xref: /linux/arch/powerpc/kernel/setup_64.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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 #ifdef CONFIG_SMP
104 
105 static int smt_enabled_cmdline;
106 
107 /* Look for ibm,smt-enabled OF option */
108 static void check_smt_enabled(void)
109 {
110 	struct device_node *dn;
111 	char *smt_option;
112 
113 	/* Allow the command line to overrule the OF option */
114 	if (smt_enabled_cmdline)
115 		return;
116 
117 	dn = of_find_node_by_path("/options");
118 
119 	if (dn) {
120 		smt_option = (char *)get_property(dn, "ibm,smt-enabled", NULL);
121 
122                 if (smt_option) {
123 			if (!strcmp(smt_option, "on"))
124 				smt_enabled_at_boot = 1;
125 			else if (!strcmp(smt_option, "off"))
126 				smt_enabled_at_boot = 0;
127                 }
128         }
129 }
130 
131 /* Look for smt-enabled= cmdline option */
132 static int __init early_smt_enabled(char *p)
133 {
134 	smt_enabled_cmdline = 1;
135 
136 	if (!p)
137 		return 0;
138 
139 	if (!strcmp(p, "on") || !strcmp(p, "1"))
140 		smt_enabled_at_boot = 1;
141 	else if (!strcmp(p, "off") || !strcmp(p, "0"))
142 		smt_enabled_at_boot = 0;
143 
144 	return 0;
145 }
146 early_param("smt-enabled", early_smt_enabled);
147 
148 #else
149 #define check_smt_enabled()
150 #endif /* CONFIG_SMP */
151 
152 /* Put the paca pointer into r13 and SPRG3 */
153 void __init setup_paca(int cpu)
154 {
155 	local_paca = &paca[cpu];
156 	mtspr(SPRN_SPRG3, local_paca);
157 }
158 
159 /*
160  * Early initialization entry point. This is called by head.S
161  * with MMU translation disabled. We rely on the "feature" of
162  * the CPU that ignores the top 2 bits of the address in real
163  * mode so we can access kernel globals normally provided we
164  * only toy with things in the RMO region. From here, we do
165  * some early parsing of the device-tree to setup out LMB
166  * data structures, and allocate & initialize the hash table
167  * and segment tables so we can start running with translation
168  * enabled.
169  *
170  * It is this function which will call the probe() callback of
171  * the various platform types and copy the matching one to the
172  * global ppc_md structure. Your platform can eventually do
173  * some very early initializations from the probe() routine, but
174  * this is not recommended, be very careful as, for example, the
175  * device-tree is not accessible via normal means at this point.
176  */
177 
178 void __init early_setup(unsigned long dt_ptr)
179 {
180 	/* Assume we're on cpu 0 for now. Don't write to the paca yet! */
181 	setup_paca(0);
182 
183 	/* Enable early debugging if any specified (see udbg.h) */
184 	udbg_early_init();
185 
186  	DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
187 
188 	/*
189 	 * Do early initializations using the flattened device
190 	 * tree, like retreiving the physical memory map or
191 	 * calculating/retreiving the hash table size
192 	 */
193 	early_init_devtree(__va(dt_ptr));
194 
195 	/* Now we know the logical id of our boot cpu, setup the paca. */
196 	setup_paca(boot_cpuid);
197 
198 	/* Fix up paca fields required for the boot cpu */
199 	get_paca()->cpu_start = 1;
200 	get_paca()->stab_real = __pa((u64)&initial_stab);
201 	get_paca()->stab_addr = (u64)&initial_stab;
202 
203 	/* Probe the machine type */
204 	probe_machine();
205 
206 	setup_kdump_trampoline();
207 
208 	DBG("Found, Initializing memory management...\n");
209 
210 	/*
211 	 * Initialize the MMU Hash table and create the linear mapping
212 	 * of memory. Has to be done before stab/slb initialization as
213 	 * this is currently where the page size encoding is obtained
214 	 */
215 	htab_initialize();
216 
217 	/*
218 	 * Initialize stab / SLB management except on iSeries
219 	 */
220 	if (cpu_has_feature(CPU_FTR_SLB))
221 		slb_initialize();
222 	else if (!firmware_has_feature(FW_FEATURE_ISERIES))
223 		stab_initialize(get_paca()->stab_real);
224 
225 	DBG(" <- early_setup()\n");
226 }
227 
228 #ifdef CONFIG_SMP
229 void early_setup_secondary(void)
230 {
231 	struct paca_struct *lpaca = get_paca();
232 
233 	/* Mark enabled in PACA */
234 	lpaca->proc_enabled = 0;
235 
236 	/* Initialize hash table for that CPU */
237 	htab_initialize_secondary();
238 
239 	/* Initialize STAB/SLB. We use a virtual address as it works
240 	 * in real mode on pSeries and we want a virutal address on
241 	 * iSeries anyway
242 	 */
243 	if (cpu_has_feature(CPU_FTR_SLB))
244 		slb_initialize();
245 	else
246 		stab_initialize(lpaca->stab_addr);
247 }
248 
249 #endif /* CONFIG_SMP */
250 
251 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
252 void smp_release_cpus(void)
253 {
254 	extern unsigned long __secondary_hold_spinloop;
255 	unsigned long *ptr;
256 
257 	DBG(" -> smp_release_cpus()\n");
258 
259 	/* All secondary cpus are spinning on a common spinloop, release them
260 	 * all now so they can start to spin on their individual paca
261 	 * spinloops. For non SMP kernels, the secondary cpus never get out
262 	 * of the common spinloop.
