Merge tag 'for-5.4/io_uring-2019-09-27' of git://git.kernel.dk/linux-block
[linux-2.6-microblaze.git] / arch / ia64 / kernel / efi.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Extensible Firmware Interface
4  *
5  * Based on Extensible Firmware Interface Specification version 0.9
6  * April 30, 1999
7  *
8  * Copyright (C) 1999 VA Linux Systems
9  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
10  * Copyright (C) 1999-2003 Hewlett-Packard Co.
11  *      David Mosberger-Tang <davidm@hpl.hp.com>
12  *      Stephane Eranian <eranian@hpl.hp.com>
13  * (c) Copyright 2006 Hewlett-Packard Development Company, L.P.
14  *      Bjorn Helgaas <bjorn.helgaas@hp.com>
15  *
16  * All EFI Runtime Services are not implemented yet as EFI only
17  * supports physical mode addressing on SoftSDV. This is to be fixed
18  * in a future version.  --drummond 1999-07-20
19  *
20  * Implemented EFI runtime services and virtual mode calls.  --davidm
21  *
22  * Goutham Rao: <goutham.rao@intel.com>
23  *      Skip non-WB memory and ignore empty memory ranges.
24  */
25 #include <linux/module.h>
26 #include <linux/memblock.h>
27 #include <linux/crash_dump.h>
28 #include <linux/kernel.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/slab.h>
32 #include <linux/time.h>
33 #include <linux/efi.h>
34 #include <linux/kexec.h>
35 #include <linux/mm.h>
36
37 #include <asm/io.h>
38 #include <asm/kregs.h>
39 #include <asm/meminit.h>
40 #include <asm/pgtable.h>
41 #include <asm/processor.h>
42 #include <asm/mca.h>
43 #include <asm/setup.h>
44 #include <asm/tlbflush.h>
45
46 #define EFI_DEBUG       0
47
48 static __initdata unsigned long palo_phys;
49
50 unsigned long sal_systab_phys = EFI_INVALID_TABLE_ADDR;
51
52 static __initdata efi_config_table_type_t arch_tables[] = {
53         {PROCESSOR_ABSTRACTION_LAYER_OVERWRITE_GUID, "PALO", &palo_phys},
54         {SAL_SYSTEM_TABLE_GUID, "SALsystab", &sal_systab_phys},
55         {NULL_GUID, NULL, 0},
56 };
57
58 extern efi_status_t efi_call_phys (void *, ...);
59
60 static efi_runtime_services_t *runtime;
61 static u64 mem_limit = ~0UL, max_addr = ~0UL, min_addr = 0UL;
62
63 #define efi_call_virt(f, args...)       (*(f))(args)
64
65 #define STUB_GET_TIME(prefix, adjust_arg)                                      \
66 static efi_status_t                                                            \
67 prefix##_get_time (efi_time_t *tm, efi_time_cap_t *tc)                         \
68 {                                                                              \
69         struct ia64_fpreg fr[6];                                               \
70         efi_time_cap_t *atc = NULL;                                            \
71         efi_status_t ret;                                                      \
72                                                                                \
73         if (tc)                                                                \
74                 atc = adjust_arg(tc);                                          \
75         ia64_save_scratch_fpregs(fr);                                          \
76         ret = efi_call_##prefix((efi_get_time_t *) __va(runtime->get_time),    \
77                                 adjust_arg(tm), atc);                          \
78         ia64_load_scratch_fpregs(fr);                                          \
79         return ret;                                                            \
80 }
81
82 #define STUB_SET_TIME(prefix, adjust_arg)                                      \
83 static efi_status_t                                                            \
84 prefix##_set_time (efi_time_t *tm)                                             \
85 {                                                                              \
86         struct ia64_fpreg fr[6];                                               \
87         efi_status_t ret;                                                      \
88                                                                                \
89         ia64_save_scratch_fpregs(fr);                                          \
90         ret = efi_call_##prefix((efi_set_time_t *) __va(runtime->set_time),    \
91                                 adjust_arg(tm));                               \
92         ia64_load_scratch_fpregs(fr);                                          \
93         return ret;                                                            \
94 }
95
96 #define STUB_GET_WAKEUP_TIME(prefix, adjust_arg)                               \
97 static efi_status_t                                                            \
98 prefix##_get_wakeup_time (efi_bool_t *enabled, efi_bool_t *pending,            \
99                           efi_time_t *tm)                                      \
100 {                                                                              \
101         struct ia64_fpreg fr[6];                                               \
102         efi_status_t ret;                                                      \
103                                                                                \
104         ia64_save_scratch_fpregs(fr);                                          \
105         ret = efi_call_##prefix(                                               \
106                 (efi_get_wakeup_time_t *) __va(runtime->get_wakeup_time),      \
107                 adjust_arg(enabled), adjust_arg(pending), adjust_arg(tm));     \
108         ia64_load_scratch_fpregs(fr);                                          \
109         return ret;                                                            \
110 }
111
112 #define STUB_SET_WAKEUP_TIME(prefix, adjust_arg)                               \
113 static efi_status_t                                                            \
114 prefix##_set_wakeup_time (efi_bool_t enabled, efi_time_t *tm)                  \
115 {                                                                              \
116         struct ia64_fpreg fr[6];                                               \
117         efi_time_t *atm = NULL;                                                \
118         efi_status_t ret;                                                      \
119                                                                                \
120         if (tm)                                                                \
121                 atm = adjust_arg(tm);                                          \
122         ia64_save_scratch_fpregs(fr);                                          \
123         ret = efi_call_##prefix(                                               \
124                 (efi_set_wakeup_time_t *) __va(runtime->set_wakeup_time),      \
125                 enabled, atm);                                                 \
126         ia64_load_scratch_fpregs(fr);                                          \
127         return ret;                                                            \
128 }
129
130 #define STUB_GET_VARIABLE(prefix, adjust_arg)                                  \
131 static efi_status_t                                                            \
132 prefix##_get_variable (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,      \
133                        unsigned long *data_size, void *data)                   \
134 {                                                                              \
135         struct ia64_fpreg fr[6];                                               \
136         u32 *aattr = NULL;                                                     \
137         efi_status_t ret;                                                      \
138                                                                                \
139         if (attr)                                                              \
140                 aattr = adjust_arg(attr);                                      \
141         ia64_save_scratch_fpregs(fr);                                          \
142         ret = efi_call_##prefix(                                               \
143                 (efi_get_variable_t *) __va(runtime->get_variable),            \
144                 adjust_arg(name), adjust_arg(vendor), aattr,                   \
145                 adjust_arg(data_size), adjust_arg(data));                      \
146         ia64_load_scratch_fpregs(fr);                                          \
