xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision 15e3ae36)
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_DF_F4	0x1464
22 #define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
23 #define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
24 #define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4 0x1444
25 #define PCI_DEVICE_ID_AMD_19H_DF_F4	0x1654
26 
27 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
28 static DEFINE_MUTEX(smn_mutex);
29 
30 static u32 *flush_words;
31 
32 static const struct pci_device_id amd_root_ids[] = {
33 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
34 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
35 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
36 	{}
37 };
38 
39 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
40 
41 static const struct pci_device_id amd_nb_misc_ids[] = {
42 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
43 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
44 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
45 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
46 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
47 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
48 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
49 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
50 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
51 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
52 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
53 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
54 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
55 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
56 	{}
57 };
58 
59 static const struct pci_device_id amd_nb_link_ids[] = {
60 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
61 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
62 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
63 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
64 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
65 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
66 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
67 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
68 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
69 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
70 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
71 	{}
72 };
73 
74 static const struct pci_device_id hygon_root_ids[] = {
75 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
76 	{}
77 };
78 
79 static const struct pci_device_id hygon_nb_misc_ids[] = {
80 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
81 	{}
82 };
83 
84 static const struct pci_device_id hygon_nb_link_ids[] = {
85 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
86 	{}
87 };
88 
89 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
90 	{ 0x00, 0x18, 0x20 },
91 	{ 0xff, 0x00, 0x20 },
92 	{ 0xfe, 0x00, 0x20 },
93 	{ }
94 };
95 
96 static struct amd_northbridge_info amd_northbridges;
97 
98 u16 amd_nb_num(void)
99 {
100 	return amd_northbridges.num;
101 }
102 EXPORT_SYMBOL_GPL(amd_nb_num);
103 
104 bool amd_nb_has_feature(unsigned int feature)
105 {
106 	return ((amd_northbridges.flags & feature) == feature);
107 }
108 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
109 
110 struct amd_northbridge *node_to_amd_nb(int node)
111 {
112 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
113 }
114 EXPORT_SYMBOL_GPL(node_to_amd_nb);
115 
116 static struct pci_dev *next_northbridge(struct pci_dev *dev,
117 					const struct pci_device_id *ids)
118 {
119 	do {
120 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
121 		if (!dev)
122 			break;
123 	} while (!pci_match_id(ids, dev));
124 	return dev;
125 }
126 
127 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
128 {
129 	struct pci_dev *root;
130 	int err = -ENODEV;
131 
132 	if (node >= amd_northbridges.num)
133 		goto out;
134 
135 	root = node_to_amd_nb(node)->root;
136 	if (!root)
137 		goto out;
138 
139 	mutex_lock(&smn_mutex);
140 
141 	err = pci_write_config_dword(root, 0x60, address);
142 	if (err) {
143 		pr_warn("Error programming SMN address 0x%x.\n", address);
144 		goto out_unlock;
145 	}
146 
147 	err = (write ? pci_write_config_dword(root, 0x64, *value)
148 		     : pci_read_config_dword(root, 0x64, value));
149 	if (err)
150 		pr_warn("Error %s SMN address 0x%x.\n",
151 			(write ? "writing to" : "reading from"), address);
152 
153 out_unlock:
154 	mutex_unlock(&smn_mutex);
155 
156 out:
157 	return err;
158 }
159 
160 int amd_smn_read(u16 node, u32 address, u32 *value)
161 {
162 	return __amd_smn_rw(node, address, value, false);
163 }
164 EXPORT_SYMBOL_GPL(amd_smn_read);
165 
166 int amd_smn_write(u16 node, u32 address, u32 value)
167 {
168 	return __amd_smn_rw(node, address, &value, true);
169 }
170 EXPORT_SYMBOL_GPL(amd_smn_write);
171 
172 /*
173  * Data Fabric Indirect Access uses FICAA/FICAD.
174  *
175  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
176  * on the device's Instance Id and the PCI function and register offset of
177  * the desired register.
178  *
179  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
180  * and FICAD HI registers but so far we only need the LO register.
