xref: /linux/arch/powerpc/kernel/setup_64.c (revision a234ca0faa65dcd5cc473915bd925130ebb7b74b)
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/memblock.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/mmu_context.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 boot_cpuid = 0;
75 u64 ppc64_pft_size;
76 
77 /* Pick defaults since we might want to patch instructions
78  * before we've read this from the device tree.
79  */
80 struct ppc64_caches ppc64_caches = {
81 	.dline_size = 0x40,
82 	.log_dline_size = 6,
83 	.iline_size = 0x40,
84 	.log_iline_size = 6
85 };
86 EXPORT_SYMBOL_GPL(ppc64_caches);
87 
88 /*
89  * These are used in binfmt_elf.c to put aux entries on the stack
90  * for each elf executable being started.
91  */
92 int dcache_bsize;
93 int icache_bsize;
94 int ucache_bsize;
95 
96 #ifdef CONFIG_SMP
97 
98 static int smt_enabled_cmdline;
99 
100 /* Look for ibm,smt-enabled OF option */
101 static void check_smt_enabled(void)
102 {
103 	struct device_node *dn;
104 	const char *smt_option;
105 
106 	/* Allow the command line to overrule the OF option */
107 	if (smt_enabled_cmdline)
108 		return;
109 
110 	dn = of_find_node_by_path("/options");
111 
112 	if (dn) {
113 		smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
114 
115                 if (smt_option) {
116 			if (!strcmp(smt_option, "on"))
117 				smt_enabled_at_boot = 1;
118 			else if (!strcmp(smt_option, "off"))
119 				smt_enabled_at_boot = 0;
120                 }
121         }
122 }
123 
124 /* Look for smt-enabled= cmdline option */
125 static int __init early_smt_enabled(char *p)
126 {
127 	smt_enabled_cmdline = 1;
128 
129 	if (!p)
130 		return 0;
131 
132 	if (!strcmp(p, "on") || !strcmp(p, "1"))
133 		smt_enabled_at_boot = 1;
134 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
135 		smt_enabled_at_boot = 0;
136 
137 	return 0;
138 }
139 early_param("smt-enabled", early_smt_enabled);
140 
141 #else
142 #define check_smt_enabled()
143 #endif /* CONFIG_SMP */
144 
145 /*
146  * Early initialization entry point. This is called by head.S
147  * with MMU translation disabled. We rely on the "feature" of
148  * the CPU that ignores the top 2 bits of the address in real
149  * mode so we can access kernel globals normally provided we
150  * only toy with things in the RMO region. From here, we do
151  * some early parsing of the device-tree to setup out MEMBLOCK
152  * data structures, and allocate & initialize the hash table
153  * and segment tables so we can start running with translation
154  * enabled.
155  *
156  * It is this function which will call the probe() callback of
157  * the various platform types and copy the matching one to the
158  * global ppc_md structure. Your platform can eventually do
159  * some very early initializations from the probe() routine, but
160  * this is not recommended, be very careful as, for example, the
161  * device-tree is not accessible via normal means at this point.
162  */
163 
164 void __init early_setup(unsigned long dt_ptr)
165 {
166 	/* -------- printk is _NOT_ safe to use here ! ------- */
167 
168 	/* Identify CPU type */
169 	identify_cpu(0, mfspr(SPRN_PVR));
170 
171 	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
172 	initialise_paca(&boot_paca, 0);
173 	setup_paca(&boot_paca);
174 
175 	/* Initialize lockdep early or else spinlocks will blow */
176 	lockdep_init();
177 
178 	/* -------- printk is now safe to use ------- */
179 
180 	/* Enable early debugging if any specified (see udbg.h) */
181 	udbg_early_init();
182 
183  	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
184 
185 	/*
186 	 * Do early initialization using the flattened device
187 	 * tree, such as retrieving the physical memory map or
188 	 * calculating/retrieving the hash table size.
189 	 */
190 	early_init_devtree(__va(dt_ptr));
191 
192 	/* Now we know the logical id of our boot cpu, setup the paca. */
193 	setup_paca(&paca[boot_cpuid]);
194 
195 	/* Fix up paca fields required for the boot cpu */
196 	get_paca()->cpu_start = 1;
197 
198 	/* Probe the machine type */
199 	probe_machine();
200 
201 	setup_kdump_trampoline();
202 
203 	DBG("Found, Initializing memory management...\n");
204 
205 	/* Initialize the hash table or TLB handling */
206 	early_init_mmu();
207 
208 	DBG(" <- early_setup()\n");
209 }
210 
211 #ifdef CONFIG_SMP
212 void early_setup_secondary(void)
213 {
214 	/* Mark interrupts enabled in PACA */
215 	get_paca()->soft_enabled = 0;
216 
217 	/* Initialize the hash table or TLB handling */
218 	early_init_mmu_secondary();
219 }
220 
221 #endif /* CONFIG_SMP */
222 
223 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
224 void smp_release_cpus(void)
225 {
226 	unsigned long *ptr;
227 
228 	DBG(" -> smp_release_cpus()\n");
229 
230 	/* All secondary cpus are spinning on a common spinloop, release them
231 	 * all now so they can start to spin on their individual paca
232 	 * spinloops. For non SMP kernels, the secondary cpus never get out
233 	 * of the common spinloop.
