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Remove obsolete #include <linux/config.h>
[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/kernel.h>
23 #include <linux/init.h>
24 #include <linux/mm.h>
25 #include <linux/types.h>
26 #include <linux/time.h>
27 #include <linux/spinlock.h>
28 #include <linux/bootmem.h>
29 #include <linux/ioport.h>
30 #include <linux/module.h>
31 #include <linux/efi.h>
32 #include <linux/kexec.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;
50 struct efi_memory_map memmap;
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         struct Xgt_desc_struct *cpu_gdt_descr;
73
74         spin_lock(&efi_rt_lock);
75         local_irq_save(efi_rt_eflags);
76
77         cpu_gdt_descr = &per_cpu(cpu_gdt_descr, 0);
78
79         /*
80          * If I don't have PSE, I should just duplicate two entries in page
81          * directory. If I have PSE, I just need to duplicate one entry in
82          * page directory.
83          */
84         cr4 = read_cr4();
85
86         if (cr4 & X86_CR4_PSE) {
87                 efi_bak_pg_dir_pointer[0].pgd =
88                     swapper_pg_dir[pgd_index(0)].pgd;
89                 swapper_pg_dir[0].pgd =
90                     swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
91         } else {
92                 efi_bak_pg_dir_pointer[0].pgd =
93                     swapper_pg_dir[pgd_index(0)].pgd;
94                 efi_bak_pg_dir_pointer[1].pgd =
95                     swapper_pg_dir[pgd_index(0x400000)].pgd;
96                 swapper_pg_dir[pgd_index(0)].pgd =
97                     swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
98                 temp = PAGE_OFFSET + 0x400000;
99                 swapper_pg_dir[pgd_index(0x400000)].pgd =
100                     swapper_pg_dir[pgd_index(temp)].pgd;
101         }
102
103         /*
104          * After the lock is released, the original page table is restored.
105          */
106         local_flush_tlb();
107
108         cpu_gdt_descr->address = __pa(cpu_gdt_descr->address);
109         load_gdt(cpu_gdt_descr);
110 }
111
112 static void efi_call_phys_epilog(void)
113 {
114         unsigned long cr4;
115         struct Xgt_desc_struct *cpu_gdt_descr = &per_cpu(cpu_gdt_descr, 0);
116
117         cpu_gdt_descr->address = (unsigned long)__va(cpu_gdt_descr->address);
118         load_gdt(cpu_gdt_descr);
119
120         cr4 = read_cr4();
121
122         if (cr4 & X86_CR4_PSE) {
123                 swapper_pg_dir[pgd_index(0)].pgd =
124                     efi_bak_pg_dir_pointer[0].pgd;
125         } else {
126                 swapper_pg_dir[pgd_index(0)].pgd =
127                     efi_bak_pg_dir_pointer[0].pgd;
128                 swapper_pg_dir[pgd_index(0x400000)].pgd =
129                     efi_bak_pg_dir_pointer[1].pgd;
130         }
131
132         /*
133          * After the lock is released, the original page table is restored.
134          */
135         local_flush_tlb();
136
137         local_irq_restore(efi_rt_eflags);
138         spin_unlock(&efi_rt_lock);
139 }
140
141 static efi_status_t
142 phys_efi_set_virtual_address_map(unsigned long memory_map_size,
143                                  unsigned long descriptor_size,
144                                  u32 descriptor_version,
145                                  efi_memory_desc_t *virtual_map)
146 {
147         efi_status_t status;
148
149         efi_call_phys_prelog();
150         status = efi_call_phys(efi_phys.set_virtual_address_map,
151                                      memory_map_size, descriptor_size,
152                                      descriptor_version, virtual_map);
153         efi_call_phys_epilog();
154         return status;
155 }
156
157 static efi_status_t
158 phys_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
159 {
160         efi_status_t status;
161
162         efi_call_phys_prelog();
163         status = efi_call_phys(efi_phys.get_time, tm, tc);
164         efi_call_phys_epilog();
165         return status;
166 }
167
168 inline int efi_set_rtc_mmss(unsigned long nowtime)
169 {
170         int real_seconds, real_minutes;
171         efi_status_t    status;
172         efi_time_t      eft;
173         efi_time_cap_t  cap;
174
175         spin_lock(&efi_rt_lock);
176         status = efi.get_time(&eft, &cap);
177         spin_unlock(&efi_rt_lock);
178         if (status != EFI_SUCCESS)
179                 panic("Ooops, efitime: can't read time!\n");
180         real_seconds = nowtime % 60;
181         real_minutes = nowtime / 60;
182
183         if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
184                 real_minutes += 30;
185         real_minutes %= 60;
186
187         eft.minute = real_minutes;
188         eft.second = real_seconds;
189
190         if (status != EFI_SUCCESS) {
191                 printk("Ooops: efitime: can't read time!\n");
192                 return -1;
193         }
194         return 0;
195 }
196 /*
197  * This should only be used during kernel init and before runtime
198  * services have been remapped, therefore, we'll need to call in physical
199  * mode.  Note, this call isn't used later, so mark it __init.
