xref: /openbmc/linux/arch/x86/kernel/cpu/amd.c (revision c67ce71d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/export.h>
3 #include <linux/bitops.h>
4 #include <linux/elf.h>
5 #include <linux/mm.h>
6 
7 #include <linux/io.h>
8 #include <linux/sched.h>
9 #include <linux/sched/clock.h>
10 #include <linux/random.h>
11 #include <linux/topology.h>
12 #include <asm/processor.h>
13 #include <asm/apic.h>
14 #include <asm/cacheinfo.h>
15 #include <asm/cpu.h>
16 #include <asm/spec-ctrl.h>
17 #include <asm/smp.h>
18 #include <asm/numa.h>
19 #include <asm/pci-direct.h>
20 #include <asm/delay.h>
21 #include <asm/debugreg.h>
22 #include <asm/resctrl.h>
23 
24 #ifdef CONFIG_X86_64
25 # include <asm/mmconfig.h>
26 #endif
27 
28 #include "cpu.h"
29 
30 /*
31  * nodes_per_socket: Stores the number of nodes per socket.
32  * Refer to Fam15h Models 00-0fh BKDG - CPUID Fn8000_001E_ECX
33  * Node Identifiers[10:8]
34  */
35 static u32 nodes_per_socket = 1;
36 
37 /*
38  * AMD errata checking
39  *
40  * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
41  * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
42  * have an OSVW id assigned, which it takes as first argument. Both take a
43  * variable number of family-specific model-stepping ranges created by
44  * AMD_MODEL_RANGE().
45  *
46  * Example:
47  *
48  * const int amd_erratum_319[] =
49  *	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
50  *			   AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
51  *			   AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
52  */
53 
54 #define AMD_LEGACY_ERRATUM(...)		{ -1, __VA_ARGS__, 0 }
55 #define AMD_OSVW_ERRATUM(osvw_id, ...)	{ osvw_id, __VA_ARGS__, 0 }
56 #define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
57 	((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
58 #define AMD_MODEL_RANGE_FAMILY(range)	(((range) >> 24) & 0xff)
59 #define AMD_MODEL_RANGE_START(range)	(((range) >> 12) & 0xfff)
60 #define AMD_MODEL_RANGE_END(range)	((range) & 0xfff)
61 
62 static const int amd_erratum_400[] =
63 	AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
64 			    AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
65 
66 static const int amd_erratum_383[] =
67 	AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
68 
69 static const int amd_erratum_1485[] =
70 	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x19, 0x10, 0x0, 0x1f, 0xf),
71 			   AMD_MODEL_RANGE(0x19, 0x60, 0x0, 0xaf, 0xf));
72 
73 static bool cpu_has_amd_erratum(struct cpuinfo_x86 *cpu, const int *erratum)
74 {
75 	int osvw_id = *erratum++;
76 	u32 range;
77 	u32 ms;
78 
79 	if (osvw_id >= 0 && osvw_id < 65536 &&
80 	    cpu_has(cpu, X86_FEATURE_OSVW)) {
81 		u64 osvw_len;
82 
83 		rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
84 		if (osvw_id < osvw_len) {
85 			u64 osvw_bits;
86 
87 			rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
88 			    osvw_bits);
89 			return osvw_bits & (1ULL << (osvw_id & 0x3f));
90 		}
91 	}
92 
93 	/* OSVW unavailable or ID unknown, match family-model-stepping range */
94 	ms = (cpu->x86_model << 4) | cpu->x86_stepping;
95 	while ((range = *erratum++))
96 		if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
97 		    (ms >= AMD_MODEL_RANGE_START(range)) &&
98 		    (ms <= AMD_MODEL_RANGE_END(range)))
99 			return true;
100 
101 	return false;
102 }
103 
104 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
105 {
106 	u32 gprs[8] = { 0 };
107 	int err;
108 
109 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
110 		  "%s should only be used on K8!\n", __func__);
111 
112 	gprs[1] = msr;
113 	gprs[7] = 0x9c5a203a;
114 
115 	err = rdmsr_safe_regs(gprs);
116 
117 	*p = gprs[0] | ((u64)gprs[2] << 32);
118 
119 	return err;
120 }
121 
122 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
123 {
124 	u32 gprs[8] = { 0 };
125 
126 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
127 		  "%s should only be used on K8!\n", __func__);
128 
129 	gprs[0] = (u32)val;
130 	gprs[1] = msr;
131 	gprs[2] = val >> 32;
132 	gprs[7] = 0x9c5a203a;
133 
134 	return wrmsr_safe_regs(gprs);
135 }
136 
137 /*
138  *	B step AMD K6 before B 9730xxxx have hardware bugs that can cause
139  *	misexecution of code under Linux. Owners of such processors should
140  *	contact AMD for precise details and a CPU swap.
141  *
142  *	See	http://www.multimania.com/poulot/k6bug.html
143  *	and	section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
144  *		(Publication # 21266  Issue Date: August 1998)
145  *
146  *	The following test is erm.. interesting. AMD neglected to up
147  *	the chip setting when fixing the bug but they also tweaked some
148  *	performance at the same time..
149  */
150 
151 #ifdef CONFIG_X86_32
152 extern __visible void vide(void);
153 __asm__(".text\n"
154 	".globl vide\n"
155 	".type vide, @function\n"
156 	".align 4\n"
157 	"vide: ret\n");
158 #endif
159 
160 static void init_amd_k5(struct cpuinfo_x86 *c)
161 {
162 #ifdef CONFIG_X86_32
163 /*
164  * General Systems BIOSen alias the cpu frequency registers
165  * of the Elan at 0x000df000. Unfortunately, one of the Linux
166  * drivers subsequently pokes it, and changes the CPU speed.
167  * Workaround : Remove the unneeded alias.
168  */
169 #define CBAR		(0xfffc) /* Configuration Base Address  (32-bit) */
170 #define CBAR_ENB	(0x80000000)
171 #define CBAR_KEY	(0X000000CB)
172 	if (c->x86_model == 9 || c->x86_model == 10) {
173 		if (inl(CBAR) & CBAR_ENB)
174 			outl(0 | CBAR_KEY, CBAR);
175 	}
176 #endif
177 }
178 
179 static void init_amd_k6(struct cpuinfo_x86 *c)
180 {
181 #ifdef CONFIG_X86_32
182 	u32 l, h;
183 	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
184 
185 	if (c->x86_model < 6) {
186 		/* Based on AMD doc 20734R - June 2000 */
187 		if (c->x86_model == 0) {
188 			clear_cpu_cap(c, X86_FEATURE_APIC);
189 			set_cpu_cap(c, X86_FEATURE_PGE);
190 		}
191 		return;
192 	}
193 
194 	if (c->x86_model == 6 && c->x86_stepping == 1) {
195 		const int K6_BUG_LOOP = 1000000;
196 		int n;
197 		void (*f_vide)(void);
198 		u64 d, d2;
199 
200 		pr_info("AMD K6 stepping B detected - ");
201 
202 		/*
203 		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
204 		 * calls at the same time.
