xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision 35267cea)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Shared support code for AMD K8 northbridges and derivatives.
4  * Copyright 2006 Andi Kleen, SUSE Labs.
5  */
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 
9 #include <linux/types.h>
10 #include <linux/slab.h>
11 #include <linux/init.h>
12 #include <linux/errno.h>
13 #include <linux/export.h>
14 #include <linux/spinlock.h>
15 #include <linux/pci_ids.h>
16 #include <asm/amd_nb.h>
17 
18 #define PCI_DEVICE_ID_AMD_17H_ROOT	0x1450
19 #define PCI_DEVICE_ID_AMD_17H_M10H_ROOT	0x15d0
20 #define PCI_DEVICE_ID_AMD_17H_M30H_ROOT	0x1480
21 #define PCI_DEVICE_ID_AMD_17H_M60H_ROOT	0x1630
22 #define PCI_DEVICE_ID_AMD_17H_DF_F4	0x1464
23 #define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
24 #define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
25 #define PCI_DEVICE_ID_AMD_17H_M60H_DF_F4 0x144c
26 #define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4 0x1444
27 #define PCI_DEVICE_ID_AMD_19H_DF_F4	0x1654
28 #define PCI_DEVICE_ID_AMD_19H_M50H_DF_F4 0x166e
29 
30 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
31 static DEFINE_MUTEX(smn_mutex);
32 
33 static u32 *flush_words;
34 
35 static const struct pci_device_id amd_root_ids[] = {
36 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
37 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
38 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
39 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_ROOT) },
40 	{}
41 };
42 
43 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
44 
45 static const struct pci_device_id amd_nb_misc_ids[] = {
46 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
47 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
48 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
49 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
50 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
51 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
52 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
53 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
54 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
55 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
56 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
57 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F3) },
58 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
59 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
60 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
61 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F3) },
62 	{}
63 };
64 
65 static const struct pci_device_id amd_nb_link_ids[] = {
66 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
67 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
68 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
69 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
70 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
71 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
72 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
73 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
74 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
75 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
76 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
77 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
78 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
79 	{}
80 };
81 
82 static const struct pci_device_id hygon_root_ids[] = {
83 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
84 	{}
85 };
86 
87 static const struct pci_device_id hygon_nb_misc_ids[] = {
88 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
89 	{}
90 };
91 
92 static const struct pci_device_id hygon_nb_link_ids[] = {
93 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
94 	{}
95 };
96 
97 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
98 	{ 0x00, 0x18, 0x20 },
99 	{ 0xff, 0x00, 0x20 },
100 	{ 0xfe, 0x00, 0x20 },
101 	{ }
102 };
103 
104 static struct amd_northbridge_info amd_northbridges;
105 
106 u16 amd_nb_num(void)
107 {
108 	return amd_northbridges.num;
109 }
110 EXPORT_SYMBOL_GPL(amd_nb_num);
111 
112 bool amd_nb_has_feature(unsigned int feature)
113 {
114 	return ((amd_northbridges.flags & feature) == feature);
115 }
116 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
117 
118 struct amd_northbridge *node_to_amd_nb(int node)
119 {
120 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
121 }
122 EXPORT_SYMBOL_GPL(node_to_amd_nb);
123 
124 static struct pci_dev *next_northbridge(struct pci_dev *dev,
125 					const struct pci_device_id *ids)
126 {
127 	do {
128 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
129 		if (!dev)
130 			break;
131 	} while (!pci_match_id(ids, dev));
132 	return dev;
133 }
134 
135 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
136 {
137 	struct pci_dev *root;
138 	int err = -ENODEV;
139 
140 	if (node >= amd_northbridges.num)
141 		goto out;
142 
143 	root = node_to_amd_nb(node)->root;
144 	if (!root)
145 		goto out;
146 
147 	mutex_lock(&smn_mutex);
148 
149 	err = pci_write_config_dword(root, 0x60, address);
150 	if (err) {
151 		pr_warn("Error programming SMN address 0x%x.\n", address);
152 		goto out_unlock;
153 	}
154 
155 	err = (write ? pci_write_config_dword(root, 0x64, *value)
156 		     : pci_read_config_dword(root, 0x64, value));
157 	if (err)
158 		pr_warn("Error %s SMN address 0x%x.\n",
159 			(write ? "writing to" : "reading from"), address);
160 
161 out_unlock:
162 	mutex_unlock(&smn_mutex);
163 
164 out:
165 	return err;
166 }
167 
168 int amd_smn_read(u16 node, u32 address, u32 *value)
169 {
170 	return __amd_smn_rw(node, address, value, false);
171 }
172 EXPORT_SYMBOL_GPL(amd_smn_read);
173 
174 int amd_smn_write(u16 node, u32 address, u32 value)
175 {
176 	return __amd_smn_rw(node, address, &value, true);
177 }
178 EXPORT_SYMBOL_GPL(amd_smn_write);
179 
180 /*
181  * Data Fabric Indirect Access uses FICAA/FICAD.