147         return ret;                                                            \
148 }
149
150 #define STUB_GET_NEXT_VARIABLE(prefix, adjust_arg)                             \
151 static efi_status_t                                                            \
152 prefix##_get_next_variable (unsigned long *name_size, efi_char16_t *name,      \
153                             efi_guid_t *vendor)                                \
154 {                                                                              \
155         struct ia64_fpreg fr[6];                                               \
156         efi_status_t ret;                                                      \
157                                                                                \
158         ia64_save_scratch_fpregs(fr);                                          \
159         ret = efi_call_##prefix(                                               \
160                 (efi_get_next_variable_t *) __va(runtime->get_next_variable),  \
161                 adjust_arg(name_size), adjust_arg(name), adjust_arg(vendor));  \
162         ia64_load_scratch_fpregs(fr);                                          \
163         return ret;                                                            \
164 }
165
166 #define STUB_SET_VARIABLE(prefix, adjust_arg)                                  \
167 static efi_status_t                                                            \
168 prefix##_set_variable (efi_char16_t *name, efi_guid_t *vendor,                 \
169                        u32 attr, unsigned long data_size,                      \
170                        void *data)                                             \
171 {                                                                              \
172         struct ia64_fpreg fr[6];                                               \
173         efi_status_t ret;                                                      \
174                                                                                \
175         ia64_save_scratch_fpregs(fr);                                          \
176         ret = efi_call_##prefix(                                               \
177                 (efi_set_variable_t *) __va(runtime->set_variable),            \
178                 adjust_arg(name), adjust_arg(vendor), attr, data_size,         \
179                 adjust_arg(data));                                             \
180         ia64_load_scratch_fpregs(fr);                                          \
181         return ret;                                                            \
182 }
183
184 #define STUB_GET_NEXT_HIGH_MONO_COUNT(prefix, adjust_arg)                      \
185 static efi_status_t                                                            \
186 prefix##_get_next_high_mono_count (u32 *count)                                 \
187 {                                                                              \
188         struct ia64_fpreg fr[6];                                               \
189         efi_status_t ret;                                                      \
190                                                                                \
191         ia64_save_scratch_fpregs(fr);                                          \
192         ret = efi_call_##prefix((efi_get_next_high_mono_count_t *)             \
193                                 __va(runtime->get_next_high_mono_count),       \
194                                 adjust_arg(count));                            \
195         ia64_load_scratch_fpregs(fr);                                          \
196         return ret;                                                            \
197 }
198
199 #define STUB_RESET_SYSTEM(prefix, adjust_arg)                                  \
200 static void                                                                    \
201 prefix##_reset_system (int reset_type, efi_status_t status,                    \
202                        unsigned long data_size, efi_char16_t *data)            \
203 {                                                                              \
204         struct ia64_fpreg fr[6];                                               \
205         efi_char16_t *adata = NULL;                                            \
206                                                                                \
207         if (data)                                                              \
208                 adata = adjust_arg(data);                                      \
209                                                                                \
210         ia64_save_scratch_fpregs(fr);                                          \
211         efi_call_##prefix(                                                     \
212                 (efi_reset_system_t *) __va(runtime->reset_system),            \
213                 reset_type, status, data_size, adata);                         \
214         /* should not return, but just in case... */                           \
215         ia64_load_scratch_fpregs(fr);                                          \
216 }
217
218 #define phys_ptr(arg)   ((__typeof__(arg)) ia64_tpa(arg))
219
220 STUB_GET_TIME(phys, phys_ptr)
221 STUB_SET_TIME(phys, phys_ptr)
222 STUB_GET_WAKEUP_TIME(phys, phys_ptr)
223 STUB_SET_WAKEUP_TIME(phys, phys_ptr)
224 STUB_GET_VARIABLE(phys, phys_ptr)
225 STUB_GET_NEXT_VARIABLE(phys, phys_ptr)
226 STUB_SET_VARIABLE(phys, phys_ptr)
227 STUB_GET_NEXT_HIGH_MONO_COUNT(phys, phys_ptr)
228 STUB_RESET_SYSTEM(phys, phys_ptr)
229
230 #define id(arg) arg
231
232 STUB_GET_TIME(virt, id)
233 STUB_SET_TIME(virt, id)
234 STUB_GET_WAKEUP_TIME(virt, id)
235 STUB_SET_WAKEUP_TIME(virt, id)
236 STUB_GET_VARIABLE(virt, id)
237 STUB_GET_NEXT_VARIABLE(virt, id)
238 STUB_SET_VARIABLE(virt, id)
239 STUB_GET_NEXT_HIGH_MONO_COUNT(virt, id)
240 STUB_RESET_SYSTEM(virt, id)
241
242 void
243 efi_gettimeofday (struct timespec64 *ts)
244 {
245         efi_time_t tm;
246
247         if ((*efi.get_time)(&tm, NULL) != EFI_SUCCESS) {
248                 memset(ts, 0, sizeof(*ts));
249                 return;
250         }
251
252         ts->tv_sec = mktime64(tm.year, tm.month, tm.day,
253                             tm.hour, tm.minute, tm.second);
254         ts->tv_nsec = tm.nanosecond;
255 }
256
257 static int
258 is_memory_available (efi_memory_desc_t *md)
259 {
260         if (!(md->attribute & EFI_MEMORY_WB))
261                 return 0;
262
263         switch (md->type) {
264               case EFI_LOADER_CODE:
265               case EFI_LOADER_DATA:
266               case EFI_BOOT_SERVICES_CODE:
267               case EFI_BOOT_SERVICES_DATA:
268               case EFI_CONVENTIONAL_MEMORY:
269                 return 1;
270         }
271         return 0;
272 }
273
274 typedef struct kern_memdesc {
275         u64 attribute;
276         u64 start;
277         u64 num_pages;
278 } kern_memdesc_t;
279
280 static kern_memdesc_t *kern_memmap;
281
282 #define efi_md_size(md) (md->num_pages << EFI_PAGE_SHIFT)
283
284 static inline u64
285 kmd_end(kern_memdesc_t *kmd)
286 {
287         return (kmd->start + (kmd->num_pages << EFI_PAGE_SHIFT));
288 }
289
290 static inline u64
291 efi_md_end(efi_memory_desc_t *md)
292 {
293         return (md->phys_addr + efi_md_size(md));
294 }
295
296 static inline int
297 efi_wb(efi_memory_desc_t *md)
298 {
299         return (md->attribute & EFI_MEMORY_WB);
300 }
301
302 static inline int
303 efi_uc(efi_memory_desc_t *md)
304 {
305         return (md->attribute & EFI_MEMORY_UC);
306 }
307
308 static void
309 walk (efi_freemem_callback_t callback, void *arg, u64 attr)
310 {
311         kern_memdesc_t *k;
312         u64 start, end, voff;
313
314         voff = (attr == EFI_MEMORY_WB) ? PAGE_OFFSET : __IA64_UNCACHED_OFFSET;
315         for (k = kern_memmap; k->start != ~0UL; k++) {
316                 if (k->attribute != attr)
317                         continue;
318                 start = PAGE_ALIGN(k->start);
319                 end = (k->start + (k->num_pages << EFI_PAGE_SHIFT)) & PAGE_MASK;
320                 if (start < end)
321                         if ((*callback)(start + voff, end + voff, arg) < 0)
322                                 return;
323         }
324 }
325
326 /*
327  * Walk the EFI memory map and call CALLBACK once for each EFI memory
328  * descriptor that has memory that is available for OS use.