205 		 */
206 
207 		n = K6_BUG_LOOP;
208 		f_vide = vide;
209 		OPTIMIZER_HIDE_VAR(f_vide);
210 		d = rdtsc();
211 		while (n--)
212 			f_vide();
213 		d2 = rdtsc();
214 		d = d2-d;
215 
216 		if (d > 20*K6_BUG_LOOP)
217 			pr_cont("system stability may be impaired when more than 32 MB are used.\n");
218 		else
219 			pr_cont("probably OK (after B9730xxxx).\n");
220 	}
221 
222 	/* K6 with old style WHCR */
223 	if (c->x86_model < 8 ||
224 	   (c->x86_model == 8 && c->x86_stepping < 8)) {
225 		/* We can only write allocate on the low 508Mb */
226 		if (mbytes > 508)
227 			mbytes = 508;
228 
229 		rdmsr(MSR_K6_WHCR, l, h);
230 		if ((l&0x0000FFFF) == 0) {
231 			unsigned long flags;
232 			l = (1<<0)|((mbytes/4)<<1);
233 			local_irq_save(flags);
234 			wbinvd();
235 			wrmsr(MSR_K6_WHCR, l, h);
236 			local_irq_restore(flags);
237 			pr_info("Enabling old style K6 write allocation for %d Mb\n",
238 				mbytes);
239 		}
240 		return;
241 	}
242 
243 	if ((c->x86_model == 8 && c->x86_stepping > 7) ||
244 	     c->x86_model == 9 || c->x86_model == 13) {
245 		/* The more serious chips .. */
246 
247 		if (mbytes > 4092)
248 			mbytes = 4092;
249 
250 		rdmsr(MSR_K6_WHCR, l, h);
251 		if ((l&0xFFFF0000) == 0) {
252 			unsigned long flags;
253 			l = ((mbytes>>2)<<22)|(1<<16);
254 			local_irq_save(flags);
255 			wbinvd();
256 			wrmsr(MSR_K6_WHCR, l, h);
257 			local_irq_restore(flags);
258 			pr_info("Enabling new style K6 write allocation for %d Mb\n",
259 				mbytes);
260 		}
261 
262 		return;
263 	}
264 
265 	if (c->x86_model == 10) {
266 		/* AMD Geode LX is model 10 */
267 		/* placeholder for any needed mods */
268 		return;
269 	}
270 #endif
271 }
272 
273 static void init_amd_k7(struct cpuinfo_x86 *c)
274 {
275 #ifdef CONFIG_X86_32
276 	u32 l, h;
277 
278 	/*
279 	 * Bit 15 of Athlon specific MSR 15, needs to be 0
280 	 * to enable SSE on Palomino/Morgan/Barton CPU's.
281 	 * If the BIOS didn't enable it already, enable it here.
282 	 */
283 	if (c->x86_model >= 6 && c->x86_model <= 10) {
284 		if (!cpu_has(c, X86_FEATURE_XMM)) {
285 			pr_info("Enabling disabled K7/SSE Support.\n");
286 			msr_clear_bit(MSR_K7_HWCR, 15);
287 			set_cpu_cap(c, X86_FEATURE_XMM);
288 		}
289 	}
290 
291 	/*
292 	 * It's been determined by AMD that Athlons since model 8 stepping 1
293 	 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
294 	 * As per AMD technical note 27212 0.2
295 	 */
296 	if ((c->x86_model == 8 && c->x86_stepping >= 1) || (c->x86_model > 8)) {
297 		rdmsr(MSR_K7_CLK_CTL, l, h);
298 		if ((l & 0xfff00000) != 0x20000000) {
299 			pr_info("CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
300 				l, ((l & 0x000fffff)|0x20000000));
301 			wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
302 		}
303 	}
304 
305 	/* calling is from identify_secondary_cpu() ? */
306 	if (!c->cpu_index)
307 		return;
308 
309 	/*
310 	 * Certain Athlons might work (for various values of 'work') in SMP
311 	 * but they are not certified as MP capable.
312 	 */
313 	/* Athlon 660/661 is valid. */
314 	if ((c->x86_model == 6) && ((c->x86_stepping == 0) ||
315 	    (c->x86_stepping == 1)))
316 		return;
317 
318 	/* Duron 670 is valid */
319 	if ((c->x86_model == 7) && (c->x86_stepping == 0))
320 		return;
321 
322 	/*
323 	 * Athlon 662, Duron 671, and Athlon >model 7 have capability
324 	 * bit. It's worth noting that the A5 stepping (662) of some
325 	 * Athlon XP's have the MP bit set.
326 	 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
327 	 * more.
328 	 */
329 	if (((c->x86_model == 6) && (c->x86_stepping >= 2)) ||
330 	    ((c->x86_model == 7) && (c->x86_stepping >= 1)) ||
331 	     (c->x86_model > 7))
332 		if (cpu_has(c, X86_FEATURE_MP))
333 			return;
334 
335 	/* If we get here, not a certified SMP capable AMD system. */
336 
337 	/*
338 	 * Don't taint if we are running SMP kernel on a single non-MP
339 	 * approved Athlon
340 	 */
341 	WARN_ONCE(1, "WARNING: This combination of AMD"
342 		" processors is not suitable for SMP.\n");
343 	add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
344 #endif
345 }
346 
347 #ifdef CONFIG_NUMA
348 /*
349  * To workaround broken NUMA config.  Read the comment in
350  * srat_detect_node().
351  */
352 static int nearby_node(int apicid)
353 {
354 	int i, node;
355 
356 	for (i = apicid - 1; i >= 0; i--) {
357 		node = __apicid_to_node[i];
358 		if (node != NUMA_NO_NODE && node_online(node))
359 			return node;
360 	}
361 	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
362 		node = __apicid_to_node[i];
363 		if (node != NUMA_NO_NODE && node_online(node))
364 			return node;
365 	}
366 	return first_node(node_online_map); /* Shouldn't happen */
367 }
368 #endif
369 
370 /*
371  * Fix up cpu_core_id for pre-F17h systems to be in the
372  * [0 .. cores_per_node - 1] range. Not really needed but
373  * kept so as not to break existing setups.
