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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_17H_MA0H_ROOT 0x14b5
23#define PCI_DEVICE_ID_AMD_19H_M10H_ROOT 0x14a4
24#define PCI_DEVICE_ID_AMD_19H_M40H_ROOT 0x14b5
25#define PCI_DEVICE_ID_AMD_19H_M60H_ROOT 0x14d8
26#define PCI_DEVICE_ID_AMD_19H_M70H_ROOT 0x14e8
27#define PCI_DEVICE_ID_AMD_1AH_M00H_ROOT 0x153a
28#define PCI_DEVICE_ID_AMD_1AH_M20H_ROOT 0x1507
29#define PCI_DEVICE_ID_AMD_MI200_ROOT 0x14bb
30#define PCI_DEVICE_ID_AMD_MI300_ROOT 0x14f8
31
32#define PCI_DEVICE_ID_AMD_17H_DF_F4 0x1464
33#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
34#define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
35#define PCI_DEVICE_ID_AMD_17H_M60H_DF_F4 0x144c
36#define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4 0x1444
37#define PCI_DEVICE_ID_AMD_17H_MA0H_DF_F4 0x1728
38#define PCI_DEVICE_ID_AMD_19H_DF_F4 0x1654
39#define PCI_DEVICE_ID_AMD_19H_M10H_DF_F4 0x14b1
40#define PCI_DEVICE_ID_AMD_19H_M40H_DF_F4 0x167d
41#define PCI_DEVICE_ID_AMD_19H_M50H_DF_F4 0x166e
42#define PCI_DEVICE_ID_AMD_19H_M60H_DF_F4 0x14e4
43#define PCI_DEVICE_ID_AMD_19H_M70H_DF_F4 0x14f4
44#define PCI_DEVICE_ID_AMD_19H_M78H_DF_F4 0x12fc
45#define PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4 0x12c4
46#define PCI_DEVICE_ID_AMD_MI200_DF_F4 0x14d4
47#define PCI_DEVICE_ID_AMD_MI300_DF_F4 0x152c
48
49/* Protect the PCI config register pairs used for SMN. */
50static DEFINE_MUTEX(smn_mutex);
51
52static u32 *flush_words;
53
54static const struct pci_device_id amd_root_ids[] = {
55 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
56 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
57 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
58 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_ROOT) },
59 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_ROOT) },
60 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_ROOT) },
61 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_ROOT) },
62 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_ROOT) },
63 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_ROOT) },
64 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_ROOT) },
65 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_ROOT) },
66 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_ROOT) },
67 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_ROOT) },
68 {}
69};
70
71#define PCI_DEVICE_ID_AMD_CNB17H_F4 0x1704
72
73static const struct pci_device_id amd_nb_misc_ids[] = {
74 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
75 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
76 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
77 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
78 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
79 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
80 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
81 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
82 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
83 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
84 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
85 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F3) },
86 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_DF_F3) },
87 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
88 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
89 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
90 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F3) },
91 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F3) },
92 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F3) },
93 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_DF_F3) },
94 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_DF_F3) },
95 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M78H_DF_F3) },
96 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F3) },
97 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_DF_F3) },
98 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F3) },
99 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_DF_F3) },
100 {}
101};
102
103static const struct pci_device_id amd_nb_link_ids[] = {
104 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
105 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
106 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
107 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
108 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
109 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
110 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
111 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
112 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
113 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
114 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_DF_F4) },
115 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
116 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F4) },
117 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F4) },
