Linux-2.6.12-rc2
[linux-3.10.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/tlbflush.h>
41
42 #define EFI_DEBUG       0
43 #define PFX             "EFI: "
44
45 extern efi_status_t asmlinkage efi_call_phys(void *, ...);
46
47 struct efi efi;
48 EXPORT_SYMBOL(efi);
49 static struct efi efi_phys __initdata;
50 struct efi_memory_map memmap __initdata;
51
52 /*
53  * We require an early boot_ioremap mapping mechanism initially
54  */
55 extern void * boot_ioremap(unsigned long, unsigned long);
56
57 /*
58  * To make EFI call EFI runtime service in physical addressing mode we need
59  * prelog/epilog before/after the invocation to disable interrupt, to
60  * claim EFI runtime service handler exclusively and to duplicate a memory in
61  * low memory space say 0 - 3G.
62  */
63
64 static unsigned long efi_rt_eflags;
65 static DEFINE_SPINLOCK(efi_rt_lock);
66 static pgd_t efi_bak_pg_dir_pointer[2];
67
68 static void efi_call_phys_prelog(void)
69 {
70         unsigned long cr4;
71         unsigned long temp;
72
73         spin_lock(&efi_rt_lock);
74         local_irq_save(efi_rt_eflags);
75
76         /*
77          * If I don't have PSE, I should just duplicate two entries in page
78          * directory. If I have PSE, I just need to duplicate one entry in
79          * page directory.
80          */
81         __asm__ __volatile__("movl %%cr4, %0":"=r"(cr4));
82
83         if (cr4 & X86_CR4_PSE) {
84                 efi_bak_pg_dir_pointer[0].pgd =
85                     swapper_pg_dir[pgd_index(0)].pgd;
86                 swapper_pg_dir[0].pgd =
87                     swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
88         } else {
89                 efi_bak_pg_dir_pointer[0].pgd =
90                     swapper_pg_dir[pgd_index(0)].pgd;
91                 efi_bak_pg_dir_pointer[1].pgd =
92                     swapper_pg_dir[pgd_index(0x400000)].pgd;
93                 swapper_pg_dir[pgd_index(0)].pgd =
94                     swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
95                 temp = PAGE_OFFSET + 0x400000;
96                 swapper_pg_dir[pgd_index(0x400000)].pgd =
97                     swapper_pg_dir[pgd_index(temp)].pgd;
98         }
99
100         /*
101          * After the lock is released, the original page table is restored.
102          */
103         local_flush_tlb();
104
105         cpu_gdt_descr[0].address = __pa(cpu_gdt_descr[0].address);
106         __asm__ __volatile__("lgdt %0":"=m"
107                             (*(struct Xgt_desc_struct *) __pa(&cpu_gdt_descr[0])));
108 }
109
110 static void efi_call_phys_epilog(void)
111 {
112         unsigned long cr4;
113
114         cpu_gdt_descr[0].address =
115                 (unsigned long) __va(cpu_gdt_descr[0].address);
116         __asm__ __volatile__("lgdt %0":"=m"(cpu_gdt_descr));
117         __asm__ __volatile__("movl %%cr4, %0":"=r"(cr4));
118
119         if (cr4 & X86_CR4_PSE) {
120                 swapper_pg_dir[pgd_index(0)].pgd =
121                     efi_bak_pg_dir_pointer[0].pgd;
122         } else {
123                 swapper_pg_dir[pgd_index(0)].pgd =
124                     efi_bak_pg_dir_pointer[0].pgd;
125                 swapper_pg_dir[pgd_index(0x400000)].pgd =
126                     efi_bak_pg_dir_pointer[1].pgd;
127         }
128
129         /*
130          * After the lock is released, the original page table is restored.
