Merge commit 'ed30f24e8d07d30aa3e69d1f508f4d7bd2e8ea14' of git://git.linaro.org/landi...
[firefly-linux-kernel-4.4.55.git] / arch / powerpc / kernel / setup_64.c
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/export.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 <linux/hugetlb.h>
39
40 #include <asm/io.h>
41 #include <asm/kdump.h>
42 #include <asm/prom.h>
43 #include <asm/processor.h>
44 #include <asm/pgtable.h>
45 #include <asm/smp.h>
46 #include <asm/elf.h>
47 #include <asm/machdep.h>
48 #include <asm/paca.h>
49 #include <asm/time.h>
50 #include <asm/cputable.h>
51 #include <asm/sections.h>
52 #include <asm/btext.h>
53 #include <asm/nvram.h>
54 #include <asm/setup.h>
55 #include <asm/rtas.h>
56 #include <asm/iommu.h>
57 #include <asm/serial.h>
58 #include <asm/cache.h>
59 #include <asm/page.h>
60 #include <asm/mmu.h>
61 #include <asm/firmware.h>
62 #include <asm/xmon.h>
63 #include <asm/udbg.h>
64 #include <asm/kexec.h>
65 #include <asm/mmu_context.h>
66 #include <asm/code-patching.h>
67 #include <asm/kvm_ppc.h>
68 #include <asm/hugetlb.h>
69
70 #include "setup.h"
71
72 #ifdef DEBUG
73 #define DBG(fmt...) udbg_printf(fmt)
74 #else
75 #define DBG(fmt...)
76 #endif
77
78 int boot_cpuid = 0;
79 int __initdata spinning_secondaries;
80 u64 ppc64_pft_size;
81
82 /* Pick defaults since we might want to patch instructions
83  * before we've read this from the device tree.
84  */
85 struct ppc64_caches ppc64_caches = {
86         .dline_size = 0x40,
87         .log_dline_size = 6,
88         .iline_size = 0x40,
89         .log_iline_size = 6
90 };
91 EXPORT_SYMBOL_GPL(ppc64_caches);
92
93 /*
94  * These are used in binfmt_elf.c to put aux entries on the stack
95  * for each elf executable being started.
96  */
97 int dcache_bsize;
98 int icache_bsize;
99 int ucache_bsize;
100
101 #ifdef CONFIG_SMP
102
103 static char *smt_enabled_cmdline;
104
105 /* Look for ibm,smt-enabled OF option */
106 static void check_smt_enabled(void)
107 {
108         struct device_node *dn;
109         const char *smt_option;
110
111         /* Default to enabling all threads */
112         smt_enabled_at_boot = threads_per_core;
113
114         /* Allow the command line to overrule the OF option */
115         if (smt_enabled_cmdline) {
116                 if (!strcmp(smt_enabled_cmdline, "on"))
117                         smt_enabled_at_boot = threads_per_core;
118                 else if (!strcmp(smt_enabled_cmdline, "off"))
119                         smt_enabled_at_boot = 0;
120                 else {
121                         long smt;
122                         int rc;
123
124                         rc = strict_strtol(smt_enabled_cmdline, 10, &smt);
125                         if (!rc)
126                                 smt_enabled_at_boot =
127                                         min(threads_per_core, (int)smt);
128                 }
129         } else {
130                 dn = of_find_node_by_path("/options");
131                 if (dn) {
132                         smt_option = of_get_property(dn, "ibm,smt-enabled",
133                                                      NULL);
134
135                         if (smt_option) {
136                                 if (!strcmp(smt_option, "on"))
137                                         smt_enabled_at_boot = threads_per_core;
138                                 else if (!strcmp(smt_option, "off"))
139                                         smt_enabled_at_boot = 0;
140                         }
141
142                         of_node_put(dn);
143                 }
144         }
145 }
146
147 /* Look for smt-enabled= cmdline option */
148 static int __init early_smt_enabled(char *p)
149 {
150         smt_enabled_cmdline = p;
151         return 0;
152 }
153 early_param("smt-enabled", early_smt_enabled);
154
155 #else
156 #define check_smt_enabled()
157 #endif /* CONFIG_SMP */
158
159 /** Fix up paca fields required for the boot cpu */
160 static void fixup_boot_paca(void)
161 {
162         /* The boot cpu is started */
163         get_paca()->cpu_start = 1;
164         /* Allow percpu accesses to work until we setup percpu data */
165         get_paca()->data_offset = 0;
166 }
167
168 /*
169  * Early initialization entry point. This is called by head.S
170  * with MMU translation disabled. We rely on the "feature" of
171  * the CPU that ignores the top 2 bits of the address in real
172  * mode so we can access kernel globals normally provided we
173  * only toy with things in the RMO region. From here, we do
174  * some early parsing of the device-tree to setup out MEMBLOCK
175  * data structures, and allocate & initialize the hash table
176  * and segment tables so we can start running with translation
177  * enabled.
