1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #define BOOT_CTYPE_H |
3 | #include "misc.h" |
4 | #include "error.h" |
5 | #include "../string.h" |
6 | #include "efi.h" |
7 | |
8 | #include <linux/numa.h> |
9 | |
10 | /* |
11 | * Longest parameter of 'acpi=' is 'copy_dsdt', plus an extra '\0' |
12 | * for termination. |
13 | */ |
14 | #define MAX_ACPI_ARG_LENGTH 10 |
15 | |
16 | /* |
17 | * Immovable memory regions representation. Max amount of memory regions is |
18 | * MAX_NUMNODES*2. |
19 | */ |
20 | struct mem_vector immovable_mem[MAX_NUMNODES*2]; |
21 | |
22 | static acpi_physical_address |
23 | __efi_get_rsdp_addr(unsigned long cfg_tbl_pa, unsigned int cfg_tbl_len) |
24 | { |
25 | #ifdef CONFIG_EFI |
26 | unsigned long rsdp_addr; |
27 | int ret; |
28 | |
29 | /* |
30 | * Search EFI system tables for RSDP. Preferred is ACPI_20_TABLE_GUID to |
31 | * ACPI_TABLE_GUID because it has more features. |
32 | */ |
33 | rsdp_addr = efi_find_vendor_table(bp: boot_params_ptr, cfg_tbl_pa, cfg_tbl_len, |
34 | ACPI_20_TABLE_GUID); |
35 | if (rsdp_addr) |
36 | return (acpi_physical_address)rsdp_addr; |
37 | |
38 | /* No ACPI_20_TABLE_GUID found, fallback to ACPI_TABLE_GUID. */ |
39 | rsdp_addr = efi_find_vendor_table(bp: boot_params_ptr, cfg_tbl_pa, cfg_tbl_len, |
40 | ACPI_TABLE_GUID); |
41 | if (rsdp_addr) |
42 | return (acpi_physical_address)rsdp_addr; |
43 | |
44 | debug_putstr("Error getting RSDP address.\n" ); |
45 | #endif |
46 | return 0; |
47 | } |
48 | |
49 | static acpi_physical_address efi_get_rsdp_addr(void) |
50 | { |
51 | #ifdef CONFIG_EFI |
52 | unsigned long cfg_tbl_pa = 0; |
53 | unsigned int cfg_tbl_len; |
54 | unsigned long systab_pa; |
55 | unsigned int nr_tables; |
56 | enum efi_type et; |
57 | int ret; |
58 | |
59 | et = efi_get_type(bp: boot_params_ptr); |
60 | if (et == EFI_TYPE_NONE) |
61 | return 0; |
62 | |
63 | systab_pa = efi_get_system_table(bp: boot_params_ptr); |
64 | if (!systab_pa) |
65 | error(m: "EFI support advertised, but unable to locate system table." ); |
66 | |
67 | ret = efi_get_conf_table(bp: boot_params_ptr, cfg_tbl_pa: &cfg_tbl_pa, cfg_tbl_len: &cfg_tbl_len); |
68 | if (ret || !cfg_tbl_pa) |
69 | error(m: "EFI config table not found." ); |
70 | |
71 | return __efi_get_rsdp_addr(cfg_tbl_pa, cfg_tbl_len); |
72 | #else |
73 | return 0; |
74 | #endif |
75 | } |
76 | |
77 | static u8 compute_checksum(u8 *buffer, u32 length) |
78 | { |
79 | u8 *end = buffer + length; |
80 | u8 sum = 0; |
81 | |
82 | while (buffer < end) |
83 | sum += *(buffer++); |
84 | |
85 | return sum; |
86 | } |
87 | |
88 | /* Search a block of memory for the RSDP signature. */ |
89 | static u8 *scan_mem_for_rsdp(u8 *start, u32 length) |
90 | { |
91 | struct acpi_table_rsdp *rsdp; |
92 | u8 *address, *end; |
93 | |
94 | end = start + length; |
95 | |
96 | /* Search from given start address for the requested length */ |
97 | for (address = start; address < end; address += ACPI_RSDP_SCAN_STEP) { |
98 | /* |
99 | * Both RSDP signature and checksum must be correct. |
100 | * Note: Sometimes there exists more than one RSDP in memory; |
101 | * the valid RSDP has a valid checksum, all others have an |
102 | * invalid checksum. |
103 | */ |
104 | rsdp = (struct acpi_table_rsdp *)address; |
105 | |
106 | /* BAD Signature */ |
107 | if (!ACPI_VALIDATE_RSDP_SIG(rsdp->signature)) |
