xref: /openbmc/linux/arch/x86/kernel/cpu/amd.c (revision 7b6d864b)
1 #include <linux/export.h>
2 #include <linux/init.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 <asm/processor.h>
10 #include <asm/apic.h>
11 #include <asm/cpu.h>
12 #include <asm/pci-direct.h>
13 
14 #ifdef CONFIG_X86_64
15 # include <asm/mmconfig.h>
16 # include <asm/cacheflush.h>
17 #endif
18 
19 #include "cpu.h"
20 
21 static inline int rdmsrl_amd_safe(unsigned msr, unsigned long long *p)
22 {
23 	u32 gprs[8] = { 0 };
24 	int err;
25 
26 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
27 		  "%s should only be used on K8!\n", __func__);
28 
29 	gprs[1] = msr;
30 	gprs[7] = 0x9c5a203a;
31 
32 	err = rdmsr_safe_regs(gprs);
33 
34 	*p = gprs[0] | ((u64)gprs[2] << 32);
35 
36 	return err;
37 }
38 
39 static inline int wrmsrl_amd_safe(unsigned msr, unsigned long long val)
40 {
41 	u32 gprs[8] = { 0 };
42 
43 	WARN_ONCE((boot_cpu_data.x86 != 0xf),
44 		  "%s should only be used on K8!\n", __func__);
45 
46 	gprs[0] = (u32)val;
47 	gprs[1] = msr;
48 	gprs[2] = val >> 32;
49 	gprs[7] = 0x9c5a203a;
50 
51 	return wrmsr_safe_regs(gprs);
52 }
53 
54 #ifdef CONFIG_X86_32
55 /*
56  *	B step AMD K6 before B 9730xxxx have hardware bugs that can cause
57  *	misexecution of code under Linux. Owners of such processors should
58  *	contact AMD for precise details and a CPU swap.
59  *
60  *	See	http://www.multimania.com/poulot/k6bug.html
61  *	and	section 2.6.2 of "AMD-K6 Processor Revision Guide - Model 6"
62  *		(Publication # 21266  Issue Date: August 1998)
63  *
64  *	The following test is erm.. interesting. AMD neglected to up
65  *	the chip setting when fixing the bug but they also tweaked some
66  *	performance at the same time..
67  */
68 
69 extern void vide(void);
70 __asm__(".align 4\nvide: ret");
71 
72 static void __cpuinit init_amd_k5(struct cpuinfo_x86 *c)
73 {
74 /*
75  * General Systems BIOSen alias the cpu frequency registers
76  * of the Elan at 0x000df000. Unfortuantly, one of the Linux
77  * drivers subsequently pokes it, and changes the CPU speed.
78  * Workaround : Remove the unneeded alias.
79  */
80 #define CBAR		(0xfffc) /* Configuration Base Address  (32-bit) */
81 #define CBAR_ENB	(0x80000000)
82 #define CBAR_KEY	(0X000000CB)
83 	if (c->x86_model == 9 || c->x86_model == 10) {
84 		if (inl(CBAR) & CBAR_ENB)
85 			outl(0 | CBAR_KEY, CBAR);
86 	}
87 }
88 
89 
90 static void __cpuinit init_amd_k6(struct cpuinfo_x86 *c)
91 {
92 	u32 l, h;
93 	int mbytes = get_num_physpages() >> (20-PAGE_SHIFT);
94 
95 	if (c->x86_model < 6) {
96 		/* Based on AMD doc 20734R - June 2000 */
97 		if (c->x86_model == 0) {
98 			clear_cpu_cap(c, X86_FEATURE_APIC);
99 			set_cpu_cap(c, X86_FEATURE_PGE);
100 		}
101 		return;
102 	}
103 
104 	if (c->x86_model == 6 && c->x86_mask == 1) {
105 		const int K6_BUG_LOOP = 1000000;
106 		int n;
107 		void (*f_vide)(void);
108 		unsigned long d, d2;
109 
110 		printk(KERN_INFO "AMD K6 stepping B detected - ");
111 
112 		/*
113 		 * It looks like AMD fixed the 2.6.2 bug and improved indirect
114 		 * calls at the same time.
