ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-2.6.6.tar.bz2
[linux-2.6.git] / arch / i386 / kernel / efi.c
1 /*
2  * Extensible Firmware Interface
3  *
4  * Based on Extensible Firmware Interface Specification version 1.0
5  *
6  * Copyright (C) 1999 VA Linux Systems
7  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
8  * Copyright (C) 1999-2002 Hewlett-Packard Co.
9  *      David Mosberger-Tang <davidm@hpl.hp.com>
10  *      Stephane Eranian <eranian@hpl.hp.com>
11  *
12  * All EFI Runtime Services are not implemented yet as EFI only
13  * supports physical mode addressing on SoftSDV. This is to be fixed
14  * in a future version.  --drummond 1999-07-20
15  *
16  * Implemented EFI runtime services and virtual mode calls.  --davidm
17  *
18  * Goutham Rao: <goutham.rao@intel.com>
19  *      Skip non-WB memory and ignore empty memory ranges.
20  */
21
22 #include <linux/config.h>
23 #include <linux/kernel.h>
24 #include <linux/init.h>
25 #include <linux/mm.h>
26 #include <linux/types.h>
27 #include <linux/time.h>
28 #include <linux/spinlock.h>
29 #include <linux/bootmem.h>
30 #include <linux/ioport.h>
31 #include <linux/module.h>
32 #include <linux/efi.h>
33
34 #include <asm/setup.h>
35 #include <asm/io.h>
36 #include <asm/page.h>
37 #include <asm/pgtable.h>
38 #include <asm/processor.h>
39 #include <asm/desc.h>
40 #include <asm/pgalloc.h>
41 #include <asm/tlbflush.h>
42
43 #define EFI_DEBUG       0
44 #define PFX             "EFI: "
45
46 extern efi_status_t asmlinkage efi_call_phys(void *, ...);
47
48 struct efi efi;
49 EXPORT_SYMBOL(efi);
50 struct efi efi_phys __initdata;
51 struct efi_memory_map memmap __initdata;
52
53 /*
54  * We require an early boot_ioremap mapping mechanism initially
55  */
56 extern void * boot_ioremap(unsigned long, unsigned long);
57
58 /*
59  * To make EFI call EFI runtime service in physical addressing mode we need
60  * prelog/epilog before/after the invocation to disable interrupt, to
61  * claim EFI runtime service handler exclusively and to duplicate a memory in
62  * low memory space say 0 - 3G.
63  */
64
65 static unsigned long efi_rt_eflags;
66 static spinlock_t efi_rt_lock = SPIN_LOCK_UNLOCKED;
67 static pgd_t efi_bak_pg_dir_pointer[2];
68
69 static void efi_call_phys_prelog(void)
70 {
71         unsigned long cr4;
72         unsigned long temp;
73
74         spin_lock(&efi_rt_lock);
75         local_irq_save(efi_rt_eflags);
76
77         /*
78          * If I don't have PSE, I should just duplicate two entries in page
79          * directory. If I have PSE, I just need to duplicate one entry in
80          * page directory.
81          */
82         __asm__ __volatile__("movl %%cr4, %0":"=r"(cr4));
83
84         if (cr4 & X86_CR4_PSE) {
85                 efi_bak_pg_dir_pointer[0].pgd =
86                     swapper_pg_dir[pgd_index(0)].pgd;
87                 swapper_pg_dir[0].pgd =
88                     swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
89         } else {
90                 efi_bak_pg_dir_pointer[0].pgd =
91                     swapper_pg_dir[pgd_index(0)].pgd;
92                 efi_bak_pg_dir_pointer[1].pgd =
93                     swapper_pg_dir[pgd_index(0x400000)].pgd;
94                 swapper_pg_dir[pgd_index(0)].pgd =
95                     swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
96                 temp = PAGE_OFFSET + 0x400000;
97                 swapper_pg_dir[pgd_index(0x400000)].pgd =
98                     swapper_pg_dir[pgd_index(temp)].pgd;
99         }
100
101         /*
102          * After the lock is released, the original page table is restored.
