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v3.5.6
  1#include <linux/init.h>
  2#include <linux/kernel.h>
 
  3
  4#include <linux/string.h>
  5#include <linux/bitops.h>
  6#include <linux/smp.h>
  7#include <linux/sched.h>
 
  8#include <linux/thread_info.h>
  9#include <linux/module.h>
 10#include <linux/uaccess.h>
 11
 12#include <asm/processor.h>
 13#include <asm/pgtable.h>
 14#include <asm/msr.h>
 15#include <asm/bugs.h>
 16#include <asm/cpu.h>
 
 
 
 
 
 
 
 
 
 17
 18#ifdef CONFIG_X86_64
 19#include <linux/topology.h>
 20#include <asm/numa_64.h>
 21#endif
 22
 23#include "cpu.h"
 24
 25#ifdef CONFIG_X86_LOCAL_APIC
 26#include <asm/mpspec.h>
 27#include <asm/apic.h>
 28#endif
 29
 30static void __cpuinit early_init_intel(struct cpuinfo_x86 *c)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 31{
 32	u64 misc_enable;
 33
 34	/* Unmask CPUID levels if masked: */
 35	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
 36		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
 37
 38		if (misc_enable & MSR_IA32_MISC_ENABLE_LIMIT_CPUID) {
 39			misc_enable &= ~MSR_IA32_MISC_ENABLE_LIMIT_CPUID;
 40			wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
 41			c->cpuid_level = cpuid_eax(0);
 42			get_cpu_cap(c);
 43		}
 44	}
 45
 46	if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
 47		(c->x86 == 0x6 && c->x86_model >= 0x0e))
 48		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 49
 50	if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64)) {
 51		unsigned lower_word;
 52
 53		wrmsr(MSR_IA32_UCODE_REV, 0, 0);
 54		/* Required by the SDM */
 55		sync_core();
 56		rdmsr(MSR_IA32_UCODE_REV, lower_word, c->microcode);
 
 
 
 
 
 
 
 
 
 
 57	}
 58
 59	/*
 60	 * Atom erratum AAE44/AAF40/AAG38/AAH41:
 61	 *
 62	 * A race condition between speculative fetches and invalidating
 63	 * a large page.  This is worked around in microcode, but we
 64	 * need the microcode to have already been loaded... so if it is
 65	 * not, recommend a BIOS update and disable large pages.
 66	 */
 67	if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_mask <= 2 &&
 68	    c->microcode < 0x20e) {
 69		printk(KERN_WARNING "Atom PSE erratum detected, BIOS microcode update recommended\n");
 70		clear_cpu_cap(c, X86_FEATURE_PSE);
 71	}
 72
 73#ifdef CONFIG_X86_64
 74	set_cpu_cap(c, X86_FEATURE_SYSENTER32);
 75#else
 76	/* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
 77	if (c->x86 == 15 && c->x86_cache_alignment == 64)
 78		c->x86_cache_alignment = 128;
 79#endif
 80
 81	/* CPUID workaround for 0F33/0F34 CPU */
 82	if (c->x86 == 0xF && c->x86_model == 0x3
 83	    && (c->x86_mask == 0x3 || c->x86_mask == 0x4))
 84		c->x86_phys_bits = 36;
 85
 86	/*
 87	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
 88	 * with P/T states and does not stop in deep C-states.
 89	 *
 90	 * It is also reliable across cores and sockets. (but not across
 91	 * cabinets - we turn it off in that case explicitly.)
 92	 */
 93	if (c->x86_power & (1 << 8)) {
 94		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 95		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
 96		if (!check_tsc_unstable())
 97			sched_clock_stable = 1;
 
 
 
 
 
 
 
 
 
 
 