329  */
330 void
331 efi_memmap_walk (efi_freemem_callback_t callback, void *arg)
332 {
333         walk(callback, arg, EFI_MEMORY_WB);
334 }
335
336 /*
337  * Walk the EFI memory map and call CALLBACK once for each EFI memory
338  * descriptor that has memory that is available for uncached allocator.
339  */
340 void
341 efi_memmap_walk_uc (efi_freemem_callback_t callback, void *arg)
342 {
343         walk(callback, arg, EFI_MEMORY_UC);
344 }
345
346 /*
347  * Look for the PAL_CODE region reported by EFI and map it using an
348  * ITR to enable safe PAL calls in virtual mode.  See IA-64 Processor
349  * Abstraction Layer chapter 11 in ADAG
350  */
351 void *
352 efi_get_pal_addr (void)
353 {
354         void *efi_map_start, *efi_map_end, *p;
355         efi_memory_desc_t *md;
356         u64 efi_desc_size;
357         int pal_code_count = 0;
358         u64 vaddr, mask;
359
360         efi_map_start = __va(ia64_boot_param->efi_memmap);
361         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
362         efi_desc_size = ia64_boot_param->efi_memdesc_size;
363
364         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
365                 md = p;
366                 if (md->type != EFI_PAL_CODE)
367                         continue;
368
369                 if (++pal_code_count > 1) {
370                         printk(KERN_ERR "Too many EFI Pal Code memory ranges, "
371                                "dropped @ %llx\n", md->phys_addr);
372                         continue;
373                 }
374                 /*
375                  * The only ITLB entry in region 7 that is used is the one
376                  * installed by __start().  That entry covers a 64MB range.
377                  */
378                 mask  = ~((1 << KERNEL_TR_PAGE_SHIFT) - 1);
379                 vaddr = PAGE_OFFSET + md->phys_addr;
380
381                 /*
382                  * We must check that the PAL mapping won't overlap with the
383                  * kernel mapping.
384                  *
385                  * PAL code is guaranteed to be aligned on a power of 2 between
386                  * 4k and 256KB and that only one ITR is needed to map it. This
387                  * implies that the PAL code is always aligned on its size,
388                  * i.e., the closest matching page size supported by the TLB.
389                  * Therefore PAL code is guaranteed never to cross a 64MB unless
390                  * it is bigger than 64MB (very unlikely!).  So for now the
391                  * following test is enough to determine whether or not we need
392                  * a dedicated ITR for the PAL code.
393                  */
394                 if ((vaddr & mask) == (KERNEL_START & mask)) {
395                         printk(KERN_INFO "%s: no need to install ITR for PAL code\n",
396                                __func__);
397                         continue;
398                 }
399
400                 if (efi_md_size(md) > IA64_GRANULE_SIZE)
401                         panic("Whoa!  PAL code size bigger than a granule!");
402
403 #if EFI_DEBUG
404                 mask  = ~((1 << IA64_GRANULE_SHIFT) - 1);
405
406                 printk(KERN_INFO "CPU %d: mapping PAL code "
407                        "[0x%lx-0x%lx) into [0x%lx-0x%lx)\n",
408                        smp_processor_id(), md->phys_addr,
409                        md->phys_addr + efi_md_size(md),
410                        vaddr & mask, (vaddr & mask) + IA64_GRANULE_SIZE);
411 #endif
412                 return __va(md->phys_addr);
413         }
414         printk(KERN_WARNING "%s: no PAL-code memory-descriptor found\n",
415                __func__);
416         return NULL;
417 }
418
419
420 static u8 __init palo_checksum(u8 *buffer, u32 length)
421 {
422         u8 sum = 0;
423         u8 *end = buffer + length;
424
425         while (buffer < end)
426                 sum = (u8) (sum + *(buffer++));
427
428         return sum;
429 }
430
431 /*
432  * Parse and handle PALO table which is published at:
433  * http://www.dig64.org/home/DIG64_PALO_R1_0.pdf
434  */
435 static void __init handle_palo(unsigned long phys_addr)
436 {
437         struct palo_table *palo = __va(phys_addr);
438         u8  checksum;
439
440         if (strncmp(palo->signature, PALO_SIG, sizeof(PALO_SIG) - 1)) {
441                 printk(KERN_INFO "PALO signature incorrect.\n");
442                 return;
443         }
444
445         checksum = palo_checksum((u8 *)palo, palo->length);
446         if (checksum) {
447                 printk(KERN_INFO "PALO checksum incorrect.\n");
448                 return;
449         }
450
451         setup_ptcg_sem(palo->max_tlb_purges, NPTCG_FROM_PALO);
452 }
453
454 void
455 efi_map_pal_code (void)
456 {
457         void *pal_vaddr = efi_get_pal_addr ();
458         u64 psr;
459
460         if (!pal_vaddr)
461                 return;
462
463         /*
464          * Cannot write to CRx with PSR.ic=1
465          */
466         psr = ia64_clear_ic();
467         ia64_itr(0x1, IA64_TR_PALCODE,
468                  GRANULEROUNDDOWN((unsigned long) pal_vaddr),
469                  pte_val(pfn_pte(__pa(pal_vaddr) >> PAGE_SHIFT, PAGE_KERNEL)),
470                  IA64_GRANULE_SHIFT);
471         ia64_set_psr(psr);              /* restore psr */
472 }
473
474 void __init
475 efi_init (void)
476 {
477         void *efi_map_start, *efi_map_end;
478         efi_char16_t *c16;
479         u64 efi_desc_size;
480         char *cp, vendor[100] = "unknown";
481         int i;
482
483         set_bit(EFI_BOOT, &efi.flags);
484         set_bit(EFI_64BIT, &efi.flags);
485
486         /*
487          * It's too early to be able to use the standard kernel command line
488          * support...
