aboutsummaryrefslogtreecommitdiffstats
path: root/arch/ia64/kernel/efi.c
blob: 4a3b1aac43e737e4082d36eb5eee0846628fc73a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
/*
 * Extensible Firmware Interface
 *
 * Based on Extensible Firmware Interface Specification version 0.9 April 30, 1999
 *
 * Copyright (C) 1999 VA Linux Systems
 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
 * Copyright (C) 1999-2003 Hewlett-Packard Co.
 *	David Mosberger-Tang <davidm@hpl.hp.com>
 *	Stephane Eranian <eranian@hpl.hp.com>
 *
 * All EFI Runtime Services are not implemented yet as EFI only
 * supports physical mode addressing on SoftSDV. This is to be fixed
 * in a future version.  --drummond 1999-07-20
 *
 * Implemented EFI runtime services and virtual mode calls.  --davidm
 *
 * Goutham Rao: <goutham.rao@intel.com>
 *	Skip non-WB memory and ignore empty memory ranges.
 */
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/time.h>
#include <linux/efi.h>

#include <asm/io.h>
#include <asm/kregs.h>
#include <asm/meminit.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/mca.h>

#define EFI_DEBUG	0

extern efi_status_t efi_call_phys (void *, ...);

struct efi efi;
EXPORT_SYMBOL(efi);
static efi_runtime_services_t *runtime;
static unsigned long mem_limit = ~0UL, max_addr = ~0UL;

#define efi_call_virt(f, args...)	(*(f))(args)

#define STUB_GET_TIME(prefix, adjust_arg)							  \
static efi_status_t										  \
prefix##_get_time (efi_time_t *tm, efi_time_cap_t *tc)						  \
{												  \
	struct ia64_fpreg fr[6];								  \
	efi_time_cap_t *atc = NULL;								  \
	efi_status_t ret;									  \
												  \
	if (tc)											  \
		atc = adjust_arg(tc);								  \
	ia64_save_scratch_fpregs(fr);								  \
	ret = efi_call_##prefix((efi_get_time_t *) __va(runtime->get_time), adjust_arg(tm), atc); \
	ia64_load_scratch_fpregs(fr);								  \
	return ret;										  \
}

#define STUB_SET_TIME(prefix, adjust_arg)							\
static efi_status_t										\
prefix##_set_time (efi_time_t *tm)								\
{												\
	struct ia64_fpreg fr[6];								\
	efi_status_t ret;									\
												\
	ia64_save_scratch_fpregs(fr);								\
	ret = efi_call_##prefix((efi_set_time_t *) __va(runtime->set_time), adjust_arg(tm));	\
	ia64_load_scratch_fpregs(fr);								\
	return ret;										\
}

#define STUB_GET_WAKEUP_TIME(prefix, adjust_arg)						\
static efi_status_t										\
prefix##_get_wakeup_time (efi_bool_t *enabled, efi_bool_t *pending, efi_time_t *tm)		\
{												\
	struct ia64_fpreg fr[6];								\
	efi_status_t ret;									\
												\
	ia64_save_scratch_fpregs(fr);								\
	ret = efi_call_##prefix((efi_get_wakeup_time_t *) __va(runtime->get_wakeup_time),	\
				adjust_arg(enabled), adjust_arg(pending), adjust_arg(tm));	\
	ia64_load_scratch_fpregs(fr);								\
	return ret;										\
}

#define STUB_SET_WAKEUP_TIME(prefix, adjust_arg)						\
static efi_status_t										\
prefix##_set_wakeup_time (efi_bool_t enabled, efi_time_t *tm)					\
{												\
	struct ia64_fpreg fr[6];								\
	efi_time_t *atm = NULL;									\
	efi_status_t ret;									\
												\
	if (tm)											\
		atm = adjust_arg(tm);								\
	ia64_save_scratch_fpregs(fr);								\
	ret = efi_call_##prefix((efi_set_wakeup_time_t *) __va(runtime->set_wakeup_time),	\
				enabled, atm);							\
	ia64_load_scratch_fpregs(fr);								\
	return ret;										\
}