178  *
179  * It is this function which will call the probe() callback of
180  * the various platform types and copy the matching one to the
181  * global ppc_md structure. Your platform can eventually do
182  * some very early initializations from the probe() routine, but
183  * this is not recommended, be very careful as, for example, the
184  * device-tree is not accessible via normal means at this point.
185  */
186
187 void __init early_setup(unsigned long dt_ptr)
188 {
189         static __initdata struct paca_struct boot_paca;
190
191         /* -------- printk is _NOT_ safe to use here ! ------- */
192
193         /* Identify CPU type */
194         identify_cpu(0, mfspr(SPRN_PVR));
195
196         /* Assume we're on cpu 0 for now. Don't write to the paca yet! */
197         initialise_paca(&boot_paca, 0);
198         setup_paca(&boot_paca);
199         fixup_boot_paca();
200
201         /* Initialize lockdep early or else spinlocks will blow */
202         lockdep_init();
203
204         /* -------- printk is now safe to use ------- */
205
206         /* Enable early debugging if any specified (see udbg.h) */
207         udbg_early_init();
208
209         DBG(" -> early_setup(), dt_ptr: 0x%lx\n", dt_ptr);
210
211         /*
212          * Do early initialization using the flattened device
213          * tree, such as retrieving the physical memory map or
214          * calculating/retrieving the hash table size.
215          */
216         early_init_devtree(__va(dt_ptr));
217
218         /* Now we know the logical id of our boot cpu, setup the paca. */
219         setup_paca(&paca[boot_cpuid]);
220         fixup_boot_paca();
221
222         /* Probe the machine type */
223         probe_machine();
224
225         setup_kdump_trampoline();
226
227         DBG("Found, Initializing memory management...\n");
228
229         /* Initialize the hash table or TLB handling */
230         early_init_mmu();
231
232         /*
233          * Reserve any gigantic pages requested on the command line.
234          * memblock needs to have been initialized by the time this is
235          * called since this will reserve memory.
236          */
237         reserve_hugetlb_gpages();
238
239         DBG(" <- early_setup()\n");
240 }
241
242 #ifdef CONFIG_SMP
243 void early_setup_secondary(void)
244 {
245         /* Mark interrupts enabled in PACA */
246         get_paca()->soft_enabled = 0;
247
248         /* Initialize the hash table or TLB handling */
249         early_init_mmu_secondary();
250 }
251
252 #endif /* CONFIG_SMP */
253
254 #if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
255 void smp_release_cpus(void)
256 {
257         unsigned long *ptr;
258         int i;
259
260         DBG(" -> smp_release_cpus()\n");
261
262         /* All secondary cpus are spinning on a common spinloop, release them
263          * all now so they can start to spin on their individual paca
264          * spinloops. For non SMP kernels, the secondary cpus never get out
265          * of the common spinloop.
