xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision d0e22329)
1 /*
2  * Shared support code for AMD K8 northbridges and derivates.
3  * Copyright 2006 Andi Kleen, SUSE Labs. Subject to GPLv2.
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/types.h>
9 #include <linux/slab.h>
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/export.h>
13 #include <linux/spinlock.h>
14 #include <linux/pci_ids.h>
15 #include <asm/amd_nb.h>
16 
17 #define PCI_DEVICE_ID_AMD_17H_ROOT	0x1450
18 #define PCI_DEVICE_ID_AMD_17H_M10H_ROOT	0x15d0
19 #define PCI_DEVICE_ID_AMD_17H_M30H_ROOT	0x1480
20 #define PCI_DEVICE_ID_AMD_17H_DF_F4	0x1464
21 #define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
22 #define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
23 
24 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
25 static DEFINE_MUTEX(smn_mutex);
26 
27 static u32 *flush_words;
28 
29 static const struct pci_device_id amd_root_ids[] = {
30 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
31 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
32 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
33 	{}
34 };
35 
36 
37 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
38 
39 const struct pci_device_id amd_nb_misc_ids[] = {
40 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
41 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
42 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
43 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
44 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
45 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
46 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
47 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
48 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
49 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
50 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
51 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
52 	{}
53 };
54 EXPORT_SYMBOL_GPL(amd_nb_misc_ids);
55 
56 static const struct pci_device_id amd_nb_link_ids[] = {
57 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
58 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
59 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
60 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
61 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
62 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
63 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
64 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
65 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
66 	{}
67 };
68 
69 static const struct pci_device_id hygon_root_ids[] = {
70 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
71 	{}
72 };
73 
74 const struct pci_device_id hygon_nb_misc_ids[] = {
75 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
76 	{}
77 };
78 
79 static const struct pci_device_id hygon_nb_link_ids[] = {
80 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
81 	{}
82 };
83 
84 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
85 	{ 0x00, 0x18, 0x20 },
86 	{ 0xff, 0x00, 0x20 },
87 	{ 0xfe, 0x00, 0x20 },
88 	{ }
89 };
90 
91 static struct amd_northbridge_info amd_northbridges;
92 
93 u16 amd_nb_num(void)
94 {
95 	return amd_northbridges.num;
96 }
97 EXPORT_SYMBOL_GPL(amd_nb_num);
98 
99 bool amd_nb_has_feature(unsigned int feature)
100 {
101 	return ((amd_northbridges.flags & feature) == feature);
102 }
103 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
104 
105 struct amd_northbridge *node_to_amd_nb(int node)
106 {
107 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
108 }
109 EXPORT_SYMBOL_GPL(node_to_amd_nb);
110 
111 static struct pci_dev *next_northbridge(struct pci_dev *dev,
112 					const struct pci_device_id *ids)
113 {
114 	do {
115 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
116 		if (!dev)
117 			break;
118 	} while (!pci_match_id(ids, dev));
119 	return dev;
120 }
121 
122 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
123 {
124 	struct pci_dev *root;
125 	int err = -ENODEV;
126 
127 	if (node >= amd_northbridges.num)
128 		goto out;
129 
130 	root = node_to_amd_nb(node)->root;
131 	if (!root)
132 		goto out;
133 
134 	mutex_lock(&smn_mutex);
135 
136 	err = pci_write_config_dword(root, 0x60, address);
137 	if (err) {
138 		pr_warn("Error programming SMN address 0x%x.\n", address);
139 		goto out_unlock;
140 	}
141 
142 	err = (write ? pci_write_config_dword(root, 0x64, *value)
143 		     : pci_read_config_dword(root, 0x64, value));
144 	if (err)
145 		pr_warn("Error %s SMN address 0x%x.\n",
146 			(write ? "writing to" : "reading from"), address);
147 
148 out_unlock:
149 	mutex_unlock(&smn_mutex);
150 
151 out:
152 	return err;
153 }
154 
155 int amd_smn_read(u16 node, u32 address, u32 *value)
156 {
157 	return __amd_smn_rw(node, address, value, false);
158 }
159 EXPORT_SYMBOL_GPL(amd_smn_read);
160 
161 int amd_smn_write(u16 node, u32 address, u32 value)
162 {
163 	return __amd_smn_rw(node, address, &value, true);
164 }
165 EXPORT_SYMBOL_GPL(amd_smn_write);
166 
167 /*
168  * Data Fabric Indirect Access uses FICAA/FICAD.
169  *
170  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
171  * on the device's Instance Id and the PCI function and register offset of
172  * the desired register.
173  *
174  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
175  * and FICAD HI registers but so far we only need the LO register.
