xref: /linux/arch/x86/kernel/amd_nb.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
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. */
50 static DEFINE_MUTEX(smn_mutex);
51 
52 static u32 *flush_words;
53 
54 static 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 
73 static 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_1AH_M70H_DF_F3) },
99 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F3) },
100 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_DF_F3) },
101 	{}
102 };
103 
104 static const struct pci_device_id amd_nb_link_ids[] = {
105 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
106 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
107 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
108 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
109 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
110 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
111 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
112 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
113 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
114 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
115 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_DF_F4) },
116 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
117 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F4) },
118 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F4) },
119 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
120 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_DF_F4) },
121 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_DF_F4) },
122 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M78H_DF_F4) },
123 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
124 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4) },
125 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F4) },
126 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_DF_F4) },
127 	{}
128 };
129 
130 static const struct pci_device_id hygon_root_ids[] = {
131 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
132 	{}
133 };
134 
135 static const struct pci_device_id hygon_nb_misc_ids[] = {
136 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
137 	{}
138 };
139 
140 static const struct pci_device_id hygon_nb_link_ids[] = {
141 	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
142 	{}
143 };
144 
145 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
146 	{ 0x00, 0x18, 0x20 },
147 	{ 0xff, 0x00, 0x20 },
148 	{ 0xfe, 0x00, 0x20 },
149 	{ }
150 };
151 
152 static struct amd_northbridge_info amd_northbridges;
153 
154 u16 amd_nb_num(void)
155 {
156 	return amd_northbridges.num;
157 }
158 EXPORT_SYMBOL_GPL(amd_nb_num);
159 
160 bool amd_nb_has_feature(unsigned int feature)
161 {
162 	return ((amd_northbridges.flags & feature) == feature);
163 }
164 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
165 
166 struct amd_northbridge *node_to_amd_nb(int node)
167 {
168 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
169 }
170 EXPORT_SYMBOL_GPL(node_to_amd_nb);
171 
172 static struct pci_dev *next_northbridge(struct pci_dev *dev,
173 					const struct pci_device_id *ids)
174 {
175 	do {
176 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
177 		if (!dev)
178 			break;
179 	} while (!pci_match_id(ids, dev));
180 	return dev;
181 }
182 
183 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
184 {
185 	struct pci_dev *root;
186 	int err = -ENODEV;
187 
188 	if (node >= amd_northbridges.num)
189 		goto out;
190 
191 	root = node_to_amd_nb(node)->root;
192 	if (!root)
193 		goto out;
194 
195 	mutex_lock(&smn_mutex);
196 
197 	err = pci_write_config_dword(root, 0x60, address);
198 	if (err) {
199 		pr_warn("Error programming SMN address 0x%x.\n", address);
200 		goto out_unlock;
201 	}
202 
203 	err = (write ? pci_write_config_dword(root, 0x64, *value)
204 		     : pci_read_config_dword(root, 0x64, value));
205 	if (err)
206 		pr_warn("Error %s SMN address 0x%x.\n",
207 			(write ? "writing to" : "reading from"), address);
208 
209 out_unlock:
210 	mutex_unlock(&smn_mutex);
211 
212 out:
213 	return err;
214 }
215 
216 int amd_smn_read(u16 node, u32 address, u32 *value)
217 {
218 	int err = __amd_smn_rw(node, address, value, false);
219 
220 	if (PCI_POSSIBLE_ERROR(*value)) {
221 		err = -ENODEV;
222 		*value = 0;
223 	}
224 
225 	return err;
226 }
227 EXPORT_SYMBOL_GPL(amd_smn_read);
228 
229 int amd_smn_write(u16 node, u32 address, u32 value)
230 {
231 	return __amd_smn_rw(node, address, &value, true);
232 }
233 EXPORT_SYMBOL_GPL(amd_smn_write);
234 
235 
236 static int amd_cache_northbridges(void)
237 {
238 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
239 	const struct pci_device_id *link_ids = amd_nb_link_ids;
240 	const struct pci_device_id *root_ids = amd_root_ids;
241 	struct pci_dev *root, *misc, *link;
242 	struct amd_northbridge *nb;
243 	u16 roots_per_misc = 0;
244 	u16 misc_count = 0;
245 	u16 root_count = 0;
246 	u16 i, j;
247 
248 	if (amd_northbridges.num)
249 		return 0;
250 
251 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
252 		root_ids = hygon_root_ids;
253 		misc_ids = hygon_nb_misc_ids;
254 		link_ids = hygon_nb_link_ids;
255 	}
256 
257 	misc = NULL;
258 	while ((misc = next_northbridge(misc, misc_ids)))
259 		misc_count++;
260 
261 	if (!misc_count)
262 		return -ENODEV;
263 
264 	root = NULL;
265 	while ((root = next_northbridge(root, root_ids)))
266 		root_count++;
267 
268 	if (root_count) {
269 		roots_per_misc = root_count / misc_count;
270 
271 		/*
272 		 * There should be _exactly_ N roots for each DF/SMN
273 		 * interface.