489          */
490         for (cp = boot_command_line; *cp; ) {
491                 if (memcmp(cp, "mem=", 4) == 0) {
492                         mem_limit = memparse(cp + 4, &cp);
493                 } else if (memcmp(cp, "max_addr=", 9) == 0) {
494                         max_addr = GRANULEROUNDDOWN(memparse(cp + 9, &cp));
495                 } else if (memcmp(cp, "min_addr=", 9) == 0) {
496                         min_addr = GRANULEROUNDDOWN(memparse(cp + 9, &cp));
497                 } else {
498                         while (*cp != ' ' && *cp)
499                                 ++cp;
500                         while (*cp == ' ')
501                                 ++cp;
502                 }
503         }
504         if (min_addr != 0UL)
505                 printk(KERN_INFO "Ignoring memory below %lluMB\n",
506                        min_addr >> 20);
507         if (max_addr != ~0UL)
508                 printk(KERN_INFO "Ignoring memory above %lluMB\n",
509                        max_addr >> 20);
510
511         efi.systab = __va(ia64_boot_param->efi_systab);
512
513         /*
514          * Verify the EFI Table
515          */
516         if (efi.systab == NULL)
517                 panic("Whoa! Can't find EFI system table.\n");
518         if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
519                 panic("Whoa! EFI system table signature incorrect\n");
520         if ((efi.systab->hdr.revision >> 16) == 0)
521                 printk(KERN_WARNING "Warning: EFI system table version "
522                        "%d.%02d, expected 1.00 or greater\n",
523                        efi.systab->hdr.revision >> 16,
524                        efi.systab->hdr.revision & 0xffff);
525
526         /* Show what we know for posterity */
527         c16 = __va(efi.systab->fw_vendor);
528         if (c16) {
529                 for (i = 0;i < (int) sizeof(vendor) - 1 && *c16; ++i)
530                         vendor[i] = *c16++;
531                 vendor[i] = '\0';
532         }
533
534         printk(KERN_INFO "EFI v%u.%.02u by %s:",
535                efi.systab->hdr.revision >> 16,
536                efi.systab->hdr.revision & 0xffff, vendor);
537
538         palo_phys      = EFI_INVALID_TABLE_ADDR;
539
540         if (efi_config_init(arch_tables) != 0)
541                 return;
542
543         if (palo_phys != EFI_INVALID_TABLE_ADDR)
544                 handle_palo(palo_phys);
545
546         runtime = __va(efi.systab->runtime);
547         efi.get_time = phys_get_time;
548         efi.set_time = phys_set_time;
549         efi.get_wakeup_time = phys_get_wakeup_time;
550         efi.set_wakeup_time = phys_set_wakeup_time;
551         efi.get_variable = phys_get_variable;
552         efi.get_next_variable = phys_get_next_variable;
553         efi.set_variable = phys_set_variable;
554         efi.get_next_high_mono_count = phys_get_next_high_mono_count;
555         efi.reset_system = phys_reset_system;
556
557         efi_map_start = __va(ia64_boot_param->efi_memmap);
558         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
559         efi_desc_size = ia64_boot_param->efi_memdesc_size;
560
561 #if EFI_DEBUG
562         /* print EFI memory map: */
563         {
564                 efi_memory_desc_t *md;
565                 void *p;
566
567                 for (i = 0, p = efi_map_start; p < efi_map_end;
568                      ++i, p += efi_desc_size)
569                 {
570                         const char *unit;
571                         unsigned long size;
572                         char buf[64];
573
574                         md = p;
575                         size = md->num_pages << EFI_PAGE_SHIFT;
576
577                         if ((size >> 40) > 0) {
578                                 size >>= 40;
579                                 unit = "TB";
580                         } else if ((size >> 30) > 0) {
581                                 size >>= 30;
582                                 unit = "GB";
583                         } else if ((size >> 20) > 0) {
584                                 size >>= 20;
585                                 unit = "MB";
586                         } else {
587                                 size >>= 10;
588                                 unit = "KB";
589                         }
590
591                         printk("mem%02d: %s "
592                                "range=[0x%016lx-0x%016lx) (%4lu%s)\n",
593                                i, efi_md_typeattr_format(buf, sizeof(buf), md),
594                                md->phys_addr,
595                                md->phys_addr + efi_md_size(md), size, unit);
596                 }
597         }
598 #endif
599
600         efi_map_pal_code();
601         efi_enter_virtual_mode();
602 }
603
604 void
605 efi_enter_virtual_mode (void)
606 {
607         void *efi_map_start, *efi_map_end, *p;
608         efi_memory_desc_t *md;
609         efi_status_t status;
610         u64 efi_desc_size;
611
612         efi_map_start = __va(ia64_boot_param->efi_memmap);
613         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
614         efi_desc_size = ia64_boot_param->efi_memdesc_size;
615
616         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
617                 md = p;
618                 if (md->attribute & EFI_MEMORY_RUNTIME) {
619                         /*
620                          * Some descriptors have multiple bits set, so the
621                          * order of the tests is relevant.
