Merge commit 'kumar/kumar-next' into next
[linux-2.6] / arch / s390 / kernel / setup.c
1 /*
2  *  arch/s390/kernel/setup.c
3  *
4  *  S390 version
5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
6  *    Author(s): Hartmut Penner (hp@de.ibm.com),
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Derived from "arch/i386/kernel/setup.c"
10  *    Copyright (C) 1995, Linus Torvalds
11  */
12
13 /*
14  * This file handles the architecture-dependent parts of initialization
15  */
16
17 #define KMSG_COMPONENT "setup"
18 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
19
20 #include <linux/errno.h>
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/kernel.h>
24 #include <linux/mm.h>
25 #include <linux/stddef.h>
26 #include <linux/unistd.h>
27 #include <linux/ptrace.h>
28 #include <linux/slab.h>
29 #include <linux/user.h>
30 #include <linux/tty.h>
31 #include <linux/ioport.h>
32 #include <linux/delay.h>
33 #include <linux/init.h>
34 #include <linux/initrd.h>
35 #include <linux/bootmem.h>
36 #include <linux/root_dev.h>
37 #include <linux/console.h>
38 #include <linux/kernel_stat.h>
39 #include <linux/device.h>
40 #include <linux/notifier.h>
41 #include <linux/pfn.h>
42 #include <linux/ctype.h>
43 #include <linux/reboot.h>
44 #include <linux/topology.h>
45
46 #include <asm/ipl.h>
47 #include <asm/uaccess.h>
48 #include <asm/system.h>
49 #include <asm/smp.h>
50 #include <asm/mmu_context.h>
51 #include <asm/cpcmd.h>
52 #include <asm/lowcore.h>
53 #include <asm/irq.h>
54 #include <asm/page.h>
55 #include <asm/ptrace.h>
56 #include <asm/sections.h>
57 #include <asm/ebcdic.h>
58 #include <asm/compat.h>
59 #include <asm/kvm_virtio.h>
60
61 long psw_kernel_bits    = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
62                            PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
63 long psw_user_bits      = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
64                            PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
65                            PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
66
67 /*
68  * User copy operations.
69  */
70 struct uaccess_ops uaccess;
71 EXPORT_SYMBOL(uaccess);
72
73 /*
74  * Machine setup..
75  */
76 unsigned int console_mode = 0;
77 unsigned int console_devno = -1;
78 unsigned int console_irq = -1;
79 unsigned long machine_flags;
80 unsigned long elf_hwcap = 0;
81 char elf_platform[ELF_PLATFORM_SIZE];
82
83 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
84 volatile int __cpu_logical_map[NR_CPUS]; /* logical cpu to cpu address */
85 static unsigned long __initdata memory_end;
86
87 /*
88  * This is set up by the setup-routine at boot-time
89  * for S390 need to find out, what we have to setup
90  * using address 0x10400 ...
91  */
92
93 #include <asm/setup.h>
94
95 static struct resource code_resource = {
96         .name  = "Kernel code",
97         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
98 };
99
100 static struct resource data_resource = {
101         .name = "Kernel data",
102         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
103 };
104
105 /*
106  * cpu_init() initializes state that is per-CPU.
107  */
108 void __cpuinit cpu_init(void)
109 {
110         int addr = hard_smp_processor_id();
111
112         /*
113          * Store processor id in lowcore (used e.g. in timer_interrupt)
114          */
115         get_cpu_id(&S390_lowcore.cpu_data.cpu_id);
116         S390_lowcore.cpu_data.cpu_addr = addr;
117
118         /*
119          * Force FPU initialization:
120          */
121         clear_thread_flag(TIF_USEDFPU);
122         clear_used_math();
123
124         atomic_inc(&init_mm.mm_count);
125         current->active_mm = &init_mm;
126         if (current->mm)
127                 BUG();
128         enter_lazy_tlb(&init_mm, current);
129 }
130
131 /*
132  * condev= and conmode= setup parameter.