103          */
104         local_flush_tlb();
105
106         cpu_gdt_descr[0].address = __pa(cpu_gdt_descr[0].address);
107         __asm__ __volatile__("lgdt %0":"=m"
108                             (*(struct Xgt_desc_struct *) __pa(&cpu_gdt_descr[0])));
109 }
110
111 static void efi_call_phys_epilog(void)
112 {
113         unsigned long cr4;
114
115         cpu_gdt_descr[0].address =
116                 (unsigned long) __va(cpu_gdt_descr[0].address);
117         __asm__ __volatile__("lgdt %0":"=m"(cpu_gdt_descr));
118         __asm__ __volatile__("movl %%cr4, %0":"=r"(cr4));
119
120         if (cr4 & X86_CR4_PSE) {
121                 swapper_pg_dir[pgd_index(0)].pgd =
122                     efi_bak_pg_dir_pointer[0].pgd;
123         } else {
124                 swapper_pg_dir[pgd_index(0)].pgd =
125                     efi_bak_pg_dir_pointer[0].pgd;
126                 swapper_pg_dir[pgd_index(0x400000)].pgd =
127                     efi_bak_pg_dir_pointer[1].pgd;
128         }
129
130         /*
131          * After the lock is released, the original page table is restored.
132          */
133         local_flush_tlb();
134
135         local_irq_restore(efi_rt_eflags);
136         spin_unlock(&efi_rt_lock);
137 }
138
139 static efi_status_t
140 phys_efi_set_virtual_address_map(unsigned long memory_map_size,
141                                  unsigned long descriptor_size,
142                                  u32 descriptor_version,
143                                  efi_memory_desc_t *virtual_map)
144 {
145         efi_status_t status;
146
147         efi_call_phys_prelog();
148         status = efi_call_phys(efi_phys.set_virtual_address_map,
149                                      memory_map_size, descriptor_size,
150                                      descriptor_version, virtual_map);
151         efi_call_phys_epilog();
152         return status;
153 }
154
155 efi_status_t
156 phys_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
157 {
158         efi_status_t status;
159
160         efi_call_phys_prelog();
161         status = efi_call_phys(efi_phys.get_time, tm, tc);
162         efi_call_phys_epilog();
163         return status;
164 }
165
166 inline int efi_set_rtc_mmss(unsigned long nowtime)
167 {
168         int real_seconds, real_minutes;
169         efi_status_t    status;
170         efi_time_t      eft;
171         efi_time_cap_t  cap;
172
173         spin_lock(&efi_rt_lock);
174         status = efi.get_time(&eft, &cap);
175         spin_unlock(&efi_rt_lock);
176         if (status != EFI_SUCCESS)
177                 panic("Ooops, efitime: can't read time!\n");
178         real_seconds = nowtime % 60;
179         real_minutes = nowtime / 60;
180
181         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
182                 real_minutes += 30;
183         real_minutes %= 60;
184
185         eft.minute = real_minutes;
186         eft.second = real_seconds;
187
188         if (status != EFI_SUCCESS) {
189                 printk("Ooops: efitime: can't read time!\n");
190                 return -1;
191         }
192         return 0;
193 }
194 /*
195  * This should only be used during kernel init and before runtime
196  * services have been remapped, therefore, we'll need to call in physical
197  * mode.  Note, this call isn't used later, so mark it __init.
198  */
199 inline unsigned long __init efi_get_time(void)
200 {
201         efi_status_t status;
202         efi_time_t eft;
203         efi_time_cap_t cap;
204
205         status = phys_efi_get_time(&eft, &cap);
206         if (status != EFI_SUCCESS)
207                 printk("Oops: efitime: can't read time status: 0x%lx\n",status);
208
209         return mktime(eft.year, eft.month, eft.day, eft.hour,
210                         eft.minute, eft.second);
211 }
212
213 int is_available_memory(efi_memory_desc_t * md)
214 {
215         if (!(md->attribute & EFI_MEMORY_WB))
216                 return 0;
217
218         switch (md->type) {
219                 case EFI_LOADER_CODE:
220                 case EFI_LOADER_DATA:
221                 case EFI_BOOT_SERVICES_CODE:
222                 case EFI_BOOT_SERVICES_DATA:
223                 case EFI_CONVENTIONAL_MEMORY:
224                         return 1;
225         }
226         return 0;
227 }
228
229 /*
230  * We need to map the EFI memory map again after paging_init().
