xref: /openbmc/linux/arch/ia64/kernel/efi.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
1 /*
2  * Extensible Firmware Interface
3  *
4  * Based on Extensible Firmware Interface Specification version 0.9 April 30, 1999
5  *
6  * Copyright (C) 1999 VA Linux Systems
7  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
8  * Copyright (C) 1999-2003 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 #include <linux/config.h>
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/init.h>
25 #include <linux/types.h>
26 #include <linux/time.h>
27 #include <linux/efi.h>
28 
29 #include <asm/io.h>
30 #include <asm/kregs.h>
31 #include <asm/meminit.h>
32 #include <asm/pgtable.h>
33 #include <asm/processor.h>
34 #include <asm/mca.h>
35 
36 #define EFI_DEBUG	0
37 
38 extern efi_status_t efi_call_phys (void *, ...);
39 
40 struct efi efi;
41 EXPORT_SYMBOL(efi);
42 static efi_runtime_services_t *runtime;
43 static unsigned long mem_limit = ~0UL, max_addr = ~0UL;
44 
45 #define efi_call_virt(f, args...)	(*(f))(args)
46 
47 #define STUB_GET_TIME(prefix, adjust_arg)							  \
48 static efi_status_t										  \
49 prefix##_get_time (efi_time_t *tm, efi_time_cap_t *tc)						  \
50 {												  \
51 	struct ia64_fpreg fr[6];								  \
52 	efi_time_cap_t *atc = NULL;								  \
53 	efi_status_t ret;									  \
54 												  \
55 	if (tc)											  \
56 		atc = adjust_arg(tc);								  \
57 	ia64_save_scratch_fpregs(fr);								  \
58 	ret = efi_call_##prefix((efi_get_time_t *) __va(runtime->get_time), adjust_arg(tm), atc); \
59 	ia64_load_scratch_fpregs(fr);								  \
60 	return ret;										  \
61 }
62 
63 #define STUB_SET_TIME(prefix, adjust_arg)							\
64 static efi_status_t										\
65 prefix##_set_time (efi_time_t *tm)								\
66 {												\
67 	struct ia64_fpreg fr[6];								\
68 	efi_status_t ret;									\
69 												\
70 	ia64_save_scratch_fpregs(fr);								\
71 	ret = efi_call_##prefix((efi_set_time_t *) __va(runtime->set_time), adjust_arg(tm));	\
72 	ia64_load_scratch_fpregs(fr);								\
73 	return ret;										\
74 }
75 
76 #define STUB_GET_WAKEUP_TIME(prefix, adjust_arg)						\
77 static efi_status_t										\
78 prefix##_get_wakeup_time (efi_bool_t *enabled, efi_bool_t *pending, efi_time_t *tm)		\
79 {												\
80 	struct ia64_fpreg fr[6];								\
81 	efi_status_t ret;									\
82 												\
83 	ia64_save_scratch_fpregs(fr);								\
84 	ret = efi_call_##prefix((efi_get_wakeup_time_t *) __va(runtime->get_wakeup_time),	\
85 				adjust_arg(enabled), adjust_arg(pending), adjust_arg(tm));	\
86 	ia64_load_scratch_fpregs(fr);								\
87 	return ret;										\
88 }
89 
90 #define STUB_SET_WAKEUP_TIME(prefix, adjust_arg)						\
91 static efi_status_t										\
92 prefix##_set_wakeup_time (efi_bool_t enabled, efi_time_t *tm)					\
93 {												\
94 	struct ia64_fpreg fr[6];								\
95 	efi_time_t *atm = NULL;									\
96 	efi_status_t ret;									\
97 												\
98 	if (tm)											\
99 		atm = adjust_arg(tm);								\
100 	ia64_save_scratch_fpregs(fr);								\
101 	ret = efi_call_##prefix((efi_set_wakeup_time_t *) __va(runtime->set_wakeup_time),	\
102 				enabled, atm);							\
103 	ia64_load_scratch_fpregs(fr);								\
104 	return ret;										\
105 }
106 
107 #define STUB_GET_VARIABLE(prefix, adjust_arg)						\
108 static efi_status_t									\
109 prefix##_get_variable (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,		\
110 		       unsigned long *data_size, void *data)				\
111 {											\
112 	struct ia64_fpreg fr[6];							\
113 	u32 *aattr = NULL;									\
114 	efi_status_t ret;								\
115 											\
116 	if (attr)									\
117 		aattr = adjust_arg(attr);						\
118 	ia64_save_scratch_fpregs(fr);							\
119 	ret = efi_call_##prefix((efi_get_variable_t *) __va(runtime->get_variable),	\
120 				adjust_arg(name), adjust_arg(vendor), aattr,		\
121 				adjust_arg(data_size), adjust_arg(data));		\
122 	ia64_load_scratch_fpregs(fr);							\
123 	return ret;									\
124 }
125 
126 #define STUB_GET_NEXT_VARIABLE(prefix, adjust_arg)						\
127 static efi_status_t										\
128 prefix##_get_next_variable (unsigned long *name_size, efi_char16_t *name, efi_guid_t *vendor)	\
129 {												\
130 	struct ia64_fpreg fr[6];								\
131 	efi_status_t ret;									\
132 												\
133 	ia64_save_scratch_fpregs(fr);								\