118 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
119 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_DF_F4) },
120 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_DF_F4) },
121 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M78H_DF_F4) },
122 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
123 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4) },
124 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F4) },
125 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_DF_F4) },
126 {}
127};
128
129static const struct pci_device_id hygon_root_ids[] = {
130 { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
131 {}
132};
133
134static const struct pci_device_id hygon_nb_misc_ids[] = {
135 { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
136 {}
137};
138
139static const struct pci_device_id hygon_nb_link_ids[] = {
140 { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
141 {}
142};
143
144const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
145 { 0x00, 0x18, 0x20 },
146 { 0xff, 0x00, 0x20 },
147 { 0xfe, 0x00, 0x20 },
148 { }
149};
150
151static struct amd_northbridge_info amd_northbridges;
152
153u16 amd_nb_num(void)
154{
155 return amd_northbridges.num;
156}
157EXPORT_SYMBOL_GPL(amd_nb_num);
158
159bool amd_nb_has_feature(unsigned int feature)
160{
161 return ((amd_northbridges.flags & feature) == feature);
162}
163EXPORT_SYMBOL_GPL(amd_nb_has_feature);
164
165struct amd_northbridge *node_to_amd_nb(int node)
166{
167 return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
168}
169EXPORT_SYMBOL_GPL(node_to_amd_nb);
170
171static struct pci_dev *next_northbridge(struct pci_dev *dev,
172 const struct pci_device_id *ids)
173{
174 do {
175 dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
176 if (!dev)
177 break;
178 } while (!pci_match_id(ids, dev));
179 return dev;
180}
181
182static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
183{
184 struct pci_dev *root;
185 int err = -ENODEV;
186
187 if (node >= amd_northbridges.num)
188 goto out;
189
190 root = node_to_amd_nb(node)->root;
191 if (!root)
192 goto out;
193
194 mutex_lock(&smn_mutex);
195
196 err = pci_write_config_dword(root, 0x60, address);
197 if (err) {
198 pr_warn("Error programming SMN address 0x%x.\n", address);
199 goto out_unlock;
200 }
201
202 err = (write ? pci_write_config_dword(root, 0x64, *value)
203 : pci_read_config_dword(root, 0x64, value));
204 if (err)
205 pr_warn("Error %s SMN address 0x%x.\n",
206 (write ? "writing to" : "reading from"), address);
207
208out_unlock:
209 mutex_unlock(&smn_mutex);
210
211out:
212 return err;
213}
214
215int amd_smn_read(u16 node, u32 address, u32 *value)
216{
217 return __amd_smn_rw(node, address, value, false);
218}
219EXPORT_SYMBOL_GPL(amd_smn_read);
220
221int amd_smn_write(u16 node, u32 address, u32 value)
222{
223 return __amd_smn_rw(node, address, &value, true);
224}
225EXPORT_SYMBOL_GPL(amd_smn_write);
226
227
228static int amd_cache_northbridges(void)
229{
230 const struct pci_device_id *misc_ids = amd_nb_misc_ids;
231 const struct pci_device_id *link_ids = amd_nb_link_ids;
232 const struct pci_device_id *root_ids = amd_root_ids;
233 struct pci_dev *root, *misc, *link;
234 struct amd_northbridge *nb;
235 u16 roots_per_misc = 0;
236 u16 misc_count = 0;
237 u16 root_count = 0;
238 u16 i, j;
239
240 if (amd_northbridges.num)
241 return 0;
242
243 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
244 root_ids = hygon_root_ids;
245 misc_ids = hygon_nb_misc_ids;
246 link_ids = hygon_nb_link_ids;
247 }
248
249 misc = NULL;
250 while ((misc = next_northbridge(misc, misc_ids)))
251 misc_count++;
252
253 if (!misc_count)
254 return -ENODEV;
255
256 root = NULL;
257 while ((root = next_northbridge(root, root_ids)))
258 root_count++;
259
260 if (root_count) {
261 roots_per_misc = root_count / misc_count;
262
263 /*
264 * There should be _exactly_ N roots for each DF/SMN
265 * interface.
266 */
267 if (!roots_per_misc || (root_count % roots_per_misc)) {
268 pr_info("Unsupported AMD DF/PCI configuration found\n");
269 return -ENODEV;
270 }
271 }
272
273 nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
274 if (!nb)
275 return -ENOMEM;
276
277 amd_northbridges.nb = nb;
278 amd_northbridges.num = misc_count;
279
280 link = misc = root = NULL;
281 for (i = 0; i < amd_northbridges.num; i++) {
282 node_to_amd_nb(i)->root = root =
283 next_northbridge(root, root_ids);
284 node_to_amd_nb(i)->misc = misc =
285 next_northbridge(misc, misc_ids);
286 node_to_amd_nb(i)->link = link =
287 next_northbridge(link, link_ids);
288
289 /*
290 * If there are more PCI root devices than data fabric/
291 * system management network interfaces, then the (N)
292 * PCI roots per DF/SMN interface are functionally the
293 * same (for DF/SMN access) and N-1 are redundant. N-1
294 * PCI roots should be skipped per DF/SMN interface so
295 * the following DF/SMN interfaces get mapped to
296 * correct PCI roots.