108 | continue; |
109 | |
110 | /* Check the standard checksum */ |
111 | if (compute_checksum(buffer: (u8 *)rsdp, ACPI_RSDP_CHECKSUM_LENGTH)) |
112 | continue; |
113 | |
114 | /* Check extended checksum if table version >= 2 */ |
115 | if ((rsdp->revision >= 2) && |
116 | (compute_checksum(buffer: (u8 *)rsdp, ACPI_RSDP_XCHECKSUM_LENGTH))) |
117 | continue; |
118 | |
119 | /* Signature and checksum valid, we have found a real RSDP */ |
120 | return address; |
121 | } |
122 | return NULL; |
123 | } |
124 | |
125 | /* Search RSDP address in EBDA. */ |
126 | static acpi_physical_address bios_get_rsdp_addr(void) |
127 | { |
128 | unsigned long address; |
129 | u8 *rsdp; |
130 | |
131 | /* Get the location of the Extended BIOS Data Area (EBDA) */ |
132 | address = *(u16 *)ACPI_EBDA_PTR_LOCATION; |
133 | address <<= 4; |
134 | |
135 | /* |
136 | * Search EBDA paragraphs (EBDA is required to be a minimum of |
137 | * 1K length) |
138 | */ |
139 | if (address > 0x400) { |
140 | rsdp = scan_mem_for_rsdp(start: (u8 *)address, ACPI_EBDA_WINDOW_SIZE); |
141 | if (rsdp) |
142 | return (acpi_physical_address)(unsigned long)rsdp; |
143 | } |
144 | |
145 | /* Search upper memory: 16-byte boundaries in E0000h-FFFFFh */ |
146 | rsdp = scan_mem_for_rsdp(start: (u8 *) ACPI_HI_RSDP_WINDOW_BASE, |
147 | ACPI_HI_RSDP_WINDOW_SIZE); |
148 | if (rsdp) |
149 | return (acpi_physical_address)(unsigned long)rsdp; |
150 | |
151 | return 0; |
152 | } |
153 | |
154 | /* Return RSDP address on success, otherwise 0. */ |
155 | acpi_physical_address get_rsdp_addr(void) |
156 | { |
157 | acpi_physical_address pa; |
158 | |
159 | pa = boot_params_ptr->acpi_rsdp_addr; |
160 | |
161 | if (!pa) |
162 | pa = efi_get_rsdp_addr(); |
163 | |
164 | if (!pa) |
165 | pa = bios_get_rsdp_addr(); |
166 | |
167 | return pa; |
168 | } |
169 | |
170 | #if defined(CONFIG_RANDOMIZE_BASE) && defined(CONFIG_MEMORY_HOTREMOVE) |
171 | /* |
172 | * Max length of 64-bit hex address string is 19, prefix "0x" + 16 hex |
173 | * digits, and '\0' for termination. |
174 | */ |
175 | #define MAX_ADDR_LEN 19 |
176 | |
177 | static unsigned long get_cmdline_acpi_rsdp(void) |
178 | { |
179 | unsigned long addr = 0; |
180 | |
181 | #ifdef CONFIG_KEXEC |
182 | char val[MAX_ADDR_LEN] = { }; |
183 | int ret; |
184 | |
185 | ret = cmdline_find_option(option: "acpi_rsdp" , buffer: val, MAX_ADDR_LEN); |
186 | if (ret < 0) |
187 | return 0; |
188 | |
189 | if (boot_kstrtoul(s: val, base: 16, res: &addr)) |
190 | return 0; |
191 | #endif |
192 | return addr; |
193 | } |
194 | |
195 | /* Compute SRAT address from RSDP. */ |
196 | static unsigned long get_acpi_srat_table(void) |
197 | { |
198 | unsigned long root_table, acpi_table; |
199 | struct acpi_table_header *; |
200 | struct acpi_table_rsdp *rsdp; |
201 | u32 num_entries, size, len; |
202 | char arg[10]; |
203 | u8 *entry; |
204 | |
205 | /* |
206 | * Check whether we were given an RSDP on the command line. We don't |
207 | * stash this in boot params because the kernel itself may have |
208 | * different ideas about whether to trust a command-line parameter. |
209 | */ |
210 | rsdp = (struct acpi_table_rsdp *)get_cmdline_acpi_rsdp(); |
211 | if (!rsdp) |
212 | rsdp = (struct acpi_table_rsdp *)(long) |
213 | boot_params_ptr->acpi_rsdp_addr; |
214 | |
215 | if (!rsdp) |
216 | return 0; |
217 | |