131          */
132         local_flush_tlb();
133
134         local_irq_restore(efi_rt_eflags);
135         spin_unlock(&efi_rt_lock);
136 }
137
138 static efi_status_t
139 phys_efi_set_virtual_address_map(unsigned long memory_map_size,
140                                  unsigned long descriptor_size,
141                                  u32 descriptor_version,
142                                  efi_memory_desc_t *virtual_map)
143 {
144         efi_status_t status;
145
146         efi_call_phys_prelog();
147         status = efi_call_phys(efi_phys.set_virtual_address_map,
148                                      memory_map_size, descriptor_size,
149                                      descriptor_version, virtual_map);
150         efi_call_phys_epilog();
151         return status;
152 }
153
154 static efi_status_t
155 phys_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
156 {
157         efi_status_t status;
158
159         efi_call_phys_prelog();
160         status = efi_call_phys(efi_phys.get_time, tm, tc);
161         efi_call_phys_epilog();
162         return status;
163 }
164
165 inline int efi_set_rtc_mmss(unsigned long nowtime)
166 {
167         int real_seconds, real_minutes;
168         efi_status_t    status;
169         efi_time_t      eft;
170         efi_time_cap_t  cap;
171
172         spin_lock(&efi_rt_lock);
173         status = efi.get_time(&eft, &cap);
174         spin_unlock(&efi_rt_lock);
175         if (status != EFI_SUCCESS)
176                 panic("Ooops, efitime: can't read time!\n");
177         real_seconds = nowtime % 60;
178         real_minutes = nowtime / 60;
179
180         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
181                 real_minutes += 30;
182         real_minutes %= 60;
183
184         eft.minute = real_minutes;
185         eft.second = real_seconds;
186
187         if (status != EFI_SUCCESS) {
188                 printk("Ooops: efitime: can't read time!\n");
189                 return -1;
190         }
191         return 0;
192 }
193 /*
194  * This should only be used during kernel init and before runtime
195  * services have been remapped, therefore, we'll need to call in physical
196  * mode.  Note, this call isn't used later, so mark it __init.
197  */
198 inline unsigned long __init efi_get_time(void)
199 {
200         efi_status_t status;
201         efi_time_t eft;
202         efi_time_cap_t cap;
203
204         status = phys_efi_get_time(&eft, &cap);
205         if (status != EFI_SUCCESS)
206                 printk("Oops: efitime: can't read time status: 0x%lx\n",status);
207
208         return mktime(eft.year, eft.month, eft.day, eft.hour,
209                         eft.minute, eft.second);
210 }
211
212 int is_available_memory(efi_memory_desc_t * md)
213 {
214         if (!(md->attribute & EFI_MEMORY_WB))
215                 return 0;
216
217         switch (md->type) {
218                 case EFI_LOADER_CODE:
219                 case EFI_LOADER_DATA:
220                 case EFI_BOOT_SERVICES_CODE:
221                 case EFI_BOOT_SERVICES_DATA:
222                 case EFI_CONVENTIONAL_MEMORY:
223                         return 1;
224         }
225         return 0;
226 }
227
228 /*
229  * We need to map the EFI memory map again after paging_init().
230  */
231 void __init efi_map_memmap(void)
232 {
233         memmap.map = NULL;
234
235         memmap.map = (efi_memory_desc_t *)
236                 bt_ioremap((unsigned long) memmap.phys_map,
237                         (memmap.nr_map * sizeof(efi_memory_desc_t)));
238
239         if (memmap.map == NULL)
240                 printk(KERN_ERR PFX "Could not remap the EFI memmap!\n");
241 }
242
243 #if EFI_DEBUG
244 static 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 #endif  /*  EFI_DEBUG  */
259
260 /*
261  * Walks the EFI memory map and calls CALLBACK once for each EFI
262  * memory descriptor that has memory that is available for kernel use.
263  */
264 void efi_memmap_walk(efi_freemem_callback_t callback, void *arg)
265 {
266         int prev_valid = 0;
267         struct range {
268                 unsigned long start;
269                 unsigned long end;
270         } prev, curr;
271         efi_memory_desc_t *md;
272         unsigned long start, end;
273         int i;
274
275         for (i = 0; i < memmap.nr_map; i++) {
276                 md = &memmap.map[i];
277
278                 if ((md->num_pages == 0) || (!is_available_memory(md)))
279                         continue;
280
281                 curr.start = md->phys_addr;
282                 curr.end = curr.start + (md->num_pages << EFI_PAGE_SHIFT);
283
284                 if (!prev_valid) {
285                         prev = curr;
286                         prev_valid = 1;
287                 } else {
288                         if (curr.start < prev.start)
289                                 printk(KERN_INFO PFX "Unordered memory map\n");
290                         if (prev.end == curr.start)
291                                 prev.end = curr.end;
292                         else {
293                                 start =
294                                     (unsigned long) (PAGE_ALIGN(prev.start));
295                                 end = (unsigned long) (prev.end & PAGE_MASK);
296                                 if ((end > start)
297                                     && (*callback) (start, end, arg) < 0)