134 	ret = efi_call_##prefix((efi_get_next_variable_t *) __va(runtime->get_next_variable),	\
135 				adjust_arg(name_size), adjust_arg(name), adjust_arg(vendor));	\
136 	ia64_load_scratch_fpregs(fr);								\
137 	return ret;										\
138 }
139 
140 #define STUB_SET_VARIABLE(prefix, adjust_arg)						\
141 static efi_status_t									\
142 prefix##_set_variable (efi_char16_t *name, efi_guid_t *vendor, unsigned long attr,	\
143 		       unsigned long data_size, void *data)				\
144 {											\
145 	struct ia64_fpreg fr[6];							\
146 	efi_status_t ret;								\
147 											\
148 	ia64_save_scratch_fpregs(fr);							\
149 	ret = efi_call_##prefix((efi_set_variable_t *) __va(runtime->set_variable),	\
150 				adjust_arg(name), adjust_arg(vendor), attr, data_size,	\
151 				adjust_arg(data));					\
152 	ia64_load_scratch_fpregs(fr);							\
153 	return ret;									\
154 }
155 
156 #define STUB_GET_NEXT_HIGH_MONO_COUNT(prefix, adjust_arg)					\
157 static efi_status_t										\
158 prefix##_get_next_high_mono_count (u32 *count)							\
159 {												\
160 	struct ia64_fpreg fr[6];								\
161 	efi_status_t ret;									\
162 												\
163 	ia64_save_scratch_fpregs(fr);								\
164 	ret = efi_call_##prefix((efi_get_next_high_mono_count_t *)				\
165 				__va(runtime->get_next_high_mono_count), adjust_arg(count));	\
166 	ia64_load_scratch_fpregs(fr);								\
167 	return ret;										\
168 }
169 
170 #define STUB_RESET_SYSTEM(prefix, adjust_arg)					\
171 static void									\
172 prefix##_reset_system (int reset_type, efi_status_t status,			\
173 		       unsigned long data_size, efi_char16_t *data)		\
174 {										\
175 	struct ia64_fpreg fr[6];						\
176 	efi_char16_t *adata = NULL;						\
177 										\
178 	if (data)								\
179 		adata = adjust_arg(data);					\
180 										\
181 	ia64_save_scratch_fpregs(fr);						\
182 	efi_call_##prefix((efi_reset_system_t *) __va(runtime->reset_system),	\
183 			  reset_type, status, data_size, adata);		\
184 	/* should not return, but just in case... */				\
185 	ia64_load_scratch_fpregs(fr);						\
186 }
187 
188 #define phys_ptr(arg)	((__typeof__(arg)) ia64_tpa(arg))
189 
190 STUB_GET_TIME(phys, phys_ptr)
191 STUB_SET_TIME(phys, phys_ptr)
192 STUB_GET_WAKEUP_TIME(phys, phys_ptr)
193 STUB_SET_WAKEUP_TIME(phys, phys_ptr)
194 STUB_GET_VARIABLE(phys, phys_ptr)
195 STUB_GET_NEXT_VARIABLE(phys, phys_ptr)
196 STUB_SET_VARIABLE(phys, phys_ptr)
197 STUB_GET_NEXT_HIGH_MONO_COUNT(phys, phys_ptr)
198 STUB_RESET_SYSTEM(phys, phys_ptr)
199 
200 #define id(arg)	arg
201 
202 STUB_GET_TIME(virt, id)
203 STUB_SET_TIME(virt, id)
204 STUB_GET_WAKEUP_TIME(virt, id)
205 STUB_SET_WAKEUP_TIME(virt, id)
206 STUB_GET_VARIABLE(virt, id)
207 STUB_GET_NEXT_VARIABLE(virt, id)
208 STUB_SET_VARIABLE(virt, id)
209 STUB_GET_NEXT_HIGH_MONO_COUNT(virt, id)
210 STUB_RESET_SYSTEM(virt, id)
211 
212 void
213 efi_gettimeofday (struct timespec *ts)
214 {
215 	efi_time_t tm;
216 
217 	memset(ts, 0, sizeof(ts));
218 	if ((*efi.get_time)(&tm, NULL) != EFI_SUCCESS)
219 		return;
220 
221 	ts->tv_sec = mktime(tm.year, tm.month, tm.day, tm.hour, tm.minute, tm.second);
222 	ts->tv_nsec = tm.nanosecond;
223 }
224 
225 static int
226 is_available_memory (efi_memory_desc_t *md)
227 {
228 	if (!(md->attribute & EFI_MEMORY_WB))
229 		return 0;
230 
231 	switch (md->type) {
232 	      case EFI_LOADER_CODE:
233 	      case EFI_LOADER_DATA:
234 	      case EFI_BOOT_SERVICES_CODE:
235 	      case EFI_BOOT_SERVICES_DATA:
236 	      case EFI_CONVENTIONAL_MEMORY:
237 		return 1;
238 	}
239 	return 0;
240 }
241 
242 typedef struct kern_memdesc {
243 	u64 attribute;
244 	u64 start;
245 	u64 num_pages;
246 } kern_memdesc_t;
247 
248 static kern_memdesc_t *kern_memmap;
249 
250 static void
251 walk (efi_freemem_callback_t callback, void *arg, u64 attr)
252 {
253 	kern_memdesc_t *k;
254 	u64 start, end, voff;
255 
256 	voff = (attr == EFI_MEMORY_WB) ? PAGE_OFFSET : __IA64_UNCACHED_OFFSET;
257 	for (k = kern_memmap; k->start != ~0UL; k++) {
258 		if (k->attribute != attr)
259 			continue;
260 		start = PAGE_ALIGN(k->start);
261 		end = (k->start + (k->num_pages << EFI_PAGE_SHIFT)) & PAGE_MASK;
262 		if (start < end)
263 			if ((*callback)(start + voff, end + voff, arg) < 0)
264 				return;
265 	}
266 }
267 
268 /*
269  * Walks the EFI memory map and calls CALLBACK once for each EFI memory descriptor that
270  * has memory that is available for OS use.
