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v6.13.7
  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_1AH_M60H_ROOT		0x1122
 30#define PCI_DEVICE_ID_AMD_MI200_ROOT		0x14bb
 31#define PCI_DEVICE_ID_AMD_MI300_ROOT		0x14f8
 32
 33#define PCI_DEVICE_ID_AMD_17H_DF_F4		0x1464
 34#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4	0x15ec
 35#define PCI_DEVICE_ID_AMD_17H_M30H_DF_F4	0x1494
 36#define PCI_DEVICE_ID_AMD_17H_M60H_DF_F4	0x144c
 37#define PCI_DEVICE_ID_AMD_17H_M70H_DF_F4	0x1444
 38#define PCI_DEVICE_ID_AMD_17H_MA0H_DF_F4	0x1728
 39#define PCI_DEVICE_ID_AMD_19H_DF_F4		0x1654
 40#define PCI_DEVICE_ID_AMD_19H_M10H_DF_F4	0x14b1
 41#define PCI_DEVICE_ID_AMD_19H_M40H_DF_F4	0x167d
 42#define PCI_DEVICE_ID_AMD_19H_M50H_DF_F4	0x166e
 43#define PCI_DEVICE_ID_AMD_19H_M60H_DF_F4	0x14e4
 44#define PCI_DEVICE_ID_AMD_19H_M70H_DF_F4	0x14f4
 45#define PCI_DEVICE_ID_AMD_19H_M78H_DF_F4	0x12fc
 46#define PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4	0x12c4
 47#define PCI_DEVICE_ID_AMD_1AH_M20H_DF_F4	0x16fc
 48#define PCI_DEVICE_ID_AMD_1AH_M60H_DF_F4	0x124c
 49#define PCI_DEVICE_ID_AMD_1AH_M70H_DF_F4	0x12bc
 50#define PCI_DEVICE_ID_AMD_MI200_DF_F4		0x14d4
 51#define PCI_DEVICE_ID_AMD_MI300_DF_F4		0x152c
 52
 53/* Protect the PCI config register pairs used for SMN. */
 54static DEFINE_MUTEX(smn_mutex);
 55
 56static u32 *flush_words;
 57
 58static const struct pci_device_id amd_root_ids[] = {
 59	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
 60	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
 61	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_ROOT) },
 62	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_ROOT) },
 63	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_ROOT) },
 64	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_ROOT) },
 65	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_ROOT) },
 66	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_ROOT) },
 67	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_ROOT) },
 68	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_ROOT) },
 69	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_ROOT) },
 70	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M60H_ROOT) },
 71	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_ROOT) },
 72	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_ROOT) },
 73	{}
 74};
 75
 76#define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
 77
 78static const struct pci_device_id amd_nb_misc_ids[] = {
 79	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
 80	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
 81	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
 82	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
 83	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
 84	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
 85	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
 86	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
 87	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
 88	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
 89	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F3) },
 90	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F3) },
 91	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_DF_F3) },
 92	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
 93	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F3) },
 94	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F3) },
 95	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F3) },
 96	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F3) },
 97	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F3) },
 98	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_DF_F3) },
 99	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_DF_F3) },
100	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M78H_DF_F3) },
101	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F3) },
102	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_DF_F3) },
103	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M60H_DF_F3) },
104	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M70H_DF_F3) },
105	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F3) },
106	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_DF_F3) },
107	{}
108};
 
