xref: /linux/arch/x86/kernel/cpu/amd.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 #include <linux/export.h>
2 #include <linux/bitops.h>
3 #include <linux/elf.h>
4 #include <linux/mm.h>
5 
6 #include <linux/io.h>
7 #include <linux/sched.h>
8 #include <asm/processor.h>
9 #include <asm/apic.h>
10 #include <asm/cpu.h>
11 #include <asm/smp.h>
12 #include <asm/pci-direct.h>
13 
14 #ifdef CONFIG_X86_64
15 # include <asm/mmconfig.h>
16 # include <asm/cacheflush.h>
17 #endif
18 
19 #include "cpu.h"
20 
21 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
22 {
23 	u32 gprs[8] = { 0 };
24 	int err;
25 
26 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
27 		  "%s should only be used on K8!\n", __func__);
28 
29 	gprs[1] = msr;
30 	gprs[7] = 0x9c5a203a;
31 
32 	err = rdmsr_safe_regs(gprs);
33 
34 	*p = gprs[0] | ((u64)gprs[2] << 32);
35 
36 	return err;
37 }
38 
39 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
40 {
41 	u32 gprs[8] = { 0 };
42 
43 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
44 		  "%s should only be used on K8!\n", __func__);
45 
46 	gprs[0] = (u32)val;
47 	gprs[1] = msr;
48 	gprs[2] = val >> 32;
49 	gprs[7] = 0x9c5a203a;
50 
51 	return wrmsr_safe_regs(gprs);
52 }
53 
54 /*
55  *	B step AMD K6 before B 9730xxxx have hardware bugs that can cause
56  *	misexecution of code under Linux. Owners of such processors should
57  *	contact AMD for precise details and a CPU swap.
58  *
59  *	See	http://www.multimania.com/poulot/k6bug.html
60  *	and	section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
61  *		(Publication # 21266  Issue Date: August 1998)
62  *
63  *	The following test is erm.. interesting. AMD neglected to up
64  *	the chip setting when fixing the bug but they also tweaked some
65  *	performance at the same time..
66  */
67 
68 extern __visible void vide(void);
69 __asm__(".globl vide\n\t.align 4\nvide: ret");
70 
71 static void init_amd_k5(struct cpuinfo_x86 *c)
72 {
73 #ifdef CONFIG_X86_32
74 /*
75  * General Systems BIOSen alias the cpu frequency registers
76  * of the Elan at 0x000df000. Unfortuantly, one of the Linux
77  * drivers subsequently pokes it, and changes the CPU speed.
78  * Workaround : Remove the unneeded alias.
79  */
80 #define CBAR		(0xfffc) /* Configuration Base Address  (32-bit) */
81 #define CBAR_ENB	(0x80000000)
82 #define CBAR_KEY	(0X000000CB)
83 	if (c->x86_model == 9 || c->x86_model == 10) {
84 		if (inl(CBAR) & CBAR_ENB)
85 			outl(0 | CBAR_KEY, CBAR);
86 	}
87 #endif
88 }
89 
90 static void init_amd_k6(struct cpuinfo_x86 *c)
91 {
92 #ifdef CONFIG_X86_32
93 	u32 l, h;
94 	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
95 
96 	if (c->x86_model < 6) {
97 		/* Based on AMD doc 20734R - June 2000 */
98 		if (c->x86_model == 0) {
99 			clear_cpu_cap(c, X86_FEATURE_APIC);
100 			set_cpu_cap(c, X86_FEATURE_PGE);
101 		}
102 		return;
103 	}
104 
105 	if (c->x86_model == 6 && c->x86_mask == 1) {
106 		const int K6_BUG_LOOP = 1000000;
107 		int n;
108 		void (*f_vide)(void);
109 		unsigned long d, d2;
110 
111 		printk(KERN_INFO "AMD K6 stepping B detected - ");
112 
113 		/*
114 		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
115 		 * calls at the same time.
