[CPUFREQ] If max_freq got reduced (e.g. by _PPC) a write to sysfs scaling_governor...
[linux-2.6] / drivers / acpi / tables.c
1 /*
2  *  acpi_tables.c - ACPI Boot-Time Table Parsing
3  *
4  *  Copyright (C) 2001 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
5  *
6  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; either version 2 of the License, or
11  *  (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, write to the Free Software
20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  *
22  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23  *
24  */
25
26 #include <linux/config.h>
27 #include <linux/init.h>
28 #include <linux/kernel.h>
29 #include <linux/sched.h>
30 #include <linux/smp.h>
31 #include <linux/string.h>
32 #include <linux/types.h>
33 #include <linux/irq.h>
34 #include <linux/errno.h>
35 #include <linux/acpi.h>
36 #include <linux/bootmem.h>
37
38 #define PREFIX                  "ACPI: "
39
40 #define ACPI_MAX_TABLES         128
41
42 static char *acpi_table_signatures[ACPI_TABLE_COUNT] = {
43         [ACPI_TABLE_UNKNOWN] = "????",
44         [ACPI_APIC] = "APIC",
45         [ACPI_BOOT] = "BOOT",
46         [ACPI_DBGP] = "DBGP",
47         [ACPI_DSDT] = "DSDT",
48         [ACPI_ECDT] = "ECDT",
49         [ACPI_ETDT] = "ETDT",
50         [ACPI_FADT] = "FACP",
51         [ACPI_FACS] = "FACS",
52         [ACPI_OEMX] = "OEM",
53         [ACPI_PSDT] = "PSDT",
54         [ACPI_SBST] = "SBST",
55         [ACPI_SLIT] = "SLIT",
56         [ACPI_SPCR] = "SPCR",
57         [ACPI_SRAT] = "SRAT",
58         [ACPI_SSDT] = "SSDT",
59         [ACPI_SPMI] = "SPMI",
60         [ACPI_HPET] = "HPET",
61         [ACPI_MCFG] = "MCFG",
62 };
63
64 static char *mps_inti_flags_polarity[] = { "dfl", "high", "res", "low" };
65 static char *mps_inti_flags_trigger[] = { "dfl", "edge", "res", "level" };
66
67 /* System Description Table (RSDT/XSDT) */
68 struct acpi_table_sdt {
69         unsigned long pa;
70         enum acpi_table_id id;
71         unsigned long size;
72 } __attribute__ ((packed));
73
74 static unsigned long sdt_pa;    /* Physical Address */
75 static unsigned long sdt_count; /* Table count */
76
77 static struct acpi_table_sdt sdt_entry[ACPI_MAX_TABLES] __initdata;
78
79 void acpi_table_print(struct acpi_table_header *header, unsigned long phys_addr)
80 {
81         char *name = NULL;
82
83         if (!header)
84                 return;
85
86         /* Some table signatures aren't good table names */
87
88         if (!strncmp((char *)&header->signature,
89                      acpi_table_signatures[ACPI_APIC],
90                      sizeof(header->signature))) {
91                 name = "MADT";
92         } else if (!strncmp((char *)&header->signature,
93                             acpi_table_signatures[ACPI_FADT],
94                             sizeof(header->signature))) {
95                 name = "FADT";
96         } else
97                 name = header->signature;
98
99         printk(KERN_DEBUG PREFIX
100                "%.4s (v%3.3d %6.6s %8.8s 0x%08x %.4s 0x%08x) @ 0x%p\n", name,
101                header->revision, header->oem_id, header->oem_table_id,
102                header->oem_revision, header->asl_compiler_id,
103                header->asl_compiler_revision, (void *)phys_addr);
104 }
105
106 void acpi_table_print_madt_entry(acpi_table_entry_header * header)
107 {
108         if (!header)
109                 return;
110
111         switch (header->type) {
112
113         case ACPI_MADT_LAPIC:
114                 {
115                         struct acpi_table_lapic *p =
116                             (struct acpi_table_lapic *)header;
117                         printk(KERN_INFO PREFIX
118                                "LAPIC (acpi_id[0x%02x] lapic_id[0x%02x] %s)\n",
119                                p->acpi_id, p->id,
120                                p->flags.enabled ? "enabled" : "disabled");
121                 }
122                 break;
123
124         case ACPI_MADT_IOAPIC:
125                 {
126                         struct acpi_table_ioapic *p =
127                             (struct acpi_table_ioapic *)header;
128                         printk(KERN_INFO PREFIX
129                                "IOAPIC (id[0x%02x] address[0x%08x] gsi_base[%d])\n",
130                                p->id, p->address, p->global_irq_base);
131                 }
132                 break;
133
134         case ACPI_MADT_INT_SRC_OVR:
135                 {
136                         struct acpi_table_int_src_ovr *p =
137                             (struct acpi_table_int_src_ovr *)header;
138                         printk(KERN_INFO PREFIX
139                                "INT_SRC_OVR (bus %d bus_irq %d global_irq %d %s %s)\n",
140                                p->bus, p->bus_irq, p->global_irq,
