xref: /linux/arch/x86/kernel/cpu/amd.c (revision 607bfbd7ffc60156ae0831c917497dc91a57dd8d)
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\t.align 4\nvide: ret");
79 
80 static void init_amd_k5(struct cpuinfo_x86 *c)
81 {
82 #ifdef CONFIG_X86_32
83 /*
84  * General Systems BIOSen alias the cpu frequency registers
85  * of the Elan at 0x000df000. Unfortuantly, one of the Linux
86  * drivers subsequently pokes it, and changes the CPU speed.
87  * Workaround : Remove the unneeded alias.
88  */
89 #define CBAR		(0xfffc) /* Configuration Base Address  (32-bit) */
90 #define CBAR_ENB	(0x80000000)
91 #define CBAR_KEY	(0X000000CB)
92 	if (c->x86_model == 9 || c->x86_model == 10) {
93 		if (inl(CBAR) & CBAR_ENB)
94 			outl(0 | CBAR_KEY, CBAR);
95 	}
96 #endif
97 }
98 
99 static void init_amd_k6(struct cpuinfo_x86 *c)
100 {
101 #ifdef CONFIG_X86_32
102 	u32 l, h;
103 	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
104 
105 	if (c->x86_model < 6) {
106 		/* Based on AMD doc 20734R - June 2000 */
107 		if (c->x86_model == 0) {
108 			clear_cpu_cap(c, X86_FEATURE_APIC);
109 			set_cpu_cap(c, X86_FEATURE_PGE);
110 		}
111 		return;
112 	}
113 
114 	if (c->x86_model == 6 && c->x86_mask == 1) {
115 		const int K6_BUG_LOOP = 1000000;
116 		int n;
117 		void (*f_vide)(void);
118 		u64 d, d2;
119 
120 		pr_info("AMD K6 stepping B detected - ");
121 
122 		/*
123 		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
124 		 * calls at the same time.
125 		 */
126 
127 		n = K6_BUG_LOOP;
128 		f_vide = vide;
129 		d = rdtsc();
130 		while (n--)
131 			f_vide();
132 		d2 = rdtsc();
133 		d = d2-d;
134 
135 		if (d > 20*K6_BUG_LOOP)
136 			pr_cont("system stability may be impaired when more than 32 MB are used.\n");
137 		else
138 			pr_cont("probably OK (after B9730xxxx).\n");
139 	}
140 
141 	/* K6 with old style WHCR */
142 	if (c->x86_model < 8 ||
143 	   (c->x86_model == 8 && c->x86_mask < 8)) {
144 		/* We can only write allocate on the low 508Mb */
145 		if (mbytes > 508)
146 			mbytes = 508;
147 
148 		rdmsr(MSR_K6_WHCR, l, h);
149 		if ((l&0x0000FFFF) == 0) {
150 			unsigned long flags;
151 			l = (1<<0)|((mbytes/4)<<1);
152 			local_irq_save(flags);
153 			wbinvd();
154 			wrmsr(MSR_K6_WHCR, l, h);
155 			local_irq_restore(flags);
156 			pr_info("Enabling old style K6 write allocation for %d Mb\n",
157 				mbytes);
158 		}
159 		return;
160 	}
161 
162 	if ((c->x86_model == 8 && c->x86_mask > 7) ||
163 	     c->x86_model == 9 || c->x86_model == 13) {
164 		/* The more serious chips .. */
165 
166 		if (mbytes > 4092)
167 			mbytes = 4092;
168 
169 		rdmsr(MSR_K6_WHCR, l, h);
170 		if ((l&0xFFFF0000) == 0) {
171 			unsigned long flags;
172 			l = ((mbytes>>2)<<22)|(1<<16);
173 			local_irq_save(flags);
174 			wbinvd();
175 			wrmsr(MSR_K6_WHCR, l, h);
176 			local_irq_restore(flags);
177 			pr_info("Enabling new style K6 write allocation for %d Mb\n",
178 				mbytes);
179 		}
180 
181 		return;
182 	}
183 
184 	if (c->x86_model == 10) {
185 		/* AMD Geode LX is model 10 */
186 		/* placeholder for any needed mods */
187 		return;
188 	}
189 #endif
190 }
191 
192 static void init_amd_k7(struct cpuinfo_x86 *c)
193 {
194 #ifdef CONFIG_X86_32
195 	u32 l, h;
196 
197 	/*
198 	 * Bit 15 of Athlon specific MSR 15, needs to be 0
199 	 * to enable SSE on Palomino/Morgan/Barton CPU's.
