xref: /linux/arch/x86/kernel/cpu/amd.c (revision 1698872b5c772aebc5c43ca445cc0a79f12b9fcc)
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 <linux/random.h>
9 #include <asm/processor.h>
10 #include <asm/apic.h>
11 #include <asm/cpu.h>
12 #include <asm/smp.h>
13 #include <asm/pci-direct.h>
14 #include <asm/delay.h>
15 
16 #ifdef CONFIG_X86_64
17 # include <asm/mmconfig.h>
18 # include <asm/cacheflush.h>
19 #endif
20 
21 #include "cpu.h"
22 
23 /*
24  * nodes_per_socket: Stores the number of nodes per socket.
25  * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
26  * Node Identifiers[10:8]
27  */
28 static u32 nodes_per_socket = 1;
29 
30 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
31 {
32 	u32 gprs[8] = { 0 };
33 	int err;
34 
35 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
36 		  "%s should only be used on K8!\n", __func__);
37 
38 	gprs[1] = msr;
39 	gprs[7] = 0x9c5a203a;
40 
41 	err = rdmsr_safe_regs(gprs);
42 
43 	*p = gprs[0] | ((u64)gprs[2] << 32);
44 
45 	return err;
46 }
47 
48 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
49 {
50 	u32 gprs[8] = { 0 };
51 
52 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
53 		  "%s should only be used on K8!\n", __func__);
54 
55 	gprs[0] = (u32)val;
56 	gprs[1] = msr;
57 	gprs[2] = val >> 32;
58 	gprs[7] = 0x9c5a203a;
59 
60 	return wrmsr_safe_regs(gprs);
61 }
62 
63 /*
64  *	B step AMD K6 before B 9730xxxx have hardware bugs that can cause
65  *	misexecution of code under Linux. Owners of such processors should
66  *	contact AMD for precise details and a CPU swap.
67  *
68  *	See	http://www.multimania.com/poulot/k6bug.html
69  *	and	section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
70  *		(Publication # 21266  Issue Date: August 1998)
71  *
72  *	The following test is erm.. interesting. AMD neglected to up
73  *	the chip setting when fixing the bug but they also tweaked some
74  *	performance at the same time..
75  */
76 
77 extern __visible void vide(void);
78 __asm__(".globl vide\n"
79 	".type vide, @function\n"
80 	".align 4\n"
81 	"vide: ret\n");
82 
83 static void init_amd_k5(struct cpuinfo_x86 *c)
84 {
85 #ifdef CONFIG_X86_32
86 /*
87  * General Systems BIOSen alias the cpu frequency registers
88  * of the Elan at 0x000df000. Unfortuantly, one of the Linux
89  * drivers subsequently pokes it, and changes the CPU speed.
90  * Workaround : Remove the unneeded alias.
91  */
92 #define CBAR		(0xfffc) /* Configuration Base Address  (32-bit) */
93 #define CBAR_ENB	(0x80000000)
94 #define CBAR_KEY	(0X000000CB)
95 	if (c->x86_model == 9 || c->x86_model == 10) {
96 		if (inl(CBAR) & CBAR_ENB)
97 			outl(0 | CBAR_KEY, CBAR);
98 	}
99 #endif
100 }
101 
102 static void init_amd_k6(struct cpuinfo_x86 *c)
103 {
104 #ifdef CONFIG_X86_32
105 	u32 l, h;
106 	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
107 
108 	if (c->x86_model < 6) {
109 		/* Based on AMD doc 20734R - June 2000 */
110 		if (c->x86_model == 0) {
111 			clear_cpu_cap(c, X86_FEATURE_APIC);
112 			set_cpu_cap(c, X86_FEATURE_PGE);
113 		}
114 		return;
115 	}
116 
117 	if (c->x86_model == 6 && c->x86_mask == 1) {
118 		const int K6_BUG_LOOP = 1000000;
119 		int n;
120 		void (*f_vide)(void);
121 		u64 d, d2;
122 
123 		printk(KERN_INFO "AMD K6 stepping B detected - ");
124 
125 		/*
126 		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
127 		 * calls at the same time.