271  */
272 void
273 efi_memmap_walk (efi_freemem_callback_t callback, void *arg)
274 {
275 	walk(callback, arg, EFI_MEMORY_WB);
276 }
277 
278 /*
279  * Walks the EFI memory map and calls CALLBACK once for each EFI memory descriptor that
280  * has memory that is available for uncached allocator.
281  */
282 void
283 efi_memmap_walk_uc (efi_freemem_callback_t callback, void *arg)
284 {
285 	walk(callback, arg, EFI_MEMORY_UC);
286 }
287 
288 /*
289  * Look for the PAL_CODE region reported by EFI and maps it using an
290  * ITR to enable safe PAL calls in virtual mode.  See IA-64 Processor
291  * Abstraction Layer chapter 11 in ADAG
292  */
293 
294 void *
295 efi_get_pal_addr (void)
296 {
297 	void *efi_map_start, *efi_map_end, *p;
298 	efi_memory_desc_t *md;
299 	u64 efi_desc_size;
300 	int pal_code_count = 0;
301 	u64 vaddr, mask;
302 
303 	efi_map_start = __va(ia64_boot_param->efi_memmap);
304 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
305 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
306 
307 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
308 		md = p;
309 		if (md->type != EFI_PAL_CODE)
310 			continue;
311 
312 		if (++pal_code_count > 1) {
313 			printk(KERN_ERR "Too many EFI Pal Code memory ranges, dropped @ %lx\n",
314 			       md->phys_addr);
315 			continue;
316 		}
317 		/*
318 		 * The only ITLB entry in region 7 that is used is the one installed by
319 		 * __start().  That entry covers a 64MB range.
320 		 */
321 		mask  = ~((1 << KERNEL_TR_PAGE_SHIFT) - 1);
322 		vaddr = PAGE_OFFSET + md->phys_addr;
323 
324 		/*
325 		 * We must check that the PAL mapping won't overlap with the kernel
326 		 * mapping.
327 		 *
328 		 * PAL code is guaranteed to be aligned on a power of 2 between 4k and
329 		 * 256KB and that only one ITR is needed to map it. This implies that the
330 		 * PAL code is always aligned on its size, i.e., the closest matching page
331 		 * size supported by the TLB. Therefore PAL code is guaranteed never to
332 		 * cross a 64MB unless it is bigger than 64MB (very unlikely!).  So for
333 		 * now the following test is enough to determine whether or not we need a
334 		 * dedicated ITR for the PAL code.
