Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[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 #endif
431         set_prefix((u32)(unsigned long) lc);
432 }
433
434 static void __init
435 setup_resources(void)
436 {
437         struct resource *res, *sub_res;
438         int i;
439
440         code_resource.start = (unsigned long) &_text;
441         code_resource.end = (unsigned long) &_etext - 1;
442         data_resource.start = (unsigned long) &_etext;
443         data_resource.end = (unsigned long) &_edata - 1;
444
445         for (i = 0; i < MEMORY_CHUNKS; i++) {
446                 if (!memory_chunk[i].size)
447                         continue;
448                 res = alloc_bootmem_low(sizeof(struct resource));
449                 res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
450                 switch (memory_chunk[i].type) {
451                 case CHUNK_READ_WRITE:
452                         res->name = "System RAM";
453                         break;
454                 case CHUNK_READ_ONLY:
455                         res->name = "System ROM";
456                         res->flags |= IORESOURCE_READONLY;
457                         break;
458                 default:
459                         res->name = "reserved";
460                 }
461                 res->start = memory_chunk[i].addr;
462                 res->end = memory_chunk[i].addr +  memory_chunk[i].size - 1;
463                 request_resource(&iomem_resource, res);
464
465                 if (code_resource.start >= res->start  &&
466                         code_resource.start <= res->end &&
467                         code_resource.end > res->end) {
468                         sub_res = alloc_bootmem_low(sizeof(struct resource));
469                         memcpy(sub_res, &code_resource,
470                                 sizeof(struct resource));
471                         sub_res->end = res->end;
472                         code_resource.start = res->end + 1;
473                         request_resource(res, sub_res);
474                 }
475
476                 if (code_resource.start >= res->start &&
477                         code_resource.start <= res->end &&
478                         code_resource.end <= res->end)
479                         request_resource(res, &code_resource);
480
481                 if (data_resource.start >= res->start &&
482                         data_resource.start <= res->end &&
483                         data_resource.end > res->end) {
484                         sub_res = alloc_bootmem_low(sizeof(struct resource));
485                         memcpy(sub_res, &data_resource,
486                                 sizeof(struct resource));
487                         sub_res->end = res->end;
488                         data_resource.start = res->end + 1;
489                         request_resource(res, sub_res);
490                 }
491
492                 if (data_resource.start >= res->start &&
493                         data_resource.start <= res->end &&
494                         data_resource.end <= res->end)
495                         request_resource(res, &data_resource);
496         }
497 }
498
499 unsigned long real_memory_size;
500 EXPORT_SYMBOL_GPL(real_memory_size);
501
502 static void __init setup_memory_end(void)
503 {
504         unsigned long memory_size;
505         unsigned long max_mem;
506         int i;
507
508 #if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
509         if (ipl_info.type == IPL_TYPE_FCP_DUMP)
510                 memory_end = ZFCPDUMP_HSA_SIZE;
511 #endif
512         memory_size = 0;
513         memory_end &= PAGE_MASK;
514
515         max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
516         memory_end = min(max_mem, memory_end);
517
518         /*
519          * Make sure all chunks are MAX_ORDER aligned so we don't need the
520          * extra checks that HOLES_IN_ZONE would require.
521          */
522         for (i = 0; i < MEMORY_CHUNKS; i++) {
523                 unsigned long start, end;
524                 struct mem_chunk *chunk;
525                 unsigned long align;
526
527                 chunk = &memory_chunk[i];
528                 align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
529                 start = (chunk->addr + align - 1) & ~(align - 1);
530                 end = (chunk->addr + chunk->size) & ~(align - 1);
531                 if (start >= end)
532                         memset(chunk, 0, sizeof(*chunk));
533                 else {
534                         chunk->addr = start;
535                         chunk->size = end - start;
536                 }
537         }
538
539         for (i = 0; i < MEMORY_CHUNKS; i++) {
540                 struct mem_chunk *chunk = &memory_chunk[i];
541
542                 real_memory_size = max(real_memory_size,
543                                        chunk->addr + chunk->size);
544                 if (chunk->addr >= max_mem) {
545                         memset(chunk, 0, sizeof(*chunk));
546                         continue;
547                 }
548                 if (chunk->addr + chunk->size > max_mem)
549                         chunk->size = max_mem - chunk->addr;
550                 memory_size = max(memory_size, chunk->addr + chunk->size);
551         }
552         if (!memory_end)
553                 memory_end = memory_size;
554 }
555
556 static void __init
557 setup_memory(void)
558 {
559         unsigned long bootmap_size;
560         unsigned long start_pfn, end_pfn;
561         int i;
562
563         /*
564          * partially used pages are not usable - thus
565          * we are rounding upwards:
566          */
567         start_pfn = PFN_UP(__pa(&_end));
568         end_pfn = max_pfn = PFN_DOWN(memory_end);
569
570 #ifdef CONFIG_BLK_DEV_INITRD
571         /*
572          * Move the initrd in case the bitmap of the bootmem allocater
573          * would overwrite it.
