xref: /openbmc/linux/drivers/acpi/processor_core.c (revision 2a598d0b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2005 Intel Corporation
4  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
5  *
6  *	Alex Chiang <achiang@hp.com>
7  *	- Unified x86/ia64 implementations
8  *
9  * I/O APIC hotplug support
10  *	Yinghai Lu <yinghai@kernel.org>
11  *	Jiang Liu <jiang.liu@intel.com>
12  */
13 #include <linux/export.h>
14 #include <linux/acpi.h>
15 #include <acpi/processor.h>
16 
17 static struct acpi_table_madt *get_madt_table(void)
18 {
19 	static struct acpi_table_madt *madt;
20 	static int read_madt;
21 
22 	if (!read_madt) {
23 		if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
24 					(struct acpi_table_header **)&madt)))
25 			madt = NULL;
26 		read_madt++;
27 	}
28 
29 	return madt;
30 }
31 
32 static int map_lapic_id(struct acpi_subtable_header *entry,
33 		 u32 acpi_id, phys_cpuid_t *apic_id)
34 {
35 	struct acpi_madt_local_apic *lapic =
36 		container_of(entry, struct acpi_madt_local_apic, header);
37 
38 	if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
39 		return -ENODEV;
40 
41 	if (lapic->processor_id != acpi_id)
42 		return -EINVAL;
43 
44 	*apic_id = lapic->id;
45 	return 0;
46 }
47 
48 static int map_x2apic_id(struct acpi_subtable_header *entry,
49 		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
50 {
51 	struct acpi_madt_local_x2apic *apic =
52 		container_of(entry, struct acpi_madt_local_x2apic, header);
53 
54 	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
55 		return -ENODEV;
56 
57 	if (device_declaration && (apic->uid == acpi_id)) {
58 		*apic_id = apic->local_apic_id;
59 		return 0;
60 	}
61 
62 	return -EINVAL;
63 }
64 
65 static int map_lsapic_id(struct acpi_subtable_header *entry,
66 		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
67 {
68 	struct acpi_madt_local_sapic *lsapic =
69 		container_of(entry, struct acpi_madt_local_sapic, header);
70 
71 	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
72 		return -ENODEV;
73 
74 	if (device_declaration) {
75 		if ((entry->length < 16) || (lsapic->uid != acpi_id))
76 			return -EINVAL;
77 	} else if (lsapic->processor_id != acpi_id)
78 		return -EINVAL;
79 
80 	*apic_id = (lsapic->id << 8) | lsapic->eid;
81 	return 0;
82 }
83 
84 /*
85  * Retrieve the ARM CPU physical identifier (MPIDR)
86  */
87 static int map_gicc_mpidr(struct acpi_subtable_header *entry,
88 		int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
89 {
90 	struct acpi_madt_generic_interrupt *gicc =
91 	    container_of(entry, struct acpi_madt_generic_interrupt, header);
92 
93 	if (!(gicc->flags & ACPI_MADT_ENABLED))
94 		return -ENODEV;
95 
96 	/* device_declaration means Device object in DSDT, in the
97 	 * GIC interrupt model, logical processors are required to
98 	 * have a Processor Device object in the DSDT, so we should
99 	 * check device_declaration here
100 	 */
101 	if (device_declaration && (gicc->uid == acpi_id)) {
102 		*mpidr = gicc->arm_mpidr;
103 		return 0;
104 	}
105 
106 	return -EINVAL;
107 }
108 
109 /*
110  * Retrieve the RISC-V hartid for the processor
111  */
112 static int map_rintc_hartid(struct acpi_subtable_header *entry,
113 			    int device_declaration, u32 acpi_id,
114 			    phys_cpuid_t *hartid)
115 {
116 	struct acpi_madt_rintc *rintc =
117 	    container_of(entry, struct acpi_madt_rintc, header);
118 
119 	if (!(rintc->flags & ACPI_MADT_ENABLED))
120 		return -ENODEV;
121 
122 	/* device_declaration means Device object in DSDT, in the
123 	 * RISC-V, logical processors are required to
124 	 * have a Processor Device object in the DSDT, so we should
125 	 * check device_declaration here
126 	 */
127 	if (device_declaration && rintc->uid == acpi_id) {
128 		*hartid = rintc->hart_id;
129 		return 0;
130 	}
131 
132 	return -EINVAL;
133 }
134 
135 static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
136 				   int type, u32 acpi_id)
137 {
138 	unsigned long madt_end, entry;
139 	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;	/* CPU hardware ID */
140 
141 	if (!madt)
142 		return phys_id;
143 
144 	entry = (unsigned long)madt;
145 	madt_end = entry + madt->header.length;
146 
147 	/* Parse all entries looking for a match. */
148 
149 	entry += sizeof(struct acpi_table_madt);
150 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
151 		struct acpi_subtable_header *header =
152 			(struct acpi_subtable_header *)entry;
153 		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
154 			if (!map_lapic_id(header, acpi_id, &phys_id))
155 				break;
156 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
157 			if (!map_x2apic_id(header, type, acpi_id, &phys_id))
158 				break;
159 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
160 			if (!map_lsapic_id(header, type, acpi_id, &phys_id))
161 				break;
162 		} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
163 			if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
164 				break;
165 		} else if (header->type == ACPI_MADT_TYPE_RINTC) {
166 			if (!map_rintc_hartid(header, type, acpi_id, &phys_id))
167 				break;
168 		}
169 		entry += header->length;
170 	}
171 	return phys_id;
172 }
173 
174 phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
175 {
176 	struct acpi_table_madt *madt = NULL;
177 	phys_cpuid_t rv;
178 
179 	acpi_get_table(ACPI_SIG_MADT, 0,
180 		       (struct acpi_table_header **)&madt);
181 	if (!madt)
182 		return PHYS_CPUID_INVALID;
183 
184 	rv = map_madt_entry(madt, 1, acpi_id);
185 
186 	acpi_put_table((struct acpi_table_header *)madt);
187 
188 	return rv;
189 }
190 
191 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
192 {
193 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