298                                         return;
299                                 prev = curr;
300                         }
301                 }
302         }
303         if (prev_valid) {
304                 start = (unsigned long) PAGE_ALIGN(prev.start);
305                 end = (unsigned long) (prev.end & PAGE_MASK);
306                 if (end > start)
307                         (*callback) (start, end, arg);
308         }
309 }
310
311 void __init efi_init(void)
312 {
313         efi_config_table_t *config_tables;
314         efi_runtime_services_t *runtime;
315         efi_char16_t *c16;
316         char vendor[100] = "unknown";
317         unsigned long num_config_tables;
318         int i = 0;
319
320         memset(&efi, 0, sizeof(efi) );
321         memset(&efi_phys, 0, sizeof(efi_phys));
322
323         efi_phys.systab = EFI_SYSTAB;
324         memmap.phys_map = EFI_MEMMAP;
325         memmap.nr_map = EFI_MEMMAP_SIZE/EFI_MEMDESC_SIZE;
326         memmap.desc_version = EFI_MEMDESC_VERSION;
327
328         efi.systab = (efi_system_table_t *)
329                 boot_ioremap((unsigned long) efi_phys.systab,
330                         sizeof(efi_system_table_t));
331         /*
332          * Verify the EFI Table
333          */
334         if (efi.systab == NULL)
335                 printk(KERN_ERR PFX "Woah! Couldn't map the EFI system table.\n");
336         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
337                 printk(KERN_ERR PFX "Woah! EFI system table signature incorrect\n");
338         if ((efi.systab->hdr.revision ^ EFI_SYSTEM_TABLE_REVISION) >> 16 != 0)
339                 printk(KERN_ERR PFX
340                        "Warning: EFI system table major version mismatch: "
341                        "got %d.%02d, expected %d.%02d\n",
342                        efi.systab->hdr.revision >> 16,
343                        efi.systab->hdr.revision & 0xffff,
344                        EFI_SYSTEM_TABLE_REVISION >> 16,
345                        EFI_SYSTEM_TABLE_REVISION & 0xffff);
346         /*
347          * Grab some details from the system table
348          */
349         num_config_tables = efi.systab->nr_tables;
350         config_tables = (efi_config_table_t *)efi.systab->tables;
351         runtime = efi.systab->runtime;
352
353         /*
354          * Show what we know for posterity
355          */
356         c16 = (efi_char16_t *) boot_ioremap(efi.systab->fw_vendor, 2);
357         if (c16) {
358                 for (i = 0; i < sizeof(vendor) && *c16; ++i)
359                         vendor[i] = *c16++;
360                 vendor[i] = '\0';
361         } else
362                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
363
364         printk(KERN_INFO PFX "EFI v%u.%.02u by %s \n",
365                efi.systab->hdr.revision >> 16,
366                efi.systab->hdr.revision & 0xffff, vendor);
367
368         /*
369          * Let's see what config tables the firmware passed to us.
370          */
371         config_tables = (efi_config_table_t *)
372                                 boot_ioremap((unsigned long) config_tables,
373                                 num_config_tables * sizeof(efi_config_table_t));
374
375         if (config_tables == NULL)
376                 printk(KERN_ERR PFX "Could not map EFI Configuration Table!\n");
377
378         for (i = 0; i < num_config_tables; i++) {
379                 if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
380                         efi.mps = (void *)config_tables[i].table;
381                         printk(KERN_INFO " MPS=0x%lx ", config_tables[i].table);
382                 } else
383                     if (efi_guidcmp(config_tables[i].guid, ACPI_20_TABLE_GUID) == 0) {
384                         efi.acpi20 = __va(config_tables[i].table);
385                         printk(KERN_INFO " ACPI 2.0=0x%lx ", config_tables[i].table);
386                 } else
387                     if (efi_guidcmp(config_tables[i].guid, ACPI_TABLE_GUID) == 0) {
388                         efi.acpi = __va(config_tables[i].table);
389                         printk(KERN_INFO " ACPI=0x%lx ", config_tables[i].table);
390                 } else
391                     if (efi_guidcmp(config_tables[i].guid, SMBIOS_TABLE_GUID) == 0) {
392                         efi.smbios = (void *) config_tables[i].table;
393                         printk(KERN_INFO " SMBIOS=0x%lx ", config_tables[i].table);
394                 } else
395                     if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
396                         efi.hcdp = (void *)config_tables[i].table;
397                         printk(KERN_INFO " HCDP=0x%lx ", config_tables[i].table);
398                 } else
399                     if (efi_guidcmp(config_tables[i].guid, UGA_IO_PROTOCOL_GUID) == 0) {
400                         efi.uga = (void *)config_tables[i].table;
401                         printk(KERN_INFO " UGA=0x%lx ", config_tables[i].table);
402                 }
403         }
404         printk("\n");
405
406         /*
407          * Check out the runtime services table. We need to map
408          * the runtime services table so that we can grab the physical
409          * address of several of the EFI runtime functions, needed to
410          * set the firmware into virtual mode.
