sched: make early bootup sched_clock() use safer
[wrt350n-kernel.git] / arch / x86 / kernel / efi.c
blob759e02bec0708f955764907ec380e6eb737c6dfa
1 /*
2 * Common EFI (Extensible Firmware Interface) support functions
3 * Based on Extensible Firmware Interface Specification version 1.0
5 * Copyright (C) 1999 VA Linux Systems
6 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
7 * Copyright (C) 1999-2002 Hewlett-Packard Co.
8 * David Mosberger-Tang <davidm@hpl.hp.com>
9 * Stephane Eranian <eranian@hpl.hp.com>
10 * Copyright (C) 2005-2008 Intel Co.
11 * Fenghua Yu <fenghua.yu@intel.com>
12 * Bibo Mao <bibo.mao@intel.com>
13 * Chandramouli Narayanan <mouli@linux.intel.com>
14 * Huang Ying <ying.huang@intel.com>
16 * Copied from efi_32.c to eliminate the duplicated code between EFI
17 * 32/64 support code. --ying 2007-10-26
19 * All EFI Runtime Services are not implemented yet as EFI only
20 * supports physical mode addressing on SoftSDV. This is to be fixed
21 * in a future version. --drummond 1999-07-20
23 * Implemented EFI runtime services and virtual mode calls. --davidm
25 * Goutham Rao: <goutham.rao@intel.com>
26 * Skip non-WB memory and ignore empty memory ranges.
29 #include <linux/kernel.h>
30 #include <linux/init.h>
31 #include <linux/efi.h>
32 #include <linux/bootmem.h>
33 #include <linux/spinlock.h>
34 #include <linux/uaccess.h>
35 #include <linux/time.h>
36 #include <linux/io.h>
37 #include <linux/reboot.h>
38 #include <linux/bcd.h>
40 #include <asm/setup.h>
41 #include <asm/efi.h>
42 #include <asm/time.h>
43 #include <asm/cacheflush.h>
44 #include <asm/tlbflush.h>
46 #define EFI_DEBUG 1
47 #define PFX "EFI: "
49 int efi_enabled;
50 EXPORT_SYMBOL(efi_enabled);
52 struct efi efi;
53 EXPORT_SYMBOL(efi);
55 struct efi_memory_map memmap;
57 static struct efi efi_phys __initdata;
58 static efi_system_table_t efi_systab __initdata;
60 static int __init setup_noefi(char *arg)
62 efi_enabled = 0;
63 return 0;
65 early_param("noefi", setup_noefi);
67 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
69 return efi_call_virt2(get_time, tm, tc);
72 static efi_status_t virt_efi_set_time(efi_time_t *tm)
74 return efi_call_virt1(set_time, tm);
77 static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
78 efi_bool_t *pending,
79 efi_time_t *tm)
81 return efi_call_virt3(get_wakeup_time,
82 enabled, pending, tm);
85 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
87 return efi_call_virt2(set_wakeup_time,
88 enabled, tm);
91 static efi_status_t virt_efi_get_variable(efi_char16_t *name,
92 efi_guid_t *vendor,
93 u32 *attr,
94 unsigned long *data_size,
95 void *data)
97 return efi_call_virt5(get_variable,
98 name, vendor, attr,
99 data_size, data);
102 static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
103 efi_char16_t *name,
104 efi_guid_t *vendor)
106 return efi_call_virt3(get_next_variable,
107 name_size, name, vendor);
110 static efi_status_t virt_efi_set_variable(efi_char16_t *name,
111 efi_guid_t *vendor,
112 unsigned long attr,
113 unsigned long data_size,
114 void *data)
116 return efi_call_virt5(set_variable,
117 name, vendor, attr,
118 data_size, data);
121 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
123 return efi_call_virt1(get_next_high_mono_count, count);
126 static void virt_efi_reset_system(int reset_type,
127 efi_status_t status,
128 unsigned long data_size,
129 efi_char16_t *data)
131 efi_call_virt4(reset_system, reset_type, status,
132 data_size, data);
135 static efi_status_t virt_efi_set_virtual_address_map(
136 unsigned long memory_map_size,
137 unsigned long descriptor_size,
138 u32 descriptor_version,
139 efi_memory_desc_t *virtual_map)
141 return efi_call_virt4(set_virtual_address_map,
142 memory_map_size, descriptor_size,
143 descriptor_version, virtual_map);
146 static efi_status_t __init phys_efi_set_virtual_address_map(
147 unsigned long memory_map_size,
148 unsigned long descriptor_size,
149 u32 descriptor_version,
150 efi_memory_desc_t *virtual_map)
152 efi_status_t status;
154 efi_call_phys_prelog();
