xref: /linux/arch/powerpc/kernel/setup_64.c (revision 273b281fa22c293963ee3e6eec418f5dda2dbc83)
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 #include <asm/swiotlb.h>
65 #include <asm/mmu_context.h>
66 
67 #include "setup.h"
68 
69 #ifdef DEBUG
70 #define DBG(fmt...) udbg_printf(fmt)
71 #else
72 #define DBG(fmt...)
73 #endif
74 
75 int boot_cpuid = 0;
76 u64 ppc64_pft_size;
77 
78 /* Pick defaults since we might want to patch instructions
79  * before we've read this from the device tree.
80  */
81 struct ppc64_caches ppc64_caches = {
82 	.dline_size = 0x40,
83 	.log_dline_size = 6,
84 	.iline_size = 0x40,
85 	.log_iline_size = 6
86 };
87 EXPORT_SYMBOL_GPL(ppc64_caches);
88 
89 /*
90  * These are used in binfmt_elf.c to put aux entries on the stack
91  * for each elf executable being started.
92  */
93 int dcache_bsize;
94 int icache_bsize;
95 int ucache_bsize;
96 
97 #ifdef CONFIG_SMP
98 
99 static int smt_enabled_cmdline;
100 
101 /* Look for ibm,smt-enabled OF option */
102 static void check_smt_enabled(void)
103 {
104 	struct device_node *dn;
105 	const char *smt_option;
106 
107 	/* Allow the command line to overrule the OF option */
108 	if (smt_enabled_cmdline)
109 		return;
110 
111 	dn = of_find_node_by_path("/options");
112 
113 	if (dn) {
114 		smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
115 
116                 if (smt_option) {
117 			if (!strcmp(smt_option, "on"))
118 				smt_enabled_at_boot = 1;
119 			else if (!strcmp(smt_option, "off"))
120 				smt_enabled_at_boot = 0;
121                 }
122         }
123 }
124 
125 /* Look for smt-enabled= cmdline option */
126 static int __init early_smt_enabled(char *p)
127 {
128 	smt_enabled_cmdline = 1;
129 
130 	if (!p)
131 		return 0;
132 
133 	if (!strcmp(p, "on") || !strcmp(p, "1"))
134 		smt_enabled_at_boot = 1;
135 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
136 		smt_enabled_at_boot = 0;
137 
138 	return 0;
139 }
140 early_param("smt-enabled", early_smt_enabled);
141 
142 #else
143 #define check_smt_enabled()
144 #endif /* CONFIG_SMP */
145 
146 /* Put the paca pointer into r13 and SPRG_PACA */
147 void __init setup_paca(int cpu)
148 {
149 	local_paca = &paca[cpu];
150 	mtspr(SPRN_SPRG_PACA, local_paca);
151 #ifdef CONFIG_PPC_BOOK3E
152 	mtspr(SPRN_SPRG_TLB_EXFRAME, local_paca->extlb);
153 #endif
154 }
155 
156 /*
157  * Early initialization entry point. This is called by head.S
158  * with MMU translation disabled. We rely on the "feature" of
159  * the CPU that ignores the top 2 bits of the address in real
160  * mode so we can access kernel globals normally provided we
161  * only toy with things in the RMO region. From here, we do
162  * some early parsing of the device-tree to setup out LMB
163  * data structures, and allocate & initialize the hash table
164  * and segment tables so we can start running with translation
165  * enabled.
166  *
167  * It is this function which will call the probe() callback of
168  * the various platform types and copy the matching one to the
169  * global ppc_md structure. Your platform can eventually do
170  * some very early initializations from the probe() routine, but
171  * this is not recommended, be very careful as, for example, the
172  * device-tree is not accessible via normal means at this point.