266          */
267
268         ptr  = (unsigned long *)((unsigned long)&__secondary_hold_spinloop
269                         - PHYSICAL_START);
270         *ptr = __pa(generic_secondary_smp_init);
271
272         /* And wait a bit for them to catch up */
273         for (i = 0; i < 100000; i++) {
274                 mb();
275                 HMT_low();
276                 if (spinning_secondaries == 0)
277                         break;
278                 udelay(1);
279         }
280         DBG("spinning_secondaries = %d\n", spinning_secondaries);
281
282         DBG(" <- smp_release_cpus()\n");
283 }
284 #endif /* CONFIG_SMP || CONFIG_KEXEC */
285
286 /*
287  * Initialize some remaining members of the ppc64_caches and systemcfg
288  * structures
289  * (at least until we get rid of them completely). This is mostly some
290  * cache informations about the CPU that will be used by cache flush
291  * routines and/or provided to userland
292  */
293 static void __init initialize_cache_info(void)
294 {
295         struct device_node *np;
296         unsigned long num_cpus = 0;
297
298         DBG(" -> initialize_cache_info()\n");
299
300         for_each_node_by_type(np, "cpu") {
301                 num_cpus += 1;
302
303                 /*
304                  * We're assuming *all* of the CPUs have the same
305                  * d-cache and i-cache sizes... -Peter
306                  */
307                 if (num_cpus == 1) {
308                         const u32 *sizep, *lsizep;
309                         u32 size, lsize;
310
311                         size = 0;
312                         lsize = cur_cpu_spec->dcache_bsize;
313                         sizep = of_get_property(np, "d-cache-size", NULL);
314                         if (sizep != NULL)
315                                 size = *sizep;
316                         lsizep = of_get_property(np, "d-cache-block-size",
317                                                  NULL);
318                         /* fallback if block size missing */
319                         if (lsizep == NULL)
320                                 lsizep = of_get_property(np,
321                                                          "d-cache-line-size",
322                                                          NULL);
323                         if (lsizep != NULL)
324                                 lsize = *lsizep;
325                         if (sizep == 0 || lsizep == 0)
326                                 DBG("Argh, can't find dcache properties ! "
327                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
328
329                         ppc64_caches.dsize = size;
330                         ppc64_caches.dline_size = lsize;
331                         ppc64_caches.log_dline_size = __ilog2(lsize);
332                         ppc64_caches.dlines_per_page = PAGE_SIZE / lsize;
333
334                         size = 0;
335                         lsize = cur_cpu_spec->icache_bsize;
336                         sizep = of_get_property(np, "i-cache-size", NULL);
337                         if (sizep != NULL)
338                                 size = *sizep;
339                         lsizep = of_get_property(np, "i-cache-block-size",
340                                                  NULL);
341                         if (lsizep == NULL)
342                                 lsizep = of_get_property(np,
343                                                          "i-cache-line-size",
344                                                          NULL);
345                         if (lsizep != NULL)
346                                 lsize = *lsizep;
347                         if (sizep == 0 || lsizep == 0)
348                                 DBG("Argh, can't find icache properties ! "
349                                     "sizep: %p, lsizep: %p\n", sizep, lsizep);
350
351                         ppc64_caches.isize = size;
352                         ppc64_caches.iline_size = lsize;
353                         ppc64_caches.log_iline_size = __ilog2(lsize);
354                         ppc64_caches.ilines_per_page = PAGE_SIZE / lsize;
355                 }
356         }
357
358         DBG(" <- initialize_cache_info()\n");
359 }
360
361
362 /*
363  * Do some initial setup of the system.  The parameters are those which 
364  * were passed in from the bootloader.
