2 * efi.c - EFI subsystem
4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
6 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
8 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
9 * allowing the efivarfs to be mounted or the efivars module to be loaded.
10 * The existance of /sys/firmware/efi may also be used by userspace to
11 * determine that the system supports EFI.
13 * This file is released under the GPLv2.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/kobject.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/device.h>
22 #include <linux/efi.h>
24 #include <linux/of_fdt.h>
26 #include <linux/platform_device.h>
28 struct efi __read_mostly efi
= {
29 .mps
= EFI_INVALID_TABLE_ADDR
,
30 .acpi
= EFI_INVALID_TABLE_ADDR
,
31 .acpi20
= EFI_INVALID_TABLE_ADDR
,
32 .smbios
= EFI_INVALID_TABLE_ADDR
,
33 .sal_systab
= EFI_INVALID_TABLE_ADDR
,
34 .boot_info
= EFI_INVALID_TABLE_ADDR
,
35 .hcdp
= EFI_INVALID_TABLE_ADDR
,
36 .uga
= EFI_INVALID_TABLE_ADDR
,
37 .uv_systab
= EFI_INVALID_TABLE_ADDR
,
38 .fw_vendor
= EFI_INVALID_TABLE_ADDR
,
39 .runtime
= EFI_INVALID_TABLE_ADDR
,
40 .config_table
= EFI_INVALID_TABLE_ADDR
,
44 static bool disable_runtime
;
45 static int __init
setup_noefi(char *arg
)
47 disable_runtime
= true;
50 early_param("noefi", setup_noefi
);
52 bool efi_runtime_disabled(void)
54 return disable_runtime
;
57 static int __init
parse_efi_cmdline(char *str
)
59 if (parse_option_str(str
, "noruntime"))
60 disable_runtime
= true;
64 early_param("efi", parse_efi_cmdline
);
66 static struct kobject
*efi_kobj
;
67 static struct kobject
*efivars_kobj
;
70 * Let's not leave out systab information that snuck into
73 static ssize_t
systab_show(struct kobject
*kobj
,
74 struct kobj_attribute
*attr
, char *buf
)
81 if (efi
.mps
!= EFI_INVALID_TABLE_ADDR
)
82 str
+= sprintf(str
, "MPS=0x%lx\n", efi
.mps
);
83 if (efi
.acpi20
!= EFI_INVALID_TABLE_ADDR
)
84 str
+= sprintf(str
, "ACPI20=0x%lx\n", efi
.acpi20
);
85 if (efi
.acpi
!= EFI_INVALID_TABLE_ADDR
)
86 str
+= sprintf(str
, "ACPI=0x%lx\n", efi
.acpi
);
87 if (efi
.smbios
!= EFI_INVALID_TABLE_ADDR
)
88 str
+= sprintf(str
, "SMBIOS=0x%lx\n", efi
.smbios
);
89 if (efi
.hcdp
!= EFI_INVALID_TABLE_ADDR
)
90 str
+= sprintf(str
, "HCDP=0x%lx\n", efi
.hcdp
);
91 if (efi
.boot_info
!= EFI_INVALID_TABLE_ADDR
)
92 str
+= sprintf(str
, "BOOTINFO=0x%lx\n", efi
.boot_info
);
93 if (efi
.uga
!= EFI_INVALID_TABLE_ADDR
)
94 str
+= sprintf(str
, "UGA=0x%lx\n", efi
.uga
);
99 static struct kobj_attribute efi_attr_systab
=
100 __ATTR(systab
, 0400, systab_show
, NULL
);
102 #define EFI_FIELD(var) efi.var
104 #define EFI_ATTR_SHOW(name) \
105 static ssize_t name##_show(struct kobject *kobj, \
106 struct kobj_attribute *attr, char *buf) \
108 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
111 EFI_ATTR_SHOW(fw_vendor
);
112 EFI_ATTR_SHOW(runtime
);
113 EFI_ATTR_SHOW(config_table
);
115 static struct kobj_attribute efi_attr_fw_vendor
= __ATTR_RO(fw_vendor
);
116 static struct kobj_attribute efi_attr_runtime
= __ATTR_RO(runtime
);
117 static struct kobj_attribute efi_attr_config_table
= __ATTR_RO(config_table
);
119 static struct attribute
*efi_subsys_attrs
[] = {
120 &efi_attr_systab
.attr
,
121 &efi_attr_fw_vendor
.attr
,
122 &efi_attr_runtime
.attr
,
123 &efi_attr_config_table
.attr
,
127 static umode_t
efi_attr_is_visible(struct kobject
*kobj
,
128 struct attribute
*attr
, int n
)
130 if (attr
== &efi_attr_fw_vendor
.attr
) {
131 if (efi_enabled(EFI_PARAVIRT
) ||
132 efi
.fw_vendor
== EFI_INVALID_TABLE_ADDR
)
134 } else if (attr
== &efi_attr_runtime
.attr
) {
135 if (efi
.runtime
== EFI_INVALID_TABLE_ADDR
)
137 } else if (attr
== &efi_attr_config_table
.attr
) {
138 if (efi
.config_table
== EFI_INVALID_TABLE_ADDR
