xref: /openbmc/linux/arch/powerpc/kernel/setup_64.c (revision 82ced6fd)
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 
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 int boot_cpuid = 0;
74 u64 ppc64_pft_size;
75 
76 /* Pick defaults since we might want to patch instructions
77  * before we've read this from the device tree.
78  */
79 struct ppc64_caches ppc64_caches = {
80 	.dline_size = 0x40,
81 	.log_dline_size = 6,
82 	.iline_size = 0x40,
83 	.log_iline_size = 6
84 };
85 EXPORT_SYMBOL_GPL(ppc64_caches);
86 
87 /*
88  * These are used in binfmt_elf.c to put aux entries on the stack
89  * for each elf executable being started.
90  */
91 int dcache_bsize;
92 int icache_bsize;
93 int ucache_bsize;
94 
95 #ifdef CONFIG_SMP
96 
97 static int smt_enabled_cmdline;
98 
99 /* Look for ibm,smt-enabled OF option */
100 static void check_smt_enabled(void)
101 {
102 	struct device_node *dn;
103 	const char *smt_option;
104 
105 	/* Allow the command line to overrule the OF option */
106 	if (smt_enabled_cmdline)
107 		return;
108 
109 	dn = of_find_node_by_path("/options");
110 
111 	if (dn) {
112 		smt_option = of_get_property(dn, "ibm,smt-enabled", NULL);
113 
114                 if (smt_option) {
115 			if (!strcmp(smt_option, "on"))
116 				smt_enabled_at_boot = 1;
117 			else if (!strcmp(smt_option, "off"))
118 				smt_enabled_at_boot = 0;
119                 }
120         }
121 }
122 
123 /* Look for smt-enabled= cmdline option */
124 static int __init early_smt_enabled(char *p)
125 {
126 	smt_enabled_cmdline = 1;
127 
128 	if (!p)
129 		return 0;
130 
131 	if (!strcmp(p, "on") || !strcmp(p, "1"))
132 		smt_enabled_at_boot = 1;
133 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
134 		smt_enabled_at_boot = 0;
135 
136 	return 0;
137 }
138 early_param("smt-enabled", early_smt_enabled);
139 
140 #else
141 #define check_smt_enabled()
142 #endif /* CONFIG_SMP */
143 
144 /* Put the paca pointer into r13 and SPRG3 */
145 void __init setup_paca(int cpu)
146 {
147 	local_paca = &paca[cpu];
148 	mtspr(SPRN_SPRG3, local_paca);
149 }
150 
151 /*
152  * Early initialization entry point. This is called by head.S
153  * with MMU translation disabled. We rely on the "feature" of
154  * the CPU that ignores the top 2 bits of the address in real
155  * mode so we can access kernel globals normally provided we
156  * only toy with things in the RMO region. From here, we do
157  * some early parsing of the device-tree to setup out LMB
158  * data structures, and allocate & initialize the hash table
159  * and segment tables so we can start running with translation
160  * enabled.
161  *
162  * It is this function which will call the probe() callback of
163  * the various platform types and copy the matching one to the
164  * global ppc_md structure. Your platform can eventually do
165  * some very early initializations from the probe() routine, but
166  * this is not recommended, be very careful as, for example, the
167  * device-tree is not accessible via normal means at this point.
168  */
169 
170 void __init early_setup(unsigned long dt_ptr)
171 {
172 	/* -------- printk is _NOT_ safe to use here ! ------- */
173 
174 	/* Fill in any unititialised pacas */
175 	initialise_pacas();
176 
177 	/* Identify CPU type */
178 	identify_cpu(0, mfspr(SPRN_PVR));
179 
180 	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
181 	setup_paca(0);
182 
183 	/* Initialize lockdep early or else spinlocks will blow */
184 	lockdep_init();
185 
186 	/* -------- printk is now safe to use ------- */
187 
188 	/* Enable early debugging if any specified (see udbg.h) */
189 	udbg_early_init();
190 
191  	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
192 
193 	/*
194 	 * Do early initialization using the flattened device
195 	 * tree, such as retrieving the physical memory map or
196 	 * calculating/retrieving the hash table size.