116 		 */
117 
118 		n = K6_BUG_LOOP;
119 		f_vide = vide;
120 		rdtscl(d);
121 		while (n--)
122 			f_vide();
123 		rdtscl(d2);
124 		d = d2-d;
125 
126 		if (d > 20*K6_BUG_LOOP)
127 			printk(KERN_CONT
128 				"system stability may be impaired when more than 32 MB are used.\n");
129 		else
130 			printk(KERN_CONT "probably OK (after B9730xxxx).\n");
131 	}
132 
133 	/* K6 with old style WHCR */
134 	if (c->x86_model < 8 ||
135 	   (c->x86_model == 8 && c->x86_mask < 8)) {
136 		/* We can only write allocate on the low 508Mb */
137 		if (mbytes > 508)
138 			mbytes = 508;
139 
140 		rdmsr(MSR_K6_WHCR, l, h);
141 		if ((l&0x0000FFFF) == 0) {
142 			unsigned long flags;
143 			l = (1<<0)|((mbytes/4)<<1);
144 			local_irq_save(flags);
145 			wbinvd();
146 			wrmsr(MSR_K6_WHCR, l, h);
147 			local_irq_restore(flags);
148 			printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
149 				mbytes);
150 		}
151 		return;
152 	}
153 
154 	if ((c->x86_model == 8 && c->x86_mask > 7) ||
155 	     c->x86_model == 9 || c->x86_model == 13) {
156 		/* The more serious chips .. */
157 
158 		if (mbytes > 4092)
159 			mbytes = 4092;
160 
161 		rdmsr(MSR_K6_WHCR, l, h);
162 		if ((l&0xFFFF0000) == 0) {
163 			unsigned long flags;
164 			l = ((mbytes>>2)<<22)|(1<<16);
165 			local_irq_save(flags);
166 			wbinvd();
167 			wrmsr(MSR_K6_WHCR, l, h);
168 			local_irq_restore(flags);
169 			printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
170 				mbytes);
171 		}
172 
173 		return;
174 	}
175 
176 	if (c->x86_model == 10) {
177 		/* AMD Geode LX is model 10 */
178 		/* placeholder for any needed mods */
179 		return;
180 	}
181 #endif
182 }
183 
184 static void init_amd_k7(struct cpuinfo_x86 *c)
185 {
186 #ifdef CONFIG_X86_32
187 	u32 l, h;
188 
189 	/*
190 	 * Bit 15 of Athlon specific MSR 15, needs to be 0
191 	 * to enable SSE on Palomino/Morgan/Barton CPU's.
192 	 * If the BIOS didn't enable it already, enable it here.
193 	 */
194 	if (c->x86_model >= 6 && c->x86_model <= 10) {
195 		if (!cpu_has(c, X86_FEATURE_XMM)) {
196 			printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
197 			msr_clear_bit(MSR_K7_HWCR, 15);
198 			set_cpu_cap(c, X86_FEATURE_XMM);
199 		}
200 	}
201 
202 	/*
203 	 * It's been determined by AMD that Athlons since model 8 stepping 1
204 	 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
205 	 * As per AMD technical note 27212 0.2
206 	 */
207 	if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
208 		rdmsr(MSR_K7_CLK_CTL, l, h);
209 		if ((l & 0xfff00000) != 0x20000000) {
210 			printk(KERN_INFO
211 			    "CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
212 					l, ((l & 0x000fffff)|0x20000000));
213 			wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
214 		}
215 	}
216 
217 	set_cpu_cap(c, X86_FEATURE_K7);
218 
219 	/* calling is from identify_secondary_cpu() ? */
220 	if (!c->cpu_index)
221 		return;
222 
223 	/*
224 	 * Certain Athlons might work (for various values of 'work') in SMP
225 	 * but they are not certified as MP capable.
226 	 */
227 	/* Athlon 660/661 is valid. */
228 	if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
229 	    (c->x86_mask == 1)))
230 		return;
231 
232 	/* Duron 670 is valid */
233 	if ((c->x86_model == 7) && (c->x86_mask == 0))
234 		return;
235 
236 	/*
237 	 * Athlon 662, Duron 671, and Athlon >model 7 have capability
238 	 * bit. It's worth noting that the A5 stepping (662) of some
239 	 * Athlon XP's have the MP bit set.
240 	 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
241 	 * more.