231  */
232 void __init efi_map_memmap(void)
233 {
234         memmap.map = NULL;
235
236         memmap.map = (efi_memory_desc_t *)
237                 bt_ioremap((unsigned long) memmap.phys_map,
238                         (memmap.nr_map * sizeof(efi_memory_desc_t)));
239
240         if (memmap.map == NULL)
241                 printk(KERN_ERR PFX "Could not remap the EFI memmap!\n");
242 }
243
244 void __init print_efi_memmap(void)
245 {
246         efi_memory_desc_t *md;
247         int i;
248
249         for (i = 0; i < memmap.nr_map; i++) {
250                 md = &memmap.map[i];
251                 printk(KERN_INFO "mem%02u: type=%u, attr=0x%llx, "
252                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
253                         i, md->type, md->attribute, md->phys_addr,
254                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
255                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
256         }
257 }
258
259 /*
260  * Walks the EFI memory map and calls CALLBACK once for each EFI
261  * memory descriptor that has memory that is available for kernel use.
262  */
263 void efi_memmap_walk(efi_freemem_callback_t callback, void *arg)
264 {
265         int prev_valid = 0;
266         struct range {
267                 unsigned long start;
268                 unsigned long end;
269         } prev, curr;
270         efi_memory_desc_t *md;
271         unsigned long start, end;
272         int i;
273
274         for (i = 0; i < memmap.nr_map; i++) {
275                 md = &memmap.map[i];
276
277                 if ((md->num_pages == 0) || (!is_available_memory(md)))
278                         continue;
279
280                 curr.start = md->phys_addr;
281                 curr.end = curr.start + (md->num_pages << EFI_PAGE_SHIFT);
282
283                 if (!prev_valid) {
284                         prev = curr;
285                         prev_valid = 1;
286                 } else {
287                         if (curr.start < prev.start)
288                                 printk(KERN_INFO PFX "Unordered memory map\n");
289                         if (prev.end == curr.start)
290                                 prev.end = curr.end;
291                         else {
292                                 start =
293                                     (unsigned long) (PAGE_ALIGN(prev.start));
294                                 end = (unsigned long) (prev.end & PAGE_MASK);
295                                 if ((end > start)
296                                     && (*callback) (start, end, arg) < 0)
297                                         return;
298                                 prev = curr;
299                         }
300                 }
301         }
302         if (prev_valid) {
303                 start = (unsigned long) PAGE_ALIGN(prev.start);
304                 end = (unsigned long) (prev.end & PAGE_MASK);
305                 if (end > start)
306                         (*callback) (start, end, arg);
307         }
308 }
309
310 void __init efi_init(void)
311 {
312         efi_config_table_t *config_tables;
313         efi_runtime_services_t *runtime;
314         efi_char16_t *c16;
315         char vendor[100] = "unknown";
316         unsigned long num_config_tables;
317         int i = 0;
318
319         memset(&efi, 0, sizeof(efi) );
320         memset(&efi_phys, 0, sizeof(efi_phys));
321
322         efi_phys.systab = EFI_SYSTAB;
323         memmap.phys_map = EFI_MEMMAP;
324         memmap.nr_map = EFI_MEMMAP_SIZE/EFI_MEMDESC_SIZE;
325         memmap.desc_version = EFI_MEMDESC_VERSION;
326
327         efi.systab = (efi_system_table_t *)
328                 boot_ioremap((unsigned long) efi_phys.systab,
329                         sizeof(efi_system_table_t));
330         /*
331          * Verify the EFI Table
332          */
333         if (efi.systab == NULL)
334                 printk(KERN_ERR PFX "Woah! Couldn't map the EFI system table.\n");
335         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
336                 printk(KERN_ERR PFX "Woah! EFI system table signature incorrect\n");
337         if ((efi.systab->hdr.revision ^ EFI_SYSTEM_TABLE_REVISION) >> 16 != 0)