 
 98	}
 99
100	/*
101	 * There is a known erratum on Pentium III and Core Solo
102	 * and Core Duo CPUs.
103	 * " Page with PAT set to WC while associated MTRR is UC
104	 *   may consolidate to UC "
105	 * Because of this erratum, it is better to stick with
106	 * setting WC in MTRR rather than using PAT on these CPUs.
107	 *
108	 * Enable PAT WC only on P4, Core 2 or later CPUs.
109	 */
110	if (c->x86 == 6 && c->x86_model < 15)
111		clear_cpu_cap(c, X86_FEATURE_PAT);
112
113#ifdef CONFIG_KMEMCHECK
114	/*
115	 * P4s have a "fast strings" feature which causes single-
116	 * stepping REP instructions to only generate a #DB on
117	 * cache-line boundaries.
118	 *
119	 * Ingo Molnar reported a Pentium D (model 6) and a Xeon
120	 * (model 2) with the same problem.
121	 */
122	if (c->x86 == 15) {
123		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
124
125		if (misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING) {
126			printk(KERN_INFO "kmemcheck: Disabling fast string operations\n");
127
128			misc_enable &= ~MSR_IA32_MISC_ENABLE_FAST_STRING;
129			wrmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
130		}
131	}
132#endif
133
134	/*
135	 * If fast string is not enabled in IA32_MISC_ENABLE for any reason,
136	 * clear the fast string and enhanced fast string CPU capabilities.
137	 */
138	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
139		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
140		if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
141			printk(KERN_INFO "Disabled fast string operations\n");
142			setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
143			setup_clear_cpu_cap(X86_FEATURE_ERMS);
144		}
145	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
146}
147
148#ifdef CONFIG_X86_32
149/*
150 *	Early probe support logic for ppro memory erratum #50
151 *
152 *	This is called before we do cpu ident work
153 */
154
155int __cpuinit ppro_with_ram_bug(void)
156{
157	/* Uses data from early_cpu_detect now */
158	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
159	    boot_cpu_data.x86 == 6 &&
160	    boot_cpu_data.x86_model == 1 &&
161	    boot_cpu_data.x86_mask < 8) {
162		printk(KERN_INFO "Pentium Pro with Errata#50 detected. Taking evasive action.\n");
163		return 1;
164	}
165	return 0;
166}
167
168#ifdef CONFIG_X86_F00F_BUG
169static void __cpuinit trap_init_f00f_bug(void)
170{
171	__set_fixmap(FIX_F00F_IDT, __pa(&idt_table), PAGE_KERNEL_RO);
172
173	/*
174	 * Update the IDT descriptor and reload the IDT so that
175	 * it uses the read-only mapped virtual address.
176	 */
177	idt_descr.address = fix_to_virt(FIX_F00F_IDT);
178	load_idt(&idt_descr);
179}
180#endif
181
182static void __cpuinit intel_smp_check(struct cpuinfo_x86 *c)
183{
184	/* calling is from identify_secondary_cpu() ? */
185	if (!c->cpu_index)
186		return;
187
188	/*
189	 * Mask B, Pentium, but not Pentium MMX
190	 */
191	if (c->x86 == 5 &&
192	    c->x86_mask >= 1 && c->x86_mask <= 4 &&
193	    c->x86_model <= 3) {
194		/*
195		 * Remember we have B step Pentia with bugs
196		 */
197		WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
198				    "with B stepping processors.\n");
199	}
200}
201
202static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
 
203{
204	unsigned long lo, hi;
 
 
 
205
 
 
206#ifdef CONFIG_X86_F00F_BUG
207	/*
208	 * All current models of Pentium and Pentium with MMX technology CPUs
209	 * have the F0 0F bug, which lets nonprivileged users lock up the
210	 * system.
211	 * Note that the workaround only should be initialized once...
212	 */
213	c->f00f_bug = 0;
214	if (!paravirt_enabled() && c->x86 == 5) {
215		static int f00f_workaround_enabled;
216
217		c->f00f_bug = 1;
218		if (!f00f_workaround_enabled) {
219			trap_init_f00f_bug();
220			printk(KERN_NOTICE "Intel Pentium with F0 0F bug - workaround enabled.\n");
221			f00f_workaround_enabled = 1;
222		}
223	}
224#endif
225
226	/*
227	 * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
228	 * model 3 mask 3
229	 */
230	if ((c->x86<<8 | c->x86_model<<4 | c->x86_mask) < 0x633)
231		clear_cpu_cap(c, X86_FEATURE_SEP);
232
233	/*
234	 * P4 Xeon errata 037 workaround.
 