200  */
201 inline unsigned long __init efi_get_time(void)
202 {
203         efi_status_t status;
204         efi_time_t eft;
205         efi_time_cap_t cap;
206
207         status = phys_efi_get_time(&eft, &cap);
208         if (status != EFI_SUCCESS)
209                 printk("Oops: efitime: can't read time status: 0x%lx\n",status);
210
211         return mktime(eft.year, eft.month, eft.day, eft.hour,
212                         eft.minute, eft.second);
213 }
214
215 int is_available_memory(efi_memory_desc_t * md)
216 {
217         if (!(md->attribute & EFI_MEMORY_WB))
218                 return 0;
219
220         switch (md->type) {
221                 case EFI_LOADER_CODE:
222                 case EFI_LOADER_DATA:
223                 case EFI_BOOT_SERVICES_CODE:
224                 case EFI_BOOT_SERVICES_DATA:
225                 case EFI_CONVENTIONAL_MEMORY:
226                         return 1;
227         }
228         return 0;
229 }
230
231 /*
232  * We need to map the EFI memory map again after paging_init().
233  */
234 void __init efi_map_memmap(void)
235 {
236         memmap.map = NULL;
237
238         memmap.map = bt_ioremap((unsigned long) memmap.phys_map,
239                         (memmap.nr_map * memmap.desc_size));
240         if (memmap.map == NULL)
241                 printk(KERN_ERR PFX "Could not remap the EFI memmap!\n");
242
243         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
244 }
245
246 #if EFI_DEBUG
247 static void __init print_efi_memmap(void)
248 {
249         efi_memory_desc_t *md;
250         void *p;
251         int i;
252
253         for (p = memmap.map, i = 0; p < memmap.map_end; p += memmap.desc_size, i++) {
254                 md = p;
255                 printk(KERN_INFO "mem%02u: type=%u, attr=0x%llx, "
256                         "range=[0x%016llx-0x%016llx) (%lluMB)\n",
257                         i, md->type, md->attribute, md->phys_addr,
258                         md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
259                         (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
260         }
261 }
262 #endif  /*  EFI_DEBUG  */
263
264 /*
265  * Walks the EFI memory map and calls CALLBACK once for each EFI
266  * memory descriptor that has memory that is available for kernel use.
267  */
268 void efi_memmap_walk(efi_freemem_callback_t callback, void *arg)
269 {
270         int prev_valid = 0;
271         struct range {
272                 unsigned long start;
273                 unsigned long end;
274         } prev, curr;
275         efi_memory_desc_t *md;
276         unsigned long start, end;
277         void *p;
278
279         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
280                 md = p;
281
282                 if ((md->num_pages == 0) || (!is_available_memory(md)))
283                         continue;
284
285                 curr.start = md->phys_addr;
286                 curr.end = curr.start + (md->num_pages << EFI_PAGE_SHIFT);
287
288                 if (!prev_valid) {
289                         prev = curr;
290                         prev_valid = 1;
291                 } else {
292                         if (curr.start < prev.start)
293                                 printk(KERN_INFO PFX "Unordered memory map\n");
294                         if (prev.end == curr.start)
295                                 prev.end = curr.end;
296                         else {
297                                 start =
298                                     (unsigned long) (PAGE_ALIGN(prev.start));
299                                 end = (unsigned long) (prev.end & PAGE_MASK);
300                                 if ((end > start)
301                                     && (*callback) (start, end, arg) < 0)
302                                         return;
303                                 prev = curr;
304                         }
305                 }
306         }
307         if (prev_valid) {
308                 start = (unsigned long) PAGE_ALIGN(prev.start);
309                 end = (unsigned long) (prev.end & PAGE_MASK);
310                 if (end > start)
311                         (*callback) (start, end, arg);
312         }
313 }
314
315 void __init efi_init(void)
316 {
317         efi_config_table_t *config_tables;
318         efi_runtime_services_t *runtime;
319         efi_char16_t *c16;
320         char vendor[100] = "unknown";
321         unsigned long num_config_tables;
322         int i = 0;
323
324         memset(&efi, 0, sizeof(efi) );
325         memset(&efi_phys, 0, sizeof(efi_phys));
326
327         efi_phys.systab = EFI_SYSTAB;
328         memmap.phys_map = EFI_MEMMAP;
329         memmap.nr_map = EFI_MEMMAP_SIZE/EFI_MEMDESC_SIZE;
330         memmap.desc_version = EFI_MEMDESC_VERSION;
