xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision 08283d30)
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 
26 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
27 static DEFINE_MUTEX(smn_mutex);
28 
29 static u32 *flush_words;
30 
31 static const struct pci_device_id amd_root_ids[] = {
32 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
33 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
34 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
35 	{}
36 };
37 
38 
39 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
40 
41 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 	{}
56 };
57 EXPORT_SYMBOL_GPL(amd_nb_misc_ids);
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_CNB17H_F4) },
70 	{}
71 };
72 
73 static const struct pci_device_id hygon_root_ids[] = {
74 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
75 	{}
76 };
77 
78 static const struct pci_device_id hygon_nb_misc_ids[] = {
79 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
80 	{}
81 };
82 
83 static const struct pci_device_id hygon_nb_link_ids[] = {
84 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
85 	{}
86 };
87 
88 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
89 	{ 0x00, 0x18, 0x20 },
90 	{ 0xff, 0x00, 0x20 },
91 	{ 0xfe, 0x00, 0x20 },
92 	{ }
93 };
94 
95 static struct amd_northbridge_info amd_northbridges;
96 
97 u16 amd_nb_num(void)
98 {
99 	return amd_northbridges.num;
100 }
101 EXPORT_SYMBOL_GPL(amd_nb_num);
102 
103 bool amd_nb_has_feature(unsigned int feature)
104 {
105 	return ((amd_northbridges.flags & feature) == feature);
106 }
107 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
108 
109 struct amd_northbridge *node_to_amd_nb(int node)
110 {
111 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
112 }
113 EXPORT_SYMBOL_GPL(node_to_amd_nb);
114 
115 static struct pci_dev *next_northbridge(struct pci_dev *dev,
116 					const struct pci_device_id *ids)
117 {
118 	do {
119 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
120 		if (!dev)
121 			break;
122 	} while (!pci_match_id(ids, dev));
123 	return dev;
124 }
125 
126 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
127 {
128 	struct pci_dev *root;
129 	int err = -ENODEV;
130 
131 	if (node >= amd_northbridges.num)
132 		goto out;
133 
134 	root = node_to_amd_nb(node)->root;
135 	if (!root)
136 		goto out;
137 
138 	mutex_lock(&smn_mutex);
139 
140 	err = pci_write_config_dword(root, 0x60, address);
141 	if (err) {
142 		pr_warn("Error programming SMN address 0x%x.\n", address);
143 		goto out_unlock;
144 	}
145 
146 	err = (write ? pci_write_config_dword(root, 0x64, *value)
147 		     : pci_read_config_dword(root, 0x64, value));
148 	if (err)
149 		pr_warn("Error %s SMN address 0x%x.\n",
150 			(write ? "writing to" : "reading from"), address);
151 
152 out_unlock:
153 	mutex_unlock(&smn_mutex);
154 
155 out:
156 	return err;
157 }
158 
159 int amd_smn_read(u16 node, u32 address, u32 *value)
160 {
161 	return __amd_smn_rw(node, address, value, false);
162 }
163 EXPORT_SYMBOL_GPL(amd_smn_read);
164 
165 int amd_smn_write(u16 node, u32 address, u32 value)
166 {
167 	return __amd_smn_rw(node, address, &value, true);
168 }
169 EXPORT_SYMBOL_GPL(amd_smn_write);
170 
171 /*
172  * Data Fabric Indirect Access uses FICAA/FICAD.
173  *
174  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
175  * on the device's Instance Id and the PCI function and register offset of
176  * the desired register.
177  *
178  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
179  * and FICAD HI registers but so far we only need the LO register.