115 		 */
116 
117 		n = K6_BUG_LOOP;
118 		f_vide = vide;
119 		rdtscl(d);
120 		while (n--)
121 			f_vide();
122 		rdtscl(d2);
123 		d = d2-d;
124 
125 		if (d > 20*K6_BUG_LOOP)
126 			printk(KERN_CONT
127 				"system stability may be impaired when more than 32 MB are used.\n");
128 		else
129 			printk(KERN_CONT "probably OK (after B9730xxxx).\n");
130 	}
131 
132 	/* K6 with old style WHCR */
133 	if (c->x86_model < 8 ||
134 	   (c->x86_model == 8 && c->x86_mask < 8)) {
135 		/* We can only write allocate on the low 508Mb */
136 		if (mbytes > 508)
137 			mbytes = 508;
138 
139 		rdmsr(MSR_K6_WHCR, l, h);
140 		if ((l&0x0000FFFF) == 0) {
141 			unsigned long flags;
142 			l = (1<<0)|((mbytes/4)<<1);
143 			local_irq_save(flags);
144 			wbinvd();
145 			wrmsr(MSR_K6_WHCR, l, h);
146 			local_irq_restore(flags);
147 			printk(KERN_INFO "Enabling old style K6 write allocation for %d Mb\n",
148 				mbytes);
149 		}
150 		return;
151 	}
152 
153 	if ((c->x86_model == 8 && c->x86_mask > 7) ||
154 	     c->x86_model == 9 || c->x86_model == 13) {
155 		/* The more serious chips .. */
156 
157 		if (mbytes > 4092)
158 			mbytes = 4092;
159 
160 		rdmsr(MSR_K6_WHCR, l, h);
161 		if ((l&0xFFFF0000) == 0) {
162 			unsigned long flags;
163 			l = ((mbytes>>2)<<22)|(1<<16);
164 			local_irq_save(flags);
165 			wbinvd();
166 			wrmsr(MSR_K6_WHCR, l, h);
167 			local_irq_restore(flags);
168 			printk(KERN_INFO "Enabling new style K6 write allocation for %d Mb\n",
169 				mbytes);
170 		}
171 
172 		return;
173 	}
174 
175 	if (c->x86_model == 10) {
176 		/* AMD Geode LX is model 10 */
177 		/* placeholder for any needed mods */
178 		return;
179 	}
180 }
181 
182 static void __cpuinit amd_k7_smp_check(struct cpuinfo_x86 *c)
183 {
184 	/* calling is from identify_secondary_cpu() ? */
185 	if (!c->cpu_index)
186 		return;
187 
188 	/*
189 	 * Certain Athlons might work (for various values of 'work') in SMP
190 	 * but they are not certified as MP capable.
191 	 */
192 	/* Athlon 660/661 is valid. */
193 	if ((c->x86_model == 6) && ((c->x86_mask == 0) ||
194 	    (c->x86_mask == 1)))
195 		return;
196 
197 	/* Duron 670 is valid */
198 	if ((c->x86_model == 7) && (c->x86_mask == 0))
199 		return;
200 
201 	/*
202 	 * Athlon 662, Duron 671, and Athlon >model 7 have capability
203 	 * bit. It's worth noting that the A5 stepping (662) of some
204 	 * Athlon XP's have the MP bit set.
205 	 * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for
206 	 * more.
207 	 */
208 	if (((c->x86_model == 6) && (c->x86_mask >= 2)) ||
209 	    ((c->x86_model == 7) && (c->x86_mask >= 1)) ||
210 	     (c->x86_model > 7))
211 		if (cpu_has_mp)
212 			return;
213 
214 	/* If we get here, not a certified SMP capable AMD system. */
215 
216 	/*
217 	 * Don't taint if we are running SMP kernel on a single non-MP
218 	 * approved Athlon
219 	 */
220 	WARN_ONCE(1, "WARNING: This combination of AMD"
221 		" processors is not suitable for SMP.\n");
222 	add_taint(TAINT_UNSAFE_SMP, LOCKDEP_NOW_UNRELIABLE);
223 }
224 
225 static void __cpuinit init_amd_k7(struct cpuinfo_x86 *c)
226 {
227 	u32 l, h;
228 
229 	/*
230 	 * Bit 15 of Athlon specific MSR 15, needs to be 0
231 	 * to enable SSE on Palomino/Morgan/Barton CPU's.
232 	 * If the BIOS didn't enable it already, enable it here.
