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 char *smt_enabled_cmdline;
99
100 /* Look for ibm,smt-enabled OF option */
check_smt_enabled(void)101 static void check_smt_enabled(void)
102 {
103 struct device_node *dn;
104 const char *smt_option;
105
106 /* Default to enabling all threads */
107 smt_enabled_at_boot = threads_per_core;
108
109 /* Allow the command line to overrule the OF option */
110 if (smt_enabled_cmdline) {
111 if (!strcmp(smt_enabled_cmdline, "on"))
112 smt_enabled_at_boot = threads_per_core;
113 else if (!strcmp(smt_enabled_cmdline, "off"))
114 smt_enabled_at_boot = 0;
115 else {
116 long smt;
117 int rc;
118
119 rc = strict_strtol(smt_enabled_cmdline, 10, &smt);
120 if (!rc)
121 smt_enabled_at_boot =
122 min(threads_per_core, (int)smt);
123 }
124 } else {
125 dn = of_find_node_by_path("/options");
126 if (dn) {
127 smt_option = of_get_property(dn, "ibm,smt-enabled",
128 NULL);
129
130 if (smt_option) {
131 if (!strcmp(smt_option, "on"))
132 smt_enabled_at_boot = threads_per_core;
133 else if (!strcmp(smt_option, "off"))
134 smt_enabled_at_boot = 0;
135 }
136
137 of_node_put(dn);
138 }
139 }
140 }
141
142 /* Look for smt-enabled= cmdline option */
early_smt_enabled(char * p)143 static int __init early_smt_enabled(char *p)
144 {
145 smt_enabled_cmdline = p;
146 return 0;
147 }
148 early_param("smt-enabled", early_smt_enabled);
149
150 #else
151 #define check_smt_enabled()
152 #endif /* CONFIG_SMP */
153
154 /*
155 * Early initialization entry point. This is called by head.S
156 * with MMU translation disabled. We rely on the "feature" of
157 * the CPU that ignores the top 2 bits of the address in real
158 * mode so we can access kernel globals normally provided we
159 * only toy with things in the RMO region. From here, we do
160 * some early parsing of the device-tree to setup out MEMBLOCK
161 * data structures, and allocate & initialize the hash table
162 * and segment tables so we can start running with translation
163 * enabled.
164 *
165 * It is this function which will call the probe() callback of
166 * the various platform types and copy the matching one to the
167 * global ppc_md structure. Your platform can eventually do
168 * some very early initializations from the probe() routine, but
169 * this is not recommended, be very careful as, for example, the
170 * device-tree is not accessible via normal means at this point.
171 */
172
early_setup(unsigned long dt_ptr)173 void __init early_setup(unsigned long dt_ptr)
174 {
175 /* -------- printk is _NOT_ safe to use here ! ------- */
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 initialise_paca(&boot_paca, 0);
182 setup_paca(&boot_paca);
183
184 /* Initialize lockdep early or else spinlocks will blow */
185 lockdep_init();
186
187 /* -------- printk is now safe to use ------- */
188
189 /* Enable early debugging if any specified (see udbg.h) */
190 udbg_early_init();
191
192 DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
193
194 /*
195 * Do early initialization using the flattened device
196 * tree, such as retrieving the physical memory map or
197 * calculating/retrieving the hash table size.
198 */
199 early_init_devtree(__va(dt_ptr));
200
201 /* Now we know the logical id of our boot cpu, setup the paca. */
202 setup_paca(&paca[boot_cpuid]);
203
204 /* Fix up paca fields required for the boot cpu */
205 get_paca()->cpu_start = 1;
206
207 /* Probe the machine type */
208 probe_machine();
209
210 setup_kdump_trampoline();
211
212 DBG("Found, Initializing memory management...\n");
213
214 /* Initialize the hash table or TLB handling */
215 early_init_mmu();
216
217 DBG(" <- early_setup()\n");
218 }
219
220 #ifdef CONFIG_SMP
early_setup_secondary(void)221 void early_setup_secondary(void)
222 {
223 /* Mark interrupts enabled in PACA */
224 get_paca()->soft_enabled = 0;
225
226 /* Initialize the hash table or TLB handling */
227 early_init_mmu_secondary();
228 }
229
230 #endif /* CONFIG_SMP */
231
232 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
smp_release_cpus(void)233 void smp_release_cpus(void)
234 {
235 unsigned long *ptr;
236
237 DBG(" -> smp_release_cpus()\n");
238
239 /* All secondary cpus are spinning on a common spinloop, release them
240 * all now so they can start to spin on their individual paca
241 * spinloops. For non SMP kernels, the secondary cpus never get out
242 * of the common spinloop.