622                          */
623                         if (md->attribute & EFI_MEMORY_WB) {
624                                 md->virt_addr = (u64) __va(md->phys_addr);
625                         } else if (md->attribute & EFI_MEMORY_UC) {
626                                 md->virt_addr = (u64) ioremap(md->phys_addr, 0);
627                         } else if (md->attribute & EFI_MEMORY_WC) {
628 #if 0
629                                 md->virt_addr = ia64_remap(md->phys_addr,
630                                                            (_PAGE_A |
631                                                             _PAGE_P |
632                                                             _PAGE_D |
633                                                             _PAGE_MA_WC |
634                                                             _PAGE_PL_0 |
635                                                             _PAGE_AR_RW));
636 #else
637                                 printk(KERN_INFO "EFI_MEMORY_WC mapping\n");
638                                 md->virt_addr = (u64) ioremap(md->phys_addr, 0);
639 #endif
640                         } else if (md->attribute & EFI_MEMORY_WT) {
641 #if 0
642                                 md->virt_addr = ia64_remap(md->phys_addr,
643                                                            (_PAGE_A |
644                                                             _PAGE_P |
645                                                             _PAGE_D |
646                                                             _PAGE_MA_WT |
647                                                             _PAGE_PL_0 |
648                                                             _PAGE_AR_RW));
649 #else
650                                 printk(KERN_INFO "EFI_MEMORY_WT mapping\n");
651                                 md->virt_addr = (u64) ioremap(md->phys_addr, 0);
652 #endif
653                         }
654                 }
655         }
656
657         status = efi_call_phys(__va(runtime->set_virtual_address_map),
658                                ia64_boot_param->efi_memmap_size,
659                                efi_desc_size,
660                                ia64_boot_param->efi_memdesc_version,
661                                ia64_boot_param->efi_memmap);
662         if (status != EFI_SUCCESS) {
663                 printk(KERN_WARNING "warning: unable to switch EFI into "
664                        "virtual mode (status=%lu)\n", status);
665                 return;
666         }
667
668         set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
669
670         /*
671          * Now that EFI is in virtual mode, we call the EFI functions more
672          * efficiently:
673          */
674         efi.get_time = virt_get_time;
675         efi.set_time = virt_set_time;
676         efi.get_wakeup_time = virt_get_wakeup_time;
677         efi.set_wakeup_time = virt_set_wakeup_time;
678         efi.get_variable = virt_get_variable;
679         efi.get_next_variable = virt_get_next_variable;
680         efi.set_variable = virt_set_variable;
681         efi.get_next_high_mono_count = virt_get_next_high_mono_count;
682         efi.reset_system = virt_reset_system;
683 }
684
685 /*
686  * Walk the EFI memory map looking for the I/O port range.  There can only be
687  * one entry of this type, other I/O port ranges should be described via ACPI.
688  */
689 u64
690 efi_get_iobase (void)
691 {
692         void *efi_map_start, *efi_map_end, *p;
693         efi_memory_desc_t *md;
694         u64 efi_desc_size;
695
696         efi_map_start = __va(ia64_boot_param->efi_memmap);
697         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
698         efi_desc_size = ia64_boot_param->efi_memdesc_size;
699
700         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
701                 md = p;
702                 if (md->type == EFI_MEMORY_MAPPED_IO_PORT_SPACE) {
703                         if (md->attribute & EFI_MEMORY_UC)
704                                 return md->phys_addr;
705                 }
706         }
707         return 0;
708 }
709
710 static struct kern_memdesc *
711 kern_memory_descriptor (unsigned long phys_addr)
712 {
713         struct kern_memdesc *md;
714
715         for (md = kern_memmap; md->start != ~0UL; md++) {
716                 if (phys_addr - md->start < (md->num_pages << EFI_PAGE_SHIFT))
717                          return md;
718         }
719         return NULL;
720 }
721
722 static efi_memory_desc_t *
723 efi_memory_descriptor (unsigned long phys_addr)
724 {
725         void *efi_map_start, *efi_map_end, *p;
726         efi_memory_desc_t *md;
727         u64 efi_desc_size;
728
729         efi_map_start = __va(ia64_boot_param->efi_memmap);
730         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
731         efi_desc_size = ia64_boot_param->efi_memdesc_size;
732
733         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
734                 md = p;
735
736                 if (phys_addr - md->phys_addr < efi_md_size(md))
737                          return md;
738         }
739         return NULL;
740 }
741
742 static int
743 efi_memmap_intersects (unsigned long phys_addr, unsigned long size)
744 {
745         void *efi_map_start, *efi_map_end, *p;
746         efi_memory_desc_t *md;
747         u64 efi_desc_size;
748         unsigned long end;
749
750         efi_map_start = __va(ia64_boot_param->efi_memmap);
751         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
752         efi_desc_size = ia64_boot_param->efi_memdesc_size;
753
754         end = phys_addr + size;
755
756         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
757                 md = p;
758                 if (md->phys_addr < end && efi_md_end(md) > phys_addr)
759                         return 1;
760         }
761         return 0;
762 }
763
764 int
765 efi_mem_type (unsigned long phys_addr)
766 {
767         efi_memory_desc_t *md = efi_memory_descriptor(phys_addr);
768
769         if (md)
770                 return md->type;
771         return -EINVAL;
772 }
773
774 u64
775 efi_mem_attributes (unsigned long phys_addr)
776 {
777         efi_memory_desc_t *md = efi_memory_descriptor(phys_addr);
778
779         if (md)
780                 return md->attribute;
781         return 0;
782 }
783 EXPORT_SYMBOL(efi_mem_attributes);
784
785 u64
786 efi_mem_attribute (unsigned long phys_addr, unsigned long size)
787 {
788         unsigned long end = phys_addr + size;
789         efi_memory_desc_t *md = efi_memory_descriptor(phys_addr);
790         u64 attr;
791
792         if (!md)
793                 return 0;
794
795         /*
796          * EFI_MEMORY_RUNTIME is not a memory attribute; it just tells
797          * the kernel that firmware needs this region mapped.
798          */
799         attr = md->attribute & ~EFI_MEMORY_RUNTIME;
800         do {
801                 unsigned long md_end = efi_md_end(md);
802
803                 if (end <= md_end)
804                         return attr;
805
806                 md = efi_memory_descriptor(md_end);
807                 if (!md || (md->attribute & ~EFI_MEMORY_RUNTIME) != attr)
808                         return 0;
809         } while (md);
810         return 0;       /* never reached */
811 }
812
813 u64
814 kern_mem_attribute (unsigned long phys_addr, unsigned long size)
815 {
816         unsigned long end = phys_addr + size;
817         struct kern_memdesc *md;
818         u64 attr;
819
820         /*
821          * This is a hack for ioremap calls before we set up kern_memmap.
822          * Maybe we should do efi_memmap_init() earlier instead.