 
 
 
 
 
 
 
 
 
 
235	 * Hardware prefetcher may cause stale data to be loaded into the cache.
236	 */
237	if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_mask == 1)) {
238		rdmsr(MSR_IA32_MISC_ENABLE, lo, hi);
239		if ((lo & MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE) == 0) {
240			printk (KERN_INFO "CPU: C0 stepping P4 Xeon detected.\n");
241			printk (KERN_INFO "CPU: Disabling hardware prefetching (Errata 037)\n");
242			lo |= MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE;
243			wrmsr(MSR_IA32_MISC_ENABLE, lo, hi);
244		}
245	}
246
247	/*
248	 * See if we have a good local APIC by checking for buggy Pentia,
249	 * i.e. all B steppings and the C2 stepping of P54C when using their
250	 * integrated APIC (see 11AP erratum in "Pentium Processor
251	 * Specification Update").
252	 */
253	if (cpu_has_apic && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
254	    (c->x86_mask < 0x6 || c->x86_mask == 0xb))
255		set_cpu_cap(c, X86_FEATURE_11AP);
256
257
258#ifdef CONFIG_X86_INTEL_USERCOPY
259	/*
260	 * Set up the preferred alignment for movsl bulk memory moves
261	 */
262	switch (c->x86) {
263	case 4:		/* 486: untested */
264		break;
265	case 5:		/* Old Pentia: untested */
266		break;
267	case 6:		/* PII/PIII only like movsl with 8-byte alignment */
268		movsl_mask.mask = 7;
269		break;
270	case 15:	/* P4 is OK down to 8-byte alignment */
271		movsl_mask.mask = 7;
272		break;
273	}
274#endif
275
276#ifdef CONFIG_X86_NUMAQ
277	numaq_tsc_disable();
278#endif
279
280	intel_smp_check(c);
281}
282#else
283static void __cpuinit intel_workarounds(struct cpuinfo_x86 *c)
284{
285}
286#endif
287
288static void __cpuinit srat_detect_node(struct cpuinfo_x86 *c)
289{
290#ifdef CONFIG_NUMA
291	unsigned node;
292	int cpu = smp_processor_id();
293
294	/* Don't do the funky fallback heuristics the AMD version employs
295	   for now. */
296	node = numa_cpu_node(cpu);
297	if (node == NUMA_NO_NODE || !node_online(node)) {
298		/* reuse the value from init_cpu_to_node() */
299		node = cpu_to_node(cpu);
300	}
301	numa_set_node(cpu, node);
302#endif
303}
304
305/*
306 * find out the number of processor cores on the die
307 */
308static int __cpuinit intel_num_cpu_cores(struct cpuinfo_x86 *c)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
309{
310	unsigned int eax, ebx, ecx, edx;
 
 
 
 
 
 
 
 
 
 
 
311
312	if (c->cpuid_level < 4)
313		return 1;
 
 
 
