xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision b7b3c35e)
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_19H_M10H_ROOT	0x14a4
23 #define PCI_DEVICE_ID_AMD_17H_DF_F4	0x1464
24 #define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
25 #define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
26 #define PCI_DEVICE_ID_AMD_17H_M60H_DF_F4 0x144c
27 #define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4 0x1444
28 #define PCI_DEVICE_ID_AMD_19H_DF_F4	0x1654
29 #define PCI_DEVICE_ID_AMD_19H_M10H_DF_F4 0x14b1
30 #define PCI_DEVICE_ID_AMD_19H_M40H_ROOT	0x14b5
31 #define PCI_DEVICE_ID_AMD_19H_M40H_DF_F4 0x167d
32 #define PCI_DEVICE_ID_AMD_19H_M50H_DF_F4 0x166e
33 
34 /* Protect the PCI config register pairs used for SMN. */
35 static DEFINE_MUTEX(smn_mutex);
36 
37 static u32 *flush_words;
38 
39 static const struct pci_device_id amd_root_ids[] = {
40 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
41 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
42 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
43 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_ROOT) },
44 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_ROOT) },
45 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_ROOT) },
46 	{}
47 };
48 
49 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
50 
51 static const struct pci_device_id amd_nb_misc_ids[] = {
52 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
53 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
54 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
55 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
56 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
57 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
58 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
59 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
60 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
61 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
62 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
63 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F3) },
64 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
65 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
66 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
67 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F3) },
68 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F3) },
69 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F3) },
70 	{}
71 };
72 
73 static const struct pci_device_id amd_nb_link_ids[] = {
74 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
75 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
76 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
77 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
78 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
79 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
80 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
81 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
82 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
83 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
84 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
85 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F4) },
86 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F4) },
87 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
88 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
89 	{}
90 };
91 
92 static const struct pci_device_id hygon_root_ids[] = {
93 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
94 	{}
95 };
96 
97 static const struct pci_device_id hygon_nb_misc_ids[] = {
98 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
99 	{}
100 };
101 
102 static const struct pci_device_id hygon_nb_link_ids[] = {
103 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
104 	{}
105 };
106 
107 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
108 	{ 0x00, 0x18, 0x20 },
109 	{ 0xff, 0x00, 0x20 },
110 	{ 0xfe, 0x00, 0x20 },
111 	{ }
112 };
113 
114 static struct amd_northbridge_info amd_northbridges;
115 
116 u16 amd_nb_num(void)
117 {
118 	return amd_northbridges.num;
119 }
120 EXPORT_SYMBOL_GPL(amd_nb_num);
121 
122 bool amd_nb_has_feature(unsigned int feature)
123 {
124 	return ((amd_northbridges.flags & feature) == feature);
125 }
126 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
127 
128 struct amd_northbridge *node_to_amd_nb(int node)
129 {
130 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
131 }
132 EXPORT_SYMBOL_GPL(node_to_amd_nb);
133 
134 static struct pci_dev *next_northbridge(struct pci_dev *dev,
135 					const struct pci_device_id *ids)
136 {
137 	do {
138 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
139 		if (!dev)
140 			break;
141 	} while (!pci_match_id(ids, dev));
142 	return dev;
143 }
144 
145 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
146 {
147 	struct pci_dev *root;
148 	int err = -ENODEV;
149 
150 	if (node >= amd_northbridges.num)
151 		goto out;
152 
153 	root = node_to_amd_nb(node)->root;
154 	if (!root)
155 		goto out;
156 
157 	mutex_lock(&smn_mutex);
158 
159 	err = pci_write_config_dword(root, 0x60, address);
160 	if (err) {
161 		pr_warn("Error programming SMN address 0x%x.\n", address);
162 		goto out_unlock;
163 	}
164 
165 	err = (write ? pci_write_config_dword(root, 0x64, *value)
166 		     : pci_read_config_dword(root, 0x64, value));
167 	if (err)
168 		pr_warn("Error %s SMN address 0x%x.\n",
169 			(write ? "writing to" : "reading from"), address);
170 
171 out_unlock:
172 	mutex_unlock(&smn_mutex);
173 
174 out:
175 	return err;
176 }
177 
178 int amd_smn_read(u16 node, u32 address, u32 *value)
179 {
180 	return __amd_smn_rw(node, address, value, false);
181 }
182 EXPORT_SYMBOL_GPL(amd_smn_read);
183 
184 int amd_smn_write(u16 node, u32 address, u32 value)
185 {
186 	return __amd_smn_rw(node, address, &value, true);
187 }
188 EXPORT_SYMBOL_GPL(amd_smn_write);
189 
190 
191 int amd_cache_northbridges(void)
192 {
193 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
194 	const struct pci_device_id *link_ids = amd_nb_link_ids;
195 	const struct pci_device_id *root_ids = amd_root_ids;
196 	struct pci_dev *root, *misc, *link;
197 	struct amd_northbridge *nb;
198 	u16 roots_per_misc = 0;
199 	u16 misc_count = 0;
200 	u16 root_count = 0;
201 	u16 i, j;
202 
203 	if (amd_northbridges.num)
204 		return 0;
205 
206 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
207 		root_ids = hygon_root_ids;
208 		misc_ids = hygon_nb_misc_ids;
209 		link_ids = hygon_nb_link_ids;
210 	}
211 
212 	misc = NULL;
213 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
214 		misc_count++;
215 
216 	if (!misc_count)
217 		return -ENODEV;
218 
219 	root = NULL;
220 	while ((root = next_northbridge(root, root_ids)) != NULL)
221 		root_count++;
222 
223 	if (root_count) {
224 		roots_per_misc = root_count / misc_count;
225 
226 		/*
227 		 * There should be _exactly_ N roots for each DF/SMN
228 		 * interface.