274 		 */
275 		if (!roots_per_misc || (root_count % roots_per_misc)) {
276 			pr_info("Unsupported AMD DF/PCI configuration found\n");
277 			return -ENODEV;
278 		}
279 	}
280 
281 	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
282 	if (!nb)
283 		return -ENOMEM;
284 
285 	amd_northbridges.nb = nb;
286 	amd_northbridges.num = misc_count;
287 
288 	link = misc = root = NULL;
289 	for (i = 0; i < amd_northbridges.num; i++) {
290 		node_to_amd_nb(i)->root = root =
291 			next_northbridge(root, root_ids);
292 		node_to_amd_nb(i)->misc = misc =
293 			next_northbridge(misc, misc_ids);
294 		node_to_amd_nb(i)->link = link =
295 			next_northbridge(link, link_ids);
296 
297 		/*
298 		 * If there are more PCI root devices than data fabric/
299 		 * system management network interfaces, then the (N)
300 		 * PCI roots per DF/SMN interface are functionally the
301 		 * same (for DF/SMN access) and N-1 are redundant.  N-1
302 		 * PCI roots should be skipped per DF/SMN interface so
303 		 * the following DF/SMN interfaces get mapped to
304 		 * correct PCI roots.
305 		 */
306 		for (j = 1; j < roots_per_misc; j++)
307 			root = next_northbridge(root, root_ids);
308 	}
309 
310 	if (amd_gart_present())
311 		amd_northbridges.flags |= AMD_NB_GART;
312 
313 	/*
314 	 * Check for L3 cache presence.
315 	 */
316 	if (!cpuid_edx(0x80000006))
317 		return 0;
318 
319 	/*
320 	 * Some CPU families support L3 Cache Index Disable. There are some
321 	 * limitations because of E382 and E388 on family 0x10.
322 	 */
323 	if (boot_cpu_data.x86 == 0x10 &&
324 	    boot_cpu_data.x86_model >= 0x8 &&
325 	    (boot_cpu_data.x86_model > 0x9 ||
326 	     boot_cpu_data.x86_stepping >= 0x1))
327 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
328 
329 	if (boot_cpu_data.x86 == 0x15)
330 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
331 
332 	/* L3 cache partitioning is supported on family 0x15 */
333 	if (boot_cpu_data.x86 == 0x15)
334 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
335 
336 	return 0;
337 }
338 
339 /*
340  * Ignores subdevice/subvendor but as far as I can figure out
341  * they're useless anyways
342  */
343 bool __init early_is_amd_nb(u32 device)
344 {
345 	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
346 	const struct pci_device_id *id;
347 	u32 vendor = device & 0xffff;
348 
349 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
350 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
351 		return false;
352 
353 	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
354 		misc_ids = hygon_nb_misc_ids;
355 
356 	device >>= 16;
357 	for (id = misc_ids; id->vendor; id++)
358 		if (vendor == id->vendor && device == id->device)
359 			return true;
360 	return false;
361 }
362 
363 struct resource *amd_get_mmconfig_range(struct resource *res)
364 {
365 	u32 address;
366 	u64 base, msr;
367 	unsigned int segn_busn_bits;
368 
369 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
370 	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
371 		return NULL;
372 
373 	/* assume all cpus from fam10h have mmconfig */
374 	if (boot_cpu_data.x86 < 0x10)
375 		return NULL;
376 
377 	address = MSR_FAM10H_MMIO_CONF_BASE;
378 	rdmsrl(address, msr);
379 
380 	/* mmconfig is not enabled */
381 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
382 		return NULL;
383 
384 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
385 
386 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
387 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
388 
389 	res->flags = IORESOURCE_MEM;
390 	res->start = base;
391 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
392 	return res;
393 }
394 
395 int amd_get_subcaches(int cpu)
396 {
397 	struct pci_dev *link = node_to_amd_nb(topology_amd_node_id(cpu))->link;
398 	unsigned int mask;
399 
400 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
401 		return 0;
402 
403 	pci_read_config_dword(link, 0x1d4, &mask);
404 