233 	 */
234 	if (c->x86_model >= 6 && c->x86_model <= 10) {
235 		if (!cpu_has(c, X86_FEATURE_XMM)) {
236 			printk(KERN_INFO "Enabling disabled K7/SSE Support.\n");
237 			rdmsr(MSR_K7_HWCR, l, h);
238 			l &= ~0x00008000;
239 			wrmsr(MSR_K7_HWCR, l, h);
240 			set_cpu_cap(c, X86_FEATURE_XMM);
241 		}
242 	}
243 
244 	/*
245 	 * It's been determined by AMD that Athlons since model 8 stepping 1
246 	 * are more robust with CLK_CTL set to 200xxxxx instead of 600xxxxx
247 	 * As per AMD technical note 27212 0.2
248 	 */
249 	if ((c->x86_model == 8 && c->x86_mask >= 1) || (c->x86_model > 8)) {
250 		rdmsr(MSR_K7_CLK_CTL, l, h);
251 		if ((l & 0xfff00000) != 0x20000000) {
252 			printk(KERN_INFO
253 			    "CPU: CLK_CTL MSR was %x. Reprogramming to %x\n",
254 					l, ((l & 0x000fffff)|0x20000000));
255 			wrmsr(MSR_K7_CLK_CTL, (l & 0x000fffff)|0x20000000, h);
256 		}
257 	}
258 
259 	set_cpu_cap(c, X86_FEATURE_K7);
260 
261 	amd_k7_smp_check(c);
262 }
263 #endif
264 
265 #ifdef CONFIG_NUMA
266 /*
267  * To workaround broken NUMA config.  Read the comment in
268  * srat_detect_node().
269  */
270 static int __cpuinit nearby_node(int apicid)
271 {
272 	int i, node;
273 
274 	for (i = apicid - 1; i >= 0; i--) {
275 		node = __apicid_to_node[i];
276 		if (node != NUMA_NO_NODE && node_online(node))
277 			return node;
278 	}
279 	for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
280 		node = __apicid_to_node[i];
281 		if (node != NUMA_NO_NODE && node_online(node))
282 			return node;
283 	}
284 	return first_node(node_online_map); /* Shouldn't happen */
285 }
286 #endif
287 
288 /*
289  * Fixup core topology information for
290  * (1) AMD multi-node processors
291  *     Assumption: Number of cores in each internal node is the same.
292  * (2) AMD processors supporting compute units
293  */
294 #ifdef CONFIG_X86_HT
295 static void __cpuinit amd_get_topology(struct cpuinfo_x86 *c)
296 {
297 	u32 nodes, cores_per_cu = 1;
298 	u8 node_id;
299 	int cpu = smp_processor_id();
300 
301 	/* get information required for multi-node processors */
302 	if (cpu_has_topoext) {
303 		u32 eax, ebx, ecx, edx;
304 
305 		cpuid(0x8000001e, &eax, &ebx, &ecx, &edx);
306 		nodes = ((ecx >> 8) & 7) + 1;
307 		node_id = ecx & 7;
308 
309 		/* get compute unit information */
310 		smp_num_siblings = ((ebx >> 8) & 3) + 1;
311 		c->compute_unit_id = ebx & 0xff;
312 		cores_per_cu += ((ebx >> 8) & 3);
313 	} else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) {
314 		u64 value;
315 
316 		rdmsrl(MSR_FAM10H_NODE_ID, value);
317 		nodes = ((value >> 3) & 7) + 1;
318 		node_id = value & 7;
319 	} else
320 		return;
321 
322 	/* fixup multi-node processor information */
323 	if (nodes > 1) {
324 		u32 cores_per_node;
325 		u32 cus_per_node;
326 
327 		set_cpu_cap(c, X86_FEATURE_AMD_DCM);
328 		cores_per_node = c->x86_max_cores / nodes;
329 		cus_per_node = cores_per_node / cores_per_cu;
330 
331 		/* store NodeID, use llc_shared_map to store sibling info */
332 		per_cpu(cpu_llc_id, cpu) = node_id;
333 
334 		/* core id has to be in the [0 .. cores_per_node - 1] range */
335 		c->cpu_core_id %= cores_per_node;
336 		c->compute_unit_id %= cus_per_node;
337 	}
338 }
339 #endif
340 
341 /*
342  * On a AMD dual core setup the lower bits of the APIC id distingush the cores.
343  * Assumes number of cores is a power of two.