128 		 */
129 
130 		n = K6_BUG_LOOP;
131 		f_vide = vide;
132 		d = rdtsc();
133 		while (n--)
134 			f_vide();
135 		d2 = rdtsc();
136 		d = d2-d;
137 
138 		if (d > 20*K6_BUG_LOOP)
139 			printk(KERN_CONT
140 				"system stability may be impaired when more than 32 MB are used.\n");
141 		else
142 			printk(KERN_CONT "probably OK (after B9730xxxx).\n");
143 	}
144 
145 	/* K6 with old style WHCR */
146 	if (c->x86_model < 8 ||
147 	   (c->x86_model == 8 && c->x86_mask < 8)) {
148 		/* We can only write allocate on the low 508Mb */
149 		if (mbytes > 508)
150 			mbytes = 508;
151 
152 		rdmsr(MSR_K6_WHCR, l, h);
153 		if ((l&0x0000FFFF) == 0) {
154 			unsigned long flags;
155 			l = (1<<0)|((mbytes/4)<<1);
156 			local_irq_save(flags);
157 			wbinvd();
158 			wrmsr(MSR_K6_WHCR, l, h);
159 			local_irq_restore(flags);
160 			printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
161 				mbytes);
162 		}
163 		return;
164 	}
165 
166 	if ((c->x86_model == 8 && c->x86_mask > 7) ||
167 	     c->x86_model == 9 || c->x86_model == 13) {
168 		/* The more serious chips .. */
169 
170 		if (mbytes > 4092)
171 			mbytes = 4092;
172 
173 		rdmsr(MSR_K6_WHCR, l, h);
174 		if ((l&0xFFFF0000) == 0) {
175 			unsigned long flags;
176 			l = ((mbytes>>2)<<22)|(1<<16);
177 			local_irq_save(flags);
178 			wbinvd();
179 			wrmsr(MSR_K6_WHCR, l, h);
180 			local_irq_restore(flags);
181 			printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
182 				mbytes);
183 		}
184 
185 		return;
186 	}
187 
188 	if (c->x86_model == 10) {
189 		/* AMD Geode LX is model 10 */
190 		/* placeholder for any needed mods */
191 		return;
192 	}
193 #endif
194 }
195 
196 static void init_amd_k7(struct cpuinfo_x86 *c)
197 {
198 #ifdef CONFIG_X86_32
199 	u32 l, h;
200 
201 	/*
202 	 * Bit 15 of Athlon specific MSR 15, needs to be 0
203 	 * to enable SSE on Palomino/Morgan/Barton CPU's.
204 	 * If the BIOS didn't enable it already, enable it here.
205 	 */
206 	if (c->x86_model >= 6 && c->x86_model <= 10) {
207 		if (!cpu_has(c, X86_FEATURE_XMM)) {
208 			printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
209 			msr_clear_bit(MSR_K7_HWCR, 15);
210 			set_cpu_cap(c, X86_FEATURE_XMM);
211 		}
212 	}
213 
214 	/*
215 	 * It's been determined by AMD that Athlons since model 8 stepping 1
216 	 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
217 	 * As per AMD technical note 27212 0.2
218 	 */
219 	if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
220 		rdmsr(MSR_K7_CLK_CTL, l, h);
221 		if ((l & 0xfff00000) != 0x20000000) {
222 			printk(KERN_INFO
223 			    "CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
224 					l, ((l & 0x000fffff)|0x20000000));
225 			wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
226 		}
227 	}
228 
229 	set_cpu_cap(c, X86_FEATURE_K7);
230 
231 	/* calling is from identify_secondary_cpu() ? */
232 	if (!c->cpu_index)
233 		return;
234 
235 	/*
236 	 * Certain Athlons might work (for various values of 'work') in SMP
237 	 * but they are not certified as MP capable.