297 */
298 for (j = 1; j < roots_per_misc; j++)
299 root = next_northbridge(root, root_ids);
300 }
301
302 if (amd_gart_present())
303 amd_northbridges.flags |= AMD_NB_GART;
304
305 /*
306 * Check for L3 cache presence.
307 */
308 if (!cpuid_edx(0x80000006))
309 return 0;
310
311 /*
312 * Some CPU families support L3 Cache Index Disable. There are some
313 * limitations because of E382 and E388 on family 0x10.
314 */
315 if (boot_cpu_data.x86 == 0x10 &&
316 boot_cpu_data.x86_model >= 0x8 &&
317 (boot_cpu_data.x86_model > 0x9 ||
318 boot_cpu_data.x86_stepping >= 0x1))
319 amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
320
321 if (boot_cpu_data.x86 == 0x15)
322 amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
323
324 /* L3 cache partitioning is supported on family 0x15 */
325 if (boot_cpu_data.x86 == 0x15)
326 amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
327
328 return 0;
329}
330
331/*
332 * Ignores subdevice/subvendor but as far as I can figure out
333 * they're useless anyways
334 */
335bool __init early_is_amd_nb(u32 device)
336{
337 const struct pci_device_id *misc_ids = amd_nb_misc_ids;
338 const struct pci_device_id *id;
339 u32 vendor = device & 0xffff;
340
341 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
342 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
343 return false;
344
345 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
346 misc_ids = hygon_nb_misc_ids;
347
348 device >>= 16;
349 for (id = misc_ids; id->vendor; id++)
350 if (vendor == id->vendor && device == id->device)
351 return true;
352 return false;
353}
354
355struct resource *amd_get_mmconfig_range(struct resource *res)
356{
357 u32 address;
358 u64 base, msr;
359 unsigned int segn_busn_bits;
360
361 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
362 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
363 return NULL;
364
365 /* assume all cpus from fam10h have mmconfig */
366 if (boot_cpu_data.x86 < 0x10)
367 return NULL;
368
369 address = MSR_FAM10H_MMIO_CONF_BASE;
370 rdmsrl(address, msr);
371
372 /* mmconfig is not enabled */
373 if (!(msr & FAM10H_MMIO_CONF_ENABLE))
374 return NULL;
375
376 base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
377
378 segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
379 FAM10H_MMIO_CONF_BUSRANGE_MASK;
380
381 res->flags = IORESOURCE_MEM;
382 res->start = base;
383 res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
384 return res;
385}
386
387int amd_get_subcaches(int cpu)
388{
389 struct pci_dev *link = node_to_amd_nb(topology_die_id(cpu))->link;
390 unsigned int mask;
391
392 if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
393 return 0;
394
395 pci_read_config_dword(link, 0x1d4, &mask);
396
397 return (mask >> (4 * cpu_data(cpu).topo.core_id)) & 0xf;
398}
399
400int amd_set_subcaches(int cpu, unsigned long mask)
401{
402 static unsigned int reset, ban;
403 struct amd_northbridge *nb = node_to_amd_nb(topology_die_id(cpu));
404 unsigned int reg;
405 int cuid;
406
407 if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
408 return -EINVAL;
409
410 /* if necessary, collect reset state of L3 partitioning and BAN mode */
411 if (reset == 0) {
412 pci_read_config_dword(nb->link, 0x1d4, &reset);
413 pci_read_config_dword(nb->misc, 0x1b8, &ban);
414 ban &= 0x180000;
415 }
416
417 /* deactivate BAN mode if any subcaches are to be disabled */
418 if (mask != 0xf) {
419 pci_read_config_dword(nb->misc, 0x1b8, ®);
420 pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
421 }
422
423 cuid = cpu_data(cpu).topo.core_id;
424 mask <<= 4 * cuid;
425 mask |= (0xf ^ (1 << cuid)) << 26;
426
427 pci_write_config_dword(nb->link, 0x1d4, mask);
428
429 /* reset BAN mode if L3 partitioning returned to reset state */
430 pci_read_config_dword(nb->link, 0x1d4, ®);
431 if (reg == reset) {
432 pci_read_config_dword(nb->misc, 0x1b8, ®);
433 reg &= ~0x180000;
434 pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
435 }
436
437 return 0;
438}
439
440static void amd_cache_gart(void)
441{
442 u16 i;
443
444 if (!amd_nb_has_feature(AMD_NB_GART))
445 return;
446
447 flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
448 if (!flush_words) {
449 amd_northbridges.flags &= ~AMD_NB_GART;
450 pr_notice("Cannot initialize GART flush words, GART support disabled\n");
451 return;
452 }
453
454 for (i = 0; i != amd_northbridges.num; i++)
455 pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
456}
457
458void amd_flush_garts(void)
459{
460 int flushed, i;
461 unsigned long flags;
462 static DEFINE_SPINLOCK(gart_lock);
463
464 if (!amd_nb_has_feature(AMD_NB_GART))