133  */
134
135 static int __init condev_setup(char *str)
136 {
137         int vdev;
138
139         vdev = simple_strtoul(str, &str, 0);
140         if (vdev >= 0 && vdev < 65536) {
141                 console_devno = vdev;
142                 console_irq = -1;
143         }
144         return 1;
145 }
146
147 __setup("condev=", condev_setup);
148
149 static int __init conmode_setup(char *str)
150 {
151 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
152         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
153                 SET_CONSOLE_SCLP;
154 #endif
155 #if defined(CONFIG_TN3215_CONSOLE)
156         if (strncmp(str, "3215", 5) == 0)
157                 SET_CONSOLE_3215;
158 #endif
159 #if defined(CONFIG_TN3270_CONSOLE)
160         if (strncmp(str, "3270", 5) == 0)
161                 SET_CONSOLE_3270;
162 #endif
163         return 1;
164 }
165
166 __setup("conmode=", conmode_setup);
167
168 static void __init conmode_default(void)
169 {
170         char query_buffer[1024];
171         char *ptr;
172
173         if (MACHINE_IS_VM) {
174                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
175                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
176                 ptr = strstr(query_buffer, "SUBCHANNEL =");
177                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
178                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
179                 ptr = strstr(query_buffer, "CONMODE");
180                 /*
181                  * Set the conmode to 3215 so that the device recognition 
182                  * will set the cu_type of the console to 3215. If the
183                  * conmode is 3270 and we don't set it back then both
184                  * 3215 and the 3270 driver will try to access the console
185                  * device (3215 as console and 3270 as normal tty).
186                  */
187                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
188                 if (ptr == NULL) {
189 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
190                         SET_CONSOLE_SCLP;
191 #endif
192                         return;
193                 }
194                 if (strncmp(ptr + 8, "3270", 4) == 0) {
195 #if defined(CONFIG_TN3270_CONSOLE)
196                         SET_CONSOLE_3270;
197 #elif defined(CONFIG_TN3215_CONSOLE)
198                         SET_CONSOLE_3215;
199 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
200                         SET_CONSOLE_SCLP;
201 #endif
202                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
203 #if defined(CONFIG_TN3215_CONSOLE)
204                         SET_CONSOLE_3215;
205 #elif defined(CONFIG_TN3270_CONSOLE)
206                         SET_CONSOLE_3270;
207 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
208                         SET_CONSOLE_SCLP;
209 #endif
210                 }
211         } else {
212 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
213                 SET_CONSOLE_SCLP;
214 #endif
215         }
216 }
217
218 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
219 static void __init setup_zfcpdump(unsigned int console_devno)
220 {
221         static char str[41];
222
223         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
224                 return;
225         if (console_devno != -1)
226                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
227                         ipl_info.data.fcp.dev_id.devno, console_devno);
228         else
229                 sprintf(str, " cio_ignore=all,!0.0.%04x",
230                         ipl_info.data.fcp.dev_id.devno);
231         strcat(boot_command_line, str);
232         console_loglevel = 2;
233 }
234 #else
235 static inline void setup_zfcpdump(unsigned int console_devno) {}
236 #endif /* CONFIG_ZFCPDUMP */
237
238  /*
239  * Reboot, halt and power_off stubs. They just call _machine_restart,
240  * _machine_halt or _machine_power_off. 
241  */
242
243 void machine_restart(char *command)
244 {
245         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
246                 /*
247                  * Only unblank the console if we are called in enabled
248                  * context or a bust_spinlocks cleared the way for us.
249                  */
250                 console_unblank();
251         _machine_restart(command);
252 }
253
254 void machine_halt(void)
255 {
256         if (!in_interrupt() || oops_in_progress)
257                 /*
258                  * Only unblank the console if we are called in enabled
259                  * context or a bust_spinlocks cleared the way for us.
260                  */
261                 console_unblank();
262         _machine_halt();
263 }
264
265 void machine_power_off(void)
266 {
267         if (!in_interrupt() || oops_in_progress)
268                 /*
269                  * Only unblank the console if we are called in enabled
270                  * context or a bust_spinlocks cleared the way for us.
271                  */
272                 console_unblank();
273         _machine_power_off();
274 }
275
276 /*
277  * Dummy power off function.