182  *
183  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
184  * on the device's Instance Id and the PCI function and register offset of
185  * the desired register.
186  *
187  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
188  * and FICAD HI registers but so far we only need the LO register.
189  */
190 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
191 {
192 	struct pci_dev *F4;
193 	u32 ficaa;
194 	int err = -ENODEV;
195 
196 	if (node >= amd_northbridges.num)
197 		goto out;
198 
199 	F4 = node_to_amd_nb(node)->link;
200 	if (!F4)
201 		goto out;
202 
203 	ficaa  = 1;
204 	ficaa |= reg & 0x3FC;
205 	ficaa |= (func & 0x7) << 11;
206 	ficaa |= instance_id << 16;
207 
208 	mutex_lock(&smn_mutex);
209 
210 	err = pci_write_config_dword(F4, 0x5C, ficaa);
211 	if (err) {
212 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
213 		goto out_unlock;
214 	}
215 
216 	err = pci_read_config_dword(F4, 0x98, lo);
217 	if (err)
218 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
219 
220 out_unlock:
221 	mutex_unlock(&smn_mutex);
222 
223 out:
224 	return err;
225 }
226 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
227 
228 int amd_cache_northbridges(void)
229 {
230 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
231 	const struct pci_device_id *link_ids = amd_nb_link_ids;
232 	const struct pci_device_id *root_ids = amd_root_ids;
233 	struct pci_dev *root, *misc, *link;
234 	struct amd_northbridge *nb;
235 	u16 roots_per_misc = 0;
236 	u16 misc_count = 0;
237 	u16 root_count = 0;
238 	u16 i, j;
239 
240 	if (amd_northbridges.num)
241 		return 0;
242 
243 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
244 		root_ids = hygon_root_ids;
245 		misc_ids = hygon_nb_misc_ids;
246 		link_ids = hygon_nb_link_ids;
247 	}
248 
249 	misc = NULL;
250 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
251 		misc_count++;
252 
253 	if (!misc_count)
254 		return -ENODEV;
255 
256 	root = NULL;
257 	while ((root = next_northbridge(root, root_ids)) != NULL)
258 		root_count++;
259 
260 	if (root_count) {
261 		roots_per_misc = root_count / misc_count;
262 
263 		/*
264 		 * There should be _exactly_ N roots for each DF/SMN
265 		 * interface.
