xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision 113094f7)
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 
25 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
26 static DEFINE_MUTEX(smn_mutex);
27 
28 static u32 *flush_words;
29 
30 static const struct pci_device_id amd_root_ids[] = {
31 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
32 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
33 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
34 	{}
35 };
36 
37 
38 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
39 
40 const struct pci_device_id amd_nb_misc_ids[] = {
41 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
42 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
43 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
44 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
45 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
46 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
47 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
48 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
49 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
50 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
51 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
52 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
53 	{}
54 };
55 EXPORT_SYMBOL_GPL(amd_nb_misc_ids);
56 
57 static const struct pci_device_id amd_nb_link_ids[] = {
58 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
59 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
60 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
61 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
62 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
63 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
64 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
65 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
66 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
67 	{}
68 };
69 
70 static const struct pci_device_id hygon_root_ids[] = {
71 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
72 	{}
73 };
74 
75 static const struct pci_device_id hygon_nb_misc_ids[] = {
76 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
77 	{}
78 };
79 
80 static const struct pci_device_id hygon_nb_link_ids[] = {
81 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
82 	{}
83 };
84 
85 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
86 	{ 0x00, 0x18, 0x20 },
87 	{ 0xff, 0x00, 0x20 },
88 	{ 0xfe, 0x00, 0x20 },
89 	{ }
90 };
91 
92 static struct amd_northbridge_info amd_northbridges;
93 
94 u16 amd_nb_num(void)
95 {
96 	return amd_northbridges.num;
97 }
98 EXPORT_SYMBOL_GPL(amd_nb_num);
99 
100 bool amd_nb_has_feature(unsigned int feature)
101 {
102 	return ((amd_northbridges.flags & feature) == feature);
103 }
104 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
105 
106 struct amd_northbridge *node_to_amd_nb(int node)
107 {
108 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
109 }
110 EXPORT_SYMBOL_GPL(node_to_amd_nb);
111 
112 static struct pci_dev *next_northbridge(struct pci_dev *dev,
113 					const struct pci_device_id *ids)
114 {
115 	do {
116 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
117 		if (!dev)
118 			break;
119 	} while (!pci_match_id(ids, dev));
120 	return dev;
121 }
122 
123 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
124 {
125 	struct pci_dev *root;
126 	int err = -ENODEV;
127 
128 	if (node >= amd_northbridges.num)
129 		goto out;
130 
131 	root = node_to_amd_nb(node)->root;
132 	if (!root)
133 		goto out;
134 
135 	mutex_lock(&smn_mutex);
136 
137 	err = pci_write_config_dword(root, 0x60, address);
138 	if (err) {
139 		pr_warn("Error programming SMN address 0x%x.\n", address);
140 		goto out_unlock;
141 	}
142 
143 	err = (write ? pci_write_config_dword(root, 0x64, *value)
144 		     : pci_read_config_dword(root, 0x64, value));
145 	if (err)
146 		pr_warn("Error %s SMN address 0x%x.\n",
147 			(write ? "writing to" : "reading from"), address);
148 
149 out_unlock:
150 	mutex_unlock(&smn_mutex);
151 
152 out:
153 	return err;
154 }
155 
156 int amd_smn_read(u16 node, u32 address, u32 *value)
157 {
158 	return __amd_smn_rw(node, address, value, false);
159 }
160 EXPORT_SYMBOL_GPL(amd_smn_read);
161 
162 int amd_smn_write(u16 node, u32 address, u32 value)
163 {
164 	return __amd_smn_rw(node, address, &value, true);
165 }
166 EXPORT_SYMBOL_GPL(amd_smn_write);
167 
168 /*
169  * Data Fabric Indirect Access uses FICAA/FICAD.
170  *
171  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
172  * on the device's Instance Id and the PCI function and register offset of
173  * the desired register.
174  *
175  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
176  * and FICAD HI registers but so far we only need the LO register.
