xref: /linux/arch/powerpc/kernel/setup_64.c (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
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/ide.h>
24 #include <linux/seq_file.h>
25 #include <linux/ioport.h>
26 #include <linux/console.h>
27 #include <linux/utsname.h>
28 #include <linux/tty.h>
29 #include <linux/root_dev.h>
30 #include <linux/notifier.h>
31 #include <linux/cpu.h>
32 #include <linux/unistd.h>
33 #include <linux/serial.h>
34 #include <linux/serial_8250.h>
35 #include <linux/bootmem.h>
36 #include <linux/pci.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/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 have_of = 1;
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 = 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 /* Put the paca pointer into r13 and SPRG3 */
146 void __init setup_paca(int cpu)
147 {
148 	local_paca = &paca[cpu];
149 	mtspr(SPRN_SPRG3, local_paca);
150 }
151 
152 /*
153  * Early initialization entry point. This is called by head.S
154  * with MMU translation disabled. We rely on the "feature" of
155  * the CPU that ignores the top 2 bits of the address in real
156  * mode so we can access kernel globals normally provided we
157  * only toy with things in the RMO region. From here, we do
158  * some early parsing of the device-tree to setup out LMB
159  * data structures, and allocate & initialize the hash table
160  * and segment tables so we can start running with translation
161  * enabled.
162  *
163  * It is this function which will call the probe() callback of
164  * the various platform types and copy the matching one to the
165  * global ppc_md structure. Your platform can eventually do
166  * some very early initializations from the probe() routine, but
167  * this is not recommended, be very careful as, for example, the
168  * device-tree is not accessible via normal means at this point.
169  */
170 
171 void __init early_setup(unsigned long dt_ptr)
172 {
173 	/* Identify CPU type */
174 	identify_cpu(0, mfspr(SPRN_PVR));
175 
176 	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
177 	setup_paca(0);
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_paca(boot_cpuid);
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 	setup_kdump_trampoline();
203 
204 	DBG("Found, Initializing memory management...\n");
205 
206 	/*
207 	 * Initialize the MMU Hash table and create the linear mapping
208 	 * of memory. Has to be done before stab/slb initialization as
209 	 * this is currently where the page size encoding is obtained
210 	 */
211 	htab_initialize();
212 
213 	/*
214 	 * Initialize stab / SLB management except on iSeries
215 	 */
216 	if (cpu_has_feature(CPU_FTR_SLB))
217 		slb_initialize();
218 	else if (!firmware_has_feature(FW_FEATURE_ISERIES))
219 		stab_initialize(get_paca()->stab_real);
220 
221 	DBG(" <- early_setup()\n");
222 }
223 
224 #ifdef CONFIG_SMP
225 void early_setup_secondary(void)
226 {
227 	struct paca_struct *lpaca = get_paca();
228 
229 	/* Mark interrupts enabled in PACA */
230 	lpaca->soft_enabled = 0;
231 
232 	/* Initialize hash table for that CPU */
233 	htab_initialize_secondary();
234 
235 	/* Initialize STAB/SLB. We use a virtual address as it works
236 	 * in real mode on pSeries and we want a virutal address on
237 	 * iSeries anyway
238 	 */
239 	if (cpu_has_feature(CPU_FTR_SLB))
240 		slb_initialize();
241 	else
242 		stab_initialize(lpaca->stab_addr);
243 }
244 
245 #endif /* CONFIG_SMP */
246 
247 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
248 void smp_release_cpus(void)
249 {
250 	extern unsigned long __secondary_hold_spinloop;
251 	unsigned long *ptr;
252 
253 	DBG(" -> smp_release_cpus()\n");
254 
255 	/* All secondary cpus are spinning on a common spinloop, release them
256 	 * all now so they can start to spin on their individual paca
257 	 * spinloops. For non SMP kernels, the secondary cpus never get out
258 	 * of the common spinloop.