263 	 * This is useless but harmless on iSeries, secondaries are already
264 	 * waiting on their paca spinloops. */
265 
266 	ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
267 			- PHYSICAL_START);
268 	*ptr = 1;
269 	mb();
270 
271 	DBG(" <- smp_release_cpus()\n");
272 }
273 #endif /* CONFIG_SMP || CONFIG_KEXEC */
274 
275 /*
276  * Initialize some remaining members of the ppc64_caches and systemcfg
277  * structures
278  * (at least until we get rid of them completely). This is mostly some
279  * cache informations about the CPU that will be used by cache flush
280  * routines and/or provided to userland
281  */
282 static void __init initialize_cache_info(void)
283 {
284 	struct device_node *np;
285 	unsigned long num_cpus = 0;
286 
287 	DBG(" -> initialize_cache_info()\n");
288 
289 	for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
290 		num_cpus += 1;
291 
292 		/* We're assuming *all* of the CPUs have the same
293 		 * d-cache and i-cache sizes... -Peter
294 		 */
295 
296 		if ( num_cpus == 1 ) {
297 			u32 *sizep, *lsizep;
298 			u32 size, lsize;
299 			const char *dc, *ic;
300 
301 			/* Then read cache informations */
302 			if (machine_is(powermac)) {
303 				dc = "d-cache-block-size";
304 				ic = "i-cache-block-size";
305 			} else {
306 				dc = "d-cache-line-size";
307 				ic = "i-cache-line-size";
308 			}
309 
310 			size = 0;
311 			lsize = cur_cpu_spec->dcache_bsize;
312 			sizep = (u32 *)get_property(np, "d-cache-size", NULL);
313 			if (sizep != NULL)
314 				size = *sizep;
315 			lsizep = (u32 *) get_property(np, dc, NULL);
316 			if (lsizep != NULL)
317 				lsize = *lsizep;
318 			if (sizep == 0 || lsizep == 0)
319 				DBG("Argh, can't find dcache properties ! "
320 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
321 
322 			ppc64_caches.dsize = size;
323 			ppc64_caches.dline_size = lsize;
324 			ppc64_caches.log_dline_size = __ilog2(lsize);
325 			ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
326 
327 			size = 0;
328 			lsize = cur_cpu_spec->icache_bsize;
329 			sizep = (u32 *)get_property(np, "i-cache-size", NULL);
330 			if (sizep != NULL)
331 				size = *sizep;
332 			lsizep = (u32 *)get_property(np, ic, NULL);
333 			if (lsizep != NULL)
334 				lsize = *lsizep;
335 			if (sizep == 0 || lsizep == 0)
336 				DBG("Argh, can't find icache properties ! "
337 				    "sizep: %p, lsizep: %p\n", sizep, lsizep);
338 
339 			ppc64_caches.isize = size;
340 			ppc64_caches.iline_size = lsize;
341 			ppc64_caches.log_iline_size = __ilog2(lsize);
342 			ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
343 		}
344 	}
345 
346 	DBG(" <- initialize_cache_info()\n");
347 }
348 
349 
350 /*
351  * Do some initial setup of the system.  The parameters are those which
352  * were passed in from the bootloader.