141                                mps_inti_flags_polarity[p->flags.polarity],
142                                mps_inti_flags_trigger[p->flags.trigger]);
143                         if (p->flags.reserved)
144                                 printk(KERN_INFO PREFIX
145                                        "INT_SRC_OVR unexpected reserved flags: 0x%x\n",
146                                        p->flags.reserved);
147
148                 }
149                 break;
150
151         case ACPI_MADT_NMI_SRC:
152                 {
153                         struct acpi_table_nmi_src *p =
154                             (struct acpi_table_nmi_src *)header;
155                         printk(KERN_INFO PREFIX
156                                "NMI_SRC (%s %s global_irq %d)\n",
157                                mps_inti_flags_polarity[p->flags.polarity],
158                                mps_inti_flags_trigger[p->flags.trigger],
159                                p->global_irq);
160                 }
161                 break;
162
163         case ACPI_MADT_LAPIC_NMI:
164                 {
165                         struct acpi_table_lapic_nmi *p =
166                             (struct acpi_table_lapic_nmi *)header;
167                         printk(KERN_INFO PREFIX
168                                "LAPIC_NMI (acpi_id[0x%02x] %s %s lint[0x%x])\n",
169                                p->acpi_id,
170                                mps_inti_flags_polarity[p->flags.polarity],
171                                mps_inti_flags_trigger[p->flags.trigger],
172                                p->lint);
173                 }
174                 break;
175
176         case ACPI_MADT_LAPIC_ADDR_OVR:
177                 {
178                         struct acpi_table_lapic_addr_ovr *p =
179                             (struct acpi_table_lapic_addr_ovr *)header;
180                         printk(KERN_INFO PREFIX
181                                "LAPIC_ADDR_OVR (address[%p])\n",
182                                (void *)(unsigned long)p->address);
183                 }
184                 break;
185
186         case ACPI_MADT_IOSAPIC:
187                 {
188                         struct acpi_table_iosapic *p =
189                             (struct acpi_table_iosapic *)header;
190                         printk(KERN_INFO PREFIX
191                                "IOSAPIC (id[0x%x] address[%p] gsi_base[%d])\n",
192                                p->id, (void *)(unsigned long)p->address,
193                                p->global_irq_base);
194                 }
195                 break;
196
197         case ACPI_MADT_LSAPIC:
198                 {
199                         struct acpi_table_lsapic *p =
200                             (struct acpi_table_lsapic *)header;
201                         printk(KERN_INFO PREFIX
202                                "LSAPIC (acpi_id[0x%02x] lsapic_id[0x%02x] lsapic_eid[0x%02x] %s)\n",
203                                p->acpi_id, p->id, p->eid,
204                                p->flags.enabled ? "enabled" : "disabled");
205                 }
206                 break;
207
208         case ACPI_MADT_PLAT_INT_SRC:
209                 {
210                         struct acpi_table_plat_int_src *p =
211                             (struct acpi_table_plat_int_src *)header;
212                         printk(KERN_INFO PREFIX
213                                "PLAT_INT_SRC (%s %s type[0x%x] id[0x%04x] eid[0x%x] iosapic_vector[0x%x] global_irq[0x%x]\n",
214                                mps_inti_flags_polarity[p->flags.polarity],
215                                mps_inti_flags_trigger[p->flags.trigger],
216                                p->type, p->id, p->eid, p->iosapic_vector,
217                                p->global_irq);
218                 }
219                 break;
220
221         default:
222                 printk(KERN_WARNING PREFIX
223                        "Found unsupported MADT entry (type = 0x%x)\n",
224                        header->type);
225                 break;
226         }
227 }
228
229 static int
230 acpi_table_compute_checksum(void *table_pointer, unsigned long length)
231 {
232         u8 *p = (u8 *) table_pointer;
233         unsigned long remains = length;
234         unsigned long sum = 0;
235
236         if (!p || !length)
237                 return -EINVAL;
238
239         while (remains--)
240                 sum += *p++;
241
242         return (sum & 0xFF);
243 }
244
245 /*
246  * acpi_get_table_header_early()
247  * for acpi_blacklisted(), acpi_table_get_sdt()
248  */
249 int __init
250 acpi_get_table_header_early(enum acpi_table_id id,
251                             struct acpi_table_header **header)