155 status = efi_call_phys4(efi_phys.set_virtual_address_map,
156 memory_map_size, descriptor_size,
157 descriptor_version, virtual_map);
158 efi_call_phys_epilog();
159 return status;
162 static efi_status_t __init phys_efi_get_time(efi_time_t *tm,
163 efi_time_cap_t *tc)
165 efi_status_t status;
167 efi_call_phys_prelog();
168 status = efi_call_phys2(efi_phys.get_time, tm, tc);
169 efi_call_phys_epilog();
170 return status;
173 int efi_set_rtc_mmss(unsigned long nowtime)
175 int real_seconds, real_minutes;
176 efi_status_t status;
177 efi_time_t eft;
178 efi_time_cap_t cap;
180 status = efi.get_time(&eft, &cap);
181 if (status != EFI_SUCCESS) {
182 printk(KERN_ERR "Oops: efitime: can't read time!\n");
183 return -1;
186 real_seconds = nowtime % 60;
187 real_minutes = nowtime / 60;
188 if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
189 real_minutes += 30;
190 real_minutes %= 60;
191 eft.minute = real_minutes;
192 eft.second = real_seconds;
194 status = efi.set_time(&eft);
195 if (status != EFI_SUCCESS) {
196 printk(KERN_ERR "Oops: efitime: can't write time!\n");
197 return -1;
199 return 0;
202 unsigned long efi_get_time(void)
204 efi_status_t status;
205 efi_time_t eft;
206 efi_time_cap_t cap;
208 status = efi.get_time(&eft, &cap);
209 if (status != EFI_SUCCESS)
210 printk(KERN_ERR "Oops: efitime: can't read time!\n");
212 return mktime(eft.year, eft.month, eft.day, eft.hour,
213 eft.minute, eft.second);
216 #if EFI_DEBUG
217 static void __init print_efi_memmap(void)
219 efi_memory_desc_t *md;
220 void *p;
221 int i;
223 for (p = memmap.map, i = 0;
224 p < memmap.map_end;
225 p += memmap.desc_size, i++) {
226 md = p;
227 printk(KERN_INFO PFX "mem%02u: type=%u, attr=0x%llx, "
228 "range=[0x%016llx-0x%016llx) (%lluMB)\n",
229 i, md->type, md->attribute, md->phys_addr,
230 md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
231 (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
234 #endif /* EFI_DEBUG */
236 void __init efi_init(void)
238 efi_config_table_t *config_tables;
239 efi_runtime_services_t *runtime;
240 efi_char16_t *c16;
241 char vendor[100] = "unknown";
242 int i = 0;
243 void *tmp;
245 #ifdef CONFIG_X86_32
246 efi_phys.systab = (efi_system_table_t *)boot_params.efi_info.efi_systab;
247 memmap.phys_map = (void *)boot_params.efi_info.efi_memmap;
248 #else
249 efi_phys.systab = (efi_system_table_t *)
250 (boot_params.efi_info.efi_systab |
251 ((__u64)boot_params.efi_info.efi_systab_hi<<32));
252 memmap.phys_map = (void *)
253 (boot_params.efi_info.efi_memmap |
254 ((__u64)boot_params.efi_info.efi_memmap_hi<<32));
255 #endif
256 memmap.nr_map = boot_params.efi_info.efi_memmap_size /
257 boot_params.efi_info.efi_memdesc_size;
258 memmap.desc_version = boot_params.efi_info.efi_memdesc_version;
259 memmap.desc_size = boot_params.efi_info.efi_memdesc_size;
261 efi.systab = early_ioremap((unsigned long)efi_phys.systab,
262 sizeof(efi_system_table_t));
263 if (efi.systab == NULL)
264 printk(KERN_ERR "Couldn't map the EFI system table!\n");
265 memcpy(&efi_systab, efi.systab, sizeof(efi_system_table_t));
266 early_iounmap(efi.systab, sizeof(efi_system_table_t));
267 efi.systab = &efi_systab;
270 * Verify the EFI Table
272 if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
273 printk(KERN_ERR "EFI system table signature incorrect!\n");
274 if ((efi.systab->hdr.revision >> 16) == 0)
275 printk(KERN_ERR "Warning: EFI system table version "
276 "%d.%02d, expected 1.00 or greater!\n",
277 efi.systab->hdr.revision >> 16,
278 efi.systab->hdr.revision & 0xffff);
281 * Show what we know for posterity
283 c16 = tmp = early_ioremap(efi.systab->fw_vendor, 2);
284 if (c16) {
285 for (i = 0; i < sizeof(vendor) && *c16; ++i)
286 vendor[i] = *c16++;
287 vendor[i] = '\0';
288 } else
289 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
290 early_iounmap(tmp, 2);
292 printk(KERN_INFO "EFI v%u.%.02u by %s \n",
293 efi.systab->hdr.revision >> 16,
294 efi.systab->hdr.revision & 0xffff, vendor);
297 * Let's see what config tables the firmware passed to us.
