xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Shared support code for AMD K8 northbridges and derivates.
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 
29 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
30 static DEFINE_MUTEX(smn_mutex);
31 
32 static u32 *flush_words;
33 
34 static const struct pci_device_id amd_root_ids[] = {
35 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
36 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
37 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
38 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_ROOT) },
39 	{}
40 };
41 
42 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
43 
44 static const struct pci_device_id amd_nb_misc_ids[] = {
45 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
46 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
47 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
48 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
49 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
50 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
51 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
52 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
53 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
54 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
55 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
56 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F3) },
57 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
58 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
59 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
60 	{}
61 };
62 
63 static const struct pci_device_id amd_nb_link_ids[] = {
64 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
65 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
66 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
67 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
68 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
69 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
70 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
71 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
72 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
73 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
74 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
75 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
76 	{}
77 };
78 
79 static const struct pci_device_id hygon_root_ids[] = {
80 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
81 	{}
82 };
83 
84 static const struct pci_device_id hygon_nb_misc_ids[] = {
85 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
86 	{}
87 };
88 
89 static const struct pci_device_id hygon_nb_link_ids[] = {
90 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
91 	{}
92 };
93 
94 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
95 	{ 0x00, 0x18, 0x20 },
96 	{ 0xff, 0x00, 0x20 },
97 	{ 0xfe, 0x00, 0x20 },
98 	{ }
99 };
100 
101 static struct amd_northbridge_info amd_northbridges;
102 
103 u16 amd_nb_num(void)
104 {
105 	return amd_northbridges.num;
106 }
107 EXPORT_SYMBOL_GPL(amd_nb_num);
108 
109 bool amd_nb_has_feature(unsigned int feature)
110 {
111 	return ((amd_northbridges.flags & feature) == feature);
112 }
113 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
114 
115 struct amd_northbridge *node_to_amd_nb(int node)
116 {
117 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
118 }
119 EXPORT_SYMBOL_GPL(node_to_amd_nb);
120 
121 static struct pci_dev *next_northbridge(struct pci_dev *dev,
122 					const struct pci_device_id *ids)
123 {
124 	do {
125 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
126 		if (!dev)
127 			break;
128 	} while (!pci_match_id(ids, dev));
129 	return dev;
130 }
131 
132 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
133 {
134 	struct pci_dev *root;
135 	int err = -ENODEV;
136 
137 	if (node >= amd_northbridges.num)
138 		goto out;
139 
140 	root = node_to_amd_nb(node)->root;
141 	if (!root)
142 		goto out;
143 
144 	mutex_lock(&smn_mutex);
145 
146 	err = pci_write_config_dword(root, 0x60, address);
147 	if (err) {
148 		pr_warn("Error programming SMN address 0x%x.\n", address);
149 		goto out_unlock;
150 	}
151 
152 	err = (write ? pci_write_config_dword(root, 0x64, *value)
153 		     : pci_read_config_dword(root, 0x64, value));
154 	if (err)
155 		pr_warn("Error %s SMN address 0x%x.\n",
156 			(write ? "writing to" : "reading from"), address);
157 
158 out_unlock:
159 	mutex_unlock(&smn_mutex);
160 
161 out:
162 	return err;
163 }
164 
165 int amd_smn_read(u16 node, u32 address, u32 *value)
166 {
167 	return __amd_smn_rw(node, address, value, false);
168 }
169 EXPORT_SYMBOL_GPL(amd_smn_read);
170 
171 int amd_smn_write(u16 node, u32 address, u32 value)
172 {
173 	return __amd_smn_rw(node, address, &value, true);
174 }
175 EXPORT_SYMBOL_GPL(amd_smn_write);
176 
177 /*
178  * Data Fabric Indirect Access uses FICAA/FICAD.
179  *
180  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
181  * on the device's Instance Id and the PCI function and register offset of
182  * the desired register.
183  *
184  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
185  * and FICAD HI registers but so far we only need the LO register.