465 return;
466
467 /*
468 * Avoid races between AGP and IOMMU. In theory it's not needed
469 * but I'm not sure if the hardware won't lose flush requests
470 * when another is pending. This whole thing is so expensive anyways
471 * that it doesn't matter to serialize more. -AK
472 */
473 spin_lock_irqsave(&gart_lock, flags);
474 flushed = 0;
475 for (i = 0; i < amd_northbridges.num; i++) {
476 pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
477 flush_words[i] | 1);
478 flushed++;
479 }
480 for (i = 0; i < amd_northbridges.num; i++) {
481 u32 w;
482 /* Make sure the hardware actually executed the flush*/
483 for (;;) {
484 pci_read_config_dword(node_to_amd_nb(i)->misc,
485 0x9c, &w);
486 if (!(w & 1))
487 break;
488 cpu_relax();
489 }
490 }
491 spin_unlock_irqrestore(&gart_lock, flags);
492 if (!flushed)
493 pr_notice("nothing to flush?\n");
494}
495EXPORT_SYMBOL_GPL(amd_flush_garts);
496
497static void __fix_erratum_688(void *info)
498{
499#define MSR_AMD64_IC_CFG 0xC0011021
500
501 msr_set_bit(MSR_AMD64_IC_CFG, 3);
502 msr_set_bit(MSR_AMD64_IC_CFG, 14);
503}
504
505/* Apply erratum 688 fix so machines without a BIOS fix work. */
506static __init void fix_erratum_688(void)
507{
508 struct pci_dev *F4;
509 u32 val;
510
511 if (boot_cpu_data.x86 != 0x14)
512 return;
513
514 if (!amd_northbridges.num)
515 return;
516
517 F4 = node_to_amd_nb(0)->link;
518 if (!F4)
519 return;
520
521 if (pci_read_config_dword(F4, 0x164, &val))
522 return;
523
524 if (val & BIT(2))
525 return;
526
527 on_each_cpu(__fix_erratum_688, NULL, 0);
528
529 pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
530}
531
532static __init int init_amd_nbs(void)
533{
534 amd_cache_northbridges();
535 amd_cache_gart();
536
537 fix_erratum_688();
538
539 return 0;
540}
541
542/* This has to go after the PCI subsystem */
543fs_initcall(init_amd_nbs);
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_17H_DF_F4 0x1464
23#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
24#define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4 0x1494
25#define PCI_DEVICE_ID_AMD_17H_M60H_DF_F4 0x144c
26#define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4 0x1444
27#define PCI_DEVICE_ID_AMD_19H_DF_F4 0x1654
28#define PCI_DEVICE_ID_AMD_19H_M50H_DF_F4 0x166e
29
30/* Protect the PCI config register pairs used for SMN and DF indirect access. */
31static DEFINE_MUTEX(smn_mutex);
32
33static u32 *flush_words;
34
35static const struct pci_device_id amd_root_ids[] = {
36 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
37 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
38 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
39 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_ROOT) },
40 {}
41};
42
43#define PCI_DEVICE_ID_AMD_CNB17H_F4 0x1704
44
45static const struct pci_device_id amd_nb_misc_ids[] = {
46 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
47 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
48 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
49 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
50 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
51 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
52 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
53 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
54 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
55 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
56 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
57 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F3) },
58 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
59 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
60 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
61 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F3) },
62 {}
63};
64
65static const struct pci_device_id amd_nb_link_ids[] = {
66 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
67 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
68 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
69 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
70 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
71 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
72 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
73 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
74 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
75 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
76 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
77 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
78 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