259 	 * This is useless but harmless on iSeries, secondaries are already
260 	 * waiting on their paca spinloops. */
261 
262 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
263 			- PHYSICAL_START);
264 	*ptr = 1;
265 	mb();
266 
267 	DBG(" <- smp_release_cpus()\n");
268 }
269 #endif /* CONFIG_SMP || CONFIG_KEXEC */
270 
271 /*
272  * Initialize some remaining members of the ppc64_caches and systemcfg
273  * structures
274  * (at least until we get rid of them completely). This is mostly some
275  * cache informations about the CPU that will be used by cache flush
276  * routines and/or provided to userland
277  */
278 static void __init initialize_cache_info(void)
279 {
280 	struct device_node *np;
281 	unsigned long num_cpus = 0;
282 
283 	DBG(" -> initialize_cache_info()\n");
284 
285 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
286 		num_cpus += 1;
287 
288 		/* We're assuming *all* of the CPUs have the same
289 		 * d-cache and i-cache sizes... -Peter
290 		 */
291 
292 		if ( num_cpus == 1 ) {
293 			const u32 *sizep, *lsizep;
294 			u32 size, lsize;
295 			const char *dc, *ic;
296 
297 			/* Then read cache informations */
298 			if (machine_is(powermac)) {
299 				dc = "d-cache-block-size";
300 				ic = "i-cache-block-size";
301 			} else {
302 				dc = "d-cache-line-size";
303 				ic = "i-cache-line-size";
304 			}
305 
306 			size = 0;
307 			lsize = cur_cpu_spec->dcache_bsize;
308 			sizep = get_property(np, "d-cache-size", NULL);
309 			if (sizep != NULL)
310 				size = *sizep;
311 			lsizep = get_property(np, dc, NULL);
312 			if (lsizep != NULL)
313 				lsize = *lsizep;
314 			if (sizep == 0 || lsizep == 0)
315 				DBG("Argh, can't find dcache properties ! "
316 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
317 
318 			ppc64_caches.dsize = size;
319 			ppc64_caches.dline_size = lsize;
320 			ppc64_caches.log_dline_size = __ilog2(lsize);
321 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
322 
323 			size = 0;
324 			lsize = cur_cpu_spec->icache_bsize;
325 			sizep = get_property(np, "i-cache-size", NULL);
326 			if (sizep != NULL)
327 				size = *sizep;
328 			lsizep = get_property(np, ic, NULL);
329 			if (lsizep != NULL)
330 				lsize = *lsizep;
331 			if (sizep == 0 || lsizep == 0)
332 				DBG("Argh, can't find icache properties ! "
333 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
334 
335 			ppc64_caches.isize = size;
336 			ppc64_caches.iline_size = lsize;
337 			ppc64_caches.log_iline_size = __ilog2(lsize);
338 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
339 		}
340 	}
341 
342 	DBG(" <- initialize_cache_info()\n");
343 }
344 
345 
346 /*
347  * Do some initial setup of the system.  The parameters are those which
348  * were passed in from the bootloader.
349  */
350 void __init setup_system(void)
351 {
352 	DBG(" -> setup_system()\n");
353 
354 	/* Apply the CPUs-specific and firmware specific fixups to kernel
355 	 * text (nop out sections not relevant to this CPU or this firmware)
356 	 */
357 	do_feature_fixups(cur_cpu_spec->cpu_features,
358 			  &__start___ftr_fixup, &__stop___ftr_fixup);
359 	do_feature_fixups(powerpc_firmware_features,
360 			  &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
361 
362 	/*
363 	 * Unflatten the device-tree passed by prom_init or kexec
364 	 */
365 	unflatten_device_tree();
366 
367 	/*
368 	 * Fill the ppc64_caches & systemcfg structures with informations
369  	 * retrieved from the device-tree.
370 	 */
371 	initialize_cache_info();
372 
373 	/*
374 	 * Initialize irq remapping subsystem
375 	 */
376 	irq_early_init();
377 
378 #ifdef CONFIG_PPC_RTAS
379 	/*
380 	 * Initialize RTAS if available
381 	 */
382 	rtas_initialize();
383 #endif /* CONFIG_PPC_RTAS */
384 
385 	/*
386 	 * Check if we have an initrd provided via the device-tree
387 	 */
388 	check_for_initrd();
389 
390 	/*
391 	 * Do some platform specific early initializations, that includes
392 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
393 	 * related options that will be used by finish_device_tree()
394 	 */
395 	if (ppc_md.init_early)
396 		ppc_md.init_early();
397 
398  	/*
399 	 * We can discover serial ports now since the above did setup the
400 	 * hash table management for us, thus ioremap works. We do that early
401 	 * so that further code can be debugged
402 	 */
403 	find_legacy_serial_ports();
404 
405 	/*
406 	 * Register early console
407 	 */
408 	register_early_udbg_console();
409 
410 	/*
411 	 * Initialize xmon
412 	 */
413 	xmon_setup();
414 
415 	check_smt_enabled();
416 	smp_setup_cpu_maps();
417 
418 #ifdef CONFIG_SMP
419 	/* Release secondary cpus out of their spinloops at 0x60 now that
420 	 * we can map physical -> logical CPU ids
421 	 */
422 	smp_release_cpus();
423 #endif
424 
425 	printk("Starting Linux PPC64 %s\n", init_utsname()->version);
426 
427 	printk("-----------------------------------------------------\n");
428 	printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
429 	printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
430 	printk("ppc64_caches.dcache_line_size = 0x%x\n",
431 	       ppc64_caches.dline_size);
432 	printk("ppc64_caches.icache_line_size = 0x%x\n",
433 	       ppc64_caches.iline_size);
434 	printk("htab_address                  = 0x%p\n", htab_address);
435 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
436 #if PHYSICAL_START > 0
437 	printk("physical_start                = 0x%x\n", PHYSICAL_START);
438 #endif
439 	printk("-----------------------------------------------------\n");
440 
441 	DBG(" <- setup_system()\n");
442 }
443 
444 #ifdef CONFIG_IRQSTACKS
445 static void __init irqstack_early_init(void)
446 {
447 	unsigned int i;
448 
449 	/*
450 	 * interrupt stacks must be under 256MB, we cannot afford to take
451 	 * SLB misses on them.