200 	 * If the BIOS didn't enable it already, enable it here.
201 	 */
202 	if (c->x86_model >= 6 && c->x86_model <= 10) {
203 		if (!cpu_has(c, X86_FEATURE_XMM)) {
204 			pr_info("Enabling disabled K7/SSE Support.\n");
205 			msr_clear_bit(MSR_K7_HWCR, 15);
206 			set_cpu_cap(c, X86_FEATURE_XMM);
207 		}
208 	}
209 
210 	/*
211 	 * It's been determined by AMD that Athlons since model 8 stepping 1
212 	 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
213 	 * As per AMD technical note 27212 0.2
214 	 */
215 	if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
216 		rdmsr(MSR_K7_CLK_CTL, l, h);
217 		if ((l & 0xfff00000) != 0x20000000) {
218 			pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
219 				l, ((l & 0x000fffff)|0x20000000));
220 			wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
221 		}
222 	}
223 
224 	set_cpu_cap(c, X86_FEATURE_K7);
225 
226 	/* calling is from identify_secondary_cpu() ? */
227 	if (!c->cpu_index)
228 		return;
229 
230 	/*
231 	 * Certain Athlons might work (for various values of 'work') in SMP
232 	 * but they are not certified as MP capable.
233 	 */
234 	/* Athlon 660/661 is valid. */
235 	if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
236 	    (c->x86_mask == 1)))
237 		return;
238 
239 	/* Duron 670 is valid */
240 	if ((c->x86_model == 7) && (c->x86_mask == 0))
241 		return;
242 
243 	/*
244 	 * Athlon 662, Duron 671, and Athlon >model 7 have capability
245 	 * bit. It's worth noting that the A5 stepping (662) of some
246 	 * Athlon XP's have the MP bit set.
247 	 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
248 	 * more.
249 	 */
250 	if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
251 	    ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
252 	     (c->x86_model > 7))
253 		if (cpu_has(c, X86_FEATURE_MP))
254 			return;
255 
256 	/* If we get here, not a certified SMP capable AMD system. */
257 
258 	/*
259 	 * Don't taint if we are running SMP kernel on a single non-MP
260 	 * approved Athlon
261 	 */
262 	WARN_ONCE(1, "WARNING: This combination of AMD"
263 		" processors is not suitable for SMP.\n");
264 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
265 #endif
266 }
267 
268 #ifdef CONFIG_NUMA
269 /*
270  * To workaround broken NUMA config.  Read the comment in
271  * srat_detect_node().
272  */
273 static int nearby_node(int apicid)
274 {
275 	int i, node;
276 
277 	for (i = apicid - 1; i >= 0; i--) {
278 		node = __apicid_to_node[i];
279 		if (node != NUMA_NO_NODE && node_online(node))
280 			return node;
281 	}
282 	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
283 		node = __apicid_to_node[i];
284 		if (node != NUMA_NO_NODE && node_online(node))
285 			return node;
286 	}
287 	return first_node(node_online_map); /* Shouldn't happen */
288 }
289 #endif
290 
291 /*
292  * Fixup core topology information for
293  * (1) AMD multi-node processors
294  *     Assumption: Number of cores in each internal node is the same.