374  */
375 static void legacy_fixup_core_id(struct cpuinfo_x86 *c)
376 {
377 	u32 cus_per_node;
378 
379 	if (c->x86 >= 0x17)
380 		return;
381 
382 	cus_per_node = c->x86_max_cores / nodes_per_socket;
383 	c->cpu_core_id %= cus_per_node;
384 }
385 
386 /*
387  * Fixup core topology information for
388  * (1) AMD multi-node processors
389  *     Assumption: Number of cores in each internal node is the same.
390  * (2) AMD processors supporting compute units
391  */
392 static void amd_get_topology(struct cpuinfo_x86 *c)
393 {
394 	int cpu = smp_processor_id();
395 
396 	/* get information required for multi-node processors */
397 	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
398 		int err;
399 		u32 eax, ebx, ecx, edx;
400 
401 		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
402 
403 		c->cpu_die_id  = ecx & 0xff;
404 
405 		if (c->x86 == 0x15)
406 			c->cu_id = ebx & 0xff;
407 
408 		if (c->x86 >= 0x17) {
409 			c->cpu_core_id = ebx & 0xff;
410 
411 			if (smp_num_siblings > 1)
412 				c->x86_max_cores /= smp_num_siblings;
413 		}
414 
415 		/*
416 		 * In case leaf B is available, use it to derive
417 		 * topology information.
418 		 */
419 		err = detect_extended_topology(c);
420 		if (!err)
421 			c->x86_coreid_bits = get_count_order(c->x86_max_cores);
422 
423 		cacheinfo_amd_init_llc_id(c, cpu);
424 
425 	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
426 		u64 value;
427 
428 		rdmsrl(MSR_FAM10H_NODE_ID, value);
429 		c->cpu_die_id = value & 7;
430 
431 		per_cpu(cpu_llc_id, cpu) = c->cpu_die_id;
432 	} else
433 		return;
434 
435 	if (nodes_per_socket > 1) {
436 		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
437 		legacy_fixup_core_id(c);
438 	}
439 }
440 
441 /*
442  * On a AMD dual core setup the lower bits of the APIC id distinguish the cores.
443  * Assumes number of cores is a power of two.
444  */
445 static void amd_detect_cmp(struct cpuinfo_x86 *c)
446 {
447 	unsigned bits;
448 	int cpu = smp_processor_id();
449 
450 	bits = c->x86_coreid_bits;
451 	/* Low order bits define the core id (index of core in socket) */
452 	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
453 	/* Convert the initial APIC ID into the socket ID */
454 	c->phys_proc_id = c->initial_apicid >> bits;
455 	/* use socket ID also for last level cache */
456 	per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id;
457 }
458 
459 u32 amd_get_nodes_per_socket(void)
460 {
461 	return nodes_per_socket;
462 }
463 EXPORT_SYMBOL_GPL(amd_get_nodes_per_socket);
464 
465 static void srat_detect_node(struct cpuinfo_x86 *c)
466 {
467 #ifdef CONFIG_NUMA
468 	int cpu = smp_processor_id();
469 	int node;
470 	unsigned apicid = c->apicid;
471 
472 	node = numa_cpu_node(cpu);
473 	if (node == NUMA_NO_NODE)
474 		node = get_llc_id(cpu);
475 
476 	/*
477 	 * On multi-fabric platform (e.g. Numascale NumaChip) a
478 	 * platform-specific handler needs to be called to fixup some
479 	 * IDs of the CPU.
480 	 */
481 	if (x86_cpuinit.fixup_cpu_id)
482 		x86_cpuinit.fixup_cpu_id(c, node);
483 
484 	if (!node_online(node)) {
485 		/*
486 		 * Two possibilities here:
487 		 *
488 		 * - The CPU is missing memory and no node was created.  In
489 		 *   that case try picking one from a nearby CPU.
490 		 *
491 		 * - The APIC IDs differ from the HyperTransport node IDs
492 		 *   which the K8 northbridge parsing fills in.  Assume
493 		 *   they are all increased by a constant offset, but in
494 		 *   the same order as the HT nodeids.  If that doesn't
495 		 *   result in a usable node fall back to the path for the
496 		 *   previous case.
497 		 *
498 		 * This workaround operates directly on the mapping between
499 		 * APIC ID and NUMA node, assuming certain relationship
500 		 * between APIC ID, HT node ID and NUMA topology.  As going
501 		 * through CPU mapping may alter the outcome, directly
502 		 * access __apicid_to_node[].
503 		 */
504 		int ht_nodeid = c->initial_apicid;
505 
506 		if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
507 			node = __apicid_to_node[ht_nodeid];
508 		/* Pick a nearby node */
509 		if (!node_online(node))
510 			node = nearby_node(apicid);
511 	}
512 	numa_set_node(cpu, node);
513 #endif
514 }
515 
516 static void early_init_amd_mc(struct cpuinfo_x86 *c)
517 {
518 #ifdef CONFIG_SMP
519 	unsigned bits, ecx;
520 
521 	/* Multi core CPU? */
522 	if (c->extended_cpuid_level < 0x80000008)
523 		return;
524 
525 	ecx = cpuid_ecx(0x80000008);
526 
527 	c->x86_max_cores = (ecx & 0xff) + 1;
528 
529 	/* CPU telling us the core id bits shift? */
530 	bits = (ecx >> 12) & 0xF;
531 
532 	/* Otherwise recompute */
533 	if (bits == 0) {
534 		while ((1 << bits) < c->x86_max_cores)
535 			bits++;
536 	}
537 
538 	c->x86_coreid_bits = bits;
539 #endif
540 }
541 
542 static void bsp_init_amd(struct cpuinfo_x86 *c)
543 {
544 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
545 
546 		if (c->x86 > 0x10 ||
547 		    (c->x86 == 0x10 && c->x86_model >= 0x2)) {
548 			u64 val;
549 
550 			rdmsrl(MSR_K7_HWCR, val);
551 			if (!(val & BIT(24)))
552 				pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n");
553 		}
554 	}
555 
556 	if (c->x86 == 0x15) {
557 		unsigned long upperbit;
558 		u32 cpuid, assoc;
559 
560 		cpuid	 = cpuid_edx(0x80000005);
561 		assoc	 = cpuid >> 16 & 0xff;
562 		upperbit = ((cpuid >> 24) << 10) / assoc;
563 
564 		va_align.mask	  = (upperbit - 1) & PAGE_MASK;
565 		va_align.flags    = ALIGN_VA_32 | ALIGN_VA_64;
566 
567 		/* A random value per boot for bit slice [12:upper_bit) */
568 		va_align.bits = get_random_u32() & va_align.mask;
569 	}
570 
571 	if (cpu_has(c, X86_FEATURE_MWAITX))
572 		use_mwaitx_delay();
573 
574 	if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
575 		u32 ecx;
576 
577 		ecx = cpuid_ecx(0x8000001e);
578 		__max_die_per_package = nodes_per_socket = ((ecx >> 8) & 7) + 1;
579 	} else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) {
580 		u64 value;
581 
582 		rdmsrl(MSR_FAM10H_NODE_ID, value);
583 		__max_die_per_package = nodes_per_socket = ((value >> 3) & 7) + 1;
584 	}
585 
586 	if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) &&
587 	    !boot_cpu_has(X86_FEATURE_VIRT_SSBD) &&
588 	    c->x86 >= 0x15 && c->x86 <= 0x17) {
589 		unsigned int bit;
590 
591 		switch (c->x86) {
592 		case 0x15: bit = 54; break;
593 		case 0x16: bit = 33; break;
594 		case 0x17: bit = 10; break;
595 		default: return;
596 		}
597 		/*
598 		 * Try to cache the base value so further operations can
599 		 * avoid RMW. If that faults, do not enable SSBD.