)
145 static struct attribute_group efi_subsys_attr_group
= {
146 .attrs
= efi_subsys_attrs
,
147 .is_visible
= efi_attr_is_visible
,
150 static struct efivars generic_efivars
;
151 static struct efivar_operations generic_ops
;
153 static int generic_ops_register(void)
155 generic_ops
.get_variable
= efi
.get_variable
;
156 generic_ops
.set_variable
= efi
.set_variable
;
157 generic_ops
.get_next_variable
= efi
.get_next_variable
;
158 generic_ops
.query_variable_store
= efi_query_variable_store
;
160 return efivars_register(&generic_efivars
, &generic_ops
, efi_kobj
);
163 static void generic_ops_unregister(void)
165 efivars_unregister(&generic_efivars
);
169 * We register the efi subsystem with the firmware subsystem and the
170 * efivars subsystem with the efi subsystem, if the system was booted with
173 static int __init
efisubsys_init(void)
177 if (!efi_enabled(EFI_BOOT
))
180 /* We register the efi directory at /sys/firmware/efi */
181 efi_kobj
= kobject_create_and_add("efi", firmware_kobj
);
183 pr_err("efi: Firmware registration failed.\n");
187 error
= generic_ops_register();
191 error
= sysfs_create_group(efi_kobj
, &efi_subsys_attr_group
);
193 pr_err("efi: Sysfs attribute export failed with error %d.\n",
198 error
= efi_runtime_map_init(efi_kobj
);
200 goto err_remove_group
;
202 /* and the standard mountpoint for efivarfs */
203 efivars_kobj
= kobject_create_and_add("efivars", efi_kobj
);
205 pr_err("efivars: Subsystem registration failed.\n");
207 goto err_remove_group
;
213 sysfs_remove_group(efi_kobj
, &efi_subsys_attr_group
);
215 generic_ops_unregister();
217 kobject_put(efi_kobj
);
221 subsys_initcall(efisubsys_init
);
225 * We can't ioremap data in EFI boot services RAM, because we've already mapped
226 * it as RAM. So, look it up in the existing EFI memory map instead. Only
227 * callable after efi_enter_virtual_mode and before efi_free_boot_services.
229 void __iomem
*efi_lookup_mapped_addr(u64 phys_addr
)
231 struct efi_memory_map
*map
;
236 if (WARN_ON(!map
->map
))
238 for (p
= map
->map
; p
< map
->map_end
; p
+= map
->desc_size
) {
239 efi_memory_desc_t
*md
= p
;
240 u64 size
= md
->num_pages
<< EFI_PAGE_SHIFT
;
241 u64 end
= md
->phys_addr
+ size
;
242 if (!(md
->attribute
& EFI_MEMORY_RUNTIME
) &&
243 md
->type
!= EFI_BOOT_SERVICES_CODE
&&
244 md
->type
!= EFI_BOOT_SERVICES_DATA
)
248 if (phys_addr
>= md
->phys_addr
&& phys_addr
< end
) {
249 phys_addr
+= md
->virt_addr
- md
->phys_addr
;
250 return (__force
void __iomem
*)(unsigned long)phys_addr
;
256 static __initdata efi_config_table_type_t common_tables
[] = {
257 {ACPI_20_TABLE_GUID
, "ACPI 2.0", &efi
.acpi20
},
258 {ACPI_TABLE_GUID
, "ACPI", &efi
.acpi
},
259 {HCDP_TABLE_GUID
, "HCDP", &efi
.hcdp
},
260 {MPS_TABLE_GUID
, "MPS", &efi
.mps
},
261 {SAL_SYSTEM_TABLE_GUID
, "SALsystab", &efi
.sal_systab
},
262 {SMBIOS_TABLE_GUID
, "SMBIOS", &efi
.smbios
},
263 {UGA_IO_PROTOCOL_GUID
, "UGA", &efi
.uga
},
264 {NULL_GUID
, NULL
, NULL
},
267 static __init
int match_config_table(efi_guid_t
*guid
,
269 efi_config_table_type_t
*table_types
)
271 u8 str
[EFI_VARIABLE_GUID_LEN
+ 1];
275 efi_guid_to_str(guid
, str
);
277 for (i
= 0; efi_guidcmp(table_types
[i
].guid
, NULL_GUID
); i
++) {
278 efi_guid_to_str(&table_types
[i
].guid
, str
);
280 if (!efi_guidcmp(*guid
, table_types
[i
].guid
)) {
281 *(table_types
[i
].ptr
) = table
;
282 pr_cont(" %s=0x%lx ",
283 table_types
[i
].name
, table
);
292 int __init
efi_config_init(efi_config_table_type_t
*arch_tables
)
294 void *config_tables
, *tablep
;
297 if (efi_enabled(EFI_64BIT
))
298 sz
= sizeof(efi_config_table_64_t
);
300 sz
= sizeof(efi_config_table_32_t
);
303 * Let's see what config tables the firmware passed to us.