109
110static const struct pci_device_id amd_nb_link_ids[] = {
111	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
112	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
113	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
114	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
115	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
116	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
117	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
118	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M30H_DF_F4) },
119	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M60H_DF_F4) },
120	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M70H_DF_F4) },
121	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_MA0H_DF_F4) },
122	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_DF_F4) },
123	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M10H_DF_F4) },
124	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M40H_DF_F4) },
125	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M50H_DF_F4) },
126	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M60H_DF_F4) },
127	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M70H_DF_F4) },
128	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_19H_M78H_DF_F4) },
129	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
130	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M00H_DF_F4) },
131	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M20H_DF_F4) },
132	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M60H_DF_F4) },
133	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_1AH_M70H_DF_F4) },
134	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI200_DF_F4) },
135	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_MI300_DF_F4) },
136	{}
137};
138
139static const struct pci_device_id hygon_root_ids[] = {
140	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_ROOT) },
141	{}
142};
143
144static const struct pci_device_id hygon_nb_misc_ids[] = {
145	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F3) },
146	{}
147};
148
149static const struct pci_device_id hygon_nb_link_ids[] = {
150	{ PCI_DEVICE(PCI_VENDOR_ID_HYGON, PCI_DEVICE_ID_AMD_17H_DF_F4) },
151	{}
152};
153
154const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
155	{ 0x00, 0x18, 0x20 },
156	{ 0xff, 0x00, 0x20 },
157	{ 0xfe, 0x00, 0x20 },
158	{ }
159};
160
161static struct amd_northbridge_info amd_northbridges;
162
163u16 amd_nb_num(void)
164{
165	return amd_northbridges.num;
166}
167EXPORT_SYMBOL_GPL(amd_nb_num);
168
169bool amd_nb_has_feature(unsigned int feature)
170{
171	return ((amd_northbridges.flags & feature) == feature);
172}
173EXPORT_SYMBOL_GPL(amd_nb_has_feature);
174
175struct amd_northbridge *node_to_amd_nb(int node)
176{
177	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
178}
179EXPORT_SYMBOL_GPL(node_to_amd_nb);
180
181static struct pci_dev *next_northbridge(struct pci_dev *dev,
182					const struct pci_device_id *ids)
183{
184	do {
185		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
186		if (!dev)
187			break;
188	} while (!pci_match_id(ids, dev));
189	return dev;
190}
191
192/*
193 * SMN accesses may fail in ways that are difficult to detect here in the called
194 * functions amd_smn_read() and amd_smn_write(). Therefore, callers must do
195 * their own checking based on what behavior they expect.
196 *
197 * For SMN reads, the returned value may be zero if the register is Read-as-Zero.
198 * Or it may be a "PCI Error Response", e.g. all 0xFFs. The "PCI Error Response"
199 * can be checked here, and a proper error code can be returned.
200 *
201 * But the Read-as-Zero response cannot be verified here. A value of 0 may be
202 * correct in some cases, so callers must check that this correct is for the
203 * register/fields they need.
204 *
205 * For SMN writes, success can be determined through a "write and read back"
206 * However, this is not robust when done here.
207 *
208 * Possible issues:
209 *
210 * 1) Bits that are "Write-1-to-Clear". In this case, the read value should
211 *    *not* match the write value.
212 *
213 * 2) Bits that are "Read-as-Zero"/"Writes-Ignored". This information cannot be
214 *    known here.
215 *
216 * 3) Bits that are "Reserved / Set to 1". Ditto above.
217 *
218 * Callers of amd_smn_write() should do the "write and read back" check
219 * themselves, if needed.
220 *
221 * For #1, they can see if their target bits got cleared.
222 *
223 * For #2 and #3, they can check if their target bits got set as intended.
224 *
225 * This matches what is done for RDMSR/WRMSR. As long as there's no #GP, then
226 * the operation is considered a success, and the caller does their own
227 * checking.
228 */
229static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
230{
231	struct pci_dev *root;
232	int err = -ENODEV;
233
234	if (node >= amd_northbridges.num)
235		goto out;
236
237	root = node_to_amd_nb(node)->root;
238	if (!root)
239		goto out;
240
241	mutex_lock(&smn_mutex);
242
243	err = pci_write_config_dword(root, 0x60, address);
244	if (err) {
245		pr_warn("Error programming SMN address 0x%x.\n", address);
246		goto out_unlock;
247	}
248
249	err = (write ? pci_write_config_dword(root, 0x64, *value)
250		     : pci_read_config_dword(root, 0x64, value));
 
