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 */
check_smt_enabled(void)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 */
early_smt_enabled(char * p)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 */
setup_paca(int cpu)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
early_setup(unsigned long dt_ptr)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 get_paca()->stab_real = __pa((u64)&initial_stab);
206 get_paca()->stab_addr = (u64)&initial_stab;
207
208 /* Probe the machine type */
209 probe_machine();
210
211 setup_kdump_trampoline();
212
213 DBG("Found, Initializing memory management...\n");
214
215 /*
216 * Initialize the MMU Hash table and create the linear mapping
217 * of memory. Has to be done before stab/slb initialization as
218 * this is currently where the page size encoding is obtained
219 */
220 htab_initialize();
221
222 /*
223 * Initialize stab / SLB management except on iSeries
224 */
225 if (cpu_has_feature(CPU_FTR_SLB))
226 slb_initialize();
227 else if (!firmware_has_feature(FW_FEATURE_ISERIES))
228 stab_initialize(get_paca()->stab_real);
229
230 DBG(" <- early_setup()\n");
231 }
232
233 #ifdef CONFIG_SMP
early_setup_secondary(void)234 void early_setup_secondary(void)
235 {
236 struct paca_struct *lpaca = get_paca();
237
238 /* Mark interrupts enabled in PACA */
239 lpaca->soft_enabled = 0;
240
241 /* Initialize hash table for that CPU */
242 htab_initialize_secondary();
243
244 /* Initialize STAB/SLB. We use a virtual address as it works
245 * in real mode on pSeries and we want a virutal address on
246 * iSeries anyway
247 */
248 if (cpu_has_feature(CPU_FTR_SLB))
249 slb_initialize();
250 else
251 stab_initialize(lpaca->stab_addr);
252 }
253
254 #endif /* CONFIG_SMP */
255
256 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
257 extern unsigned long __secondary_hold_spinloop;
258 extern void generic_secondary_smp_init(void);
259
smp_release_cpus(void)260 void smp_release_cpus(void)
261 {
262 unsigned long *ptr;
263
264 DBG(" -> smp_release_cpus()\n");
265
266 /* All secondary cpus are spinning on a common spinloop, release them
267 * all now so they can start to spin on their individual paca
268 * spinloops. For non SMP kernels, the secondary cpus never get out
269 * of the common spinloop.
270 */
271
272 ptr = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
273 - PHYSICAL_START);
274 *ptr = __pa(generic_secondary_smp_init);
275 mb();
276
277 DBG(" <- smp_release_cpus()\n");
278 }
279 #endif /* CONFIG_SMP || CONFIG_KEXEC */
280
281 /*
282 * Initialize some remaining members of the ppc64_caches and systemcfg
283 * structures
284 * (at least until we get rid of them completely). This is mostly some
285 * cache informations about the CPU that will be used by cache flush
286 * routines and/or provided to userland
287 */
initialize_cache_info(void)288 static void __init initialize_cache_info(void)
289 {
290 struct device_node *np;
291 unsigned long num_cpus = 0;
292
293 DBG(" -> initialize_cache_info()\n");
294
295 for (np = NULL; (np = of_find_node_by_type(np, "cpu"));) {
296 num_cpus += 1;
297
298 /* We're assuming *all* of the CPUs have the same
299 * d-cache and i-cache sizes... -Peter
300 */
301
302 if ( num_cpus == 1 ) {
303 const u32 *sizep, *lsizep;
304 u32 size, lsize;
305
306 size = 0;
307 lsize = cur_cpu_spec->dcache_bsize;
308 sizep = of_get_property(np, "d-cache-size", NULL);
309 if (sizep != NULL)
310 size = *sizep;
311 lsizep = of_get_property(np, "d-cache-block-size", NULL);
312 /* fallback if block size missing */
313 if (lsizep == NULL)
314 lsizep = of_get_property(np, "d-cache-line-size", NULL);
315 if (lsizep != NULL)
316 lsize = *lsizep;
317 if (sizep == 0 || lsizep == 0)
318 DBG("Argh, can't find dcache properties ! "
319 "sizep: %p, lsizep: %p\n", sizep, lsizep);
320
321 ppc64_caches.dsize = size;
322 ppc64_caches.dline_size = lsize;
323 ppc64_caches.log_dline_size = __ilog2(lsize);
324 ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
325
326 size = 0;
327 lsize = cur_cpu_spec->icache_bsize;
328 sizep = of_get_property(np, "i-cache-size", NULL);
329 if (sizep != NULL)
330 size = *sizep;
331 lsizep = of_get_property(np, "i-cache-block-size", NULL);
332 if (lsizep == NULL)
333 lsizep = of_get_property(np, "i-cache-line-size", NULL);
334 if (lsizep != NULL)
335 lsize = *lsizep;
336 if (sizep == 0 || lsizep == 0)
337 DBG("Argh, can't find icache properties ! "
338 "sizep: %p, lsizep: %p\n", sizep, lsizep);
339
340 ppc64_caches.isize = size;
341 ppc64_caches.iline_size = lsize;
342 ppc64_caches.log_iline_size = __ilog2(lsize);
343 ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
344 }
345 }
346
347 DBG(" <- initialize_cache_info()\n");
348 }
349
350
351 /*
352 * Do some initial setup of the system. The parameters are those which
353 * were passed in from the bootloader.