79 {}
80};
81
82static const struct pci_device_id hygon_root_ids[] = {
83 { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
84 {}
85};
86
87static const struct pci_device_id hygon_nb_misc_ids[] = {
88 { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
89 {}
90};
91
92static const struct pci_device_id hygon_nb_link_ids[] = {
93 { PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
94 {}
95};
96
97const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
98 { 0x00, 0x18, 0x20 },
99 { 0xff, 0x00, 0x20 },
100 { 0xfe, 0x00, 0x20 },
101 { }
102};
103
104static struct amd_northbridge_info amd_northbridges;
105
106u16 amd_nb_num(void)
107{
108 return amd_northbridges.num;
109}
110EXPORT_SYMBOL_GPL(amd_nb_num);
111
112bool amd_nb_has_feature(unsigned int feature)
113{
114 return ((amd_northbridges.flags & feature) == feature);
115}
116EXPORT_SYMBOL_GPL(amd_nb_has_feature);
117
118struct amd_northbridge *node_to_amd_nb(int node)
119{
120 return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
121}
122EXPORT_SYMBOL_GPL(node_to_amd_nb);
123
124static struct pci_dev *next_northbridge(struct pci_dev *dev,
125 const struct pci_device_id *ids)
126{
127 do {
128 dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
129 if (!dev)
130 break;
131 } while (!pci_match_id(ids, dev));
132 return dev;
133}
134
135static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
136{
137 struct pci_dev *root;
138 int err = -ENODEV;
139
140 if (node >= amd_northbridges.num)
141 goto out;
142
143 root = node_to_amd_nb(node)->root;
144 if (!root)
145 goto out;
146
147 mutex_lock(&smn_mutex);
148
149 err = pci_write_config_dword(root, 0x60, address);
150 if (err) {
151 pr_warn("Error programming SMN address 0x%x.\n", address);
152 goto out_unlock;
153 }
154
155 err = (write ? pci_write_config_dword(root, 0x64, *value)
156 : pci_read_config_dword(root, 0x64, value));
157 if (err)
158 pr_warn("Error %s SMN address 0x%x.\n",
159 (write ? "writing to" : "reading from"), address);
160
161out_unlock:
162 mutex_unlock(&smn_mutex);
163
164out:
165 return err;
166}
167
168int amd_smn_read(u16 node, u32 address, u32 *value)
169{
170 return __amd_smn_rw(node, address, value, false);
171}
172EXPORT_SYMBOL_GPL(amd_smn_read);
173
174int amd_smn_write(u16 node, u32 address, u32 value)
175{
176 return __amd_smn_rw(node, address, &value, true);
177}
178EXPORT_SYMBOL_GPL(amd_smn_write);
179
180/*
181 * Data Fabric Indirect Access uses FICAA/FICAD.
182 *
183 * Fabric Indirect Configuration Access Address (FICAA): Constructed based
184 * on the device's Instance Id and the PCI function and register offset of
185 * the desired register.
186 *
187 * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
188 * and FICAD HI registers but so far we only need the LO register.
189 */
190int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
191{
192 struct pci_dev *F4;
193 u32 ficaa;
194 int err = -ENODEV;
195
196 if (node >= amd_northbridges.num)
197 goto out;
198
199 F4 = node_to_amd_nb(node)->link;
200 if (!F4)
201 goto out;
202
203 ficaa = 1;
204 ficaa |= reg & 0x3FC;
205 ficaa |= (func & 0x7) << 11;
206 ficaa |= instance_id << 16;
207
208 mutex_lock(&smn_mutex);
209
210 err = pci_write_config_dword(F4, 0x5C, ficaa);
211 if (err) {
212 pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
213 goto out_unlock;
214 }
215
216 err = pci_read_config_dword(F4, 0x98, lo);
217 if (err)
218 pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
219
220out_unlock:
221 mutex_unlock(&smn_mutex);
222
223out:
224 return err;
225}
226EXPORT_SYMBOL_GPL(amd_df_indirect_read);
227
228int amd_cache_northbridges(void)
229{
230 const struct pci_device_id *misc_ids = amd_nb_misc_ids;
231 const struct pci_device_id *link_ids = amd_nb_link_ids;
232 const struct pci_device_id *root_ids = amd_root_ids;
233 struct pci_dev *root, *misc, *link;
234 struct amd_northbridge *nb;
235 u16 roots_per_misc = 0;
236 u16 misc_count = 0;
237 u16 root_count = 0;
238 u16 i, j;
239
240 if (amd_northbridges.num)
241 return 0;
242
243 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
244 root_ids = hygon_root_ids;
245 misc_ids = hygon_nb_misc_ids;
246 link_ids = hygon_nb_link_ids;
247 }
248
249 misc = NULL;
250 while ((misc = next_northbridge(misc, misc_ids)) != NULL)
251 misc_count++;
252
253 if (!misc_count)
254 return -ENODEV;
255
256 root = NULL;
257 while ((root = next_northbridge(root, root_ids)) != NULL)
258 root_count++;
259
260 if (root_count) {
261 roots_per_misc = root_count / misc_count;
262
263 /*
264 * There should be _exactly_ N roots for each DF/SMN
265 * interface.