344  */
345 static void __cpuinit amd_detect_cmp(struct cpuinfo_x86 *c)
346 {
347 #ifdef CONFIG_X86_HT
348 	unsigned bits;
349 	int cpu = smp_processor_id();
350 
351 	bits = c->x86_coreid_bits;
352 	/* Low order bits define the core id (index of core in socket) */
353 	c->cpu_core_id = c->initial_apicid & ((1 << bits)-1);
354 	/* Convert the initial APIC ID into the socket ID */
355 	c->phys_proc_id = c->initial_apicid >> bits;
356 	/* use socket ID also for last level cache */
357 	per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
358 	amd_get_topology(c);
359 #endif
360 }
361 
362 u16 amd_get_nb_id(int cpu)
363 {
364 	u16 id = 0;
365 #ifdef CONFIG_SMP
366 	id = per_cpu(cpu_llc_id, cpu);
367 #endif
368 	return id;
369 }
370 EXPORT_SYMBOL_GPL(amd_get_nb_id);
371 
372 static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
373 {
374 #ifdef CONFIG_NUMA
375 	int cpu = smp_processor_id();
376 	int node;
377 	unsigned apicid = c->apicid;
378 
379 	node = numa_cpu_node(cpu);
380 	if (node == NUMA_NO_NODE)
381 		node = per_cpu(cpu_llc_id, cpu);
382 
383 	/*
384 	 * On multi-fabric platform (e.g. Numascale NumaChip) a
385 	 * platform-specific handler needs to be called to fixup some
386 	 * IDs of the CPU.
387 	 */
388 	if (x86_cpuinit.fixup_cpu_id)
389 		x86_cpuinit.fixup_cpu_id(c, node);
390 
391 	if (!node_online(node)) {
392 		/*
393 		 * Two possibilities here:
394 		 *
395 		 * - The CPU is missing memory and no node was created.  In
396 		 *   that case try picking one from a nearby CPU.
397 		 *
398 		 * - The APIC IDs differ from the HyperTransport node IDs
399 		 *   which the K8 northbridge parsing fills in.  Assume
400 		 *   they are all increased by a constant offset, but in
401 		 *   the same order as the HT nodeids.  If that doesn't
402 		 *   result in a usable node fall back to the path for the
403 		 *   previous case.
404 		 *
405 		 * This workaround operates directly on the mapping between
406 		 * APIC ID and NUMA node, assuming certain relationship
407 		 * between APIC ID, HT node ID and NUMA topology.  As going
408 		 * through CPU mapping may alter the outcome, directly
409 		 * access __apicid_to_node[].
410 		 */
411 		int ht_nodeid = c->initial_apicid;
412 
413 		if (ht_nodeid >= 0 &&
414 		    __apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
415 			node = __apicid_to_node[ht_nodeid];
416 		/* Pick a nearby node */
417 		if (!node_online(node))
418 			node = nearby_node(apicid);
419 	}
420 	numa_set_node(cpu, node);
421 #endif
422 }
423 
424 static void __cpuinit early_init_amd_mc(struct cpuinfo_x86 *c)
425 {
426 #ifdef CONFIG_X86_HT
427 	unsigned bits, ecx;
428 
429 	/* Multi core CPU? */
430 	if (c->extended_cpuid_level < 0x80000008)
431 		return;
432 
433 	ecx = cpuid_ecx(0x80000008);
434 
435 	c->x86_max_cores = (ecx & 0xff) + 1;
436 
437 	/* CPU telling us the core id bits shift? */
438 	bits = (ecx >> 12) & 0xF;
439 
440 	/* Otherwise recompute */
441 	if (bits == 0) {
442 		while ((1 << bits) < c->x86_max_cores)
443 			bits++;
444 	}
445 
446 	c->x86_coreid_bits = bits;
447 #endif
448 }
449 
450 static void __cpuinit bsp_init_amd(struct cpuinfo_x86 *c)
451 {
452 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
453 
454 		if (c->x86 > 0x10 ||
455 		    (c->x86 == 0x10 && c->x86_model >= 0x2)) {
456 			u64 val;
457 
458 			rdmsrl(MSR_K7_HWCR, val);
459 			if (!(val & BIT(24)))
460 				printk(KERN_WARNING FW_BUG "TSC doesn't count "
461 					"with P0 frequency!\n");
462 		}
463 	}
464 
465 	if (c->x86 == 0x15) {
466 		unsigned long upperbit;
467 		u32 cpuid, assoc;
468 
469 		cpuid	 = cpuid_edx(0x80000005);
470 		assoc	 = cpuid >> 16 & 0xff;
471 		upperbit = ((cpuid >> 24) << 10) / assoc;
472 
473 		va_align.mask	  = (upperbit - 1) & PAGE_MASK;
474 		va_align.flags    = ALIGN_VA_32 | ALIGN_VA_64;
475 	}
476 }
477 
478 static void __cpuinit early_init_amd(struct cpuinfo_x86 *c)
479 {
480 	early_init_amd_mc(c);
481 
482 	/*
483 	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
484 	 * with P/T states and does not stop in deep C-states
485 	 */
486 	if (c->x86_power & (1 << 8)) {
487 		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