 
 
251
252out_unlock:
253	mutex_unlock(&smn_mutex);
254
255out:
256	return err;
257}
258
259int __must_check amd_smn_read(u16 node, u32 address, u32 *value)
260{
261	int err = __amd_smn_rw(node, address, value, false);
262
263	if (PCI_POSSIBLE_ERROR(*value)) {
264		err = -ENODEV;
265		*value = 0;
266	}
267
268	return err;
269}
270EXPORT_SYMBOL_GPL(amd_smn_read);
271
272int __must_check amd_smn_write(u16 node, u32 address, u32 value)
273{
274	return __amd_smn_rw(node, address, &value, true);
275}
276EXPORT_SYMBOL_GPL(amd_smn_write);
277
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
278
279static int amd_cache_northbridges(void)
280{
281	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
282	const struct pci_device_id *link_ids = amd_nb_link_ids;
283	const struct pci_device_id *root_ids = amd_root_ids;
284	struct pci_dev *root, *misc, *link;
285	struct amd_northbridge *nb;
286	u16 roots_per_misc = 0;
287	u16 misc_count = 0;
288	u16 root_count = 0;
289	u16 i, j;
290
291	if (amd_northbridges.num)
292		return 0;
293
294	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
295		root_ids = hygon_root_ids;
296		misc_ids = hygon_nb_misc_ids;
297		link_ids = hygon_nb_link_ids;
298	}
299
300	misc = NULL;
301	while ((misc = next_northbridge(misc, misc_ids)))
302		misc_count++;
303
304	if (!misc_count)
305		return -ENODEV;
306
307	root = NULL;
308	while ((root = next_northbridge(root, root_ids)))
309		root_count++;
310
311	if (root_count) {
312		roots_per_misc = root_count / misc_count;
313
314		/*
315		 * There should be _exactly_ N roots for each DF/SMN
316		 * interface.
317		 */
318		if (!roots_per_misc || (root_count % roots_per_misc)) {
319			pr_info("Unsupported AMD DF/PCI configuration found\n");
320			return -ENODEV;
321		}
322	}
323
324	nb = kcalloc(misc_count, sizeof(struct amd_northbridge), GFP_KERNEL);
325	if (!nb)
326		return -ENOMEM;
327
328	amd_northbridges.nb = nb;
329	amd_northbridges.num = misc_count;
330
331	link = misc = root = NULL;
332	for (i = 0; i < amd_northbridges.num; i++) {
333		node_to_amd_nb(i)->root = root =
334			next_northbridge(root, root_ids);
335		node_to_amd_nb(i)->misc = misc =
336			next_northbridge(misc, misc_ids);
337		node_to_amd_nb(i)->link = link =
338			next_northbridge(link, link_ids);
339
340		/*
341		 * If there are more PCI root devices than data fabric/
342		 * system management network interfaces, then the (N)
343		 * PCI roots per DF/SMN interface are functionally the
344		 * same (for DF/SMN access) and N-1 are redundant.  N-1
345		 * PCI roots should be skipped per DF/SMN interface so
346		 * the following DF/SMN interfaces get mapped to
347		 * correct PCI roots.
348		 */
349		for (j = 1; j < roots_per_misc; j++)
350			root = next_northbridge(root, root_ids);
351	}
352
353	if (amd_gart_present())
354		amd_northbridges.flags |= AMD_NB_GART;
355
356	/*
357	 * Check for L3 cache presence.
358	 */
359	if (!cpuid_edx(0x80000006))
360		return 0;
361
362	/*
363	 * Some CPU families support L3 Cache Index Disable. There are some
364	 * limitations because of E382 and E388 on family 0x10.
365	 */
366	if (boot_cpu_data.x86 == 0x10 &&
367	    boot_cpu_data.x86_model >= 0x8 &&
368	    (boot_cpu_data.x86_model > 0x9 ||
369	     boot_cpu_data.x86_stepping >= 0x1))
370		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
371
372	if (boot_cpu_data.x86 == 0x15)
373		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
374
375	/* L3 cache partitioning is supported on family 0x15 */
376	if (boot_cpu_data.x86 == 0x15)
377		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
378
379	return 0;
380}
 