252 {
253         unsigned int i;
254         enum acpi_table_id temp_id;
255
256         /* DSDT is different from the rest */
257         if (id == ACPI_DSDT)
258                 temp_id = ACPI_FADT;
259         else
260                 temp_id = id;
261
262         /* Locate the table. */
263
264         for (i = 0; i < sdt_count; i++) {
265                 if (sdt_entry[i].id != temp_id)
266                         continue;
267                 *header = (void *)
268                     __acpi_map_table(sdt_entry[i].pa, sdt_entry[i].size);
269                 if (!*header) {
270                         printk(KERN_WARNING PREFIX "Unable to map %s\n",
271                                acpi_table_signatures[temp_id]);
272                         return -ENODEV;
273                 }
274                 break;
275         }
276
277         if (!*header) {
278                 printk(KERN_WARNING PREFIX "%s not present\n",
279                        acpi_table_signatures[id]);
280                 return -ENODEV;
281         }
282
283         /* Map the DSDT header via the pointer in the FADT */
284         if (id == ACPI_DSDT) {
285                 struct fadt_descriptor_rev2 *fadt =
286                     (struct fadt_descriptor_rev2 *)*header;
287
288                 if (fadt->revision == 3 && fadt->Xdsdt) {
289                         *header = (void *)__acpi_map_table(fadt->Xdsdt,
290                                                            sizeof(struct
291                                                                   acpi_table_header));
292                 } else if (fadt->V1_dsdt) {
293                         *header = (void *)__acpi_map_table(fadt->V1_dsdt,
294                                                            sizeof(struct
295                                                                   acpi_table_header));
296                 } else
297                         *header = NULL;
298
299                 if (!*header) {
300                         printk(KERN_WARNING PREFIX "Unable to map DSDT\n");
301                         return -ENODEV;
302                 }
303         }
304
305         return 0;
306 }
307
308 int __init
309 acpi_table_parse_madt_family(enum acpi_table_id id,
310                              unsigned long madt_size,
311                              int entry_id,
312                              acpi_madt_entry_handler handler,
313                              unsigned int max_entries)
314 {
315         void *madt = NULL;
316         acpi_table_entry_header *entry;
317         unsigned int count = 0;
318         unsigned long madt_end;
319         unsigned int i;
320
321         if (!handler)
322                 return -EINVAL;
323
324         /* Locate the MADT (if exists). There should only be one. */
325
326         for (i = 0; i < sdt_count; i++) {
327                 if (sdt_entry[i].id != id)
328                         continue;
329                 madt = (void *)
330                     __acpi_map_table(sdt_entry[i].pa, sdt_entry[i].size);
331                 if (!madt) {
332                         printk(KERN_WARNING PREFIX "Unable to map %s\n",
333                                acpi_table_signatures[id]);
334                         return -ENODEV;
335                 }
336                 break;
337         }
338
339         if (!madt) {
340                 printk(KERN_WARNING PREFIX "%s not present\n",
341                        acpi_table_signatures[id]);
342                 return -ENODEV;
343         }
344
345         madt_end = (unsigned long)madt + sdt_entry[i].size;
346
347         /* Parse all entries looking for a match. */
348
349         entry = (acpi_table_entry_header *)
350             ((unsigned long)madt + madt_size);
351
352         while (((unsigned long)entry) + sizeof(acpi_table_entry_header) <
353                madt_end) {
354                 if (entry->type == entry_id
355                     && (!max_entries || count++ < max_entries))
356                         if (handler(entry, madt_end))
357                                 return -EINVAL;
358
359                 entry = (acpi_table_entry_header *)
360                     ((unsigned long)entry + entry->length);
361         }
362         if (max_entries && count > max_entries) {
363                 printk(KERN_WARNING PREFIX "[%s:0x%02x] ignored %i entries of "
364                        "%i found\n", acpi_table_signatures[id], entry_id,
365                        count - max_entries, count);
366         }
367
368         return count;
369 }
370
371 int __init
372 acpi_table_parse_madt(enum acpi_madt_entry_id id,
373                       acpi_madt_entry_handler handler, unsigned int max_entries)
374 {
375         return acpi_table_parse_madt_family(ACPI_APIC,