365  */
366 void __init setup_system(void)
367 {
368         DBG(" -> setup_system()\n");
369
370         /* Apply the CPUs-specific and firmware specific fixups to kernel
371          * text (nop out sections not relevant to this CPU or this firmware)
372          */
373         do_feature_fixups(cur_cpu_spec->cpu_features,
374                           &__start___ftr_fixup, &__stop___ftr_fixup);
375         do_feature_fixups(cur_cpu_spec->mmu_features,
376                           &__start___mmu_ftr_fixup, &__stop___mmu_ftr_fixup);
377         do_feature_fixups(powerpc_firmware_features,
378                           &__start___fw_ftr_fixup, &__stop___fw_ftr_fixup);
379         do_lwsync_fixups(cur_cpu_spec->cpu_features,
380                          &__start___lwsync_fixup, &__stop___lwsync_fixup);
381         do_final_fixups();
382
383         /*
384          * Unflatten the device-tree passed by prom_init or kexec
385          */
386         unflatten_device_tree();
387
388         /*
389          * Fill the ppc64_caches & systemcfg structures with informations
390          * retrieved from the device-tree.
391          */
392         initialize_cache_info();
393
394 #ifdef CONFIG_PPC_RTAS
395         /*
396          * Initialize RTAS if available
397          */
398         rtas_initialize();
399 #endif /* CONFIG_PPC_RTAS */
400
401         /*
402          * Check if we have an initrd provided via the device-tree
403          */
404         check_for_initrd();
405
406         /*
407          * Do some platform specific early initializations, that includes
408          * setting up the hash table pointers. It also sets up some interrupt-mapping
409          * related options that will be used by finish_device_tree()
410          */
411         if (ppc_md.init_early)
412                 ppc_md.init_early();
413
414         /*
415          * We can discover serial ports now since the above did setup the
416          * hash table management for us, thus ioremap works. We do that early
417          * so that further code can be debugged
418          */
419         find_legacy_serial_ports();
420
421         /*
422          * Register early console
423          */
424         register_early_udbg_console();
425
426         /*
427          * Initialize xmon
428          */
429         xmon_setup();
430
431         smp_setup_cpu_maps();
432         check_smt_enabled();
433
434 #ifdef CONFIG_SMP
435         /* Release secondary cpus out of their spinloops at 0x60 now that
436          * we can map physical -> logical CPU ids
437          */
438         smp_release_cpus();
439 #endif
440
441         printk("Starting Linux PPC64 %s\n", init_utsname()->version);
442
443         printk("-----------------------------------------------------\n");
444         printk("ppc64_pft_size                = 0x%llx\n", ppc64_pft_size);
445         printk("physicalMemorySize            = 0x%llx\n", memblock_phys_mem_size());
446         if (ppc64_caches.dline_size != 0x80)
447                 printk("ppc64_caches.dcache_line_size = 0x%x\n",
448                        ppc64_caches.dline_size);
449         if (ppc64_caches.iline_size != 0x80)
450                 printk("ppc64_caches.icache_line_size = 0x%x\n",
451                        ppc64_caches.iline_size);
452 #ifdef CONFIG_PPC_STD_MMU_64
453         if (htab_address)
454                 printk("htab_address                  = 0x%p\n", htab_address);
455         printk("htab_hash_mask                = 0x%lx\n", htab_hash_mask);
456 #endif /* CONFIG_PPC_STD_MMU_64 */
457         if (PHYSICAL_START > 0)
458                 printk("physical_start                = 0x%llx\n",
459                        (unsigned long long)PHYSICAL_START);
460         printk("-----------------------------------------------------\n");
461
462         DBG(" <- setup_system()\n");
463 }
464
465 /* This returns the limit below which memory accesses to the linear
466  * mapping are guarnateed not to cause a TLB or SLB miss. This is
467  * used to allocate interrupt or emergency stacks for which our
468  * exception entry path doesn't deal with being interrupted.
469  */
470 static u64 safe_stack_limit(void)
471 {
472 #ifdef CONFIG_PPC_BOOK3E
473         /* Freescale BookE bolts the entire linear mapping */
474         if (mmu_has_feature(MMU_FTR_TYPE_FSL_E))
475                 return linear_map_top;
476         /* Other BookE, we assume the first GB is bolted */
477         return 1ul << 30;
478 #else
479         /* BookS, the first segment is bolted */
480         if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
481                 return 1UL << SID_SHIFT_1T;
482         return 1UL << SID_SHIFT;
483 #endif
484 }
485
486 static void __init irqstack_early_init(void)
487 {
488         u64 limit = safe_stack_limit();
489         unsigned int i;
490
491         /*
492          * Interrupt stacks must be in the first segment since we
493          * cannot afford to take SLB misses on them.