242 	 */
243 	if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
244 	    ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
245 	     (c->x86_model > 7))
246 		if (cpu_has(c, X86_FEATURE_MP))
247 			return;
248 
249 	/* If we get here, not a certified SMP capable AMD system. */
250 
251 	/*
252 	 * Don't taint if we are running SMP kernel on a single non-MP
253 	 * approved Athlon
254 	 */
255 	WARN_ONCE(1, "WARNING: This combination of AMD"
256 		" processors is not suitable for SMP.\n");
257 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
258 #endif
259 }
260 
261 #ifdef CONFIG_NUMA
262 /*
263  * To workaround broken NUMA config.  Read the comment in
264  * srat_detect_node().
265  */
266 static int nearby_node(int apicid)
267 {
268 	int i, node;
269 
270 	for (i = apicid - 1; i >= 0; i--) {
271 		node = __apicid_to_node[i];
272 		if (node != NUMA_NO_NODE && node_online(node))
273 			return node;
274 	}
275 	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
276 		node = __apicid_to_node[i];
277 		if (node != NUMA_NO_NODE && node_online(node))
278 			return node;
279 	}
280 	return first_node(node_online_map); /* Shouldn't happen */
281 }
282 #endif
283 
284 /*
285  * Fixup core topology information for
286  * (1) AMD multi-node processors
287  *     Assumption: Number of cores in each internal node is the same.
288  * (2) AMD processors supporting compute units
289  */
290 #ifdef CONFIG_X86_HT
291 static void amd_get_topology(struct cpuinfo_x86 *c)
292 {
293 	u32 nodes, cores_per_cu = 1;
294 	u8 node_id;
295 	int cpu = smp_processor_id();
296 
297 	/* get information required for multi-node processors */
298 	if (cpu_has_topoext) {
299 		u32 eax, ebx, ecx, edx;
300 
301 		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
302 		nodes = ((ecx >> 8) & 7) + 1;
303 		node_id = ecx & 7;
304 
305 		/* get compute unit information */
306 		smp_num_siblings = ((ebx >> 8) & 3) + 1;
307 		c->compute_unit_id = ebx & 0xff;
308 		cores_per_cu += ((ebx >> 8) & 3);
309 	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
310 		u64 value;
311 
312 		rdmsrl(MSR_FAM10H_NODE_ID, value);
313 		nodes = ((value >> 3) & 7) + 1;
314 		node_id = value & 7;
315 	} else
316 		return;
317 
318 	/* fixup multi-node processor information */
319 	if (nodes > 1) {
320 		u32 cores_per_node;
321 		u32 cus_per_node;
322 
323 		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
324 		cores_per_node = c->x86_max_cores / nodes;
325 		cus_per_node = cores_per_node / cores_per_cu;
326 
327 		/* store NodeID, use llc_shared_map to store sibling info */
328 		per_cpu(cpu_llc_id, cpu) = node_id;
329 
330 		/* core id has to be in the [0 .. cores_per_node - 1] range */
331 		c->cpu_core_id %= cores_per_node;
332 		c->compute_unit_id %= cus_per_node;
333 	}
334 }
335 #endif
336 
337 /*
338  * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
339  * Assumes number of cores is a power of two.
340  */
341 static void amd_detect_cmp(struct cpuinfo_x86 *c)
342 {
343 #ifdef CONFIG_X86_HT
344 	unsigned bits;
345 	int cpu = smp_processor_id();
346 
347 	bits = c->x86_coreid_bits;
348 	/* Low order bits define the core id (index of core in socket) */
349 	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
350 	/* Convert the initial APIC ID into the socket ID */
351 	c->phys_proc_id = c->initial_apicid >> bits;
352 	/* use socket ID also for last level cache */
353 	per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
354 	amd_get_topology(c);
355 #endif
356 }
357 
358 u16 amd_get_nb_id(int cpu)
359 {
360 	u16 id = 0;
361 #ifdef CONFIG_SMP
362 	id = per_cpu(cpu_llc_id, cpu);
363 #endif
364 	return id;
365 }
366 EXPORT_SYMBOL_GPL(amd_get_nb_id);
367 
368 static void srat_detect_node(struct cpuinfo_x86 *c)
369 {
370 #ifdef CONFIG_NUMA
371 	int cpu = smp_processor_id();
372 	int node;
373 	unsigned apicid = c->apicid;
374 
375 	node = numa_cpu_node(cpu);
376 	if (node == NUMA_NO_NODE)
377 		node = per_cpu(cpu_llc_id, cpu);
378 
379 	/*
380 	 * On multi-fabric platform (e.g. Numascale NumaChip) a
381 	 * platform-specific handler needs to be called to fixup some
382 	 * IDs of the CPU.