238 	 */
239 	/* Athlon 660/661 is valid. */
240 	if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
241 	    (c->x86_mask == 1)))
242 		return;
243 
244 	/* Duron 670 is valid */
245 	if ((c->x86_model == 7) && (c->x86_mask == 0))
246 		return;
247 
248 	/*
249 	 * Athlon 662, Duron 671, and Athlon >model 7 have capability
250 	 * bit. It's worth noting that the A5 stepping (662) of some
251 	 * Athlon XP's have the MP bit set.
252 	 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
253 	 * more.
254 	 */
255 	if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
256 	    ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
257 	     (c->x86_model > 7))
258 		if (cpu_has(c, X86_FEATURE_MP))
259 			return;
260 
261 	/* If we get here, not a certified SMP capable AMD system. */
262 
263 	/*
264 	 * Don't taint if we are running SMP kernel on a single non-MP
265 	 * approved Athlon
266 	 */
267 	WARN_ONCE(1, "WARNING: This combination of AMD"
268 		" processors is not suitable for SMP.\n");
269 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
270 #endif
271 }
272 
273 #ifdef CONFIG_NUMA
274 /*
275  * To workaround broken NUMA config.  Read the comment in
276  * srat_detect_node().
277  */
278 static int nearby_node(int apicid)
279 {
280 	int i, node;
281 
282 	for (i = apicid - 1; i >= 0; i--) {
283 		node = __apicid_to_node[i];
284 		if (node != NUMA_NO_NODE && node_online(node))
285 			return node;
286 	}
287 	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
288 		node = __apicid_to_node[i];
289 		if (node != NUMA_NO_NODE && node_online(node))
290 			return node;
291 	}
292 	return first_node(node_online_map); /* Shouldn't happen */
293 }
294 #endif
295 
296 /*
297  * Fixup core topology information for
298  * (1) AMD multi-node processors
299  *     Assumption: Number of cores in each internal node is the same.
300  * (2) AMD processors supporting compute units
301  */
302 #ifdef CONFIG_SMP
303 static void amd_get_topology(struct cpuinfo_x86 *c)
304 {
305 	u32 cores_per_cu = 1;
306 	u8 node_id;
307 	int cpu = smp_processor_id();
308 
309 	/* get information required for multi-node processors */
310 	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
311 		u32 eax, ebx, ecx, edx;
312 
313 		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
314 		nodes_per_socket = ((ecx >> 8) & 7) + 1;
315 		node_id = ecx & 7;
316 
317 		/* get compute unit information */
318 		smp_num_siblings = ((ebx >> 8) & 3) + 1;
319 		c->compute_unit_id = ebx & 0xff;
320 		cores_per_cu += ((ebx >> 8) & 3);
321 	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
322 		u64 value;
323 
324 		rdmsrl(MSR_FAM10H_NODE_ID, value);
325 		nodes_per_socket = ((value >> 3) & 7) + 1;
326 		node_id = value & 7;
327 	} else
328 		return;
329 
330 	/* fixup multi-node processor information */
331 	if (nodes_per_socket > 1) {
332 		u32 cores_per_node;
333 		u32 cus_per_node;
334 
335 		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
336 		cores_per_node = c->x86_max_cores / nodes_per_socket;
337 		cus_per_node = cores_per_node / cores_per_cu;
338 
339 		/* store NodeID, use llc_shared_map to store sibling info */
340 		per_cpu(cpu_llc_id, cpu) = node_id;
341 
342 		/* core id has to be in the [0 .. cores_per_node - 1] range */
343 		c->cpu_core_id %= cores_per_node;
344 		c->compute_unit_id %= cus_per_node;
345 	}
346 }
347 #endif
348 
349 /*
350  * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
351  * Assumes number of cores is a power of two.