266 */
267 if (!roots_per_misc || (root_count % roots_per_misc)) {
268 pr_info("Unsupported AMD DF/PCI configuration found\n");
269 return -ENODEV;
270 }
271 }
272
273 nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
274 if (!nb)
275 return -ENOMEM;
276
277 amd_northbridges.nb = nb;
278 amd_northbridges.num = misc_count;
279
280 link = misc = root = NULL;
281 for (i = 0; i < amd_northbridges.num; i++) {
282 node_to_amd_nb(i)->root = root =
283 next_northbridge(root, root_ids);
284 node_to_amd_nb(i)->misc = misc =
285 next_northbridge(misc, misc_ids);
286 node_to_amd_nb(i)->link = link =
287 next_northbridge(link, link_ids);
288
289 /*
290 * If there are more PCI root devices than data fabric/
291 * system management network interfaces, then the (N)
292 * PCI roots per DF/SMN interface are functionally the
293 * same (for DF/SMN access) and N-1 are redundant. N-1
294 * PCI roots should be skipped per DF/SMN interface so
295 * the following DF/SMN interfaces get mapped to
296 * correct PCI roots.
297 */
298 for (j = 1; j < roots_per_misc; j++)
299 root = next_northbridge(root, root_ids);
300 }
301
302 if (amd_gart_present())
303 amd_northbridges.flags |= AMD_NB_GART;
304
305 /*
306 * Check for L3 cache presence.
307 */
308 if (!cpuid_edx(0x80000006))
309 return 0;
310
311 /*
312 * Some CPU families support L3 Cache Index Disable. There are some
313 * limitations because of E382 and E388 on family 0x10.
314 */
315 if (boot_cpu_data.x86 == 0x10 &&
316 boot_cpu_data.x86_model >= 0x8 &&
317 (boot_cpu_data.x86_model > 0x9 ||
318 boot_cpu_data.x86_stepping >= 0x1))
319 amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
320
321 if (boot_cpu_data.x86 == 0x15)
322 amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
323
324 /* L3 cache partitioning is supported on family 0x15 */
325 if (boot_cpu_data.x86 == 0x15)
326 amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
327
328 return 0;
329}
330EXPORT_SYMBOL_GPL(amd_cache_northbridges);
331
332/*
333 * Ignores subdevice/subvendor but as far as I can figure out
334 * they're useless anyways
335 */
336bool __init early_is_amd_nb(u32 device)
337{
338 const struct pci_device_id *misc_ids = amd_nb_misc_ids;
339 const struct pci_device_id *id;
340 u32 vendor = device & 0xffff;
341
342 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
343 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
344 return false;
345
346 if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
347 misc_ids = hygon_nb_misc_ids;
348
349 device >>= 16;
350 for (id = misc_ids; id->vendor; id++)
351 if (vendor == id->vendor && device == id->device)
352 return true;
353 return false;
354}
355
356struct resource *amd_get_mmconfig_range(struct resource *res)
357{
358 u32 address;
359 u64 base, msr;
360 unsigned int segn_busn_bits;
361
362 if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
363 boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
364 return NULL;
365
366 /* assume all cpus from fam10h have mmconfig */
367 if (boot_cpu_data.x86 < 0x10)
368 return NULL;
369
370 address = MSR_FAM10H_MMIO_CONF_BASE;
371 rdmsrl(address, msr);
372
373 /* mmconfig is not enabled */
374 if (!(msr & FAM10H_MMIO_CONF_ENABLE))
375 return NULL;
376
377 base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
378
379 segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
380 FAM10H_MMIO_CONF_BUSRANGE_MASK;
381
382 res->flags = IORESOURCE_MEM;
383 res->start = base;
384 res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
385 return res;
386}
387
388int amd_get_subcaches(int cpu)
389{
390 struct pci_dev *link = node_to_amd_nb(topology_die_id(cpu))->link;
391 unsigned int mask;
392
393 if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
394 return 0;
395