278  */
279 void (*pm_power_off)(void) = machine_power_off;
280
281 static int __init early_parse_mem(char *p)
282 {
283         memory_end = memparse(p, &p);
284         return 0;
285 }
286 early_param("mem", early_parse_mem);
287
288 #ifdef CONFIG_S390_SWITCH_AMODE
289 #ifdef CONFIG_PGSTE
290 unsigned int switch_amode = 1;
291 #else
292 unsigned int switch_amode = 0;
293 #endif
294 EXPORT_SYMBOL_GPL(switch_amode);
295
296 static int set_amode_and_uaccess(unsigned long user_amode,
297                                  unsigned long user32_amode)
298 {
299         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
300                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
301                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
302 #ifdef CONFIG_COMPAT
303         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
304                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
305                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
306         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
307                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
308                           PSW32_MASK_PSTATE;
309 #endif
310         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
311                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
312
313         if (MACHINE_HAS_MVCOS) {
314                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
315                 return 1;
316         } else {
317                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
318                 return 0;
319         }
320 }
321
322 /*
323  * Switch kernel/user addressing modes?
324  */
325 static int __init early_parse_switch_amode(char *p)
326 {
327         switch_amode = 1;
328         return 0;
329 }
330 early_param("switch_amode", early_parse_switch_amode);
331
332 #else /* CONFIG_S390_SWITCH_AMODE */
333 static inline int set_amode_and_uaccess(unsigned long user_amode,
334                                         unsigned long user32_amode)
335 {
336         return 0;
337 }
338 #endif /* CONFIG_S390_SWITCH_AMODE */
339
340 #ifdef CONFIG_S390_EXEC_PROTECT
341 unsigned int s390_noexec = 0;
342 EXPORT_SYMBOL_GPL(s390_noexec);
343
344 /*
345  * Enable execute protection?
346  */
347 static int __init early_parse_noexec(char *p)
348 {
349         if (!strncmp(p, "off", 3))
350                 return 0;
351         switch_amode = 1;
352         s390_noexec = 1;
353         return 0;
354 }
355 early_param("noexec", early_parse_noexec);
356 #endif /* CONFIG_S390_EXEC_PROTECT */
357
358 static void setup_addressing_mode(void)
359 {
360         if (s390_noexec) {
361                 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
362                                           PSW32_ASC_SECONDARY))
363                         pr_info("Execute protection active, "
364                                 "mvcos available\n");
365                 else
366                         pr_info("Execute protection active, "
367                                 "mvcos not available\n");
368         } else if (switch_amode) {
369                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
370                         pr_info("Address spaces switched, "
371                                 "mvcos available\n");
372                 else
373                         pr_info("Address spaces switched, "
374                                 "mvcos not available\n");
375         }
376 #ifdef CONFIG_TRACE_IRQFLAGS
377         sysc_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
378         io_restore_trace_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
379 #endif
380 }
381
382 static void __init
383 setup_lowcore(void)
384 {
385         struct _lowcore *lc;
386         int lc_pages;
387
388         /*
389          * Setup lowcore for boot cpu
390          */
391         lc_pages = sizeof(void *) == 8 ? 2 : 1;
392         lc = (struct _lowcore *)
393                 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
394         memset(lc, 0, lc_pages * PAGE_SIZE);
395         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
396         lc->restart_psw.addr =
397                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
398         if (switch_amode)
399                 lc->restart_psw.mask |= PSW_ASC_HOME;
400         lc->external_new_psw.mask = psw_kernel_bits;
401         lc->external_new_psw.addr =
402                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
403         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
404         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
405         lc->program_new_psw.mask = psw_kernel_bits;
406         lc->program_new_psw.addr =
407                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
408         lc->mcck_new_psw.mask =
409                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
410         lc->mcck_new_psw.addr =
411                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
412         lc->io_new_psw.mask = psw_kernel_bits;
413         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
414         lc->ipl_device = S390_lowcore.ipl_device;
415         lc->clock_comparator = -1ULL;
416         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
417         lc->async_stack = (unsigned long)
418                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
419         lc->panic_stack = (unsigned long)
420                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
421         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
422         lc->thread_info = (unsigned long) &init_thread_union;
423 #ifndef CONFIG_64BIT
424         if (MACHINE_HAS_IEEE) {
425                 lc->extended_save_area_addr = (__u32)
426                         __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0);
427                 /* enable extended save area */
