xref: /openbmc/linux/arch/x86/kernel/amd_nb.c (revision e3b9f1e8)
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_DF_F3	0x1463
18 #define PCI_DEVICE_ID_AMD_17H_DF_F4	0x1464
19 
20 /* Protect the PCI config register pairs used for SMN and DF indirect access. */
21 static DEFINE_MUTEX(smn_mutex);
22 
23 static u32 *flush_words;
24 
25 static const struct pci_device_id amd_root_ids[] = {
26 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_ROOT) },
27 	{}
28 };
29 
30 #define PCI_DEVICE_ID_AMD_CNB17H_F4     0x1704
31 
32 const struct pci_device_id amd_nb_misc_ids[] = {
33 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
34 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
35 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F3) },
36 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M10H_F3) },
37 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F3) },
38 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F3) },
39 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F3) },
40 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F3) },
41 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F3) },
42 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F3) },
43 	{}
44 };
45 EXPORT_SYMBOL_GPL(amd_nb_misc_ids);
46 
47 static const struct pci_device_id amd_nb_link_ids[] = {
48 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_F4) },
49 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M30H_NB_F4) },
50 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_M60H_NB_F4) },
51 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_NB_F4) },
52 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_16H_M30H_NB_F4) },
53 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_17H_DF_F4) },
54 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CNB17H_F4) },
55 	{}
56 };
57 
58 const struct amd_nb_bus_dev_range amd_nb_bus_dev_ranges[] __initconst = {
59 	{ 0x00, 0x18, 0x20 },
60 	{ 0xff, 0x00, 0x20 },
61 	{ 0xfe, 0x00, 0x20 },
62 	{ }
63 };
64 
65 static struct amd_northbridge_info amd_northbridges;
66 
67 u16 amd_nb_num(void)
68 {
69 	return amd_northbridges.num;
70 }
71 EXPORT_SYMBOL_GPL(amd_nb_num);
72 
73 bool amd_nb_has_feature(unsigned int feature)
74 {
75 	return ((amd_northbridges.flags & feature) == feature);
76 }
77 EXPORT_SYMBOL_GPL(amd_nb_has_feature);
78 
79 struct amd_northbridge *node_to_amd_nb(int node)
80 {
81 	return (node < amd_northbridges.num) ? &amd_northbridges.nb[node] : NULL;
82 }
83 EXPORT_SYMBOL_GPL(node_to_amd_nb);
84 
85 static struct pci_dev *next_northbridge(struct pci_dev *dev,
86 					const struct pci_device_id *ids)
87 {
88 	do {
89 		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
90 		if (!dev)
91 			break;
92 	} while (!pci_match_id(ids, dev));
93 	return dev;
94 }
95 
96 static int __amd_smn_rw(u16 node, u32 address, u32 *value, bool write)
97 {
98 	struct pci_dev *root;
99 	int err = -ENODEV;
100 
101 	if (node >= amd_northbridges.num)
102 		goto out;
103 
104 	root = node_to_amd_nb(node)->root;
105 	if (!root)
106 		goto out;
107 
108 	mutex_lock(&smn_mutex);
109 
110 	err = pci_write_config_dword(root, 0x60, address);
111 	if (err) {
112 		pr_warn("Error programming SMN address 0x%x.\n", address);
113 		goto out_unlock;
114 	}
115 
116 	err = (write ? pci_write_config_dword(root, 0x64, *value)
117 		     : pci_read_config_dword(root, 0x64, value));
118 	if (err)
119 		pr_warn("Error %s SMN address 0x%x.\n",
120 			(write ? "writing to" : "reading from"), address);
121 
122 out_unlock:
123 	mutex_unlock(&smn_mutex);
124 
125 out:
126 	return err;
127 }
128 
129 int amd_smn_read(u16 node, u32 address, u32 *value)
130 {
131 	return __amd_smn_rw(node, address, value, false);
132 }
133 EXPORT_SYMBOL_GPL(amd_smn_read);
134 
135 int amd_smn_write(u16 node, u32 address, u32 value)
136 {
137 	return __amd_smn_rw(node, address, &value, true);
138 }
139 EXPORT_SYMBOL_GPL(amd_smn_write);
140 
141 /*
142  * Data Fabric Indirect Access uses FICAA/FICAD.
143  *
144  * Fabric Indirect Configuration Access Address (FICAA): Constructed based
145  * on the device's Instance Id and the PCI function and register offset of
146  * the desired register.
147  *
148  * Fabric Indirect Configuration Access Data (FICAD): There are FICAD LO
149  * and FICAD HI registers but so far we only need the LO register.
