Merge branch 'docs-next' of git://git.lwn.net/linux-2.6
[pandora-kernel.git] / arch / s390 / kernel / setup.c
1 /*
2  *  arch/s390/kernel/setup.c
3  *
4  *  S390 version
5  *    Copyright (C) IBM Corp. 1999,2010
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/user.h>
29 #include <linux/tty.h>
30 #include <linux/ioport.h>
31 #include <linux/delay.h>
32 #include <linux/init.h>
33 #include <linux/initrd.h>
34 #include <linux/bootmem.h>
35 #include <linux/root_dev.h>
36 #include <linux/console.h>
37 #include <linux/kernel_stat.h>
38 #include <linux/device.h>
39 #include <linux/notifier.h>
40 #include <linux/pfn.h>
41 #include <linux/ctype.h>
42 #include <linux/reboot.h>
43 #include <linux/topology.h>
44 #include <linux/ftrace.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 EXPORT_SYMBOL(console_mode);
78
79 unsigned int console_devno = -1;
80 EXPORT_SYMBOL(console_devno);
81
82 unsigned int console_irq = -1;
83 EXPORT_SYMBOL(console_irq);
84
85 unsigned long elf_hwcap = 0;
86 char elf_platform[ELF_PLATFORM_SIZE];
87
88 struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
89
90 int __initdata memory_end_set;
91 unsigned long __initdata memory_end;
92
93 /* An array with a pointer to the lowcore of every CPU. */
94 struct _lowcore *lowcore_ptr[NR_CPUS];
95 EXPORT_SYMBOL(lowcore_ptr);
96
97 /*
98  * This is set up by the setup-routine at boot-time
99  * for S390 need to find out, what we have to setup
100  * using address 0x10400 ...
101  */
102
103 #include <asm/setup.h>
104
105 static struct resource code_resource = {
106         .name  = "Kernel code",
107         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
108 };
109
110 static struct resource data_resource = {
111         .name = "Kernel data",
112         .flags = IORESOURCE_BUSY | IORESOURCE_MEM,
113 };
114
115 /*
116  * condev= and conmode= setup parameter.
117  */
118
119 static int __init condev_setup(char *str)
120 {
121         int vdev;
122
123         vdev = simple_strtoul(str, &str, 0);
124         if (vdev >= 0 && vdev < 65536) {
125                 console_devno = vdev;
126                 console_irq = -1;
127         }
128         return 1;
129 }
130
131 __setup("condev=", condev_setup);
132
133 static void __init set_preferred_console(void)
134 {
135         if (MACHINE_IS_KVM)
136                 add_preferred_console("hvc", 0, NULL);
137         else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
138                 add_preferred_console("ttyS", 0, NULL);
139         else if (CONSOLE_IS_3270)
140                 add_preferred_console("tty3270", 0, NULL);
141 }
142
143 static int __init conmode_setup(char *str)
144 {
145 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
146         if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
147                 SET_CONSOLE_SCLP;
148 #endif
149 #if defined(CONFIG_TN3215_CONSOLE)
150         if (strncmp(str, "3215", 5) == 0)
151                 SET_CONSOLE_3215;
152 #endif
153 #if defined(CONFIG_TN3270_CONSOLE)
154         if (strncmp(str, "3270", 5) == 0)
155                 SET_CONSOLE_3270;
156 #endif
157         set_preferred_console();
158         return 1;
159 }
160
161 __setup("conmode=", conmode_setup);
162
163 static void __init conmode_default(void)
164 {
165         char query_buffer[1024];
166         char *ptr;
167
168         if (MACHINE_IS_VM) {
169                 cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
170                 console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
171                 ptr = strstr(query_buffer, "SUBCHANNEL =");
172                 console_irq = simple_strtoul(ptr + 13, NULL, 16);
173                 cpcmd("QUERY TERM", query_buffer, 1024, NULL);
174                 ptr = strstr(query_buffer, "CONMODE");
175                 /*
176                  * Set the conmode to 3215 so that the device recognition 
177                  * will set the cu_type of the console to 3215. If the
178                  * conmode is 3270 and we don't set it back then both
179                  * 3215 and the 3270 driver will try to access the console
180                  * device (3215 as console and 3270 as normal tty).