383 	 */
384 	if (x86_cpuinit.fixup_cpu_id)
385 		x86_cpuinit.fixup_cpu_id(c, node);
386 
387 	if (!node_online(node)) {
388 		/*
389 		 * Two possibilities here:
390 		 *
391 		 * - The CPU is missing memory and no node was created.  In
392 		 *   that case try picking one from a nearby CPU.
393 		 *
394 		 * - The APIC IDs differ from the HyperTransport node IDs
395 		 *   which the K8 northbridge parsing fills in.  Assume
396 		 *   they are all increased by a constant offset, but in
397 		 *   the same order as the HT nodeids.  If that doesn't
398 		 *   result in a usable node fall back to the path for the
399 		 *   previous case.
400 		 *
401 		 * This workaround operates directly on the mapping between
402 		 * APIC ID and NUMA node, assuming certain relationship
403 		 * between APIC ID, HT node ID and NUMA topology.  As going
404 		 * through CPU mapping may alter the outcome, directly
405 		 * access __apicid_to_node[].
406 		 */
407 		int ht_nodeid = c->initial_apicid;
408 
409 		if (ht_nodeid >= 0 &&
410 		    __apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
411 			node = __apicid_to_node[ht_nodeid];
412 		/* Pick a nearby node */
413 		if (!node_online(node))
414 			node = nearby_node(apicid);
415 	}
416 	numa_set_node(cpu, node);
417 #endif
418 }
419 
420 static void early_init_amd_mc(struct cpuinfo_x86 *c)
421 {
422 #ifdef CONFIG_X86_HT
423 	unsigned bits, ecx;
424 
425 	/* Multi core CPU? */
426 	if (c->extended_cpuid_level < 0x80000008)
427 		return;
428 
429 	ecx = cpuid_ecx(0x80000008);
430 
431 	c->x86_max_cores = (ecx & 0xff) + 1;
432 
433 	/* CPU telling us the core id bits shift? */
434 	bits = (ecx >> 12) & 0xF;
435 
436 	/* Otherwise recompute */
437 	if (bits == 0) {
438 		while ((1 << bits) < c->x86_max_cores)
439 			bits++;
440 	}
441 
442 	c->x86_coreid_bits = bits;
443 #endif
444 }
445 
446 static void bsp_init_amd(struct cpuinfo_x86 *c)
447 {
448 
449 #ifdef CONFIG_X86_64
450 	if (c->x86 >= 0xf) {
451 		unsigned long long tseg;
452 
453 		/*
454 		 * Split up direct mapping around the TSEG SMM area.
455 		 * Don't do it for gbpages because there seems very little
456 		 * benefit in doing so.
457 		 */
458 		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
459 			unsigned long pfn = tseg >> PAGE_SHIFT;
460 
461 			printk(KERN_DEBUG "tseg: %010llx\n", tseg);
462 			if (pfn_range_is_mapped(pfn, pfn + 1))
463 				set_memory_4k((unsigned long)__va(tseg), 1);
464 		}
465 	}
466 #endif
467 
468 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
469 
470 		if (c->x86 > 0x10 ||
471 		    (c->x86 == 0x10 && c->x86_model >= 0x2)) {
472 			u64 val;
473 
474 			rdmsrl(MSR_K7_HWCR, val);
475 			if (!(val & BIT(24)))
476 				printk(KERN_WARNING FW_BUG "TSC doesn't count "
477 					"with P0 frequency!\n");
478 		}
479 	}
480 
481 	if (c->x86 == 0x15) {
482 		unsigned long upperbit;
483 		u32 cpuid, assoc;
484 
485 		cpuid	 = cpuid_edx(0x80000005);
486 		assoc	 = cpuid >> 16 & 0xff;
487 		upperbit = ((cpuid >> 24) << 10) / assoc;
488 
489 		va_align.mask	  = (upperbit - 1) & PAGE_MASK;
490 		va_align.flags    = ALIGN_VA_32 | ALIGN_VA_64;
491 	}
492 }
493 
494 static void early_init_amd(struct cpuinfo_x86 *c)
495 {
496 	early_init_amd_mc(c);
497 
498 	/*
499 	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
500 	 * with P/T states and does not stop in deep C-states
501 	 */
502 	if (c->x86_power & (1 << 8)) {
503 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
504 		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
505 		if (!check_tsc_unstable())
506 			set_sched_clock_stable();
507 	}
508 
509 #ifdef CONFIG_X86_64
510 	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
511 #else
512 	/*  Set MTRR capability flag if appropriate */
513 	if (c->x86 == 5)
514 		if (c->x86_model == 13 || c->x86_model == 9 ||
515 		    (c->x86_model == 8 && c->x86_mask >= 8))
516 			set_cpu_cap(c, X86_FEATURE_K6_MTRR);
517 #endif
518 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
519 	/* check CPU config space for extended APIC ID */
520 	if (cpu_has_apic && c->x86 >= 0xf) {
521 		unsigned int val;
522 		val = read_pci_config(0, 24, 0, 0x68);
523 		if ((val & ((1 << 17) | (1 << 18))) == ((1 << 17) | (1 << 18)))
524 			set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
525 	}
526 #endif
527 
528 	/*
529 	 * This is only needed to tell the kernel whether to use VMCALL
530 	 * and VMMCALL.  VMMCALL is never executed except under virt, so
531 	 * we can set it unconditionally.