173  */
174 
175 void __init early_setup(unsigned long dt_ptr)
176 {
177 	/* -------- printk is _NOT_ safe to use here ! ------- */
178 
179 	/* Fill in any unititialised pacas */
180 	initialise_pacas();
181 
182 	/* Identify CPU type */
183 	identify_cpu(0, mfspr(SPRN_PVR));
184 
185 	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
186 	setup_paca(0);
187 
188 	/* Initialize lockdep early or else spinlocks will blow */
189 	lockdep_init();
190 
191 	/* -------- printk is now safe to use ------- */
192 
193 	/* Enable early debugging if any specified (see udbg.h) */
194 	udbg_early_init();
195 
196  	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
197 
198 	/*
199 	 * Do early initialization using the flattened device
200 	 * tree, such as retrieving the physical memory map or
201 	 * calculating/retrieving the hash table size.
202 	 */
203 	early_init_devtree(__va(dt_ptr));
204 
205 	/* Now we know the logical id of our boot cpu, setup the paca. */
206 	setup_paca(boot_cpuid);
207 
208 	/* Fix up paca fields required for the boot cpu */
209 	get_paca()->cpu_start = 1;
210 
211 	/* Probe the machine type */
212 	probe_machine();
213 
214 	setup_kdump_trampoline();
215 
216 	DBG("Found, Initializing memory management...\n");
217 
218 	/* Initialize the hash table or TLB handling */
219 	early_init_mmu();
220 
221 	DBG(" <- early_setup()\n");
222 }
223 
224 #ifdef CONFIG_SMP
225 void early_setup_secondary(void)
226 {
227 	/* Mark interrupts enabled in PACA */
228 	get_paca()->soft_enabled = 0;
229 
230 	/* Initialize the hash table or TLB handling */
231 	early_init_mmu_secondary();
232 }
233 
234 #endif /* CONFIG_SMP */
235 
236 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
237 void smp_release_cpus(void)
238 {
239 	unsigned long *ptr;
240 
241 	DBG(" -> smp_release_cpus()\n");
242 
243 	/* All secondary cpus are spinning on a common spinloop, release them
244 	 * all now so they can start to spin on their individual paca
245 	 * spinloops. For non SMP kernels, the secondary cpus never get out
246 	 * of the common spinloop.
247 	 */
248 
249 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
250 			- PHYSICAL_START);
251 	*ptr = __pa(generic_secondary_smp_init);
252 	mb();
253 
254 	DBG(" <- smp_release_cpus()\n");
255 }
256 #endif /* CONFIG_SMP || CONFIG_KEXEC */
257 
258 /*
259  * Initialize some remaining members of the ppc64_caches and systemcfg
260  * structures
261  * (at least until we get rid of them completely). This is mostly some
262  * cache informations about the CPU that will be used by cache flush
263  * routines and/or provided to userland
264  */
265 static void __init initialize_cache_info(void)
266 {
267 	struct device_node *np;
268 	unsigned long num_cpus = 0;
269 
270 	DBG(" -> initialize_cache_info()\n");
271 
272 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
273 		num_cpus += 1;
274 
275 		/* We're assuming *all* of the CPUs have the same
276 		 * d-cache and i-cache sizes... -Peter
277 		 */
278 
279 		if ( num_cpus == 1 ) {
280 			const u32 *sizep, *lsizep;
281 			u32 size, lsize;
282 
283 			size = 0;
284 			lsize = cur_cpu_spec->dcache_bsize;
285 			sizep = of_get_property(np, "d-cache-size", NULL);
286 			if (sizep != NULL)
287 				size = *sizep;
288 			lsizep = of_get_property(np, "d-cache-block-size", NULL);
289 			/* fallback if block size missing */
290 			if (lsizep == NULL)
291 				lsizep = of_get_property(np, "d-cache-line-size", NULL);
292 			if (lsizep != NULL)
293 				lsize = *lsizep;
294 			if (sizep == 0 || lsizep == 0)
295 				DBG("Argh, can't find dcache properties ! "
296 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
297 
298 			ppc64_caches.dsize = size;
299 			ppc64_caches.dline_size = lsize;
300 			ppc64_caches.log_dline_size = __ilog2(lsize);
301 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
302 
303 			size = 0;
304 			lsize = cur_cpu_spec->icache_bsize;
305 			sizep = of_get_property(np, "i-cache-size", NULL);
306 			if (sizep != NULL)
307 				size = *sizep;
308 			lsizep = of_get_property(np, "i-cache-block-size", NULL);
309 			if (lsizep == NULL)
310 				lsizep = of_get_property(np, "i-cache-line-size", NULL);
311 			if (lsizep != NULL)
312 				lsize = *lsizep;
313 			if (sizep == 0 || lsizep == 0)
314 				DBG("Argh, can't find icache properties ! "
315 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
316 
317 			ppc64_caches.isize = size;
318 			ppc64_caches.iline_size = lsize;
319 			ppc64_caches.log_iline_size = __ilog2(lsize);
320 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
321 		}
322 	}
323 
324 	DBG(" <- initialize_cache_info()\n");
325 }
326 
327 
328 /*
329  * Do some initial setup of the system.  The parameters are those which
330  * were passed in from the bootloader.
