xref: /linux/arch/powerpc/kernel/setup_64.c (revision ccea15f45eb0ab12d658f88b5d4be005cb2bb1a7)
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 dev_t boot_dev;
77 u64 ppc64_pft_size;
78 
79 /* Pick defaults since we might want to patch instructions
80  * before we've read this from the device tree.
81  */
82 struct ppc64_caches ppc64_caches = {
83 	.dline_size = 0x80,
84 	.log_dline_size = 7,
85 	.iline_size = 0x80,
86 	.log_iline_size = 7
87 };
88 EXPORT_SYMBOL_GPL(ppc64_caches);
89 
90 /*
91  * These are used in binfmt_elf.c to put aux entries on the stack
92  * for each elf executable being started.
93  */
94 int dcache_bsize;
95 int icache_bsize;
96 int ucache_bsize;
97 
98 #ifdef CONFIG_MAGIC_SYSRQ
99 unsigned long SYSRQ_KEY;
100 #endif /* CONFIG_MAGIC_SYSRQ */
101 
102 
103 static int ppc64_panic_event(struct notifier_block *, unsigned long, void *);
104 static struct notifier_block ppc64_panic_block = {
105 	.notifier_call = ppc64_panic_event,
106 	.priority = INT_MIN /* may not return; must be done last */
107 };
108 
109 #ifdef CONFIG_SMP
110 
111 static int smt_enabled_cmdline;
112 
113 /* Look for ibm,smt-enabled OF option */
114 static void check_smt_enabled(void)
115 {
116 	struct device_node *dn;
117 	char *smt_option;
118 
119 	/* Allow the command line to overrule the OF option */
120 	if (smt_enabled_cmdline)
121 		return;
122 
123 	dn = of_find_node_by_path("/options");
124 
125 	if (dn) {
126 		smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
127 
128                 if (smt_option) {
129 			if (!strcmp(smt_option, "on"))
130 				smt_enabled_at_boot = 1;
131 			else if (!strcmp(smt_option, "off"))
132 				smt_enabled_at_boot = 0;
133                 }
134         }
135 }
136 
137 /* Look for smt-enabled= cmdline option */
138 static int __init early_smt_enabled(char *p)
139 {
140 	smt_enabled_cmdline = 1;
141 
142 	if (!p)
143 		return 0;
144 
145 	if (!strcmp(p, "on") || !strcmp(p, "1"))
146 		smt_enabled_at_boot = 1;
147 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
148 		smt_enabled_at_boot = 0;
149 
150 	return 0;
151 }
152 early_param("smt-enabled", early_smt_enabled);
153 
154 #else
155 #define check_smt_enabled()
156 #endif /* CONFIG_SMP */
157 
158 /*
159  * Early initialization entry point. This is called by head.S
160  * with MMU translation disabled. We rely on the "feature" of
161  * the CPU that ignores the top 2 bits of the address in real
162  * mode so we can access kernel globals normally provided we
163  * only toy with things in the RMO region. From here, we do
164  * some early parsing of the device-tree to setup out LMB
165  * data structures, and allocate & initialize the hash table
166  * and segment tables so we can start running with translation
167  * enabled.
168  *
169  * It is this function which will call the probe() callback of
170  * the various platform types and copy the matching one to the
171  * global ppc_md structure. Your platform can eventually do
172  * some very early initializations from the probe() routine, but
173  * this is not recommended, be very careful as, for example, the
174  * device-tree is not accessible via normal means at this point.