381
382/*
383 * Ignores subdevice/subvendor but as far as I can figure out
384 * they're useless anyways
385 */
386bool __init early_is_amd_nb(u32 device)
387{
388	const struct pci_device_id *misc_ids = amd_nb_misc_ids;
389	const struct pci_device_id *id;
390	u32 vendor = device & 0xffff;
391
392	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
393	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
394		return false;
395
396	if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
397		misc_ids = hygon_nb_misc_ids;
398
399	device >>= 16;
400	for (id = misc_ids; id->vendor; id++)
401		if (vendor == id->vendor && device == id->device)
402			return true;
403	return false;
404}
405
406struct resource *amd_get_mmconfig_range(struct resource *res)
407{
 
408	u64 base, msr;
409	unsigned int segn_busn_bits;
410
411	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
412	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
413		return NULL;
414
415	/* Assume CPUs from Fam10h have mmconfig, although not all VMs do */
416	if (boot_cpu_data.x86 < 0x10 ||
417	    rdmsrl_safe(MSR_FAM10H_MMIO_CONF_BASE, &msr))
418		return NULL;
419
 
 
 
420	/* mmconfig is not enabled */
421	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
422		return NULL;
423
424	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
425
426	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
427			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
428
429	res->flags = IORESOURCE_MEM;
430	res->start = base;
431	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
432	return res;
433}
434
435int amd_get_subcaches(int cpu)
436{
437	struct pci_dev *link = node_to_amd_nb(topology_amd_node_id(cpu))->link;
438	unsigned int mask;
439
440	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
441		return 0;
442
443	pci_read_config_dword(link, 0x1d4, &mask);
444
445	return (mask >> (4 * cpu_data(cpu).topo.core_id)) & 0xf;
446}
447
448int amd_set_subcaches(int cpu, unsigned long mask)
449{
450	static unsigned int reset, ban;
451	struct amd_northbridge *nb = node_to_amd_nb(topology_amd_node_id(cpu));
452	unsigned int reg;
453	int cuid;
454
455	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
456		return -EINVAL;
457
458	/* if necessary, collect reset state of L3 partitioning and BAN mode */
459	if (reset == 0) {
460		pci_read_config_dword(nb->link, 0x1d4, &reset);
461		pci_read_config_dword(nb->misc, 0x1b8, &ban);
462		ban &= 0x180000;
463	}
464
465	/* deactivate BAN mode if any subcaches are to be disabled */
466	if (mask != 0xf) {
467		pci_read_config_dword(nb->misc, 0x1b8, &reg);
468		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
469	}
470
471	cuid = cpu_data(cpu).topo.core_id;
472	mask <<= 4 * cuid;
473	mask |= (0xf ^ (1 << cuid)) << 26;
474
475	pci_write_config_dword(nb->link, 0x1d4, mask);
476
477	/* reset BAN mode if L3 partitioning returned to reset state */
478	pci_read_config_dword(nb->link, 0x1d4, &reg);
479	if (reg == reset) {
480		pci_read_config_dword(nb->misc, 0x1b8, &reg);
481		reg &= ~0x180000;
482		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
483	}
484
485	return 0;
486}
487
488static void amd_cache_gart(void)
489{
490	u16 i;
491
492	if (!amd_nb_has_feature(AMD_NB_GART))
493		return;
494
495	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
496	if (!flush_words) {
497		amd_northbridges.flags &= ~AMD_NB_GART;
498		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
499		return;
500	}
501
502	for (i = 0; i != amd_northbridges.num; i++)
503		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
504}
505
506void amd_flush_garts(void)
507{
508	int flushed, i;
509	unsigned long flags;
510	static DEFINE_SPINLOCK(gart_lock);
511
512	if (!amd_nb_has_feature(AMD_NB_GART))
513		return;
514
515	/*
516	 * Avoid races between AGP and IOMMU. In theory it's not needed
517	 * but I'm not sure if the hardware won't lose flush requests
518	 * when another is pending. This whole thing is so expensive anyways
519	 * that it doesn't matter to serialize more. -AK
520	 */
521	spin_lock_irqsave(&gart_lock, flags);
522	flushed = 0;
523	for (i = 0; i < amd_northbridges.num; i++) {
524		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
525				       flush_words[i] | 1);
526		flushed++;
527	}
528	for (i = 0; i < amd_northbridges.num; i++) {
529		u32 w;
530		/* Make sure the hardware actually executed the flush*/
531		for (;;) {
532			pci_read_config_dword(node_to_amd_nb(i)->misc,
533					      0x9c, &w);
534			if (!(w & 1))
535				break;
536			cpu_relax();
537		}
538	}
539	spin_unlock_irqrestore(&gart_lock, flags);
540	if (!flushed)
541		pr_notice("nothing to flush?\n");
542}
543EXPORT_SYMBOL_GPL(amd_flush_garts);
544
545static void __fix_erratum_688(void *info)
546{
547#define MSR_AMD64_IC_CFG 0xC0011021
548
549	msr_set_bit(MSR_AMD64_IC_CFG, 3);
550	msr_set_bit(MSR_AMD64_IC_CFG, 14);
551}
552
553/* Apply erratum 688 fix so machines without a BIOS fix work. */
554static __init void fix_erratum_688(void)
555{
556	struct pci_dev *F4;
557	u32 val;
558
559	if (boot_cpu_data.x86 != 0x14)
560		return;
561
562	if (!amd_northbridges.num)
563		return;
564
565	F4 = node_to_amd_nb(0)->link;
566	if (!F4)
567		return;
568
569	if (pci_read_config_dword(F4, 0x164, &val))
570		return;
571
572	if (val & BIT(2))
573		return;
574
575	on_each_cpu(__fix_erratum_688, NULL, 0);
576
577	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
578}
579
580static __init int init_amd_nbs(void)
581{
582	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
583	    boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
584		return 0;
585
586	amd_cache_northbridges();
587	amd_cache_gart();
588
589	fix_erratum_688();
590
591	return 0;
592}
593
594/* This has to go after the PCI subsystem */
595fs_initcall(init_amd_nbs);
v4.17
 