488 		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
489 		if (!check_tsc_unstable())
490 			sched_clock_stable = 1;
491 	}
492 
493 #ifdef CONFIG_X86_64
494 	set_cpu_cap(c, X86_FEATURE_SYSCALL32);
495 #else
496 	/*  Set MTRR capability flag if appropriate */
497 	if (c->x86 == 5)
498 		if (c->x86_model == 13 || c->x86_model == 9 ||
499 		    (c->x86_model == 8 && c->x86_mask >= 8))
500 			set_cpu_cap(c, X86_FEATURE_K6_MTRR);
501 #endif
502 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI)
503 	/* check CPU config space for extended APIC ID */
504 	if (cpu_has_apic && c->x86 >= 0xf) {
505 		unsigned int val;
506 		val = read_pci_config(0, 24, 0, 0x68);
507 		if ((val & ((1 << 17) | (1 << 18))) == ((1 << 17) | (1 << 18)))
508 			set_cpu_cap(c, X86_FEATURE_EXTD_APICID);
509 	}
510 #endif
511 }
512 
513 static const int amd_erratum_383[];
514 static const int amd_erratum_400[];
515 static bool cpu_has_amd_erratum(const int *erratum);
516 
517 static void __cpuinit init_amd(struct cpuinfo_x86 *c)
518 {
519 	u32 dummy;
520 	unsigned long long value;
521 
522 #ifdef CONFIG_SMP
523 	/*
524 	 * Disable TLB flush filter by setting HWCR.FFDIS on K8
525 	 * bit 6 of msr C001_0015
526 	 *
527 	 * Errata 63 for SH-B3 steppings
528 	 * Errata 122 for all steppings (F+ have it disabled by default)
529 	 */
530 	if (c->x86 == 0xf) {
531 		rdmsrl(MSR_K7_HWCR, value);
532 		value |= 1 << 6;
533 		wrmsrl(MSR_K7_HWCR, value);
534 	}
535 #endif
536 
537 	early_init_amd(c);
538 
539 	/*
540 	 * Bit 31 in normal CPUID used for nonstandard 3DNow ID;
541 	 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway
542 	 */
543 	clear_cpu_cap(c, 0*32+31);
544 
545 #ifdef CONFIG_X86_64
546 	/* On C+ stepping K8 rep microcode works well for copy/memset */
547 	if (c->x86 == 0xf) {
548 		u32 level;
549 
550 		level = cpuid_eax(1);
551 		if ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58)
552 			set_cpu_cap(c, X86_FEATURE_REP_GOOD);
553 
554 		/*
555 		 * Some BIOSes incorrectly force this feature, but only K8
556 		 * revision D (model = 0x14) and later actually support it.
557 		 * (AMD Erratum #110, docId: 25759).
558 		 */
559 		if (c->x86_model < 0x14 && cpu_has(c, X86_FEATURE_LAHF_LM)) {
560 			clear_cpu_cap(c, X86_FEATURE_LAHF_LM);
561 			if (!rdmsrl_amd_safe(0xc001100d, &value)) {
562 				value &= ~(1ULL << 32);
563 				wrmsrl_amd_safe(0xc001100d, value);
564 			}
565 		}
566 
567 	}
568 	if (c->x86 >= 0x10)
569 		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
570 
571 	/* get apicid instead of initial apic id from cpuid */
572 	c->apicid = hard_smp_processor_id();
573 #else
574 
575 	/*
576 	 *	FIXME: We should handle the K5 here. Set up the write
577 	 *	range and also turn on MSR 83 bits 4 and 31 (write alloc,
578 	 *	no bus pipeline)
579 	 */
580 
581 	switch (c->x86) {
582 	case 4:
583 		init_amd_k5(c);
584 		break;
585 	case 5:
586 		init_amd_k6(c);
587 		break;
588 	case 6: /* An Athlon/Duron */
589 		init_amd_k7(c);
590 		break;
591 	}
592 
593 	/* K6s reports MCEs but don't actually have all the MSRs */
594 	if (c->x86 < 6)
595 		clear_cpu_cap(c, X86_FEATURE_MCE);
596 #endif
597 
598 	/* Enable workaround for FXSAVE leak */
599 	if (c->x86 >= 6)
600 		set_cpu_cap(c, X86_FEATURE_FXSAVE_LEAK);
601 
602 	if (!c->x86_model_id[0]) {
603 		switch (c->x86) {
604 		case 0xf:
605 			/* Should distinguish Models here, but this is only
606 			   a fallback anyways. */
607 			strcpy(c->x86_model_id, "Hammer");
608 			break;
609 		}
610 	}
611 
612 	/* re-enable TopologyExtensions if switched off by BIOS */
613 	if ((c->x86 == 0x15) &&
614 	    (c->x86_model >= 0x10) && (c->x86_model <= 0x1f) &&
615 	    !cpu_has(c, X86_FEATURE_TOPOEXT)) {
616 
617 		if (!rdmsrl_safe(0xc0011005, &value)) {
618 			value |= 1ULL << 54;
619 			wrmsrl_safe(0xc0011005, value);
620 			rdmsrl(0xc0011005, value);
621 			if (value & (1ULL << 54)) {
622 				set_cpu_cap(c, X86_FEATURE_TOPOEXT);
623 				printk(KERN_INFO FW_INFO "CPU: Re-enabling "
624 				  "disabled Topology Extensions Support\n");
625 			}
626 		}
627 	}
628 
629 	/*
630 	 * The way access filter has a performance penalty on some workloads.