181  */
182 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
183 {
184 	struct pci_dev *F4;
185 	u32 ficaa;
186 	int err = -ENODEV;
187 
188 	if (node >= amd_northbridges.num)
189 		goto out;
190 
191 	F4 = node_to_amd_nb(node)->link;
192 	if (!F4)
193 		goto out;
194 
195 	ficaa  = 1;
196 	ficaa |= reg & 0x3FC;
197 	ficaa |= (func & 0x7) << 11;
198 	ficaa |= instance_id << 16;
199 
200 	mutex_lock(&smn_mutex);
201 
202 	err = pci_write_config_dword(F4, 0x5C, ficaa);
203 	if (err) {
204 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
205 		goto out_unlock;
206 	}
207 
208 	err = pci_read_config_dword(F4, 0x98, lo);
209 	if (err)
210 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
211 
212 out_unlock:
213 	mutex_unlock(&smn_mutex);
214 
215 out:
216 	return err;
217 }
218 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
219 
220 int amd_cache_northbridges(void)
221 {
222 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
223 	const struct pci_device_id *link_ids = amd_nb_link_ids;
224 	const struct pci_device_id *root_ids = amd_root_ids;
225 	struct pci_dev *root, *misc, *link;
226 	struct amd_northbridge *nb;
227 	u16 roots_per_misc = 0;
228 	u16 misc_count = 0;
229 	u16 root_count = 0;
230 	u16 i, j;
231 
232 	if (amd_northbridges.num)
233 		return 0;
234 
235 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
236 		root_ids = hygon_root_ids;
237 		misc_ids = hygon_nb_misc_ids;
238 		link_ids = hygon_nb_link_ids;
239 	}
240 
241 	misc = NULL;
242 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
243 		misc_count++;
244 
245 	if (!misc_count)
246 		return -ENODEV;
247 
248 	root = NULL;
249 	while ((root = next_northbridge(root, root_ids)) != NULL)
250 		root_count++;
251 
252 	if (root_count) {
253 		roots_per_misc = root_count / misc_count;
254 
255 		/*
256 		 * There should be _exactly_ N roots for each DF/SMN
257 		 * interface.
258 		 */
259 		if (!roots_per_misc || (root_count % roots_per_misc)) {
260 			pr_info("Unsupported AMD DF/PCI configuration found\n");
261 			return -ENODEV;
262 		}
263 	}
264 
265 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
266 	if (!nb)
267 		return -ENOMEM;
268 
269 	amd_northbridges.nb = nb;
270 	amd_northbridges.num = misc_count;
271 
272 	link = misc = root = NULL;
273 	for (i = 0; i < amd_northbridges.num; i++) {
274 		node_to_amd_nb(i)->root = root =
275 			next_northbridge(root, root_ids);
276 		node_to_amd_nb(i)->misc = misc =
277 			next_northbridge(misc, misc_ids);
278 		node_to_amd_nb(i)->link = link =
279 			next_northbridge(link, link_ids);
280 
281 		/*
282 		 * If there are more PCI root devices than data fabric/
283 		 * system management network interfaces, then the (N)
284 		 * PCI roots per DF/SMN interface are functionally the
285 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
286 		 * PCI roots should be skipped per DF/SMN interface so
287 		 * the following DF/SMN interfaces get mapped to
288 		 * correct PCI roots.
289 		 */
290 		for (j = 1; j < roots_per_misc; j++)
291 			root = next_northbridge(root, root_ids);
292 	}
293 
294 	if (amd_gart_present())
295 		amd_northbridges.flags |= AMD_NB_GART;
296 
297 	/*
298 	 * Check for L3 cache presence.
299 	 */
300 	if (!cpuid_edx(0x80000006))
301 		return 0;
302 
303 	/*
304 	 * Some CPU families support L3 Cache Index Disable. There are some
305 	 * limitations because of E382 and E388 on family 0x10.
306 	 */
307 	if (boot_cpu_data.x86 == 0x10 &&
308 	    boot_cpu_data.x86_model >= 0x8 &&
309 	    (boot_cpu_data.x86_model > 0x9 ||
310 	     boot_cpu_data.x86_stepping >= 0x1))
311 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
312 
313 	if (boot_cpu_data.x86 == 0x15)
314 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
315 
316 	/* L3 cache partitioning is supported on family 0x15 */
317 	if (boot_cpu_data.x86 == 0x15)
318 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
319 
320 	return 0;
321 }
322 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
323 
324 /*
325  * Ignores subdevice/subvendor but as far as I can figure out
326  * they're useless anyways
327  */
328 bool __init early_is_amd_nb(u32 device)
329 {
330 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
331 	const struct pci_device_id *id;
332 	u32 vendor = device & 0xffff;
333 
334 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
335 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
336 		return false;
337 
338 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
339 		misc_ids = hygon_nb_misc_ids;
340 
341 	device >>= 16;
342 	for (id = misc_ids; id->vendor; id++)
343 		if (vendor == id->vendor && device == id->device)
344 			return true;
345 	return false;
346 }
347 
348 struct resource *amd_get_mmconfig_range(struct resource *res)
349 {
350 	u32 address;
351 	u64 base, msr;
352 	unsigned int segn_busn_bits;
353 
354 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