338                 printk(KERN_ERR PFX
339                        "Warning: EFI system table major version mismatch: "
340                        "got %d.%02d, expected %d.%02d\n",
341                        efi.systab->hdr.revision >> 16,
342                        efi.systab->hdr.revision & 0xffff,
343                        EFI_SYSTEM_TABLE_REVISION >> 16,
344                        EFI_SYSTEM_TABLE_REVISION & 0xffff);
345         /*
346          * Grab some details from the system table
347          */
348         num_config_tables = efi.systab->nr_tables;
349         config_tables = (efi_config_table_t *)efi.systab->tables;
350         runtime = efi.systab->runtime;
351
352         /*
353          * Show what we know for posterity
354          */
355         c16 = (efi_char16_t *) boot_ioremap(efi.systab->fw_vendor, 2);
356         if (c16) {
357                 for (i = 0; i < sizeof(vendor) && *c16; ++i)
358                         vendor[i] = *c16++;
359                 vendor[i] = '\0';
360         } else
361                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
362
363         printk(KERN_INFO PFX "EFI v%u.%.02u by %s \n",
364                efi.systab->hdr.revision >> 16,
365                efi.systab->hdr.revision & 0xffff, vendor);
366
367         /*
368          * Let's see what config tables the firmware passed to us.
369          */
370         config_tables = (efi_config_table_t *)
371                                 boot_ioremap((unsigned long) config_tables,
372                                 num_config_tables * sizeof(efi_config_table_t));
373
374         if (config_tables == NULL)
375                 printk(KERN_ERR PFX "Could not map EFI Configuration Table!\n");
376
377         for (i = 0; i < num_config_tables; i++) {
378                 if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
379                         efi.mps = (void *)config_tables[i].table;
380                         printk(KERN_INFO " MPS=0x%lx ", config_tables[i].table);
381                 } else
382                     if (efi_guidcmp(config_tables[i].guid, ACPI_20_TABLE_GUID) == 0) {
383                         efi.acpi20 = __va(config_tables[i].table);
384                         printk(KERN_INFO " ACPI 2.0=0x%lx ", config_tables[i].table);
385                 } else
386                     if (efi_guidcmp(config_tables[i].guid, ACPI_TABLE_GUID) == 0) {
387                         efi.acpi = __va(config_tables[i].table);
388                         printk(KERN_INFO " ACPI=0x%lx ", config_tables[i].table);
389                 } else
390                     if (efi_guidcmp(config_tables[i].guid, SMBIOS_TABLE_GUID) == 0) {
391                         efi.smbios = (void *) config_tables[i].table;
392                         printk(KERN_INFO " SMBIOS=0x%lx ", config_tables[i].table);
393                 } else
394                     if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
395                         efi.hcdp = (void *)config_tables[i].table;
396                         printk(KERN_INFO " HCDP=0x%lx ", config_tables[i].table);
397                 } else
398                     if (efi_guidcmp(config_tables[i].guid, UGA_IO_PROTOCOL_GUID) == 0) {
399                         efi.uga = (void *)config_tables[i].table;
400                         printk(KERN_INFO " UGA=0x%lx ", config_tables[i].table);
401                 }
402         }
403         printk("\n");
404
405         /*
406          * Check out the runtime services table. We need to map
407          * the runtime services table so that we can grab the physical
408          * address of several of the EFI runtime functions, needed to
409          * set the firmware into virtual mode.
410          */
411
412         runtime = (efi_runtime_services_t *) boot_ioremap((unsigned long)
413                                                 runtime,
414                                                 sizeof(efi_runtime_services_t));
415         if (runtime != NULL) {
416                 /*
417                  * We will only need *early* access to the following
418                  * two EFI runtime services before set_virtual_address_map
419                  * is invoked.