243 */
244
245 ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
246 - PHYSICAL_START);
247 *ptr = __pa(generic_secondary_smp_init);
248 mb();
249
250 DBG(" <- smp_release_cpus()\n");
251 }
252 #endif /* CONFIG_SMP || CONFIG_KEXEC */
253
254 /*
255 * Initialize some remaining members of the ppc64_caches and systemcfg
256 * structures
257 * (at least until we get rid of them completely). This is mostly some
258 * cache informations about the CPU that will be used by cache flush
259 * routines and/or provided to userland
260 */
initialize_cache_info(void)261 static void __init initialize_cache_info(void)
262 {
263 struct device_node *np;
264 unsigned long num_cpus = 0;
265
266 DBG(" -> initialize_cache_info()\n");
267
268 for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
269 num_cpus += 1;
270
271 /* We're assuming *all* of the CPUs have the same
272 * d-cache and i-cache sizes... -Peter
273 */
274
275 if ( num_cpus == 1 ) {
276 const u32 *sizep, *lsizep;
277 u32 size, lsize;
278
279 size = 0;
280 lsize = cur_cpu_spec->dcache_bsize;
281 sizep = of_get_property(np, "d-cache-size", NULL);
282 if (sizep != NULL)
283 size = *sizep;
284 lsizep = of_get_property(np, "d-cache-block-size", NULL);
285 /* fallback if block size missing */
286 if (lsizep == NULL)
287 lsizep = of_get_property(np, "d-cache-line-size", NULL);
288 if (lsizep != NULL)
289 lsize = *lsizep;
290 if (sizep == 0 || lsizep == 0)
291 DBG("Argh, can't find dcache properties ! "
292 "sizep: %p, lsizep: %p\n", sizep, lsizep);
293
294 ppc64_caches.dsize = size;
295 ppc64_caches.dline_size = lsize;
296 ppc64_caches.log_dline_size = __ilog2(lsize);
297 ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
298
299 size = 0;
300 lsize = cur_cpu_spec->icache_bsize;
301 sizep = of_get_property(np, "i-cache-size", NULL);
302 if (sizep != NULL)
303 size = *sizep;
304 lsizep = of_get_property(np, "i-cache-block-size", NULL);
305 if (lsizep == NULL)
306 lsizep = of_get_property(np, "i-cache-line-size", NULL);
307 if (lsizep != NULL)
308 lsize = *lsizep;
309 if (sizep == 0 || lsizep == 0)
310 DBG("Argh, can't find icache properties ! "
311 "sizep: %p, lsizep: %p\n", sizep, lsizep);
312
313 ppc64_caches.isize = size;
314 ppc64_caches.iline_size = lsize;
315 ppc64_caches.log_iline_size = __ilog2(lsize);
316 ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
317 }
318 }
319
320 DBG(" <- initialize_cache_info()\n");
321 }
322
323
324 /*
325 * Do some initial setup of the system. The parameters are those which
326 * were passed in from the bootloader.
327 */
setup_system(void)328 void __init setup_system(void)
329 {
330 DBG(" -> setup_system()\n");
331
332 /* Apply the CPUs-specific and firmware specific fixups to kernel
333 * text (nop out sections not relevant to this CPU or this firmware)
334 */
335 do_feature_fixups(cur_cpu_spec->cpu_features,
336 &__start___ftr_fixup, &__stop___ftr_fixup);
337 do_feature_fixups(cur_cpu_spec->mmu_features,
338 &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
339 do_feature_fixups(powerpc_firmware_features,
340 &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
341 do_lwsync_fixups(cur_cpu_spec->cpu_features,
342 &__start___lwsync_fixup, &__stop___lwsync_fixup);
343
344 /*
345 * Unflatten the device-tree passed by prom_init or kexec
346 */
347 unflatten_device_tree();
348
349 /*
350 * Fill the ppc64_caches & systemcfg structures with informations
351 * retrieved from the device-tree.