331         memmap.desc_size = EFI_MEMDESC_SIZE;
332
333         efi.systab = (efi_system_table_t *)
334                 boot_ioremap((unsigned long) efi_phys.systab,
335                         sizeof(efi_system_table_t));
336         /*
337          * Verify the EFI Table
338          */
339         if (efi.systab == NULL)
340                 printk(KERN_ERR PFX "Woah! Couldn't map the EFI system table.\n");
341         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
342                 printk(KERN_ERR PFX "Woah! EFI system table signature incorrect\n");
343         if ((efi.systab->hdr.revision ^ EFI_SYSTEM_TABLE_REVISION) >> 16 != 0)
344                 printk(KERN_ERR PFX
345                        "Warning: EFI system table major version mismatch: "
346                        "got %d.%02d, expected %d.%02d\n",
347                        efi.systab->hdr.revision >> 16,
348                        efi.systab->hdr.revision & 0xffff,
349                        EFI_SYSTEM_TABLE_REVISION >> 16,
350                        EFI_SYSTEM_TABLE_REVISION & 0xffff);
351         /*
352          * Grab some details from the system table
353          */
354         num_config_tables = efi.systab->nr_tables;
355         config_tables = (efi_config_table_t *)efi.systab->tables;
356         runtime = efi.systab->runtime;
357
358         /*
359          * Show what we know for posterity
360          */
361         c16 = (efi_char16_t *) boot_ioremap(efi.systab->fw_vendor, 2);
362         if (c16) {
363                 for (i = 0; i < (sizeof(vendor) - 1) && *c16; ++i)
364                         vendor[i] = *c16++;
365                 vendor[i] = '\0';
366         } else
367                 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
368
369         printk(KERN_INFO PFX "EFI v%u.%.02u by %s \n",
370                efi.systab->hdr.revision >> 16,
371                efi.systab->hdr.revision & 0xffff, vendor);
372
373         /*
374          * Let's see what config tables the firmware passed to us.
375          */
376         config_tables = (efi_config_table_t *)
377                                 boot_ioremap((unsigned long) config_tables,
378                                 num_config_tables * sizeof(efi_config_table_t));
379
380         if (config_tables == NULL)
381                 printk(KERN_ERR PFX "Could not map EFI Configuration Table!\n");
382
383         efi.mps        = EFI_INVALID_TABLE_ADDR;
384         efi.acpi       = EFI_INVALID_TABLE_ADDR;
385         efi.acpi20     = EFI_INVALID_TABLE_ADDR;
386         efi.smbios     = EFI_INVALID_TABLE_ADDR;
387         efi.sal_systab = EFI_INVALID_TABLE_ADDR;
388         efi.boot_info  = EFI_INVALID_TABLE_ADDR;
389         efi.hcdp       = EFI_INVALID_TABLE_ADDR;
390         efi.uga        = EFI_INVALID_TABLE_ADDR;
391
392         for (i = 0; i < num_config_tables; i++) {
393                 if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
394                         efi.mps = config_tables[i].table;
395                         printk(KERN_INFO " MPS=0x%lx ", config_tables[i].table);
396                 } else
397                     if (efi_guidcmp(config_tables[i].guid, ACPI_20_TABLE_GUID) == 0) {
398                         efi.acpi20 = config_tables[i].table;
399                         printk(KERN_INFO " ACPI 2.0=0x%lx ", config_tables[i].table);
400                 } else
401                     if (efi_guidcmp(config_tables[i].guid, ACPI_TABLE_GUID) == 0) {
402                         efi.acpi = config_tables[i].table;
403                         printk(KERN_INFO " ACPI=0x%lx ", config_tables[i].table);
404                 } else
405                     if (efi_guidcmp(config_tables[i].guid, SMBIOS_TABLE_GUID) == 0) {
406                         efi.smbios = config_tables[i].table;
407                         printk(KERN_INFO " SMBIOS=0x%lx ", config_tables[i].table);
408                 } else
409                     if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
410                         efi.hcdp = config_tables[i].table;
411                         printk(KERN_INFO " HCDP=0x%lx ", config_tables[i].table);
412                 } else
413                     if (efi_guidcmp(config_tables[i].guid, UGA_IO_PROTOCOL_GUID) == 0) {
414                         efi.uga = config_tables[i].table;
415                         printk(KERN_INFO " UGA=0x%lx ", config_tables[i].table);
416                 }
417         }
418         printk("\n");
419
420         /*
421          * Check out the runtime services table. We need to map
422          * the runtime services table so that we can grab the physical
423          * address of several of the EFI runtime functions, needed to
424          * set the firmware into virtual mode.