335 		 */
336 		if ((vaddr & mask) == (KERNEL_START & mask)) {
337 			printk(KERN_INFO "%s: no need to install ITR for PAL code\n",
338 			       __FUNCTION__);
339 			continue;
340 		}
341 
342 		if (md->num_pages << EFI_PAGE_SHIFT > IA64_GRANULE_SIZE)
343 			panic("Woah!  PAL code size bigger than a granule!");
344 
345 #if EFI_DEBUG
346 		mask  = ~((1 << IA64_GRANULE_SHIFT) - 1);
347 
348 		printk(KERN_INFO "CPU %d: mapping PAL code [0x%lx-0x%lx) into [0x%lx-0x%lx)\n",
349 			smp_processor_id(), md->phys_addr,
350 			md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
351 			vaddr & mask, (vaddr & mask) + IA64_GRANULE_SIZE);
352 #endif
353 		return __va(md->phys_addr);
354 	}
355 	printk(KERN_WARNING "%s: no PAL-code memory-descriptor found",
356 	       __FUNCTION__);
357 	return NULL;
358 }
359 
360 void
361 efi_map_pal_code (void)
362 {
363 	void *pal_vaddr = efi_get_pal_addr ();
364 	u64 psr;
365 
366 	if (!pal_vaddr)
367 		return;
368 
369 	/*
370 	 * Cannot write to CRx with PSR.ic=1
371 	 */
372 	psr = ia64_clear_ic();
373 	ia64_itr(0x1, IA64_TR_PALCODE, GRANULEROUNDDOWN((unsigned long) pal_vaddr),
374 		 pte_val(pfn_pte(__pa(pal_vaddr) >> PAGE_SHIFT, PAGE_KERNEL)),
375 		 IA64_GRANULE_SHIFT);
376 	ia64_set_psr(psr);		/* restore psr */
377 	ia64_srlz_i();
378 }
379 
380 void __init
381 efi_init (void)
382 {
383 	void *efi_map_start, *efi_map_end;
384 	efi_config_table_t *config_tables;
385 	efi_char16_t *c16;
386 	u64 efi_desc_size;
387 	char *cp, *end, vendor[100] = "unknown";
388 	extern char saved_command_line[];
389 	int i;
390 
391 	/* it's too early to be able to use the standard kernel command line support... */
392 	for (cp = saved_command_line; *cp; ) {
393 		if (memcmp(cp, "mem=", 4) == 0) {
394 			cp += 4;
395 			mem_limit = memparse(cp, &end);
396 			if (end != cp)
397 				break;
398 			cp = end;
399 		} else if (memcmp(cp, "max_addr=", 9) == 0) {
400 			cp += 9;
401 			max_addr = GRANULEROUNDDOWN(memparse(cp, &end));
402 			if (end != cp)
403 				break;
404 			cp = end;
405 		} else {
406 			while (*cp != ' ' && *cp)
407 				++cp;
408 			while (*cp == ' ')
409 				++cp;
410 		}
411 	}
412 	if (max_addr != ~0UL)
413 		printk(KERN_INFO "Ignoring memory above %luMB\n", max_addr >> 20);
414 
415 	efi.systab = __va(ia64_boot_param->efi_systab);
416 
417 	/*
418 	 * Verify the EFI Table
419 	 */
420 	if (efi.systab == NULL)
421 		panic("Woah! Can't find EFI system table.\n");
422 	if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
423 		panic("Woah! EFI system table signature incorrect\n");
424 	if ((efi.systab->hdr.revision ^ EFI_SYSTEM_TABLE_REVISION) >> 16 != 0)
425 		printk(KERN_WARNING "Warning: EFI system table major version mismatch: "
426 		       "got %d.%02d, expected %d.%02d\n",
427 		       efi.systab->hdr.revision >> 16, efi.systab->hdr.revision & 0xffff,
428 		       EFI_SYSTEM_TABLE_REVISION >> 16, EFI_SYSTEM_TABLE_REVISION & 0xffff);
429 
430 	config_tables = __va(efi.systab->tables);
431 
432 	/* Show what we know for posterity */
433 	c16 = __va(efi.systab->fw_vendor);
434 	if (c16) {
435 		for (i = 0;i < (int) sizeof(vendor) && *c16; ++i)
436 			vendor[i] = *c16++;
437 		vendor[i] = '\0';
438 	}
439 
440 	printk(KERN_INFO "EFI v%u.%.02u by %s:",
441 	       efi.systab->hdr.revision >> 16, efi.systab->hdr.revision & 0xffff, vendor);
442 
443 	for (i = 0; i < (int) efi.systab->nr_tables; i++) {
444 		if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
445 			efi.mps = __va(config_tables[i].table);
446 			printk(" MPS=0x%lx", config_tables[i].table);
447 		} else if (efi_guidcmp(config_tables[i].guid, ACPI_20_TABLE_GUID) == 0) {
448 			efi.acpi20 = __va(config_tables[i].table);
449 			printk(" ACPI 2.0=0x%lx", config_tables[i].table);
450 		} else if (efi_guidcmp(config_tables[i].guid, ACPI_TABLE_GUID) == 0) {
451 			efi.acpi = __va(config_tables[i].table);
452 			printk(" ACPI=0x%lx", config_tables[i].table);
453 		} else if (efi_guidcmp(config_tables[i].guid, SMBIOS_TABLE_GUID) == 0) {
454 			efi.smbios = __va(config_tables[i].table);
455 			printk(" SMBIOS=0x%lx", config_tables[i].table);
456 		} else if (efi_guidcmp(config_tables[i].guid, SAL_SYSTEM_TABLE_GUID) == 0) {