197 	 */
198 	early_init_devtree(__va(dt_ptr));
199 
200 	/* Now we know the logical id of our boot cpu, setup the paca. */
201 	setup_paca(boot_cpuid);
202 
203 	/* Fix up paca fields required for the boot cpu */
204 	get_paca()->cpu_start = 1;
205 
206 	/* Probe the machine type */
207 	probe_machine();
208 
209 	setup_kdump_trampoline();
210 
211 	DBG("Found, Initializing memory management...\n");
212 
213 	/* Initialize the hash table or TLB handling */
214 	early_init_mmu();
215 
216 	DBG(" <- early_setup()\n");
217 }
218 
219 #ifdef CONFIG_SMP
220 void early_setup_secondary(void)
221 {
222 	/* Mark interrupts enabled in PACA */
223 	get_paca()->soft_enabled = 0;
224 
225 	/* Initialize the hash table or TLB handling */
226 	early_init_mmu_secondary();
227 }
228 
229 #endif /* CONFIG_SMP */
230 
231 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
232 extern unsigned long __secondary_hold_spinloop;
233 extern void generic_secondary_smp_init(void);
234 
235 void smp_release_cpus(void)
236 {
237 	unsigned long *ptr;
238 
239 	DBG(" -> smp_release_cpus()\n");
240 
241 	/* All secondary cpus are spinning on a common spinloop, release them
242 	 * all now so they can start to spin on their individual paca
243 	 * spinloops. For non SMP kernels, the secondary cpus never get out
244 	 * of the common spinloop.
245 	 */
246 
247 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
248 			- PHYSICAL_START);
249 	*ptr = __pa(generic_secondary_smp_init);
250 	mb();
251 
252 	DBG(" <- smp_release_cpus()\n");
253 }
254 #endif /* CONFIG_SMP || CONFIG_KEXEC */
255 
256 /*
257  * Initialize some remaining members of the ppc64_caches and systemcfg
258  * structures
259  * (at least until we get rid of them completely). This is mostly some
260  * cache informations about the CPU that will be used by cache flush
261  * routines and/or provided to userland
262  */
263 static void __init initialize_cache_info(void)
264 {
265 	struct device_node *np;
266 	unsigned long num_cpus = 0;
267 
268 	DBG(" -> initialize_cache_info()\n");
269 
270 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
271 		num_cpus += 1;
272 
273 		/* We're assuming *all* of the CPUs have the same
274 		 * d-cache and i-cache sizes... -Peter
275 		 */
276 
277 		if ( num_cpus == 1 ) {
278 			const u32 *sizep, *lsizep;
279 			u32 size, lsize;
280 
281 			size = 0;
282 			lsize = cur_cpu_spec->dcache_bsize;
283 			sizep = of_get_property(np, "d-cache-size", NULL);
284 			if (sizep != NULL)
285 				size = *sizep;
286 			lsizep = of_get_property(np, "d-cache-block-size", NULL);
287 			/* fallback if block size missing */
288 			if (lsizep == NULL)
289 				lsizep = of_get_property(np, "d-cache-line-size", NULL);
290 			if (lsizep != NULL)
291 				lsize = *lsizep;
292 			if (sizep == 0 || lsizep == 0)
293 				DBG("Argh, can't find dcache properties ! "
294 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
295 
296 			ppc64_caches.dsize = size;
297 			ppc64_caches.dline_size = lsize;
298 			ppc64_caches.log_dline_size = __ilog2(lsize);
299 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
300 
301 			size = 0;
302 			lsize = cur_cpu_spec->icache_bsize;
303 			sizep = of_get_property(np, "i-cache-size", NULL);
304 			if (sizep != NULL)
305 				size = *sizep;
306 			lsizep = of_get_property(np, "i-cache-block-size", NULL);
307 			if (lsizep == NULL)
308 				lsizep = of_get_property(np, "i-cache-line-size", NULL);
309 			if (lsizep != NULL)
310 				lsize = *lsizep;
311 			if (sizep == 0 || lsizep == 0)
312 				DBG("Argh, can't find icache properties ! "
313 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
314 
315 			ppc64_caches.isize = size;
316 			ppc64_caches.iline_size = lsize;
317 			ppc64_caches.log_iline_size = __ilog2(lsize);
318 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
319 		}
320 	}
321 
322 	DBG(" <- initialize_cache_info()\n");
323 }
324 
325 
326 /*
327  * Do some initial setup of the system.  The parameters are those which
328  * were passed in from the bootloader.