186  */
187 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
188 {
189 	struct pci_dev *F4;
190 	u32 ficaa;
191 	int err = -ENODEV;
192 
193 	if (node >= amd_northbridges.num)
194 		goto out;
195 
196 	F4 = node_to_amd_nb(node)->link;
197 	if (!F4)
198 		goto out;
199 
200 	ficaa  = 1;
201 	ficaa |= reg & 0x3FC;
202 	ficaa |= (func & 0x7) << 11;
203 	ficaa |= instance_id << 16;
204 
205 	mutex_lock(&smn_mutex);
206 
207 	err = pci_write_config_dword(F4, 0x5C, ficaa);
208 	if (err) {
209 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
210 		goto out_unlock;
211 	}
212 
213 	err = pci_read_config_dword(F4, 0x98, lo);
214 	if (err)
215 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
216 
217 out_unlock:
218 	mutex_unlock(&smn_mutex);
219 
220 out:
221 	return err;
222 }
223 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
224 
225 int amd_cache_northbridges(void)
226 {
227 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
228 	const struct pci_device_id *link_ids = amd_nb_link_ids;
229 	const struct pci_device_id *root_ids = amd_root_ids;
230 	struct pci_dev *root, *misc, *link;
231 	struct amd_northbridge *nb;
232 	u16 roots_per_misc = 0;
233 	u16 misc_count = 0;
234 	u16 root_count = 0;
235 	u16 i, j;
236 
237 	if (amd_northbridges.num)
238 		return 0;
239 
240 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
241 		root_ids = hygon_root_ids;
242 		misc_ids = hygon_nb_misc_ids;
243 		link_ids = hygon_nb_link_ids;
244 	}
245 
246 	misc = NULL;
247 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
248 		misc_count++;
249 
250 	if (!misc_count)
251 		return -ENODEV;
252 
253 	root = NULL;
254 	while ((root = next_northbridge(root, root_ids)) != NULL)
255 		root_count++;
256 
257 	if (root_count) {
258 		roots_per_misc = root_count / misc_count;
259 
260 		/*
261 		 * There should be _exactly_ N roots for each DF/SMN
262 		 * interface.
263 		 */
264 		if (!roots_per_misc || (root_count % roots_per_misc)) {
265 			pr_info("Unsupported AMD DF/PCI configuration found\n");
266 			return -ENODEV;
267 		}
268 	}
269 
270 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
271 	if (!nb)
272 		return -ENOMEM;
273 
274 	amd_northbridges.nb = nb;
275 	amd_northbridges.num = misc_count;
276 
277 	link = misc = root = NULL;
278 	for (i = 0; i < amd_northbridges.num; i++) {
279 		node_to_amd_nb(i)->root = root =
280 			next_northbridge(root, root_ids);
281 		node_to_amd_nb(i)->misc = misc =
282 			next_northbridge(misc, misc_ids);
283 		node_to_amd_nb(i)->link = link =
284 			next_northbridge(link, link_ids);
285 
286 		/*
287 		 * If there are more PCI root devices than data fabric/
288 		 * system management network interfaces, then the (N)
289 		 * PCI roots per DF/SMN interface are functionally the
290 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
291 		 * PCI roots should be skipped per DF/SMN interface so
292 		 * the following DF/SMN interfaces get mapped to
293 		 * correct PCI roots.
294 		 */
295 		for (j = 1; j < roots_per_misc; j++)
296 			root = next_northbridge(root, root_ids);
297 	}
298 
299 	if (amd_gart_present())
300 		amd_northbridges.flags |= AMD_NB_GART;
301 
302 	/*
303 	 * Check for L3 cache presence.
304 	 */
305 	if (!cpuid_edx(0x80000006))
306 		return 0;
307 
308 	/*
309 	 * Some CPU families support L3 Cache Index Disable. There are some
310 	 * limitations because of E382 and E388 on family 0x10.
311 	 */
312 	if (boot_cpu_data.x86 == 0x10 &&
313 	    boot_cpu_data.x86_model >= 0x8 &&
314 	    (boot_cpu_data.x86_model > 0x9 ||
315 	     boot_cpu_data.x86_stepping >= 0x1))
316 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
317 
318 	if (boot_cpu_data.x86 == 0x15)
319 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
320 
321 	/* L3 cache partitioning is supported on family 0x15 */
322 	if (boot_cpu_data.x86 == 0x15)
323 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
324 
325 	return 0;
326 }
327 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
328 
329 /*
330  * Ignores subdevice/subvendor but as far as I can figure out
331  * they're useless anyways
332  */
333 bool __init early_is_amd_nb(u32 device)
334 {
335 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
336 	const struct pci_device_id *id;
337 	u32 vendor = device & 0xffff;
338 
339 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
340 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
341 		return false;
342 
343 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
344 		misc_ids = hygon_nb_misc_ids;
345 
346 	device >>= 16;
347 	for (id = misc_ids; id->vendor; id++)
348 		if (vendor == id->vendor && device == id->device)
349 			return true;
350 	return false;
351 }
352 
353 struct resource *amd_get_mmconfig_range(struct resource *res)
354 {
355 	u32 address;
356 	u64 base, msr;
357 	unsigned int segn_busn_bits;
358 
359 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