600 		 */
601 		if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) {
602 			setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD);
603 			setup_force_cpu_cap(X86_FEATURE_SSBD);
604 			x86_amd_ls_cfg_ssbd_mask = 1ULL << bit;
605 		}
606 	}
607 
608 	resctrl_cpu_detect(c);
609 
610 	/* Figure out Zen generations: */
611 	switch (c->x86) {
612 	case 0x17: {
613 		switch (c->x86_model) {
614 		case 0x00 ... 0x2f:
615 		case 0x50 ... 0x5f:
616 			setup_force_cpu_cap(X86_FEATURE_ZEN1);
617 			break;
618 		case 0x30 ... 0x4f:
619 		case 0x60 ... 0x7f:
620 		case 0x90 ... 0x91:
621 		case 0xa0 ... 0xaf:
622 			setup_force_cpu_cap(X86_FEATURE_ZEN2);
623 			break;
624 		default:
625 			goto warn;
626 		}
627 		break;
628 	}
629 	case 0x19: {
630 		switch (c->x86_model) {
631 		case 0x00 ... 0x0f:
632 		case 0x20 ... 0x5f:
633 			setup_force_cpu_cap(X86_FEATURE_ZEN3);
634 			break;
635 		case 0x10 ... 0x1f:
636 		case 0x60 ... 0xaf:
637 			setup_force_cpu_cap(X86_FEATURE_ZEN4);
638 			break;
639 		default:
640 			goto warn;
641 		}
642 		break;
643 	}
644 	default:
645 		break;
646 	}
647 
648 	return;
649 
650 warn:
651 	WARN_ONCE(1, "Family 0x%x, model: 0x%x??\n", c->x86, c->x86_model);
652 }
653 
654 static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
655 {
656 	u64 msr;
657 
658 	/*
659 	 * BIOS support is required for SME and SEV.
660 	 *   For SME: If BIOS has enabled SME then adjust x86_phys_bits by
661 	 *	      the SME physical address space reduction value.
662 	 *	      If BIOS has not enabled SME then don't advertise the
663 	 *	      SME feature (set in scattered.c).
664 	 *	      If the kernel has not enabled SME via any means then
665 	 *	      don't advertise the SME feature.
666 	 *   For SEV: If BIOS has not enabled SEV then don't advertise the
667 	 *            SEV and SEV_ES feature (set in scattered.c).
668 	 *
669 	 *   In all cases, since support for SME and SEV requires long mode,
670 	 *   don't advertise the feature under CONFIG_X86_32.
671 	 */
672 	if (cpu_has(c, X86_FEATURE_SME) || cpu_has(c, X86_FEATURE_SEV)) {
673 		/* Check if memory encryption is enabled */
674 		rdmsrl(MSR_AMD64_SYSCFG, msr);
675 		if (!(msr & MSR_AMD64_SYSCFG_MEM_ENCRYPT))
676 			goto clear_all;
677 
678 		/*
679 		 * Always adjust physical address bits. Even though this
680 		 * will be a value above 32-bits this is still done for
681 		 * CONFIG_X86_32 so that accurate values are reported.
682 		 */
683 		c->x86_phys_bits -= (cpuid_ebx(0x8000001f) >> 6) & 0x3f;
684 
685 		if (IS_ENABLED(CONFIG_X86_32))
686 			goto clear_all;
687 
688 		if (!sme_me_mask)
689 			setup_clear_cpu_cap(X86_FEATURE_SME);
690 
691 		rdmsrl(MSR_K7_HWCR, msr);
692 		if (!(msr & MSR_K7_HWCR_SMMLOCK))
693 			goto clear_sev;
694 
695 		return;
696 
697 clear_all:
698 		setup_clear_cpu_cap(X86_FEATURE_SME);
699 clear_sev:
700 		setup_clear_cpu_cap(X86_FEATURE_SEV);
701 		setup_clear_cpu_cap(X86_FEATURE_SEV_ES);
702 	}
703 }
704 
705 static void early_init_amd(struct cpuinfo_x86 *c)
706 {
707 	u64 value;
708 	u32 dummy;
709 
710 	early_init_amd_mc(c);
711 
712 	if (c->x86 >= 0xf)
713 		set_cpu_cap(c, X86_FEATURE_K8);
714 
715 	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
716 
717 	/*
718 	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
719 	 * with P/T states and does not stop in deep C-states
720 	 */
721 	if (c->x86_power & (1 << 8)) {
722 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
723 		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
724 	}
725 
726 	/* Bit 12 of 8000_0007 edx is accumulated power mechanism. */
727 	if (c->x86_power & BIT(12))
728 		set_cpu_cap(c, X86_FEATURE_ACC_POWER);
729 
730 	/* Bit 14 indicates the Runtime Average Power Limit interface. */
731 	if (c->x86_power & BIT(14))
732 		set_cpu_cap(c, X86_FEATURE_RAPL);
733 
734 #ifdef CONFIG_X86_64
735 	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
736 #else
737 	/*  Set MTRR capability flag if appropriate */
738 	if (c->x86 == 5)
739 		if (c->x86_model == 13 || c->x86_model == 9 ||
740 		    (c->x86_model == 8 && c->x86_stepping >= 8))
741 			set_cpu_cap(c, X86_FEATURE_K6_MTRR);
742 #endif
743 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
744 	/*
745 	 * ApicID can always be treated as an 8-bit value for AMD APIC versions
746 	 * >= 0x10, but even old K8s came out of reset with version 0x10. So, we
747 	 * can safely set X86_FEATURE_EXTD_APICID unconditionally for families
748 	 * after 16h.