329  */
330 void __init setup_system(void)
331 {
332 	DBG(" -> setup_system()\n");
333 
334 	/* Apply the CPUs-specific and firmware specific fixups to kernel
335 	 * text (nop out sections not relevant to this CPU or this firmware)
336 	 */
337 	do_feature_fixups(cur_cpu_spec->cpu_features,
338 			  &__start___ftr_fixup, &__stop___ftr_fixup);
339 	do_feature_fixups(cur_cpu_spec->mmu_features,
340 			  &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
341 	do_feature_fixups(powerpc_firmware_features,
342 			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
343 	do_lwsync_fixups(cur_cpu_spec->cpu_features,
344 			 &__start___lwsync_fixup, &__stop___lwsync_fixup);
345 
346 	/*
347 	 * Unflatten the device-tree passed by prom_init or kexec
348 	 */
349 	unflatten_device_tree();
350 
351 	/*
352 	 * Fill the ppc64_caches & systemcfg structures with informations
353  	 * retrieved from the device-tree.
354 	 */
355 	initialize_cache_info();
356 
357 	/*
358 	 * Initialize irq remapping subsystem
359 	 */
360 	irq_early_init();
361 
362 #ifdef CONFIG_PPC_RTAS
363 	/*
364 	 * Initialize RTAS if available
365 	 */
366 	rtas_initialize();
367 #endif /* CONFIG_PPC_RTAS */
368 
369 	/*
370 	 * Check if we have an initrd provided via the device-tree
371 	 */
372 	check_for_initrd();
373 
374 	/*
375 	 * Do some platform specific early initializations, that includes
376 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
377 	 * related options that will be used by finish_device_tree()
378 	 */
379 	if (ppc_md.init_early)
380 		ppc_md.init_early();
381 
382  	/*
383 	 * We can discover serial ports now since the above did setup the
384 	 * hash table management for us, thus ioremap works. We do that early
385 	 * so that further code can be debugged
386 	 */
387 	find_legacy_serial_ports();
388 
389 	/*
390 	 * Register early console
391 	 */
392 	register_early_udbg_console();
393 
394 	/*
395 	 * Initialize xmon
396 	 */
397 	xmon_setup();
398 
399 	check_smt_enabled();
400 	smp_setup_cpu_maps();
401 
402 #ifdef CONFIG_SMP
403 	/* Release secondary cpus out of their spinloops at 0x60 now that
404 	 * we can map physical -> logical CPU ids
405 	 */
406 	smp_release_cpus();
407 #endif
408 
409 	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
410 
411 	printk("-----------------------------------------------------\n");
412 	printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
413 	printk("physicalMemorySize            = 0x%llx\n", lmb_phys_mem_size());
414 	if (ppc64_caches.dline_size != 0x80)
415 		printk("ppc64_caches.dcache_line_size = 0x%x\n",
416 		       ppc64_caches.dline_size);
417 	if (ppc64_caches.iline_size != 0x80)
418 		printk("ppc64_caches.icache_line_size = 0x%x\n",
419 		       ppc64_caches.iline_size);
420 	if (htab_address)
421 		printk("htab_address                  = 0x%p\n", htab_address);
422 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
423 	if (PHYSICAL_START > 0)
424 		printk("physical_start                = 0x%lx\n",
425 		       PHYSICAL_START);
426 	printk("-----------------------------------------------------\n");
427 
428 	DBG(" <- setup_system()\n");
429 }
430 
431 #ifdef CONFIG_IRQSTACKS
432 static void __init irqstack_early_init(void)
433 {
434 	unsigned int i;
435 
436 	/*
437 	 * interrupt stacks must be under 256MB, we cannot afford to take
438 	 * SLB misses on them.
439 	 */
440 	for_each_possible_cpu(i) {
441 		softirq_ctx[i] = (struct thread_info *)
442 			__va(lmb_alloc_base(THREAD_SIZE,
443 					    THREAD_SIZE, 0x10000000));
444 		hardirq_ctx[i] = (struct thread_info *)
445 			__va(lmb_alloc_base(THREAD_SIZE,
446 					    THREAD_SIZE, 0x10000000));
447 	}
448 }
449 #else
450 #define irqstack_early_init()
451 #endif
452 
453 /*
454  * Stack space used when we detect a bad kernel stack pointer, and
455  * early in SMP boots before relocation is enabled.