266 		 */
267 		if (!roots_per_misc || (root_count % roots_per_misc)) {
268 			pr_info("Unsupported AMD DF/PCI configuration found\n");
269 			return -ENODEV;
270 		}
271 	}
272 
273 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
274 	if (!nb)
275 		return -ENOMEM;
276 
277 	amd_northbridges.nb = nb;
278 	amd_northbridges.num = misc_count;
279 
280 	link = misc = root = NULL;
281 	for (i = 0; i < amd_northbridges.num; i++) {
282 		node_to_amd_nb(i)->root = root =
283 			next_northbridge(root, root_ids);
284 		node_to_amd_nb(i)->misc = misc =
285 			next_northbridge(misc, misc_ids);
286 		node_to_amd_nb(i)->link = link =
287 			next_northbridge(link, link_ids);
288 
289 		/*
290 		 * If there are more PCI root devices than data fabric/
291 		 * system management network interfaces, then the (N)
292 		 * PCI roots per DF/SMN interface are functionally the
293 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
294 		 * PCI roots should be skipped per DF/SMN interface so
295 		 * the following DF/SMN interfaces get mapped to
296 		 * correct PCI roots.
297 		 */
298 		for (j = 1; j < roots_per_misc; j++)
299 			root = next_northbridge(root, root_ids);
300 	}
301 
302 	if (amd_gart_present())
303 		amd_northbridges.flags |= AMD_NB_GART;
304 
305 	/*
306 	 * Check for L3 cache presence.
307 	 */
308 	if (!cpuid_edx(0x80000006))
309 		return 0;
310 
311 	/*
312 	 * Some CPU families support L3 Cache Index Disable. There are some
313 	 * limitations because of E382 and E388 on family 0x10.
314 	 */
315 	if (boot_cpu_data.x86 == 0x10 &&
316 	    boot_cpu_data.x86_model >= 0x8 &&
317 	    (boot_cpu_data.x86_model > 0x9 ||
318 	     boot_cpu_data.x86_stepping >= 0x1))
319 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
320 
321 	if (boot_cpu_data.x86 == 0x15)
322 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
323 
324 	/* L3 cache partitioning is supported on family 0x15 */
325 	if (boot_cpu_data.x86 == 0x15)
326 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
327 
328 	return 0;
329 }
330 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
331 
332 /*
333  * Ignores subdevice/subvendor but as far as I can figure out
334  * they're useless anyways
335  */
336 bool __init early_is_amd_nb(u32 device)
337 {
338 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
339 	const struct pci_device_id *id;
340 	u32 vendor = device & 0xffff;
341 
342 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
343 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
344 		return false;
345 
346 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
347 		misc_ids = hygon_nb_misc_ids;
348 
349 	device >>= 16;
350 	for (id = misc_ids; id->vendor; id++)
351 		if (vendor == id->vendor && device == id->device)
352 			return true;
353 	return false;
354 }
355 
356 struct resource *amd_get_mmconfig_range(struct resource *res)
357 {
358 	u32 address;
359 	u64 base, msr;
360 	unsigned int segn_busn_bits;
361 
362 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
363 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
364 		return NULL;
365 
366 	/* assume all cpus from fam10h have mmconfig */
367 	if (boot_cpu_data.x86 < 0x10)
368 		return NULL;
369 
370 	address = MSR_FAM10H_MMIO_CONF_BASE;
371 	rdmsrl(address, msr);
372 
373 	/* mmconfig is not enabled */
374 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
375 		return NULL;
376 
377 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
378 
379 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
380 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
381 
382 	res->flags = IORESOURCE_MEM;
383 	res->start = base;
384 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
385 	return res;
386 }
387 
388 int amd_get_subcaches(int cpu)
389 {
390 	struct pci_dev *link = node_to_amd_nb(topology_die_id(cpu))->link;
391 	unsigned int mask;
392 
393 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
394 		return 0;
395 