494          */
495         for_each_possible_cpu(i) {
496                 softirq_ctx[i] = (struct thread_info *)
497                         __va(memblock_alloc_base(THREAD_SIZE,
498                                             THREAD_SIZE, limit));
499                 hardirq_ctx[i] = (struct thread_info *)
500                         __va(memblock_alloc_base(THREAD_SIZE,
501                                             THREAD_SIZE, limit));
502         }
503 }
504
505 #ifdef CONFIG_PPC_BOOK3E
506 static void __init exc_lvl_early_init(void)
507 {
508         extern unsigned int interrupt_base_book3e;
509         extern unsigned int exc_debug_debug_book3e;
510
511         unsigned int i;
512
513         for_each_possible_cpu(i) {
514                 critirq_ctx[i] = (struct thread_info *)
515                         __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
516                 dbgirq_ctx[i] = (struct thread_info *)
517                         __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
518                 mcheckirq_ctx[i] = (struct thread_info *)
519                         __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
520         }
521
522         if (cpu_has_feature(CPU_FTR_DEBUG_LVL_EXC))
523                 patch_branch(&interrupt_base_book3e + (0x040 / 4) + 1,
524                              (unsigned long)&exc_debug_debug_book3e, 0);
525 }
526 #else
527 #define exc_lvl_early_init()
528 #endif
529
530 /*
531  * Stack space used when we detect a bad kernel stack pointer, and
532  * early in SMP boots before relocation is enabled.
533  */
534 static void __init emergency_stack_init(void)
535 {
536         u64 limit;
537         unsigned int i;
538
539         /*
540          * Emergency stacks must be under 256MB, we cannot afford to take
541          * SLB misses on them. The ABI also requires them to be 128-byte
542          * aligned.
543          *
544          * Since we use these as temporary stacks during secondary CPU
545          * bringup, we need to get at them in real mode. This means they
546          * must also be within the RMO region.
547          */
548         limit = min(safe_stack_limit(), ppc64_rma_size);
549
550         for_each_possible_cpu(i) {
551                 unsigned long sp;
552                 sp  = memblock_alloc_base(THREAD_SIZE, THREAD_SIZE, limit);
553                 sp += THREAD_SIZE;
554                 paca[i].emergency_sp = __va(sp);
555         }
556 }
557
558 /*
559  * Called into from start_kernel this initializes bootmem, which is used
560  * to manage page allocation until mem_init is called.
561  */
562 void __init setup_arch(char **cmdline_p)
563 {
564         ppc64_boot_msg(0x12, "Setup Arch");
565
566         *cmdline_p = cmd_line;
567
568         /*
569          * Set cache line size based on type of cpu as a default.
570          * Systems with OF can look in the properties on the cpu node(s)
571          * for a possibly more accurate value.