295  * (2) AMD processors supporting compute units
296  */
297 #ifdef CONFIG_SMP
298 static void amd_get_topology(struct cpuinfo_x86 *c)
299 {
300 	u32 cores_per_cu = 1;
301 	u8 node_id;
302 	int cpu = smp_processor_id();
303 
304 	/* get information required for multi-node processors */
305 	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
306 		u32 eax, ebx, ecx, edx;
307 
308 		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
309 		nodes_per_socket = ((ecx >> 8) & 7) + 1;
310 		node_id = ecx & 7;
311 
312 		/* get compute unit information */
313 		smp_num_siblings = ((ebx >> 8) & 3) + 1;
314 		c->compute_unit_id = ebx & 0xff;
315 		cores_per_cu += ((ebx >> 8) & 3);
316 	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
317 		u64 value;
318 
319 		rdmsrl(MSR_FAM10H_NODE_ID, value);
320 		nodes_per_socket = ((value >> 3) & 7) + 1;
321 		node_id = value & 7;
322 	} else
323 		return;
324 
325 	/* fixup multi-node processor information */
326 	if (nodes_per_socket > 1) {
327 		u32 cores_per_node;
328 		u32 cus_per_node;
329 
330 		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
331 		cores_per_node = c->x86_max_cores / nodes_per_socket;
332 		cus_per_node = cores_per_node / cores_per_cu;
333 
334 		/* store NodeID, use llc_shared_map to store sibling info */
335 		per_cpu(cpu_llc_id, cpu) = node_id;
336 
337 		/* core id has to be in the [0 .. cores_per_node - 1] range */
338 		c->cpu_core_id %= cores_per_node;
339 		c->compute_unit_id %= cus_per_node;
340 	}
341 }
342 #endif
343 
344 /*
345  * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
346  * Assumes number of cores is a power of two.
347  */
348 static void amd_detect_cmp(struct cpuinfo_x86 *c)
349 {
350 #ifdef CONFIG_SMP
351 	unsigned bits;
352 	int cpu = smp_processor_id();
353 	unsigned int socket_id, core_complex_id;
354 
355 	bits = c->x86_coreid_bits;
356 	/* Low order bits define the core id (index of core in socket) */
357 	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
358 	/* Convert the initial APIC ID into the socket ID */
359 	c->phys_proc_id = c->initial_apicid >> bits;
360 	/* use socket ID also for last level cache */
361 	per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
362 	amd_get_topology(c);
363 
364 	/*
365 	 * Fix percpu cpu_llc_id here as LLC topology is different
366 	 * for Fam17h systems.
367 	 */
368 	 if (c->x86 != 0x17 || !cpuid_edx(0x80000006))
369 		return;
370 
371 	socket_id	= (c->apicid >> bits) - 1;
372 	core_complex_id	= (c->apicid & ((1 << bits) - 1)) >> 3;
373 
374 	per_cpu(cpu_llc_id, cpu) = (socket_id << 3) | core_complex_id;
375 #endif
376 }
377 
378 u16 amd_get_nb_id(int cpu)
379 {
380 	u16 id = 0;
381 #ifdef CONFIG_SMP
382 	id = per_cpu(cpu_llc_id, cpu);
383 #endif
384 	return id;
385 }
386 EXPORT_SYMBOL_GPL(amd_get_nb_id);
387 
388 u32 amd_get_nodes_per_socket(void)
389 {
390 	return nodes_per_socket;
391 }
392 EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
393 
394 static void srat_detect_node(struct cpuinfo_x86 *c)
395 {
396 #ifdef CONFIG_NUMA
397 	int cpu = smp_processor_id();
398 	int node;
399 	unsigned apicid = c->apicid;
400 
401 	node = numa_cpu_node(cpu);
402 	if (node == NUMA_NO_NODE)
403 		node = per_cpu(cpu_llc_id, cpu);
404 
405 	/*
406 	 * On multi-fabric platform (e.g. Numascale NumaChip) a
407 	 * platform-specific handler needs to be called to fixup some
408 	 * IDs of the CPU.
409 	 */
410 	if (x86_cpuinit.fixup_cpu_id)
411 		x86_cpuinit.fixup_cpu_id(c, node);
412 
413 	if (!node_online(node)) {
414 		/*
415 		 * Two possibilities here:
416 		 *
417 		 * - The CPU is missing memory and no node was created.  In
418 		 *   that case try picking one from a nearby CPU.
419 		 *
420 		 * - The APIC IDs differ from the HyperTransport node IDs
421 		 *   which the K8 northbridge parsing fills in.  Assume
422 		 *   they are all increased by a constant offset, but in
423 		 *   the same order as the HT nodeids.  If that doesn't
424 		 *   result in a usable node fall back to the path for the
425 		 *   previous case.