352  */
353 static void amd_detect_cmp(struct cpuinfo_x86 *c)
354 {
355 #ifdef CONFIG_SMP
356 	unsigned bits;
357 	int cpu = smp_processor_id();
358 	unsigned int socket_id, core_complex_id;
359 
360 	bits = c->x86_coreid_bits;
361 	/* Low order bits define the core id (index of core in socket) */
362 	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
363 	/* Convert the initial APIC ID into the socket ID */
364 	c->phys_proc_id = c->initial_apicid >> bits;
365 	/* use socket ID also for last level cache */
366 	per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
367 	amd_get_topology(c);
368 
369 	/*
370 	 * Fix percpu cpu_llc_id here as LLC topology is different
371 	 * for Fam17h systems.
372 	 */
373 	 if (c->x86 != 0x17 || !cpuid_edx(0x80000006))
374 		return;
375 
376 	socket_id	= (c->apicid >> bits) - 1;
377 	core_complex_id	= (c->apicid & ((1 << bits) - 1)) >> 3;
378 
379 	per_cpu(cpu_llc_id, cpu) = (socket_id << 3) | core_complex_id;
380 #endif
381 }
382 
383 u16 amd_get_nb_id(int cpu)
384 {
385 	u16 id = 0;
386 #ifdef CONFIG_SMP
387 	id = per_cpu(cpu_llc_id, cpu);
388 #endif
389 	return id;
390 }
391 EXPORT_SYMBOL_GPL(amd_get_nb_id);
392 
393 u32 amd_get_nodes_per_socket(void)
394 {
395 	return nodes_per_socket;
396 }
397 EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
398 
399 static void srat_detect_node(struct cpuinfo_x86 *c)
400 {
401 #ifdef CONFIG_NUMA
402 	int cpu = smp_processor_id();
403 	int node;
404 	unsigned apicid = c->apicid;
405 
406 	node = numa_cpu_node(cpu);
407 	if (node == NUMA_NO_NODE)
408 		node = per_cpu(cpu_llc_id, cpu);
409 
410 	/*
411 	 * On multi-fabric platform (e.g. Numascale NumaChip) a
412 	 * platform-specific handler needs to be called to fixup some
413 	 * IDs of the CPU.
414 	 */
415 	if (x86_cpuinit.fixup_cpu_id)
416 		x86_cpuinit.fixup_cpu_id(c, node);
417 
418 	if (!node_online(node)) {
419 		/*
420 		 * Two possibilities here:
421 		 *
422 		 * - The CPU is missing memory and no node was created.  In
423 		 *   that case try picking one from a nearby CPU.
424 		 *
425 		 * - The APIC IDs differ from the HyperTransport node IDs
426 		 *   which the K8 northbridge parsing fills in.  Assume
427 		 *   they are all increased by a constant offset, but in
428 		 *   the same order as the HT nodeids.  If that doesn't
429 		 *   result in a usable node fall back to the path for the
430 		 *   previous case.
431 		 *
432 		 * This workaround operates directly on the mapping between
433 		 * APIC ID and NUMA node, assuming certain relationship
434 		 * between APIC ID, HT node ID and NUMA topology.  As going
435 		 * through CPU mapping may alter the outcome, directly
436 		 * access __apicid_to_node[].
437 		 */
438 		int ht_nodeid = c->initial_apicid;
439 
440 		if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
441 			node = __apicid_to_node[ht_nodeid];
442 		/* Pick a nearby node */
443 		if (!node_online(node))
444 			node = nearby_node(apicid);
445 	}
446 	numa_set_node(cpu, node);
447 #endif
448 }
449 
450 static void early_init_amd_mc(struct cpuinfo_x86 *c)
451 {
452 #ifdef CONFIG_SMP
453 	unsigned bits, ecx;
454 
455 	/* Multi core CPU? */
456 	if (c->extended_cpuid_level < 0x80000008)
457 		return;
458 
459 	ecx = cpuid_ecx(0x80000008);
460 
461 	c->x86_max_cores = (ecx & 0xff) + 1;
462 
463 	/* CPU telling us the core id bits shift? */
464 	bits = (ecx >> 12) & 0xF;
465 
466 	/* Otherwise recompute */
467 	if (bits == 0) {
468 		while ((1 << bits) < c->x86_max_cores)
469 			bits++;
470 	}
471 
472 	c->x86_coreid_bits = bits;
473 #endif
474 }
475 
476 static void bsp_init_amd(struct cpuinfo_x86 *c)
477 {
478 
479 #ifdef CONFIG_X86_64
480 	if (c->x86 >= 0xf) {
481 		unsigned long long tseg;
482 
483 		/*
484 		 * Split up direct mapping around the TSEG SMM area.