749 	 */
750 	if (boot_cpu_has(X86_FEATURE_APIC)) {
751 		if (c->x86 > 0x16)
752 			set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
753 		else if (c->x86 >= 0xf) {
754 			/* check CPU config space for extended APIC ID */
755 			unsigned int val;
756 
757 			val = read_pci_config(0, 24, 0, 0x68);
758 			if ((val >> 17 & 0x3) == 0x3)
759 				set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
760 		}
761 	}
762 #endif
763 
764 	/*
765 	 * This is only needed to tell the kernel whether to use VMCALL
766 	 * and VMMCALL.  VMMCALL is never executed except under virt, so
767 	 * we can set it unconditionally.
768 	 */
769 	set_cpu_cap(c, X86_FEATURE_VMMCALL);
770 
771 	/* F16h erratum 793, CVE-2013-6885 */
772 	if (c->x86 == 0x16 && c->x86_model <= 0xf)
773 		msr_set_bit(MSR_AMD64_LS_CFG, 15);
774 
775 	/*
776 	 * Check whether the machine is affected by erratum 400. This is
777 	 * used to select the proper idle routine and to enable the check
778 	 * whether the machine is affected in arch_post_acpi_init(), which
779 	 * sets the X86_BUG_AMD_APIC_C1E bug depending on the MSR check.
780 	 */
781 	if (cpu_has_amd_erratum(c, amd_erratum_400))
782 		set_cpu_bug(c, X86_BUG_AMD_E400);
783 
784 	early_detect_mem_encrypt(c);
785 
786 	/* Re-enable TopologyExtensions if switched off by BIOS */
787 	if (c->x86 == 0x15 &&
788 	    (c->x86_model >= 0x10 && c->x86_model <= 0x6f) &&
789 	    !cpu_has(c, X86_FEATURE_TOPOEXT)) {
790 
791 		if (msr_set_bit(0xc0011005, 54) > 0) {
792 			rdmsrl(0xc0011005, value);
793 			if (value & BIT_64(54)) {
794 				set_cpu_cap(c, X86_FEATURE_TOPOEXT);
795 				pr_info_once(FW_INFO "CPU: Re-enabling disabled Topology Extensions Support.\n");
796 			}
797 		}
798 	}
799 
800 	if (cpu_has(c, X86_FEATURE_TOPOEXT))
801 		smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1;
802 
803 	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && !cpu_has(c, X86_FEATURE_IBPB_BRTYPE)) {
804 		if (c->x86 == 0x17 && boot_cpu_has(X86_FEATURE_AMD_IBPB))
805 			setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
806 		else if (c->x86 >= 0x19 && !wrmsrl_safe(MSR_IA32_PRED_CMD, PRED_CMD_SBPB)) {
807 			setup_force_cpu_cap(X86_FEATURE_IBPB_BRTYPE);
808 			setup_force_cpu_cap(X86_FEATURE_SBPB);
809 		}
810 	}
811 }
812 
813 static void init_amd_k8(struct cpuinfo_x86 *c)
814 {
815 	u32 level;
816 	u64 value;
817 
818 	/* On C+ stepping K8 rep microcode works well for copy/memset */
819 	level = cpuid_eax(1);
820 	if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
821 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
822 
823 	/*
824 	 * Some BIOSes incorrectly force this feature, but only K8 revision D
825 	 * (model = 0x14) and later actually support it.
826 	 * (AMD Erratum #110, docId: 25759).
827 	 */
828 	if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
829 		clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
830 		if (!rdmsrl_amd_safe(0xc001100d, &value)) {
831 			value &= ~BIT_64(32);
832 			wrmsrl_amd_safe(0xc001100d, value);
833 		}
834 	}
835 
836 	if (!c->x86_model_id[0])
837 		strcpy(c->x86_model_id, "Hammer");
838 
839 #ifdef CONFIG_SMP
840 	/*
841 	 * Disable TLB flush filter by setting HWCR.FFDIS on K8
842 	 * bit 6 of msr C001_0015
843 	 *
844 	 * Errata 63 for SH-B3 steppings
845 	 * Errata 122 for all steppings (F+ have it disabled by default)
846 	 */
847 	msr_set_bit(MSR_K7_HWCR, 6);
848 #endif
849 	set_cpu_bug(c, X86_BUG_SWAPGS_FENCE);
850 }
851 
852 static void init_amd_gh(struct cpuinfo_x86 *c)
853 {
854 #ifdef CONFIG_MMCONF_FAM10H
855 	/* do this for boot cpu */
856 	if (c == &boot_cpu_data)
857 		check_enable_amd_mmconf_dmi();
858 
859 	fam10h_check_enable_mmcfg();
860 #endif
861 
862 	/*
863 	 * Disable GART TLB Walk Errors on Fam10h. We do this here because this
864 	 * is always needed when GART is enabled, even in a kernel which has no
865 	 * MCE support built in. BIOS should disable GartTlbWlk Errors already.
866 	 * If it doesn't, we do it here as suggested by the BKDG.
867 	 *
868 	 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
869 	 */
870 	msr_set_bit(MSR_AMD64_MCx_MASK(4), 10);
871 
872 	/*
873 	 * On family 10h BIOS may not have properly enabled WC+ support, causing
874 	 * it to be converted to CD memtype. This may result in performance
875 	 * degradation for certain nested-paging guests. Prevent this conversion
876 	 * by clearing bit 24 in MSR_AMD64_BU_CFG2.
877 	 *
878 	 * NOTE: we want to use the _safe accessors so as not to #GP kvm
879 	 * guests on older kvm hosts.
880 	 */
881 	msr_clear_bit(MSR_AMD64_BU_CFG2, 24);
882 
883 	if (cpu_has_amd_erratum(c, amd_erratum_383))
884 		set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
885 }
886 
887 static void init_amd_ln(struct cpuinfo_x86 *c)
888 {
889 	/*
890 	 * Apply erratum 665 fix unconditionally so machines without a BIOS
891 	 * fix work.