426 		 *
427 		 * This workaround operates directly on the mapping between
428 		 * APIC ID and NUMA node, assuming certain relationship
429 		 * between APIC ID, HT node ID and NUMA topology.  As going
430 		 * through CPU mapping may alter the outcome, directly
431 		 * access __apicid_to_node[].
432 		 */
433 		int ht_nodeid = c->initial_apicid;
434 
435 		if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
436 			node = __apicid_to_node[ht_nodeid];
437 		/* Pick a nearby node */
438 		if (!node_online(node))
439 			node = nearby_node(apicid);
440 	}
441 	numa_set_node(cpu, node);
442 #endif
443 }
444 
445 static void early_init_amd_mc(struct cpuinfo_x86 *c)
446 {
447 #ifdef CONFIG_SMP
448 	unsigned bits, ecx;
449 
450 	/* Multi core CPU? */
451 	if (c->extended_cpuid_level < 0x80000008)
452 		return;
453 
454 	ecx = cpuid_ecx(0x80000008);
455 
456 	c->x86_max_cores = (ecx & 0xff) + 1;
457 
458 	/* CPU telling us the core id bits shift? */
459 	bits = (ecx >> 12) & 0xF;
460 
461 	/* Otherwise recompute */
462 	if (bits == 0) {
463 		while ((1 << bits) < c->x86_max_cores)
464 			bits++;
465 	}
466 
467 	c->x86_coreid_bits = bits;
468 #endif
469 }
470 
471 static void bsp_init_amd(struct cpuinfo_x86 *c)
472 {
473 
474 #ifdef CONFIG_X86_64
475 	if (c->x86 >= 0xf) {
476 		unsigned long long tseg;
477 
478 		/*
479 		 * Split up direct mapping around the TSEG SMM area.
480 		 * Don't do it for gbpages because there seems very little
481 		 * benefit in doing so.
482 		 */
483 		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
484 			unsigned long pfn = tseg >> PAGE_SHIFT;
485 
486 			pr_debug("tseg: %010llx\n", tseg);
487 			if (pfn_range_is_mapped(pfn, pfn + 1))
488 				set_memory_4k((unsigned long)__va(tseg), 1);
489 		}
490 	}
491 #endif
492 
493 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
494 
495 		if (c->x86 > 0x10 ||
496 		    (c->x86 == 0x10 && c->x86_model >= 0x2)) {
497 			u64 val;
498 
499 			rdmsrl(MSR_K7_HWCR, val);
500 			if (!(val & BIT(24)))
501 				pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
502 		}
503 	}
504 
505 	if (c->x86 == 0x15) {
506 		unsigned long upperbit;
507 		u32 cpuid, assoc;
508 
509 		cpuid	 = cpuid_edx(0x80000005);
510 		assoc	 = cpuid >> 16 & 0xff;
511 		upperbit = ((cpuid >> 24) << 10) / assoc;
512 
513 		va_align.mask	  = (upperbit - 1) & PAGE_MASK;
514 		va_align.flags    = ALIGN_VA_32 | ALIGN_VA_64;
515 
516 		/* A random value per boot for bit slice [12:upper_bit) */
517 		va_align.bits = get_random_int() & va_align.mask;
518 	}
519 
520 	if (cpu_has(c, X86_FEATURE_MWAITX))
521 		use_mwaitx_delay();
522 }
523 
524 static void early_init_amd(struct cpuinfo_x86 *c)
525 {
526 	early_init_amd_mc(c);
527 
528 	/*
529 	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
530 	 * with P/T states and does not stop in deep C-states
531 	 */
532 	if (c->x86_power & (1 << 8)) {
533 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
534 		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
535 		if (!check_tsc_unstable())
536 			set_sched_clock_stable();
537 	}
538 
539 #ifdef CONFIG_X86_64
540 	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
541 #else
542 	/*  Set MTRR capability flag if appropriate */
543 	if (c->x86 == 5)
544 		if (c->x86_model == 13 || c->x86_model == 9 ||
545 		    (c->x86_model == 8 && c->x86_mask >= 8))
546 			set_cpu_cap(c, X86_FEATURE_K6_MTRR);
547 #endif
548 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
549 	/*
550 	 * ApicID can always be treated as an 8-bit value for AMD APIC versions
551 	 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
552 	 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
553 	 * after 16h.