#define STUB_GET_VARIABLE(prefix, adjust_arg)						\
static efi_status_t									\
prefix##_get_variable (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,		\
		       unsigned long *data_size, void *data)				\
{											\
	struct ia64_fpreg fr[6];							\
	u32 *aattr = NULL;									\
	efi_status_t ret;								\
											\
	if (attr)									\
		aattr = adjust_arg(attr);						\
	ia64_save_scratch_fpregs(fr);							\
	ret = efi_call_##prefix((efi_get_variable_t *) __va(runtime->get_variable),	\
				adjust_arg(name), adjust_arg(vendor), aattr,		\
				adjust_arg(data_size), adjust_arg(data));		\
	ia64_load_scratch_fpregs(fr);							\
	return ret;									\
}

#define STUB_GET_NEXT_VARIABLE(prefix, adjust_arg)						\
static efi_status_t										\
prefix##_get_next_variable (unsigned long *name_size, efi_char16_t *name, efi_guid_t *vendor)	\
{												\
	struct ia64_fpreg fr[6];								\
	efi_status_t ret;									\
												\
	ia64_save_scratch_fpregs(fr);								\
	ret = efi_call_##prefix((efi_get_next_variable_t *) __va(runtime->get_next_variable),	\
				adjust_arg(name_size), adjust_arg(name), adjust_arg(vendor));	\
	ia64_load_scratch_fpregs(fr);								\
	return ret;										\
}

#define STUB_SET_VARIABLE(prefix, adjust_arg)						\
static efi_status_t									\
prefix##_set_variable (efi_char16_t *name, efi_guid_t *vendor, unsigned long attr,	\
		       unsigned long data_size, void *data)				\
{											\
	struct ia64_fpreg fr[6];							\
	efi_status_t ret;								\
											\
	ia64_save_scratch_fpregs(fr);							\
	ret = efi_call_##prefix((efi_set_variable_t *) __va(runtime->set_variable),	\
				adjust_arg(name), adjust_arg(vendor), attr, data_size,	\
				adjust_arg(data));					\
	ia64_load_scratch_fpregs(fr);							\
	return ret;									\
}

#define STUB_GET_NEXT_HIGH_MONO_COUNT(prefix, adjust_arg)					\
static efi_status_t										\
prefix##_get_next_high_mono_count (u32 *count)							\
{												\
	struct ia64_fpreg fr[6];								\
	efi_status_t ret;									\
												\
	ia64_save_scratch_fpregs(fr);								\
	ret = efi_call_##prefix((efi_get_next_high_mono_count_t *)				\
				__va(runtime->get_next_high_mono_count), adjust_arg(count));	\
	ia64_load_scratch_fpregs(fr);								\
	return ret;										\
}

#define STUB_RESET_SYSTEM(prefix, adjust_arg)					\
static void									\
prefix##_reset_system (int reset_type, efi_status_t status,			\
		       unsigned long data_size, efi_char16_t *data)		\
{										\
	struct ia64_fpreg fr[6];						\
	efi_char16_t *adata = NULL;						\
										\
	if (data)								\
		adata = adjust_arg(data);					\
										\
	ia64_save_scratch_fpregs(fr);						\
	efi_call_##prefix((efi_reset_system_t *) __va(runtime->reset_system),	\
			  reset_type, status, data_size, adata);		\
	/* should not return, but just in case... */				\
	ia64_load_scratch_fpregs(fr);						\
}

#define phys_ptr(arg)	((__typeof__(arg)) ia64_tpa(arg))

STUB_GET_TIME(phys, phys_ptr)
STUB_SET_TIME(phys, phys_ptr)
STUB_GET_WAKEUP_TIME(phys, phys_ptr)
STUB_SET_WAKEUP_TIME(phys, phys_ptr)
STUB_GET_VARIABLE(phys, phys_ptr)
STUB_GET_NEXT_VARIABLE(phys, phys_ptr)
STUB_SET_VARIABLE(phys, phys_ptr)
STUB_GET_NEXT_HIGH_MONO_COUNT(phys, phys_ptr)
STUB_RESET_SYSTEM(phys, phys_ptr)