892 	 */
893 	msr_set_bit(MSR_AMD64_DE_CFG, 31);
894 }
895 
896 static bool rdrand_force;
897 
898 static int __init rdrand_cmdline(char *str)
899 {
900 	if (!str)
901 		return -EINVAL;
902 
903 	if (!strcmp(str, "force"))
904 		rdrand_force = true;
905 	else
906 		return -EINVAL;
907 
908 	return 0;
909 }
910 early_param("rdrand", rdrand_cmdline);
911 
912 static void clear_rdrand_cpuid_bit(struct cpuinfo_x86 *c)
913 {
914 	/*
915 	 * Saving of the MSR used to hide the RDRAND support during
916 	 * suspend/resume is done by arch/x86/power/cpu.c, which is
917 	 * dependent on CONFIG_PM_SLEEP.
918 	 */
919 	if (!IS_ENABLED(CONFIG_PM_SLEEP))
920 		return;
921 
922 	/*
923 	 * The self-test can clear X86_FEATURE_RDRAND, so check for
924 	 * RDRAND support using the CPUID function directly.
925 	 */
926 	if (!(cpuid_ecx(1) & BIT(30)) || rdrand_force)
927 		return;
928 
929 	msr_clear_bit(MSR_AMD64_CPUID_FN_1, 62);
930 
931 	/*
932 	 * Verify that the CPUID change has occurred in case the kernel is
933 	 * running virtualized and the hypervisor doesn't support the MSR.
934 	 */
935 	if (cpuid_ecx(1) & BIT(30)) {
936 		pr_info_once("BIOS may not properly restore RDRAND after suspend, but hypervisor does not support hiding RDRAND via CPUID.\n");
937 		return;
938 	}
939 
940 	clear_cpu_cap(c, X86_FEATURE_RDRAND);
941 	pr_info_once("BIOS may not properly restore RDRAND after suspend, hiding RDRAND via CPUID. Use rdrand=force to reenable.\n");
942 }
943 
944 static void init_amd_jg(struct cpuinfo_x86 *c)
945 {
946 	/*
947 	 * Some BIOS implementations do not restore proper RDRAND support
948 	 * across suspend and resume. Check on whether to hide the RDRAND
949 	 * instruction support via CPUID.
950 	 */
951 	clear_rdrand_cpuid_bit(c);
952 }
953 
954 static void init_amd_bd(struct cpuinfo_x86 *c)
955 {
956 	u64 value;
957 
958 	/*
959 	 * The way access filter has a performance penalty on some workloads.
960 	 * Disable it on the affected CPUs.
961 	 */
962 	if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
963 		if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) {
964 			value |= 0x1E;
965 			wrmsrl_safe(MSR_F15H_IC_CFG, value);
966 		}
967 	}
968 
969 	/*
970 	 * Some BIOS implementations do not restore proper RDRAND support
971 	 * across suspend and resume. Check on whether to hide the RDRAND
972 	 * instruction support via CPUID.
973 	 */
974 	clear_rdrand_cpuid_bit(c);
975 }
976 
977 static void fix_erratum_1386(struct cpuinfo_x86 *c)
978 {
979 	/*
980 	 * Work around Erratum 1386.  The XSAVES instruction malfunctions in
981 	 * certain circumstances on Zen1/2 uarch, and not all parts have had
982 	 * updated microcode at the time of writing (March 2023).
983 	 *
984 	 * Affected parts all have no supervisor XSAVE states, meaning that
985 	 * the XSAVEC instruction (which works fine) is equivalent.
986 	 */
987 	clear_cpu_cap(c, X86_FEATURE_XSAVES);
988 }
989 
990 void init_spectral_chicken(struct cpuinfo_x86 *c)
991 {
992 #ifdef CONFIG_CPU_UNRET_ENTRY
993 	u64 value;
994 
995 	/*
996 	 * On Zen2 we offer this chicken (bit) on the altar of Speculation.
997 	 *
998 	 * This suppresses speculation from the middle of a basic block, i.e. it
999 	 * suppresses non-branch predictions.
1000 	 *
1001 	 * We use STIBP as a heuristic to filter out Zen2 from the rest of F17H
1002 	 */
1003 	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) && cpu_has(c, X86_FEATURE_AMD_STIBP)) {
1004 		if (!rdmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, &value)) {
1005 			value |= MSR_ZEN2_SPECTRAL_CHICKEN_BIT;
1006 			wrmsrl_safe(MSR_ZEN2_SPECTRAL_CHICKEN, value);
1007 		}
1008 	}
1009 #endif
1010 }
1011 
1012 static void init_amd_zn(struct cpuinfo_x86 *c)
1013 {
1014 	setup_force_cpu_cap(X86_FEATURE_ZEN);
1015 #ifdef CONFIG_NUMA
1016 	node_reclaim_distance = 32;
1017 #endif
1018 }
1019 
1020 static void init_amd_zen1(struct cpuinfo_x86 *c)
1021 {
1022 	fix_erratum_1386(c);
1023 
1024 	/* Fix up CPUID bits, but only if not virtualised. */
1025 	if (!cpu_has(c, X86_FEATURE_HYPERVISOR)) {
1026 
1027 		/* Erratum 1076: CPB feature bit not being set in CPUID. */
1028 		if (!cpu_has(c, X86_FEATURE_CPB))
1029 			set_cpu_cap(c, X86_FEATURE_CPB);
1030 
1031 		/*
1032 		 * Zen3 (Fam19 model < 0x10) parts are not susceptible to
1033 		 * Branch Type Confusion, but predate the allocation of the
1034 		 * BTC_NO bit.