229 		 */
230 		if (!roots_per_misc || (root_count % roots_per_misc)) {
231 			pr_info("Unsupported AMD DF/PCI configuration found\n");
232 			return -ENODEV;
233 		}
234 	}
235 
236 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
237 	if (!nb)
238 		return -ENOMEM;
239 
240 	amd_northbridges.nb = nb;
241 	amd_northbridges.num = misc_count;
242 
243 	link = misc = root = NULL;
244 	for (i = 0; i < amd_northbridges.num; i++) {
245 		node_to_amd_nb(i)->root = root =
246 			next_northbridge(root, root_ids);
247 		node_to_amd_nb(i)->misc = misc =
248 			next_northbridge(misc, misc_ids);
249 		node_to_amd_nb(i)->link = link =
250 			next_northbridge(link, link_ids);
251 
252 		/*
253 		 * If there are more PCI root devices than data fabric/
254 		 * system management network interfaces, then the (N)
255 		 * PCI roots per DF/SMN interface are functionally the
256 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
257 		 * PCI roots should be skipped per DF/SMN interface so
258 		 * the following DF/SMN interfaces get mapped to
259 		 * correct PCI roots.
260 		 */
261 		for (j = 1; j < roots_per_misc; j++)
262 			root = next_northbridge(root, root_ids);
263 	}
264 
265 	if (amd_gart_present())
266 		amd_northbridges.flags |= AMD_NB_GART;
267 
268 	/*
269 	 * Check for L3 cache presence.
270 	 */
271 	if (!cpuid_edx(0x80000006))
272 		return 0;
273 
274 	/*
275 	 * Some CPU families support L3 Cache Index Disable. There are some
276 	 * limitations because of E382 and E388 on family 0x10.
277 	 */
278 	if (boot_cpu_data.x86 == 0x10 &&
279 	    boot_cpu_data.x86_model >= 0x8 &&
280 	    (boot_cpu_data.x86_model > 0x9 ||
281 	     boot_cpu_data.x86_stepping >= 0x1))
282 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
283 
284 	if (boot_cpu_data.x86 == 0x15)
285 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
286 
287 	/* L3 cache partitioning is supported on family 0x15 */
288 	if (boot_cpu_data.x86 == 0x15)
289 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
290 
291 	return 0;
292 }
293 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
294 
295 /*
296  * Ignores subdevice/subvendor but as far as I can figure out
297  * they're useless anyways
298  */
299 bool __init early_is_amd_nb(u32 device)
300 {
301 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
302 	const struct pci_device_id *id;
303 	u32 vendor = device & 0xffff;
304 
305 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
306 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
307 		return false;
308 
309 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
310 		misc_ids = hygon_nb_misc_ids;
311 
312 	device >>= 16;
313 	for (id = misc_ids; id->vendor; id++)
314 		if (vendor == id->vendor && device == id->device)
315 			return true;
316 	return false;
317 }
318 
319 struct resource *amd_get_mmconfig_range(struct resource *res)
320 {
321 	u32 address;
322 	u64 base, msr;
323 	unsigned int segn_busn_bits;
324 
325 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
326 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
327 		return NULL;
328 
329 	/* assume all cpus from fam10h have mmconfig */
330 	if (boot_cpu_data.x86 < 0x10)
331 		return NULL;
332 
333 	address = MSR_FAM10H_MMIO_CONF_BASE;
334 	rdmsrl(address, msr);
335 
336 	/* mmconfig is not enabled */
337 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
338 		return NULL;
339 
340 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
341 
342 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
343 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
344 
345 	res->flags = IORESOURCE_MEM;
346 	res->start = base;
347 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
348 	return res;
349 }
350 
351 int amd_get_subcaches(int cpu)
352 {
353 	struct pci_dev *link = node_to_amd_nb(topology_die_id(cpu))->link;
354 	unsigned int mask;
355 
356 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
357 		return 0;
358 