175  */
176 
177 void __init early_setup(unsigned long dt_ptr)
178 {
179 	/* Enable early debugging if any specified (see udbg.h) */
180 	udbg_early_init();
181 
182  	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
183 
184 	/*
185 	 * Do early initializations using the flattened device
186 	 * tree, like retreiving the physical memory map or
187 	 * calculating/retreiving the hash table size
188 	 */
189 	early_init_devtree(__va(dt_ptr));
190 
191 	/* Now we know the logical id of our boot cpu, setup the paca. */
192 	setup_boot_paca();
193 
194 	/* Fix up paca fields required for the boot cpu */
195 	get_paca()->cpu_start = 1;
196 	get_paca()->stab_real = __pa((u64)&initial_stab);
197 	get_paca()->stab_addr = (u64)&initial_stab;
198 
199 	/* Probe the machine type */
200 	probe_machine();
201 
202 #ifdef CONFIG_CRASH_DUMP
203 	kdump_setup();
204 #endif
205 
206 	DBG("Found, Initializing memory management...\n");
207 
208 	/*
209 	 * Initialize the MMU Hash table and create the linear mapping
210 	 * of memory. Has to be done before stab/slb initialization as
211 	 * this is currently where the page size encoding is obtained
212 	 */
213 	htab_initialize();
214 
215 	/*
216 	 * Initialize stab / SLB management except on iSeries
217 	 */
218 	if (cpu_has_feature(CPU_FTR_SLB))
219 		slb_initialize();
220 	else if (!firmware_has_feature(FW_FEATURE_ISERIES))
221 		stab_initialize(get_paca()->stab_real);
222 
223 	DBG(" <- early_setup()\n");
224 }
225 
226 #ifdef CONFIG_SMP
227 void early_setup_secondary(void)
228 {
229 	struct paca_struct *lpaca = get_paca();
230 
231 	/* Mark enabled in PACA */
232 	lpaca->proc_enabled = 0;
233 
234 	/* Initialize hash table for that CPU */
235 	htab_initialize_secondary();
236 
237 	/* Initialize STAB/SLB. We use a virtual address as it works
238 	 * in real mode on pSeries and we want a virutal address on
239 	 * iSeries anyway
240 	 */
241 	if (cpu_has_feature(CPU_FTR_SLB))
242 		slb_initialize();
243 	else
244 		stab_initialize(lpaca->stab_addr);
245 }
246 
247 #endif /* CONFIG_SMP */
248 
249 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
250 void smp_release_cpus(void)
251 {
252 	extern unsigned long __secondary_hold_spinloop;
253 	unsigned long *ptr;
254 
255 	DBG(" -> smp_release_cpus()\n");
256 
257 	/* All secondary cpus are spinning on a common spinloop, release them
258 	 * all now so they can start to spin on their individual paca
259 	 * spinloops. For non SMP kernels, the secondary cpus never get out
260 	 * of the common spinloop.
261 	 * This is useless but harmless on iSeries, secondaries are already
262 	 * waiting on their paca spinloops. */
263 
264 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
265 			- PHYSICAL_START);
266 	*ptr = 1;
267 	mb();
268 
269 	DBG(" <- smp_release_cpus()\n");
270 }
271 #endif /* CONFIG_SMP || CONFIG_KEXEC */
272 
273 /*
274  * Initialize some remaining members of the ppc64_caches and systemcfg
275  * structures
276  * (at least until we get rid of them completely). This is mostly some
277  * cache informations about the CPU that will be used by cache flush
278  * routines and/or provided to userland
279  */
280 static void __init initialize_cache_info(void)
281 {
282 	struct device_node *np;
283 	unsigned long num_cpus = 0;
284 
285 	DBG(" -> initialize_cache_info()\n");
286 
287 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
288 		num_cpus += 1;
289 
290 		/* We're assuming *all* of the CPUs have the same
291 		 * d-cache and i-cache sizes... -Peter
292 		 */
293 
294 		if ( num_cpus == 1 ) {
295 			u32 *sizep, *lsizep;
296 			u32 size, lsize;
297 			const char *dc, *ic;
298 
299 			/* Then read cache informations */
300 			if (machine_is(powermac)) {
301 				dc = "d-cache-block-size";
302 				ic = "i-cache-block-size";
303 			} else {
304 				dc = "d-cache-line-size";
305 				ic = "i-cache-line-size";
306 			}
307 
308 			size = 0;
309 			lsize = cur_cpu_spec->dcache_bsize;
310 			sizep = (u32 *)get_property(np, "d-cache-size", NULL);
311 			if (sizep != NULL)
312 				size = *sizep;
313 			lsizep = (u32 *) get_property(np, dc, NULL);
314 			if (lsizep != NULL)
315 				lsize = *lsizep;
316 			if (sizep == 0 || lsizep == 0)
317 				DBG("Argh, can't find dcache properties ! "
318 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
319 
320 			ppc64_caches.dsize = size;
321 			ppc64_caches.dline_size = lsize;
322 			ppc64_caches.log_dline_size = __ilog2(lsize);
323 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
324 
325 			size = 0;
326 			lsize = cur_cpu_spec->icache_bsize;
327 			sizep = (u32 *)get_property(np, "i-cache-size", NULL);
328 			if (sizep != NULL)
329 				size = *sizep;
330 			lsizep = (u32 *)get_property(np, ic, NULL);
331 			if (lsizep != NULL)
332 				lsize = *lsizep;
333 			if (sizep == 0 || lsizep == 0)
334 				DBG("Argh, can't find icache properties ! "
335 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
336 
337 			ppc64_caches.isize = size;
338 			ppc64_caches.iline_size = lsize;
339 			ppc64_caches.log_iline_size = __ilog2(lsize);
340 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
341 		}
342 	}
343 
344 	DBG(" <- initialize_cache_info()\n");
345 }
346 
347 
348 /*
349  * Do some initial setup of the system.  The parameters are those which
350  * were passed in from the bootloader.