177  */
178 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
179 {
180 	struct pci_dev *F4;
181 	u32 ficaa;
182 	int err = -ENODEV;
183 
184 	if (node >= amd_northbridges.num)
185 		goto out;
186 
187 	F4 = node_to_amd_nb(node)->link;
188 	if (!F4)
189 		goto out;
190 
191 	ficaa  = 1;
192 	ficaa |= reg & 0x3FC;
193 	ficaa |= (func & 0x7) << 11;
194 	ficaa |= instance_id << 16;
195 
196 	mutex_lock(&smn_mutex);
197 
198 	err = pci_write_config_dword(F4, 0x5C, ficaa);
199 	if (err) {
200 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
201 		goto out_unlock;
202 	}
203 
204 	err = pci_read_config_dword(F4, 0x98, lo);
205 	if (err)
206 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
207 
208 out_unlock:
209 	mutex_unlock(&smn_mutex);
210 
211 out:
212 	return err;
213 }
214 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
215 
216 int amd_cache_northbridges(void)
217 {
218 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
219 	const struct pci_device_id *link_ids = amd_nb_link_ids;
220 	const struct pci_device_id *root_ids = amd_root_ids;
221 	struct pci_dev *root, *misc, *link;
222 	struct amd_northbridge *nb;
223 	u16 roots_per_misc = 0;
224 	u16 misc_count = 0;
225 	u16 root_count = 0;
226 	u16 i, j;
227 
228 	if (amd_northbridges.num)
229 		return 0;
230 
231 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
232 		root_ids = hygon_root_ids;
233 		misc_ids = hygon_nb_misc_ids;
234 		link_ids = hygon_nb_link_ids;
235 	}
236 
237 	misc = NULL;
238 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
239 		misc_count++;
240 
241 	if (!misc_count)
242 		return -ENODEV;
243 
244 	root = NULL;
245 	while ((root = next_northbridge(root, root_ids)) != NULL)
246 		root_count++;
247 
248 	if (root_count) {
249 		roots_per_misc = root_count / misc_count;
250 
251 		/*
252 		 * There should be _exactly_ N roots for each DF/SMN
253 		 * interface.
254 		 */
255 		if (!roots_per_misc || (root_count % roots_per_misc)) {
256 			pr_info("Unsupported AMD DF/PCI configuration found\n");
257 			return -ENODEV;
258 		}
259 	}
260 
261 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
262 	if (!nb)
263 		return -ENOMEM;
264 
265 	amd_northbridges.nb = nb;
266 	amd_northbridges.num = misc_count;
267 
268 	link = misc = root = NULL;
269 	for (i = 0; i < amd_northbridges.num; i++) {
270 		node_to_amd_nb(i)->root = root =
271 			next_northbridge(root, root_ids);
272 		node_to_amd_nb(i)->misc = misc =
273 			next_northbridge(misc, misc_ids);
274 		node_to_amd_nb(i)->link = link =
275 			next_northbridge(link, link_ids);
276 
277 		/*
278 		 * If there are more PCI root devices than data fabric/
279 		 * system management network interfaces, then the (N)
280 		 * PCI roots per DF/SMN interface are functionally the
281 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
282 		 * PCI roots should be skipped per DF/SMN interface so
283 		 * the following DF/SMN interfaces get mapped to
284 		 * correct PCI roots.
285 		 */
286 		for (j = 1; j < roots_per_misc; j++)
287 			root = next_northbridge(root, root_ids);
288 	}
289 
290 	if (amd_gart_present())
291 		amd_northbridges.flags |= AMD_NB_GART;
292 
293 	/*
294 	 * Check for L3 cache presence.
295 	 */
296 	if (!cpuid_edx(0x80000006))
297 		return 0;
298 
299 	/*
300 	 * Some CPU families support L3 Cache Index Disable. There are some
301 	 * limitations because of E382 and E388 on family 0x10.
302 	 */
303 	if (boot_cpu_data.x86 == 0x10 &&
304 	    boot_cpu_data.x86_model >= 0x8 &&
305 	    (boot_cpu_data.x86_model > 0x9 ||
306 	     boot_cpu_data.x86_stepping >= 0x1))
307 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
308 
309 	if (boot_cpu_data.x86 == 0x15)
310 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
311 
312 	/* L3 cache partitioning is supported on family 0x15 */
313 	if (boot_cpu_data.x86 == 0x15)
314 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
315 
316 	return 0;
317 }
318 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
319 
320 /*
321  * Ignores subdevice/subvendor but as far as I can figure out
322  * they're useless anyways
323  */
324 bool __init early_is_amd_nb(u32 device)
325 {
326 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
327 	const struct pci_device_id *id;
328 	u32 vendor = device & 0xffff;
329 
330 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
331 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
332 		return false;
333 
334 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
335 		misc_ids = hygon_nb_misc_ids;
336 
337 	device >>= 16;
338 	for (id = misc_ids; id->vendor; id++)
339 		if (vendor == id->vendor && device == id->device)
340 			return true;
341 	return false;
342 }
343 
344 struct resource *amd_get_mmconfig_range(struct resource *res)
345 {
346 	u32 address;
347 	u64 base, msr;
348 	unsigned int segn_busn_bits;
349 
350 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