631 	 * Disable it on the affected CPUs.
632 	 */
633 	if ((c->x86 == 0x15) &&
634 	    (c->x86_model >= 0x02) && (c->x86_model < 0x20)) {
635 
636 		if (!rdmsrl_safe(0xc0011021, &value) && !(value & 0x1E)) {
637 			value |= 0x1E;
638 			wrmsrl_safe(0xc0011021, value);
639 		}
640 	}
641 
642 	cpu_detect_cache_sizes(c);
643 
644 	/* Multi core CPU? */
645 	if (c->extended_cpuid_level >= 0x80000008) {
646 		amd_detect_cmp(c);
647 		srat_detect_node(c);
648 	}
649 
650 #ifdef CONFIG_X86_32
651 	detect_ht(c);
652 #endif
653 
654 	init_amd_cacheinfo(c);
655 
656 	if (c->x86 >= 0xf)
657 		set_cpu_cap(c, X86_FEATURE_K8);
658 
659 	if (cpu_has_xmm2) {
660 		/* MFENCE stops RDTSC speculation */
661 		set_cpu_cap(c, X86_FEATURE_MFENCE_RDTSC);
662 	}
663 
664 #ifdef CONFIG_X86_64
665 	if (c->x86 == 0x10) {
666 		/* do this for boot cpu */
667 		if (c == &boot_cpu_data)
668 			check_enable_amd_mmconf_dmi();
669 
670 		fam10h_check_enable_mmcfg();
671 	}
672 
673 	if (c == &boot_cpu_data && c->x86 >= 0xf) {
674 		unsigned long long tseg;
675 
676 		/*
677 		 * Split up direct mapping around the TSEG SMM area.
678 		 * Don't do it for gbpages because there seems very little
679 		 * benefit in doing so.
680 		 */
681 		if (!rdmsrl_safe(MSR_K8_TSEG_ADDR, &tseg)) {
682 			unsigned long pfn = tseg >> PAGE_SHIFT;
683 
684 			printk(KERN_DEBUG "tseg: %010llx\n", tseg);
685 			if (pfn_range_is_mapped(pfn, pfn + 1))
686 				set_memory_4k((unsigned long)__va(tseg), 1);
687 		}
688 	}
689 #endif
690 
691 	/*
692 	 * Family 0x12 and above processors have APIC timer
693 	 * running in deep C states.
694 	 */
695 	if (c->x86 > 0x11)
696 		set_cpu_cap(c, X86_FEATURE_ARAT);
697 
698 	if (c->x86 == 0x10) {
699 		/*
700 		 * Disable GART TLB Walk Errors on Fam10h. We do this here
701 		 * because this is always needed when GART is enabled, even in a
702 		 * kernel which has no MCE support built in.
703 		 * BIOS should disable GartTlbWlk Errors themself. If
704 		 * it doesn't do it here as suggested by the BKDG.
705 		 *
706 		 * Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=33012
707 		 */
708 		u64 mask;
709 		int err;
710 
711 		err = rdmsrl_safe(MSR_AMD64_MCx_MASK(4), &mask);
712 		if (err == 0) {
713 			mask |= (1 << 10);
714 			wrmsrl_safe(MSR_AMD64_MCx_MASK(4), mask);
715 		}
716 
717 		/*
718 		 * On family 10h BIOS may not have properly enabled WC+ support,
719 		 * causing it to be converted to CD memtype. This may result in
720 		 * performance degradation for certain nested-paging guests.
