Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Extensible Firmware Interface
4 *
5 * Based on Extensible Firmware Interface Specification version 2.4
6 *
7 * Copyright (C) 2013, 2014 Linaro Ltd.
8 */
9
10#include <linux/dmi.h>
11#include <linux/efi.h>
12#include <linux/io.h>
13#include <linux/memblock.h>
14#include <linux/mm_types.h>
15#include <linux/preempt.h>
16#include <linux/rbtree.h>
17#include <linux/rwsem.h>
18#include <linux/sched.h>
19#include <linux/slab.h>
20#include <linux/spinlock.h>
21#include <linux/pgtable.h>
22
23#include <asm/cacheflush.h>
24#include <asm/efi.h>
25#include <asm/mmu.h>
26#include <asm/pgalloc.h>
27
28#if defined(CONFIG_PTDUMP_DEBUGFS) || defined(CONFIG_ARM_PTDUMP_DEBUGFS)
29#include <asm/ptdump.h>
30
31static struct ptdump_info efi_ptdump_info = {
32 .mm = &efi_mm,
33 .markers = (struct addr_marker[]){
34 { 0, "UEFI runtime start" },
35 { EFI_RUNTIME_MAP_END, "UEFI runtime end" },
36 { -1, NULL }
37 },
38 .base_addr = 0,
39};
40
41static int __init ptdump_init(void)
42{
43 if (efi_enabled(EFI_RUNTIME_SERVICES))
44 ptdump_debugfs_register(&efi_ptdump_info, "efi_page_tables");
45
46 return 0;
47}
48device_initcall(ptdump_init);
49
50#endif
51
52static bool __init efi_virtmap_init(void)
53{
54 efi_memory_desc_t *md;
55
56 efi_mm.pgd = pgd_alloc(&efi_mm);
57 mm_init_cpumask(&efi_mm);
58 init_new_context(NULL, &efi_mm);
59
60 for_each_efi_memory_desc(md) {
61 phys_addr_t phys = md->phys_addr;
62 int ret;
63
64 if (!(md->attribute & EFI_MEMORY_RUNTIME))
65 continue;
66 if (md->virt_addr == U64_MAX)
67 return false;
68
69 ret = efi_create_mapping(&efi_mm, md);
70 if (ret) {
71 pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
72 &phys, ret);
73 return false;
74 }
75 }
76
77 if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
78 return false;
79
80 return true;
81}
82
83/*
84 * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
85 * non-early mapping of the UEFI system table and virtual mappings for all
86 * EFI_MEMORY_RUNTIME regions.
87 */
88static int __init arm_enable_runtime_services(void)
89{
90 u64 mapsize;
91
92 if (!efi_enabled(EFI_BOOT)) {
93 pr_info("EFI services will not be available.\n");
94 return 0;
95 }
96
97 efi_memmap_unmap();
98
99 mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
100
101 if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
102 pr_err("Failed to remap EFI memory map\n");
103 return 0;
104 }
105
106 if (efi_soft_reserve_enabled()) {
107 efi_memory_desc_t *md;
108
109 for_each_efi_memory_desc(md) {
110 int md_size = md->num_pages << EFI_PAGE_SHIFT;
111 struct resource *res;
112
113 if (!(md->attribute & EFI_MEMORY_SP))
114 continue;
115
116 res = kzalloc(sizeof(*res), GFP_KERNEL);
117 if (WARN_ON(!res))
118 break;
119
120 res->start = md->phys_addr;
121 res->end = md->phys_addr + md_size - 1;
122 res->name = "Soft Reserved";
123 res->flags = IORESOURCE_MEM;
124 res->desc = IORES_DESC_SOFT_RESERVED;
125
126 insert_resource(&iomem_resource, res);
127 }
128 }
129
130 if (efi_runtime_disabled()) {
131 pr_info("EFI runtime services will be disabled.\n");
132 return 0;
133 }
134
135 if (efi_enabled(EFI_RUNTIME_SERVICES)) {
136 pr_info("EFI runtime services access via paravirt.\n");
137 return 0;
138 }
139
140 pr_info("Remapping and enabling EFI services.\n");
141
142 if (!efi_virtmap_init()) {
143 pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
144 return -ENOMEM;
145 }
146
147 /* Set up runtime services function pointers */
148 efi_native_runtime_setup();
149 set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
150
151 return 0;
152}
153early_initcall(arm_enable_runtime_services);
154
155void efi_virtmap_load(void)
156{
157 preempt_disable();
158 efi_set_pgd(&efi_mm);
159}
160
161void efi_virtmap_unload(void)
162{
163 efi_set_pgd(current->active_mm);
164 preempt_enable();
165}
166
167
168static int __init arm_dmi_init(void)
169{
170 /*
171 * On arm64/ARM, DMI depends on UEFI, and dmi_setup() needs to
172 * be called early because dmi_id_init(), which is an arch_initcall
173 * itself, depends on dmi_scan_machine() having been called already.