181                  */
182                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
183                 if (ptr == NULL) {
184 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
185                         SET_CONSOLE_SCLP;
186 #endif
187                         return;
188                 }
189                 if (strncmp(ptr + 8, "3270", 4) == 0) {
190 #if defined(CONFIG_TN3270_CONSOLE)
191                         SET_CONSOLE_3270;
192 #elif defined(CONFIG_TN3215_CONSOLE)
193                         SET_CONSOLE_3215;
194 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
195                         SET_CONSOLE_SCLP;
196 #endif
197                 } else if (strncmp(ptr + 8, "3215", 4) == 0) {
198 #if defined(CONFIG_TN3215_CONSOLE)
199                         SET_CONSOLE_3215;
200 #elif defined(CONFIG_TN3270_CONSOLE)
201                         SET_CONSOLE_3270;
202 #elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
203                         SET_CONSOLE_SCLP;
204 #endif
205                 }
206         } else {
207 #if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
208                 SET_CONSOLE_SCLP;
209 #endif
210         }
211 }
212
213 #ifdef CONFIG_ZFCPDUMP
214 static void __init setup_zfcpdump(unsigned int console_devno)
215 {
216         static char str[41];
217
218         if (ipl_info.type != IPL_TYPE_FCP_DUMP)
219                 return;
220         if (console_devno != -1)
221                 sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
222                         ipl_info.data.fcp.dev_id.devno, console_devno);
223         else
224                 sprintf(str, " cio_ignore=all,!0.0.%04x",
225                         ipl_info.data.fcp.dev_id.devno);
226         strcat(boot_command_line, str);
227         console_loglevel = 2;
228 }
229 #else
230 static inline void setup_zfcpdump(unsigned int console_devno) {}
231 #endif /* CONFIG_ZFCPDUMP */
232
233  /*
234  * Reboot, halt and power_off stubs. They just call _machine_restart,
235  * _machine_halt or _machine_power_off. 
236  */
237
238 void machine_restart(char *command)
239 {
240         if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
241                 /*
242                  * Only unblank the console if we are called in enabled
243                  * context or a bust_spinlocks cleared the way for us.
244                  */
245                 console_unblank();
246         _machine_restart(command);
247 }
248
249 void machine_halt(void)
250 {
251         if (!in_interrupt() || oops_in_progress)
252                 /*
253                  * Only unblank the console if we are called in enabled
254                  * context or a bust_spinlocks cleared the way for us.
255                  */
256                 console_unblank();
257         _machine_halt();
258 }
259
260 void machine_power_off(void)
261 {
262         if (!in_interrupt() || oops_in_progress)
263                 /*
264                  * Only unblank the console if we are called in enabled
265                  * context or a bust_spinlocks cleared the way for us.
266                  */
267                 console_unblank();
268         _machine_power_off();
269 }
270
271 /*
272  * Dummy power off function.
273  */
274 void (*pm_power_off)(void) = machine_power_off;
275
276 static int __init early_parse_mem(char *p)
277 {
278         memory_end = memparse(p, &p);
279         memory_end_set = 1;
280         return 0;
281 }
282 early_param("mem", early_parse_mem);
283
284 unsigned int user_mode = HOME_SPACE_MODE;
285 EXPORT_SYMBOL_GPL(user_mode);
286
287 static int set_amode_and_uaccess(unsigned long user_amode,
288                                  unsigned long user32_amode)
289 {
290         psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
291                         PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
292                         PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
293 #ifdef CONFIG_COMPAT
294         psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
295                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
296                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
297         psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
298                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
299                           PSW32_MASK_PSTATE;
300 #endif
301         psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
302                           PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
303
304         if (MACHINE_HAS_MVCOS) {
305                 memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
306                 return 1;
307         } else {
308                 memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
309                 return 0;
310         }
311 }
312
313 /*
314  * Switch kernel/user addressing modes?