405 	return (mask >> (4 * cpu_data(cpu).topo.core_id)) & 0xf;
406 }
407 
408 int amd_set_subcaches(int cpu, unsigned long mask)
409 {
410 	static unsigned int reset, ban;
411 	struct amd_northbridge *nb = node_to_amd_nb(topology_amd_node_id(cpu));
412 	unsigned int reg;
413 	int cuid;
414 
415 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
416 		return -EINVAL;
417 
418 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
419 	if (reset == 0) {
420 		pci_read_config_dword(nb->link, 0x1d4, &reset);
421 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
422 		ban &= 0x180000;
423 	}
424 
425 	/* deactivate BAN mode if any subcaches are to be disabled */
426 	if (mask != 0xf) {
427 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
428 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
429 	}
430 
431 	cuid = cpu_data(cpu).topo.core_id;
432 	mask <<= 4 * cuid;
433 	mask |= (0xf ^ (1 << cuid)) << 26;
434 
435 	pci_write_config_dword(nb->link, 0x1d4, mask);
436 
437 	/* reset BAN mode if L3 partitioning returned to reset state */
438 	pci_read_config_dword(nb->link, 0x1d4, &reg);
439 	if (reg == reset) {
440 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
441 		reg &= ~0x180000;
442 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
443 	}
444 
445 	return 0;
446 }
447 
448 static void amd_cache_gart(void)
449 {
450 	u16 i;
451 
452 	if (!amd_nb_has_feature(AMD_NB_GART))
453 		return;
454 
455 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
456 	if (!flush_words) {
457 		amd_northbridges.flags &= ~AMD_NB_GART;
458 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
459 		return;
460 	}
461 
462 	for (i = 0; i != amd_northbridges.num; i++)
463 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
464 }
465 
466 void amd_flush_garts(void)
467 {
468 	int flushed, i;
469 	unsigned long flags;
470 	static DEFINE_SPINLOCK(gart_lock);
471 
472 	if (!amd_nb_has_feature(AMD_NB_GART))
473 		return;
474 
475 	/*
476 	 * Avoid races between AGP and IOMMU. In theory it's not needed
477 	 * but I'm not sure if the hardware won't lose flush requests
478 	 * when another is pending. This whole thing is so expensive anyways
479 	 * that it doesn't matter to serialize more. -AK
480 	 */
481 	spin_lock_irqsave(&gart_lock, flags);
482 	flushed = 0;
483 	for (i = 0; i < amd_northbridges.num; i++) {
484 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
485 				       flush_words[i] | 1);
486 		flushed++;
487 	}
488 	for (i = 0; i < amd_northbridges.num; i++) {
489 		u32 w;
490 		/* Make sure the hardware actually executed the flush*/
491 		for (;;) {
492 			pci_read_config_dword(node_to_amd_nb(i)->misc,
493 					      0x9c, &w);
494 			if (!(w & 1))
495 				break;
496 			cpu_relax();
497 		}
498 	}
499 	spin_unlock_irqrestore(&gart_lock, flags);
500 	if (!flushed)
501 		pr_notice("nothing to flush?\n");
502 }
503 EXPORT_SYMBOL_GPL(amd_flush_garts);
504 
505 static void __fix_erratum_688(void *info)
506 {
507 #define MSR_AMD64_IC_CFG 0xC0011021
508 
509 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
510 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
511 }
512 
513 /* Apply erratum 688 fix so machines without a BIOS fix work. */
514 static __init void fix_erratum_688(void)
515 {
516 	struct pci_dev *F4;
517 	u32 val;
518 
519 	if (boot_cpu_data.x86 != 0x14)
520 		return;
521 
522 	if (!amd_northbridges.num)
523 		return;
524 
525 	F4 = node_to_amd_nb(0)->link;
526 	if (!F4)
527 		return;
528 
529 	if (pci_read_config_dword(F4, 0x164, &val))
530 		return;
531 
532 	if (val & BIT(2))
533 		return;
534 
535 	on_each_cpu(__fix_erratum_688, NULL, 0);
536 
537 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
538 }
539 
540 static __init int init_amd_nbs(void)
541 {
542 	amd_cache_northbridges();
543 	amd_cache_gart();
544 
545 	fix_erratum_688();
546 
547 	return 0;
548 }
549 
550 /* This has to go after the PCI subsystem */
551 fs_initcall(init_amd_nbs);
552