150  */
151 int amd_df_indirect_read(u16 node, u8 func, u16 reg, u8 instance_id, u32 *lo)
152 {
153 	struct pci_dev *F4;
154 	u32 ficaa;
155 	int err = -ENODEV;
156 
157 	if (node >= amd_northbridges.num)
158 		goto out;
159 
160 	F4 = node_to_amd_nb(node)->link;
161 	if (!F4)
162 		goto out;
163 
164 	ficaa  = 1;
165 	ficaa |= reg & 0x3FC;
166 	ficaa |= (func & 0x7) << 11;
167 	ficaa |= instance_id << 16;
168 
169 	mutex_lock(&smn_mutex);
170 
171 	err = pci_write_config_dword(F4, 0x5C, ficaa);
172 	if (err) {
173 		pr_warn("Error writing DF Indirect FICAA, FICAA=0x%x\n", ficaa);
174 		goto out_unlock;
175 	}
176 
177 	err = pci_read_config_dword(F4, 0x98, lo);
178 	if (err)
179 		pr_warn("Error reading DF Indirect FICAD LO, FICAA=0x%x.\n", ficaa);
180 
181 out_unlock:
182 	mutex_unlock(&smn_mutex);
183 
184 out:
185 	return err;
186 }
187 EXPORT_SYMBOL_GPL(amd_df_indirect_read);
188 
189 int amd_cache_northbridges(void)
190 {
191 	u16 i = 0;
192 	struct amd_northbridge *nb;
193 	struct pci_dev *root, *misc, *link;
194 
195 	if (amd_northbridges.num)
196 		return 0;
197 
198 	misc = NULL;
199 	while ((misc = next_northbridge(misc, amd_nb_misc_ids)) != NULL)
200 		i++;
201 
202 	if (!i)
203 		return -ENODEV;
204 
205 	nb = kcalloc(i, sizeof(struct amd_northbridge), GFP_KERNEL);
206 	if (!nb)
207 		return -ENOMEM;
208 
209 	amd_northbridges.nb = nb;
210 	amd_northbridges.num = i;
211 
212 	link = misc = root = NULL;
213 	for (i = 0; i != amd_northbridges.num; i++) {
214 		node_to_amd_nb(i)->root = root =
215 			next_northbridge(root, amd_root_ids);
216 		node_to_amd_nb(i)->misc = misc =
217 			next_northbridge(misc, amd_nb_misc_ids);
218 		node_to_amd_nb(i)->link = link =
219 			next_northbridge(link, amd_nb_link_ids);
220 	}
221 
222 	if (amd_gart_present())
223 		amd_northbridges.flags |= AMD_NB_GART;
224 
225 	/*
226 	 * Check for L3 cache presence.
227 	 */
228 	if (!cpuid_edx(0x80000006))
229 		return 0;
230 
231 	/*
232 	 * Some CPU families support L3 Cache Index Disable. There are some
233 	 * limitations because of E382 and E388 on family 0x10.
234 	 */
235 	if (boot_cpu_data.x86 == 0x10 &&
236 	    boot_cpu_data.x86_model >= 0x8 &&
237 	    (boot_cpu_data.x86_model > 0x9 ||
238 	     boot_cpu_data.x86_stepping >= 0x1))
239 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
240 
241 	if (boot_cpu_data.x86 == 0x15)
242 		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;
243 
244 	/* L3 cache partitioning is supported on family 0x15 */
245 	if (boot_cpu_data.x86 == 0x15)
246 		amd_northbridges.flags |= AMD_NB_L3_PARTITIONING;
247 
248 	return 0;
249 }
250 EXPORT_SYMBOL_GPL(amd_cache_northbridges);
251 
252 /*
253  * Ignores subdevice/subvendor but as far as I can figure out
254  * they're useless anyways
255  */
256 bool __init early_is_amd_nb(u32 device)
257 {
258 	const struct pci_device_id *id;
259 	u32 vendor = device & 0xffff;
260 
261 	device >>= 16;
262 	for (id = amd_nb_misc_ids; id->vendor; id++)
263 		if (vendor == id->vendor && device == id->device)
264 			return true;
265 	return false;
266 }
267 
268 struct resource *amd_get_mmconfig_range(struct resource *res)
269 {
270 	u32 address;
271 	u64 base, msr;
272 	unsigned int segn_busn_bits;
273 
274 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
275 		return NULL;
276 
277 	/* assume all cpus from fam10h have mmconfig */
278 	if (boot_cpu_data.x86 < 0x10)
279 		return NULL;
280 
281 	address = MSR_FAM10H_MMIO_CONF_BASE;
282 	rdmsrl(address, msr);
283 
284 	/* mmconfig is not enabled */
285 	if (!(msr & FAM10H_MMIO_CONF_ENABLE))
286 		return NULL;
287 
288 	base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
289 
290 	segn_busn_bits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
291 			 FAM10H_MMIO_CONF_BUSRANGE_MASK;
292 
293 	res->flags = IORESOURCE_MEM;
294 	res->start = base;
295 	res->end = base + (1ULL<<(segn_busn_bits + 20)) - 1;
296 	return res;
297 }
298 
299 int amd_get_subcaches(int cpu)
300 {
301 	struct pci_dev *link = node_to_amd_nb(amd_get_nb_id(cpu))->link;
302 	unsigned int mask;
303 
304 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