532 	 */
533 	set_cpu_cap(c, X86_FEATURE_VMMCALL);
534 
535 	/* F16h erratum 793, CVE-2013-6885 */
536 	if (c->x86 == 0x16 && c->x86_model <= 0xf)
537 		msr_set_bit(MSR_AMD64_LS_CFG, 15);
538 }
539 
540 static const int amd_erratum_383[];
541 static const int amd_erratum_400[];
542 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
543 
544 static void init_amd_k8(struct cpuinfo_x86 *c)
545 {
546 	u32 level;
547 	u64 value;
548 
549 	/* On C+ stepping K8 rep microcode works well for copy/memset */
550 	level = cpuid_eax(1);
551 	if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
552 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
553 
554 	/*
555 	 * Some BIOSes incorrectly force this feature, but only K8 revision D
556 	 * (model = 0x14) and later actually support it.
557 	 * (AMD Erratum #110, docId: 25759).
558 	 */
559 	if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
560 		clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
561 		if (!rdmsrl_amd_safe(0xc001100d, &value)) {
562 			value &= ~BIT_64(32);
563 			wrmsrl_amd_safe(0xc001100d, value);
564 		}
565 	}
566 
567 	if (!c->x86_model_id[0])
568 		strcpy(c->x86_model_id, "Hammer");
569 
570 #ifdef CONFIG_SMP
571 	/*
572 	 * Disable TLB flush filter by setting HWCR.FFDIS on K8
573 	 * bit 6 of msr C001_0015
574 	 *
575 	 * Errata 63 for SH-B3 steppings
576 	 * Errata 122 for all steppings (F+ have it disabled by default)
577 	 */
578 	msr_set_bit(MSR_K7_HWCR, 6);
579 #endif
580 }
581 
582 static void init_amd_gh(struct cpuinfo_x86 *c)
583 {
584 #ifdef CONFIG_X86_64
585 	/* do this for boot cpu */
586 	if (c == &boot_cpu_data)
587 		check_enable_amd_mmconf_dmi();
588 
589 	fam10h_check_enable_mmcfg();
590 #endif
591 
592 	/*
593 	 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
594 	 * is always needed when GART is enabled, even in a kernel which has no
595 	 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
596 	 * If it doesn't, we do it here as suggested by the BKDG.
597 	 *
598 	 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
599 	 */
600 	msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
601 
602 	/*
603 	 * On family 10h BIOS may not have properly enabled WC+ support, causing
604 	 * it to be converted to CD memtype. This may result in performance
605 	 * degradation for certain nested-paging guests. Prevent this conversion
606 	 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
607 	 *
608 	 * NOTE: we want to use the _safe accessors so as not to #GP kvm
609 	 * guests on older kvm hosts.