234 	 */
235 
236 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
237 			- PHYSICAL_START);
238 	*ptr = __pa(generic_secondary_smp_init);
239 	mb();
240 
241 	DBG(" <- smp_release_cpus()\n");
242 }
243 #endif /* CONFIG_SMP || CONFIG_KEXEC */
244 
245 /*
246  * Initialize some remaining members of the ppc64_caches and systemcfg
247  * structures
248  * (at least until we get rid of them completely). This is mostly some
249  * cache informations about the CPU that will be used by cache flush
250  * routines and/or provided to userland
251  */
252 static void __init initialize_cache_info(void)
253 {
254 	struct device_node *np;
255 	unsigned long num_cpus = 0;
256 
257 	DBG(" -> initialize_cache_info()\n");
258 
259 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
260 		num_cpus += 1;
261 
262 		/* We're assuming *all* of the CPUs have the same
263 		 * d-cache and i-cache sizes... -Peter
264 		 */
265 
266 		if ( num_cpus == 1 ) {
267 			const u32 *sizep, *lsizep;
268 			u32 size, lsize;
269 
270 			size = 0;
271 			lsize = cur_cpu_spec->dcache_bsize;
272 			sizep = of_get_property(np, "d-cache-size", NULL);
273 			if (sizep != NULL)
274 				size = *sizep;
275 			lsizep = of_get_property(np, "d-cache-block-size", NULL);
276 			/* fallback if block size missing */
277 			if (lsizep == NULL)
278 				lsizep = of_get_property(np, "d-cache-line-size", NULL);
279 			if (lsizep != NULL)
280 				lsize = *lsizep;
281 			if (sizep == 0 || lsizep == 0)
282 				DBG("Argh, can't find dcache properties ! "
283 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
284 
285 			ppc64_caches.dsize = size;
286 			ppc64_caches.dline_size = lsize;
287 			ppc64_caches.log_dline_size = __ilog2(lsize);
288 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
289 
290 			size = 0;
291 			lsize = cur_cpu_spec->icache_bsize;
292 			sizep = of_get_property(np, "i-cache-size", NULL);
293 			if (sizep != NULL)
294 				size = *sizep;
295 			lsizep = of_get_property(np, "i-cache-block-size", NULL);
296 			if (lsizep == NULL)
297 				lsizep = of_get_property(np, "i-cache-line-size", NULL);
298 			if (lsizep != NULL)
299 				lsize = *lsizep;
300 			if (sizep == 0 || lsizep == 0)
301 				DBG("Argh, can't find icache properties ! "
302 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
303 
304 			ppc64_caches.isize = size;
305 			ppc64_caches.iline_size = lsize;
306 			ppc64_caches.log_iline_size = __ilog2(lsize);
307 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
308 		}
309 	}
310 
311 	DBG(" <- initialize_cache_info()\n");
312 }
313 
314 
315 /*
316  * Do some initial setup of the system.  The parameters are those which
317  * were passed in from the bootloader.
318  */
319 void __init setup_system(void)
320 {
321 	DBG(" -> setup_system()\n");
322 
323 	/* Apply the CPUs-specific and firmware specific fixups to kernel
324 	 * text (nop out sections not relevant to this CPU or this firmware)
325 	 */
326 	do_feature_fixups(cur_cpu_spec->cpu_features,
327 			  &__start___ftr_fixup, &__stop___ftr_fixup);
328 	do_feature_fixups(cur_cpu_spec->mmu_features,
329 			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
330 	do_feature_fixups(powerpc_firmware_features,
331 			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
332 	do_lwsync_fixups(cur_cpu_spec->cpu_features,
333 			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
334 
335 	/*
336 	 * Unflatten the device-tree passed by prom_init or kexec
337 	 */
338 	unflatten_device_tree();
339 
340 	/*
341 	 * Fill the ppc64_caches & systemcfg structures with informations
342  	 * retrieved from the device-tree.