359 	pci_read_config_dword(link, 0x1d4, &mask);
360 
361 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
362 }
363 
364 int amd_set_subcaches(int cpu, unsigned long mask)
365 {
366 	static unsigned int reset, ban;
367 	struct amd_northbridge *nb = node_to_amd_nb(topology_die_id(cpu));
368 	unsigned int reg;
369 	int cuid;
370 
371 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
372 		return -EINVAL;
373 
374 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
375 	if (reset == 0) {
376 		pci_read_config_dword(nb->link, 0x1d4, &reset);
377 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
378 		ban &= 0x180000;
379 	}
380 
381 	/* deactivate BAN mode if any subcaches are to be disabled */
382 	if (mask != 0xf) {
383 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
384 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
385 	}
386 
387 	cuid = cpu_data(cpu).cpu_core_id;
388 	mask <<= 4 * cuid;
389 	mask |= (0xf ^ (1 << cuid)) << 26;
390 
391 	pci_write_config_dword(nb->link, 0x1d4, mask);
392 
393 	/* reset BAN mode if L3 partitioning returned to reset state */
394 	pci_read_config_dword(nb->link, 0x1d4, &reg);
395 	if (reg == reset) {
396 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
397 		reg &= ~0x180000;
398 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
399 	}
400 
401 	return 0;
402 }
403 
404 static void amd_cache_gart(void)
405 {
406 	u16 i;
407 
408 	if (!amd_nb_has_feature(AMD_NB_GART))
409 		return;
410 
411 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
412 	if (!flush_words) {
413 		amd_northbridges.flags &= ~AMD_NB_GART;
414 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
415 		return;
416 	}
417 
418 	for (i = 0; i != amd_northbridges.num; i++)
419 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
420 }
421 
422 void amd_flush_garts(void)
423 {
424 	int flushed, i;
425 	unsigned long flags;
426 	static DEFINE_SPINLOCK(gart_lock);
427 
428 	if (!amd_nb_has_feature(AMD_NB_GART))
429 		return;
430 
431 	/*
432 	 * Avoid races between AGP and IOMMU. In theory it's not needed
433 	 * but I'm not sure if the hardware won't lose flush requests
434 	 * when another is pending. This whole thing is so expensive anyways
435 	 * that it doesn't matter to serialize more. -AK
436 	 */
437 	spin_lock_irqsave(&gart_lock, flags);
438 	flushed = 0;
439 	for (i = 0; i < amd_northbridges.num; i++) {
440 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
441 				       flush_words[i] | 1);
442 		flushed++;
443 	}
444 	for (i = 0; i < amd_northbridges.num; i++) {
445 		u32 w;
446 		/* Make sure the hardware actually executed the flush*/
447 		for (;;) {
448 			pci_read_config_dword(node_to_amd_nb(i)->misc,
449 					      0x9c, &w);
450 			if (!(w & 1))
451 				break;
452 			cpu_relax();
453 		}
454 	}
455 	spin_unlock_irqrestore(&gart_lock, flags);
456 	if (!flushed)
457 		pr_notice("nothing to flush?\n");
458 }
459 EXPORT_SYMBOL_GPL(amd_flush_garts);
460 
461 static void __fix_erratum_688(void *info)
462 {
463 #define MSR_AMD64_IC_CFG 0xC0011021
464 
465 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
466 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
467 }
468 
469 /* Apply erratum 688 fix so machines without a BIOS fix work. */
470 static __init void fix_erratum_688(void)
471 {
472 	struct pci_dev *F4;
473 	u32 val;
474 
475 	if (boot_cpu_data.x86 != 0x14)
476 		return;
477 
478 	if (!amd_northbridges.num)
479 		return;
480 
481 	F4 = node_to_amd_nb(0)->link;
482 	if (!F4)
483 		return;
484 
485 	if (pci_read_config_dword(F4, 0x164, &val))
486 		return;
487 
488 	if (val & BIT(2))
489 		return;
490 
491 	on_each_cpu(__fix_erratum_688, NULL, 0);
492 
493 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
494 }
495 
496 static __init int init_amd_nbs(void)
497 {
498 	amd_cache_northbridges();
499 	amd_cache_gart();
500 
501 	fix_erratum_688();
502 
503 	return 0;
504 }
505 
506 /* This has to go after the PCI subsystem */
507 fs_initcall(init_amd_nbs);
508