485 		 * Don't do it for gbpages because there seems very little
486 		 * benefit in doing so.
487 		 */
488 		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
489 			unsigned long pfn = tseg >> PAGE_SHIFT;
490 
491 			printk(KERN_DEBUG "tseg: %010llx\n", tseg);
492 			if (pfn_range_is_mapped(pfn, pfn + 1))
493 				set_memory_4k((unsigned long)__va(tseg), 1);
494 		}
495 	}
496 #endif
497 
498 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
499 
500 		if (c->x86 > 0x10 ||
501 		    (c->x86 == 0x10 && c->x86_model >= 0x2)) {
502 			u64 val;
503 
504 			rdmsrl(MSR_K7_HWCR, val);
505 			if (!(val & BIT(24)))
506 				printk(KERN_WARNING FW_BUG "TSC doesn't count "
507 					"with P0 frequency!\n");
508 		}
509 	}
510 
511 	if (c->x86 == 0x15) {
512 		unsigned long upperbit;
513 		u32 cpuid, assoc;
514 
515 		cpuid	 = cpuid_edx(0x80000005);
516 		assoc	 = cpuid >> 16 & 0xff;
517 		upperbit = ((cpuid >> 24) << 10) / assoc;
518 
519 		va_align.mask	  = (upperbit - 1) & PAGE_MASK;
520 		va_align.flags    = ALIGN_VA_32 | ALIGN_VA_64;
521 
522 		/* A random value per boot for bit slice [12:upper_bit) */
523 		va_align.bits = get_random_int() & va_align.mask;
524 	}
525 
526 	if (cpu_has(c, X86_FEATURE_MWAITX))
527 		use_mwaitx_delay();
528 }
529 
530 static void early_init_amd(struct cpuinfo_x86 *c)
531 {
532 	early_init_amd_mc(c);
533 
534 	/*
535 	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
536 	 * with P/T states and does not stop in deep C-states
537 	 */
538 	if (c->x86_power & (1 << 8)) {
539 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
540 		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
541 		if (!check_tsc_unstable())
542 			set_sched_clock_stable();
543 	}
544 
545 #ifdef CONFIG_X86_64
546 	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
547 #else
548 	/*  Set MTRR capability flag if appropriate */
549 	if (c->x86 == 5)
550 		if (c->x86_model == 13 || c->x86_model == 9 ||
551 		    (c->x86_model == 8 && c->x86_mask >= 8))
552 			set_cpu_cap(c, X86_FEATURE_K6_MTRR);
553 #endif
554 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
555 	/*
556 	 * ApicID can always be treated as an 8-bit value for AMD APIC versions
557 	 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
558 	 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
559 	 * after 16h.
560 	 */
561 	if (cpu_has_apic && c->x86 > 0x16) {
562 		set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
563 	} else if (cpu_has_apic && c->x86 >= 0xf) {
564 		/* check CPU config space for extended APIC ID */
565 		unsigned int val;
566 		val = read_pci_config(0, 24, 0, 0x68);
567 		if ((val & ((1 << 17) | (1 << 18))) == ((1 << 17) | (1 << 18)))
568 			set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
569 	}
570 #endif
571 
572 	/*
573 	 * This is only needed to tell the kernel whether to use VMCALL
574 	 * and VMMCALL.  VMMCALL is never executed except under virt, so
575 	 * we can set it unconditionally.
