after lock_kernel has been called.
589  * Initializes bootmem, which is unsed to manage page allocation until
590  * mem_init is called.
591  */
592 void __init setup_arch(char **cmdline_p)
593 {
594 	extern void do_init_bootmem(void);
595 
596 	ppc64_boot_msg(0x12, "Setup Arch");
597 
598 	*cmdline_p = cmd_line;
599 
600 	/*
601 	 * Set cache line size based on type of cpu as a default.
602 	 * Systems with OF can look in the properties on the cpu node(s)
603 	 * for a possibly more accurate value.
604 	 */
605 	dcache_bsize = ppc64_caches.dline_size;
606 	icache_bsize = ppc64_caches.iline_size;
607 
608 	/* reboot on panic */
609 	panic_timeout = 180;
610 
611 	if (ppc_md.panic)
612 		notifier_chain_register(&panic_notifier_list, &ppc64_panic_block);
613 
614 	init_mm.start_code = PAGE_OFFSET;
615 	init_mm.end_code = (unsigned long) _etext;
616 	init_mm.end_data = (unsigned long) _edata;
617 	init_mm.brk = klimit;
618 
619 	irqstack_early_init();
620 	emergency_stack_init();
621 
622 	stabs_alloc();
623 
624 	/* set up the bootmem stuff with available memory */
625 	do_init_bootmem();
626 	sparse_init();
627 
628 #ifdef CONFIG_DUMMY_CONSOLE
629 	conswitchp = &dummy_con;
630 #endif
631 
632 	ppc_md.setup_arch();
633 
634 	/* Use the default idle loop if the platform hasn't provided one. */
635 	if (NULL == ppc_md.idle_loop) {
636 		ppc_md.idle_loop = default_idle;
637 		printk(KERN_INFO "Using default idle loop\n");
638 	}
639 
640 	paging_init();
641 	ppc64_boot_msg(0x15, "Setup Done");
642 }
643 
644 
645 /* ToDo: do something useful if ppc_md is not yet setup. */
646 #define PPC64_LINUX_FUNCTION 0x0f000000
647 #define PPC64_IPL_MESSAGE 0xc0000000
648 #define PPC64_TERM_MESSAGE 0xb0000000
649 
650 static void ppc64_do_msg(unsigned int src, const char *msg)
651 {
652 	if (ppc_md.progress) {
653 		char buf[128];
654 
655 		sprintf(buf, "%08X\n", src);
656 		ppc_md.progress(buf, 0);
657 		snprintf(buf, 128, "%s", msg);
658 		ppc_md.progress(buf, 0);
659 	}
660 }
661 
662 /* Print a boot progress message. */
663 void ppc64_boot_msg(unsigned int src, const char *msg)
664 {
665 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
666 	printk("[boot]%04x %s\n", src, msg);
667 }
668 
669 /* Print a termination message (print only -- does not stop the kernel) */
670 void ppc64_terminate_msg(unsigned int src, const char *msg)
671 {
672 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
673 	printk("[terminate]%04x %s\n", src, msg);
674 }
675 
676 int check_legacy_ioport(unsigned long base_port)
677 {
678 	if (ppc_md.check_legacy_ioport == NULL)
679 		return 0;
680 	return ppc_md.check_legacy_ioport(base_port);
681 }
682 EXPORT_SYMBOL(check_legacy_ioport);
683 
684 void cpu_die(void)
685 {
686 	if (ppc_md.cpu_die)
687 		ppc_md.cpu_die();
688 }
689