#define id(arg)	arg

STUB_GET_TIME(virt, id)
STUB_SET_TIME(virt, id)
STUB_GET_WAKEUP_TIME(virt, id)
STUB_SET_WAKEUP_TIME(virt, id)
STUB_GET_VARIABLE(virt, id)
STUB_GET_NEXT_VARIABLE(virt, id)
STUB_SET_VARIABLE(virt, id)
STUB_GET_NEXT_HIGH_MONO_COUNT(virt, id)
STUB_RESET_SYSTEM(virt, id)

void
efi_gettimeofday (struct timespec *ts)
{
	efi_time_t tm;

	memset(ts, 0, sizeof(ts));
	if ((*efi.get_time)(&tm, NULL) != EFI_SUCCESS)
		return;

	ts->tv_sec = mktime(tm.year, tm.month, tm.day, tm.hour, tm.minute, tm.second);
	ts->tv_nsec = tm.nanosecond;
}

static int
is_available_memory (efi_memory_desc_t *md)
{
	if (!(md->attribute & EFI_MEMORY_WB))
		return 0;

	switch (md->type) {
	      case EFI_LOADER_CODE:
	      case EFI_LOADER_DATA:
	      case EFI_BOOT_SERVICES_CODE:
	      case EFI_BOOT_SERVICES_DATA:
	      case EFI_CONVENTIONAL_MEMORY:
		return 1;
	}
	return 0;
}

/*
 * Trim descriptor MD so its starts at address START_ADDR.  If the descriptor covers
 * memory that is normally available to the kernel, issue a warning that some memory
 * is being ignored.
 */
static void
trim_bottom (efi_memory_desc_t *md, u64 start_addr)
{
	u64 num_skipped_pages;

	if (md->phys_addr >= start_addr || !md->num_pages)
		return;

	num_skipped_pages = (start_addr - md->phys_addr) >> EFI_PAGE_SHIFT;
	if (num_skipped_pages > md->num_pages)
		num_skipped_pages = md->num_pages;

	if (is_available_memory(md))
		printk(KERN_NOTICE "efi.%s: ignoring %luKB of memory at 0x%lx due to granule hole "
		       "at 0x%lx\n", __FUNCTION__,
		       (num_skipped_pages << EFI_PAGE_SHIFT) >> 10,
		       md->phys_addr, start_addr - IA64_GRANULE_SIZE);
	/*
	 * NOTE: Don't set md->phys_addr to START_ADDR because that could cause the memory
	 * descriptor list to become unsorted.  In such a case, md->num_pages will be
	 * zero, so the Right Thing will happen.
	 */
	md->phys_addr += num_skipped_pages << EFI_PAGE_SHIFT;
	md->num_pages -= num_skipped_pages;
}

static void
trim_top (efi_memory_desc_t *md, u64 end_addr)
{
	u64 num_dropped_pages, md_end_addr;

	md_end_addr = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);

	if (md_end_addr <= end_addr || !md->num_pages)
		return;

	num_dropped_pages = (md_end_addr - end_addr) >> EFI_PAGE_SHIFT;
	if (num_dropped_pages > md->num_pages)
		num_dropped_pages = md->num_pages;

	if (is_available_memory(md))
		printk(KERN_NOTICE "efi.%s: ignoring %luKB of memory at 0x%lx due to granule hole "
		       "at 0x%lx\n", __FUNCTION__,
		       (num_dropped_pages << EFI_PAGE_SHIFT) >> 10,
		       md->phys_addr, end_addr);
	md->num_pages -= num_dropped_pages;
}

/*
 * Walks the EFI memory map and calls CALLBACK once for each EFI memory descriptor that
 * has memory that is available for OS use.
 */
void
efi_memmap_walk (efi_freemem_callback_t callback, void *arg)
{
	int prev_valid = 0;
	struct range {
		u64 start;
		u64 end;
	} prev, curr;
	void *efi_map_start, *efi_map_end, *p, *q;
	efi_memory_desc_t *md, *check_md;
	u64 efi_desc_size, start, end, granule_addr, last_granule_addr, first_non_wb_addr = 0;
	unsigned long total_mem = 0;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;

		/* skip over non-WB memory descriptors; that's all we're interested in... */
		if (!(md->attribute & EFI_MEMORY_WB))
			continue;