315  */
316 static int __init early_parse_switch_amode(char *p)
317 {
318         if (user_mode != SECONDARY_SPACE_MODE)
319                 user_mode = PRIMARY_SPACE_MODE;
320         return 0;
321 }
322 early_param("switch_amode", early_parse_switch_amode);
323
324 static int __init early_parse_user_mode(char *p)
325 {
326         if (p && strcmp(p, "primary") == 0)
327                 user_mode = PRIMARY_SPACE_MODE;
328 #ifdef CONFIG_S390_EXEC_PROTECT
329         else if (p && strcmp(p, "secondary") == 0)
330                 user_mode = SECONDARY_SPACE_MODE;
331 #endif
332         else if (!p || strcmp(p, "home") == 0)
333                 user_mode = HOME_SPACE_MODE;
334         else
335                 return 1;
336         return 0;
337 }
338 early_param("user_mode", early_parse_user_mode);
339
340 #ifdef CONFIG_S390_EXEC_PROTECT
341 /*
342  * Enable execute protection?
343  */
344 static int __init early_parse_noexec(char *p)
345 {
346         if (!strncmp(p, "off", 3))
347                 return 0;
348         user_mode = SECONDARY_SPACE_MODE;
349         return 0;
350 }
351 early_param("noexec", early_parse_noexec);
352 #endif /* CONFIG_S390_EXEC_PROTECT */
353
354 static void setup_addressing_mode(void)
355 {
356         if (user_mode == SECONDARY_SPACE_MODE) {
357                 if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
358                                           PSW32_ASC_SECONDARY))
359                         pr_info("Execute protection active, "
360                                 "mvcos available\n");
361                 else
362                         pr_info("Execute protection active, "
363                                 "mvcos not available\n");
364         } else if (user_mode == PRIMARY_SPACE_MODE) {
365                 if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
366                         pr_info("Address spaces switched, "
367                                 "mvcos available\n");
368                 else
369                         pr_info("Address spaces switched, "
370                                 "mvcos not available\n");
371         }
372 }
373
374 static void __init
375 setup_lowcore(void)
376 {
377         struct _lowcore *lc;
378
379         /*
380          * Setup lowcore for boot cpu
381          */
382         BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
383         lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
384         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
385         lc->restart_psw.addr =
386                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
387         if (user_mode != HOME_SPACE_MODE)
388                 lc->restart_psw.mask |= PSW_ASC_HOME;
389         lc->external_new_psw.mask = psw_kernel_bits;
390         lc->external_new_psw.addr =
391                 PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
392         lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
393         lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
394         lc->program_new_psw.mask = psw_kernel_bits;
395         lc->program_new_psw.addr =
396                 PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
397         lc->mcck_new_psw.mask =
398                 psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
399         lc->mcck_new_psw.addr =
400                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
401         lc->io_new_psw.mask = psw_kernel_bits;
402         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
403         lc->clock_comparator = -1ULL;
404         lc->cmf_hpp = -1ULL;
405         lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
406         lc->async_stack = (unsigned long)
407                 __alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
408         lc->panic_stack = (unsigned long)
409                 __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
410         lc->current_task = (unsigned long) init_thread_union.thread_info.task;
411         lc->thread_info = (unsigned long) &init_thread_union;
412         lc->machine_flags = S390_lowcore.machine_flags;
413 #ifndef CONFIG_64BIT
414         if (MACHINE_HAS_IEEE) {
415                 lc->extended_save_area_addr = (__u32)
416                         __alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
417                 /* enable extended save area */
418                 __ctl_set_bit(14, 29);
419         }
420 #else
421         lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
422 #endif
423         lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
424         lc->async_enter_timer = S390_lowcore.async_enter_timer;
425         lc->exit_timer = S390_lowcore.exit_timer;
426         lc->user_timer = S390_lowcore.user_timer;
427         lc->system_timer = S390_lowcore.system_timer;
428         lc->steal_timer = S390_lowcore.steal_timer;
429         lc->last_update_timer = S390_lowcore.last_update_timer;
430         lc->last_update_clock = S390_lowcore.last_update_clock;
431         lc->ftrace_func = S390_lowcore.ftrace_func;
432         set_prefix((u32)(unsigned long) lc);
433         lowcore_ptr[0] = 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 #ifdef CONFIG_ZFCPDUMP
511         if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
512                 memory_end = ZFCPDUMP_HSA_SIZE;
513                 memory_end_set = 1;
514         }
515 #endif
516         memory_size = 0;
517         memory_end &= PAGE_MASK;
518
519         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
520         memory_end = min(max_mem, memory_end);
521
522         /*
523          * Make sure all chunks are MAX_ORDER aligned so we don't need the
524          * extra checks that HOLES_IN_ZONE would require.