452 	 */
453 	for_each_possible_cpu(i) {
454 		softirq_ctx[i] = (struct thread_info *)
455 			__va(lmb_alloc_base(THREAD_SIZE,
456 					    THREAD_SIZE, 0x10000000));
457 		hardirq_ctx[i] = (struct thread_info *)
458 			__va(lmb_alloc_base(THREAD_SIZE,
459 					    THREAD_SIZE, 0x10000000));
460 	}
461 }
462 #else
463 #define irqstack_early_init()
464 #endif
465 
466 /*
467  * Stack space used when we detect a bad kernel stack pointer, and
468  * early in SMP boots before relocation is enabled.
469  */
470 static void __init emergency_stack_init(void)
471 {
472 	unsigned long limit;
473 	unsigned int i;
474 
475 	/*
476 	 * Emergency stacks must be under 256MB, we cannot afford to take
477 	 * SLB misses on them. The ABI also requires them to be 128-byte
478 	 * aligned.
479 	 *
480 	 * Since we use these as temporary stacks during secondary CPU
481 	 * bringup, we need to get at them in real mode. This means they
482 	 * must also be within the RMO region.
483 	 */
484 	limit = min(0x10000000UL, lmb.rmo_size);
485 
486 	for_each_possible_cpu(i)
487 		paca[i].emergency_sp =
488 		__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
489 }
490 
491 /*
492  * Called into from start_kernel, after lock_kernel has been called.
493  * Initializes bootmem, which is unsed to manage page allocation until
494  * mem_init is called.
495  */
496 void __init setup_arch(char **cmdline_p)
497 {
498 	ppc64_boot_msg(0x12, "Setup Arch");
499 
500 	*cmdline_p = cmd_line;
501 
502 	/*
503 	 * Set cache line size based on type of cpu as a default.
504 	 * Systems with OF can look in the properties on the cpu node(s)
505 	 * for a possibly more accurate value.
506 	 */
507 	dcache_bsize = ppc64_caches.dline_size;
508 	icache_bsize = ppc64_caches.iline_size;
509 
510 	/* reboot on panic */
511 	panic_timeout = 180;
512 
513 	if (ppc_md.panic)
514 		setup_panic();
515 
516 	init_mm.start_code = PAGE_OFFSET;
517 	init_mm.end_code = (unsigned long) _etext;
518 	init_mm.end_data = (unsigned long) _edata;
519 	init_mm.brk = klimit;
520 
521 	irqstack_early_init();
522 	emergency_stack_init();
523 
524 	stabs_alloc();
525 
526 	/* set up the bootmem stuff with available memory */
527 	do_init_bootmem();
528 	sparse_init();
529 
530 #ifdef CONFIG_DUMMY_CONSOLE
531 	conswitchp = &dummy_con;
532 #endif
533 
534 	ppc_md.setup_arch();
535 
536 	paging_init();
537 	ppc64_boot_msg(0x15, "Setup Done");
538 }
539 
540 
541 /* ToDo: do something useful if ppc_md is not yet setup. */
542 #define PPC64_LINUX_FUNCTION 0x0f000000
543 #define PPC64_IPL_MESSAGE 0xc0000000
544 #define PPC64_TERM_MESSAGE 0xb0000000
545 
546 static void ppc64_do_msg(unsigned int src, const char *msg)
547 {
548 	if (ppc_md.progress) {
549 		char buf[128];
550 
551 		sprintf(buf, "%08X\n", src);
552 		ppc_md.progress(buf, 0);
553 		snprintf(buf, 128, "%s", msg);
554 		ppc_md.progress(buf, 0);
555 	}
556 }
557 
558 /* Print a boot progress message. */
559 void ppc64_boot_msg(unsigned int src, const char *msg)
560 {
561 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
562 	printk("[boot]%04x %s\n", src, msg);
563 }
564 
565 /* Print a termination message (print only -- does not stop the kernel) */
566 void ppc64_terminate_msg(unsigned int src, const char *msg)
567 {
568 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
569 	printk("[terminate]%04x %s\n", src, msg);
570 }
571 
572 void cpu_die(void)
573 {
574 	if (ppc_md.cpu_die)
575 		ppc_md.cpu_die();
576 }
577 
578 #ifdef CONFIG_SMP
579 void __init setup_per_cpu_areas(void)
580 {
581 	int i;
582 	unsigned long size;
583 	char *ptr;
584 
585 	/* Copy section for each CPU (we discard the original) */
586 	size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
587 #ifdef CONFIG_MODULES
588 	if (size < PERCPU_ENOUGH_ROOM)
589 		size = PERCPU_ENOUGH_ROOM;
590 #endif
591 
592 	for_each_possible_cpu(i) {
593 		ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
594 		if (!ptr)
595 			panic("Cannot allocate cpu data for CPU %d\n", i);
596 
597 		paca[i].data_offset = ptr - __per_cpu_start;
598 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
599 	}
600 }
601 #endif
602 
603 
604 #ifdef CONFIG_PPC_INDIRECT_IO
605 struct ppc_pci_io ppc_pci_io;
606 EXPORT_SYMBOL(ppc_pci_io);
607 #endif /* CONFIG_PPC_INDIRECT_IO */
608 
609