  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 <asm/amd_nb.h>
 15
 16#define PCI_DEVICE_ID_AMD_17H_ROOT	0x1450
 17#define PCI_DEVICE_ID_AMD_17H_M10H_ROOT	0x15d0
 18#define PCI_DEVICE_ID_AMD_17H_DF_F3	0x1463
 19#define PCI_DEVICE_ID_AMD_17H_DF_F4	0x1464
 20#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F3 0x15eb
 21#define PCI_DEVICE_ID_AMD_17H_M10H_DF_F4 0x15ec
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 22
 23/* Protect the PCI config register pairs used for SMN and DF indirect access. */
 24static DEFINE_MUTEX(smn_mutex);
 25
 26static u32 *flush_words;
 27
 28static const struct pci_device_id amd_root_ids[] = {
 29	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
 30	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_ROOT) },
 
 
 
 
 
 
 
 
 
 
 
 
 31	{}
 32};
 33
 34#define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
 35
 36const struct pci_device_id amd_nb_misc_ids[] = {
 37	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
 38	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
 39	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
 40	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
 41	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
 42	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
 43	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
 44	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
 45	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
 46	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F3) },
 
 
 
 47	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 48	{}
 49};
 50EXPORT_SYMBOL_GPL(amd_nb_misc_ids);
 51
 52static const struct pci_device_id amd_nb_link_ids[] = {
 53	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
 54	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
 55	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
 56	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
 57	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
 58	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
 59	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_M10H_DF_F4) },
 