554 	 */
555 	if (cpu_has_apic && c->x86 > 0x16) {
556 		set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
557 	} else if (cpu_has_apic && c->x86 >= 0xf) {
558 		/* check CPU config space for extended APIC ID */
559 		unsigned int val;
560 		val = read_pci_config(0, 24, 0, 0x68);
561 		if ((val & ((1 << 17) | (1 << 18))) == ((1 << 17) | (1 << 18)))
562 			set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
563 	}
564 #endif
565 
566 	/*
567 	 * This is only needed to tell the kernel whether to use VMCALL
568 	 * and VMMCALL.  VMMCALL is never executed except under virt, so
569 	 * we can set it unconditionally.
570 	 */
571 	set_cpu_cap(c, X86_FEATURE_VMMCALL);
572 
573 	/* F16h erratum 793, CVE-2013-6885 */
574 	if (c->x86 == 0x16 && c->x86_model <= 0xf)
575 		msr_set_bit(MSR_AMD64_LS_CFG, 15);
576 }
577 
578 static const int amd_erratum_383[];
579 static const int amd_erratum_400[];
580 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum);
581 
582 static void init_amd_k8(struct cpuinfo_x86 *c)
583 {
584 	u32 level;
585 	u64 value;
586 
587 	/* On C+ stepping K8 rep microcode works well for copy/memset */
588 	level = cpuid_eax(1);
589 	if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
590 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
591 
592 	/*
593 	 * Some BIOSes incorrectly force this feature, but only K8 revision D
594 	 * (model = 0x14) and later actually support it.
595 	 * (AMD Erratum #110, docId: 25759).
596 	 */
597 	if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
598 		clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
599 		if (!rdmsrl_amd_safe(0xc001100d, &value)) {
600 			value &= ~BIT_64(32);
601 			wrmsrl_amd_safe(0xc001100d, value);
602 		}
603 	}
604 
605 	if (!c->x86_model_id[0])
606 		strcpy(c->x86_model_id, "Hammer");
607 
608 #ifdef CONFIG_SMP
609 	/*
610 	 * Disable TLB flush filter by setting HWCR.FFDIS on K8
611 	 * bit 6 of msr C001_0015
612 	 *
613 	 * Errata 63 for SH-B3 steppings
614 	 * Errata 122 for all steppings (F+ have it disabled by default)
615 	 */
616 	msr_set_bit(MSR_K7_HWCR, 6);
617 #endif
618 }
619 
620 static void init_amd_gh(struct cpuinfo_x86 *c)
621 {
622 #ifdef CONFIG_X86_64
623 	/* do this for boot cpu */
624 	if (c == &boot_cpu_data)
625 		check_enable_amd_mmconf_dmi();
626 
627 	fam10h_check_enable_mmcfg();
628 #endif
629 
630 	/*
631 	 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
632 	 * is always needed when GART is enabled, even in a kernel which has no
633 	 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
634 	 * If it doesn't, we do it here as suggested by the BKDG.
635 	 *
636 	 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
637 	 */
638 	msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
639 
640 	/*
641 	 * On family 10h BIOS may not have properly enabled WC+ support, causing
642 	 * it to be converted to CD memtype. This may result in performance
643 	 * degradation for certain nested-paging guests. Prevent this conversion
644 	 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
645 	 *
646 	 * NOTE: we want to use the _safe accessors so as not to #GP kvm
647 	 * guests on older kvm hosts.
648 	 */
649 	msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
650 
651 	if (cpu_has_amd_erratum(c, amd_erratum_383))
652 		set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
653 }
654 
655 static void init_amd_bd(struct cpuinfo_x86 *c)
656 {
657 	u64 value;
658 
659 	/* re-enable TopologyExtensions if switched off by BIOS */
660 	if ((c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
661 	    !cpu_has(c, X86_FEATURE_TOPOEXT)) {
662 
663 		if (msr_set_bit(0xc0011005, 54) > 0) {
664 			rdmsrl(0xc0011005, value);
665 			if (value & BIT_64(54)) {
666 				set_cpu_cap(c, X86_FEATURE_TOPOEXT);
667 				pr_info(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
668 			}
669 		}
670 	}
671 
672 	/*
673 	 * The way access filter has a performance penalty on some workloads.