425          */
426
427         runtime = (efi_runtime_services_t *) boot_ioremap((unsigned long)
428                                                 runtime,
429                                                 sizeof(efi_runtime_services_t));
430         if (runtime != NULL) {
431                 /*
432                  * We will only need *early* access to the following
433                  * two EFI runtime services before set_virtual_address_map
434                  * is invoked.
435                  */
436                 efi_phys.get_time = (efi_get_time_t *) runtime->get_time;
437                 efi_phys.set_virtual_address_map =
438                         (efi_set_virtual_address_map_t *)
439                                 runtime->set_virtual_address_map;
440         } else
441                 printk(KERN_ERR PFX "Could not map the runtime service table!\n");
442
443         /* Map the EFI memory map for use until paging_init() */
444         memmap.map = boot_ioremap((unsigned long) EFI_MEMMAP, EFI_MEMMAP_SIZE);
445         if (memmap.map == NULL)
446                 printk(KERN_ERR PFX "Could not map the EFI memory map!\n");
447
448         memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
449
450 #if EFI_DEBUG
451         print_efi_memmap();
452 #endif
453 }
454
455 static inline void __init check_range_for_systab(efi_memory_desc_t *md)
456 {
457         if (((unsigned long)md->phys_addr <= (unsigned long)efi_phys.systab) &&
458                 ((unsigned long)efi_phys.systab < md->phys_addr +
459                 ((unsigned long)md->num_pages << EFI_PAGE_SHIFT))) {
460                 unsigned long addr;
461
462                 addr = md->virt_addr - md->phys_addr +
463                         (unsigned long)efi_phys.systab;
464                 efi.systab = (efi_system_table_t *)addr;
465         }
466 }
467
468 /*
469  * This function will switch the EFI runtime services to virtual mode.
470  * Essentially, look through the EFI memmap and map every region that
471  * has the runtime attribute bit set in its memory descriptor and update
472  * that memory descriptor with the virtual address obtained from ioremap().
473  * This enables the runtime services to be called without having to
474  * thunk back into physical mode for every invocation.
475  */
476
477 void __init efi_enter_virtual_mode(void)
478 {
479         efi_memory_desc_t *md;
480         efi_status_t status;
481         void *p;
482
483         efi.systab = NULL;
484
485         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
486                 md = p;
487
488                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
489                         continue;
490
491                 md->virt_addr = (unsigned long)ioremap(md->phys_addr,
492                         md->num_pages << EFI_PAGE_SHIFT);
493                 if (!(unsigned long)md->virt_addr) {
494                         printk(KERN_ERR PFX "ioremap of 0x%lX failed\n",
495                                 (unsigned long)md->phys_addr);
496                 }
497                 /* update the virtual address of the EFI system table */
498                 check_range_for_systab(md);
499         }
500
501         if (!efi.systab)
502                 BUG();
503
504         status = phys_efi_set_virtual_address_map(
505                         memmap.desc_size * memmap.nr_map,
506                         memmap.desc_size,
507                         memmap.desc_version,
508                         memmap.phys_map);
509
510         if (status != EFI_SUCCESS) {
511                 printk (KERN_ALERT "You are screwed! "
512                         "Unable to switch EFI into virtual mode "
513                         "(status=%lx)\n", status);
514                 panic("EFI call to SetVirtualAddressMap() failed!");
515         }
516
517         /*
518          * Now that EFI is in virtual mode, update the function
519          * pointers in the runtime service table to the new virtual addresses.