 
 
 
 
 
 
 
 
 
 
 60	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 61	{}
 62};
 63
 64const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
 65	{ 0x00, 0x18, 0x20 },
 66	{ 0xff, 0x00, 0x20 },
 67	{ 0xfe, 0x00, 0x20 },
 68	{ }
 69};
 70
 71static struct amd_northbridge_info amd_northbridges;
 72
 73u16 amd_nb_num(void)
 74{
 75	return amd_northbridges.num;
 76}
 77EXPORT_SYMBOL_GPL(amd_nb_num);
 78
 79bool amd_nb_has_feature(unsigned int feature)
 80{
 81	return ((amd_northbridges.flags & feature) == feature);
 82}
 83EXPORT_SYMBOL_GPL(amd_nb_has_feature);
 84
 85struct amd_northbridge *node_to_amd_nb(int node)
 86{
 87	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
 88}
 89EXPORT_SYMBOL_GPL(node_to_amd_nb);
 90
 91static struct pci_dev *next_northbridge(struct pci_dev *dev,
 92					const struct pci_device_id *ids)
 93{
 94	do {
 95		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
 96		if (!dev)
 97			break;
 98	} while (!pci_match_id(ids, dev));
 99	return dev;
100}
101
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
102static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
103{
104	struct pci_dev *root;
105	int err = -ENODEV;
106
107	if (node >= amd_northbridges.num)
108		goto out;
109
110	root = node_to_amd_nb(node)->root;
111	if (!root)
112		goto out;
113
114	mutex_lock(&smn_mutex);
115
116	err = pci_write_config_dword(root, 0x60, address);
117	if (err) {
118		pr_warn("Error programming SMN address 0x%x.\n", address);
119		goto out_unlock;
120	}
121
122	err = (write ? pci_write_config_dword(root, 0x64, *value)
123		     : pci_read_config_dword(root, 0x64, value));
124	if (err)
125		pr_warn("Error %s SMN address 0x%x.\n",
126			(write ? "writing to" : "reading from"), address);
127
128out_unlock:
129	mutex_unlock(&smn_mutex);
130
131out:
132	return err;
133}
134
135int amd_smn_read(u16 node, u32 address, u32 *value)
136{
137	return __amd_smn_rw(node, address, value, false);
 
 
 
 
 
 
 
138}
139EXPORT_SYMBOL_GPL(amd_smn_read);
140
141int amd_smn_write(u16 node, u32 address, u32 value)
142{
143	return __amd_smn_rw(node, address, &value, true);
144}
145EXPORT_SYMBOL_GPL(amd_smn_write);
146
147/*
148 * Data Fabric Indirect Access uses FICAA/FICAD.
149 *
150 * Fabric Indirect Configuration Access Address (FICAA): Constructed based
151 * on the device's Instance Id and the PCI function and register offset of
152 * the desired register.
153 *
154 * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
155 * and FICAD HI registers but so far we only need the LO register.
156 */
157int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
158{
159	struct pci_dev *F4;
160	u32 ficaa;
161	int err = -ENODEV;
162
163	if (node >= amd_northbridges.num)
164		goto out;
165
166	F4 = node_to_amd_nb(node)->link;
167	if (!F4)
168		goto out;
169
170	ficaa  = 1;
171	ficaa |= reg & 0x3FC;
172	ficaa |= (func & 0x7) << 11;
173	ficaa |= instance_id << 16;
174
175	mutex_lock(&smn_mutex);
176
177	err = pci_write_config_dword(F4, 0x5C, ficaa);
178	if (err) {
179		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
180		goto out_unlock;
181	}
182
183	err = pci_read_config_dword(F4, 0x98, lo);
184	if (err)
185		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
186
187out_unlock:
188	mutex_unlock(&smn_mutex);
189
190out:
191	return err;
192}
193EXPORT_SYMBOL_GPL(amd_df_indirect_read);
194
195int amd_cache_northbridges(void)
196{
197	u16 i = 0;
 