331  */
332 void __init setup_system(void)
333 {
334 	DBG(" -> setup_system()\n");
335 
336 	/* Apply the CPUs-specific and firmware specific fixups to kernel
337 	 * text (nop out sections not relevant to this CPU or this firmware)
338 	 */
339 	do_feature_fixups(cur_cpu_spec->cpu_features,
340 			  &__start___ftr_fixup, &__stop___ftr_fixup);
341 	do_feature_fixups(cur_cpu_spec->mmu_features,
342 			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
343 	do_feature_fixups(powerpc_firmware_features,
344 			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
345 	do_lwsync_fixups(cur_cpu_spec->cpu_features,
346 			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
347 
348 	/*
349 	 * Unflatten the device-tree passed by prom_init or kexec
350 	 */
351 	unflatten_device_tree();
352 
353 	/*
354 	 * Fill the ppc64_caches & systemcfg structures with informations
355  	 * retrieved from the device-tree.
356 	 */
357 	initialize_cache_info();
358 
359 	/*
360 	 * Initialize irq remapping subsystem
361 	 */
362 	irq_early_init();
363 
364 #ifdef CONFIG_PPC_RTAS
365 	/*
366 	 * Initialize RTAS if available
367 	 */
368 	rtas_initialize();
369 #endif /* CONFIG_PPC_RTAS */
370 
371 	/*
372 	 * Check if we have an initrd provided via the device-tree
373 	 */
374 	check_for_initrd();
375 
376 	/*
377 	 * Do some platform specific early initializations, that includes
378 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
379 	 * related options that will be used by finish_device_tree()
380 	 */
381 	if (ppc_md.init_early)
382 		ppc_md.init_early();
383 
384  	/*
385 	 * We can discover serial ports now since the above did setup the
386 	 * hash table management for us, thus ioremap works. We do that early
387 	 * so that further code can be debugged
388 	 */
389 	find_legacy_serial_ports();
390 
391 	/*
392 	 * Register early console
393 	 */
394 	register_early_udbg_console();
395 
396 	/*
397 	 * Initialize xmon
398 	 */
399 	xmon_setup();
400 
401 	check_smt_enabled();
402 	smp_setup_cpu_maps();
403 
404 #ifdef CONFIG_SMP
405 	/* Release secondary cpus out of their spinloops at 0x60 now that
406 	 * we can map physical -> logical CPU ids
407 	 */
408 	smp_release_cpus();
409 #endif
410 
411 	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
412 
413 	printk("-----------------------------------------------------\n");
414 	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
415 	printk("physicalMemorySize            = 0x%llx\n", lmb_phys_mem_size());
416 	if (ppc64_caches.dline_size != 0x80)
417 		printk("ppc64_caches.dcache_line_size = 0x%x\n",
418 		       ppc64_caches.dline_size);
419 	if (ppc64_caches.iline_size != 0x80)
420 		printk("ppc64_caches.icache_line_size = 0x%x\n",
421 		       ppc64_caches.iline_size);
422 #ifdef CONFIG_PPC_STD_MMU_64
423 	if (htab_address)
424 		printk("htab_address                  = 0x%p\n", htab_address);
425 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
426 #endif /* CONFIG_PPC_STD_MMU_64 */
427 	if (PHYSICAL_START > 0)
428 		printk("physical_start                = 0x%llx\n",
429 		       (unsigned long long)PHYSICAL_START);
430 	printk("-----------------------------------------------------\n");
431 
432 	DBG(" <- setup_system()\n");
433 }
434 
435 #ifdef CONFIG_IRQSTACKS
436 static void __init irqstack_early_init(void)
437 {
438 	unsigned int i;
439 
440 	/*
441 	 * interrupt stacks must be under 256MB, we cannot afford to take
442 	 * SLB misses on them.