351 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
352 		return NULL;
353 
354 	/* assume all cpus from fam10h have mmconfig */
355 	if (boot_cpu_data.x86 < 0x10)
356 		return NULL;
357 
358 	address = MSR_FAM10H_MMIO_CONF_BASE;
359 	rdmsrl(address, msr);
360 
361 	/* mmconfig is not enabled */
362 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
363 		return NULL;
364 
365 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
366 
367 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
368 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
369 
370 	res->flags = IORESOURCE_MEM;
371 	res->start = base;
372 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
373 	return res;
374 }
375 
376 int amd_get_subcaches(int cpu)
377 {
378 	struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
379 	unsigned int mask;
380 
381 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
382 		return 0;
383 
384 	pci_read_config_dword(link, 0x1d4, &mask);
385 
386 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
387 }
388 
389 int amd_set_subcaches(int cpu, unsigned long mask)
390 {
391 	static unsigned int reset, ban;
392 	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));
393 	unsigned int reg;
394 	int cuid;
395 
396 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
397 		return -EINVAL;
398 
399 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
400 	if (reset == 0) {
401 		pci_read_config_dword(nb->link, 0x1d4, &reset);
402 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
403 		ban &= 0x180000;
404 	}
405 
406 	/* deactivate BAN mode if any subcaches are to be disabled */
407 	if (mask != 0xf) {
408 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
409 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
410 	}
411 
412 	cuid = cpu_data(cpu).cpu_core_id;
413 	mask <<= 4 * cuid;
414 	mask |= (0xf ^ (1 << cuid)) << 26;
415 
416 	pci_write_config_dword(nb->link, 0x1d4, mask);
417 
418 	/* reset BAN mode if L3 partitioning returned to reset state */
419 	pci_read_config_dword(nb->link, 0x1d4, &reg);
420 	if (reg == reset) {
421 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
422 		reg &= ~0x180000;
423 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
424 	}
425 
426 	return 0;
427 }
428 
429 static void amd_cache_gart(void)
430 {
431 	u16 i;
432 
433 	if (!amd_nb_has_feature(AMD_NB_GART))
434 		return;
435 
436 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
437 	if (!flush_words) {
438 		amd_northbridges.flags &= ~AMD_NB_GART;
439 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
440 		return;
441 	}
442 
443 	for (i = 0; i != amd_northbridges.num; i++)
444 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
445 }
446 
447 void amd_flush_garts(void)
448 {
449 	int flushed, i;
450 	unsigned long flags;
451 	static DEFINE_SPINLOCK(gart_lock);
452 
453 	if (!amd_nb_has_feature(AMD_NB_GART))
454 		return;
455 
456 	/*
457 	 * Avoid races between AGP and IOMMU. In theory it's not needed
458 	 * but I'm not sure if the hardware won't lose flush requests
459 	 * when another is pending. This whole thing is so expensive anyways
460 	 * that it doesn't matter to serialize more. -AK
461 	 */
462 	spin_lock_irqsave(&gart_lock, flags);
463 	flushed = 0;
464 	for (i = 0; i < amd_northbridges.num; i++) {
465 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
466 				       flush_words[i] | 1);
467 		flushed++;
468 	}
469 	for (i = 0; i < amd_northbridges.num; i++) {
470 		u32 w;
471 		/* Make sure the hardware actually executed the flush*/
472 		for (;;) {
473 			pci_read_config_dword(node_to_amd_nb(i)->misc,
474 					      0x9c, &w);
475 			if (!(w & 1))
476 				break;
477 			cpu_relax();
478 		}
479 	}
480 	spin_unlock_irqrestore(&gart_lock, flags);
481 	if (!flushed)
482 		pr_notice("nothing to flush?\n");
483 }
484 EXPORT_SYMBOL_GPL(amd_flush_garts);
485 
486 static void __fix_erratum_688(void *info)
487 {
488 #define MSR_AMD64_IC_CFG 0xC0011021
489 
490 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
491 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
492 }
493 
494 /* Apply erratum 688 fix so machines without a BIOS fix work. */
495 static __init void fix_erratum_688(void)
496 {
497 	struct pci_dev *F4;
498 	u32 val;
499 
500 	if (boot_cpu_data.x86 != 0x14)
501 		return;
502 
503 	if (!amd_northbridges.num)
504 		return;
505 
506 	F4 = node_to_amd_nb(0)->link;
507 	if (!F4)
508 		return;
509 
510 	if (pci_read_config_dword(F4, 0x164, &val))
511 		return;
512 
513 	if (val & BIT(2))
514 		return;
515 
516 	on_each_cpu(__fix_erratum_688, NULL, 0);
517 
518 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
519 }
520 
521 static __init int init_amd_nbs(void)
522 {
523 	amd_cache_northbridges();
524 	amd_cache_gart();
525 
526 	fix_erratum_688();
527 
528 	return 0;
529 }
530 
531 /* This has to go after the PCI subsystem */
532 fs_initcall(init_amd_nbs);
533