305 config_tables
= early_memremap(efi
.systab
->tables
,
306 efi
.systab
->nr_tables
* sz
);
307 if (config_tables
== NULL
) {
308 pr_err("Could not map Configuration table!\n");
312 tablep
= config_tables
;
314 for (i
= 0; i
< efi
.systab
->nr_tables
; i
++) {
318 if (efi_enabled(EFI_64BIT
)) {
320 guid
= ((efi_config_table_64_t
*)tablep
)->guid
;
321 table64
= ((efi_config_table_64_t
*)tablep
)->table
;
326 pr_err("Table located above 4GB, disabling EFI.\n");
327 early_memunmap(config_tables
,
328 efi
.systab
->nr_tables
* sz
);
333 guid
= ((efi_config_table_32_t
*)tablep
)->guid
;
334 table
= ((efi_config_table_32_t
*)tablep
)->table
;
337 if (!match_config_table(&guid
, table
, common_tables
))
338 match_config_table(&guid
, table
, arch_tables
);
343 early_memunmap(config_tables
, efi
.systab
->nr_tables
* sz
);
345 set_bit(EFI_CONFIG_TABLES
, &efi
.flags
);
350 #ifdef CONFIG_EFI_VARS_MODULE
351 static int __init
efi_load_efivars(void)
353 struct platform_device
*pdev
;
355 if (!efi_enabled(EFI_RUNTIME_SERVICES
))
358 pdev
= platform_device_register_simple("efivars", 0, NULL
, 0);
359 return IS_ERR(pdev
) ? PTR_ERR(pdev
) : 0;
361 device_initcall(efi_load_efivars
);
364 #ifdef CONFIG_EFI_PARAMS_FROM_FDT
366 #define UEFI_PARAM(name, prop, field) \
370 offsetof(struct efi_fdt_params, field), \
371 FIELD_SIZEOF(struct efi_fdt_params, field) \
374 static __initdata
struct {
376 const char propname
[32];
380 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table
),
381 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap
),
382 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size
),
383 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size
),
384 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver
)
393 static int __init
fdt_find_uefi_params(unsigned long node
, const char *uname
,
394 int depth
, void *data
)
396 struct param_info
*info
= data
;
403 (strcmp(uname
, "chosen") != 0 && strcmp(uname
, "chosen@0") != 0))
406 for (i
= 0; i
< ARRAY_SIZE(dt_params
); i
++) {
407 prop
= of_get_flat_dt_prop(node
, dt_params
[i
].propname
, &len
);
410 dest
= info
->params
+ dt_params
[i
].offset
;
413 val
= of_read_number(prop
, len
/ sizeof(u32
));
415 if (dt_params
[i
].size
== sizeof(u32
))
421 pr_info(" %s: 0x%0*llx\n", dt_params
[i
].name
,
422 dt_params
[i
].size
* 2, val
);
427 int __init
efi_get_fdt_params(struct efi_fdt_params
*params
, int verbose
)
429 struct param_info info
;
432 pr_info("Getting EFI parameters from FDT:\n");
434 info
.verbose
= verbose
;
436 info
.params
= params
;
438 ret
= of_scan_flat_dt(fdt_find_uefi_params
, &info
);
440 pr_info("UEFI not found.\n");
442 pr_err("Can't find '%s' in device tree!\n",
443 dt_params
[info
.found
].name
);
447 #endif /* CONFIG_EFI_PARAMS_FROM_FDT */
449 static __initdata
char memory_type_name
[][20] = {
457 "Conventional Memory",
459 "ACPI Reclaim Memory",
466 char * __init
efi_md_typeattr_format(char *buf
, size_t size
,
467 const efi_memory_desc_t
*md
)
474 if (md
->type
>= ARRAY_SIZE(memory_type_name
))
475 type_len
= snprintf(pos
, size
, "[type=%u", md
->type
);
477 type_len
= snprintf(pos
, size
, "[%-*s",
478 (int)(sizeof(memory_type_name
[0]) - 1),
479 memory_type_name
[md
->type
]);
480 if (type_len
>= size
)
486 attr
= md
->attribute
;
487 if (attr
& ~(EFI_MEMORY_UC
| EFI_MEMORY_WC
| EFI_MEMORY_WT
|
488 EFI_MEMORY_WB
| EFI_MEMORY_UCE
| EFI_MEMORY_WP
|
489 EFI_MEMORY_RP
| EFI_MEMORY_XP
| EFI_MEMORY_RUNTIME
))
490 snprintf(pos
, size
, "|attr=0x%016llx]",
491 (unsigned long long)attr
);
493 snprintf(pos
, size
, "|%3s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
494 attr
& EFI_MEMORY_RUNTIME
? "RUN" : "",
495 attr
& EFI_MEMORY_XP
? "XP" : "",
496 attr
& EFI_MEMORY_RP
? "RP" : "",
497 attr
& EFI_MEMORY_WP
? "WP" : "",
498 attr
& EFI_MEMORY_UCE
? "UCE" : "",
499 attr
& EFI_MEMORY_WB
? "WB" : "",
500 attr
& EFI_MEMORY_WT
? "WT" : "",
501 attr
& EFI_MEMORY_WC
? "WC" : "",
502 attr
& EFI_MEMORY_UC
? "UC" : "");