		/*
		 * granule_addr is the base of md's first granule.
		 * [granule_addr - first_non_wb_addr) is guaranteed to
		 * be contiguous WB memory.
		 */
		granule_addr = GRANULEROUNDDOWN(md->phys_addr);
		first_non_wb_addr = max(first_non_wb_addr, granule_addr);

		if (first_non_wb_addr < md->phys_addr) {
			trim_bottom(md, granule_addr + IA64_GRANULE_SIZE);
			granule_addr = GRANULEROUNDDOWN(md->phys_addr);
			first_non_wb_addr = max(first_non_wb_addr, granule_addr);
		}

		for (q = p; q < efi_map_end; q += efi_desc_size) {
			check_md = q;

			if ((check_md->attribute & EFI_MEMORY_WB) &&
			    (check_md->phys_addr == first_non_wb_addr))
				first_non_wb_addr += check_md->num_pages << EFI_PAGE_SHIFT;
			else
				break;		/* non-WB or hole */
		}

		last_granule_addr = GRANULEROUNDDOWN(first_non_wb_addr);
		if (last_granule_addr < md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT))
			trim_top(md, last_granule_addr);

		if (is_available_memory(md)) {
			if (md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) >= max_addr) {
				if (md->phys_addr >= max_addr)
					continue;
				md->num_pages = (max_addr - md->phys_addr) >> EFI_PAGE_SHIFT;
				first_non_wb_addr = max_addr;
			}

			if (total_mem >= mem_limit)
				continue;

			if (total_mem + (md->num_pages << EFI_PAGE_SHIFT) > mem_limit) {
				unsigned long limit_addr = md->phys_addr;

				limit_addr += mem_limit - total_mem;
				limit_addr = GRANULEROUNDDOWN(limit_addr);

				if (md->phys_addr > limit_addr)
					continue;

				md->num_pages = (limit_addr - md->phys_addr) >>
				                EFI_PAGE_SHIFT;
				first_non_wb_addr = max_addr = md->phys_addr +
				              (md->num_pages << EFI_PAGE_SHIFT);
			}
			total_mem += (md->num_pages << EFI_PAGE_SHIFT);

			if (md->num_pages == 0)
				continue;

			curr.start = PAGE_OFFSET + md->phys_addr;
			curr.end   = curr.start + (md->num_pages << EFI_PAGE_SHIFT);

			if (!prev_valid) {
				prev = curr;
				prev_valid = 1;
			} else {
				if (curr.start < prev.start)
					printk(KERN_ERR "Oops: EFI memory table not ordered!\n");

				if (prev.end == curr.start) {
					/* merge two consecutive memory ranges */
					prev.end = curr.end;
				} else {
					start = PAGE_ALIGN(prev.start);
					end = prev.end & PAGE_MASK;
					if ((end > start) && (*callback)(start, end, arg) < 0)
						return;
					prev = curr;
				}
			}
		}
	}
	if (prev_valid) {
		start = PAGE_ALIGN(prev.start);
		end = prev.end & PAGE_MASK;
		if (end > start)
			(*callback)(start, end, arg);
	}
}

/*
 * Look for the PAL_CODE region reported by EFI and maps it using an
 * ITR to enable safe PAL calls in virtual mode.  See IA-64 Processor
 * Abstraction Layer chapter 11 in ADAG
 */

void *
efi_get_pal_addr (void)
{
	void *efi_map_start, *efi_map_end, *p;
	efi_memory_desc_t *md;
	u64 efi_desc_size;
	int pal_code_count = 0;
	u64 vaddr, mask;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;
		if (md->type != EFI_PAL_CODE)
			continue;

		if (++pal_code_count > 1) {
			printk(KERN_ERR "Too many EFI Pal Code memory ranges, dropped @ %lx\n",
			       md->phys_addr);
			continue;
		}
		/*
		 * The only ITLB entry in region 7 that is used is the one installed by
		 * __start().  That entry covers a 64MB range.
		 */
		mask  = ~((1 << KERNEL_TR_PAGE_SHIFT) - 1);
		vaddr = PAGE_OFFSET + md->phys_addr;