355 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
356 		return NULL;
357 
358 	/* assume all cpus from fam10h have mmconfig */
359 	if (boot_cpu_data.x86 < 0x10)
360 		return NULL;
361 
362 	address = MSR_FAM10H_MMIO_CONF_BASE;
363 	rdmsrl(address, msr);
364 
365 	/* mmconfig is not enabled */
366 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
367 		return NULL;
368 
369 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
370 
371 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
372 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
373 
374 	res->flags = IORESOURCE_MEM;
375 	res->start = base;
376 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
377 	return res;
378 }
379 
380 int amd_get_subcaches(int cpu)
381 {
382 	struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
383 	unsigned int mask;
384 
385 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
386 		return 0;
387 
388 	pci_read_config_dword(link, 0x1d4, &mask);
389 
390 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
391 }
392 
393 int amd_set_subcaches(int cpu, unsigned long mask)
394 {
395 	static unsigned int reset, ban;
396 	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));
397 	unsigned int reg;
398 	int cuid;
399 
400 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
401 		return -EINVAL;
402 
403 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
404 	if (reset == 0) {
405 		pci_read_config_dword(nb->link, 0x1d4, &reset);
406 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
407 		ban &= 0x180000;
408 	}
409 
410 	/* deactivate BAN mode if any subcaches are to be disabled */
411 	if (mask != 0xf) {
412 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
413 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
414 	}
415 
416 	cuid = cpu_data(cpu).cpu_core_id;
417 	mask <<= 4 * cuid;
418 	mask |= (0xf ^ (1 << cuid)) << 26;
419 
420 	pci_write_config_dword(nb->link, 0x1d4, mask);
421 
422 	/* reset BAN mode if L3 partitioning returned to reset state */
423 	pci_read_config_dword(nb->link, 0x1d4, &reg);
424 	if (reg == reset) {
425 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
426 		reg &= ~0x180000;
427 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
428 	}
429 
430 	return 0;
431 }
432 
433 static void amd_cache_gart(void)
434 {
435 	u16 i;
436 
437 	if (!amd_nb_has_feature(AMD_NB_GART))
438 		return;
439 
440 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
441 	if (!flush_words) {
442 		amd_northbridges.flags &= ~AMD_NB_GART;
443 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
444 		return;
445 	}
446 
447 	for (i = 0; i != amd_northbridges.num; i++)
448 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
449 }
450 
451 void amd_flush_garts(void)
452 {
453 	int flushed, i;
454 	unsigned long flags;
455 	static DEFINE_SPINLOCK(gart_lock);
456 
457 	if (!amd_nb_has_feature(AMD_NB_GART))
458 		return;
459 
460 	/*
461 	 * Avoid races between AGP and IOMMU. In theory it's not needed
462 	 * but I'm not sure if the hardware won't lose flush requests
463 	 * when another is pending. This whole thing is so expensive anyways
464 	 * that it doesn't matter to serialize more. -AK
465 	 */
466 	spin_lock_irqsave(&gart_lock, flags);
467 	flushed = 0;
468 	for (i = 0; i < amd_northbridges.num; i++) {
469 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
470 				       flush_words[i] | 1);
471 		flushed++;
472 	}
473 	for (i = 0; i < amd_northbridges.num; i++) {
474 		u32 w;
475 		/* Make sure the hardware actually executed the flush*/
476 		for (;;) {
477 			pci_read_config_dword(node_to_amd_nb(i)->misc,
478 					      0x9c, &w);
479 			if (!(w & 1))
480 				break;
481 			cpu_relax();
482 		}
483 	}
484 	spin_unlock_irqrestore(&gart_lock, flags);
485 	if (!flushed)
486 		pr_notice("nothing to flush?\n");
487 }
488 EXPORT_SYMBOL_GPL(amd_flush_garts);
489 
490 static void __fix_erratum_688(void *info)
491 {
492 #define MSR_AMD64_IC_CFG 0xC0011021
493 
494 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
495 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
496 }
497 
498 /* Apply erratum 688 fix so machines without a BIOS fix work. */
499 static __init void fix_erratum_688(void)
500 {
501 	struct pci_dev *F4;
502 	u32 val;
503 
504 	if (boot_cpu_data.x86 != 0x14)
505 		return;
506 
507 	if (!amd_northbridges.num)
508 		return;
509 
510 	F4 = node_to_amd_nb(0)->link;
511 	if (!F4)
512 		return;
513 
514 	if (pci_read_config_dword(F4, 0x164, &val))
515 		return;
516 
517 	if (val & BIT(2))
518 		return;
519 
520 	on_each_cpu(__fix_erratum_688, NULL, 0);
521 
522 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
523 }
524 
525 static __init int init_amd_nbs(void)
526 {
527 	amd_cache_northbridges();
528 	amd_cache_gart();
529 
530 	fix_erratum_688();
531 
532 	return 0;
533 }
534 
535 /* This has to go after the PCI subsystem */
536 fs_initcall(init_amd_nbs);
537