721 		 * Prevent this conversion by clearing bit 24 in
722 		 * MSR_AMD64_BU_CFG2.
723 		 *
724 		 * NOTE: we want to use the _safe accessors so as not to #GP kvm
725 		 * guests on older kvm hosts.
726 		 */
727 
728 		rdmsrl_safe(MSR_AMD64_BU_CFG2, &value);
729 		value &= ~(1ULL << 24);
730 		wrmsrl_safe(MSR_AMD64_BU_CFG2, value);
731 
732 		if (cpu_has_amd_erratum(amd_erratum_383))
733 			set_cpu_bug(c, X86_BUG_AMD_TLB_MMATCH);
734 	}
735 
736 	if (cpu_has_amd_erratum(amd_erratum_400))
737 		set_cpu_bug(c, X86_BUG_AMD_APIC_C1E);
738 
739 	rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy);
740 }
741 
742 #ifdef CONFIG_X86_32
743 static unsigned int __cpuinit amd_size_cache(struct cpuinfo_x86 *c,
744 							unsigned int size)
745 {
746 	/* AMD errata T13 (order #21922) */
747 	if ((c->x86 == 6)) {
748 		/* Duron Rev A0 */
749 		if (c->x86_model == 3 && c->x86_mask == 0)
750 			size = 64;
751 		/* Tbird rev A1/A2 */
752 		if (c->x86_model == 4 &&
753 			(c->x86_mask == 0 || c->x86_mask == 1))
754 			size = 256;
755 	}
756 	return size;
757 }
758 #endif
759 
760 static void __cpuinit cpu_set_tlb_flushall_shift(struct cpuinfo_x86 *c)
761 {
762 	tlb_flushall_shift = 5;
763 
764 	if (c->x86 <= 0x11)
765 		tlb_flushall_shift = 4;
766 }
767 
768 static void __cpuinit cpu_detect_tlb_amd(struct cpuinfo_x86 *c)
769 {
770 	u32 ebx, eax, ecx, edx;
771 	u16 mask = 0xfff;
772 
773 	if (c->x86 < 0xf)
774 		return;
775 
776 	if (c->extended_cpuid_level < 0x80000006)
777 		return;
778 
779 	cpuid(0x80000006, &eax, &ebx, &ecx, &edx);
780 
781 	tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask;
782 	tlb_lli_4k[ENTRIES] = ebx & mask;
783 
784 	/*
785 	 * K8 doesn't have 2M/4M entries in the L2 TLB so read out the L1 TLB
786 	 * characteristics from the CPUID function 0x80000005 instead.
787 	 */
788 	if (c->x86 == 0xf) {
789 		cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
790 		mask = 0xff;
791 	}
792 
793 	/* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
794 	if (!((eax >> 16) & mask)) {
795 		u32 a, b, c, d;
796 
797 		cpuid(0x80000005, &a, &b, &c, &d);
798 		tlb_lld_2m[ENTRIES] = (a >> 16) & 0xff;
799 	} else {
800 		tlb_lld_2m[ENTRIES] = (eax >> 16) & mask;
801 	}
802 
803 	/* a 4M entry uses two 2M entries */
804 	tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1;
805 
806 	/* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */
807 	if (!(eax & mask)) {
808 		/* Erratum 658 */
809 		if (c->x86 == 0x15 && c->x86_model <= 0x1f) {
810 			tlb_lli_2m[ENTRIES] = 1024;
811 		} else {
812 			cpuid(0x80000005, &eax, &ebx, &ecx, &edx);
813 			tlb_lli_2m[ENTRIES] = eax & 0xff;
814 		}
815 	} else
816 		tlb_lli_2m[ENTRIES] = eax & mask;
817 
818 	tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1;
819 
820 	cpu_set_tlb_flushall_shift(c);
821 }
822 
823 static const struct cpu_dev __cpuinitconst amd_cpu_dev = {
824 	.c_vendor	= "AMD",
825 	.c_ident	= { "AuthenticAMD" },
826 #ifdef CONFIG_X86_32
827 	.c_models = {
828 		{ .vendor = X86_VENDOR_AMD, .family = 4, .model_names =
829 		  {
830 			  [3] = "486 DX/2",
831 			  [7] = "486 DX/2-WB",
832 			  [8] = "486 DX/4",
833 			  [9] = "486 DX/4-WB",
834 			  [14] = "Am5x86-WT",
835 			  [15] = "Am5x86-WB"
836 		  }
837 		},
838 	},
839 	.c_size_cache	= amd_size_cache,
840 #endif
841 	.c_early_init   = early_init_amd,
842 	.c_detect_tlb	= cpu_detect_tlb_amd,
843 	.c_bsp_init	= bsp_init_amd,
844 	.c_init		= init_amd,
845 	.c_x86_vendor	= X86_VENDOR_AMD,
846 };
847 
848 cpu_dev_register(amd_cpu_dev);
849 
850 /*
851  * AMD errata checking
852  *
853  * Errata are defined as arrays of ints using the AMD_LEGACY_ERRATUM() or
854  * AMD_OSVW_ERRATUM() macros. The latter is intended for newer errata that
855  * have an OSVW id assigned, which it takes as first argument. Both take a
856  * variable number of family-specific model-stepping ranges created by
857  * AMD_MODEL_RANGE().