176  */
177 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
178 {
179 	struct pci_dev *F4;
180 	u32 ficaa;
181 	int err = -ENODEV;
182 
183 	if (node >= amd_northbridges.num)
184 		goto out;
185 
186 	F4 = node_to_amd_nb(node)->link;
187 	if (!F4)
188 		goto out;
189 
190 	ficaa  = 1;
191 	ficaa |= reg & 0x3FC;
192 	ficaa |= (func & 0x7) << 11;
193 	ficaa |= instance_id << 16;
194 
195 	mutex_lock(&smn_mutex);
196 
197 	err = pci_write_config_dword(F4, 0x5C, ficaa);
198 	if (err) {
199 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
200 		goto out_unlock;
201 	}
202 
203 	err = pci_read_config_dword(F4, 0x98, lo);
204 	if (err)
205 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
206 
207 out_unlock:
208 	mutex_unlock(&smn_mutex);
209 
210 out:
211 	return err;
212 }
213 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
214 
215 int amd_cache_northbridges(void)
216 {
217 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
218 	const struct pci_device_id *link_ids = amd_nb_link_ids;
219 	const struct pci_device_id *root_ids = amd_root_ids;
220 	struct pci_dev *root, *misc, *link;
221 	struct amd_northbridge *nb;
222 	u16 roots_per_misc = 0;
223 	u16 misc_count = 0;
224 	u16 root_count = 0;
225 	u16 i, j;
226 
227 	if (amd_northbridges.num)
228 		return 0;
229 
230 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
231 		root_ids = hygon_root_ids;
232 		misc_ids = hygon_nb_misc_ids;
233 		link_ids = hygon_nb_link_ids;
234 	}
235 
236 	misc = NULL;
237 	while ((misc = next_northbridge(misc, misc_ids)) != NULL)
238 		misc_count++;
239 
240 	if (!misc_count)
241 		return -ENODEV;
242 
243 	root = NULL;
244 	while ((root = next_northbridge(root, root_ids)) != NULL)
245 		root_count++;
246 
247 	if (root_count) {
248 		roots_per_misc = root_count / misc_count;
249 
250 		/*
251 		 * There should be _exactly_ N roots for each DF/SMN
252 		 * interface.
253 		 */
254 		if (!roots_per_misc || (root_count % roots_per_misc)) {
255 			pr_info("Unsupported AMD DF/PCI configuration found\n");
256 			return -ENODEV;
257 		}
258 	}
259 
260 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
261 	if (!nb)
262 		return -ENOMEM;
263 
264 	amd_northbridges.nb = nb;
265 	amd_northbridges.num = misc_count;
266 
267 	link = misc = root = NULL;
268 	for (i = 0; i < amd_northbridges.num; i++) {
269 		node_to_amd_nb(i)->root = root =
270 			next_northbridge(root, root_ids);
271 		node_to_amd_nb(i)->misc = misc =
272 			next_northbridge(misc, misc_ids);
273 		node_to_amd_nb(i)->link = link =
274 			next_northbridge(link, link_ids);
275 
276 		/*
277 		 * If there are more PCI root devices than data fabric/
278 		 * system management network interfaces, then the (N)
279 		 * PCI roots per DF/SMN interface are functionally the
280 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
281 		 * PCI roots should be skipped per DF/SMN interface so
282 		 * the following DF/SMN interfaces get mapped to
283 		 * correct PCI roots.
284 		 */
285 		for (j = 1; j < roots_per_misc; j++)
286 			root = next_northbridge(root, root_ids);
287 	}
288 
289 	if (amd_gart_present())
290 		amd_northbridges.flags |= AMD_NB_GART;
291 
292 	/*
293 	 * Check for L3 cache presence.
294 	 */
295 	if (!cpuid_edx(0x80000006))
296 		return 0;
297 
298 	/*
299 	 * Some CPU families support L3 Cache Index Disable. There are some
300 	 * limitations because of E382 and E388 on family 0x10.