351  */
352 void __init setup_system(void)
353 {
354 	DBG(" -> setup_system()\n");
355 
356 #ifdef CONFIG_KEXEC
357 	kdump_move_device_tree();
358 #endif
359 	/*
360 	 * Unflatten the device-tree passed by prom_init or kexec
361 	 */
362 	unflatten_device_tree();
363 
364 #ifdef CONFIG_KEXEC
365 	kexec_setup();	/* requires unflattened device tree. */
366 #endif
367 
368 	/*
369 	 * Fill the ppc64_caches & systemcfg structures with informations
370 	 * retrieved from the device-tree. Need to be called before
371 	 * finish_device_tree() since the later requires some of the
372 	 * informations filled up here to properly parse the interrupt
373 	 * tree.
374 	 * It also sets up the cache line sizes which allows to call
375 	 * routines like flush_icache_range (used by the hash init
376 	 * later on).
377 	 */
378 	initialize_cache_info();
379 
380 #ifdef CONFIG_PPC_RTAS
381 	/*
382 	 * Initialize RTAS if available
383 	 */
384 	rtas_initialize();
385 #endif /* CONFIG_PPC_RTAS */
386 
387 	/*
388 	 * Check if we have an initrd provided via the device-tree
389 	 */
390 	check_for_initrd();
391 
392 	/*
393 	 * Do some platform specific early initializations, that includes
394 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
395 	 * related options that will be used by finish_device_tree()
396 	 */
397 	ppc_md.init_early();
398 
399  	/*
400 	 * We can discover serial ports now since the above did setup the
401 	 * hash table management for us, thus ioremap works. We do that early
402 	 * so that further code can be debugged
403 	 */
404 	find_legacy_serial_ports();
405 
406 	/*
407 	 * "Finish" the device-tree, that is do the actual parsing of
408 	 * some of the properties like the interrupt map
409 	 */
410 	finish_device_tree();
411 
412 	/*
413 	 * Initialize xmon
414 	 */
415 #ifdef CONFIG_XMON_DEFAULT
416 	xmon_init(1);
417 #endif
418 	/*
419 	 * Register early console
420 	 */
421 	register_early_udbg_console();
422 
423 	/* Save unparsed command line copy for /proc/cmdline */
424 	strlcpy(saved_command_line, cmd_line, COMMAND_LINE_SIZE);
425 
426 	parse_early_param();
427 
428 	check_smt_enabled();
429 	smp_setup_cpu_maps();
430 
431 #ifdef CONFIG_SMP
432 	/* Release secondary cpus out of their spinloops at 0x60 now that
433 	 * we can map physical -> logical CPU ids
434 	 */
435 	smp_release_cpus();
436 #endif
437 
438 	printk("Starting Linux PPC64 %s\n", system_utsname.version);
439 
440 	printk("-----------------------------------------------------\n");
441 	printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
442 	printk("ppc64_interrupt_controller    = 0x%ld\n",
443 	       ppc64_interrupt_controller);
444 	printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
445 	printk("ppc64_caches.dcache_line_size = 0x%x\n",
446 	       ppc64_caches.dline_size);
447 	printk("ppc64_caches.icache_line_size = 0x%x\n",
448 	       ppc64_caches.iline_size);
449 	printk("htab_address                  = 0x%p\n", htab_address);
450 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
451 #if PHYSICAL_START > 0
452 	printk("physical_start                = 0x%x\n", PHYSICAL_START);
453 #endif
454 	printk("-----------------------------------------------------\n");
455 
456 	DBG(" <- setup_system()\n");
457 }
458 
459 static int ppc64_panic_event(struct notifier_block *this,
460                              unsigned long event, void *ptr)
461 {
462 	ppc_md.panic((char *)ptr);  /* May not return */
463 	return NOTIFY_DONE;
464 }
465 
466 #ifdef CONFIG_IRQSTACKS
467 static void __init irqstack_early_init(void)
468 {
469 	unsigned int i;
470 
471 	/*
472 	 * interrupt stacks must be under 256MB, we cannot afford to take
473 	 * SLB misses on them.
474 	 */
475 	for_each_possible_cpu(i) {
476 		softirq_ctx[i] = (struct thread_info *)
477 			__va(lmb_alloc_base(THREAD_SIZE,
478 					    THREAD_SIZE, 0x10000000));
479 		hardirq_ctx[i] = (struct thread_info *)
480 			__va(lmb_alloc_base(THREAD_SIZE,
481 					    THREAD_SIZE, 0x10000000));
482 	}
483 }
484 #else
485 #define irqstack_early_init()
486 #endif
487 
488 /*
489  * Stack space used when we detect a bad kernel stack pointer, and
490  * early in SMP boots before relocation is enabled.