411          */
412
413         runtime = (efi_runtime_services_t *) boot_ioremap((unsigned long)
414                                                 runtime,
415                                                 sizeof(efi_runtime_services_t));
416         if (runtime != NULL) {
417                 /*
418                  * We will only need *early* access to the following
419                  * two EFI runtime services before set_virtual_address_map
420                  * is invoked.
421                  */
422                 efi_phys.get_time = (efi_get_time_t *) runtime->get_time;
423                 efi_phys.set_virtual_address_map =
424                         (efi_set_virtual_address_map_t *)
425                                 runtime->set_virtual_address_map;
426         } else
427                 printk(KERN_ERR PFX "Could not map the runtime service table!\n");
428
429         /* Map the EFI memory map for use until paging_init() */
430
431         memmap.map = (efi_memory_desc_t *)
432                 boot_ioremap((unsigned long) EFI_MEMMAP, EFI_MEMMAP_SIZE);
433
434         if (memmap.map == NULL)
435                 printk(KERN_ERR PFX "Could not map the EFI memory map!\n");
436
437         if (EFI_MEMDESC_SIZE != sizeof(efi_memory_desc_t)) {
438                 printk(KERN_WARNING PFX "Warning! Kernel-defined memdesc doesn't "
439                            "match the one from EFI!\n");
440         }
441 #if EFI_DEBUG
442         print_efi_memmap();
443 #endif
444 }
445
446 /*
447  * This function will switch the EFI runtime services to virtual mode.
448  * Essentially, look through the EFI memmap and map every region that
449  * has the runtime attribute bit set in its memory descriptor and update
450  * that memory descriptor with the virtual address obtained from ioremap().
451  * This enables the runtime services to be called without having to
452  * thunk back into physical mode for every invocation.
453  */
454
455 void __init efi_enter_virtual_mode(void)
456 {
457         efi_memory_desc_t *md;
458         efi_status_t status;
459         int i;
460
461         efi.systab = NULL;
462
463         for (i = 0; i < memmap.nr_map; i++) {
464                 md = &memmap.map[i];
465
466                 if (md->attribute & EFI_MEMORY_RUNTIME) {
467                         md->virt_addr =
468                                 (unsigned long)ioremap(md->phys_addr,
469                                         md->num_pages << EFI_PAGE_SHIFT);
470                         if (!(unsigned long)md->virt_addr) {
471                                 printk(KERN_ERR PFX "ioremap of 0x%lX failed\n",
472                                         (unsigned long)md->phys_addr);
473                         }
474
475                         if (((unsigned long)md->phys_addr <=
476                                         (unsigned long)efi_phys.systab) &&
477                                 ((unsigned long)efi_phys.systab <
478                                         md->phys_addr +
479                                         ((unsigned long)md->num_pages <<
480                                                 EFI_PAGE_SHIFT))) {
481                                 unsigned long addr;
482
483                                 addr = md->virt_addr - md->phys_addr +
484                                                 (unsigned long)efi_phys.systab;
485                                 efi.systab = (efi_system_table_t *)addr;
486                         }
487                 }
488         }
489
490         if (!efi.systab)
491                 BUG();
492
493         status = phys_efi_set_virtual_address_map(
494                         sizeof(efi_memory_desc_t) * memmap.nr_map,
495                         sizeof(efi_memory_desc_t),
496                         memmap.desc_version,
497                         memmap.phys_map);
498
499         if (status != EFI_SUCCESS) {
500                 printk (KERN_ALERT "You are screwed! "
501                         "Unable to switch EFI into virtual mode "
502                         "(status=%lx)\n", status);
503                 panic("EFI call to SetVirtualAddressMap() failed!");
504         }
505
506         /*
507          * Now that EFI is in virtual mode, update the function
508          * pointers in the runtime service table to the new virtual addresses.