520          */
521
522         efi.get_time = (efi_get_time_t *) efi.systab->runtime->get_time;
523         efi.set_time = (efi_set_time_t *) efi.systab->runtime->set_time;
524         efi.get_wakeup_time = (efi_get_wakeup_time_t *)
525                                         efi.systab->runtime->get_wakeup_time;
526         efi.set_wakeup_time = (efi_set_wakeup_time_t *)
527                                         efi.systab->runtime->set_wakeup_time;
528         efi.get_variable = (efi_get_variable_t *)
529                                         efi.systab->runtime->get_variable;
530         efi.get_next_variable = (efi_get_next_variable_t *)
531                                         efi.systab->runtime->get_next_variable;
532         efi.set_variable = (efi_set_variable_t *)
533                                         efi.systab->runtime->set_variable;
534         efi.get_next_high_mono_count = (efi_get_next_high_mono_count_t *)
535                                         efi.systab->runtime->get_next_high_mono_count;
536         efi.reset_system = (efi_reset_system_t *)
537                                         efi.systab->runtime->reset_system;
538 }
539
540 void __init
541 efi_initialize_iomem_resources(struct resource *code_resource,
542                                struct resource *data_resource)
543 {
544         struct resource *res;
545         efi_memory_desc_t *md;
546         void *p;
547
548         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
549                 md = p;
550
551                 if ((md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)) >
552                     0x100000000ULL)
553                         continue;
554                 res = kzalloc(sizeof(struct resource), GFP_ATOMIC);
555                 switch (md->type) {
556                 case EFI_RESERVED_TYPE:
557                         res->name = "Reserved Memory";
558                         break;
559                 case EFI_LOADER_CODE:
560                         res->name = "Loader Code";
561                         break;
562                 case EFI_LOADER_DATA:
563                         res->name = "Loader Data";
564                         break;
565                 case EFI_BOOT_SERVICES_DATA:
566                         res->name = "BootServices Data";
567                         break;
568                 case EFI_BOOT_SERVICES_CODE:
569                         res->name = "BootServices Code";
570                         break;
571                 case EFI_RUNTIME_SERVICES_CODE:
572                         res->name = "Runtime Service Code";
573                         break;
574                 case EFI_RUNTIME_SERVICES_DATA:
575                         res->name = "Runtime Service Data";
576                         break;
577                 case EFI_CONVENTIONAL_MEMORY:
578                         res->name = "Conventional Memory";
579                         break;
580                 case EFI_UNUSABLE_MEMORY:
581                         res->name = "Unusable Memory";
582                         break;
583                 case EFI_ACPI_RECLAIM_MEMORY:
584                         res->name = "ACPI Reclaim";
585                         break;
586                 case EFI_ACPI_MEMORY_NVS:
587                         res->name = "ACPI NVS";
588                         break;
589                 case EFI_MEMORY_MAPPED_IO:
590                         res->name = "Memory Mapped IO";
591                         break;
592                 case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
593                         res->name = "Memory Mapped IO Port Space";
594                         break;
595                 default:
596                         res->name = "Reserved";
597                         break;
598                 }
599                 res->start = md->phys_addr;
600                 res->end = res->start + ((md->num_pages << EFI_PAGE_SHIFT) - 1);
601                 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
602                 if (request_resource(&iomem_resource, res) < 0)
603                         printk(KERN_ERR PFX "Failed to allocate res %s : "
604                                 "0x%llx-0x%llx\n", res->name,
605                                 (unsigned long long)res->start,
606                                 (unsigned long long)res->end);
607                 /*
608                  * We don't know which region contains kernel data so we try
609                  * it repeatedly and let the resource manager test it.
610                  */
611                 if (md->type == EFI_CONVENTIONAL_MEMORY) {
612                         request_resource(res, code_resource);
613                         request_resource(res, data_resource);
614 #ifdef CONFIG_KEXEC
615                         request_resource(res, &crashk_res);
616 #endif
617                 }
618         }
619 }
620
621 /*
622  * Convenience functions to obtain memory types and attributes
623  */
624
625 u32 efi_mem_type(unsigned long phys_addr)
626 {
627         efi_memory_desc_t *md;
628         void *p;
629
630         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
631                 md = p;
632                 if ((md->phys_addr <= phys_addr) && (phys_addr <
633                         (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
634                         return md->type;
635         }
636         return 0;
637 }
638
639 u64 efi_mem_attributes(unsigned long phys_addr)
640 {
641         efi_memory_desc_t *md;
642         void *p;
643
644         for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
645                 md = p;
646                 if ((md->phys_addr <= phys_addr) && (phys_addr <
647                         (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
648                         return md->attribute;
649         }
650         return 0;
651 }