 
 
198	struct amd_northbridge *nb;
199	struct pci_dev *root, *misc, *link;
 
 
 
200
201	if (amd_northbridges.num)
202		return 0;
203
 
 
 
 
 
 
204	misc = NULL;
205	while ((misc = next_northbridge(misc, amd_nb_misc_ids)) != NULL)
206		i++;
207
208	if (!i)
209		return -ENODEV;
210
211	nb = kcalloc(i, sizeof(struct amd_northbridge), GFP_KERNEL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
212	if (!nb)
213		return -ENOMEM;
214
215	amd_northbridges.nb = nb;
216	amd_northbridges.num = i;
217
218	link = misc = root = NULL;
219	for (i = 0; i != amd_northbridges.num; i++) {
220		node_to_amd_nb(i)->root = root =
221			next_northbridge(root, amd_root_ids);
222		node_to_amd_nb(i)->misc = misc =
223			next_northbridge(misc, amd_nb_misc_ids);
224		node_to_amd_nb(i)->link = link =
225			next_northbridge(link, amd_nb_link_ids);
 
 
 
 
 
 
 
 
 
 
 
 
226	}
227
228	if (amd_gart_present())
229		amd_northbridges.flags |= AMD_NB_GART;
230
231	/*
232	 * Check for L3 cache presence.
233	 */
234	if (!cpuid_edx(0x80000006))
235		return 0;
236
237	/*
238	 * Some CPU families support L3 Cache Index Disable. There are some
239	 * limitations because of E382 and E388 on family 0x10.
240	 */
241	if (boot_cpu_data.x86 == 0x10 &&
242	    boot_cpu_data.x86_model >= 0x8 &&
243	    (boot_cpu_data.x86_model > 0x9 ||
244	     boot_cpu_data.x86_stepping >= 0x1))
245		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
246
247	if (boot_cpu_data.x86 == 0x15)
248		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
249
250	/* L3 cache partitioning is supported on family 0x15 */
251	if (boot_cpu_data.x86 == 0x15)
252		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
253
254	return 0;
255}
256EXPORT_SYMBOL_GPL(amd_cache_northbridges);
257
258/*
259 * Ignores subdevice/subvendor but as far as I can figure out
260 * they're useless anyways
261 */
262bool __init early_is_amd_nb(u32 device)
263{
 
264	const struct pci_device_id *id;
265	u32 vendor = device & 0xffff;
266
 
 
 
 
 
 
 
267	device >>= 16;
268	for (id = amd_nb_misc_ids; id->vendor; id++)
269		if (vendor == id->vendor && device == id->device)
270			return true;
271	return false;
272}
273
274struct resource *amd_get_mmconfig_range(struct resource *res)
275{
276	u32 address;
277	u64 base, msr;
278	unsigned int segn_busn_bits;
279
280	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
 
281		return NULL;
282
283	/* assume all cpus from fam10h have mmconfig */
284	if (boot_cpu_data.x86 < 0x10)
 