376                                             sizeof(struct acpi_table_madt), id,
377                                             handler, max_entries);
378 }
379
380 int __init acpi_table_parse(enum acpi_table_id id, acpi_table_handler handler)
381 {
382         int count = 0;
383         unsigned int i = 0;
384
385         if (!handler)
386                 return -EINVAL;
387
388         for (i = 0; i < sdt_count; i++) {
389                 if (sdt_entry[i].id != id)
390                         continue;
391                 count++;
392                 if (count == 1)
393                         handler(sdt_entry[i].pa, sdt_entry[i].size);
394
395                 else
396                         printk(KERN_WARNING PREFIX
397                                "%d duplicate %s table ignored.\n", count,
398                                acpi_table_signatures[id]);
399         }
400
401         return count;
402 }
403
404 static int __init acpi_table_get_sdt(struct acpi_table_rsdp *rsdp)
405 {
406         struct acpi_table_header *header = NULL;
407         unsigned int i, id = 0;
408
409         if (!rsdp)
410                 return -EINVAL;
411
412         /* First check XSDT (but only on ACPI 2.0-compatible systems) */
413
414         if ((rsdp->revision >= 2) &&
415             (((struct acpi20_table_rsdp *)rsdp)->xsdt_address)) {
416
417                 struct acpi_table_xsdt *mapped_xsdt = NULL;
418
419                 sdt_pa = ((struct acpi20_table_rsdp *)rsdp)->xsdt_address;
420
421                 /* map in just the header */
422                 header = (struct acpi_table_header *)
423                     __acpi_map_table(sdt_pa, sizeof(struct acpi_table_header));
424
425                 if (!header) {
426                         printk(KERN_WARNING PREFIX
427                                "Unable to map XSDT header\n");
428                         return -ENODEV;
429                 }
430
431                 /* remap in the entire table before processing */
432                 mapped_xsdt = (struct acpi_table_xsdt *)
433                     __acpi_map_table(sdt_pa, header->length);
434                 if (!mapped_xsdt) {
435                         printk(KERN_WARNING PREFIX "Unable to map XSDT\n");
436                         return -ENODEV;
437                 }
438                 header = &mapped_xsdt->header;
439
440                 if (strncmp(header->signature, "XSDT", 4)) {
441                         printk(KERN_WARNING PREFIX
442                                "XSDT signature incorrect\n");
443                         return -ENODEV;
444                 }
445
446                 if (acpi_table_compute_checksum(header, header->length)) {
447                         printk(KERN_WARNING PREFIX "Invalid XSDT checksum\n");
448                         return -ENODEV;
449                 }
450
451                 sdt_count =
452                     (header->length - sizeof(struct acpi_table_header)) >> 3;
453                 if (sdt_count > ACPI_MAX_TABLES) {
454                         printk(KERN_WARNING PREFIX
455                                "Truncated %lu XSDT entries\n",
456                                (sdt_count - ACPI_MAX_TABLES));
457                         sdt_count = ACPI_MAX_TABLES;
458                 }
459
460                 for (i = 0; i < sdt_count; i++)
461                         sdt_entry[i].pa = (unsigned long)mapped_xsdt->entry[i];
462         }
463
464         /* Then check RSDT */
465
466         else if (rsdp->rsdt_address) {
467
468                 struct acpi_table_rsdt *mapped_rsdt = NULL;
469
470                 sdt_pa = rsdp->rsdt_address;
471
472                 /* map in just the header */
473                 header = (struct acpi_table_header *)
474                     __acpi_map_table(sdt_pa, sizeof(struct acpi_table_header));
475                 if (!header) {
476                         printk(KERN_WARNING PREFIX
477                                "Unable to map RSDT header\n");
478                         return -ENODEV;
479                 }
480
481                 /* remap in the entire table before processing */
482                 mapped_rsdt = (struct acpi_table_rsdt *)
483                     __acpi_map_table(sdt_pa, header->length);
484                 if (!mapped_rsdt) {
485                         printk(KERN_WARNING PREFIX "Unable to map RSDT\n");
486                         return -ENODEV;
487                 }
488                 header = &mapped_rsdt->header;
489
490                 if (strncmp(header->signature, "RSDT", 4)) {
491                         printk(KERN_WARNING PREFIX
492                                "RSDT signature incorrect\n");
493                         return -ENODEV;
494                 }
495
496                 if (acpi_table_compute_checksum(header, header->length)) {