509          */
510
511         efi.get_time = (efi_get_time_t *) efi.systab->runtime->get_time;
512         efi.set_time = (efi_set_time_t *) efi.systab->runtime->set_time;
513         efi.get_wakeup_time = (efi_get_wakeup_time_t *)
514                                         efi.systab->runtime->get_wakeup_time;
515         efi.set_wakeup_time = (efi_set_wakeup_time_t *)
516                                         efi.systab->runtime->set_wakeup_time;
517         efi.get_variable = (efi_get_variable_t *)
518                                         efi.systab->runtime->get_variable;
519         efi.get_next_variable = (efi_get_next_variable_t *)
520                                         efi.systab->runtime->get_next_variable;
521         efi.set_variable = (efi_set_variable_t *)
522                                         efi.systab->runtime->set_variable;
523         efi.get_next_high_mono_count = (efi_get_next_high_mono_count_t *)
524                                         efi.systab->runtime->get_next_high_mono_count;
525         efi.reset_system = (efi_reset_system_t *)
526                                         efi.systab->runtime->reset_system;
527 }
528
529 void __init
530 efi_initialize_iomem_resources(struct resource *code_resource,
531                                struct resource *data_resource)
532 {
533         struct resource *res;
534         efi_memory_desc_t *md;
535         int i;
536
537         for (i = 0; i < memmap.nr_map; i++) {
538                 md = &memmap.map[i];
539
540                 if ((md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)) >
541                     0x100000000ULL)
542                         continue;
543                 res = alloc_bootmem_low(sizeof(struct resource));
544                 switch (md->type) {
545                 case EFI_RESERVED_TYPE:
546                         res->name = "Reserved Memory";
547                         break;
548                 case EFI_LOADER_CODE:
549                         res->name = "Loader Code";
550                         break;
551                 case EFI_LOADER_DATA:
552                         res->name = "Loader Data";
553                         break;
554                 case EFI_BOOT_SERVICES_DATA:
555                         res->name = "BootServices Data";
556                         break;
557                 case EFI_BOOT_SERVICES_CODE:
558                         res->name = "BootServices Code";
559                         break;
560                 case EFI_RUNTIME_SERVICES_CODE:
561                         res->name = "Runtime Service Code";
562                         break;
563                 case EFI_RUNTIME_SERVICES_DATA:
564                         res->name = "Runtime Service Data";
565                         break;
566                 case EFI_CONVENTIONAL_MEMORY:
567                         res->name = "Conventional Memory";
568                         break;
569                 case EFI_UNUSABLE_MEMORY:
570                         res->name = "Unusable Memory";
571                         break;
572                 case EFI_ACPI_RECLAIM_MEMORY:
573                         res->name = "ACPI Reclaim";
574                         break;
575                 case EFI_ACPI_MEMORY_NVS:
576                         res->name = "ACPI NVS";
577                         break;
578                 case EFI_MEMORY_MAPPED_IO:
579                         res->name = "Memory Mapped IO";
580                         break;
581                 case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
582                         res->name = "Memory Mapped IO Port Space";
583                         break;
584                 default:
585                         res->name = "Reserved";
586                         break;
587                 }
588                 res->start = md->phys_addr;
589                 res->end = res->start + ((md->num_pages << EFI_PAGE_SHIFT) - 1);
590                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
591                 if (request_resource(&iomem_resource, res) < 0)
592                         printk(KERN_ERR PFX "Failed to allocate res %s : 0x%lx-0x%lx\n",
593                                 res->name, res->start, res->end);
594                 /*
595                  * We don't know which region contains kernel data so we try
596                  * it repeatedly and let the resource manager test it.
597                  */
598                 if (md->type == EFI_CONVENTIONAL_MEMORY) {
599                         request_resource(res, code_resource);
600                         request_resource(res, data_resource);
601                 }
602         }
603 }
604
605 /*
606  * Convenience functions to obtain memory types and attributes
607  */
608
609 u32 efi_mem_type(unsigned long phys_addr)
610 {
611         efi_memory_desc_t *md;
612         int i;
613
614         for (i = 0; i < memmap.nr_map; i++) {
615                 md = &memmap.map[i];
616                 if ((md->phys_addr <= phys_addr) && (phys_addr <
617                         (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
618                         return md->type;
619         }
620         return 0;
621 }
622
623 u64 efi_mem_attributes(unsigned long phys_addr)
624 {
625         efi_memory_desc_t *md;
626         int i;
627
628         for (i = 0; i < memmap.nr_map; i++) {
629                 md = &memmap.map[i];
630                 if ((md->phys_addr <= phys_addr) && (phys_addr <
631                         (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
632                         return md->attribute;
633         }
634         return 0;
635 }