180  */
181 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
182 {
183 	struct pci_dev *F4;
184 	u32 ficaa;
185 	int err = -ENODEV;
186 
187 	if (node >= amd_northbridges.num)
188 		goto out;
189 
190 	F4 = node_to_amd_nb(node)->link;
191 	if (!F4)
192 		goto out;
193 
194 	ficaa  = 1;
195 	ficaa |= reg & 0x3FC;
196 	ficaa |= (func & 0x7) << 11;
197 	ficaa |= instance_id << 16;
198 
199 	mutex_lock(&smn_mutex);
200 
201 	err = pci_write_config_dword(F4, 0x5C, ficaa);
202 	if (err) {
203 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
204 		goto out_unlock;
205 	}
206 
207 	err = pci_read_config_dword(F4, 0x98, lo);
208 	if (err)
209 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
210 
211 out_unlock:
212 	mutex_unlock(&smn_mutex);
213 
214 out:
215 	return err;
216 }
217 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
218 
219 int amd_cache_northbridges(void)
220 {
221 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
222 	const struct pci_device_id *link_ids = amd_nb_link_ids;
223 	const struct pci_device_id *root_ids = amd_root_ids;
224 	struct pci_dev *root, *misc, *link;
225 	struct amd_northbridge *nb;
226 	u16 roots_per_misc = 0;
227 	u16 misc_count = 0;
228 	u16 root_count = 0;
229 	u16 i, j;
230 
231 	if (amd_northbridges.num)
232 		return 0;
233 
234 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
235 		root_ids = hygon_root_ids;
236 		misc_ids = hygon_nb_misc_ids;
237 		link_ids = hygon_nb_link_ids;
238 	}
239 
240 	misc = NULL;
241 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
242 		misc_count++;
243 
244 	if (!misc_count)
245 		return -ENODEV;
246 
247 	root = NULL;
248 	while ((root = next_northbridge(root, root_ids)) != NULL)
249 		root_count++;
250 
251 	if (root_count) {
252 		roots_per_misc = root_count / misc_count;
253 
254 		/*
255 		 * There should be _exactly_ N roots for each DF/SMN
256 		 * interface.
257 		 */
258 		if (!roots_per_misc || (root_count % roots_per_misc)) {
259 			pr_info("Unsupported AMD DF/PCI configuration found\n");
260 			return -ENODEV;
261 		}
262 	}
263 
264 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
265 	if (!nb)
266 		return -ENOMEM;
267 
268 	amd_northbridges.nb = nb;
269 	amd_northbridges.num = misc_count;
270 
271 	link = misc = root = NULL;
272 	for (i = 0; i < amd_northbridges.num; i++) {
273 		node_to_amd_nb(i)->root = root =
274 			next_northbridge(root, root_ids);
275 		node_to_amd_nb(i)->misc = misc =
276 			next_northbridge(misc, misc_ids);
277 		node_to_amd_nb(i)->link = link =
278 			next_northbridge(link, link_ids);
279 
280 		/*
281 		 * If there are more PCI root devices than data fabric/
282 		 * system management network interfaces, then the (N)
283 		 * PCI roots per DF/SMN interface are functionally the
284 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
285 		 * PCI roots should be skipped per DF/SMN interface so
286 		 * the following DF/SMN interfaces get mapped to
287 		 * correct PCI roots.
288 		 */
289 		for (j = 1; j < roots_per_misc; j++)
290 			root = next_northbridge(root, root_ids);
291 	}
292 
293 	if (amd_gart_present())
294 		amd_northbridges.flags |= AMD_NB_GART;
295 
296 	/*
297 	 * Check for L3 cache presence.
298 	 */
299 	if (!cpuid_edx(0x80000006))
300 		return 0;
301 
302 	/*
303 	 * Some CPU families support L3 Cache Index Disable. There are some
304 	 * limitations because of E382 and E388 on family 0x10.
305 	 */
306 	if (boot_cpu_data.x86 == 0x10 &&
307 	    boot_cpu_data.x86_model >= 0x8 &&
308 	    (boot_cpu_data.x86_model > 0x9 ||
309 	     boot_cpu_data.x86_stepping >= 0x1))
310 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
311 
312 	if (boot_cpu_data.x86 == 0x15)
313 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
314 
315 	/* L3 cache partitioning is supported on family 0x15 */
316 	if (boot_cpu_data.x86 == 0x15)
317 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
318 
319 	return 0;
320 }
321 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
322 
323 /*
324  * Ignores subdevice/subvendor but as far as I can figure out
325  * they're useless anyways
326  */
327 bool __init early_is_amd_nb(u32 device)
328 {
329 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
330 	const struct pci_device_id *id;
331 	u32 vendor = device & 0xffff;
332 
333 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
334 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
335 		return false;
336 
337 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
338 		misc_ids = hygon_nb_misc_ids;
339 
340 	device >>= 16;
341 	for (id = misc_ids; id->vendor; id++)
342 		if (vendor == id->vendor && device == id->device)
343 			return true;
344 	return false;
345 }
346 
347 struct resource *amd_get_mmconfig_range(struct resource *res)
348 {
349 	u32 address;
350 	u64 base, msr;
351 	unsigned int segn_busn_bits;
352 
353 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