491  */
492 static void __init emergency_stack_init(void)
493 {
494 	unsigned long limit;
495 	unsigned int i;
496 
497 	/*
498 	 * Emergency stacks must be under 256MB, we cannot afford to take
499 	 * SLB misses on them. The ABI also requires them to be 128-byte
500 	 * aligned.
501 	 *
502 	 * Since we use these as temporary stacks during secondary CPU
503 	 * bringup, we need to get at them in real mode. This means they
504 	 * must also be within the RMO region.
505 	 */
506 	limit = min(0x10000000UL, lmb.rmo_size);
507 
508 	for_each_possible_cpu(i)
509 		paca[i].emergency_sp =
510 		__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
511 }
512 
513 /*
514  * Called into from start_kernel, after lock_kernel has been called.
515  * Initializes bootmem, which is unsed to manage page allocation until
516  * mem_init is called.
517  */
518 void __init setup_arch(char **cmdline_p)
519 {
520 	extern void do_init_bootmem(void);
521 
522 	ppc64_boot_msg(0x12, "Setup Arch");
523 
524 	*cmdline_p = cmd_line;
525 
526 	/*
527 	 * Set cache line size based on type of cpu as a default.
528 	 * Systems with OF can look in the properties on the cpu node(s)
529 	 * for a possibly more accurate value.
530 	 */
531 	dcache_bsize = ppc64_caches.dline_size;
532 	icache_bsize = ppc64_caches.iline_size;
533 
534 	/* reboot on panic */
535 	panic_timeout = 180;
536 
537 	if (ppc_md.panic)
538 		atomic_notifier_chain_register(&panic_notifier_list,
539 				&ppc64_panic_block);
540 
541 	init_mm.start_code = PAGE_OFFSET;
542 	init_mm.end_code = (unsigned long) _etext;
543 	init_mm.end_data = (unsigned long) _edata;
544 	init_mm.brk = klimit;
545 
546 	irqstack_early_init();
547 	emergency_stack_init();
548 
549 	stabs_alloc();
550 
551 	/* set up the bootmem stuff with available memory */
552 	do_init_bootmem();
553 	sparse_init();
554 
555 #ifdef CONFIG_DUMMY_CONSOLE
556 	conswitchp = &dummy_con;
557 #endif
558 
559 	ppc_md.setup_arch();
560 
561 	paging_init();
562 	ppc64_boot_msg(0x15, "Setup Done");
563 }
564 
565 
566 /* ToDo: do something useful if ppc_md is not yet setup. */
567 #define PPC64_LINUX_FUNCTION 0x0f000000
568 #define PPC64_IPL_MESSAGE 0xc0000000
569 #define PPC64_TERM_MESSAGE 0xb0000000
570 
571 static void ppc64_do_msg(unsigned int src, const char *msg)
572 {
573 	if (ppc_md.progress) {
574 		char buf[128];
575 
576 		sprintf(buf, "%08X\n", src);
577 		ppc_md.progress(buf, 0);
578 		snprintf(buf, 128, "%s", msg);
579 		ppc_md.progress(buf, 0);
580 	}
581 }
582 
583 /* Print a boot progress message. */
584 void ppc64_boot_msg(unsigned int src, const char *msg)
585 {
586 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
587 	printk("[boot]%04x %s\n", src, msg);
588 }
589 
590 /* Print a termination message (print only -- does not stop the kernel) */
591 void ppc64_terminate_msg(unsigned int src, const char *msg)
592 {
593 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
594 	printk("[terminate]%04x %s\n", src, msg);
595 }
596 
597 int check_legacy_ioport(unsigned long base_port)
598 {
599 	if (ppc_md.check_legacy_ioport == NULL)
600 		return 0;
601 	return ppc_md.check_legacy_ioport(base_port);
602 }
603 EXPORT_SYMBOL(check_legacy_ioport);
604 
605 void cpu_die(void)
606 {
607 	if (ppc_md.cpu_die)
608 		ppc_md.cpu_die();
609 }
610 
611 #ifdef CONFIG_SMP
612 void __init setup_per_cpu_areas(void)
613 {
614 	int i;
615 	unsigned long size;
616 	char *ptr;
617 
618 	/* Copy section for each CPU (we discard the original) */
619 	size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
620 #ifdef CONFIG_MODULES
621 	if (size < PERCPU_ENOUGH_ROOM)
622 		size = PERCPU_ENOUGH_ROOM;
623 #endif
624 
625 	for_each_possible_cpu(i) {
626 		ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
627 		if (!ptr)
628 			panic("Cannot allocate cpu data for CPU %d\n", i);
629 
630 		paca[i].data_offset = ptr - __per_cpu_start;
631 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
632 	}
633 }
634 #endif
635