343 	 */
344 	initialize_cache_info();
345 
346 #ifdef CONFIG_PPC_RTAS
347 	/*
348 	 * Initialize RTAS if available
349 	 */
350 	rtas_initialize();
351 #endif /* CONFIG_PPC_RTAS */
352 
353 	/*
354 	 * Check if we have an initrd provided via the device-tree
355 	 */
356 	check_for_initrd();
357 
358 	/*
359 	 * Do some platform specific early initializations, that includes
360 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
361 	 * related options that will be used by finish_device_tree()
362 	 */
363 	if (ppc_md.init_early)
364 		ppc_md.init_early();
365 
366  	/*
367 	 * We can discover serial ports now since the above did setup the
368 	 * hash table management for us, thus ioremap works. We do that early
369 	 * so that further code can be debugged
370 	 */
371 	find_legacy_serial_ports();
372 
373 	/*
374 	 * Register early console
375 	 */
376 	register_early_udbg_console();
377 
378 	/*
379 	 * Initialize xmon
380 	 */
381 	xmon_setup();
382 
383 	check_smt_enabled();
384 	smp_setup_cpu_maps();
385 
386 #ifdef CONFIG_SMP
387 	/* Release secondary cpus out of their spinloops at 0x60 now that
388 	 * we can map physical -> logical CPU ids
389 	 */
390 	smp_release_cpus();
391 #endif
392 
393 	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
394 
395 	printk("-----------------------------------------------------\n");
396 	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
397 	printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
398 	if (ppc64_caches.dline_size != 0x80)
399 		printk("ppc64_caches.dcache_line_size = 0x%x\n",
400 		       ppc64_caches.dline_size);
401 	if (ppc64_caches.iline_size != 0x80)
402 		printk("ppc64_caches.icache_line_size = 0x%x\n",
403 		       ppc64_caches.iline_size);
404 #ifdef CONFIG_PPC_STD_MMU_64
405 	if (htab_address)
406 		printk("htab_address                  = 0x%p\n", htab_address);
407 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
408 #endif /* CONFIG_PPC_STD_MMU_64 */
409 	if (PHYSICAL_START > 0)
410 		printk("physical_start                = 0x%llx\n",
411 		       (unsigned long long)PHYSICAL_START);
412 	printk("-----------------------------------------------------\n");
413 
414 	DBG(" <- setup_system()\n");
415 }
416 
417 static u64 slb0_limit(void)
418 {
419 	if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) {
420 		return 1UL << SID_SHIFT_1T;
421 	}
422 	return 1UL << SID_SHIFT;
423 }
424 
425 static void __init irqstack_early_init(void)
426 {
427 	u64 limit = slb0_limit();
428 	unsigned int i;
429 
430 	/*
431 	 * interrupt stacks must be under 256MB, we cannot afford to take
432 	 * SLB misses on them.
433 	 */
434 	for_each_possible_cpu(i) {
435 		softirq_ctx[i] = (struct thread_info *)
436 			__va(memblock_alloc_base(THREAD_SIZE,
437 					    THREAD_SIZE, limit));
438 		hardirq_ctx[i] = (struct thread_info *)
439 			__va(memblock_alloc_base(THREAD_SIZE,
440 					    THREAD_SIZE, limit));
441 	}
442 }
443 
444 #ifdef CONFIG_PPC_BOOK3E
445 static void __init exc_lvl_early_init(void)
446 {
447 	unsigned int i;
448 
449 	for_each_possible_cpu(i) {
450 		critirq_ctx[i] = (struct thread_info *)
451 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
452 		dbgirq_ctx[i] = (struct thread_info *)
453 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
454 		mcheckirq_ctx[i] = (struct thread_info *)
455 			__va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
456 	}
457 }
458 #else
459 #define exc_lvl_early_init()
460 #endif
461 
462 /*
463  * Stack space used when we detect a bad kernel stack pointer, and
464  * early in SMP boots before relocation is enabled.
465  */
466 static void __init emergency_stack_init(void)
467 {
468 	u64 limit;
469 	unsigned int i;
470 
471 	/*
472 	 * Emergency stacks must be under 256MB, we cannot afford to take
473 	 * SLB misses on them. The ABI also requires them to be 128-byte
474 	 * aligned.
475 	 *
476 	 * Since we use these as temporary stacks during secondary CPU
477 	 * bringup, we need to get at them in real mode. This means they
478 	 * must also be within the RMO region.
479 	 */
480 	limit = min(slb0_limit(), memblock.rmo_size);
481 
482 	for_each_possible_cpu(i) {
483 		unsigned long sp;
484 		sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
485 		sp += THREAD_SIZE;
486 		paca[i].emergency_sp = __va(sp);
487 	}
488 }
489 
490 /*
491  * Called into from start_kernel, after lock_kernel has been called.