314
315	/* Intel has a non-standard dependency on %ecx for this CPUID level. */
316	cpuid_count(4, 0, &eax, &ebx, &ecx, &edx);
317	if (eax & 0x1f)
318		return (eax >> 26) + 1;
319	else
320		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
321}
322
323static void __cpuinit detect_vmx_virtcap(struct cpuinfo_x86 *c)
324{
325	/* Intel VMX MSR indicated features */
326#define X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW	0x00200000
327#define X86_VMX_FEATURE_PROC_CTLS_VNMI		0x00400000
328#define X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS	0x80000000
329#define X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC	0x00000001
330#define X86_VMX_FEATURE_PROC_CTLS2_EPT		0x00000002
331#define X86_VMX_FEATURE_PROC_CTLS2_VPID		0x00000020
332
333	u32 vmx_msr_low, vmx_msr_high, msr_ctl, msr_ctl2;
334
335	clear_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
336	clear_cpu_cap(c, X86_FEATURE_VNMI);
337	clear_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
338	clear_cpu_cap(c, X86_FEATURE_EPT);
339	clear_cpu_cap(c, X86_FEATURE_VPID);
340
341	rdmsr(MSR_IA32_VMX_PROCBASED_CTLS, vmx_msr_low, vmx_msr_high);
342	msr_ctl = vmx_msr_high | vmx_msr_low;
343	if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW)
344		set_cpu_cap(c, X86_FEATURE_TPR_SHADOW);
345	if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_VNMI)
346		set_cpu_cap(c, X86_FEATURE_VNMI);
347	if (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_2ND_CTLS) {
348		rdmsr(MSR_IA32_VMX_PROCBASED_CTLS2,
349		      vmx_msr_low, vmx_msr_high);
350		msr_ctl2 = vmx_msr_high | vmx_msr_low;
351		if ((msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VIRT_APIC) &&
352		    (msr_ctl & X86_VMX_FEATURE_PROC_CTLS_TPR_SHADOW))
353			set_cpu_cap(c, X86_FEATURE_FLEXPRIORITY);
354		if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_EPT)
355			set_cpu_cap(c, X86_FEATURE_EPT);
356		if (msr_ctl2 & X86_VMX_FEATURE_PROC_CTLS2_VPID)
357			set_cpu_cap(c, X86_FEATURE_VPID);
358	}
359}
360
361static void __cpuinit init_intel(struct cpuinfo_x86 *c)
362{
363	unsigned int l2 = 0;
364
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
365	early_init_intel(c);
366
367	intel_workarounds(c);
368
369	/*
370	 * Detect the extended topology information if available. This
371	 * will reinitialise the initial_apicid which will be used
372	 * in init_intel_cacheinfo()
373	 */
374	detect_extended_topology(c);
375
376	l2 = init_intel_cacheinfo(c);
 
 
 
 
 
 
 
 
 
 
 
 
377	if (c->cpuid_level > 9) {
378		unsigned eax = cpuid_eax(10);
379		/* Check for version and the number of counters */
380		if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
381			set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
382	}
383
384	if (cpu_has_xmm2)
385		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
386	if (cpu_has_ds) {
387		unsigned int l1;
 
 
388		rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
389		if (!(l1 & (1<<11)))
390			set_cpu_cap(c, X86_FEATURE_BTS);
391		if (!(l1 & (1<<12)))
392			set_cpu_cap(c, X86_FEATURE_PEBS);
393	}
394
395	if (c->x86 == 6 && c->x86_model == 29 && cpu_has_clflush)
396		set_cpu_cap(c, X86_FEATURE_CLFLUSH_MONITOR);
 
 
 
 
 
397
398#ifdef CONFIG_X86_64
399	if (c->x86 == 15)
400		c->x86_cache_alignment = c->x86_clflush_size * 2;
401	if (c->x86 == 6)
402		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
403#else
404	/*
405	 * Names for the Pentium II/Celeron processors
406	 * detectable only by also checking the cache size.
407	 * Dixon is NOT a Celeron.
408	 */
409	if (c->x86 == 6) {
 