674 	 * Disable it on the affected CPUs.
675 	 */
676 	if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
677 		if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
678 			value |= 0x1E;
679 			wrmsrl_safe(MSR_F15H_IC_CFG, value);
680 		}
681 	}
682 }
683 
684 static void init_amd(struct cpuinfo_x86 *c)
685 {
686 	u32 dummy;
687 
688 	early_init_amd(c);
689 
690 	/*
691 	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
692 	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
693 	 */
694 	clear_cpu_cap(c, 0*32+31);
695 
696 	if (c->x86 >= 0x10)
697 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
698 
699 	/* get apicid instead of initial apic id from cpuid */
700 	c->apicid = hard_smp_processor_id();
701 
702 	/* K6s reports MCEs but don't actually have all the MSRs */
703 	if (c->x86 < 6)
704 		clear_cpu_cap(c, X86_FEATURE_MCE);
705 
706 	switch (c->x86) {
707 	case 4:    init_amd_k5(c); break;
708 	case 5:    init_amd_k6(c); break;
709 	case 6:	   init_amd_k7(c); break;
710 	case 0xf:  init_amd_k8(c); break;
711 	case 0x10: init_amd_gh(c); break;
712 	case 0x15: init_amd_bd(c); break;
713 	}
714 
715 	/* Enable workaround for FXSAVE leak */
716 	if (c->x86 >= 6)
717 		set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
718 
719 	cpu_detect_cache_sizes(c);
720 
721 	/* Multi core CPU? */
722 	if (c->extended_cpuid_level >= 0x80000008) {
723 		amd_detect_cmp(c);
724 		srat_detect_node(c);
725 	}
726 
727 #ifdef CONFIG_X86_32
728 	detect_ht(c);
729 #endif
730 
731 	init_amd_cacheinfo(c);
732 
733 	if (c->x86 >= 0xf)
734 		set_cpu_cap(c, X86_FEATURE_K8);
735 
736 	if (cpu_has_xmm2) {
737 		/* MFENCE stops RDTSC speculation */
738 		set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
739 	}
740 
741 	/*
742 	 * Family 0x12 and above processors have APIC timer
743 	 * running in deep C states.
744 	 */
745 	if (c->x86 > 0x11)
746 		set_cpu_cap(c, X86_FEATURE_ARAT);
747 
748 	if (cpu_has_amd_erratum(c, amd_erratum_400))
749 		set_cpu_bug(c, X86_BUG_AMD_APIC_C1E);
750 
751 	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
752 
753 	/* 3DNow or LM implies PREFETCHW */
754 	if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
755 		if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
756 			set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
757 
758 	/* AMD CPUs don't reset SS attributes on SYSRET */
759 	set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
760 }
761 
762 #ifdef CONFIG_X86_32
763 static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
764 {
765 	/* AMD errata T13 (order #21922) */
766 	if ((c->x86 == 6)) {
767 		/* Duron Rev A0 */
768 		if (c->x86_model == 3 && c->x86_mask == 0)
769 			size = 64;
770 		/* Tbird rev A1/A2 */
771 		if (c->x86_model == 4 &&
772 			(c->x86_mask == 0 || c->x86_mask == 1))
773 			size = 256;
774 	}
775 	return size;
776 }
777 #endif
778 
779 static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
780 {
781 	u32 ebx, eax, ecx, edx;
782 	u16 mask = 0xfff;
783 
784 	if (c->x86 < 0xf)
785 		return;
786 
787 	if (c->extended_cpuid_level < 0x80000006)
788 		return;
789 
790 	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
791 
792 	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
793 	tlb_lli_4k[ENTRIES] = ebx & mask;
794 
795 	/*
796 	 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
797 	 * characteristics from the CPUID function 0x80000005 instead.