457 			efi.sal_systab = __va(config_tables[i].table);
458 			printk(" SALsystab=0x%lx", config_tables[i].table);
459 		} else if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
460 			efi.hcdp = __va(config_tables[i].table);
461 			printk(" HCDP=0x%lx", config_tables[i].table);
462 		}
463 	}
464 	printk("\n");
465 
466 	runtime = __va(efi.systab->runtime);
467 	efi.get_time = phys_get_time;
468 	efi.set_time = phys_set_time;
469 	efi.get_wakeup_time = phys_get_wakeup_time;
470 	efi.set_wakeup_time = phys_set_wakeup_time;
471 	efi.get_variable = phys_get_variable;
472 	efi.get_next_variable = phys_get_next_variable;
473 	efi.set_variable = phys_set_variable;
474 	efi.get_next_high_mono_count = phys_get_next_high_mono_count;
475 	efi.reset_system = phys_reset_system;
476 
477 	efi_map_start = __va(ia64_boot_param->efi_memmap);
478 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
479 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
480 
481 #if EFI_DEBUG
482 	/* print EFI memory map: */
483 	{
484 		efi_memory_desc_t *md;
485 		void *p;
486 
487 		for (i = 0, p = efi_map_start; p < efi_map_end; ++i, p += efi_desc_size) {
488 			md = p;
489 			printk("mem%02u: type=%u, attr=0x%lx, range=[0x%016lx-0x%016lx) (%luMB)\n",
490 			       i, md->type, md->attribute, md->phys_addr,
491 			       md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
492 			       md->num_pages >> (20 - EFI_PAGE_SHIFT));
493 		}
494 	}
495 #endif
496 
497 	efi_map_pal_code();
498 	efi_enter_virtual_mode();
499 }
500 
501 void
502 efi_enter_virtual_mode (void)
503 {
504 	void *efi_map_start, *efi_map_end, *p;
505 	efi_memory_desc_t *md;
506 	efi_status_t status;
507 	u64 efi_desc_size;
508 
509 	efi_map_start = __va(ia64_boot_param->efi_memmap);
510 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
511 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
512 
513 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
514 		md = p;
515 		if (md->attribute & EFI_MEMORY_RUNTIME) {
516 			/*
517 			 * Some descriptors have multiple bits set, so the order of
518 			 * the tests is relevant.
519 			 */
520 			if (md->attribute & EFI_MEMORY_WB) {
521 				md->virt_addr = (u64) __va(md->phys_addr);
522 			} else if (md->attribute & EFI_MEMORY_UC) {
523 				md->virt_addr = (u64) ioremap(md->phys_addr, 0);
524 			} else if (md->attribute & EFI_MEMORY_WC) {
525 #if 0
526 				md->virt_addr = ia64_remap(md->phys_addr, (_PAGE_A | _PAGE_P
527 									   | _PAGE_D
528 									   | _PAGE_MA_WC
529 									   | _PAGE_PL_0
530 									   | _PAGE_AR_RW));
531 #else
532 				printk(KERN_INFO "EFI_MEMORY_WC mapping\n");
533 				md->virt_addr = (u64) ioremap(md->phys_addr, 0);
534 #endif
535 			} else if (md->attribute & EFI_MEMORY_WT) {
536 #if 0
537 				md->virt_addr = ia64_remap(md->phys_addr, (_PAGE_A | _PAGE_P
538 									   | _PAGE_D | _PAGE_MA_WT
539 									   | _PAGE_PL_0
540 									   | _PAGE_AR_RW));
541 #else
542 				printk(KERN_INFO "EFI_MEMORY_WT mapping\n");
543 				md->virt_addr = (u64) ioremap(md->phys_addr, 0);
544 #endif
545 			}
546 		}
547 	}
548 
549 	status = efi_call_phys(__va(runtime->set_virtual_address_map),
550 			       ia64_boot_param->efi_memmap_size,
551 			       efi_desc_size, ia64_boot_param->efi_memdesc_version,
552 			       ia64_boot_param->efi_memmap);
553 	if (status != EFI_SUCCESS) {
554 		printk(KERN_WARNING "warning: unable to switch EFI into virtual mode "
555 		       "(status=%lu)\n", status);
556 		return;
557 	}
558 
559 	/*
560 	 * Now that EFI is in virtual mode, we call the EFI functions more efficiently:
561 	 */
562 	efi.get_time = virt_get_time;
563 	efi.set_time = virt_set_time;
564 	efi.get_wakeup_time = virt_get_wakeup_time;
565 	efi.set_wakeup_time = virt_set_wakeup_time;
566 	efi.get_variable = virt_get_variable;
567 	efi.get_next_variable = virt_get_next_variable;
568 	efi.set_variable = virt_set_variable;
569 	efi.get_next_high_mono_count = virt_get_next_high_mono_count;
570 	efi.reset_system = virt_reset_system;
571 }
572 
573 /*
574  * Walk the EFI memory map looking for the I/O port range.  There can only be one entry of
575  * this type, other I/O port ranges should be described via ACPI.