352 */
353 initialize_cache_info();
354
355 #ifdef CONFIG_PPC_RTAS
356 /*
357 * Initialize RTAS if available
358 */
359 rtas_initialize();
360 #endif /* CONFIG_PPC_RTAS */
361
362 /*
363 * Check if we have an initrd provided via the device-tree
364 */
365 check_for_initrd();
366
367 /*
368 * Do some platform specific early initializations, that includes
369 * setting up the hash table pointers. It also sets up some interrupt-mapping
370 * related options that will be used by finish_device_tree()
371 */
372 if (ppc_md.init_early)
373 ppc_md.init_early();
374
375 /*
376 * We can discover serial ports now since the above did setup the
377 * hash table management for us, thus ioremap works. We do that early
378 * so that further code can be debugged
379 */
380 find_legacy_serial_ports();
381
382 /*
383 * Register early console
384 */
385 register_early_udbg_console();
386
387 /*
388 * Initialize xmon
389 */
390 xmon_setup();
391
392 smp_setup_cpu_maps();
393 check_smt_enabled();
394
395 #ifdef CONFIG_SMP
396 /* Release secondary cpus out of their spinloops at 0x60 now that
397 * we can map physical -> logical CPU ids
398 */
399 smp_release_cpus();
400 #endif
401
402 printk("Starting Linux PPC64 %s\n", init_utsname()->version);
403
404 printk("-----------------------------------------------------\n");
405 printk("ppc64_pft_size = 0x%llx\n", ppc64_pft_size);
406 printk("physicalMemorySize = 0x%llx\n", memblock_phys_mem_size());
407 if (ppc64_caches.dline_size != 0x80)
408 printk("ppc64_caches.dcache_line_size = 0x%x\n",
409 ppc64_caches.dline_size);
410 if (ppc64_caches.iline_size != 0x80)
411 printk("ppc64_caches.icache_line_size = 0x%x\n",
412 ppc64_caches.iline_size);
413 #ifdef CONFIG_PPC_STD_MMU_64
414 if (htab_address)
415 printk("htab_address = 0x%p\n", htab_address);
416 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
417 #endif /* CONFIG_PPC_STD_MMU_64 */
418 if (PHYSICAL_START > 0)
419 printk("physical_start = 0x%llx\n",
420 (unsigned long long)PHYSICAL_START);
421 printk("-----------------------------------------------------\n");
422
423 DBG(" <- setup_system()\n");
424 }
425
slb0_limit(void)426 static u64 slb0_limit(void)
427 {
428 if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) {
429 return 1UL << SID_SHIFT_1T;
430 }
431 return 1UL << SID_SHIFT;
432 }
433
irqstack_early_init(void)434 static void __init irqstack_early_init(void)
435 {
436 u64 limit = slb0_limit();
437 unsigned int i;
438
439 /*
440 * Interrupt stacks must be in the first segment since we
441 * cannot afford to take SLB misses on them.
442 */
443 for_each_possible_cpu(i) {
444 softirq_ctx[i] = (struct thread_info *)
445 __va(memblock_alloc_base(THREAD_SIZE,
446 THREAD_SIZE, limit));
447 hardirq_ctx[i] = (struct thread_info *)
448 __va(memblock_alloc_base(THREAD_SIZE,
449 THREAD_SIZE, limit));
450 }
451 }
452
453 #ifdef CONFIG_PPC_BOOK3E
exc_lvl_early_init(void)454 static void __init exc_lvl_early_init(void)
455 {
456 unsigned int i;
457
458 for_each_possible_cpu(i) {
459 critirq_ctx[i] = (struct thread_info *)
460 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
461 dbgirq_ctx[i] = (struct thread_info *)
462 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
463 mcheckirq_ctx[i] = (struct thread_info *)
464 __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
465 }
466 }
467 #else
468 #define exc_lvl_early_init()
469 #endif
470
471 /*
472 * Stack space used when we detect a bad kernel stack pointer, and
473 * early in SMP boots before relocation is enabled.
474 */
emergency_stack_init(void)475 static void __init emergency_stack_init(void)
476 {
477 u64 limit;
478 unsigned int i;
479
480 /*
481 * Emergency stacks must be under 256MB, we cannot afford to take
482 * SLB misses on them. The ABI also requires them to be 128-byte
483 * aligned.
484 *
485 * Since we use these as temporary stacks during secondary CPU
486 * bringup, we need to get at them in real mode. This means they
487 * must also be within the RMO region.
488 */
489 limit = min(slb0_limit(), ppc64_rma_size);
490
491 for_each_possible_cpu(i) {
492 unsigned long sp;
493 sp = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
494 sp += THREAD_SIZE;
495 paca[i].emergency_sp = __va(sp);
496 }
497 }
498
499 /*
500 * Called into from start_kernel this initializes bootmem, which is used
501 * to manage page allocation until mem_init is called.