576 	 */
577 	set_cpu_cap(c, X86_FEATURE_VMMCALL);
578 
579 	/* F16h erratum 793, CVE-2013-6885 */
580 	if (c->x86 == 0x16 && c->x86_model <= 0xf)
581 		msr_set_bit(MSR_AMD64_LS_CFG, 15);
582 }
583 
584 static const int amd_erratum_383[];
585 static const int amd_erratum_400[];
586 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
587 
588 static void init_amd_k8(struct cpuinfo_x86 *c)
589 {
590 	u32 level;
591 	u64 value;
592 
593 	/* On C+ stepping K8 rep microcode works well for copy/memset */
594 	level = cpuid_eax(1);
595 	if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
596 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
597 
598 	/*
599 	 * Some BIOSes incorrectly force this feature, but only K8 revision D
600 	 * (model = 0x14) and later actually support it.
601 	 * (AMD Erratum #110, docId: 25759).
602 	 */
603 	if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
604 		clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
605 		if (!rdmsrl_amd_safe(0xc001100d, &value)) {
606 			value &= ~BIT_64(32);
607 			wrmsrl_amd_safe(0xc001100d, value);
608 		}
609 	}
610 
611 	if (!c->x86_model_id[0])
612 		strcpy(c->x86_model_id, "Hammer");
613 
614 #ifdef CONFIG_SMP
615 	/*
616 	 * Disable TLB flush filter by setting HWCR.FFDIS on K8
617 	 * bit 6 of msr C001_0015
618 	 *
619 	 * Errata 63 for SH-B3 steppings
620 	 * Errata 122 for all steppings (F+ have it disabled by default)
621 	 */
622 	msr_set_bit(MSR_K7_HWCR, 6);
623 #endif
624 }
625 
626 static void init_amd_gh(struct cpuinfo_x86 *c)
627 {
628 #ifdef CONFIG_X86_64
629 	/* do this for boot cpu */
630 	if (c == &boot_cpu_data)
631 		check_enable_amd_mmconf_dmi();
632 
633 	fam10h_check_enable_mmcfg();
634 #endif
635 
636 	/*
637 	 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
638 	 * is always needed when GART is enabled, even in a kernel which has no
639 	 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
640 	 * If it doesn't, we do it here as suggested by the BKDG.
641 	 *
642 	 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
643 	 */
644 	msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
645 
646 	/*
647 	 * On family 10h BIOS may not have properly enabled WC+ support, causing
648 	 * it to be converted to CD memtype. This may result in performance
649 	 * degradation for certain nested-paging guests. Prevent this conversion
650 	 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
651 	 *
652 	 * NOTE: we want to use the _safe accessors so as not to #GP kvm
653 	 * guests on older kvm hosts.
654 	 */
655 	msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
656 
657 	if (cpu_has_amd_erratum(c, amd_erratum_383))
658 		set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
659 }
660 
661 static void init_amd_bd(struct cpuinfo_x86 *c)
662 {
663 	u64 value;
664 
665 	/* re-enable TopologyExtensions if switched off by BIOS */
666 	if ((c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
667 	    !cpu_has(c, X86_FEATURE_TOPOEXT)) {
668 
669 		if (msr_set_bit(0xc0011005, 54) > 0) {
670 			rdmsrl(0xc0011005, value);
671 			if (value & BIT_64(54)) {
672 				set_cpu_cap(c, X86_FEATURE_TOPOEXT);
673 				pr_info(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
674 			}
675 		}
676 	}
677 
678 	/*
679 	 * The way access filter has a performance penalty on some workloads.
680 	 * Disable it on the affected CPUs.