443 	 */
444 	for_each_possible_cpu(i) {
445 		softirq_ctx[i] = (struct thread_info *)
446 			__va(lmb_alloc_base(THREAD_SIZE,
447 					    THREAD_SIZE, 0x10000000));
448 		hardirq_ctx[i] = (struct thread_info *)
449 			__va(lmb_alloc_base(THREAD_SIZE,
450 					    THREAD_SIZE, 0x10000000));
451 	}
452 }
453 #else
454 #define irqstack_early_init()
455 #endif
456 
457 #ifdef CONFIG_PPC_BOOK3E
458 static void __init exc_lvl_early_init(void)
459 {
460 	unsigned int i;
461 
462 	for_each_possible_cpu(i) {
463 		critirq_ctx[i] = (struct thread_info *)
464 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
465 		dbgirq_ctx[i] = (struct thread_info *)
466 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
467 		mcheckirq_ctx[i] = (struct thread_info *)
468 			__va(lmb_alloc(THREAD_SIZE, THREAD_SIZE));
469 	}
470 }
471 #else
472 #define exc_lvl_early_init()
473 #endif
474 
475 /*
476  * Stack space used when we detect a bad kernel stack pointer, and
477  * early in SMP boots before relocation is enabled.
478  */
479 static void __init emergency_stack_init(void)
480 {
481 	unsigned long limit;
482 	unsigned int i;
483 
484 	/*
485 	 * Emergency stacks must be under 256MB, we cannot afford to take
486 	 * SLB misses on them. The ABI also requires them to be 128-byte
487 	 * aligned.
488 	 *
489 	 * Since we use these as temporary stacks during secondary CPU
490 	 * bringup, we need to get at them in real mode. This means they
491 	 * must also be within the RMO region.
492 	 */
493 	limit = min(0x10000000ULL, lmb.rmo_size);
494 
495 	for_each_possible_cpu(i) {
496 		unsigned long sp;
497 		sp  = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
498 		sp += THREAD_SIZE;
499 		paca[i].emergency_sp = __va(sp);
500 	}
501 }
502 
503 /*
504  * Called into from start_kernel, after lock_kernel has been called.
505  * Initializes bootmem, which is unsed to manage page allocation until
506  * mem_init is called.
507  */
508 void __init setup_arch(char **cmdline_p)
509 {
510 	ppc64_boot_msg(0x12, "Setup Arch");
511 
512 	*cmdline_p = cmd_line;
513 
514 	/*
515 	 * Set cache line size based on type of cpu as a default.
516 	 * Systems with OF can look in the properties on the cpu node(s)
517 	 * for a possibly more accurate value.