		/*
		 * We must check that the PAL mapping won't overlap with the kernel
		 * mapping.
		 *
		 * PAL code is guaranteed to be aligned on a power of 2 between 4k and
		 * 256KB and that only one ITR is needed to map it. This implies that the
		 * PAL code is always aligned on its size, i.e., the closest matching page
		 * size supported by the TLB. Therefore PAL code is guaranteed never to
		 * cross a 64MB unless it is bigger than 64MB (very unlikely!).  So for
		 * now the following test is enough to determine whether or not we need a
		 * dedicated ITR for the PAL code.
		 */
		if ((vaddr & mask) == (KERNEL_START & mask)) {
			printk(KERN_INFO "%s: no need to install ITR for PAL code\n",
			       __FUNCTION__);
			continue;
		}

		if (md->num_pages << EFI_PAGE_SHIFT > IA64_GRANULE_SIZE)
			panic("Woah!  PAL code size bigger than a granule!");

#if EFI_DEBUG
		mask  = ~((1 << IA64_GRANULE_SHIFT) - 1);

		printk(KERN_INFO "CPU %d: mapping PAL code [0x%lx-0x%lx) into [0x%lx-0x%lx)\n",
			smp_processor_id(), md->phys_addr,
			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
			vaddr & mask, (vaddr & mask) + IA64_GRANULE_SIZE);
#endif
		return __va(md->phys_addr);
	}
	printk(KERN_WARNING "%s: no PAL-code memory-descriptor found",
	       __FUNCTION__);
	return NULL;
}

void
efi_map_pal_code (void)
{
	void *pal_vaddr = efi_get_pal_addr ();
	u64 psr;

	if (!pal_vaddr)
		return;

	/*
	 * Cannot write to CRx with PSR.ic=1
	 */
	psr = ia64_clear_ic();
	ia64_itr(0x1, IA64_TR_PALCODE, GRANULEROUNDDOWN((unsigned long) pal_vaddr),
		 pte_val(pfn_pte(__pa(pal_vaddr) >> PAGE_SHIFT, PAGE_KERNEL)),
		 IA64_GRANULE_SHIFT);
	ia64_set_psr(psr);		/* restore psr */
	ia64_srlz_i();
}

void __init
efi_init (void)
{
	void *efi_map_start, *efi_map_end;
	efi_config_table_t *config_tables;
	efi_char16_t *c16;
	u64 efi_desc_size;
	char *cp, *end, vendor[100] = "unknown";
	extern char saved_command_line[];
	int i;

	/* it's too early to be able to use the standard kernel command line support... */
	for (cp = saved_command_line; *cp; ) {
		if (memcmp(cp, "mem=", 4) == 0) {
			cp += 4;
			mem_limit = memparse(cp, &end);
			if (end != cp)
				break;
			cp = end;
		} else if (memcmp(cp, "max_addr=", 9) == 0) {
			cp += 9;
			max_addr = GRANULEROUNDDOWN(memparse(cp, &end));
			if (end != cp)
				break;
			cp = end;
		} else {
			while (*cp != ' ' && *cp)
				++cp;
			while (*cp == ' ')
				++cp;
		}
	}
	if (max_addr != ~0UL)
		printk(KERN_INFO "Ignoring memory above %luMB\n", max_addr >> 20);

	efi.systab = __va(ia64_boot_param->efi_systab);

	/*
	 * Verify the EFI Table
	 */
	if (efi.systab == NULL)
		panic("Woah! Can't find EFI system table.\n");
	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
		panic("Woah! EFI system table signature incorrect\n");
	if ((efi.systab->hdr.revision ^ EFI_SYSTEM_TABLE_REVISION) >> 16 != 0)
		printk(KERN_WARNING "Warning: EFI system table major version mismatch: "
		       "got %d.%02d, expected %d.%02d\n",
		       efi.systab->hdr.revision >> 16, efi.systab->hdr.revision & 0xffff,
		       EFI_SYSTEM_TABLE_REVISION >> 16, EFI_SYSTEM_TABLE_REVISION & 0xffff);

	config_tables = __va(efi.systab->tables);