354 */
setup_system(void)355 void __init setup_system(void)
356 {
357 DBG(" -> setup_system()\n");
358
359 /* Apply the CPUs-specific and firmware specific fixups to kernel
360 * text (nop out sections not relevant to this CPU or this firmware)
361 */
362 do_feature_fixups(cur_cpu_spec->cpu_features,
363 &__start___ftr_fixup, &__stop___ftr_fixup);
364 do_feature_fixups(cur_cpu_spec->mmu_features,
365 &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
366 do_feature_fixups(powerpc_firmware_features,
367 &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
368 do_lwsync_fixups(cur_cpu_spec->cpu_features,
369 &__start___lwsync_fixup, &__stop___lwsync_fixup);
370
371 /*
372 * Unflatten the device-tree passed by prom_init or kexec
373 */
374 unflatten_device_tree();
375
376 /*
377 * Fill the ppc64_caches & systemcfg structures with informations
378 * retrieved from the device-tree.
379 */
380 initialize_cache_info();
381
382 /*
383 * Initialize irq remapping subsystem
384 */
385 irq_early_init();
386
387 #ifdef CONFIG_PPC_RTAS
388 /*
389 * Initialize RTAS if available
390 */
391 rtas_initialize();
392 #endif /* CONFIG_PPC_RTAS */
393
394 /*
395 * Check if we have an initrd provided via the device-tree
396 */
397 check_for_initrd();
398
399 /*
400 * Do some platform specific early initializations, that includes
401 * setting up the hash table pointers. It also sets up some interrupt-mapping
402 * related options that will be used by finish_device_tree()
403 */
404 if (ppc_md.init_early)
405 ppc_md.init_early();
406
407 /*
408 * We can discover serial ports now since the above did setup the
409 * hash table management for us, thus ioremap works. We do that early
410 * so that further code can be debugged
411 */
412 find_legacy_serial_ports();
413
414 /*
415 * Register early console
416 */
417 register_early_udbg_console();
418
419 /*
420 * Initialize xmon
421 */
422 xmon_setup();
423
424 check_smt_enabled();
425 smp_setup_cpu_maps();
426
427 #ifdef CONFIG_SMP
428 /* Release secondary cpus out of their spinloops at 0x60 now that
429 * we can map physical -> logical CPU ids
430 */
431 smp_release_cpus();
432 #endif
433
434 printk("Starting Linux PPC64 %s\n", init_utsname()->version);
435
436 printk("-----------------------------------------------------\n");
437 printk("ppc64_pft_size = 0x%llx\n", ppc64_pft_size);
438 printk("physicalMemorySize = 0x%llx\n", lmb_phys_mem_size());
439 if (ppc64_caches.dline_size != 0x80)
440 printk("ppc64_caches.dcache_line_size = 0x%x\n",
441 ppc64_caches.dline_size);
442 if (ppc64_caches.iline_size != 0x80)
443 printk("ppc64_caches.icache_line_size = 0x%x\n",
444 ppc64_caches.iline_size);
445 if (htab_address)
446 printk("htab_address = 0x%p\n", htab_address);
447 printk("htab_hash_mask = 0x%lx\n", htab_hash_mask);
448 if (PHYSICAL_START > 0)
449 printk("physical_start = 0x%lx\n",
450 PHYSICAL_START);
451 printk("-----------------------------------------------------\n");
452
453 DBG(" <- setup_system()\n");
454 }
455
456 #ifdef CONFIG_IRQSTACKS
irqstack_early_init(void)457 static void __init irqstack_early_init(void)
458 {
459 unsigned int i;
460
461 /*
462 * interrupt stacks must be under 256MB, we cannot afford to take
463 * SLB misses on them.
464 */
465 for_each_possible_cpu(i) {
466 softirq_ctx[i] = (struct thread_info *)
467 __va(lmb_alloc_base(THREAD_SIZE,
468 THREAD_SIZE, 0x10000000));
469 hardirq_ctx[i] = (struct thread_info *)
470 __va(lmb_alloc_base(THREAD_SIZE,
471 THREAD_SIZE, 0x10000000));
472 }
473 }
474 #else
475 #define irqstack_early_init()
476 #endif
477
478 /*
479 * Stack space used when we detect a bad kernel stack pointer, and
480 * early in SMP boots before relocation is enabled.