353  */
354 void __init setup_system(void)
355 {
356 	DBG(" -> setup_system()\n");
357 
358 	/*
359 	 * Unflatten the device-tree passed by prom_init or kexec
360 	 */
361 	unflatten_device_tree();
362 
363 	/*
364 	 * Fill the ppc64_caches & systemcfg structures with informations
365 	 * retrieved from the device-tree. Need to be called before
366 	 * finish_device_tree() since the later requires some of the
367 	 * informations filled up here to properly parse the interrupt tree.
368 	 */
369 	initialize_cache_info();
370 
371 #ifdef CONFIG_PPC_RTAS
372 	/*
373 	 * Initialize RTAS if available
374 	 */
375 	rtas_initialize();
376 #endif /* CONFIG_PPC_RTAS */
377 
378 	/*
379 	 * Check if we have an initrd provided via the device-tree
380 	 */
381 	check_for_initrd();
382 
383 	/*
384 	 * Do some platform specific early initializations, that includes
385 	 * setting up the hash table pointers. It also sets up some interrupt-mapping
386 	 * related options that will be used by finish_device_tree()
387 	 */
388 	ppc_md.init_early();
389 
390  	/*
391 	 * We can discover serial ports now since the above did setup the
392 	 * hash table management for us, thus ioremap works. We do that early
393 	 * so that further code can be debugged
394 	 */
395 	find_legacy_serial_ports();
396 
397 	/*
398 	 * "Finish" the device-tree, that is do the actual parsing of
399 	 * some of the properties like the interrupt map
400 	 */
401 	finish_device_tree();
402 
403 	/*
404 	 * Initialize xmon
405 	 */
406 #ifdef CONFIG_XMON_DEFAULT
407 	xmon_init(1);
408 #endif
409 	/*
410 	 * Register early console
411 	 */
412 	register_early_udbg_console();
413 
414 	if (do_early_xmon)
415 		debugger(NULL);
416 
417 	check_smt_enabled();
418 	smp_setup_cpu_maps();
419 
420 #ifdef CONFIG_SMP
421 	/* Release secondary cpus out of their spinloops at 0x60 now that
422 	 * we can map physical -> logical CPU ids
423 	 */
424 	smp_release_cpus();
425 #endif
426 
427 	printk("Starting Linux PPC64 %s\n", system_utsname.version);
428 
429 	printk("-----------------------------------------------------\n");
430 	printk("ppc64_pft_size                = 0x%lx\n", ppc64_pft_size);
431 	printk("ppc64_interrupt_controller    = 0x%ld\n",
432 	       ppc64_interrupt_controller);
433 	printk("physicalMemorySize            = 0x%lx\n", lmb_phys_mem_size());
434 	printk("ppc64_caches.dcache_line_size = 0x%x\n",
435 	       ppc64_caches.dline_size);
436 	printk("ppc64_caches.icache_line_size = 0x%x\n",
437 	       ppc64_caches.iline_size);
438 	printk("htab_address                  = 0x%p\n", htab_address);
439 	printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
440 #if PHYSICAL_START > 0
441 	printk("physical_start                = 0x%x\n", PHYSICAL_START);
442 #endif
443 	printk("-----------------------------------------------------\n");
444 
445 	DBG(" <- setup_system()\n");
446 }
447 
448 #ifdef CONFIG_IRQSTACKS
449 static void __init irqstack_early_init(void)
450 {
451 	unsigned int i;
452 
453 	/*
454 	 * interrupt stacks must be under 256MB, we cannot afford to take
455 	 * SLB misses on them.
456 	 */
457 	for_each_possible_cpu(i) {
458 		softirq_ctx[i] = (struct thread_info *)
459 			__va(lmb_alloc_base(THREAD_SIZE,
460 					    THREAD_SIZE, 0x10000000));
461 		hardirq_ctx[i] = (struct thread_info *)
462 			__va(lmb_alloc_base(THREAD_SIZE,
463 					    THREAD_SIZE, 0x10000000));
464 	}
465 }
466 #else
467 #define irqstack_early_init()
468 #endif
469 
470 /*
471  * Stack space used when we detect a bad kernel stack pointer, and
472  * early in SMP boots before relocation is enabled.
473  */
474 static void __init emergency_stack_init(void)
475 {
476 	unsigned long limit;
477 	unsigned int i;
478 
479 	/*
480 	 * Emergency stacks must be under 256MB, we cannot afford to take
481 	 * SLB misses on them. The ABI also requires them to be 128-byte
482 	 * aligned.