574          */
575
576         if (INITRD_START && INITRD_SIZE) {
577                 unsigned long bmap_size;
578                 unsigned long start;
579
580                 bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
581                 bmap_size = PFN_PHYS(bmap_size);
582
583                 if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
584                         start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
585
586                         if (start + INITRD_SIZE > memory_end) {
587                                 pr_err("initrd extends beyond end of "
588                                        "memory (0x%08lx > 0x%08lx) "
589                                        "disabling initrd\n",
590                                        start + INITRD_SIZE, memory_end);
591                                 INITRD_START = INITRD_SIZE = 0;
592                         } else {
593                                 pr_info("Moving initrd (0x%08lx -> "
594                                         "0x%08lx, size: %ld)\n",
595                                         INITRD_START, start, INITRD_SIZE);
596                                 memmove((void *) start, (void *) INITRD_START,
597                                         INITRD_SIZE);
598                                 INITRD_START = start;
599                         }
600                 }
601         }
602 #endif
603
604         /*
605          * Initialize the boot-time allocator
606          */
607         bootmap_size = init_bootmem(start_pfn, end_pfn);
608
609         /*
610          * Register RAM areas with the bootmem allocator.
611          */
612
613         for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
614                 unsigned long start_chunk, end_chunk, pfn;
615
616                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
617                         continue;
618                 start_chunk = PFN_DOWN(memory_chunk[i].addr);
619                 end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
620                 end_chunk = min(end_chunk, end_pfn);
621                 if (start_chunk >= end_chunk)
622                         continue;
623                 add_active_range(0, start_chunk, end_chunk);
624                 pfn = max(start_chunk, start_pfn);
625                 for (; pfn < end_chunk; pfn++)
626                         page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
627         }
628
629         psw_set_key(PAGE_DEFAULT_KEY);
630
631         free_bootmem_with_active_regions(0, max_pfn);
632
633         /*
634          * Reserve memory used for lowcore/command line/kernel image.
635          */
636         reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
637         reserve_bootmem((unsigned long)_stext,
638                         PFN_PHYS(start_pfn) - (unsigned long)_stext,
639                         BOOTMEM_DEFAULT);
640         /*
641          * Reserve the bootmem bitmap itself as well. We do this in two
642          * steps (first step was init_bootmem()) because this catches
643          * the (very unlikely) case of us accidentally initializing the
644          * bootmem allocator with an invalid RAM area.
645          */
646         reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
647                         BOOTMEM_DEFAULT);
648
649 #ifdef CONFIG_BLK_DEV_INITRD
650         if (INITRD_START && INITRD_SIZE) {
651                 if (INITRD_START + INITRD_SIZE <= memory_end) {
652                         reserve_bootmem(INITRD_START, INITRD_SIZE,
653                                         BOOTMEM_DEFAULT);
654                         initrd_start = INITRD_START;
655                         initrd_end = initrd_start + INITRD_SIZE;
656                 } else {
657                         pr_err("initrd extends beyond end of "
658                                "memory (0x%08lx > 0x%08lx) "
659                                "disabling initrd\n",
660                                initrd_start + INITRD_SIZE, memory_end);
661                         initrd_start = initrd_end = 0;
662                 }
663         }
664 #endif
665 }
666
667 /*
668  * Setup hardware capabilities.
669  */
670 static void __init setup_hwcaps(void)
671 {
672         static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
673         struct cpuinfo_S390 *cpuinfo = &S390_lowcore.cpu_data;
674         unsigned long long facility_list_extended;
675         unsigned int facility_list;
676         int i;
677
678         facility_list = stfl();
679         /*
680          * The store facility list bits numbers as found in the principles
681          * of operation are numbered with bit 1UL<<31 as number 0 to
682          * bit 1UL<<0 as number 31.
683          *   Bit 0: instructions named N3, "backported" to esa-mode
684          *   Bit 2: z/Architecture mode is active
685          *   Bit 7: the store-facility-list-extended facility is installed
686          *   Bit 17: the message-security assist is installed
687          *   Bit 19: the long-displacement facility is installed
688          *   Bit 21: the extended-immediate facility is installed
689          * These get translated to:
690          *   HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
691          *   HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
692          *   HWCAP_S390_LDISP bit 4, and HWCAP_S390_EIMM bit 5.