299 config_tables = early_ioremap(
300 efi.systab->tables,
301 efi.systab->nr_tables * sizeof(efi_config_table_t));
302 if (config_tables == NULL)
303 printk(KERN_ERR "Could not map EFI Configuration Table!\n");
305 printk(KERN_INFO);
306 for (i = 0; i < efi.systab->nr_tables; i++) {
307 if (!efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID)) {
308 efi.mps = config_tables[i].table;
309 printk(" MPS=0x%lx ", config_tables[i].table);
310 } else if (!efi_guidcmp(config_tables[i].guid,
311 ACPI_20_TABLE_GUID)) {
312 efi.acpi20 = config_tables[i].table;
313 printk(" ACPI 2.0=0x%lx ", config_tables[i].table);
314 } else if (!efi_guidcmp(config_tables[i].guid,
315 ACPI_TABLE_GUID)) {
316 efi.acpi = config_tables[i].table;
317 printk(" ACPI=0x%lx ", config_tables[i].table);
318 } else if (!efi_guidcmp(config_tables[i].guid,
319 SMBIOS_TABLE_GUID)) {
320 efi.smbios = config_tables[i].table;
321 printk(" SMBIOS=0x%lx ", config_tables[i].table);
322 } else if (!efi_guidcmp(config_tables[i].guid,
323 HCDP_TABLE_GUID)) {
324 efi.hcdp = config_tables[i].table;
325 printk(" HCDP=0x%lx ", config_tables[i].table);
326 } else if (!efi_guidcmp(config_tables[i].guid,
327 UGA_IO_PROTOCOL_GUID)) {
328 efi.uga = config_tables[i].table;
329 printk(" UGA=0x%lx ", config_tables[i].table);
332 printk("\n");
333 early_iounmap(config_tables,
334 efi.systab->nr_tables * sizeof(efi_config_table_t));
337 * Check out the runtime services table. We need to map
338 * the runtime services table so that we can grab the physical
339 * address of several of the EFI runtime functions, needed to
340 * set the firmware into virtual mode.
342 runtime = early_ioremap((unsigned long)efi.systab->runtime,
343 sizeof(efi_runtime_services_t));
344 if (runtime != NULL) {
346 * We will only need *early* access to the following
347 * two EFI runtime services before set_virtual_address_map
348 * is invoked.
350 efi_phys.get_time = (efi_get_time_t *)runtime->get_time;
351 efi_phys.set_virtual_address_map =
352 (efi_set_virtual_address_map_t *)
353 runtime->set_virtual_address_map;
355 * Make efi_get_time can be called before entering
356 * virtual mode.
358 efi.get_time = phys_efi_get_time;
359 } else
360 printk(KERN_ERR "Could not map the EFI runtime service "
361 "table!\n");
362 early_iounmap(runtime, sizeof(efi_runtime_services_t));
364 /* Map the EFI memory map */
365 memmap.map = early_ioremap((unsigned long)memmap.phys_map,
366 memmap.nr_map * memmap.desc_size);
367 if (memmap.map == NULL)
368 printk(KERN_ERR "Could not map the EFI memory map!\n");
369 memmap.map_end = memmap.map + (memmap.nr_map * memmap.desc_size);
370 if (memmap.desc_size != sizeof(efi_memory_desc_t))
371 printk(KERN_WARNING "Kernel-defined memdesc"
372 "doesn't match the one from EFI!\n");
374 /* Setup for EFI runtime service */
375 reboot_type = BOOT_EFI;
377 #if EFI_DEBUG
378 print_efi_memmap();
379 #endif
382 static void __init runtime_code_page_mkexec(void)
384 efi_memory_desc_t *md;
385 void *p;
387 /* Make EFI runtime service code area executable */
388 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
389 md = p;
391 if (md->type != EFI_RUNTIME_SERVICES_CODE)
392 continue;
394 set_memory_x(md->virt_addr, md->num_pages);
399 * This function will switch the EFI runtime services to virtual mode.