456  */
457 static void __init emergency_stack_init(void)
458 {
459 	unsigned long limit;
460 	unsigned int i;
461 
462 	/*
463 	 * Emergency stacks must be under 256MB, we cannot afford to take
464 	 * SLB misses on them. The ABI also requires them to be 128-byte
465 	 * aligned.
466 	 *
467 	 * Since we use these as temporary stacks during secondary CPU
468 	 * bringup, we need to get at them in real mode. This means they
469 	 * must also be within the RMO region.
470 	 */
471 	limit = min(0x10000000ULL, lmb.rmo_size);
472 
473 	for_each_possible_cpu(i) {
474 		unsigned long sp;
475 		sp  = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
476 		sp += THREAD_SIZE;
477 		paca[i].emergency_sp = __va(sp);
478 	}
479 }
480 
481 /*
482  * Called into from start_kernel, after lock_kernel has been called.
483  * Initializes bootmem, which is unsed to manage page allocation until
484  * mem_init is called.
485  */
486 void __init setup_arch(char **cmdline_p)
487 {
488 	ppc64_boot_msg(0x12, "Setup Arch");
489 
490 	*cmdline_p = cmd_line;
491 
492 	/*
493 	 * Set cache line size based on type of cpu as a default.
494 	 * Systems with OF can look in the properties on the cpu node(s)
495 	 * for a possibly more accurate value.
496 	 */
497 	dcache_bsize = ppc64_caches.dline_size;
498 	icache_bsize = ppc64_caches.iline_size;
499 
500 	/* reboot on panic */
501 	panic_timeout = 180;
502 
503 	if (ppc_md.panic)
504 		setup_panic();
505 
506 	init_mm.start_code = (unsigned long)_stext;
507 	init_mm.end_code = (unsigned long) _etext;
508 	init_mm.end_data = (unsigned long) _edata;
509 	init_mm.brk = klimit;
510 
511 	irqstack_early_init();
512 	emergency_stack_init();
513 
514 	stabs_alloc();
515 
516 	/* set up the bootmem stuff with available memory */
517 	do_init_bootmem();
518 	sparse_init();
519 
520 #ifdef CONFIG_DUMMY_CONSOLE
521 	conswitchp = &dummy_con;
522 #endif
523 
524 	if (ppc_md.setup_arch)
525 		ppc_md.setup_arch();
526 
527 	paging_init();
528 	ppc64_boot_msg(0x15, "Setup Done");
529 }
530 
531 
532 /* ToDo: do something useful if ppc_md is not yet setup. */
533 #define PPC64_LINUX_FUNCTION 0x0f000000
534 #define PPC64_IPL_MESSAGE 0xc0000000
535 #define PPC64_TERM_MESSAGE 0xb0000000
536 
537 static void ppc64_do_msg(unsigned int src, const char *msg)
538 {
539 	if (ppc_md.progress) {
540 		char buf[128];
541 
542 		sprintf(buf, "%08X\n", src);
543 		ppc_md.progress(buf, 0);
544 		snprintf(buf, 128, "%s", msg);
545 		ppc_md.progress(buf, 0);
546 	}
547 }
548 
549 /* Print a boot progress message. */
550 void ppc64_boot_msg(unsigned int src, const char *msg)
551 {
552 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
553 	printk("[boot]%04x %s\n", src, msg);
554 }
555 
556 void cpu_die(void)
557 {
558 	if (ppc_md.cpu_die)
559 		ppc_md.cpu_die();
560 }
561 
562 #ifdef CONFIG_SMP
563 void __init setup_per_cpu_areas(void)
564 {
565 	int i;
566 	unsigned long size;
567 	char *ptr;
568 
569 	/* Copy section for each CPU (we discard the original) */
570 	size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
571 #ifdef CONFIG_MODULES
572 	if (size < PERCPU_ENOUGH_ROOM)
573 		size = PERCPU_ENOUGH_ROOM;
574 #endif
575 
576 	for_each_possible_cpu(i) {
577 		ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
578 
579 		paca[i].data_offset = ptr - __per_cpu_start;
580 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
581 	}
582 }
583 #endif
584 
585 
586 #ifdef CONFIG_PPC_INDIRECT_IO
587 struct ppc_pci_io ppc_pci_io;
588 EXPORT_SYMBOL(ppc_pci_io);
589 #endif /* CONFIG_PPC_INDIRECT_IO */
590 
591