858  *
859  * Example:
860  *
861  * const int amd_erratum_319[] =
862  *	AMD_LEGACY_ERRATUM(AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0x4, 0x2),
863  *			   AMD_MODEL_RANGE(0x10, 0x8, 0x0, 0x8, 0x0),
864  *			   AMD_MODEL_RANGE(0x10, 0x9, 0x0, 0x9, 0x0));
865  */
866 
867 #define AMD_LEGACY_ERRATUM(...)		{ -1, __VA_ARGS__, 0 }
868 #define AMD_OSVW_ERRATUM(osvw_id, ...)	{ osvw_id, __VA_ARGS__, 0 }
869 #define AMD_MODEL_RANGE(f, m_start, s_start, m_end, s_end) \
870 	((f << 24) | (m_start << 16) | (s_start << 12) | (m_end << 4) | (s_end))
871 #define AMD_MODEL_RANGE_FAMILY(range)	(((range) >> 24) & 0xff)
872 #define AMD_MODEL_RANGE_START(range)	(((range) >> 12) & 0xfff)
873 #define AMD_MODEL_RANGE_END(range)	((range) & 0xfff)
874 
875 static const int amd_erratum_400[] =
876 	AMD_OSVW_ERRATUM(1, AMD_MODEL_RANGE(0xf, 0x41, 0x2, 0xff, 0xf),
877 			    AMD_MODEL_RANGE(0x10, 0x2, 0x1, 0xff, 0xf));
878 
879 static const int amd_erratum_383[] =
880 	AMD_OSVW_ERRATUM(3, AMD_MODEL_RANGE(0x10, 0, 0, 0xff, 0xf));
881 
882 static bool cpu_has_amd_erratum(const int *erratum)
883 {
884 	struct cpuinfo_x86 *cpu = __this_cpu_ptr(&cpu_info);
885 	int osvw_id = *erratum++;
886 	u32 range;
887 	u32 ms;
888 
889 	/*
890 	 * If called early enough that current_cpu_data hasn't been initialized
891 	 * yet, fall back to boot_cpu_data.
892 	 */
893 	if (cpu->x86 == 0)
894 		cpu = &boot_cpu_data;
895 
896 	if (cpu->x86_vendor != X86_VENDOR_AMD)
897 		return false;
898 
899 	if (osvw_id >= 0 && osvw_id < 65536 &&
900 	    cpu_has(cpu, X86_FEATURE_OSVW)) {
901 		u64 osvw_len;
902 
903 		rdmsrl(MSR_AMD64_OSVW_ID_LENGTH, osvw_len);
904 		if (osvw_id < osvw_len) {
905 			u64 osvw_bits;
906 
907 			rdmsrl(MSR_AMD64_OSVW_STATUS + (osvw_id >> 6),
908 			    osvw_bits);
909 			return osvw_bits & (1ULL << (osvw_id & 0x3f));
910 		}
911 	}
912 
913 	/* OSVW unavailable or ID unknown, match family-model-stepping range */
914 	ms = (cpu->x86_model << 4) | cpu->x86_mask;
915 	while ((range = *erratum++))
916 		if ((cpu->x86 == AMD_MODEL_RANGE_FAMILY(range)) &&
917 		    (ms >= AMD_MODEL_RANGE_START(range)) &&
918 		    (ms <= AMD_MODEL_RANGE_END(range)))
919 			return true;
920 
921 	return false;
922 }
923