	/* Show what we know for posterity */
	c16 = __va(efi.systab->fw_vendor);
	if (c16) {
		for (i = 0;i < (int) sizeof(vendor) && *c16; ++i)
			vendor[i] = *c16++;
		vendor[i] = '\0';
	}

	printk(KERN_INFO "EFI v%u.%.02u by %s:",
	       efi.systab->hdr.revision >> 16, efi.systab->hdr.revision & 0xffff, vendor);

	for (i = 0; i < (int) efi.systab->nr_tables; i++) {
		if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
			efi.mps = __va(config_tables[i].table);
			printk(" MPS=0x%lx", config_tables[i].table);
		} else if (efi_guidcmp(config_tables[i].guid, ACPI_20_TABLE_GUID) == 0) {
			efi.acpi20 = __va(config_tables[i].table);
			printk(" ACPI 2.0=0x%lx", config_tables[i].table);
		} else if (efi_guidcmp(config_tables[i].guid, ACPI_TABLE_GUID) == 0) {
			efi.acpi = __va(config_tables[i].table);
			printk(" ACPI=0x%lx", config_tables[i].table);
		} else if (efi_guidcmp(config_tables[i].guid, SMBIOS_TABLE_GUID) == 0) {
			efi.smbios = __va(config_tables[i].table);
			printk(" SMBIOS=0x%lx", config_tables[i].table);
		} else if (efi_guidcmp(config_tables[i].guid, SAL_SYSTEM_TABLE_GUID) == 0) {
			efi.sal_systab = __va(config_tables[i].table);
			printk(" SALsystab=0x%lx", config_tables[i].table);
		} else if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
			efi.hcdp = __va(config_tables[i].table);
			printk(" HCDP=0x%lx", config_tables[i].table);
		}
	}
	printk("\n");

	runtime = __va(efi.systab->runtime);
	efi.get_time = phys_get_time;
	efi.set_time = phys_set_time;
	efi.get_wakeup_time = phys_get_wakeup_time;
	efi.set_wakeup_time = phys_set_wakeup_time;
	efi.get_variable = phys_get_variable;
	efi.get_next_variable = phys_get_next_variable;
	efi.set_variable = phys_set_variable;
	efi.get_next_high_mono_count = phys_get_next_high_mono_count;
	efi.reset_system = phys_reset_system;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

#if EFI_DEBUG
	/* print EFI memory map: */
	{
		efi_memory_desc_t *md;
		void *p;

		for (i = 0, p = efi_map_start; p < efi_map_end; ++i, p += efi_desc_size) {
			md = p;
			printk("mem%02u: type=%u, attr=0x%lx, range=[0x%016lx-0x%016lx) (%luMB)\n",
			       i, md->type, md->attribute, md->phys_addr,
			       md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
			       md->num_pages >> (20 - EFI_PAGE_SHIFT));
		}
	}
#endif

	efi_map_pal_code();
	efi_enter_virtual_mode();
}

void
efi_enter_virtual_mode (void)
{
	void *efi_map_start, *efi_map_end, *p;
	efi_memory_desc_t *md;
	efi_status_t status;
	u64 efi_desc_size;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;
		if (md->attribute & EFI_MEMORY_RUNTIME) {
			/*
			 * Some descriptors have multiple bits set, so the order of
			 * the tests is relevant.
			 */
			if (md->attribute & EFI_MEMORY_WB) {
				md->virt_addr = (u64) __va(md->phys_addr);
			} else if (md->attribute & EFI_MEMORY_UC) {
				md->virt_addr = (u64) ioremap(md->phys_addr, 0);
			} else if (md->attribute & EFI_MEMORY_WC) {
#if 0
				md->virt_addr = ia64_remap(md->phys_addr, (_PAGE_A | _PAGE_P
									   | _PAGE_D
									   | _PAGE_MA_WC
									   | _PAGE_PL_0
									   | _PAGE_AR_RW));
#else
				printk(KERN_INFO "EFI_MEMORY_WC mapping\n");
				md->virt_addr = (u64) ioremap(md->phys_addr, 0);
#endif
			} else if (md->attribute & EFI_MEMORY_WT) {
#if 0
				md->virt_addr = ia64_remap(md->phys_addr, (_PAGE_A | _PAGE_P
									   | _PAGE_D | _PAGE_MA_WT
									   | _PAGE_PL_0
									   | _PAGE_AR_RW));
#else
				printk(KERN_INFO "EFI_MEMORY_WT mapping\n");
				md->virt_addr = (u64) ioremap(md->phys_addr, 0);
#endif
			}
		}
	}

	status = efi_call_phys(__va(runtime->set_virtual_address_map),
			       ia64_boot_param->efi_memmap_size,
			       efi_desc_size, ia64_boot_param->efi_memdesc_version,
			       ia64_boot_param->efi_memmap);
	if (status != EFI_SUCCESS) {
		printk(KERN_WARNING "warning: unable to switch EFI into virtual mode "
		       "(status=%lu)\n", status);
		return;
	}