410		char *p = NULL;
411
412		switch (c->x86_model) {
413		case 5:
414			if (l2 == 0)
415				p = "Celeron (Covington)";
416			else if (l2 == 256)
417				p = "Mobile Pentium II (Dixon)";
418			break;
419
420		case 6:
421			if (l2 == 128)
422				p = "Celeron (Mendocino)";
423			else if (c->x86_mask == 0 || c->x86_mask == 5)
424				p = "Celeron-A";
425			break;
426
427		case 8:
428			if (l2 == 128)
429				p = "Celeron (Coppermine)";
430			break;
431		}
432
433		if (p)
434			strcpy(c->x86_model_id, p);
435	}
436
437	if (c->x86 == 15)
438		set_cpu_cap(c, X86_FEATURE_P4);
439	if (c->x86 == 6)
440		set_cpu_cap(c, X86_FEATURE_P3);
441#endif
442
443	if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
444		/*
445		 * let's use the legacy cpuid vector 0x1 and 0x4 for topology
446		 * detection.
447		 */
448		c->x86_max_cores = intel_num_cpu_cores(c);
449#ifdef CONFIG_X86_32
450		detect_ht(c);
451#endif
452	}
453
454	/* Work around errata */
455	srat_detect_node(c);
456
457	if (cpu_has(c, X86_FEATURE_VMX))
458		detect_vmx_virtcap(c);
459
460	/*
461	 * Initialize MSR_IA32_ENERGY_PERF_BIAS if BIOS did not.
462	 * x86_energy_perf_policy(8) is available to change it at run-time
463	 */
464	if (cpu_has(c, X86_FEATURE_EPB)) {
465		u64 epb;
466
467		rdmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
468		if ((epb & 0xF) == ENERGY_PERF_BIAS_PERFORMANCE) {
469			printk_once(KERN_WARNING "ENERGY_PERF_BIAS:"
470				" Set to 'normal', was 'performance'\n"
471				"ENERGY_PERF_BIAS: View and update with"
472				" x86_energy_perf_policy(8)\n");
473			epb = (epb & ~0xF) | ENERGY_PERF_BIAS_NORMAL;
474			wrmsrl(MSR_IA32_ENERGY_PERF_BIAS, epb);
475		}
476	}
477}
478
479#ifdef CONFIG_X86_32
480static unsigned int __cpuinit intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
481{
482	/*
483	 * Intel PIII Tualatin. This comes in two flavours.
484	 * One has 256kb of cache, the other 512. We have no way
485	 * to determine which, so we use a boottime override
486	 * for the 512kb model, and assume 256 otherwise.
487	 */
488	if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
489		size = 256;
 
 
 
 
 
 
 
490	return size;
491}
492#endif
493
494static const struct cpu_dev __cpuinitconst intel_cpu_dev = {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
495	.c_vendor	= "Intel",
496	.c_ident	= { "GenuineIntel" },
497#ifdef CONFIG_X86_32
498	.c_models = {
499		{ .vendor = X86_VENDOR_INTEL, .family = 4, .model_names =
500		  {
501			  [0] = "486 DX-25/33",
502			  [1] = "486 DX-50",
503			  [2] = "486 SX",
504			  [3] = "486 DX/2",
505			  [4] = "486 SL",
506			  [5] = "486 SX/2",
507			  [7] = "486 DX/2-WB",
508			  [8] = "486 DX/4",
509			  [9] = "486 DX/4-WB"
510		  }
511		},
512		{ .vendor = X86_VENDOR_INTEL, .family = 5, .model_names =
513		  {
514			  [0] = "Pentium 60/66 A-step",
515			  [1] = "Pentium 60/66",
516			  [2] = "Pentium 75 - 200",
517			  [3] = "OverDrive PODP5V83",
518			  [4] = "Pentium MMX",
519			  [7] = "Mobile Pentium 75 - 200",
520			  [8] = "Mobile Pentium MMX"
 