823          */
824         if (!kern_memmap) {
825                 attr = efi_mem_attribute(phys_addr, size);
826                 if (attr & EFI_MEMORY_WB)
827                         return EFI_MEMORY_WB;
828                 return 0;
829         }
830
831         md = kern_memory_descriptor(phys_addr);
832         if (!md)
833                 return 0;
834
835         attr = md->attribute;
836         do {
837                 unsigned long md_end = kmd_end(md);
838
839                 if (end <= md_end)
840                         return attr;
841
842                 md = kern_memory_descriptor(md_end);
843                 if (!md || md->attribute != attr)
844                         return 0;
845         } while (md);
846         return 0;       /* never reached */
847 }
848
849 int
850 valid_phys_addr_range (phys_addr_t phys_addr, unsigned long size)
851 {
852         u64 attr;
853
854         /*
855          * /dev/mem reads and writes use copy_to_user(), which implicitly
856          * uses a granule-sized kernel identity mapping.  It's really
857          * only safe to do this for regions in kern_memmap.  For more
858          * details, see Documentation/ia64/aliasing.rst.
859          */
860         attr = kern_mem_attribute(phys_addr, size);
861         if (attr & EFI_MEMORY_WB || attr & EFI_MEMORY_UC)
862                 return 1;
863         return 0;
864 }
865
866 int
867 valid_mmap_phys_addr_range (unsigned long pfn, unsigned long size)
868 {
869         unsigned long phys_addr = pfn << PAGE_SHIFT;
870         u64 attr;
871
872         attr = efi_mem_attribute(phys_addr, size);
873
874         /*
875          * /dev/mem mmap uses normal user pages, so we don't need the entire
876          * granule, but the entire region we're mapping must support the same
877          * attribute.
878          */
879         if (attr & EFI_MEMORY_WB || attr & EFI_MEMORY_UC)
880                 return 1;
881
882         /*
883          * Intel firmware doesn't tell us about all the MMIO regions, so
884          * in general we have to allow mmap requests.  But if EFI *does*
885          * tell us about anything inside this region, we should deny it.
886          * The user can always map a smaller region to avoid the overlap.
887          */
888         if (efi_memmap_intersects(phys_addr, size))
889                 return 0;
890
891         return 1;
892 }
893
894 pgprot_t
895 phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size,
896                      pgprot_t vma_prot)
897 {
898         unsigned long phys_addr = pfn << PAGE_SHIFT;
899         u64 attr;
900
901         /*
902          * For /dev/mem mmap, we use user mappings, but if the region is
903          * in kern_memmap (and hence may be covered by a kernel mapping),
904          * we must use the same attribute as the kernel mapping.
905          */
906         attr = kern_mem_attribute(phys_addr, size);
907         if (attr & EFI_MEMORY_WB)
908                 return pgprot_cacheable(vma_prot);
909         else if (attr & EFI_MEMORY_UC)
910                 return pgprot_noncached(vma_prot);
911
912         /*
913          * Some chipsets don't support UC access to memory.  If
914          * WB is supported, we prefer that.
915          */
916         if (efi_mem_attribute(phys_addr, size) & EFI_MEMORY_WB)
917                 return pgprot_cacheable(vma_prot);
918
919         return pgprot_noncached(vma_prot);
920 }
921
922 int __init
923 efi_uart_console_only(void)
924 {
925         efi_status_t status;
926         char *s, name[] = "ConOut";
927         efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
928         efi_char16_t *utf16, name_utf16[32];
929         unsigned char data[1024];
930         unsigned long size = sizeof(data);
931         struct efi_generic_dev_path *hdr, *end_addr;
932         int uart = 0;
933
934         /* Convert to UTF-16 */
935         utf16 = name_utf16;
936         s = name;
937         while (*s)
938                 *utf16++ = *s++ & 0x7f;
939         *utf16 = 0;
940
941         status = efi.get_variable(name_utf16, &guid, NULL, &size, data);
942         if (status != EFI_SUCCESS) {
943                 printk(KERN_ERR "No EFI %s variable?\n", name);
944                 return 0;
945         }
946
947         hdr = (struct efi_generic_dev_path *) data;
948         end_addr = (struct efi_generic_dev_path *) ((u8 *) data + size);
949         while (hdr < end_addr) {
950                 if (hdr->type == EFI_DEV_MSG &&
951                     hdr->sub_type == EFI_DEV_MSG_UART)
952                         uart = 1;
953                 else if (hdr->type == EFI_DEV_END_PATH ||
954                           hdr->type == EFI_DEV_END_PATH2) {
955                         if (!uart)
956                                 return 0;
957                         if (hdr->sub_type == EFI_DEV_END_ENTIRE)
958                                 return 1;
959                         uart = 0;
960                 }
961                 hdr = (struct efi_generic_dev_path *)((u8 *) hdr + hdr->length);
962         }
963         printk(KERN_ERR "Malformed %s value\n", name);
964         return 0;
965 }
966
967 /*
968  * Look for the first granule aligned memory descriptor memory
969  * that is big enough to hold EFI memory map. Make sure this
970  * descriptor is at least granule sized so it does not get trimmed
971  */
972 struct kern_memdesc *
973 find_memmap_space (void)
974 {
975         u64     contig_low=0, contig_high=0;
976         u64     as = 0, ae;
977         void *efi_map_start, *efi_map_end, *p, *q;
978         efi_memory_desc_t *md, *pmd = NULL, *check_md;
979         u64     space_needed, efi_desc_size;
980         unsigned long total_mem = 0;
981
982         efi_map_start = __va(ia64_boot_param->efi_memmap);
983         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
984         efi_desc_size = ia64_boot_param->efi_memdesc_size;
985
986         /*
987          * Worst case: we need 3 kernel descriptors for each efi descriptor
988          * (if every entry has a WB part in the middle, and UC head and tail),
989          * plus one for the end marker.