497                         printk(KERN_WARNING PREFIX "Invalid RSDT checksum\n");
498                         return -ENODEV;
499                 }
500
501                 sdt_count =
502                     (header->length - sizeof(struct acpi_table_header)) >> 2;
503                 if (sdt_count > ACPI_MAX_TABLES) {
504                         printk(KERN_WARNING PREFIX
505                                "Truncated %lu RSDT entries\n",
506                                (sdt_count - ACPI_MAX_TABLES));
507                         sdt_count = ACPI_MAX_TABLES;
508                 }
509
510                 for (i = 0; i < sdt_count; i++)
511                         sdt_entry[i].pa = (unsigned long)mapped_rsdt->entry[i];
512         }
513
514         else {
515                 printk(KERN_WARNING PREFIX
516                        "No System Description Table (RSDT/XSDT) specified in RSDP\n");
517                 return -ENODEV;
518         }
519
520         acpi_table_print(header, sdt_pa);
521
522         for (i = 0; i < sdt_count; i++) {
523
524                 /* map in just the header */
525                 header = (struct acpi_table_header *)
526                     __acpi_map_table(sdt_entry[i].pa,
527                                      sizeof(struct acpi_table_header));
528                 if (!header)
529                         continue;
530
531                 /* remap in the entire table before processing */
532                 header = (struct acpi_table_header *)
533                     __acpi_map_table(sdt_entry[i].pa, header->length);
534                 if (!header)
535                         continue;
536
537                 acpi_table_print(header, sdt_entry[i].pa);
538
539                 if (acpi_table_compute_checksum(header, header->length)) {
540                         printk(KERN_WARNING "  >>> ERROR: Invalid checksum\n");
541                         continue;
542                 }
543
544                 sdt_entry[i].size = header->length;
545
546                 for (id = 0; id < ACPI_TABLE_COUNT; id++) {
547                         if (!strncmp((char *)&header->signature,
548                                      acpi_table_signatures[id],
549                                      sizeof(header->signature))) {
550                                 sdt_entry[i].id = id;
551                         }
552                 }
553         }
554
555         /* 
556          * The DSDT is *not* in the RSDT (why not? no idea.) but we want
557          * to print its info, because this is what people usually blacklist
558          * against. Unfortunately, we don't know the phys_addr, so just
559          * print 0. Maybe no one will notice.
560          */
561         if (!acpi_get_table_header_early(ACPI_DSDT, &header))
562                 acpi_table_print(header, 0);
563
564         return 0;
565 }
566
567 /*
568  * acpi_table_init()
569  *
570  * find RSDP, find and checksum SDT/XSDT.
571  * checksum all tables, print SDT/XSDT
572  * 
573  * result: sdt_entry[] is initialized
574  */
575
576 int __init acpi_table_init(void)
577 {
578         struct acpi_table_rsdp *rsdp = NULL;
579         unsigned long rsdp_phys = 0;
580         int result = 0;
581
582         /* Locate and map the Root System Description Table (RSDP) */
583
584         rsdp_phys = acpi_find_rsdp();
585         if (!rsdp_phys) {
586                 printk(KERN_ERR PREFIX "Unable to locate RSDP\n");
587                 return -ENODEV;
588         }
589
590         rsdp = (struct acpi_table_rsdp *)__acpi_map_table(rsdp_phys,
591                 sizeof(struct acpi_table_rsdp));
592         if (!rsdp) {
593                 printk(KERN_WARNING PREFIX "Unable to map RSDP\n");
594                 return -ENODEV;
595         }
596
597         printk(KERN_DEBUG PREFIX
598                "RSDP (v%3.3d %6.6s                                ) @ 0x%p\n",
599                rsdp->revision, rsdp->oem_id, (void *)rsdp_phys);
600
601         if (rsdp->revision < 2)
602                 result =
603                     acpi_table_compute_checksum(rsdp,
604                                                 sizeof(struct acpi_table_rsdp));
605         else
606                 result =
607                     acpi_table_compute_checksum(rsdp,
608                                                 ((struct acpi20_table_rsdp *)
609                                                  rsdp)->length);
610
611         if (result) {
612                 printk(KERN_WARNING "  >>> ERROR: Invalid checksum\n");
613                 return -ENODEV;
614         }
615
616         /* Locate and map the System Description table (RSDT/XSDT) */
617
618         if (acpi_table_get_sdt(rsdp))
619                 return -ENODEV;
620
621         return 0;
622 }