610 	 */
611 	msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
612 
613 	if (cpu_has_amd_erratum(c, amd_erratum_383))
614 		set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
615 }
616 
617 static void init_amd_bd(struct cpuinfo_x86 *c)
618 {
619 	u64 value;
620 
621 	/* re-enable TopologyExtensions if switched off by BIOS */
622 	if ((c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
623 	    !cpu_has(c, X86_FEATURE_TOPOEXT)) {
624 
625 		if (msr_set_bit(0xc0011005, 54) > 0) {
626 			rdmsrl(0xc0011005, value);
627 			if (value & BIT_64(54)) {
628 				set_cpu_cap(c, X86_FEATURE_TOPOEXT);
629 				pr_info(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
630 			}
631 		}
632 	}
633 
634 	/*
635 	 * The way access filter has a performance penalty on some workloads.
636 	 * Disable it on the affected CPUs.
637 	 */
638 	if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
639 		if (!rdmsrl_safe(0xc0011021, &value) && !(value & 0x1E)) {
640 			value |= 0x1E;
641 			wrmsrl_safe(0xc0011021, value);
642 		}
643 	}
644 }
645 
646 static void init_amd(struct cpuinfo_x86 *c)
647 {
648 	u32 dummy;
649 
650 	early_init_amd(c);
651 
652 	/*
653 	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
654 	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
655 	 */
656 	clear_cpu_cap(c, 0*32+31);
657 
658 	if (c->x86 >= 0x10)
659 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
660 
661 	/* get apicid instead of initial apic id from cpuid */
662 	c->apicid = hard_smp_processor_id();
663 
664 	/* K6s reports MCEs but don't actually have all the MSRs */
665 	if (c->x86 < 6)
666 		clear_cpu_cap(c, X86_FEATURE_MCE);
667 
668 	switch (c->x86) {
669 	case 4:    init_amd_k5(c); break;
670 	case 5:    init_amd_k6(c); break;
671 	case 6:	   init_amd_k7(c); break;
672 	case 0xf:  init_amd_k8(c); break;
673 	case 0x10: init_amd_gh(c); break;
674 	case 0x15: init_amd_bd(c); break;
675 	}
676 
677 	/* Enable workaround for FXSAVE leak */
678 	if (c->x86 >= 6)
679 		set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
680 
681 	cpu_detect_cache_sizes(c);
682 
683 	/* Multi core CPU? */
684 	if (c->extended_cpuid_level >= 0x80000008) {
685 		amd_detect_cmp(c);
686 		srat_detect_node(c);
687 	}
688 
689 #ifdef CONFIG_X86_32
690 	detect_ht(c);
691 #endif
692 
693 	init_amd_cacheinfo(c);
694 
695 	if (c->x86 >= 0xf)
696 		set_cpu_cap(c, X86_FEATURE_K8);
697 
698 	if (cpu_has_xmm2) {
699 		/* MFENCE stops RDTSC speculation */
700 		set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
701 	}
702 
703 	/*
704 	 * Family 0x12 and above processors have APIC timer
705 	 * running in deep C states.
706 	 */
707 	if (c->x86 > 0x11)
708 		set_cpu_cap(c, X86_FEATURE_ARAT);
709 
710 	if (cpu_has_amd_erratum(c, amd_erratum_400))
711 		set_cpu_bug(c, X86_BUG_AMD_APIC_C1E);
712 
713 	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
714 }
715 
716 #ifdef CONFIG_X86_32
717 static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
718 {
719 	/* AMD errata T13 (order #21922) */
720 	if ((c->x86 == 6)) {
721 		/* Duron Rev A0 */
722 		if (c->x86_model == 3 && c->x86_mask == 0)
723 			size = 64;
724 		/* Tbird rev A1/A2 */
725 		if (c->x86_model == 4 &&
726 			(c->x86_mask == 0 || c->x86_mask == 1))
727 			size = 256;
728 	}
729 	return size;
730 }
731 #endif
732 
733 static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
734 {
735 	u32 ebx, eax, ecx, edx;
736 	u16 mask = 0xfff;
737 
738 	if (c->x86 < 0xf)
739 		return;
740 
741 	if (c->extended_cpuid_level < 0x80000006)
742 		return;
743 
744 	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
745 
746 	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
747 	tlb_lli_4k[ENTRIES] = ebx & mask;
748 
749 	/*
750 	 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
751 	 * characteristics from the CPUID function 0x80000005 instead.