1035 		 */
1036 		if (c->x86 == 0x19 && !cpu_has(c, X86_FEATURE_BTC_NO))
1037 			set_cpu_cap(c, X86_FEATURE_BTC_NO);
1038 	}
1039 
1040 	pr_notice_once("AMD Zen1 DIV0 bug detected. Disable SMT for full protection.\n");
1041 	setup_force_cpu_bug(X86_BUG_DIV0);
1042 }
1043 
1044 static bool cpu_has_zenbleed_microcode(void)
1045 {
1046 	u32 good_rev = 0;
1047 
1048 	switch (boot_cpu_data.x86_model) {
1049 	case 0x30 ... 0x3f: good_rev = 0x0830107b; break;
1050 	case 0x60 ... 0x67: good_rev = 0x0860010c; break;
1051 	case 0x68 ... 0x6f: good_rev = 0x08608107; break;
1052 	case 0x70 ... 0x7f: good_rev = 0x08701033; break;
1053 	case 0xa0 ... 0xaf: good_rev = 0x08a00009; break;
1054 
1055 	default:
1056 		return false;
1057 		break;
1058 	}
1059 
1060 	if (boot_cpu_data.microcode < good_rev)
1061 		return false;
1062 
1063 	return true;
1064 }
1065 
1066 static void zen2_zenbleed_check(struct cpuinfo_x86 *c)
1067 {
1068 	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
1069 		return;
1070 
1071 	if (!cpu_has(c, X86_FEATURE_AVX))
1072 		return;
1073 
1074 	if (!cpu_has_zenbleed_microcode()) {
1075 		pr_notice_once("Zenbleed: please update your microcode for the most optimal fix\n");
1076 		msr_set_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
1077 	} else {
1078 		msr_clear_bit(MSR_AMD64_DE_CFG, MSR_AMD64_DE_CFG_ZEN2_FP_BACKUP_FIX_BIT);
1079 	}
1080 }
1081 
1082 static void init_amd_zen2(struct cpuinfo_x86 *c)
1083 {
1084 	fix_erratum_1386(c);
1085 	zen2_zenbleed_check(c);
1086 }
1087 
1088 static void init_amd_zen3(struct cpuinfo_x86 *c)
1089 {
1090 }
1091 
1092 static void init_amd_zen4(struct cpuinfo_x86 *c)
1093 {
1094 }
1095 
1096 static void init_amd(struct cpuinfo_x86 *c)
1097 {
1098 	early_init_amd(c);
1099 
1100 	/*
1101 	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
1102 	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
1103 	 */
1104 	clear_cpu_cap(c, 0*32+31);
1105 
1106 	if (c->x86 >= 0x10)
1107 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
1108 
1109 	/* AMD FSRM also implies FSRS */
1110 	if (cpu_has(c, X86_FEATURE_FSRM))
1111 		set_cpu_cap(c, X86_FEATURE_FSRS);
1112 
1113 	/* get apicid instead of initial apic id from cpuid */
1114 	c->apicid = read_apic_id();
1115 
1116 	/* K6s reports MCEs but don't actually have all the MSRs */
1117 	if (c->x86 < 6)
1118 		clear_cpu_cap(c, X86_FEATURE_MCE);
1119 
1120 	switch (c->x86) {
1121 	case 4:    init_amd_k5(c); break;
1122 	case 5:    init_amd_k6(c); break;
1123 	case 6:	   init_amd_k7(c); break;
1124 	case 0xf:  init_amd_k8(c); break;
1125 	case 0x10: init_amd_gh(c); break;
1126 	case 0x12: init_amd_ln(c); break;
1127 	case 0x15: init_amd_bd(c); break;
1128 	case 0x16: init_amd_jg(c); break;
1129 	case 0x17: init_spectral_chicken(c);
1130 		   fallthrough;
1131 	case 0x19: init_amd_zn(c); break;
1132 	}
1133 
1134 	if (boot_cpu_has(X86_FEATURE_ZEN1))
1135 		init_amd_zen1(c);
1136 	else if (boot_cpu_has(X86_FEATURE_ZEN2))
1137 		init_amd_zen2(c);
1138 	else if (boot_cpu_has(X86_FEATURE_ZEN3))
1139 		init_amd_zen3(c);
1140 	else if (boot_cpu_has(X86_FEATURE_ZEN4))
1141 		init_amd_zen4(c);
1142 
1143 	/*
1144 	 * Enable workaround for FXSAVE leak on CPUs
1145 	 * without a XSaveErPtr feature
1146 	 */
1147 	if ((c->x86 >= 6) && (!cpu_has(c, X86_FEATURE_XSAVEERPTR)))
1148 		set_cpu_bug(c, X86_BUG_FXSAVE_LEAK);
1149 
1150 	cpu_detect_cache_sizes(c);
1151 
1152 	amd_detect_cmp(c);
1153 	amd_get_topology(c);
1154 	srat_detect_node(c);
1155 
1156 	init_amd_cacheinfo(c);
1157 
1158 	if (!cpu_has(c, X86_FEATURE_LFENCE_RDTSC) && cpu_has(c, X86_FEATURE_XMM2)) {
1159 		/*
1160 		 * Use LFENCE for execution serialization.  On families which
1161 		 * don't have that MSR, LFENCE is already serializing.
1162 		 * msr_set_bit() uses the safe accessors, too, even if the MSR
1163 		 * is not present.
1164 		 */
1165 		msr_set_bit(MSR_AMD64_DE_CFG,
1166 			    MSR_AMD64_DE_CFG_LFENCE_SERIALIZE_BIT);
1167 
1168 		/* A serializing LFENCE stops RDTSC speculation */
1169 		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
1170 	}
1171 
1172 	/*
1173 	 * Family 0x12 and above processors have APIC timer
1174 	 * running in deep C states.
1175 	 */
1176 	if (c->x86 > 0x11)
1177 		set_cpu_cap(c, X86_FEATURE_ARAT);
1178 
1179 	/* 3DNow or LM implies PREFETCHW */
1180 	if (!cpu_has(c, X86_FEATURE_3DNOWPREFETCH))
1181 		if (cpu_has(c, X86_FEATURE_3DNOW) || cpu_has(c, X86_FEATURE_LM))
1182 			set_cpu_cap(c, X86_FEATURE_3DNOWPREFETCH);
1183 
1184 	/* AMD CPUs don't reset SS attributes on SYSRET, Xen does. */
1185 	if (!cpu_feature_enabled(X86_FEATURE_XENPV))
1186 		set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS);
1187 
1188 	/*
1189 	 * Turn on the Instructions Retired free counter on machines not
1190 	 * susceptible to erratum #1054 "Instructions Retired Performance
1191 	 * Counter May Be Inaccurate".
1192 	 */
1193 	if (cpu_has(c, X86_FEATURE_IRPERF) &&
1194 	    (boot_cpu_has(X86_FEATURE_ZEN1) && c->x86_model > 0x2f))
1195 		msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_IRPERF_EN_BIT);
1196 
1197 	check_null_seg_clears_base(c);
1198 
1199 	/*
1200 	 * Make sure EFER[AIBRSE - Automatic IBRS Enable] is set. The APs are brought up
1201 	 * using the trampoline code and as part of it, MSR_EFER gets prepared there in
1202 	 * order to be replicated onto them. Regardless, set it here again, if not set,
1203 	 * to protect against any future refactoring/code reorganization which might
1204 	 * miss setting this important bit.