420                  */
421                 efi_phys.get_time = (efi_get_time_t *) runtime->get_time;
422                 efi_phys.set_virtual_address_map =
423                         (efi_set_virtual_address_map_t *)
424                                 runtime->set_virtual_address_map;
425         } else
426                 printk(KERN_ERR PFX "Could not map the runtime service table!\n");
427
428         /* Map the EFI memory map for use until paging_init() */
429
430         memmap.map = (efi_memory_desc_t *)
431                 boot_ioremap((unsigned long) EFI_MEMMAP, EFI_MEMMAP_SIZE);
432
433         if (memmap.map == NULL)
434                 printk(KERN_ERR PFX "Could not map the EFI memory map!\n");
435
436         if (EFI_MEMDESC_SIZE != sizeof(efi_memory_desc_t)) {
437                 printk(KERN_WARNING PFX "Warning! Kernel-defined memdesc doesn't "
438                            "match the one from EFI!\n");
439         }
440 #if EFI_DEBUG
441         print_efi_memmap();
442 #endif
443 }
444
445 /*
446  * This function will switch the EFI runtime services to virtual mode.
447  * Essentially, look through the EFI memmap and map every region that
448  * has the runtime attribute bit set in its memory descriptor and update
449  * that memory descriptor with the virtual address obtained from ioremap().
450  * This enables the runtime services to be called without having to
451  * thunk back into physical mode for every invocation.
452  */
453
454 void __init efi_enter_virtual_mode(void)
455 {
456         efi_memory_desc_t *md;
457         efi_status_t status;
458         int i;
459
460         efi.systab = NULL;
461
462         for (i = 0; i < memmap.nr_map; i++) {
463                 md = &memmap.map[i];
464
465                 if (md->attribute & EFI_MEMORY_RUNTIME) {
466                         md->virt_addr =
467                                 (unsigned long)ioremap(md->phys_addr,
468                                         md->num_pages << EFI_PAGE_SHIFT);
469                         if (!(unsigned long)md->virt_addr) {
470                                 printk(KERN_ERR PFX "ioremap of 0x%lX failed\n",
471                                         (unsigned long)md->phys_addr);
472                         }
473
474                         if (((unsigned long)md->phys_addr <=
475                                         (unsigned long)efi_phys.systab) &&
476                                 ((unsigned long)efi_phys.systab <
477                                         md->phys_addr +
478                                         ((unsigned long)md->num_pages <<
479                                                 EFI_PAGE_SHIFT))) {
480                                 unsigned long addr;
481
482                                 addr = md->virt_addr - md->phys_addr +
483                                                 (unsigned long)efi_phys.systab;
484                                 efi.systab = (efi_system_table_t *)addr;
485                         }
486                 }
487         }
488
489         if (!efi.systab)
490                 BUG();
491
492         status = phys_efi_set_virtual_address_map(
493                         sizeof(efi_memory_desc_t) * memmap.nr_map,
494                         sizeof(efi_memory_desc_t),
495                         memmap.desc_version,
496                         memmap.phys_map);
497
498         if (status != EFI_SUCCESS) {
499                 printk (KERN_ALERT "You are screwed! "
500                         "Unable to switch EFI into virtual mode "
501                         "(status=%lx)\n", status);
502                 panic("EFI call to SetVirtualAddressMap() failed!");
503         }
504
505         /*
506          * Now that EFI is in virtual mode, update the function
507          * pointers in the runtime service table to the new virtual addresses.