990          */
991         space_needed = sizeof(kern_memdesc_t) *
992                 (3 * (ia64_boot_param->efi_memmap_size/efi_desc_size) + 1);
993
994         for (p = efi_map_start; p < efi_map_end; pmd = md, p += efi_desc_size) {
995                 md = p;
996                 if (!efi_wb(md)) {
997                         continue;
998                 }
999                 if (pmd == NULL || !efi_wb(pmd) ||
1000                     efi_md_end(pmd) != md->phys_addr) {
1001                         contig_low = GRANULEROUNDUP(md->phys_addr);
1002                         contig_high = efi_md_end(md);
1003                         for (q = p + efi_desc_size; q < efi_map_end;
1004                              q += efi_desc_size) {
1005                                 check_md = q;
1006                                 if (!efi_wb(check_md))
1007                                         break;
1008                                 if (contig_high != check_md->phys_addr)
1009                                         break;
1010                                 contig_high = efi_md_end(check_md);
1011                         }
1012                         contig_high = GRANULEROUNDDOWN(contig_high);
1013                 }
1014                 if (!is_memory_available(md) || md->type == EFI_LOADER_DATA)
1015                         continue;
1016
1017                 /* Round ends inward to granule boundaries */
1018                 as = max(contig_low, md->phys_addr);
1019                 ae = min(contig_high, efi_md_end(md));
1020
1021                 /* keep within max_addr= and min_addr= command line arg */
1022                 as = max(as, min_addr);
1023                 ae = min(ae, max_addr);
1024                 if (ae <= as)
1025                         continue;
1026
1027                 /* avoid going over mem= command line arg */
1028                 if (total_mem + (ae - as) > mem_limit)
1029                         ae -= total_mem + (ae - as) - mem_limit;
1030
1031                 if (ae <= as)
1032                         continue;
1033
1034                 if (ae - as > space_needed)
1035                         break;
1036         }
1037         if (p >= efi_map_end)
1038                 panic("Can't allocate space for kernel memory descriptors");
1039
1040         return __va(as);
1041 }
1042
1043 /*
1044  * Walk the EFI memory map and gather all memory available for kernel
1045  * to use.  We can allocate partial granules only if the unavailable
1046  * parts exist, and are WB.
1047  */
1048 unsigned long
1049 efi_memmap_init(u64 *s, u64 *e)
1050 {
1051         struct kern_memdesc *k, *prev = NULL;
1052         u64     contig_low=0, contig_high=0;
1053         u64     as, ae, lim;
1054         void *efi_map_start, *efi_map_end, *p, *q;
1055         efi_memory_desc_t *md, *pmd = NULL, *check_md;
1056         u64     efi_desc_size;
1057         unsigned long total_mem = 0;
1058
1059         k = kern_memmap = find_memmap_space();
1060
1061         efi_map_start = __va(ia64_boot_param->efi_memmap);
1062         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
1063         efi_desc_size = ia64_boot_param->efi_memdesc_size;
1064
1065         for (p = efi_map_start; p < efi_map_end; pmd = md, p += efi_desc_size) {
1066                 md = p;
1067                 if (!efi_wb(md)) {
1068                         if (efi_uc(md) &&
1069                             (md->type == EFI_CONVENTIONAL_MEMORY ||
1070                              md->type == EFI_BOOT_SERVICES_DATA)) {
1071                                 k->attribute = EFI_MEMORY_UC;
1072                                 k->start = md->phys_addr;
1073                                 k->num_pages = md->num_pages;
1074                                 k++;
1075                         }
1076                         continue;
1077                 }
1078                 if (pmd == NULL || !efi_wb(pmd) ||
1079                     efi_md_end(pmd) != md->phys_addr) {
1080                         contig_low = GRANULEROUNDUP(md->phys_addr);
1081                         contig_high = efi_md_end(md);
1082                         for (q = p + efi_desc_size; q < efi_map_end;
1083                              q += efi_desc_size) {
1084                                 check_md = q;
1085                                 if (!efi_wb(check_md))
1086                                         break;
1087                                 if (contig_high != check_md->phys_addr)
1088                                         break;
1089                                 contig_high = efi_md_end(check_md);
1090                         }
1091                         contig_high = GRANULEROUNDDOWN(contig_high);
1092                 }
1093                 if (!is_memory_available(md))
1094                         continue;
1095
1096                 /*
1097                  * Round ends inward to granule boundaries
1098                  * Give trimmings to uncached allocator
1099                  */
1100                 if (md->phys_addr < contig_low) {
1101                         lim = min(efi_md_end(md), contig_low);
1102                         if (efi_uc(md)) {
1103                                 if (k > kern_memmap &&
1104                                     (k-1)->attribute == EFI_MEMORY_UC &&
1105                                     kmd_end(k-1) == md->phys_addr) {
1106                                         (k-1)->num_pages +=
1107                                                 (lim - md->phys_addr)
1108                                                 >> EFI_PAGE_SHIFT;
1109                                 } else {
1110                                         k->attribute = EFI_MEMORY_UC;
1111                                         k->start = md->phys_addr;
1112                                         k->num_pages = (lim - md->phys_addr)
1113                                                 >> EFI_PAGE_SHIFT;
1114                                         k++;
1115                                 }
1116                         }
1117                         as = contig_low;
1118                 } else
1119                         as = md->phys_addr;
1120
1121                 if (efi_md_end(md) > contig_high) {
1122                         lim = max(md->phys_addr, contig_high);
1123                         if (efi_uc(md)) {
1124                                 if (lim == md->phys_addr && k > kern_memmap &&
1125                                     (k-1)->attribute == EFI_MEMORY_UC &&
1126                                     kmd_end(k-1) == md->phys_addr) {
1127                                         (k-1)->num_pages += md->num_pages;
1128                                 } else {
1129                                         k->attribute = EFI_MEMORY_UC;
1130                                         k->start = lim;
1131                                         k->num_pages = (efi_md_end(md) - lim)
1132                                                 >> EFI_PAGE_SHIFT;
1133                                         k++;
1134                                 }
1135                         }
1136                         ae = contig_high;
1137                 } else
1138                         ae = efi_md_end(md);
1139
1140                 /* keep within max_addr= and min_addr= command line arg */
1141                 as = max(as, min_addr);
1142                 ae = min(ae, max_addr);
1143                 if (ae <= as)
1144                         continue;
1145
1146                 /* avoid going over mem= command line arg */
1147                 if (total_mem + (ae - as) > mem_limit)
1148                         ae -= total_mem + (ae - as) - mem_limit;
1149
1150                 if (ae <= as)
1151                         continue;
1152                 if (prev && kmd_end(prev) == md->phys_addr) {
1153                         prev->num_pages += (ae - as) >> EFI_PAGE_SHIFT;
1154                         total_mem += ae - as;
1155                         continue;
1156                 }
1157                 k->attribute = EFI_MEMORY_WB;
1158                 k->start = as;