194 	union acpi_object *obj;
195 	struct acpi_subtable_header *header;
196 	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
197 
198 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
199 		goto exit;
200 
201 	if (!buffer.length || !buffer.pointer)
202 		goto exit;
203 
204 	obj = buffer.pointer;
205 	if (obj->type != ACPI_TYPE_BUFFER ||
206 	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
207 		goto exit;
208 	}
209 
210 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
211 	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
212 		map_lapic_id(header, acpi_id, &phys_id);
213 	else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
214 		map_lsapic_id(header, type, acpi_id, &phys_id);
215 	else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
216 		map_x2apic_id(header, type, acpi_id, &phys_id);
217 	else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
218 		map_gicc_mpidr(header, type, acpi_id, &phys_id);
219 
220 exit:
221 	kfree(buffer.pointer);
222 	return phys_id;
223 }
224 
225 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
226 {
227 	phys_cpuid_t phys_id;
228 
229 	phys_id = map_mat_entry(handle, type, acpi_id);
230 	if (invalid_phys_cpuid(phys_id))
231 		phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
232 
233 	return phys_id;
234 }
235 EXPORT_SYMBOL_GPL(acpi_get_phys_id);
236 
237 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
238 {
239 #ifdef CONFIG_SMP
240 	int i;
241 #endif
242 
243 	if (invalid_phys_cpuid(phys_id)) {
244 		/*
245 		 * On UP processor, there is no _MAT or MADT table.
246 		 * So above phys_id is always set to PHYS_CPUID_INVALID.
247 		 *
248 		 * BIOS may define multiple CPU handles even for UP processor.
249 		 * For example,
250 		 *
251 		 * Scope (_PR)
252 		 * {
253 		 *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
254 		 *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
255 		 *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
256 		 *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
257 		 * }
258 		 *
259 		 * Ignores phys_id and always returns 0 for the processor
260 		 * handle with acpi id 0 if nr_cpu_ids is 1.
261 		 * This should be the case if SMP tables are not found.
262 		 * Return -EINVAL for other CPU's handle.
263 		 */
264 		if (nr_cpu_ids <= 1 && acpi_id == 0)
265 			return acpi_id;
266 		else
267 			return -EINVAL;
268 	}
269 
270 #ifdef CONFIG_SMP
271 	for_each_possible_cpu(i) {
272 		if (cpu_physical_id(i) == phys_id)
273 			return i;
274 	}
275 #else
276 	/* In UP kernel, only processor 0 is valid */
277 	if (phys_id == 0)
278 		return phys_id;
279 #endif
280 	return -ENODEV;
281 }
282 
283 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
284 {
285 	phys_cpuid_t phys_id;
286 
287 	phys_id = acpi_get_phys_id(handle, type, acpi_id);
288 
289 	return acpi_map_cpuid(phys_id, acpi_id);
290 }
291 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
292 
293 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
294 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
295 			 u64 *phys_addr, int *ioapic_id)
296 {
297 	struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
298 
299 	if (ioapic->global_irq_base != gsi_base)
300 		return 0;
301 
302 	*phys_addr = ioapic->address;
303 	*ioapic_id = ioapic->id;
304 	return 1;
305 }
306 
307 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
308 {
309 	struct acpi_subtable_header *hdr;
310 	unsigned long madt_end, entry;
311 	struct acpi_table_madt *madt;
312 	int apic_id = -1;
313 
314 	madt = get_madt_table();
315 	if (!madt)
316 		return apic_id;
317 
318 	entry = (unsigned long)madt;
319 	madt_end = entry + madt->header.length;
320 
321 	/* Parse all entries looking for a match. */
322 	entry += sizeof(struct acpi_table_madt);
323 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
324 		hdr = (struct acpi_subtable_header *)entry;
325 		if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
326 		    get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
327 			break;
328 		else
329 			entry += hdr->length;
330 	}
331 
332 	return apic_id;
333 }
334 
335 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
336 				  u64 *phys_addr)
337 {
338 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
339 	struct acpi_subtable_header *header;
340 	union acpi_object *obj;
341 	int apic_id = -1;
342 
343 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
344 		goto exit;
345 
346 	if (!buffer.length || !buffer.pointer)
347 		goto exit;
348 
349 	obj = buffer.pointer;
350 	if (obj->type != ACPI_TYPE_BUFFER ||
351 	    obj->buffer.length < sizeof(struct acpi_subtable_header))
352 		goto exit;
353 
354 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
355 	if (header->type == ACPI_MADT_TYPE_IO_APIC)
356 		get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
357 
358 exit:
359 	kfree(buffer.pointer);
360 	return apic_id;
361 }
362 
363 /**
364  * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
365  * @handle:	ACPI object for IOAPIC device
366  * @gsi_base:	GSI base to match with
367  * @phys_addr:	Pointer to store physical address of matching IOAPIC record
368  *
369  * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
370  * for an ACPI IOAPIC record matching @gsi_base.
371  * Return IOAPIC id and store physical address in @phys_addr if found a match,
372  * otherwise return <0.
373  */
374 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
375 {
376 	int apic_id;
377 
378 	apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
379 	if (apic_id == -1)
380 		apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
381 
382 	return apic_id;
383 }
384 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */
385