	/*
	 * Now that EFI is in virtual mode, we call the EFI functions more efficiently:
	 */
	efi.get_time = virt_get_time;
	efi.set_time = virt_set_time;
	efi.get_wakeup_time = virt_get_wakeup_time;
	efi.set_wakeup_time = virt_set_wakeup_time;
	efi.get_variable = virt_get_variable;
	efi.get_next_variable = virt_get_next_variable;
	efi.set_variable = virt_set_variable;
	efi.get_next_high_mono_count = virt_get_next_high_mono_count;
	efi.reset_system = virt_reset_system;
}

/*
 * Walk the EFI memory map looking for the I/O port range.  There can only be one entry of
 * this type, other I/O port ranges should be described via ACPI.
 */
u64
efi_get_iobase (void)
{
	void *efi_map_start, *efi_map_end, *p;
	efi_memory_desc_t *md;
	u64 efi_desc_size;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;
		if (md->type == EFI_MEMORY_MAPPED_IO_PORT_SPACE) {
			if (md->attribute & EFI_MEMORY_UC)
				return md->phys_addr;
		}
	}
	return 0;
}

u32
efi_mem_type (unsigned long phys_addr)
{
	void *efi_map_start, *efi_map_end, *p;
	efi_memory_desc_t *md;
	u64 efi_desc_size;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;

		if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT))
			 return md->type;
	}
	return 0;
}

u64
efi_mem_attributes (unsigned long phys_addr)
{
	void *efi_map_start, *efi_map_end, *p;
	efi_memory_desc_t *md;
	u64 efi_desc_size;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;

		if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT))
			return md->attribute;
	}
	return 0;
}
EXPORT_SYMBOL(efi_mem_attributes);

int
valid_phys_addr_range (unsigned long phys_addr, unsigned long *size)
{
	void *efi_map_start, *efi_map_end, *p;
	efi_memory_desc_t *md;
	u64 efi_desc_size;

	efi_map_start = __va(ia64_boot_param->efi_memmap);
	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
	efi_desc_size = ia64_boot_param->efi_memdesc_size;

	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
		md = p;

		if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT)) {
			if (!(md->attribute & EFI_MEMORY_WB))
				return 0;

			if (*size > md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - phys_addr)
				*size = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - phys_addr;
			return 1;
		}
	}
	return 0;
}

int __init
efi_uart_console_only(void)
{
	efi_status_t status;
	char *s, name[] = "ConOut";
	efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
	efi_char16_t *utf16, name_utf16[32];
	unsigned char data[1024];
	unsigned long size = sizeof(data);
	struct efi_generic_dev_path *hdr, *end_addr;
	int uart = 0;

	/* Convert to UTF-16 */
	utf16 = name_utf16;
	s = name;
	while (*s)
		*utf16++ = *s++ & 0x7f;
	*utf16 = 0;

	status = efi.get_variable(name_utf16, &guid, NULL, &size, data);
	if (status != EFI_SUCCESS) {
		printk(KERN_ERR "No EFI %s variable?\n", name);
		return 0;
	}

	hdr = (struct efi_generic_dev_path *) data;
	end_addr = (struct efi_generic_dev_path *) ((u8 *) data + size);
	while (hdr < end_addr) {
		if (hdr->type == EFI_DEV_MSG &&
		    hdr->sub_type == EFI_DEV_MSG_UART)
			uart = 1;
		else if (hdr->type == EFI_DEV_END_PATH ||
			  hdr->type == EFI_DEV_END_PATH2) {
			if (!uart)
				return 0;
			if (hdr->sub_type == EFI_DEV_END_ENTIRE)
				return 1;
			uart = 0;
		}
		hdr = (struct efi_generic_dev_path *) ((u8 *) hdr + hdr->length);
	}
	printk(KERN_ERR "Malformed %s value\n", name);
	return 0;
}