693          */
694         for (i = 0; i < 6; i++)
695                 if (facility_list & (1UL << (31 - stfl_bits[i])))
696                         elf_hwcap |= 1UL << i;
697
698         /*
699          * Check for additional facilities with store-facility-list-extended.
700          * stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
701          * and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
702          * as stored by stfl, bits 32-xxx contain additional facilities.
703          * How many facility words are stored depends on the number of
704          * doublewords passed to the instruction. The additional facilites
705          * are:
706          *   Bit 43: decimal floating point facility is installed
707          * translated to:
708          *   HWCAP_S390_DFP bit 6.
709          */
710         if ((elf_hwcap & (1UL << 2)) &&
711             __stfle(&facility_list_extended, 1) > 0) {
712                 if (facility_list_extended & (1ULL << (64 - 43)))
713                         elf_hwcap |= 1UL << 6;
714         }
715
716         if (MACHINE_HAS_HPAGE)
717                 elf_hwcap |= 1UL << 7;
718
719         switch (cpuinfo->cpu_id.machine) {
720         case 0x9672:
721 #if !defined(CONFIG_64BIT)
722         default:        /* Use "g5" as default for 31 bit kernels. */
723 #endif
724                 strcpy(elf_platform, "g5");
725                 break;
726         case 0x2064:
727         case 0x2066:
728 #if defined(CONFIG_64BIT)
729         default:        /* Use "z900" as default for 64 bit kernels. */
730 #endif
731                 strcpy(elf_platform, "z900");
732                 break;
733         case 0x2084:
734         case 0x2086:
735                 strcpy(elf_platform, "z990");
736                 break;
737         case 0x2094:
738         case 0x2096:
739                 strcpy(elf_platform, "z9-109");
740                 break;
741         case 0x2097:
742         case 0x2098:
743                 strcpy(elf_platform, "z10");
744                 break;
745         }
746 }
747
748 /*
749  * Setup function called from init/main.c just after the banner
750  * was printed.
751  */
752
753 void __init
754 setup_arch(char **cmdline_p)
755 {
756         /* set up preferred console */
757         add_preferred_console("ttyS", 0, NULL);
758
759         /*
760          * print what head.S has found out about the machine
761          */
762 #ifndef CONFIG_64BIT
763         if (MACHINE_IS_VM)
764                 pr_info("Linux is running as a z/VM "
765                         "guest operating system in 31-bit mode\n");
766         else
767                 pr_info("Linux is running natively in 31-bit mode\n");
768         if (MACHINE_HAS_IEEE)
769                 pr_info("The hardware system has IEEE compatible "
770                         "floating point units\n");
771         else
772                 pr_info("The hardware system has no IEEE compatible "
773                         "floating point units\n");
774 #else /* CONFIG_64BIT */
775         if (MACHINE_IS_VM)
776                 pr_info("Linux is running as a z/VM "
777                         "guest operating system in 64-bit mode\n");
778         else if (MACHINE_IS_KVM) {
779                 pr_info("Linux is running under KVM in 64-bit mode\n");
780                 add_preferred_console("hvc", 0, NULL);
781                 s390_virtio_console_init();
782         } else
783                 pr_info("Linux is running natively in 64-bit mode\n");
784 #endif /* CONFIG_64BIT */
785
786         /* Have one command line that is parsed and saved in /proc/cmdline */
787         /* boot_command_line has been already set up in early.c */
788         *cmdline_p = boot_command_line;
789
790         ROOT_DEV = Root_RAM0;
791
792         init_mm.start_code = PAGE_OFFSET;
793         init_mm.end_code = (unsigned long) &_etext;
794         init_mm.end_data = (unsigned long) &_edata;
795         init_mm.brk = (unsigned long) &_end;
796
797         if (MACHINE_HAS_MVCOS)
798                 memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
799         else
800                 memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
801
802         parse_early_param();
803
804         setup_ipl();
805         setup_memory_end();
806         setup_addressing_mode();
807         setup_memory();
808         setup_resources();
809         setup_lowcore();
810
811         cpu_init();
812         __cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
813         s390_init_cpu_topology();
814
815         /*
816          * Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
817          */
818         setup_hwcaps();
819
820         /*
821          * Create kernel page tables and switch to virtual addressing.
822          */
823         paging_init();
824
825         /* Setup default console */
826         conmode_default();
827
828         /* Setup zfcpdump support */
829         setup_zfcpdump(console_devno);
830 }