798 	 */
799 	if (c->x86 == 0xf) {
800 		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
801 		mask = 0xff;
802 	}
803 
804 	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
805 	if (!((eax >> 16) & mask))
806 		tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
807 	else
808 		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
809 
810 	/* a 4M entry uses two 2M entries */
811 	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
812 
813 	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
814 	if (!(eax & mask)) {
815 		/* Erratum 658 */
816 		if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
817 			tlb_lli_2m[ENTRIES] = 1024;
818 		} else {
819 			cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
820 			tlb_lli_2m[ENTRIES] = eax & 0xff;
821 		}
822 	} else
823 		tlb_lli_2m[ENTRIES] = eax & mask;
824 
825 	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
826 }
827 
828 static const struct cpu_dev amd_cpu_dev = {
829 	.c_vendor	= "AMD",
830 	.c_ident	= { "AuthenticAMD" },
831 #ifdef CONFIG_X86_32
832 	.legacy_models = {
833 		{ .family = 4, .model_names =
834 		  {
835 			  [3] = "486 DX/2",
836 			  [7] = "486 DX/2-WB",
837 			  [8] = "486 DX/4",
838 			  [9] = "486 DX/4-WB",
839 			  [14] = "Am5x86-WT",
840 			  [15] = "Am5x86-WB"
841 		  }
842 		},
843 	},
844 	.legacy_cache_size = amd_size_cache,
845 #endif
846 	.c_early_init   = early_init_amd,
847 	.c_detect_tlb	= cpu_detect_tlb_amd,
848 	.c_bsp_init	= bsp_init_amd,
849 	.c_init		= init_amd,
850 	.c_x86_vendor	= X86_VENDOR_AMD,
851 };
852 
853 cpu_dev_register(amd_cpu_dev);
854 
855 /*
856  * AMD errata checking
857  *
858  * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
859  * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
860  * have an OSVW id assigned, which it takes as first argument. Both take a
861  * variable number of family-specific model-stepping ranges created by
862  * AMD_MODEL_RANGE().
863  *
864  * Example:
865  *
866  * const int amd_erratum_319[] =
867  *	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
868  *			   AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
869  *			   AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
870  */
871 
872 #define AMD_LEGACY_ERRATUM(...)		{ -1, __VA_ARGS__, 0 }
873 #define AMD_OSVW_ERRATUM(osvw_id, ...)	{ osvw_id, __VA_ARGS__, 0 }
874 #define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
875 	((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
876 #define AMD_MODEL_RANGE_FAMILY(range)	(((range) >> 24) & 0xff)
877 #define AMD_MODEL_RANGE_START(range)	(((range) >> 12) & 0xfff)
878 #define AMD_MODEL_RANGE_END(range)	((range) & 0xfff)
879 
880 static const int amd_erratum_400[] =
881 	AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
882 			    AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
883 
884 static const int amd_erratum_383[] =
885 	AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
886 
887 
888 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
889 {
890 	int osvw_id = *erratum++;
891 	u32 range;
892 	u32 ms;
893 
894 	if (osvw_id >= 0 && osvw_id < 65536 &&
895 	    cpu_has(cpu, X86_FEATURE_OSVW)) {
896 		u64 osvw_len;
897 
898 		rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
899 		if (osvw_id < osvw_len) {
900 			u64 osvw_bits;
901 
902 			rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
903 			    osvw_bits);
904 			return osvw_bits & (1ULL << (osvw_id & 0x3f));
905 		}
906 	}
907 
908 	/* OSVW unavailable or ID unknown, match family-model-stepping range */
909 	ms = (cpu->x86_model << 4) | cpu->x86_mask;
910 	while ((range = *erratum++))
911 		if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
912 		    (ms >= AMD_MODEL_RANGE_START(range)) &&
913 		    (ms <= AMD_MODEL_RANGE_END(range)))
914 			return true;
915 
916 	return false;
917 }
918 
919 void set_dr_addr_mask(unsigned long mask, int dr)
920 {
921 	if (!boot_cpu_has(X86_FEATURE_BPEXT))
922 		return;
923 
924 	switch (dr) {
925 	case 0:
926 		wrmsr(MSR_F16H_DR0_ADDR_MASK, mask, 0);
927 		break;
928 	case 1:
929 	case 2:
930 	case 3:
931 		wrmsr(MSR_F16H_DR1_ADDR_MASK - 1 + dr, mask, 0);
932 		break;
933 	default:
934 		break;
935 	}
936 }
937