525          */
526         for (i = 0; i < MEMORY_CHUNKS; i++) {
527                 unsigned long start, end;
528                 struct mem_chunk *chunk;
529                 unsigned long align;
530
531                 chunk = &memory_chunk[i];
532                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
533                 start = (chunk->addr + align - 1) & ~(align - 1);
534                 end = (chunk->addr + chunk->size) & ~(align - 1);
535                 if (start >= end)
536                         memset(chunk, 0, sizeof(*chunk));
537                 else {
538                         chunk->addr = start;
539                         chunk->size = end - start;
540                 }
541         }
542
543         for (i = 0; i < MEMORY_CHUNKS; i++) {
544                 struct mem_chunk *chunk = &memory_chunk[i];
545
546                 real_memory_size = max(real_memory_size,
547                                        chunk->addr + chunk->size);
548                 if (chunk->addr >= max_mem) {
549                         memset(chunk, 0, sizeof(*chunk));
550                         continue;
551                 }
552                 if (chunk->addr + chunk->size > max_mem)
553                         chunk->size = max_mem - chunk->addr;
554                 memory_size = max(memory_size, chunk->addr + chunk->size);
555         }
556         if (!memory_end)
557                 memory_end = memory_size;
558 }
559
560 static void __init
561 setup_memory(void)
562 {
563         unsigned long bootmap_size;
564         unsigned long start_pfn, end_pfn;
565         int i;
566
567         /*
568          * partially used pages are not usable - thus
569          * we are rounding upwards:
570          */
571         start_pfn = PFN_UP(__pa(&_end));
572         end_pfn = max_pfn = PFN_DOWN(memory_end);
573
574 #ifdef CONFIG_BLK_DEV_INITRD
575         /*
576          * Move the initrd in case the bitmap of the bootmem allocater
577          * would overwrite it.
578          */
579
580         if (INITRD_START && INITRD_SIZE) {
581                 unsigned long bmap_size;
582                 unsigned long start;
583
584                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
585                 bmap_size = PFN_PHYS(bmap_size);
586
587                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
588                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
589
590                         if (start + INITRD_SIZE > memory_end) {
591                                 pr_err("initrd extends beyond end of "
592                                        "memory (0x%08lx > 0x%08lx) "
593                                        "disabling initrd\n",
594                                        start + INITRD_SIZE, memory_end);
595                                 INITRD_START = INITRD_SIZE = 0;
596                         } else {
597                                 pr_info("Moving initrd (0x%08lx -> "
598                                         "0x%08lx, size: %ld)\n",
599                                         INITRD_START, start, INITRD_SIZE);
600                                 memmove((void *) start, (void *) INITRD_START,
601                                         INITRD_SIZE);
602                                 INITRD_START = start;
603                         }
604                 }
605         }
606 #endif
607
608         /*
609          * Initialize the boot-time allocator
610          */
611         bootmap_size = init_bootmem(start_pfn, end_pfn);
612
613         /*
614          * Register RAM areas with the bootmem allocator.