428                 __ctl_set_bit(14, 29);
429         }
430 #else
431         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
432 #endif
433         set_prefix((u32)(unsigned long) lc);
434 }
435
436 static void __init
437 setup_resources(void)
438 {
439         struct resource *res, *sub_res;
440         int i;
441
442         code_resource.start = (unsigned long) &_text;
443         code_resource.end = (unsigned long) &_etext - 1;
444         data_resource.start = (unsigned long) &_etext;
445         data_resource.end = (unsigned long) &_edata - 1;
446
447         for (i = 0; i < MEMORY_CHUNKS; i++) {
448                 if (!memory_chunk[i].size)
449                         continue;
450                 res = alloc_bootmem_low(sizeof(struct resource));
451                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
452                 switch (memory_chunk[i].type) {
453                 case CHUNK_READ_WRITE:
454                         res->name = "System RAM";
455                         break;
456                 case CHUNK_READ_ONLY:
457                         res->name = "System ROM";
458                         res->flags |= IORESOURCE_READONLY;
459                         break;
460                 default:
461                         res->name = "reserved";
462                 }
463                 res->start = memory_chunk[i].addr;
464                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
465                 request_resource(&iomem_resource, res);
466
467                 if (code_resource.start >= res->start  &&
468                         code_resource.start <= res->end &&
469                         code_resource.end > res->end) {
470                         sub_res = alloc_bootmem_low(sizeof(struct resource));
471                         memcpy(sub_res, &code_resource,
472                                 sizeof(struct resource));
473                         sub_res->end = res->end;
474                         code_resource.start = res->end + 1;
475                         request_resource(res, sub_res);
476                 }
477
478                 if (code_resource.start >= res->start &&
479                         code_resource.start <= res->end &&
480                         code_resource.end <= res->end)
481                         request_resource(res, &code_resource);
482
483                 if (data_resource.start >= res->start &&
484                         data_resource.start <= res->end &&
485                         data_resource.end > res->end) {
486                         sub_res = alloc_bootmem_low(sizeof(struct resource));
487                         memcpy(sub_res, &data_resource,
488                                 sizeof(struct resource));
489                         sub_res->end = res->end;
490                         data_resource.start = res->end + 1;
491                         request_resource(res, sub_res);
492                 }
493
494                 if (data_resource.start >= res->start &&
495                         data_resource.start <= res->end &&
496                         data_resource.end <= res->end)
497                         request_resource(res, &data_resource);
498         }
499 }
500
501 unsigned long real_memory_size;
502 EXPORT_SYMBOL_GPL(real_memory_size);
503
504 static void __init setup_memory_end(void)
505 {
506         unsigned long memory_size;
507         unsigned long max_mem;
508         int i;
509
510 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
511         if (ipl_info.type == IPL_TYPE_FCP_DUMP)
512                 memory_end = ZFCPDUMP_HSA_SIZE;
513 #endif
514         memory_size = 0;
515         memory_end &= PAGE_MASK;
516
517         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
518         memory_end = min(max_mem, memory_end);
519
520         /*
521          * Make sure all chunks are MAX_ORDER aligned so we don't need the
522          * extra checks that HOLES_IN_ZONE would require.
523          */
524         for (i = 0; i < MEMORY_CHUNKS; i++) {
525                 unsigned long start, end;
526                 struct mem_chunk *chunk;
527                 unsigned long align;
528
529                 chunk = &memory_chunk[i];
530                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
531                 start = (chunk->addr + align - 1) & ~(align - 1);
532                 end = (chunk->addr + chunk->size) & ~(align - 1);
533                 if (start >= end)
534                         memset(chunk, 0, sizeof(*chunk));
535                 else {
536                         chunk->addr = start;
537                         chunk->size = end - start;
538                 }
539         }
540
541         for (i = 0; i < MEMORY_CHUNKS; i++) {
542                 struct mem_chunk *chunk = &memory_chunk[i];
543
544                 real_memory_size = max(real_memory_size,
545                                        chunk->addr + chunk->size);
546                 if (chunk->addr >= max_mem) {
547                         memset(chunk, 0, sizeof(*chunk));
548                         continue;
549                 }
550                 if (chunk->addr + chunk->size > max_mem)
551                         chunk->size = max_mem - chunk->addr;
552                 memory_size = max(memory_size, chunk->addr + chunk->size);
553         }
554         if (!memory_end)
555                 memory_end = memory_size;
556 }
557
558 static void __init
559 setup_memory(void)
560 {
561         unsigned long bootmap_size;
562         unsigned long start_pfn, end_pfn;
563         int i;
564
565         /*
566          * partially used pages are not usable - thus
567          * we are rounding upwards:
568          */
569         start_pfn = PFN_UP(__pa(&_end));
570         end_pfn = max_pfn = PFN_DOWN(memory_end);
571
572 #ifdef CONFIG_BLK_DEV_INITRD
573         /*
574          * Move the initrd in case the bitmap of the bootmem allocater
575          * would overwrite it.