681 	 */
682 	if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
683 		if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
684 			value |= 0x1E;
685 			wrmsrl_safe(MSR_F15H_IC_CFG, value);
686 		}
687 	}
688 }
689 
690 static void init_amd(struct cpuinfo_x86 *c)
691 {
692 	u32 dummy;
693 
694 	early_init_amd(c);
695 
696 	/*
697 	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
698 	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
699 	 */
700 	clear_cpu_cap(c, 0*32+31);
701 
702 	if (c->x86 >= 0x10)
703 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
704 
705 	/* get apicid instead of initial apic id from cpuid */
706 	c->apicid = hard_smp_processor_id();
707 
708 	/* K6s reports MCEs but don't actually have all the MSRs */
709 	if (c->x86 < 6)
710 		clear_cpu_cap(c, X86_FEATURE_MCE);
711 
712 	switch (c->x86) {
713 	case 4:    init_amd_k5(c); break;
714 	case 5:    init_amd_k6(c); break;
715 	case 6:	   init_amd_k7(c); break;
716 	case 0xf:  init_amd_k8(c); break;
717 	case 0x10: init_amd_gh(c); break;
718 	case 0x15: init_amd_bd(c); break;
719 	}
720 
721 	/* Enable workaround for FXSAVE leak */
722 	if (c->x86 >= 6)
723 		set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
724 
725 	cpu_detect_cache_sizes(c);
726 
727 	/* Multi core CPU? */
728 	if (c->extended_cpuid_level >= 0x80000008) {
729 		amd_detect_cmp(c);
730 		srat_detect_node(c);
731 	}
732 
733 #ifdef CONFIG_X86_32
734 	detect_ht(c);
735 #endif
736 
737 	init_amd_cacheinfo(c);
738 
739 	if (c->x86 >= 0xf)
740 		set_cpu_cap(c, X86_FEATURE_K8);
741 
742 	if (cpu_has_xmm2) {
743 		/* MFENCE stops RDTSC speculation */
744 		set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
745 	}
746 
747 	/*
748 	 * Family 0x12 and above processors have APIC timer
749 	 * running in deep C states.
750 	 */
751 	if (c->x86 > 0x11)
752 		set_cpu_cap(c, X86_FEATURE_ARAT);
753 
754 	if (cpu_has_amd_erratum(c, amd_erratum_400))
755 		set_cpu_bug(c, X86_BUG_AMD_APIC_C1E);
756 
757 	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
758 
759 	/* 3DNow or LM implies PREFETCHW */
760 	if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
761 		if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
762 			set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
763 
764 	/* AMD CPUs don't reset SS attributes on SYSRET */
765 	set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
766 }
767 
768 #ifdef CONFIG_X86_32
769 static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
770 {
771 	/* AMD errata T13 (order #21922) */
772 	if ((c->x86 == 6)) {
773 		/* Duron Rev A0 */
774 		if (c->x86_model == 3 && c->x86_mask == 0)
775 			size = 64;
776 		/* Tbird rev A1/A2 */
777 		if (c->x86_model == 4 &&
778 			(c->x86_mask == 0 || c->x86_mask == 1))
779 			size = 256;
780 	}
781 	return size;
782 }
783 #endif
784 
785 static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
786 {
787 	u32 ebx, eax, ecx, edx;
788 	u16 mask = 0xfff;
789 
790 	if (c->x86 < 0xf)
791 		return;
792 
793 	if (c->extended_cpuid_level < 0x80000006)
794 		return;
795 
796 	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
797 
798 	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
799 	tlb_lli_4k[ENTRIES] = ebx & mask;
800 
801 	/*
802 	 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
803 	 * characteristics from the CPUID function 0x80000005 instead.