615          */
616
617         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
618                 unsigned long start_chunk, end_chunk, pfn;
619
620                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
621                         continue;
622                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
623                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
624                 end_chunk = min(end_chunk, end_pfn);
625                 if (start_chunk >= end_chunk)
626                         continue;
627                 add_active_range(0, start_chunk, end_chunk);
628                 pfn = max(start_chunk, start_pfn);
629                 for (; pfn < end_chunk; pfn++)
630                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
631         }
632
633         psw_set_key(PAGE_DEFAULT_KEY);
634
635         free_bootmem_with_active_regions(0, max_pfn);
636
637         /*
638          * Reserve memory used for lowcore/command line/kernel image.
639          */
640         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
641         reserve_bootmem((unsigned long)_stext,
642                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
643                         BOOTMEM_DEFAULT);
644         /*
645          * Reserve the bootmem bitmap itself as well. We do this in two
646          * steps (first step was init_bootmem()) because this catches
647          * the (very unlikely) case of us accidentally initializing the
648          * bootmem allocator with an invalid RAM area.
649          */
650         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
651                         BOOTMEM_DEFAULT);
652
653 #ifdef CONFIG_BLK_DEV_INITRD
654         if (INITRD_START && INITRD_SIZE) {
655                 if (INITRD_START + INITRD_SIZE <= memory_end) {
656                         reserve_bootmem(INITRD_START, INITRD_SIZE,
657                                         BOOTMEM_DEFAULT);
658                         initrd_start = INITRD_START;
659                         initrd_end = initrd_start + INITRD_SIZE;
660                 } else {
661                         pr_err("initrd extends beyond end of "
662                                "memory (0x%08lx > 0x%08lx) "
663                                "disabling initrd\n",
664                                initrd_start + INITRD_SIZE, memory_end);
665                         initrd_start = initrd_end = 0;
666                 }
667         }
668 #endif
669 }
670
671 /*
672  * Setup hardware capabilities.
673  */
674 static void __init setup_hwcaps(void)
675 {
676         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
677         unsigned long long facility_list_extended;
678         unsigned int facility_list;
679         struct cpuid cpu_id;
680         int i;
681
682         facility_list = stfl();
683         /*
684          * The store facility list bits numbers as found in the principles
685          * of operation are numbered with bit 1UL<<31 as number 0 to
686          * bit 1UL<<0 as number 31.
687          *   Bit 0: instructions named N3, "backported" to esa-mode
688          *   Bit 2: z/Architecture mode is active
689          *   Bit 7: the store-facility-list-extended facility is installed
690          *   Bit 17: the message-security assist is installed
691          *   Bit 19: the long-displacement facility is installed
692          *   Bit 21: the extended-immediate facility is installed
693          *   Bit 22: extended-translation facility 3 is installed
694          *   Bit 30: extended-translation facility 3 enhancement facility
695          * These get translated to:
696          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
697          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
698          *   HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
699          *   HWCAP_S390_ETF3EH bit 8 (22 && 30).
700          */
701         for (i = 0; i < 6; i++)
702                 if (facility_list & (1UL << (31 - stfl_bits[i])))
703                         elf_hwcap |= 1UL << i;
704
705         if ((facility_list & (1UL << (31 - 22)))
706             && (facility_list & (1UL << (31 - 30))))
707                 elf_hwcap |= HWCAP_S390_ETF3EH;
708
709         /*
710          * Check for additional facilities with store-facility-list-extended.
711          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
712          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
713          * as stored by stfl, bits 32-xxx contain additional facilities.
714          * How many facility words are stored depends on the number of
715          * doublewords passed to the instruction. The additional facilites
716          * are:
717          *   Bit 42: decimal floating point facility is installed
718          *   Bit 44: perform floating point operation facility is installed
719          * translated to:
720          *   HWCAP_S390_DFP bit 6 (42 && 44).