396 	pci_read_config_dword(link, 0x1d4, &mask);
397 
398 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
399 }
400 
401 int amd_set_subcaches(int cpu, unsigned long mask)
402 {
403 	static unsigned int reset, ban;
404 	struct amd_northbridge *nb = node_to_amd_nb(topology_die_id(cpu));
405 	unsigned int reg;
406 	int cuid;
407 
408 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
409 		return -EINVAL;
410 
411 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
412 	if (reset == 0) {
413 		pci_read_config_dword(nb->link, 0x1d4, &reset);
414 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
415 		ban &= 0x180000;
416 	}
417 
418 	/* deactivate BAN mode if any subcaches are to be disabled */
419 	if (mask != 0xf) {
420 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
421 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
422 	}
423 
424 	cuid = cpu_data(cpu).cpu_core_id;
425 	mask <<= 4 * cuid;
426 	mask |= (0xf ^ (1 << cuid)) << 26;
427 
428 	pci_write_config_dword(nb->link, 0x1d4, mask);
429 
430 	/* reset BAN mode if L3 partitioning returned to reset state */
431 	pci_read_config_dword(nb->link, 0x1d4, &reg);
432 	if (reg == reset) {
433 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
434 		reg &= ~0x180000;
435 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
436 	}
437 
438 	return 0;
439 }
440 
441 static void amd_cache_gart(void)
442 {
443 	u16 i;
444 
445 	if (!amd_nb_has_feature(AMD_NB_GART))
446 		return;
447 
448 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
449 	if (!flush_words) {
450 		amd_northbridges.flags &= ~AMD_NB_GART;
451 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
452 		return;
453 	}
454 
455 	for (i = 0; i != amd_northbridges.num; i++)
456 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
457 }
458 
459 void amd_flush_garts(void)
460 {
461 	int flushed, i;
462 	unsigned long flags;
463 	static DEFINE_SPINLOCK(gart_lock);
464 
465 	if (!amd_nb_has_feature(AMD_NB_GART))
466 		return;
467 
468 	/*
469 	 * Avoid races between AGP and IOMMU. In theory it's not needed
470 	 * but I'm not sure if the hardware won't lose flush requests
471 	 * when another is pending. This whole thing is so expensive anyways
472 	 * that it doesn't matter to serialize more. -AK
473 	 */
474 	spin_lock_irqsave(&gart_lock, flags);
475 	flushed = 0;
476 	for (i = 0; i < amd_northbridges.num; i++) {
477 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
478 				       flush_words[i] | 1);
479 		flushed++;
480 	}
481 	for (i = 0; i < amd_northbridges.num; i++) {
482 		u32 w;
483 		/* Make sure the hardware actually executed the flush*/
484 		for (;;) {
485 			pci_read_config_dword(node_to_amd_nb(i)->misc,
486 					      0x9c, &w);
487 			if (!(w & 1))
488 				break;
489 			cpu_relax();
490 		}
491 	}
492 	spin_unlock_irqrestore(&gart_lock, flags);
493 	if (!flushed)
494 		pr_notice("nothing to flush?\n");
495 }
496 EXPORT_SYMBOL_GPL(amd_flush_garts);
497 
498 static void __fix_erratum_688(void *info)
499 {
500 #define MSR_AMD64_IC_CFG 0xC0011021
501 
502 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
503 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
504 }
505 
506 /* Apply erratum 688 fix so machines without a BIOS fix work. */
507 static __init void fix_erratum_688(void)
508 {
509 	struct pci_dev *F4;
510 	u32 val;
511 
512 	if (boot_cpu_data.x86 != 0x14)
513 		return;
514 
515 	if (!amd_northbridges.num)
516 		return;
517 
518 	F4 = node_to_amd_nb(0)->link;
519 	if (!F4)
520 		return;
521 
522 	if (pci_read_config_dword(F4, 0x164, &val))
523 		return;
524 
525 	if (val & BIT(2))
526 		return;
527 
528 	on_each_cpu(__fix_erratum_688, NULL, 0);
529 
530 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
531 }
532 
533 static __init int init_amd_nbs(void)
534 {
535 	amd_cache_northbridges();
536 	amd_cache_gart();
537 
538 	fix_erratum_688();
539 
540 	return 0;
541 }
542 
543 /* This has to go after the PCI subsystem */
544 fs_initcall(init_amd_nbs);
545