752 	 */
753 	if (c->x86 == 0xf) {
754 		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
755 		mask = 0xff;
756 	}
757 
758 	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
759 	if (!((eax >> 16) & mask))
760 		tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
761 	else
762 		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
763 
764 	/* a 4M entry uses two 2M entries */
765 	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
766 
767 	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
768 	if (!(eax & mask)) {
769 		/* Erratum 658 */
770 		if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
771 			tlb_lli_2m[ENTRIES] = 1024;
772 		} else {
773 			cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
774 			tlb_lli_2m[ENTRIES] = eax & 0xff;
775 		}
776 	} else
777 		tlb_lli_2m[ENTRIES] = eax & mask;
778 
779 	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
780 }
781 
782 static const struct cpu_dev amd_cpu_dev = {
783 	.c_vendor	= "AMD",
784 	.c_ident	= { "AuthenticAMD" },
785 #ifdef CONFIG_X86_32
786 	.legacy_models = {
787 		{ .family = 4, .model_names =
788 		  {
789 			  [3] = "486 DX/2",
790 			  [7] = "486 DX/2-WB",
791 			  [8] = "486 DX/4",
792 			  [9] = "486 DX/4-WB",
793 			  [14] = "Am5x86-WT",
794 			  [15] = "Am5x86-WB"
795 		  }
796 		},
797 	},
798 	.legacy_cache_size = amd_size_cache,
799 #endif
800 	.c_early_init   = early_init_amd,
801 	.c_detect_tlb	= cpu_detect_tlb_amd,
802 	.c_bsp_init	= bsp_init_amd,
803 	.c_init		= init_amd,
804 	.c_x86_vendor	= X86_VENDOR_AMD,
805 };
806 
807 cpu_dev_register(amd_cpu_dev);
808 
809 /*
810  * AMD errata checking
811  *
812  * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
813  * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
814  * have an OSVW id assigned, which it takes as first argument. Both take a
815  * variable number of family-specific model-stepping ranges created by
816  * AMD_MODEL_RANGE().
817  *
818  * Example:
819  *
820  * const int amd_erratum_319[] =
821  *	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
822  *			   AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
823  *			   AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
824  */
825 
826 #define AMD_LEGACY_ERRATUM(...)		{ -1, __VA_ARGS__, 0 }
827 #define AMD_OSVW_ERRATUM(osvw_id, ...)	{ osvw_id, __VA_ARGS__, 0 }
828 #define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
829 	((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
830 #define AMD_MODEL_RANGE_FAMILY(range)	(((range) >> 24) & 0xff)
831 #define AMD_MODEL_RANGE_START(range)	(((range) >> 12) & 0xfff)
832 #define AMD_MODEL_RANGE_END(range)	((range) & 0xfff)
833 
834 static const int amd_erratum_400[] =
835 	AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
836 			    AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
837 
838 static const int amd_erratum_383[] =
839 	AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
840 
841 
842 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
843 {
844 	int osvw_id = *erratum++;
845 	u32 range;
846 	u32 ms;
847 
848 	if (osvw_id >= 0 && osvw_id < 65536 &&
849 	    cpu_has(cpu, X86_FEATURE_OSVW)) {
850 		u64 osvw_len;
851 
852 		rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
853 		if (osvw_id < osvw_len) {
854 			u64 osvw_bits;
855 
856 			rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
857 			    osvw_bits);
858 			return osvw_bits & (1ULL << (osvw_id & 0x3f));
859 		}
860 	}
861 
862 	/* OSVW unavailable or ID unknown, match family-model-stepping range */
863 	ms = (cpu->x86_model << 4) | cpu->x86_mask;
864 	while ((range = *erratum++))
865 		if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
866 		    (ms >= AMD_MODEL_RANGE_START(range)) &&
867 		    (ms <= AMD_MODEL_RANGE_END(range)))
868 			return true;
869 
870 	return false;
871 }
872 
873 void set_dr_addr_mask(unsigned long mask, int dr)
874 {
875 	if (!cpu_has_bpext)
876 		return;
877 
878 	switch (dr) {
879 	case 0:
880 		wrmsr(MSR_F16H_DR0_ADDR_MASK, mask, 0);
881 		break;
882 	case 1:
883 	case 2:
884 	case 3:
885 		wrmsr(MSR_F16H_DR1_ADDR_MASK - 1 + dr, mask, 0);
886 		break;
887 	default:
888 		break;
889 	}
890 }
891