483 	 *
484 	 * Since we use these as temporary stacks during secondary CPU
485 	 * bringup, we need to get at them in real mode. This means they
486 	 * must also be within the RMO region.
487 	 */
488 	limit = min(0x10000000UL, lmb.rmo_size);
489 
490 	for_each_possible_cpu(i)
491 		paca[i].emergency_sp =
492 		__va(lmb_alloc_base(HW_PAGE_SIZE, 128, limit)) + HW_PAGE_SIZE;
493 }
494 
495 /*
496  * Called into from start_kernel, after lock_kernel has been called.
497  * Initializes bootmem, which is unsed to manage page allocation until
498  * mem_init is called.
499  */
500 void __init setup_arch(char **cmdline_p)
501 {
502 	ppc64_boot_msg(0x12, "Setup Arch");
503 
504 	*cmdline_p = cmd_line;
505 
506 	/*
507 	 * Set cache line size based on type of cpu as a default.
508 	 * Systems with OF can look in the properties on the cpu node(s)
509 	 * for a possibly more accurate value.
510 	 */
511 	dcache_bsize = ppc64_caches.dline_size;
512 	icache_bsize = ppc64_caches.iline_size;
513 
514 	/* reboot on panic */
515 	panic_timeout = 180;
516 
517 	if (ppc_md.panic)
518 		setup_panic();
519 
520 	init_mm.start_code = PAGE_OFFSET;
521 	init_mm.end_code = (unsigned long) _etext;
522 	init_mm.end_data = (unsigned long) _edata;
523 	init_mm.brk = klimit;
524 
525 	irqstack_early_init();
526 	emergency_stack_init();
527 
528 	stabs_alloc();
529 
530 	/* set up the bootmem stuff with available memory */
531 	do_init_bootmem();
532 	sparse_init();
533 
534 #ifdef CONFIG_DUMMY_CONSOLE
535 	conswitchp = &dummy_con;
536 #endif
537 
538 	ppc_md.setup_arch();
539 
540 	paging_init();
541 	ppc64_boot_msg(0x15, "Setup Done");
542 }
543 
544 
545 /* ToDo: do something useful if ppc_md is not yet setup. */
546 #define PPC64_LINUX_FUNCTION 0x0f000000
547 #define PPC64_IPL_MESSAGE 0xc0000000
548 #define PPC64_TERM_MESSAGE 0xb0000000
549 
550 static void ppc64_do_msg(unsigned int src, const char *msg)
551 {
552 	if (ppc_md.progress) {
553 		char buf[128];
554 
555 		sprintf(buf, "%08X\n", src);
556 		ppc_md.progress(buf, 0);
557 		snprintf(buf, 128, "%s", msg);
558 		ppc_md.progress(buf, 0);
559 	}
560 }
561 
562 /* Print a boot progress message. */
563 void ppc64_boot_msg(unsigned int src, const char *msg)
564 {
565 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
566 	printk("[boot]%04x %s\n", src, msg);
567 }
568 
569 /* Print a termination message (print only -- does not stop the kernel) */
570 void ppc64_terminate_msg(unsigned int src, const char *msg)
571 {
572 	ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
573 	printk("[terminate]%04x %s\n", src, msg);
574 }
575 
576 void cpu_die(void)
577 {
578 	if (ppc_md.cpu_die)
579 		ppc_md.cpu_die();
580 }
581 
582 #ifdef CONFIG_SMP
583 void __init setup_per_cpu_areas(void)
584 {
585 	int i;
586 	unsigned long size;
587 	char *ptr;
588 
589 	/* Copy section for each CPU (we discard the original) */
590 	size = ALIGN(__per_cpu_end - __per_cpu_start, SMP_CACHE_BYTES);
591 #ifdef CONFIG_MODULES
592 	if (size < PERCPU_ENOUGH_ROOM)
593 		size = PERCPU_ENOUGH_ROOM;
594 #endif
595 
596 	for_each_possible_cpu(i) {
597 		ptr = alloc_bootmem_node(NODE_DATA(cpu_to_node(i)), size);
598 		if (!ptr)
599 			panic("Cannot allocate cpu data for CPU %d\n", i);
600 
601 		paca[i].data_offset = ptr - __per_cpu_start;
602 		memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
603 	}
604 }
605 #endif
606