354 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
355 		return NULL;
356 
357 	/* assume all cpus from fam10h have mmconfig */
358 	if (boot_cpu_data.x86 < 0x10)
359 		return NULL;
360 
361 	address = MSR_FAM10H_MMIO_CONF_BASE;
362 	rdmsrl(address, msr);
363 
364 	/* mmconfig is not enabled */
365 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
366 		return NULL;
367 
368 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
369 
370 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
371 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
372 
373 	res->flags = IORESOURCE_MEM;
374 	res->start = base;
375 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
376 	return res;
377 }
378 
379 int amd_get_subcaches(int cpu)
380 {
381 	struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
382 	unsigned int mask;
383 
384 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
385 		return 0;
386 
387 	pci_read_config_dword(link, 0x1d4, &mask);
388 
389 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
390 }
391 
392 int amd_set_subcaches(int cpu, unsigned long mask)
393 {
394 	static unsigned int reset, ban;
395 	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));
396 	unsigned int reg;
397 	int cuid;
398 
399 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
400 		return -EINVAL;
401 
402 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
403 	if (reset == 0) {
404 		pci_read_config_dword(nb->link, 0x1d4, &reset);
405 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
406 		ban &= 0x180000;
407 	}
408 
409 	/* deactivate BAN mode if any subcaches are to be disabled */
410 	if (mask != 0xf) {
411 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
412 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
413 	}
414 
415 	cuid = cpu_data(cpu).cpu_core_id;
416 	mask <<= 4 * cuid;
417 	mask |= (0xf ^ (1 << cuid)) << 26;
418 
419 	pci_write_config_dword(nb->link, 0x1d4, mask);
420 
421 	/* reset BAN mode if L3 partitioning returned to reset state */
422 	pci_read_config_dword(nb->link, 0x1d4, &reg);
423 	if (reg == reset) {
424 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
425 		reg &= ~0x180000;
426 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
427 	}
428 
429 	return 0;
430 }
431 
432 static void amd_cache_gart(void)
433 {
434 	u16 i;
435 
436 	if (!amd_nb_has_feature(AMD_NB_GART))
437 		return;
438 
439 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
440 	if (!flush_words) {
441 		amd_northbridges.flags &= ~AMD_NB_GART;
442 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
443 		return;
444 	}
445 
446 	for (i = 0; i != amd_northbridges.num; i++)
447 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
448 }
449 
450 void amd_flush_garts(void)
451 {
452 	int flushed, i;
453 	unsigned long flags;
454 	static DEFINE_SPINLOCK(gart_lock);
455 
456 	if (!amd_nb_has_feature(AMD_NB_GART))
457 		return;
458 
459 	/*
460 	 * Avoid races between AGP and IOMMU. In theory it's not needed
461 	 * but I'm not sure if the hardware won't lose flush requests
462 	 * when another is pending. This whole thing is so expensive anyways
463 	 * that it doesn't matter to serialize more. -AK
464 	 */
465 	spin_lock_irqsave(&gart_lock, flags);
466 	flushed = 0;
467 	for (i = 0; i < amd_northbridges.num; i++) {
468 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
469 				       flush_words[i] | 1);
470 		flushed++;
471 	}
472 	for (i = 0; i < amd_northbridges.num; i++) {
473 		u32 w;
474 		/* Make sure the hardware actually executed the flush*/
475 		for (;;) {
476 			pci_read_config_dword(node_to_amd_nb(i)->misc,
477 					      0x9c, &w);
478 			if (!(w & 1))
479 				break;
480 			cpu_relax();
481 		}
482 	}
483 	spin_unlock_irqrestore(&gart_lock, flags);
484 	if (!flushed)
485 		pr_notice("nothing to flush?\n");
486 }
487 EXPORT_SYMBOL_GPL(amd_flush_garts);
488 
489 static void __fix_erratum_688(void *info)
490 {
491 #define MSR_AMD64_IC_CFG 0xC0011021
492 
493 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
494 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
495 }
496 
497 /* Apply erratum 688 fix so machines without a BIOS fix work. */
498 static __init void fix_erratum_688(void)
499 {
500 	struct pci_dev *F4;
501 	u32 val;
502 
503 	if (boot_cpu_data.x86 != 0x14)
504 		return;
505 
506 	if (!amd_northbridges.num)
507 		return;
508 
509 	F4 = node_to_amd_nb(0)->link;
510 	if (!F4)
511 		return;
512 
513 	if (pci_read_config_dword(F4, 0x164, &val))
514 		return;
515 
516 	if (val & BIT(2))
517 		return;
518 
519 	on_each_cpu(__fix_erratum_688, NULL, 0);
520 
521 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
522 }
523 
524 static __init int init_amd_nbs(void)
525 {
526 	amd_cache_northbridges();
527 	amd_cache_gart();
528 
529 	fix_erratum_688();
530 
531 	return 0;
532 }
533 
534 /* This has to go after the PCI subsystem */
535 fs_initcall(init_amd_nbs);
536