218 | /* Get ACPI root table from RSDP.*/ |
219 | if (!(cmdline_find_option(option: "acpi" , buffer: arg, bufsize: sizeof(arg)) == 4 && |
220 | !strncmp(cs: arg, ct: "rsdt" , count: 4)) && |
221 | rsdp->xsdt_physical_address && |
222 | rsdp->revision > 1) { |
223 | root_table = rsdp->xsdt_physical_address; |
224 | size = ACPI_XSDT_ENTRY_SIZE; |
225 | } else { |
226 | root_table = rsdp->rsdt_physical_address; |
227 | size = ACPI_RSDT_ENTRY_SIZE; |
228 | } |
229 | |
230 | if (!root_table) |
231 | return 0; |
232 | |
233 | header = (struct acpi_table_header *)root_table; |
234 | len = header->length; |
235 | if (len < sizeof(struct acpi_table_header) + size) |
236 | return 0; |
237 | |
238 | num_entries = (len - sizeof(struct acpi_table_header)) / size; |
239 | entry = (u8 *)(root_table + sizeof(struct acpi_table_header)); |
240 | |
241 | while (num_entries--) { |
242 | if (size == ACPI_RSDT_ENTRY_SIZE) |
243 | acpi_table = *(u32 *)entry; |
244 | else |
245 | acpi_table = *(u64 *)entry; |
246 | |
247 | if (acpi_table) { |
248 | header = (struct acpi_table_header *)acpi_table; |
249 | |
250 | if (ACPI_COMPARE_NAMESEG(header->signature, ACPI_SIG_SRAT)) |
251 | return acpi_table; |
252 | } |
253 | entry += size; |
254 | } |
255 | return 0; |
256 | } |
257 | |
258 | /** |
259 | * count_immovable_mem_regions - Parse SRAT and cache the immovable |
260 | * memory regions into the immovable_mem array. |
261 | * |
262 | * Return the number of immovable memory regions on success, 0 on failure: |
263 | * |
264 | * - Too many immovable memory regions |
265 | * - ACPI off or no SRAT found |
266 | * - No immovable memory region found. |
267 | */ |
268 | int count_immovable_mem_regions(void) |
269 | { |
270 | unsigned long table_addr, table_end, table; |
271 | struct acpi_subtable_header *sub_table; |
272 | struct acpi_table_header *; |
273 | char arg[MAX_ACPI_ARG_LENGTH]; |
274 | int num = 0; |
275 | |
276 | if (cmdline_find_option(option: "acpi" , buffer: arg, bufsize: sizeof(arg)) == 3 && |
277 | !strncmp(cs: arg, ct: "off" , count: 3)) |
278 | return 0; |
279 | |
280 | table_addr = get_acpi_srat_table(); |
281 | if (!table_addr) |
282 | return 0; |
283 | |
284 | table_header = (struct acpi_table_header *)table_addr; |
285 | table_end = table_addr + table_header->length; |
286 | table = table_addr + sizeof(struct acpi_table_srat); |
287 | |
288 | while (table + sizeof(struct acpi_subtable_header) < table_end) { |
289 | |
290 | sub_table = (struct acpi_subtable_header *)table; |
291 | if (!sub_table->length) { |
292 | debug_putstr("Invalid zero length SRAT subtable.\n" ); |
293 | return 0; |
294 | } |
295 | |
296 | if (sub_table->type == ACPI_SRAT_TYPE_MEMORY_AFFINITY) { |
297 | struct acpi_srat_mem_affinity *ma; |
298 | |
299 | ma = (struct acpi_srat_mem_affinity *)sub_table; |
300 | if (!(ma->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE) && ma->length) { |
301 | immovable_mem[num].start = ma->base_address; |
302 | immovable_mem[num].size = ma->length; |
303 | num++; |
304 | } |
305 | |
306 | if (num >= MAX_NUMNODES*2) { |
307 | debug_putstr("Too many immovable memory regions, aborting.\n" ); |
308 | return 0; |
309 | } |
310 | } |
311 | table += sub_table->length; |
312 | } |
313 | return num; |
314 | } |
315 | #endif /* CONFIG_RANDOMIZE_BASE && CONFIG_MEMORY_HOTREMOVE */ |
316 | |