492  * Initializes bootmem, which is unsed to manage page allocation until
493  * mem_init is called.
494  */
495 void __init setup_arch(char **cmdline_p)
496 {
497 	ppc64_boot_msg(0x12, "Setup Arch");
498 
499 	*cmdline_p = cmd_line;
500 
501 	/*
502 	 * Set cache line size based on type of cpu as a default.
503 	 * Systems with OF can look in the properties on the cpu node(s)
504 	 * for a possibly more accurate value.
505 	 */
506 	dcache_bsize = ppc64_caches.dline_size;
507 	icache_bsize = ppc64_caches.iline_size;
508 
509 	/* reboot on panic */
510 	panic_timeout = 180;
511 
512 	if (ppc_md.panic)
513 		setup_panic();
514 
515 	init_mm.start_code = (unsigned long)_stext;
516 	init_mm.end_code = (unsigned long) _etext;
517 	init_mm.end_data = (unsigned long) _edata;
518 	init_mm.brk = klimit;
519 
520 	irqstack_early_init();
521 	exc_lvl_early_init();
522 	emergency_stack_init();
523 
524 #ifdef CONFIG_PPC_STD_MMU_64
525 	stabs_alloc();
526 #endif
527 	/* set up the bootmem stuff with available memory */
528 	do_init_bootmem();
529 	sparse_init();
530 
531 #ifdef CONFIG_DUMMY_CONSOLE
532 	conswitchp = &dummy_con;
533 #endif
534 
535 	if (ppc_md.setup_arch)
536 		ppc_md.setup_arch();
537 
538 	paging_init();
539 
540 	/* Initialize the MMU context management stuff */
541 	mmu_context_init();
542 
543 	ppc64_boot_msg(0x15, "Setup Done");
544 }
545 
546 
547 /* ToDo: do something useful if ppc_md is not yet setup. */
548 #define PPC64_LINUX_FUNCTION 0x0f000000
549 #define PPC64_IPL_MESSAGE 0xc0000000
550 #define PPC64_TERM_MESSAGE 0xb0000000
551 
552 static void ppc64_do_msg(unsigned int src, const char *msg)
553 {
554 	if (ppc_md.progress) {
555 		char buf[128];
556 
557 		sprintf(buf, "%08X\n", src);
558 		ppc_md.progress(buf, 0);
559 		snprintf(buf, 128, "%s", msg);
560 		ppc_md.progress(buf, 0);
561 	}
562 }
563 
564 /* Print a boot progress message. */
565 void ppc64_boot_msg(unsigned int src, const char *msg)
566 {
567 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
568 	printk("[boot]%04x %s\n", src, msg);
569 }
570 
571 #ifdef CONFIG_SMP
572 #define PCPU_DYN_SIZE		()
573 
574 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
575 {
576 	return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
577 				    __pa(MAX_DMA_ADDRESS));
578 }
579 
580 static void __init pcpu_fc_free(void *ptr, size_t size)
581 {
582 	free_bootmem(__pa(ptr), size);
583 }
584 
585 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
586 {
587 	if (cpu_to_node(from) == cpu_to_node(to))
588 		return LOCAL_DISTANCE;
589 	else
590 		return REMOTE_DISTANCE;
591 }
592 
593 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
594 EXPORT_SYMBOL(__per_cpu_offset);
595 
596 void __init setup_per_cpu_areas(void)
597 {
598 	const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
599 	size_t atom_size;
600 	unsigned long delta;
601 	unsigned int cpu;
602 	int rc;
603 
604 	/*
605 	 * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
606 	 * to group units.  For larger mappings, use 1M atom which
607 	 * should be large enough to contain a number of units.
608 	 */
609 	if (mmu_linear_psize == MMU_PAGE_4K)
610 		atom_size = PAGE_SIZE;
611 	else
612 		atom_size = 1 << 20;
613 
614 	rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
615 				    pcpu_fc_alloc, pcpu_fc_free);
616 	if (rc < 0)
617 		panic("cannot initialize percpu area (err=%d)", rc);
618 
619 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
620 	for_each_possible_cpu(cpu) {
621                 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
622 		paca[cpu].data_offset = __per_cpu_offset[cpu];
623 	}
624 }
625 #endif
626 
627 
628 #ifdef CONFIG_PPC_INDIRECT_IO
629 struct ppc_pci_io ppc_pci_io;
630 EXPORT_SYMBOL(ppc_pci_io);
631 #endif /* CONFIG_PPC_INDIRECT_IO */
632 
633