360 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
361 		return NULL;
362 
363 	/* assume all cpus from fam10h have mmconfig */
364 	if (boot_cpu_data.x86 < 0x10)
365 		return NULL;
366 
367 	address = MSR_FAM10H_MMIO_CONF_BASE;
368 	rdmsrl(address, msr);
369 
370 	/* mmconfig is not enabled */
371 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
372 		return NULL;
373 
374 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
375 
376 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
377 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
378 
379 	res->flags = IORESOURCE_MEM;
380 	res->start = base;
381 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
382 	return res;
383 }
384 
385 int amd_get_subcaches(int cpu)
386 {
387 	struct pci_dev *link = node_to_amd_nb(topology_die_id(cpu))->link;
388 	unsigned int mask;
389 
390 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
391 		return 0;
392 
393 	pci_read_config_dword(link, 0x1d4, &mask);
394 
395 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
396 }
397 
398 int amd_set_subcaches(int cpu, unsigned long mask)
399 {
400 	static unsigned int reset, ban;
401 	struct amd_northbridge *nb = node_to_amd_nb(topology_die_id(cpu));
402 	unsigned int reg;
403 	int cuid;
404 
405 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
406 		return -EINVAL;
407 
408 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
409 	if (reset == 0) {
410 		pci_read_config_dword(nb->link, 0x1d4, &reset);
411 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
412 		ban &= 0x180000;
413 	}
414 
415 	/* deactivate BAN mode if any subcaches are to be disabled */
416 	if (mask != 0xf) {
417 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
418 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
419 	}
420 
421 	cuid = cpu_data(cpu).cpu_core_id;
422 	mask <<= 4 * cuid;
423 	mask |= (0xf ^ (1 << cuid)) << 26;
424 
425 	pci_write_config_dword(nb->link, 0x1d4, mask);
426 
427 	/* reset BAN mode if L3 partitioning returned to reset state */
428 	pci_read_config_dword(nb->link, 0x1d4, &reg);
429 	if (reg == reset) {
430 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
431 		reg &= ~0x180000;
432 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
433 	}
434 
435 	return 0;
436 }
437 
438 static void amd_cache_gart(void)
439 {
440 	u16 i;
441 
442 	if (!amd_nb_has_feature(AMD_NB_GART))
443 		return;
444 
445 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
446 	if (!flush_words) {
447 		amd_northbridges.flags &= ~AMD_NB_GART;
448 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
449 		return;
450 	}
451 
452 	for (i = 0; i != amd_northbridges.num; i++)
453 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
454 }
455 
456 void amd_flush_garts(void)
457 {
458 	int flushed, i;
459 	unsigned long flags;
460 	static DEFINE_SPINLOCK(gart_lock);
461 
462 	if (!amd_nb_has_feature(AMD_NB_GART))
463 		return;
464 
465 	/*
466 	 * Avoid races between AGP and IOMMU. In theory it's not needed
467 	 * but I'm not sure if the hardware won't lose flush requests
468 	 * when another is pending. This whole thing is so expensive anyways
469 	 * that it doesn't matter to serialize more. -AK
470 	 */
471 	spin_lock_irqsave(&gart_lock, flags);
472 	flushed = 0;
473 	for (i = 0; i < amd_northbridges.num; i++) {
474 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
475 				       flush_words[i] | 1);
476 		flushed++;
477 	}
478 	for (i = 0; i < amd_northbridges.num; i++) {
479 		u32 w;
480 		/* Make sure the hardware actually executed the flush*/
481 		for (;;) {
482 			pci_read_config_dword(node_to_amd_nb(i)->misc,
483 					      0x9c, &w);
484 			if (!(w & 1))
485 				break;
486 			cpu_relax();
487 		}
488 	}
489 	spin_unlock_irqrestore(&gart_lock, flags);
490 	if (!flushed)
491 		pr_notice("nothing to flush?\n");
492 }
493 EXPORT_SYMBOL_GPL(amd_flush_garts);
494 
495 static void __fix_erratum_688(void *info)
496 {
497 #define MSR_AMD64_IC_CFG 0xC0011021
498 
499 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
500 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
501 }
502 
503 /* Apply erratum 688 fix so machines without a BIOS fix work. */
504 static __init void fix_erratum_688(void)
505 {
506 	struct pci_dev *F4;
507 	u32 val;
508 
509 	if (boot_cpu_data.x86 != 0x14)
510 		return;
511 
512 	if (!amd_northbridges.num)
513 		return;
514 
515 	F4 = node_to_amd_nb(0)->link;
516 	if (!F4)
517 		return;
518 
519 	if (pci_read_config_dword(F4, 0x164, &val))
520 		return;
521 
522 	if (val & BIT(2))
523 		return;
524 
525 	on_each_cpu(__fix_erratum_688, NULL, 0);
526 
527 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
528 }
529 
530 static __init int init_amd_nbs(void)
531 {
532 	amd_cache_northbridges();
533 	amd_cache_gart();
534 
535 	fix_erratum_688();
536 
537 	return 0;
538 }
539 
540 /* This has to go after the PCI subsystem */
541 fs_initcall(init_amd_nbs);
542