572          */
573         dcache_bsize = ppc64_caches.dline_size;
574         icache_bsize = ppc64_caches.iline_size;
575
576         /* reboot on panic */
577         panic_timeout = 180;
578
579         if (ppc_md.panic)
580                 setup_panic();
581
582         init_mm.start_code = (unsigned long)_stext;
583         init_mm.end_code = (unsigned long) _etext;
584         init_mm.end_data = (unsigned long) _edata;
585         init_mm.brk = klimit;
586 #ifdef CONFIG_PPC_64K_PAGES
587         init_mm.context.pte_frag = NULL;
588 #endif
589         irqstack_early_init();
590         exc_lvl_early_init();
591         emergency_stack_init();
592
593 #ifdef CONFIG_PPC_STD_MMU_64
594         stabs_alloc();
595 #endif
596         /* set up the bootmem stuff with available memory */
597         do_init_bootmem();
598         sparse_init();
599
600 #ifdef CONFIG_DUMMY_CONSOLE
601         conswitchp = &dummy_con;
602 #endif
603
604         if (ppc_md.setup_arch)
605                 ppc_md.setup_arch();
606
607         paging_init();
608
609         /* Initialize the MMU context management stuff */
610         mmu_context_init();
611
612         kvm_linear_init();
613
614         /* Interrupt code needs to be 64K-aligned */
615         if ((unsigned long)_stext & 0xffff)
616                 panic("Kernelbase not 64K-aligned (0x%lx)!\n",
617                       (unsigned long)_stext);
618
619         ppc64_boot_msg(0x15, "Setup Done");
620 }
621
622
623 /* ToDo: do something useful if ppc_md is not yet setup. */
624 #define PPC64_LINUX_FUNCTION 0x0f000000
625 #define PPC64_IPL_MESSAGE 0xc0000000
626 #define PPC64_TERM_MESSAGE 0xb0000000
627
628 static void ppc64_do_msg(unsigned int src, const char *msg)
629 {
630         if (ppc_md.progress) {
631                 char buf[128];
632
633                 sprintf(buf, "%08X\n", src);
634                 ppc_md.progress(buf, 0);
635                 snprintf(buf, 128, "%s", msg);
636                 ppc_md.progress(buf, 0);
637         }
638 }
639
640 /* Print a boot progress message. */
641 void ppc64_boot_msg(unsigned int src, const char *msg)
642 {
643         ppc64_do_msg(PPC64_LINUX_FUNCTION|PPC64_IPL_MESSAGE|src, msg);
644         printk("[boot]%04x %s\n", src, msg);
645 }
646
647 #ifdef CONFIG_SMP
648 #define PCPU_DYN_SIZE           ()
649
650 static void * __init pcpu_fc_alloc(unsigned int cpu, size_t size, size_t align)
651 {
652         return __alloc_bootmem_node(NODE_DATA(cpu_to_node(cpu)), size, align,
653                                     __pa(MAX_DMA_ADDRESS));
654 }
655
656 static void __init pcpu_fc_free(void *ptr, size_t size)
657 {
658         free_bootmem(__pa(ptr), size);
659 }
660
661 static int pcpu_cpu_distance(unsigned int from, unsigned int to)
662 {
663         if (cpu_to_node(from) == cpu_to_node(to))
664                 return LOCAL_DISTANCE;
665         else
666                 return REMOTE_DISTANCE;
667 }
668
669 unsigned long __per_cpu_offset[NR_CPUS] __read_mostly;
670 EXPORT_SYMBOL(__per_cpu_offset);
671
672 void __init setup_per_cpu_areas(void)
673 {
674         const size_t dyn_size = PERCPU_MODULE_RESERVE + PERCPU_DYNAMIC_RESERVE;
675         size_t atom_size;
676         unsigned long delta;
677         unsigned int cpu;
678         int rc;
679
680         /*
681          * Linear mapping is one of 4K, 1M and 16M.  For 4K, no need
682          * to group units.  For larger mappings, use 1M atom which
683          * should be large enough to contain a number of units.
684          */
685         if (mmu_linear_psize == MMU_PAGE_4K)
686                 atom_size = PAGE_SIZE;
687         else
688                 atom_size = 1 << 20;
689
690         rc = pcpu_embed_first_chunk(0, dyn_size, atom_size, pcpu_cpu_distance,
691                                     pcpu_fc_alloc, pcpu_fc_free);
692         if (rc < 0)
693                 panic("cannot initialize percpu area (err=%d)", rc);
694
695         delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
696         for_each_possible_cpu(cpu) {
697                 __per_cpu_offset[cpu] = delta + pcpu_unit_offsets[cpu];
698                 paca[cpu].data_offset = __per_cpu_offset[cpu];
699         }
700 }
701 #endif
702
703
704 #ifdef CONFIG_PPC_INDIRECT_IO
705 struct ppc_pci_io ppc_pci_io;
706 EXPORT_SYMBOL(ppc_pci_io);
707 #endif /* CONFIG_PPC_INDIRECT_IO */
708