576          */
577
578         if (INITRD_START && INITRD_SIZE) {
579                 unsigned long bmap_size;
580                 unsigned long start;
581
582                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
583                 bmap_size = PFN_PHYS(bmap_size);
584
585                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
586                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
587
588                         if (start + INITRD_SIZE > memory_end) {
589                                 pr_err("initrd extends beyond end of "
590                                        "memory (0x%08lx > 0x%08lx) "
591                                        "disabling initrd\n",
592                                        start + INITRD_SIZE, memory_end);
593                                 INITRD_START = INITRD_SIZE = 0;
594                         } else {
595                                 pr_info("Moving initrd (0x%08lx -> "
596                                         "0x%08lx, size: %ld)\n",
597                                         INITRD_START, start, INITRD_SIZE);
598                                 memmove((void *) start, (void *) INITRD_START,
599                                         INITRD_SIZE);
600                                 INITRD_START = start;
601                         }
602                 }
603         }
604 #endif
605
606         /*
607          * Initialize the boot-time allocator
608          */
609         bootmap_size = init_bootmem(start_pfn, end_pfn);
610
611         /*
612          * Register RAM areas with the bootmem allocator.
613          */
614
615         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
616                 unsigned long start_chunk, end_chunk, pfn;
617
618                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
619                         continue;
620                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
621                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
622                 end_chunk = min(end_chunk, end_pfn);
623                 if (start_chunk >= end_chunk)
624                         continue;
625                 add_active_range(0, start_chunk, end_chunk);
626                 pfn = max(start_chunk, start_pfn);
627                 for (; pfn < end_chunk; pfn++)
628                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
629         }
630
631         psw_set_key(PAGE_DEFAULT_KEY);
632
633         free_bootmem_with_active_regions(0, max_pfn);
634
635         /*
636          * Reserve memory used for lowcore/command line/kernel image.
637          */
638         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
639         reserve_bootmem((unsigned long)_stext,
640                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
641                         BOOTMEM_DEFAULT);
642         /*
643          * Reserve the bootmem bitmap itself as well. We do this in two
644          * steps (first step was init_bootmem()) because this catches
645          * the (very unlikely) case of us accidentally initializing the
646          * bootmem allocator with an invalid RAM area.
647          */
648         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
649                         BOOTMEM_DEFAULT);
650
651 #ifdef CONFIG_BLK_DEV_INITRD
652         if (INITRD_START && INITRD_SIZE) {
653                 if (INITRD_START + INITRD_SIZE <= memory_end) {
654                         reserve_bootmem(INITRD_START, INITRD_SIZE,
655                                         BOOTMEM_DEFAULT);
656                         initrd_start = INITRD_START;
657                         initrd_end = initrd_start + INITRD_SIZE;
658                 } else {
659                         pr_err("initrd extends beyond end of "
660                                "memory (0x%08lx > 0x%08lx) "
661                                "disabling initrd\n",
662                                initrd_start + INITRD_SIZE, memory_end);
663                         initrd_start = initrd_end = 0;
664                 }
665         }
666 #endif
667 }
668
669 /*
670  * Setup hardware capabilities.
671  */
672 static void __init setup_hwcaps(void)
673 {
674         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
675         struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
676         unsigned long long facility_list_extended;
677         unsigned int facility_list;
678         int i;
679
680         facility_list = stfl();
681         /*
682          * The store facility list bits numbers as found in the principles
683          * of operation are numbered with bit 1UL<<31 as number 0 to
684          * bit 1UL<<0 as number 31.
685          *   Bit 0: instructions named N3, "backported" to esa-mode
686          *   Bit 2: z/Architecture mode is active
687          *   Bit 7: the store-facility-list-extended facility is installed
688          *   Bit 17: the message-security assist is installed
689          *   Bit 19: the long-displacement facility is installed
690          *   Bit 21: the extended-immediate facility is installed
691          * These get translated to:
692          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
693          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
694          *   HWCAP_S390_LDISP bit 4, and HWCAP_S390_EIMM bit 5.