481 */
emergency_stack_init(void)482 static void __init emergency_stack_init(void)
483 {
484 unsigned long limit;
485 unsigned int i;
486
487 /*
488 * Emergency stacks must be under 256MB, we cannot afford to take
489 * SLB misses on them. The ABI also requires them to be 128-byte
490 * aligned.
491 *
492 * Since we use these as temporary stacks during secondary CPU
493 * bringup, we need to get at them in real mode. This means they
494 * must also be within the RMO region.
495 */
496 limit = min(0x10000000ULL, lmb.rmo_size);
497
498 for_each_possible_cpu(i) {
499 unsigned long sp;
500 sp = lmb_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
501 sp += THREAD_SIZE;
502 paca[i].emergency_sp = __va(sp);
503 }
504 }
505
506 /*
507 * Called into from start_kernel, after lock_kernel has been called.
508 * Initializes bootmem, which is unsed to manage page allocation until
509 * mem_init is called.
510 */
setup_arch(char ** cmdline_p)511 void __init setup_arch(char **cmdline_p)
512 {
513 ppc64_boot_msg(0x12, "Setup Arch");
514
515 *cmdline_p = cmd_line;
516
517 /*
518 * Set cache line size based on type of cpu as a default.
519 * Systems with OF can look in the properties on the cpu node(s)
520 * for a possibly more accurate value.
521 */
522 dcache_bsize = ppc64_caches.dline_size;
523 icache_bsize = ppc64_caches.iline_size;
524
525 /* reboot on panic */
526 panic_timeout = 180;
527
528 if (ppc_md.panic)
529 setup_panic();
530
531 init_mm.start_code = (unsigned long)_stext;
532 init_mm.end_code = (unsigned long) _etext;
533 init_mm.end_data = (unsigned long) _edata;
534 init_mm.brk = klimit;
535
536 irqstack_early_init();
537 emergency_stack_init();
538
539 stabs_alloc();
540
541 /* set up the bootmem stuff with available memory */
542 do_init_bootmem();
543 sparse_init();
544
545 #ifdef CONFIG_DUMMY_CONSOLE
546 conswitchp = &dummy_con;
547 #endif
548
549 if (ppc_md.setup_arch)
550 ppc_md.setup_arch();
551
552 paging_init();
553 ppc64_boot_msg(0x15, "Setup Done");
554 }
555
556
557 /* ToDo: do something useful if ppc_md is not yet setup. */
558 #define PPC64_LINUX_FUNCTION 0x0f000000
559 #define PPC64_IPL_MESSAGE 0xc0000000
560 #define PPC64_TERM_MESSAGE 0xb0000000
561
ppc64_do_msg(unsigned int src,const char * msg)562 static void ppc64_do_msg(unsigned int src, const char *msg)
563 {
564 if (ppc_md.progress) {
565 char buf[128];
566
567 sprintf(buf, "%08X\n", src);
568 ppc_md.progress(buf, 0);
569 snprintf(buf, 128, "%s", msg);
570 ppc_md.progress(buf, 0);
571 }
572 }
573
574 /* Print a boot progress message. */
ppc64_boot_msg(unsigned int src,const char * msg)575 void ppc64_boot_msg(unsigned int src, const char *msg)
576 {
577 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
578 printk("[boot]%04x %s\n", src, msg);
579 }
580
581 /* Print a termination message (print only -- does not stop the kernel) */
ppc64_terminate_msg(unsigned int src,const char * msg)582 void ppc64_terminate_msg(unsigned int src, const char *msg)
583 {
584 ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_TERM_MESSAGE|src, msg);
585 printk("[terminate]%04x %s\n", src, msg);
586 }
587
cpu_die(void)588 void cpu_die(void)
589 {
590 if (ppc_md.cpu_die)
591 ppc_md.cpu_die();
592 }
593
594 #ifdef CONFIG_SMP
setup_per_cpu_areas(void)595 void __init setup_per_cpu_areas(void)
596 {
597 int i;
598 unsigned long size;
599 char *ptr;
600
601 /* Copy section for each CPU (we discard the original) */
602 size = ALIGN(__per_cpu_end - __per_cpu_start, PAGE_SIZE);
603 #ifdef CONFIG_MODULES
604 if (size < PERCPU_ENOUGH_ROOM)
605 size = PERCPU_ENOUGH_ROOM;
606 #endif
607
608 for_each_possible_cpu(i) {
609 ptr = alloc_bootmem_pages_node(NODE_DATA(cpu_to_node(i)), size);
610
611 paca[i].data_offset = ptr - __per_cpu_start;
612 memcpy(ptr, __per_cpu_start, __per_cpu_end - __per_cpu_start);
613 }
614 }
615 #endif
616
617
618 #ifdef CONFIG_PPC_INDIRECT_IO
619 struct ppc_pci_io ppc_pci_io;
620 EXPORT_SYMBOL(ppc_pci_io);
621 #endif /* CONFIG_PPC_INDIRECT_IO */
622
623