508          */
509
510         efi.get_time = (efi_get_time_t *) efi.systab->runtime->get_time;
511         efi.set_time = (efi_set_time_t *) efi.systab->runtime->set_time;
512         efi.get_wakeup_time = (efi_get_wakeup_time_t *)
513                                         efi.systab->runtime->get_wakeup_time;
514         efi.set_wakeup_time = (efi_set_wakeup_time_t *)
515                                         efi.systab->runtime->set_wakeup_time;
516         efi.get_variable = (efi_get_variable_t *)
517                                         efi.systab->runtime->get_variable;
518         efi.get_next_variable = (efi_get_next_variable_t *)
519                                         efi.systab->runtime->get_next_variable;
520         efi.set_variable = (efi_set_variable_t *)
521                                         efi.systab->runtime->set_variable;
522         efi.get_next_high_mono_count = (efi_get_next_high_mono_count_t *)
523                                         efi.systab->runtime->get_next_high_mono_count;
524         efi.reset_system = (efi_reset_system_t *)
525                                         efi.systab->runtime->reset_system;
526 }
527
528 void __init
529 efi_initialize_iomem_resources(struct resource *code_resource,
530                                struct resource *data_resource)
531 {
532         struct resource *res;
533         efi_memory_desc_t *md;
534         int i;
535
536         for (i = 0; i < memmap.nr_map; i++) {
537                 md = &memmap.map[i];
538
539                 if ((md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)) >
540                     0x100000000ULL)
541                         continue;
542                 res = alloc_bootmem_low(sizeof(struct resource));
543                 switch (md->type) {
544                 case EFI_RESERVED_TYPE:
545                         res->name = "Reserved Memory";
546                         break;
547                 case EFI_LOADER_CODE:
548                         res->name = "Loader Code";
549                         break;
550                 case EFI_LOADER_DATA:
551                         res->name = "Loader Data";
552                         break;
553                 case EFI_BOOT_SERVICES_DATA:
554                         res->name = "BootServices Data";
555                         break;
556                 case EFI_BOOT_SERVICES_CODE:
557                         res->name = "BootServices Code";
558                         break;
559                 case EFI_RUNTIME_SERVICES_CODE:
560                         res->name = "Runtime Service Code";
561                         break;
562                 case EFI_RUNTIME_SERVICES_DATA:
563                         res->name = "Runtime Service Data";
564                         break;
565                 case EFI_CONVENTIONAL_MEMORY:
566                         res->name = "Conventional Memory";
567                         break;
568                 case EFI_UNUSABLE_MEMORY:
569                         res->name = "Unusable Memory";
570                         break;
571                 case EFI_ACPI_RECLAIM_MEMORY:
572                         res->name = "ACPI Reclaim";
573                         break;
574                 case EFI_ACPI_MEMORY_NVS:
575                         res->name = "ACPI NVS";
576                         break;
577                 case EFI_MEMORY_MAPPED_IO:
578                         res->name = "Memory Mapped IO";
579                         break;
580                 case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
581                         res->name = "Memory Mapped IO Port Space";
582                         break;
583                 default:
584                         res->name = "Reserved";
585                         break;
586                 }
587                 res->start = md->phys_addr;
588                 res->end = res->start + ((md->num_pages << EFI_PAGE_SHIFT) - 1);
589                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
590                 if (request_resource(&iomem_resource, res) < 0)
591                         printk(KERN_ERR PFX "Failed to allocate res %s : 0x%lx-0x%lx\n",
592                                 res->name, res->start, res->end);
593                 /*
594                  * We don't know which region contains kernel data so we try
595                  * it repeatedly and let the resource manager test it.
596                  */
597                 if (md->type == EFI_CONVENTIONAL_MEMORY) {
598                         request_resource(res, code_resource);
599                         request_resource(res, data_resource);
600                 }
601         }
602 }
603
604 /*
605  * Convenience functions to obtain memory types and attributes
606  */
607
608 u32 efi_mem_type(unsigned long phys_addr)
609 {
610         efi_memory_desc_t *md;
611         int i;
612
613         for (i = 0; i < memmap.nr_map; i++) {
614                 md = &memmap.map[i];
615                 if ((md->phys_addr <= phys_addr) && (phys_addr <
616                         (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
617                         return md->type;
618         }
619         return 0;
620 }
621
622 u64 efi_mem_attributes(unsigned long phys_addr)
623 {
624         efi_memory_desc_t *md;
625         int i;
626
627         for (i = 0; i < memmap.nr_map; i++) {
628                 md = &memmap.map[i];
629                 if ((md->phys_addr <= phys_addr) && (phys_addr <
630                         (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
631                         return md->attribute;
632         }
633         return 0;
634 }