518 	 */
519 	dcache_bsize = ppc64_caches.dline_size;
520 	icache_bsize = ppc64_caches.iline_size;
521 
522 	/* reboot on panic */
523 	panic_timeout = 180;
524 
525 	if (ppc_md.panic)
526 		setup_panic();
527 
528 	init_mm.start_code = (unsigned long)_stext;
529 	init_mm.end_code = (unsigned long) _etext;
530 	init_mm.end_data = (unsigned long) _edata;
531 	init_mm.brk = klimit;
532 
533 	irqstack_early_init();
534 	exc_lvl_early_init();
535 	emergency_stack_init();
536 
537 #ifdef CONFIG_PPC_STD_MMU_64
538 	stabs_alloc();
539 #endif
540 	/* set up the bootmem stuff with available memory */
541 	do_init_bootmem();
542 	sparse_init();
543 
544 #ifdef CONFIG_DUMMY_CONSOLE
545 	conswitchp = &dummy_con;
546 #endif
547 
548 	if (ppc_md.setup_arch)
549 		ppc_md.setup_arch();
550 
551 #ifdef CONFIG_SWIOTLB
552 	if (ppc_swiotlb_enable)
553 		swiotlb_init(1);
554 #endif
555 
556 	paging_init();
557 
558 	/* Initialize the MMU context management stuff */
559 	mmu_context_init();
560 
561 	ppc64_boot_msg(0x15, "Setup Done");
562 }
563 
564 
565 /* ToDo: do something useful if ppc_md is not yet setup. */
566 #define PPC64_LINUX_FUNCTION 0x0f000000
567 #define PPC64_IPL_MESSAGE 0xc0000000
568 #define PPC64_TERM_MESSAGE 0xb0000000
569 
570 static void ppc64_do_msg(unsigned int src, const char *msg)
571 {
572 	if (ppc_md.progress) {
573 		char buf[128];
574 
575 		sprintf(buf, "%08X\n", src);
576 		ppc_md.progress(buf, 0);
577 		snprintf(buf, 128, "%s", msg);
578 		ppc_md.progress(buf, 0);
579 	}
580 }
581 
582 /* Print a boot progress message. */
583 void ppc64_boot_msg(unsigned int src, const char *msg)
584 {
585 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
586 	printk("[boot]%04x %s\n", src, msg);
587 }
588 
589 void cpu_die(void)
590 {
591 	if (ppc_md.cpu_die)
592 		ppc_md.cpu_die();
593 }
594 
595 #ifdef CONFIG_SMP
596 #define PCPU_DYN_SIZE		()
597 
598 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
599 {
600 	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
601 				    __pa(MAX_DMA_ADDRESS));
602 }
603 
604 static void __init pcpu_fc_free(void *ptr, size_t size)
605 {
606 	free_bootmem(__pa(ptr), size);
607 }
608 
609 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
610 {
611 	if (cpu_to_node(from) == cpu_to_node(to))
612 		return LOCAL_DISTANCE;
613 	else
614 		return REMOTE_DISTANCE;
615 }
616 
617 void __init setup_per_cpu_areas(void)
618 {
619 	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
620 	size_t atom_size;
621 	unsigned long delta;
622 	unsigned int cpu;
623 	int rc;
624 
625 	/*
626 	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
627 	 * to group units.  For larger mappings, use 1M atom which
628 	 * should be large enough to contain a number of units.
629 	 */
630 	if (mmu_linear_psize == MMU_PAGE_4K)
631 		atom_size = PAGE_SIZE;
632 	else
633 		atom_size = 1 << 20;
634 
635 	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
636 				    pcpu_fc_alloc, pcpu_fc_free);
637 	if (rc < 0)
638 		panic("cannot initialize percpu area (err=%d)", rc);
639 
640 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
641 	for_each_possible_cpu(cpu)
642 		paca[cpu].data_offset = delta + pcpu_unit_offsets[cpu];
643 }
644 #endif
645 
646 
647 #ifdef CONFIG_PPC_INDIRECT_IO
648 struct ppc_pci_io ppc_pci_io;
649 EXPORT_SYMBOL(ppc_pci_io);
650 #endif /* CONFIG_PPC_INDIRECT_IO */
651 
652