285		return NULL;
286
287	address = MSR_FAM10H_MMIO_CONF_BASE;
288	rdmsrl(address, msr);
289
290	/* mmconfig is not enabled */
291	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
292		return NULL;
293
294	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
295
296	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
297			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
298
299	res->flags = IORESOURCE_MEM;
300	res->start = base;
301	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
302	return res;
303}
304
305int amd_get_subcaches(int cpu)
306{
307	struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
308	unsigned int mask;
309
310	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
311		return 0;
312
313	pci_read_config_dword(link, 0x1d4, &mask);
314
315	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
316}
317
318int amd_set_subcaches(int cpu, unsigned long mask)
319{
320	static unsigned int reset, ban;
321	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));
322	unsigned int reg;
323	int cuid;
324
325	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
326		return -EINVAL;
327
328	/* if necessary, collect reset state of L3 partitioning and BAN mode */
329	if (reset == 0) {
330		pci_read_config_dword(nb->link, 0x1d4, &reset);
331		pci_read_config_dword(nb->misc, 0x1b8, &ban);
332		ban &= 0x180000;
333	}
334
335	/* deactivate BAN mode if any subcaches are to be disabled */
336	if (mask != 0xf) {
337		pci_read_config_dword(nb->misc, 0x1b8, &reg);
338		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
339	}
340
341	cuid = cpu_data(cpu).cpu_core_id;
342	mask <<= 4 * cuid;
343	mask |= (0xf ^ (1 << cuid)) << 26;
344
345	pci_write_config_dword(nb->link, 0x1d4, mask);
346
347	/* reset BAN mode if L3 partitioning returned to reset state */
348	pci_read_config_dword(nb->link, 0x1d4, &reg);
349	if (reg == reset) {
350		pci_read_config_dword(nb->misc, 0x1b8, &reg);
351		reg &= ~0x180000;
352		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
353	}
354
355	return 0;
356}
357
358static void amd_cache_gart(void)
359{
360	u16 i;
361
362	if (!amd_nb_has_feature(AMD_NB_GART))
363		return;
364
365	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
366	if (!flush_words) {
367		amd_northbridges.flags &= ~AMD_NB_GART;
368		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
369		return;
370	}
371
372	for (i = 0; i != amd_northbridges.num; i++)
373		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
374}
375
376void amd_flush_garts(void)
377{
378	int flushed, i;
379	unsigned long flags;
380	static DEFINE_SPINLOCK(gart_lock);
381
382	if (!amd_nb_has_feature(AMD_NB_GART))
383		return;
384
385	/*
386	 * Avoid races between AGP and IOMMU. In theory it's not needed
387	 * but I'm not sure if the hardware won't lose flush requests
388	 * when another is pending. This whole thing is so expensive anyways
389	 * that it doesn't matter to serialize more. -AK
390	 */
391	spin_lock_irqsave(&gart_lock, flags);
392	flushed = 0;
393	for (i = 0; i < amd_northbridges.num; i++) {
394		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
395				       flush_words[i] | 1);
396		flushed++;
397	}
398	for (i = 0; i < amd_northbridges.num; i++) {
399		u32 w;
400		/* Make sure the hardware actually executed the flush*/
401		for (;;) {
402			pci_read_config_dword(node_to_amd_nb(i)->misc,
403					      0x9c, &w);
404			if (!(w & 1))
405				break;
406			cpu_relax();
407		}
408	}
409	spin_unlock_irqrestore(&gart_lock, flags);
410	if (!flushed)
411		pr_notice("nothing to flush?\n");
412}
413EXPORT_SYMBOL_GPL(amd_flush_garts);
414
415static void __fix_erratum_688(void *info)
416{
417#define MSR_AMD64_IC_CFG 0xC0011021
418
419	msr_set_bit(MSR_AMD64_IC_CFG, 3);
420	msr_set_bit(MSR_AMD64_IC_CFG, 14);
421}
422
423/* Apply erratum 688 fix so machines without a BIOS fix work. */
424static __init void fix_erratum_688(void)
425{
426	struct pci_dev *F4;
427	u32 val;
428
429	if (boot_cpu_data.x86 != 0x14)
430		return;
431
432	if (!amd_northbridges.num)
433		return;
434
435	F4 = node_to_amd_nb(0)->link;
436	if (!F4)
437		return;
438
439	if (pci_read_config_dword(F4, 0x164, &val))
440		return;
441
442	if (val & BIT(2))
443		return;
444
445	on_each_cpu(__fix_erratum_688, NULL, 0);
446
447	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
448}
449
450static __init int init_amd_nbs(void)
451{
 
 
 
 
452	amd_cache_northbridges();
453	amd_cache_gart();
454
455	fix_erratum_688();
456
457	return 0;
458}
459
460/* This has to go after the PCI subsystem */
461fs_initcall(init_amd_nbs);