721          */
722         if ((elf_hwcap & (1UL << 2)) &&
723             __stfle(&facility_list_extended, 1) > 0) {
724                 if ((facility_list_extended & (1ULL << (63 - 42)))
725                     && (facility_list_extended & (1ULL << (63 - 44))))
726                         elf_hwcap |= HWCAP_S390_DFP;
727         }
728
729         /*
730          * Huge page support HWCAP_S390_HPAGE is bit 7.
731          */
732         if (MACHINE_HAS_HPAGE)
733                 elf_hwcap |= HWCAP_S390_HPAGE;
734
735         /*
736          * 64-bit register support for 31-bit processes
737          * HWCAP_S390_HIGH_GPRS is bit 9.
738          */
739         elf_hwcap |= HWCAP_S390_HIGH_GPRS;
740
741         get_cpu_id(&cpu_id);
742         switch (cpu_id.machine) {
743         case 0x9672:
744 #if !defined(CONFIG_64BIT)
745         default:        /* Use "g5" as default for 31 bit kernels. */
746 #endif
747                 strcpy(elf_platform, "g5");
748                 break;
749         case 0x2064:
750         case 0x2066:
751 #if defined(CONFIG_64BIT)
752         default:        /* Use "z900" as default for 64 bit kernels. */
753 #endif
754                 strcpy(elf_platform, "z900");
755                 break;
756         case 0x2084:
757         case 0x2086:
758                 strcpy(elf_platform, "z990");
759                 break;
760         case 0x2094:
761         case 0x2096:
762                 strcpy(elf_platform, "z9-109");
763                 break;
764         case 0x2097:
765         case 0x2098:
766                 strcpy(elf_platform, "z10");
767                 break;
768         }
769 }
770
771 /*
772  * Setup function called from init/main.c just after the banner
773  * was printed.
774  */
775
776 void __init
777 setup_arch(char **cmdline_p)
778 {
779         /*
780          * print what head.S has found out about the machine
781          */
782 #ifndef CONFIG_64BIT
783         if (MACHINE_IS_VM)
784                 pr_info("Linux is running as a z/VM "
785                         "guest operating system in 31-bit mode\n");
786         else if (MACHINE_IS_LPAR)
787                 pr_info("Linux is running natively in 31-bit mode\n");
788         if (MACHINE_HAS_IEEE)
789                 pr_info("The hardware system has IEEE compatible "
790                         "floating point units\n");
791         else
792                 pr_info("The hardware system has no IEEE compatible "
793                         "floating point units\n");
794 #else /* CONFIG_64BIT */
795         if (MACHINE_IS_VM)
796                 pr_info("Linux is running as a z/VM "
797                         "guest operating system in 64-bit mode\n");
798         else if (MACHINE_IS_KVM)
799                 pr_info("Linux is running under KVM in 64-bit mode\n");
800         else if (MACHINE_IS_LPAR)
801                 pr_info("Linux is running natively in 64-bit mode\n");
802 #endif /* CONFIG_64BIT */
803
804         /* Have one command line that is parsed and saved in /proc/cmdline */
805         /* boot_command_line has been already set up in early.c */
806         *cmdline_p = boot_command_line;
807
808         ROOT_DEV = Root_RAM0;
809
810         init_mm.start_code = PAGE_OFFSET;
811         init_mm.end_code = (unsigned long) &_etext;
812         init_mm.end_data = (unsigned long) &_edata;
813         init_mm.brk = (unsigned long) &_end;
814
815         if (MACHINE_HAS_MVCOS)
816                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
817         else
818                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
819
820         parse_early_param();
821
822         setup_ipl();
823         setup_memory_end();
824         setup_addressing_mode();
825         setup_memory();
826         setup_resources();
827         setup_lowcore();
828
829         cpu_init();
830         s390_init_cpu_topology();
831
832         /*
833          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
834          */
835         setup_hwcaps();
836
837         /*
838          * Create kernel page tables and switch to virtual addressing.
839          */
840         paging_init();
841
842         /* Setup default console */
843         conmode_default();
844         set_preferred_console();
845
846         /* Setup zfcpdump support */
847         setup_zfcpdump(console_devno);
848 }