576  */
577 u64
578 efi_get_iobase (void)
579 {
580 	void *efi_map_start, *efi_map_end, *p;
581 	efi_memory_desc_t *md;
582 	u64 efi_desc_size;
583 
584 	efi_map_start = __va(ia64_boot_param->efi_memmap);
585 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
586 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
587 
588 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
589 		md = p;
590 		if (md->type == EFI_MEMORY_MAPPED_IO_PORT_SPACE) {
591 			if (md->attribute & EFI_MEMORY_UC)
592 				return md->phys_addr;
593 		}
594 	}
595 	return 0;
596 }
597 
598 u32
599 efi_mem_type (unsigned long phys_addr)
600 {
601 	void *efi_map_start, *efi_map_end, *p;
602 	efi_memory_desc_t *md;
603 	u64 efi_desc_size;
604 
605 	efi_map_start = __va(ia64_boot_param->efi_memmap);
606 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
607 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
608 
609 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
610 		md = p;
611 
612 		if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT))
613 			 return md->type;
614 	}
615 	return 0;
616 }
617 
618 u64
619 efi_mem_attributes (unsigned long phys_addr)
620 {
621 	void *efi_map_start, *efi_map_end, *p;
622 	efi_memory_desc_t *md;
623 	u64 efi_desc_size;
624 
625 	efi_map_start = __va(ia64_boot_param->efi_memmap);
626 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
627 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
628 
629 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
630 		md = p;
631 
632 		if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT))
633 			return md->attribute;
634 	}
635 	return 0;
636 }
637 EXPORT_SYMBOL(efi_mem_attributes);
638 
639 int
640 valid_phys_addr_range (unsigned long phys_addr, unsigned long *size)
641 {
642 	void *efi_map_start, *efi_map_end, *p;
643 	efi_memory_desc_t *md;
644 	u64 efi_desc_size;
645 
646 	efi_map_start = __va(ia64_boot_param->efi_memmap);
647 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
648 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
649 
650 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
651 		md = p;
652 
653 		if (phys_addr - md->phys_addr < (md->num_pages << EFI_PAGE_SHIFT)) {
654 			if (!(md->attribute & EFI_MEMORY_WB))
655 				return 0;
656 
657 			if (*size > md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - phys_addr)
658 				*size = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - phys_addr;
659 			return 1;
660 		}
661 	}
662 	return 0;
663 }
664 
665 int __init
666 efi_uart_console_only(void)
667 {
668 	efi_status_t status;
669 	char *s, name[] = "ConOut";
670 	efi_guid_t guid = EFI_GLOBAL_VARIABLE_GUID;
671 	efi_char16_t *utf16, name_utf16[32];
672 	unsigned char data[1024];
673 	unsigned long size = sizeof(data);
674 	struct efi_generic_dev_path *hdr, *end_addr;
675 	int uart = 0;
676 
677 	/* Convert to UTF-16 */
678 	utf16 = name_utf16;
679 	s = name;
680 	while (*s)
681 		*utf16++ = *s++ & 0x7f;
682 	*utf16 = 0;
683 
684 	status = efi.get_variable(name_utf16, &guid, NULL, &size, data);
685 	if (status != EFI_SUCCESS) {
686 		printk(KERN_ERR "No EFI %s variable?\n", name);
687 		return 0;
688 	}
689 
690 	hdr = (struct efi_generic_dev_path *) data;
691 	end_addr = (struct efi_generic_dev_path *) ((u8 *) data + size);
692 	while (hdr < end_addr) {
693 		if (hdr->type == EFI_DEV_MSG &&
694 		    hdr->sub_type == EFI_DEV_MSG_UART)
695 			uart = 1;
696 		else if (hdr->type == EFI_DEV_END_PATH ||
697 			  hdr->type == EFI_DEV_END_PATH2) {
698 			if (!uart)
699 				return 0;
700 			if (hdr->sub_type == EFI_DEV_END_ENTIRE)
701 				return 1;
702 			uart = 0;
703 		}
704 		hdr = (struct efi_generic_dev_path *) ((u8 *) hdr + hdr->length);
705 	}
706 	printk(KERN_ERR "Malformed %s value\n", name);
707 	return 0;
708 }
709 
710 #define efi_md_size(md)	(md->num_pages << EFI_PAGE_SHIFT)
711 
712 static inline u64
713 kmd_end(kern_memdesc_t *kmd)
714 {
715 	return (kmd->start + (kmd->num_pages << EFI_PAGE_SHIFT));
716 }
717 
718 static inline u64
719 efi_md_end(efi_memory_desc_t *md)
720 {
721 	return (md->phys_addr + efi_md_size(md));
722 }
723 
724 static inline int
725 efi_wb(efi_memory_desc_t *md)
726 {
727 	return (md->attribute & EFI_MEMORY_WB);
728 }
729 
730 static inline int
731 efi_uc(efi_memory_desc_t *md)
732 {
733 	return (md->attribute & EFI_MEMORY_UC);
734 }
735 
736 /*
737  * Look for the first granule aligned memory descriptor memory
738  * that is big enough to hold EFI memory map. Make sure this
739  * descriptor is atleast granule sized so it does not get trimmed
740  */
741 struct kern_memdesc *
742 find_memmap_space (void)
743 {
744 	u64	contig_low=0, contig_high=0;
745 	u64	as = 0, ae;
746 	void *efi_map_start, *efi_map_end, *p, *q;
747 	efi_memory_desc_t *md, *pmd = NULL, *check_md;
748 	u64	space_needed, efi_desc_size;
749 	unsigned long total_mem = 0;
750 
751 	efi_map_start = __va(ia64_boot_param->efi_memmap);
752 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
753 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
754 
755 	/*
756 	 * Worst case: we need 3 kernel descriptors for each efi descriptor
757 	 * (if every entry has a WB part in the middle, and UC head and tail),
758 	 * plus one for the end marker.