400 * Essentially, look through the EFI memmap and map every region that
401 * has the runtime attribute bit set in its memory descriptor and update
402 * that memory descriptor with the virtual address obtained from ioremap().
403 * This enables the runtime services to be called without having to
404 * thunk back into physical mode for every invocation.
406 void __init efi_enter_virtual_mode(void)
408 efi_memory_desc_t *md;
409 efi_status_t status;
410 unsigned long size;
411 u64 end, systab;
412 void *p, *va;
414 efi.systab = NULL;
415 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
416 md = p;
417 if (!(md->attribute & EFI_MEMORY_RUNTIME))
418 continue;
420 size = md->num_pages << EFI_PAGE_SHIFT;
421 end = md->phys_addr + size;
423 if ((end >> PAGE_SHIFT) <= max_pfn_mapped)
424 va = __va(md->phys_addr);
425 else
426 va = efi_ioremap(md->phys_addr, size);
428 md->virt_addr = (u64) (unsigned long) va;
430 if (!va) {
431 printk(KERN_ERR PFX "ioremap of 0x%llX failed!\n",
432 (unsigned long long)md->phys_addr);
433 continue;
436 if (!(md->attribute & EFI_MEMORY_WB))
437 set_memory_uc(md->virt_addr, md->num_pages);
439 systab = (u64) (unsigned long) efi_phys.systab;
440 if (md->phys_addr <= systab && systab < end) {
441 systab += md->virt_addr - md->phys_addr;
442 efi.systab = (efi_system_table_t *) (unsigned long) systab;
446 BUG_ON(!efi.systab);
448 status = phys_efi_set_virtual_address_map(
449 memmap.desc_size * memmap.nr_map,
450 memmap.desc_size,
451 memmap.desc_version,
452 memmap.phys_map);
454 if (status != EFI_SUCCESS) {
455 printk(KERN_ALERT "Unable to switch EFI into virtual mode "
456 "(status=%lx)!\n", status);
457 panic("EFI call to SetVirtualAddressMap() failed!");
461 * Now that EFI is in virtual mode, update the function
462 * pointers in the runtime service table to the new virtual addresses.
464 * Call EFI services through wrapper functions.
466 efi.get_time = virt_efi_get_time;
467 efi.set_time = virt_efi_set_time;
468 efi.get_wakeup_time = virt_efi_get_wakeup_time;
469 efi.set_wakeup_time = virt_efi_set_wakeup_time;
470 efi.get_variable = virt_efi_get_variable;
471 efi.get_next_variable = virt_efi_get_next_variable;
472 efi.set_variable = virt_efi_set_variable;
473 efi.get_next_high_mono_count = virt_efi_get_next_high_mono_count;
474 efi.reset_system = virt_efi_reset_system;
475 efi.set_virtual_address_map = virt_efi_set_virtual_address_map;
476 if (__supported_pte_mask & _PAGE_NX)
477 runtime_code_page_mkexec();
478 early_iounmap(memmap.map, memmap.nr_map * memmap.desc_size);
479 memmap.map = NULL;
483 * Convenience functions to obtain memory types and attributes
485 u32 efi_mem_type(unsigned long phys_addr)
487 efi_memory_desc_t *md;
488 void *p;
490 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
491 md = p;
492 if ((md->phys_addr <= phys_addr) &&
493 (phys_addr < (md->phys_addr +
494 (md->num_pages << EFI_PAGE_SHIFT))))
495 return md->type;
497 return 0;
500 u64 efi_mem_attributes(unsigned long phys_addr)
502 efi_memory_desc_t *md;
503 void *p;
505 for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
506 md = p;
507 if ((md->phys_addr <= phys_addr) &&
508 (phys_addr < (md->phys_addr +
509 (md->num_pages << EFI_PAGE_SHIFT))))
510 return md->attribute;
512 return 0;