804 	 */
805 	if (c->x86 == 0xf) {
806 		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
807 		mask = 0xff;
808 	}
809 
810 	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
811 	if (!((eax >> 16) & mask))
812 		tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
813 	else
814 		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
815 
816 	/* a 4M entry uses two 2M entries */
817 	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
818 
819 	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
820 	if (!(eax & mask)) {
821 		/* Erratum 658 */
822 		if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
823 			tlb_lli_2m[ENTRIES] = 1024;
824 		} else {
825 			cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
826 			tlb_lli_2m[ENTRIES] = eax & 0xff;
827 		}
828 	} else
829 		tlb_lli_2m[ENTRIES] = eax & mask;
830 
831 	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
832 }
833 
834 static const struct cpu_dev amd_cpu_dev = {
835 	.c_vendor	= "AMD",
836 	.c_ident	= { "AuthenticAMD" },
837 #ifdef CONFIG_X86_32
838 	.legacy_models = {
839 		{ .family = 4, .model_names =
840 		  {
841 			  [3] = "486 DX/2",
842 			  [7] = "486 DX/2-WB",
843 			  [8] = "486 DX/4",
844 			  [9] = "486 DX/4-WB",
845 			  [14] = "Am5x86-WT",
846 			  [15] = "Am5x86-WB"
847 		  }
848 		},
849 	},
850 	.legacy_cache_size = amd_size_cache,
851 #endif
852 	.c_early_init   = early_init_amd,
853 	.c_detect_tlb	= cpu_detect_tlb_amd,
854 	.c_bsp_init	= bsp_init_amd,
855 	.c_init		= init_amd,
856 	.c_x86_vendor	= X86_VENDOR_AMD,
857 };
858 
859 cpu_dev_register(amd_cpu_dev);
860 
861 /*
862  * AMD errata checking
863  *
864  * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
865  * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
866  * have an OSVW id assigned, which it takes as first argument. Both take a
867  * variable number of family-specific model-stepping ranges created by
868  * AMD_MODEL_RANGE().
869  *
870  * Example:
871  *
872  * const int amd_erratum_319[] =
873  *	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
874  *			   AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
875  *			   AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
876  */
877 
878 #define AMD_LEGACY_ERRATUM(...)		{ -1, __VA_ARGS__, 0 }
879 #define AMD_OSVW_ERRATUM(osvw_id, ...)	{ osvw_id, __VA_ARGS__, 0 }
880 #define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
881 	((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
882 #define AMD_MODEL_RANGE_FAMILY(range)	(((range) >> 24) & 0xff)
883 #define AMD_MODEL_RANGE_START(range)	(((range) >> 12) & 0xfff)
884 #define AMD_MODEL_RANGE_END(range)	((range) & 0xfff)
885 
886 static const int amd_erratum_400[] =
887 	AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
888 			    AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
889 
890 static const int amd_erratum_383[] =
891 	AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
892 
893 
894 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
895 {
896 	int osvw_id = *erratum++;
897 	u32 range;
898 	u32 ms;
899 
900 	if (osvw_id >= 0 && osvw_id < 65536 &&
901 	    cpu_has(cpu, X86_FEATURE_OSVW)) {
902 		u64 osvw_len;
903 
904 		rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
905 		if (osvw_id < osvw_len) {
906 			u64 osvw_bits;
907 
908 			rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
909 			    osvw_bits);
910 			return osvw_bits & (1ULL << (osvw_id & 0x3f));
911 		}
912 	}
913 
914 	/* OSVW unavailable or ID unknown, match family-model-stepping range */
915 	ms = (cpu->x86_model << 4) | cpu->x86_mask;
916 	while ((range = *erratum++))
917 		if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
918 		    (ms >= AMD_MODEL_RANGE_START(range)) &&
919 		    (ms <= AMD_MODEL_RANGE_END(range)))
920 			return true;
921 
922 	return false;
923 }
924 
925 void set_dr_addr_mask(unsigned long mask, int dr)
926 {
927 	if (!boot_cpu_has(X86_FEATURE_BPEXT))
928 		return;
929 
930 	switch (dr) {
931 	case 0:
932 		wrmsr(MSR_F16H_DR0_ADDR_MASK, mask, 0);
933 		break;
934 	case 1:
935 	case 2:
936 	case 3:
937 		wrmsr(MSR_F16H_DR1_ADDR_MASK - 1 + dr, mask, 0);
938 		break;
939 	default:
940 		break;
941 	}
942 }
943