759 	 */
760 	space_needed = sizeof(kern_memdesc_t) *
761 		(3 * (ia64_boot_param->efi_memmap_size/efi_desc_size) + 1);
762 
763 	for (p = efi_map_start; p < efi_map_end; pmd = md, p += efi_desc_size) {
764 		md = p;
765 		if (!efi_wb(md)) {
766 			continue;
767 		}
768 		if (pmd == NULL || !efi_wb(pmd) || efi_md_end(pmd) != md->phys_addr) {
769 			contig_low = GRANULEROUNDUP(md->phys_addr);
770 			contig_high = efi_md_end(md);
771 			for (q = p + efi_desc_size; q < efi_map_end; q += efi_desc_size) {
772 				check_md = q;
773 				if (!efi_wb(check_md))
774 					break;
775 				if (contig_high != check_md->phys_addr)
776 					break;
777 				contig_high = efi_md_end(check_md);
778 			}
779 			contig_high = GRANULEROUNDDOWN(contig_high);
780 		}
781 		if (!is_available_memory(md) || md->type == EFI_LOADER_DATA)
782 			continue;
783 
784 		/* Round ends inward to granule boundaries */
785 		as = max(contig_low, md->phys_addr);
786 		ae = min(contig_high, efi_md_end(md));
787 
788 		/* keep within max_addr= command line arg */
789 		ae = min(ae, max_addr);
790 		if (ae <= as)
791 			continue;
792 
793 		/* avoid going over mem= command line arg */
794 		if (total_mem + (ae - as) > mem_limit)
795 			ae -= total_mem + (ae - as) - mem_limit;
796 
797 		if (ae <= as)
798 			continue;
799 
800 		if (ae - as > space_needed)
801 			break;
802 	}
803 	if (p >= efi_map_end)
804 		panic("Can't allocate space for kernel memory descriptors");
805 
806 	return __va(as);
807 }
808 
809 /*
810  * Walk the EFI memory map and gather all memory available for kernel
811  * to use.  We can allocate partial granules only if the unavailable
812  * parts exist, and are WB.
813  */
814 void
815 efi_memmap_init(unsigned long *s, unsigned long *e)
816 {
817 	struct kern_memdesc *k, *prev = 0;
818 	u64	contig_low=0, contig_high=0;
819 	u64	as, ae, lim;
820 	void *efi_map_start, *efi_map_end, *p, *q;
821 	efi_memory_desc_t *md, *pmd = NULL, *check_md;
822 	u64	efi_desc_size;
823 	unsigned long total_mem = 0;
824 
825 	k = kern_memmap = find_memmap_space();
826 
827 	efi_map_start = __va(ia64_boot_param->efi_memmap);
828 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
829 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
830 
831 	for (p = efi_map_start; p < efi_map_end; pmd = md, p += efi_desc_size) {
832 		md = p;
833 		if (!efi_wb(md)) {
834 			if (efi_uc(md) && (md->type == EFI_CONVENTIONAL_MEMORY ||
835 				    	   md->type == EFI_BOOT_SERVICES_DATA)) {
836 				k->attribute = EFI_MEMORY_UC;
837 				k->start = md->phys_addr;
838 				k->num_pages = md->num_pages;
839 				k++;
840 			}
841 			continue;
842 		}
843 		if (pmd == NULL || !efi_wb(pmd) || efi_md_end(pmd) != md->phys_addr) {
844 			contig_low = GRANULEROUNDUP(md->phys_addr);
845 			contig_high = efi_md_end(md);
846 			for (q = p + efi_desc_size; q < efi_map_end; q += efi_desc_size) {
847 				check_md = q;
848 				if (!efi_wb(check_md))
849 					break;
850 				if (contig_high != check_md->phys_addr)
851 					break;
852 				contig_high = efi_md_end(check_md);
853 			}
854 			contig_high = GRANULEROUNDDOWN(contig_high);
855 		}
856 		if (!is_available_memory(md))
857 			continue;
858 
859 		/*
860 		 * Round ends inward to granule boundaries
861 		 * Give trimmings to uncached allocator
862 		 */
863 		if (md->phys_addr < contig_low) {
864 			lim = min(efi_md_end(md), contig_low);
865 			if (efi_uc(md)) {
866 				if (k > kern_memmap && (k-1)->attribute == EFI_MEMORY_UC &&
867 				    kmd_end(k-1) == md->phys_addr) {
868 					(k-1)->num_pages += (lim - md->phys_addr) >> EFI_PAGE_SHIFT;
869 				} else {
870 					k->attribute = EFI_MEMORY_UC;
871 					k->start = md->phys_addr;
872 					k->num_pages = (lim - md->phys_addr) >> EFI_PAGE_SHIFT;
873 					k++;
874 				}
875 			}
876 			as = contig_low;
877 		} else