305 		return 0;
306 
307 	pci_read_config_dword(link, 0x1d4, &mask);
308 
309 	return (mask >> (4 * cpu_data(cpu).cpu_core_id)) & 0xf;
310 }
311 
312 int amd_set_subcaches(int cpu, unsigned long mask)
313 {
314 	static unsigned int reset, ban;
315 	struct amd_northbridge *nb = node_to_amd_nb(amd_get_nb_id(cpu));
316 	unsigned int reg;
317 	int cuid;
318 
319 	if (!amd_nb_has_feature(AMD_NB_L3_PARTITIONING) || mask > 0xf)
320 		return -EINVAL;
321 
322 	/* if necessary, collect reset state of L3 partitioning and BAN mode */
323 	if (reset == 0) {
324 		pci_read_config_dword(nb->link, 0x1d4, &reset);
325 		pci_read_config_dword(nb->misc, 0x1b8, &ban);
326 		ban &= 0x180000;
327 	}
328 
329 	/* deactivate BAN mode if any subcaches are to be disabled */
330 	if (mask != 0xf) {
331 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
332 		pci_write_config_dword(nb->misc, 0x1b8, reg & ~0x180000);
333 	}
334 
335 	cuid = cpu_data(cpu).cpu_core_id;
336 	mask <<= 4 * cuid;
337 	mask |= (0xf ^ (1 << cuid)) << 26;
338 
339 	pci_write_config_dword(nb->link, 0x1d4, mask);
340 
341 	/* reset BAN mode if L3 partitioning returned to reset state */
342 	pci_read_config_dword(nb->link, 0x1d4, &reg);
343 	if (reg == reset) {
344 		pci_read_config_dword(nb->misc, 0x1b8, &reg);
345 		reg &= ~0x180000;
346 		pci_write_config_dword(nb->misc, 0x1b8, reg | ban);
347 	}
348 
349 	return 0;
350 }
351 
352 static void amd_cache_gart(void)
353 {
354 	u16 i;
355 
356 	if (!amd_nb_has_feature(AMD_NB_GART))
357 		return;
358 
359 	flush_words = kmalloc_array(amd_northbridges.num, sizeof(u32), GFP_KERNEL);
360 	if (!flush_words) {
361 		amd_northbridges.flags &= ~AMD_NB_GART;
362 		pr_notice("Cannot initialize GART flush words, GART support disabled\n");
363 		return;
364 	}
365 
366 	for (i = 0; i != amd_northbridges.num; i++)
367 		pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c, &flush_words[i]);
368 }
369 
370 void amd_flush_garts(void)
371 {
372 	int flushed, i;
373 	unsigned long flags;
374 	static DEFINE_SPINLOCK(gart_lock);
375 
376 	if (!amd_nb_has_feature(AMD_NB_GART))
377 		return;
378 
379 	/*
380 	 * Avoid races between AGP and IOMMU. In theory it's not needed
381 	 * but I'm not sure if the hardware won't lose flush requests
382 	 * when another is pending. This whole thing is so expensive anyways
383 	 * that it doesn't matter to serialize more. -AK
384 	 */
385 	spin_lock_irqsave(&gart_lock, flags);
386 	flushed = 0;
387 	for (i = 0; i < amd_northbridges.num; i++) {
388 		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
389 				       flush_words[i] | 1);
390 		flushed++;
391 	}
392 	for (i = 0; i < amd_northbridges.num; i++) {
393 		u32 w;
394 		/* Make sure the hardware actually executed the flush*/
395 		for (;;) {
396 			pci_read_config_dword(node_to_amd_nb(i)->misc,
397 					      0x9c, &w);
398 			if (!(w & 1))
399 				break;
400 			cpu_relax();
401 		}
402 	}
403 	spin_unlock_irqrestore(&gart_lock, flags);
404 	if (!flushed)
405 		pr_notice("nothing to flush?\n");
406 }
407 EXPORT_SYMBOL_GPL(amd_flush_garts);
408 
409 static void __fix_erratum_688(void *info)
410 {
411 #define MSR_AMD64_IC_CFG 0xC0011021
412 
413 	msr_set_bit(MSR_AMD64_IC_CFG, 3);
414 	msr_set_bit(MSR_AMD64_IC_CFG, 14);
415 }
416 
417 /* Apply erratum 688 fix so machines without a BIOS fix work. */
418 static __init void fix_erratum_688(void)
419 {
420 	struct pci_dev *F4;
421 	u32 val;
422 
423 	if (boot_cpu_data.x86 != 0x14)
424 		return;
425 
426 	if (!amd_northbridges.num)
427 		return;
428 
429 	F4 = node_to_amd_nb(0)->link;
430 	if (!F4)
431 		return;
432 
433 	if (pci_read_config_dword(F4, 0x164, &val))
434 		return;
435 
436 	if (val & BIT(2))
437 		return;
438 
439 	on_each_cpu(__fix_erratum_688, NULL, 0);
440 
441 	pr_info("x86/cpu/AMD: CPU erratum 688 worked around\n");
442 }
443 
444 static __init int init_amd_nbs(void)
445 {
446 	amd_cache_northbridges();
447 	amd_cache_gart();
448 
449 	fix_erratum_688();
450 
451 	return 0;
452 }
453 
454 /* This has to go after the PCI subsystem */
455 fs_initcall(init_amd_nbs);
456