301 	 */
302 	if (boot_cpu_data.x86 == 0x10 &&
303 	    boot_cpu_data.x86_model >= 0x8 &&
304 	    (boot_cpu_data.x86_model > 0x9 ||
305 	     boot_cpu_data.x86_stepping >= 0x1))
306 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
307 
308 	if (boot_cpu_data.x86 == 0x15)
309 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
310 
311 	/* L3 cache partitioning is supported on family 0x15 */
312 	if (boot_cpu_data.x86 == 0x15)
313 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
314 
315 	return 0;
316 }
317 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
318 
319 /*
320  * Ignores subdevice/subvendor but as far as I can figure out
321  * they're useless anyways
322  */
323 bool __init early_is_amd_nb(u32 device)
324 {
325 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
326 	const struct pci_device_id *id;
327 	u32 vendor = device & 0xffff;
328 
329 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
330 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
331 		return false;
332 
333 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
334 		misc_ids = hygon_nb_misc_ids;
335 
336 	device >>= 16;
337 	for (id = misc_ids; id->vendor; id++)
338 		if (vendor == id->vendor && device == id->device)
339 			return true;
340 	return false;
341 }
342 
343 struct resource *amd_get_mmconfig_range(struct resource *res)
344 {
345 	u32 address;
346 	u64 base, msr;
347 	unsigned int segn_busn_bits;
348 
349 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
350 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
351 		return NULL;
352 
353 	/* assume all cpus from fam10h have mmconfig */
354 	if (boot_cpu_data.x86 < 0x10)
355 		return NULL;
356 
357 	address = MSR_FAM10H_MMIO_CONF_BASE;
358 	rdmsrl(address, msr);
359 
360 	/* mmconfig is not enabled */
361 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
362 		return NULL;
363 
364 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
365 
366 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
367 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
368 
369 	res->flags = IORESOURCE_MEM;
370 	res->start = base;
371 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
372 	return res;
373 }
374 
375 int amd_get_subcaches(int cpu)
376 {
377 	struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
378 	unsigned int mask;
379 
380 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
381 		return 0;
382 
383 	pci_read_config_dword(link, 0x1d4, &mask);
384 
385 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
386 }
387 
388 int amd_set_subcaches(int cpu, unsigned long mask)
389 {
390 	static unsigned int reset, ban;
391 	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));
392 	unsigned int reg;
393 	int cuid;
394 
395 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
396 		return -EINVAL;
397 
398 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
399 	if (reset == 0) {
400 		pci_read_config_dword(nb->link, 0x1d4, &reset);
401 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
402 		ban &= 0x180000;
403 	}
404 
405 	/* deactivate BAN mode if any subcaches are to be disabled */
406 	if (mask != 0xf) {
407 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
408 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
409 	}
410 
411 	cuid = cpu_data(cpu).cpu_core_id;
412 	mask <<= 4 * cuid;
413 	mask |= (0xf ^ (1 << cuid)) << 26;
414 
415 	pci_write_config_dword(nb->link, 0x1d4, mask);
416 
417 	/* reset BAN mode if L3 partitioning returned to reset state */
418 	pci_read_config_dword(nb->link, 0x1d4, &reg);
419 	if (reg == reset) {
420 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
421 		reg &= ~0x180000;
422 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
423 	}
424 
425 	return 0;
426 }
427 
428 static void amd_cache_gart(void)
429 {
430 	u16 i;
431 
432 	if (!amd_nb_has_feature(AMD_NB_GART))
433 		return;
434 
435 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
436 	if (!flush_words) {
437 		amd_northbridges.flags &= ~AMD_NB_GART;
438 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
439 		return;
440 	}
441 
442 	for (i = 0; i != amd_northbridges.num; i++)
443 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
444 }
445 
446 void amd_flush_garts(void)
447 {
448 	int flushed, i;
449 	unsigned long flags;
450 	static DEFINE_SPINLOCK(gart_lock);
451 
452 	if (!amd_nb_has_feature(AMD_NB_GART))
453 		return;
454 
455 	/*
456 	 * Avoid races between AGP and IOMMU. In theory it's not needed
457 	 * but I'm not sure if the hardware won't lose flush requests
458 	 * when another is pending. This whole thing is so expensive anyways
459 	 * that it doesn't matter to serialize more. -AK
460 	 */
461 	spin_lock_irqsave(&gart_lock, flags);
462 	flushed = 0;
463 	for (i = 0; i < amd_northbridges.num; i++) {
464 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
465 				       flush_words[i] | 1);
466 		flushed++;
467 	}
468 	for (i = 0; i < amd_northbridges.num; i++) {
469 		u32 w;
470 		/* Make sure the hardware actually executed the flush*/
471 		for (;;) {
472 			pci_read_config_dword(node_to_amd_nb(i)->misc,
473 					      0x9c, &w);
474 			if (!(w & 1))
475 				break;
476 			cpu_relax();
477 		}
478 	}
479 	spin_unlock_irqrestore(&gart_lock, flags);
480 	if (!flushed)
481 		pr_notice("nothing to flush?\n");
482 }
483 EXPORT_SYMBOL_GPL(amd_flush_garts);
484 
485 static void __fix_erratum_688(void *info)
486 {
487 #define MSR_AMD64_IC_CFG 0xC0011021
488 
489 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
490 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
491 }
492 
493 /* Apply erratum 688 fix so machines without a BIOS fix work. */
494 static __init void fix_erratum_688(void)
495 {
496 	struct pci_dev *F4;
497 	u32 val;
498 
499 	if (boot_cpu_data.x86 != 0x14)
500 		return;
501 
502 	if (!amd_northbridges.num)
503 		return;
504 
505 	F4 = node_to_amd_nb(0)->link;
506 	if (!F4)
507 		return;
508 
509 	if (pci_read_config_dword(F4, 0x164, &val))
510 		return;
511 
512 	if (val & BIT(2))
513 		return;
514 
515 	on_each_cpu(__fix_erratum_688, NULL, 0);
516 
517 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
518 }
519 
520 static __init int init_amd_nbs(void)
521 {
522 	amd_cache_northbridges();
523 	amd_cache_gart();
524 
525 	fix_erratum_688();
526 
527 	return 0;
528 }
529 
530 /* This has to go after the PCI subsystem */
531 fs_initcall(init_amd_nbs);
532