502 */
setup_arch(char ** cmdline_p)503 void __init setup_arch(char **cmdline_p)
504 {
505 ppc64_boot_msg(0x12, "Setup Arch");
506
507 *cmdline_p = cmd_line;
508
509 /*
510 * Set cache line size based on type of cpu as a default.
511 * Systems with OF can look in the properties on the cpu node(s)
512 * for a possibly more accurate value.
513 */
514 dcache_bsize = ppc64_caches.dline_size;
515 icache_bsize = ppc64_caches.iline_size;
516
517 /* reboot on panic */
518 panic_timeout = 180;
519
520 if (ppc_md.panic)
521 setup_panic();
522
523 init_mm.start_code = (unsigned long)_stext;
524 init_mm.end_code = (unsigned long) _etext;
525 init_mm.end_data = (unsigned long) _edata;
526 init_mm.brk = klimit;
527
528 irqstack_early_init();
529 exc_lvl_early_init();
530 emergency_stack_init();
531
532 #ifdef CONFIG_PPC_STD_MMU_64
533 stabs_alloc();
534 #endif
535 /* set up the bootmem stuff with available memory */
536 do_init_bootmem();
537 sparse_init();
538
539 #ifdef CONFIG_DUMMY_CONSOLE
540 conswitchp = &dummy_con;
541 #endif
542
543 if (ppc_md.setup_arch)
544 ppc_md.setup_arch();
545
546 paging_init();
547
548 /* Initialize the MMU context management stuff */
549 mmu_context_init();
550
551 ppc64_boot_msg(0x15, "Setup Done");
552 }
553
554
555 /* ToDo: do something useful if ppc_md is not yet setup. */
556 #define PPC64_LINUX_FUNCTION 0x0f000000
557 #define PPC64_IPL_MESSAGE 0xc0000000
558 #define PPC64_TERM_MESSAGE 0xb0000000
559
ppc64_do_msg(unsigned int src,const char * msg)560 static void ppc64_do_msg(unsigned int src, const char *msg)
561 {
562 if (ppc_md.progress) {
563 char buf[128];
564
565 sprintf(buf, "%08X\n", src);
566 ppc_md.progress(buf, 0);
567 snprintf(buf, 128, "%s", msg);
568 ppc_md.progress(buf, 0);
569 }
570 }
571
572 /* Print a boot progress message. */
ppc64_boot_msg(unsigned int src,const char * msg)573 void ppc64_boot_msg(unsigned int src, const char *msg)
574 {
575 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
576 printk("[boot]%04x %s\n", src, msg);
577 }
578
579 #ifdef CONFIG_SMP
580 #define PCPU_DYN_SIZE ()
581
pcpu_fc_alloc(unsigned int cpu,size_t size,size_t align)582 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
583 {
584 return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
585 __pa(MAX_DMA_ADDRESS));
586 }
587
pcpu_fc_free(void * ptr,size_t size)588 static void __init pcpu_fc_free(void *ptr, size_t size)
589 {
590 free_bootmem(__pa(ptr), size);
591 }
592
pcpu_cpu_distance(unsigned int from,unsigned int to)593 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
594 {
595 if (cpu_to_node(from) == cpu_to_node(to))
596 return LOCAL_DISTANCE;
597 else
598 return REMOTE_DISTANCE;
599 }
600
601 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
602 EXPORT_SYMBOL(__per_cpu_offset);
603
setup_per_cpu_areas(void)604 void __init setup_per_cpu_areas(void)
605 {
606 const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
607 size_t atom_size;
608 unsigned long delta;
609 unsigned int cpu;
610 int rc;
611
612 /*
613 * Linear mapping is one of 4K, 1M and 16M. For 4K, no need
614 * to group units. For larger mappings, use 1M atom which
615 * should be large enough to contain a number of units.
616 */
617 if (mmu_linear_psize == MMU_PAGE_4K)
618 atom_size = PAGE_SIZE;
619 else
620 atom_size = 1 << 20;
621
622 rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
623 pcpu_fc_alloc, pcpu_fc_free);
624 if (rc < 0)
625 panic("cannot initialize percpu area (err=%d)", rc);
626
627 delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
628 for_each_possible_cpu(cpu) {
629 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
630 paca[cpu].data_offset = __per_cpu_offset[cpu];
631 }
632 }
633 #endif
634
635
636 #ifdef CONFIG_PPC_INDIRECT_IO
637 struct ppc_pci_io ppc_pci_io;
638 EXPORT_SYMBOL(ppc_pci_io);
639 #endif /* CONFIG_PPC_INDIRECT_IO */
640
641