174 */
175 dmi_setup();
176 return 0;
177}
178core_initcall(arm_dmi_init);
1/*
2 * Extensible Firmware Interface
3 *
4 * Based on Extensible Firmware Interface Specification version 2.4
5 *
6 * Copyright (C) 2013, 2014 Linaro Ltd.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14#include <linux/dmi.h>
15#include <linux/efi.h>
16#include <linux/io.h>
17#include <linux/memblock.h>
18#include <linux/mm_types.h>
19#include <linux/preempt.h>
20#include <linux/rbtree.h>
21#include <linux/rwsem.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24#include <linux/spinlock.h>
25
26#include <asm/cacheflush.h>
27#include <asm/efi.h>
28#include <asm/mmu.h>
29#include <asm/pgalloc.h>
30#include <asm/pgtable.h>
31
32extern u64 efi_system_table;
33
34#ifdef CONFIG_ARM64_PTDUMP_DEBUGFS
35#include <asm/ptdump.h>
36
37static struct ptdump_info efi_ptdump_info = {
38 .mm = &efi_mm,
39 .markers = (struct addr_marker[]){
40 { 0, "UEFI runtime start" },
41 { TASK_SIZE_64, "UEFI runtime end" }
42 },
43 .base_addr = 0,
44};
45
46static int __init ptdump_init(void)
47{
48 if (!efi_enabled(EFI_RUNTIME_SERVICES))
49 return 0;
50
51 return ptdump_debugfs_register(&efi_ptdump_info, "efi_page_tables");
52}
53device_initcall(ptdump_init);
54
55#endif
56
57static bool __init efi_virtmap_init(void)
58{
59 efi_memory_desc_t *md;
60 bool systab_found;
61
62 efi_mm.pgd = pgd_alloc(&efi_mm);
63 mm_init_cpumask(&efi_mm);
64 init_new_context(NULL, &efi_mm);
65
66 systab_found = false;
67 for_each_efi_memory_desc(md) {
68 phys_addr_t phys = md->phys_addr;
69 int ret;
70
71 if (!(md->attribute & EFI_MEMORY_RUNTIME))
72 continue;
73 if (md->virt_addr == 0)
74 return false;
75
76 ret = efi_create_mapping(&efi_mm, md);
77 if (ret) {
78 pr_warn(" EFI remap %pa: failed to create mapping (%d)\n",
79 &phys, ret);
80 return false;
81 }
82 /*
83 * If this entry covers the address of the UEFI system table,
84 * calculate and record its virtual address.
85 */
86 if (efi_system_table >= phys &&
87 efi_system_table < phys + (md->num_pages * EFI_PAGE_SIZE)) {
88 efi.systab = (void *)(unsigned long)(efi_system_table -
89 phys + md->virt_addr);
90 systab_found = true;
91 }
92 }
93 if (!systab_found) {
94 pr_err("No virtual mapping found for the UEFI System Table\n");
95 return false;
96 }
97
98 if (efi_memattr_apply_permissions(&efi_mm, efi_set_mapping_permissions))
99 return false;
100
101 return true;
102}
103
104/*
105 * Enable the UEFI Runtime Services if all prerequisites are in place, i.e.,
106 * non-early mapping of the UEFI system table and virtual mappings for all
107 * EFI_MEMORY_RUNTIME regions.
108 */
109static int __init arm_enable_runtime_services(void)
110{
111 u64 mapsize;
112
113 if (!efi_enabled(EFI_BOOT)) {
114 pr_info("EFI services will not be available.\n");
115 return 0;
116 }
117
118 if (efi_runtime_disabled()) {
119 pr_info("EFI runtime services will be disabled.\n");
120 return 0;
121 }
122
123 if (efi_enabled(EFI_RUNTIME_SERVICES)) {
124 pr_info("EFI runtime services access via paravirt.\n");
125 return 0;
126 }
127
128 pr_info("Remapping and enabling EFI services.\n");
129
130 mapsize = efi.memmap.desc_size * efi.memmap.nr_map;
131
132 if (efi_memmap_init_late(efi.memmap.phys_map, mapsize)) {
133 pr_err("Failed to remap EFI memory map\n");
134 return -ENOMEM;
135 }
136
137 if (!efi_virtmap_init()) {
138 pr_err("UEFI virtual mapping missing or invalid -- runtime services will not be available\n");
139 return -ENOMEM;
140 }
141
142 /* Set up runtime services function pointers */
143 efi_native_runtime_setup();
144 set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
145
146 return 0;
147}
148early_initcall(arm_enable_runtime_services);
149
150void efi_virtmap_load(void)
151{
152 preempt_disable();
153 efi_set_pgd(&efi_mm);
154}
155
156void efi_virtmap_unload(void)
157{
158 efi_set_pgd(current->active_mm);
159 preempt_enable();
160}
161
162
163static int __init arm_dmi_init(void)
164{
165 /*
166 * On arm64/ARM, DMI depends on UEFI, and dmi_scan_machine() needs to
167 * be called early because dmi_id_init(), which is an arch_initcall
168 * itself, depends on dmi_scan_machine() having been called already.
169 */
170 dmi_scan_machine();
171 if (dmi_available)
172 dmi_set_dump_stack_arch_desc();
173 return 0;
174}
175core_initcall(arm_dmi_init);