1159                 k->num_pages = (ae - as) >> EFI_PAGE_SHIFT;
1160                 total_mem += ae - as;
1161                 prev = k++;
1162         }
1163         k->start = ~0L; /* end-marker */
1164
1165         /* reserve the memory we are using for kern_memmap */
1166         *s = (u64)kern_memmap;
1167         *e = (u64)++k;
1168
1169         return total_mem;
1170 }
1171
1172 void
1173 efi_initialize_iomem_resources(struct resource *code_resource,
1174                                struct resource *data_resource,
1175                                struct resource *bss_resource)
1176 {
1177         struct resource *res;
1178         void *efi_map_start, *efi_map_end, *p;
1179         efi_memory_desc_t *md;
1180         u64 efi_desc_size;
1181         char *name;
1182         unsigned long flags, desc;
1183
1184         efi_map_start = __va(ia64_boot_param->efi_memmap);
1185         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
1186         efi_desc_size = ia64_boot_param->efi_memdesc_size;
1187
1188         res = NULL;
1189
1190         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
1191                 md = p;
1192
1193                 if (md->num_pages == 0) /* should not happen */
1194                         continue;
1195
1196                 flags = IORESOURCE_MEM | IORESOURCE_BUSY;
1197                 desc = IORES_DESC_NONE;
1198
1199                 switch (md->type) {
1200
1201                         case EFI_MEMORY_MAPPED_IO:
1202                         case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
1203                                 continue;
1204
1205                         case EFI_LOADER_CODE:
1206                         case EFI_LOADER_DATA:
1207                         case EFI_BOOT_SERVICES_DATA:
1208                         case EFI_BOOT_SERVICES_CODE:
1209                         case EFI_CONVENTIONAL_MEMORY:
1210                                 if (md->attribute & EFI_MEMORY_WP) {
1211                                         name = "System ROM";
1212                                         flags |= IORESOURCE_READONLY;
1213                                 } else if (md->attribute == EFI_MEMORY_UC) {
1214                                         name = "Uncached RAM";
1215                                 } else {
1216                                         name = "System RAM";
1217                                         flags |= IORESOURCE_SYSRAM;
1218                                 }
1219                                 break;
1220
1221                         case EFI_ACPI_MEMORY_NVS:
1222                                 name = "ACPI Non-volatile Storage";
1223                                 desc = IORES_DESC_ACPI_NV_STORAGE;
1224                                 break;
1225
1226                         case EFI_UNUSABLE_MEMORY:
1227                                 name = "reserved";
1228                                 flags |= IORESOURCE_DISABLED;
1229                                 break;
1230
1231                         case EFI_PERSISTENT_MEMORY:
1232                                 name = "Persistent Memory";
1233                                 desc = IORES_DESC_PERSISTENT_MEMORY;
1234                                 break;
1235
1236                         case EFI_RESERVED_TYPE:
1237                         case EFI_RUNTIME_SERVICES_CODE:
1238                         case EFI_RUNTIME_SERVICES_DATA:
1239                         case EFI_ACPI_RECLAIM_MEMORY:
1240                         default:
1241                                 name = "reserved";
1242                                 break;
1243                 }
1244
1245                 if ((res = kzalloc(sizeof(struct resource),
1246                                    GFP_KERNEL)) == NULL) {
1247                         printk(KERN_ERR
1248                                "failed to allocate resource for iomem\n");
1249                         return;
1250                 }
1251
1252                 res->name = name;
1253                 res->start = md->phys_addr;
1254                 res->end = md->phys_addr + efi_md_size(md) - 1;
1255                 res->flags = flags;
1256                 res->desc = desc;
1257
1258                 if (insert_resource(&iomem_resource, res) < 0)
1259                         kfree(res);
1260                 else {
1261                         /*
1262                          * We don't know which region contains
1263                          * kernel data so we try it repeatedly and
1264                          * let the resource manager test it.
1265                          */
1266                         insert_resource(res, code_resource);
1267                         insert_resource(res, data_resource);
1268                         insert_resource(res, bss_resource);
1269 #ifdef CONFIG_KEXEC
1270                         insert_resource(res, &efi_memmap_res);
1271                         insert_resource(res, &boot_param_res);
1272                         if (crashk_res.end > crashk_res.start)
1273                                 insert_resource(res, &crashk_res);
1274 #endif
1275                 }
1276         }
1277 }
1278
1279 #ifdef CONFIG_KEXEC
1280 /* find a block of memory aligned to 64M exclude reserved regions
1281    rsvd_regions are sorted
1282  */
1283 unsigned long __init
1284 kdump_find_rsvd_region (unsigned long size, struct rsvd_region *r, int n)
1285 {
1286         int i;
1287         u64 start, end;
1288         u64 alignment = 1UL << _PAGE_SIZE_64M;
1289         void *efi_map_start, *efi_map_end, *p;
1290         efi_memory_desc_t *md;
1291         u64 efi_desc_size;
1292
1293         efi_map_start = __va(ia64_boot_param->efi_memmap);
1294         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
1295         efi_desc_size = ia64_boot_param->efi_memdesc_size;
1296
1297         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
1298                 md = p;
1299                 if (!efi_wb(md))
1300                         continue;
1301                 start = ALIGN(md->phys_addr, alignment);
1302                 end = efi_md_end(md);
1303                 for (i = 0; i < n; i++) {
1304                         if (__pa(r[i].start) >= start && __pa(r[i].end) < end) {
1305                                 if (__pa(r[i].start) > start + size)
1306                                         return start;
1307                                 start = ALIGN(__pa(r[i].end), alignment);
1308                                 if (i < n-1 &&
1309                                     __pa(r[i+1].start) < start + size)
1310                                         continue;
1311                                 else
1312                                         break;
1313                         }
1314                 }
1315                 if (end > start + size)
1316                         return start;
1317         }
1318
1319         printk(KERN_WARNING
1320                "Cannot reserve 0x%lx byte of memory for crashdump\n", size);
1321         return ~0UL;
1322 }
1323 #endif
1324
1325 #ifdef CONFIG_CRASH_DUMP
1326 /* locate the size find a the descriptor at a certain address */
1327 unsigned long __init
1328 vmcore_find_descriptor_size (unsigned long address)
1329 {
1330         void *efi_map_start, *efi_map_end, *p;
1331         efi_memory_desc_t *md;
1332         u64 efi_desc_size;
1333         unsigned long ret = 0;
1334
1335         efi_map_start = __va(ia64_boot_param->efi_memmap);
1336         efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
1337         efi_desc_size = ia64_boot_param->efi_memdesc_size;
1338
1339         for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
1340                 md = p;
1341                 if (efi_wb(md) && md->type == EFI_LOADER_DATA
1342                     && md->phys_addr == address) {
1343                         ret = efi_md_size(md);
1344                         break;
1345                 }
1346         }
1347
1348         if (ret == 0)
1349                 printk(KERN_WARNING "Cannot locate EFI vmcore descriptor\n");
1350
1351         return ret;
1352 }
1353 #endif