396 pci_read_config_dword(link, 0x1d4, &mask);
397
398 return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
399}
400
401int amd_set_subcaches(int cpu, unsigned long mask)
402{
403 static unsigned int reset, ban;
404 struct amd_northbridge *nb = node_to_amd_nb(topology_die_id(cpu));
405 unsigned int reg;
406 int cuid;
407
408 if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
409 return -EINVAL;
410
411 /* if necessary, collect reset state of L3 partitioning and BAN mode */
412 if (reset == 0) {
413 pci_read_config_dword(nb->link, 0x1d4, &reset);
414 pci_read_config_dword(nb->misc, 0x1b8, &ban);
415 ban &= 0x180000;
416 }
417
418 /* deactivate BAN mode if any subcaches are to be disabled */
419 if (mask != 0xf) {
420 pci_read_config_dword(nb->misc, 0x1b8, ®);
421 pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
422 }
423
424 cuid = cpu_data(cpu).cpu_core_id;
425 mask <<= 4 * cuid;
426 mask |= (0xf ^ (1 << cuid)) << 26;
427
428 pci_write_config_dword(nb->link, 0x1d4, mask);
429
430 /* reset BAN mode if L3 partitioning returned to reset state */
431 pci_read_config_dword(nb->link, 0x1d4, ®);
432 if (reg == reset) {
433 pci_read_config_dword(nb->misc, 0x1b8, ®);
434 reg &= ~0x180000;
435 pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
436 }
437
438 return 0;
439}
440
441static void amd_cache_gart(void)
442{
443 u16 i;
444
445 if (!amd_nb_has_feature(AMD_NB_GART))
446 return;
447
448 flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
449 if (!flush_words) {
450 amd_northbridges.flags &= ~AMD_NB_GART;
451 pr_notice("Cannot initialize GART flush words, GART support disabled\n");
452 return;
453 }
454
455 for (i = 0; i != amd_northbridges.num; i++)
456 pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
457}
458
459void amd_flush_garts(void)
460{
461 int flushed, i;
462 unsigned long flags;
463 static DEFINE_SPINLOCK(gart_lock);
464
465 if (!amd_nb_has_feature(AMD_NB_GART))
466 return;
467
468 /*
469 * Avoid races between AGP and IOMMU. In theory it's not needed
470 * but I'm not sure if the hardware won't lose flush requests
471 * when another is pending. This whole thing is so expensive anyways
472 * that it doesn't matter to serialize more. -AK
473 */
474 spin_lock_irqsave(&gart_lock, flags);
475 flushed = 0;
476 for (i = 0; i < amd_northbridges.num; i++) {
477 pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
478 flush_words[i] | 1);
479 flushed++;
480 }
481 for (i = 0; i < amd_northbridges.num; i++) {
482 u32 w;
483 /* Make sure the hardware actually executed the flush*/
484 for (;;) {
485 pci_read_config_dword(node_to_amd_nb(i)->misc,
486 0x9c, &w);
487 if (!(w & 1))
488 break;
489 cpu_relax();
490 }
491 }
492 spin_unlock_irqrestore(&gart_lock, flags);
493 if (!flushed)
494 pr_notice("nothing to flush?\n");
495}
496EXPORT_SYMBOL_GPL(amd_flush_garts);
497
498static void __fix_erratum_688(void *info)
499{
500#define MSR_AMD64_IC_CFG 0xC0011021
501
502 msr_set_bit(MSR_AMD64_IC_CFG, 3);
503 msr_set_bit(MSR_AMD64_IC_CFG, 14);
504}
505
506/* Apply erratum 688 fix so machines without a BIOS fix work. */
507static __init void fix_erratum_688(void)
508{
509 struct pci_dev *F4;
510 u32 val;
511
512 if (boot_cpu_data.x86 != 0x14)
513 return;
514
515 if (!amd_northbridges.num)
516 return;
517
518 F4 = node_to_amd_nb(0)->link;
519 if (!F4)
520 return;
521
522 if (pci_read_config_dword(F4, 0x164, &val))
523 return;
524
525 if (val & BIT(2))
526 return;
527
528 on_each_cpu(__fix_erratum_688, NULL, 0);
529
530 pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
531}
532
533static __init int init_amd_nbs(void)
534{
535 amd_cache_northbridges();
536 amd_cache_gart();
537
538 fix_erratum_688();
539
540 return 0;
541}
542
543/* This has to go after the PCI subsystem */
544fs_initcall(init_amd_nbs);