878 			as = md->phys_addr;
879 
880 		if (efi_md_end(md) > contig_high) {
881 			lim = max(md->phys_addr, contig_high);
882 			if (efi_uc(md)) {
883 				if (lim == md->phys_addr && k > kern_memmap &&
884 				    (k-1)->attribute == EFI_MEMORY_UC &&
885 				    kmd_end(k-1) == md->phys_addr) {
886 					(k-1)->num_pages += md->num_pages;
887 				} else {
888 					k->attribute = EFI_MEMORY_UC;
889 					k->start = lim;
890 					k->num_pages = (efi_md_end(md) - lim) >> EFI_PAGE_SHIFT;
891 					k++;
892 				}
893 			}
894 			ae = contig_high;
895 		} else
896 			ae = efi_md_end(md);
897 
898 		/* keep within max_addr= command line arg */
899 		ae = min(ae, max_addr);
900 		if (ae <= as)
901 			continue;
902 
903 		/* avoid going over mem= command line arg */
904 		if (total_mem + (ae - as) > mem_limit)
905 			ae -= total_mem + (ae - as) - mem_limit;
906 
907 		if (ae <= as)
908 			continue;
909 		if (prev && kmd_end(prev) == md->phys_addr) {
910 			prev->num_pages += (ae - as) >> EFI_PAGE_SHIFT;
911 			total_mem += ae - as;
912 			continue;
913 		}
914 		k->attribute = EFI_MEMORY_WB;
915 		k->start = as;
916 		k->num_pages = (ae - as) >> EFI_PAGE_SHIFT;
917 		total_mem += ae - as;
918 		prev = k++;
919 	}
920 	k->start = ~0L; /* end-marker */
921 
922 	/* reserve the memory we are using for kern_memmap */
923 	*s = (u64)kern_memmap;
924 	*e = (u64)++k;
925 }
926 
927 void
928 efi_initialize_iomem_resources(struct resource *code_resource,
929 			       struct resource *data_resource)
930 {
931 	struct resource *res;
932 	void *efi_map_start, *efi_map_end, *p;
933 	efi_memory_desc_t *md;
934 	u64 efi_desc_size;
935 	char *name;
936 	unsigned long flags;
937 
938 	efi_map_start = __va(ia64_boot_param->efi_memmap);
939 	efi_map_end   = efi_map_start + ia64_boot_param->efi_memmap_size;
940 	efi_desc_size = ia64_boot_param->efi_memdesc_size;
941 
942 	res = NULL;
943 
944 	for (p = efi_map_start; p < efi_map_end; p += efi_desc_size) {
945 		md = p;
946 
947 		if (md->num_pages == 0) /* should not happen */
948 			continue;
949 
950 		flags = IORESOURCE_MEM;
951 		switch (md->type) {
952 
953 			case EFI_MEMORY_MAPPED_IO:
954 			case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
955 				continue;
956 
957 			case EFI_LOADER_CODE:
958 			case EFI_LOADER_DATA:
959 			case EFI_BOOT_SERVICES_DATA:
960 			case EFI_BOOT_SERVICES_CODE:
961 			case EFI_CONVENTIONAL_MEMORY:
962 				if (md->attribute & EFI_MEMORY_WP) {
963 					name = "System ROM";
964 					flags |= IORESOURCE_READONLY;
965 				} else {
966 					name = "System RAM";
967 				}
968 				break;
969 
970 			case EFI_ACPI_MEMORY_NVS:
971 				name = "ACPI Non-volatile Storage";
972 				flags |= IORESOURCE_BUSY;
973 				break;
974 
975 			case EFI_UNUSABLE_MEMORY:
976 				name = "reserved";
977 				flags |= IORESOURCE_BUSY | IORESOURCE_DISABLED;
978 				break;
979 
980 			case EFI_RESERVED_TYPE:
981 			case EFI_RUNTIME_SERVICES_CODE:
982 			case EFI_RUNTIME_SERVICES_DATA:
983 			case EFI_ACPI_RECLAIM_MEMORY:
984 			default:
985 				name = "reserved";
986 				flags |= IORESOURCE_BUSY;
987 				break;
988 		}
989 
990 		if ((res = kcalloc(1, sizeof(struct resource), GFP_KERNEL)) == NULL) {
991 			printk(KERN_ERR "failed to alocate resource for iomem\n");
992 			return;
993 		}
994 
995 		res->name = name;
996 		res->start = md->phys_addr;
997 		res->end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
998 		res->flags = flags;
999 
1000 		if (insert_resource(&iomem_resource, res) < 0)
1001 			kfree(res);
1002 		else {
1003 			/*
1004 			 * We don't know which region contains
1005 			 * kernel data so we try it repeatedly and
1006 			 * let the resource manager test it.
1007 			 */
1008 			insert_resource(res, code_resource);
1009 			insert_resource(res, data_resource);
1010 		}
1011 	}
1012 }
1013