1205 	 */
1206 	if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
1207 	    cpu_has(c, X86_FEATURE_AUTOIBRS))
1208 		WARN_ON_ONCE(msr_set_bit(MSR_EFER, _EFER_AUTOIBRS));
1209 
1210 	if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
1211 	     cpu_has_amd_erratum(c, amd_erratum_1485))
1212 		msr_set_bit(MSR_ZEN4_BP_CFG, MSR_ZEN4_BP_CFG_SHARED_BTB_FIX_BIT);
1213 
1214 	/* AMD CPUs don't need fencing after x2APIC/TSC_DEADLINE MSR writes. */
1215 	clear_cpu_cap(c, X86_FEATURE_APIC_MSRS_FENCE);
1216 }
1217 
1218 #ifdef CONFIG_X86_32
1219 static unsigned int amd_size_cache(struct cpuinfo_x86 *c, unsigned int size)
1220 {
1221 	/* AMD errata T13 (order #21922) */
1222 	if (c->x86 == 6) {
1223 		/* Duron Rev A0 */
1224 		if (c->x86_model == 3 && c->x86_stepping == 0)
1225 			size = 64;
1226 		/* Tbird rev A1/A2 */
1227 		if (c->x86_model == 4 &&
1228 			(c->x86_stepping == 0 || c->x86_stepping == 1))
1229 			size = 256;
1230 	}
1231 	return size;
1232 }
1233 #endif
1234 
1235 static void cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
1236 {
1237 	u32 ebx, eax, ecx, edx;
1238 	u16 mask = 0xfff;
1239 
1240 	if (c->x86 < 0xf)
1241 		return;
1242 
1243 	if (c->extended_cpuid_level < 0x80000006)
1244 		return;
1245 
1246 	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
1247 
1248 	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
1249 	tlb_lli_4k[ENTRIES] = ebx & mask;
1250 
1251 	/*
1252 	 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
1253 	 * characteristics from the CPUID function 0x80000005 instead.
1254 	 */
1255 	if (c->x86 == 0xf) {
1256 		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1257 		mask = 0xff;
1258 	}
1259 
1260 	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1261 	if (!((eax >> 16) & mask))
1262 		tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff;
1263 	else
1264 		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
1265 
1266 	/* a 4M entry uses two 2M entries */
1267 	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
1268 
1269 	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
1270 	if (!(eax & mask)) {
1271 		/* Erratum 658 */
1272 		if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
1273 			tlb_lli_2m[ENTRIES] = 1024;
1274 		} else {
1275 			cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
1276 			tlb_lli_2m[ENTRIES] = eax & 0xff;
1277 		}
1278 	} else
1279 		tlb_lli_2m[ENTRIES] = eax & mask;
1280 
1281 	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
1282 }
1283 
1284 static const struct cpu_dev amd_cpu_dev = {
1285 	.c_vendor	= "AMD",
1286 	.c_ident	= { "AuthenticAMD" },
1287 #ifdef CONFIG_X86_32
1288 	.legacy_models = {
1289 		{ .family = 4, .model_names =
1290 		  {
1291 			  [3] = "486 DX/2",
1292 			  [7] = "486 DX/2-WB",
1293 			  [8] = "486 DX/4",
1294 			  [9] = "486 DX/4-WB",
1295 			  [14] = "Am5x86-WT",
1296 			  [15] = "Am5x86-WB"
1297 		  }
1298 		},
1299 	},
1300 	.legacy_cache_size = amd_size_cache,
1301 #endif
1302 	.c_early_init   = early_init_amd,
1303 	.c_detect_tlb	= cpu_detect_tlb_amd,
1304 	.c_bsp_init	= bsp_init_amd,
1305 	.c_init		= init_amd,
1306 	.c_x86_vendor	= X86_VENDOR_AMD,
1307 };
1308 
1309 cpu_dev_register(amd_cpu_dev);
1310 
1311 static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[4], amd_dr_addr_mask);
1312 
1313 static unsigned int amd_msr_dr_addr_masks[] = {
1314 	MSR_F16H_DR0_ADDR_MASK,
1315 	MSR_F16H_DR1_ADDR_MASK,
1316 	MSR_F16H_DR1_ADDR_MASK + 1,
1317 	MSR_F16H_DR1_ADDR_MASK + 2
1318 };
1319 
1320 void amd_set_dr_addr_mask(unsigned long mask, unsigned int dr)
1321 {
1322 	int cpu = smp_processor_id();
1323 
1324 	if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1325 		return;
1326 
1327 	if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1328 		return;
1329 
1330 	if (per_cpu(amd_dr_addr_mask, cpu)[dr] == mask)
1331 		return;
1332 
1333 	wrmsr(amd_msr_dr_addr_masks[dr], mask, 0);
1334 	per_cpu(amd_dr_addr_mask, cpu)[dr] = mask;
1335 }
1336 
1337 unsigned long amd_get_dr_addr_mask(unsigned int dr)
1338 {
1339 	if (!cpu_feature_enabled(X86_FEATURE_BPEXT))
1340 		return 0;
1341 
1342 	if (WARN_ON_ONCE(dr >= ARRAY_SIZE(amd_msr_dr_addr_masks)))
1343 		return 0;
1344 
1345 	return per_cpu(amd_dr_addr_mask[dr], smp_processor_id());
1346 }
1347 EXPORT_SYMBOL_GPL(amd_get_dr_addr_mask);
1348 
1349 u32 amd_get_highest_perf(void)
1350 {
1351 	struct cpuinfo_x86 *c = &boot_cpu_data;
1352 
1353 	if (c->x86 == 0x17 && ((c->x86_model >= 0x30 && c->x86_model < 0x40) ||
1354 			       (c->x86_model >= 0x70 && c->x86_model < 0x80)))
1355 		return 166;
1356 
1357 	if (c->x86 == 0x19 && ((c->x86_model >= 0x20 && c->x86_model < 0x30) ||
1358 			       (c->x86_model >= 0x40 && c->x86_model < 0x70)))
1359 		return 166;
1360 
1361 	return 255;
1362 }
1363 EXPORT_SYMBOL_GPL(amd_get_highest_perf);
1364 
1365 static void zenbleed_check_cpu(void *unused)
1366 {
1367 	struct cpuinfo_x86 *c = &cpu_data(smp_processor_id());
1368 
1369 	zen2_zenbleed_check(c);
1370 }
1371 
1372 void amd_check_microcode(void)
1373 {
1374 	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
1375 		return;
1376 
1377 	if (cpu_feature_enabled(X86_FEATURE_ZEN2))
1378 		on_each_cpu(zenbleed_check_cpu, NULL, 1);
1379 }
1380 
1381 /*
1382  * Issue a DIV 0/1 insn to clear any division data from previous DIV
1383  * operations.
1384  */
1385 void noinstr amd_clear_divider(void)
1386 {
1387 	asm volatile(ALTERNATIVE("", "div %2\n\t", X86_BUG_DIV0)
1388 		     :: "a" (0), "d" (0), "r" (1));
1389 }
1390 EXPORT_SYMBOL_GPL(amd_clear_divider);
1391