695          */
696         for (i = 0; i < 6; i++)
697                 if (facility_list & (1UL << (31 - stfl_bits[i])))
698                         elf_hwcap |= 1UL << i;
699
700         /*
701          * Check for additional facilities with store-facility-list-extended.
702          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
703          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
704          * as stored by stfl, bits 32-xxx contain additional facilities.
705          * How many facility words are stored depends on the number of
706          * doublewords passed to the instruction. The additional facilites
707          * are:
708          *   Bit 43: decimal floating point facility is installed
709          * translated to:
710          *   HWCAP_S390_DFP bit 6.
711          */
712         if ((elf_hwcap & (1UL << 2)) &&
713             __stfle(&facility_list_extended, 1) > 0) {
714                 if (facility_list_extended & (1ULL << (64 - 43)))
715                         elf_hwcap |= 1UL << 6;
716         }
717
718         if (MACHINE_HAS_HPAGE)
719                 elf_hwcap |= 1UL << 7;
720
721         switch (cpuinfo->cpu_id.machine) {
722         case 0x9672:
723 #if !defined(CONFIG_64BIT)
724         default:        /* Use "g5" as default for 31 bit kernels. */
725 #endif
726                 strcpy(elf_platform, "g5");
727                 break;
728         case 0x2064:
729         case 0x2066:
730 #if defined(CONFIG_64BIT)
731         default:        /* Use "z900" as default for 64 bit kernels. */
732 #endif
733                 strcpy(elf_platform, "z900");
734                 break;
735         case 0x2084:
736         case 0x2086:
737                 strcpy(elf_platform, "z990");
738                 break;
739         case 0x2094:
740         case 0x2096:
741                 strcpy(elf_platform, "z9-109");
742                 break;
743         case 0x2097:
744         case 0x2098:
745                 strcpy(elf_platform, "z10");
746                 break;
747         }
748 }
749
750 /*
751  * Setup function called from init/main.c just after the banner
752  * was printed.
753  */
754
755 void __init
756 setup_arch(char **cmdline_p)
757 {
758         /* set up preferred console */
759         add_preferred_console("ttyS", 0, NULL);
760
761         /*
762          * print what head.S has found out about the machine
763          */
764 #ifndef CONFIG_64BIT
765         if (MACHINE_IS_VM)
766                 pr_info("Linux is running as a z/VM "
767                         "guest operating system in 31-bit mode\n");
768         else
769                 pr_info("Linux is running natively in 31-bit mode\n");
770         if (MACHINE_HAS_IEEE)
771                 pr_info("The hardware system has IEEE compatible "
772                         "floating point units\n");
773         else
774                 pr_info("The hardware system has no IEEE compatible "
775                         "floating point units\n");
776 #else /* CONFIG_64BIT */
777         if (MACHINE_IS_VM)
778                 pr_info("Linux is running as a z/VM "
779                         "guest operating system in 64-bit mode\n");
780         else if (MACHINE_IS_KVM) {
781                 pr_info("Linux is running under KVM in 64-bit mode\n");
782                 add_preferred_console("hvc", 0, NULL);
783                 s390_virtio_console_init();
784         } else
785                 pr_info("Linux is running natively in 64-bit mode\n");
786 #endif /* CONFIG_64BIT */
787
788         /* Have one command line that is parsed and saved in /proc/cmdline */
789         /* boot_command_line has been already set up in early.c */
790         *cmdline_p = boot_command_line;
791
792         ROOT_DEV = Root_RAM0;
793
794         init_mm.start_code = PAGE_OFFSET;
795         init_mm.end_code = (unsigned long) &_etext;
796         init_mm.end_data = (unsigned long) &_edata;
797         init_mm.brk = (unsigned long) &_end;
798
799         if (MACHINE_HAS_MVCOS)
800                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
801         else
802                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
803
804         parse_early_param();
805
806         setup_ipl();
807         setup_memory_end();
808         setup_addressing_mode();
809         setup_memory();
810         setup_resources();
811         setup_lowcore();
812
813         cpu_init();
814         __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
815         s390_init_cpu_topology();
816
817         /*
818          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
819          */
820         setup_hwcaps();
821
822         /*
823          * Create kernel page tables and switch to virtual addressing.
824          */
825         paging_init();
826
827         /* Setup default console */
828         conmode_default();
829
830         /* Setup zfcpdump support */
831         setup_zfcpdump(console_devno);
832 }