521		  }
522		},
523		{ .vendor = X86_VENDOR_INTEL, .family = 6, .model_names =
524		  {
525			  [0] = "Pentium Pro A-step",
526			  [1] = "Pentium Pro",
527			  [3] = "Pentium II (Klamath)",
528			  [4] = "Pentium II (Deschutes)",
529			  [5] = "Pentium II (Deschutes)",
530			  [6] = "Mobile Pentium II",
531			  [7] = "Pentium III (Katmai)",
532			  [8] = "Pentium III (Coppermine)",
533			  [10] = "Pentium III (Cascades)",
534			  [11] = "Pentium III (Tualatin)",
535		  }
536		},
537		{ .vendor = X86_VENDOR_INTEL, .family = 15, .model_names =
538		  {
539			  [0] = "Pentium 4 (Unknown)",
540			  [1] = "Pentium 4 (Willamette)",
541			  [2] = "Pentium 4 (Northwood)",
542			  [4] = "Pentium 4 (Foster)",
543			  [5] = "Pentium 4 (Foster)",
544		  }
545		},
546	},
547	.c_size_cache	= intel_size_cache,
548#endif
 
549	.c_early_init   = early_init_intel,
 
550	.c_init		= init_intel,
551	.c_x86_vendor	= X86_VENDOR_INTEL,
552};
553
554cpu_dev_register(intel_cpu_dev);
555
v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/kernel.h>
   3#include <linux/pgtable.h>
   4
   5#include <linux/string.h>
   6#include <linux/bitops.h>
   7#include <linux/smp.h>
   8#include <linux/sched.h>
   9#include <linux/sched/clock.h>
  10#include <linux/thread_info.h>
  11#include <linux/init.h>
  12#include <linux/uaccess.h>
  13
  14#include <asm/cpufeature.h>
 
  15#include <asm/msr.h>
  16#include <asm/bugs.h>
  17#include <asm/cpu.h>
  18#include <asm/intel-family.h>
  19#include <asm/microcode_intel.h>
  20#include <asm/hwcap2.h>
  21#include <asm/elf.h>
  22#include <asm/cpu_device_id.h>
  23#include <asm/cmdline.h>
  24#include <asm/traps.h>
  25#include <asm/resctrl.h>
  26#include <asm/numa.h>
  27
  28#ifdef CONFIG_X86_64
  29#include <linux/topology.h>
 
  30#endif
  31
  32#include "cpu.h"
  33
  34#ifdef CONFIG_X86_LOCAL_APIC
  35#include <asm/mpspec.h>
  36#include <asm/apic.h>
  37#endif
  38
  39enum split_lock_detect_state {
  40	sld_off = 0,
  41	sld_warn,
  42	sld_fatal,
  43};
  44
  45/*
  46 * Default to sld_off because most systems do not support split lock detection
  47 * split_lock_setup() will switch this to sld_warn on systems that support
  48 * split lock detect, unless there is a command line override.
  49 */
  50static enum split_lock_detect_state sld_state __ro_after_init = sld_off;
  51static u64 msr_test_ctrl_cache __ro_after_init;
  52
  53/*
  54 * With a name like MSR_TEST_CTL it should go without saying, but don't touch
  55 * MSR_TEST_CTL unless the CPU is one of the whitelisted models.  Writing it
  56 * on CPUs that do not support SLD can cause fireworks, even when writing '0'.
  57 */
  58static bool cpu_model_supports_sld __ro_after_init;
  59
  60/*
  61 * Processors which have self-snooping capability can handle conflicting
  62 * memory type across CPUs by snooping its own cache. However, there exists
  63 * CPU models in which having conflicting memory types still leads to
  64 * unpredictable behavior, machine check errors, or hangs. Clear this
  65 * feature to prevent its use on machines with known erratas.
  66 */
  67static void check_memory_type_self_snoop_errata(struct cpuinfo_x86 *c)
  68{
  69	switch (c->x86_model) {
  70	case INTEL_FAM6_CORE_YONAH:
  71	case INTEL_FAM6_CORE2_MEROM:
  72	case INTEL_FAM6_CORE2_MEROM_L:
  73	case INTEL_FAM6_CORE2_PENRYN:
  74	case INTEL_FAM6_CORE2_DUNNINGTON:
  75	case INTEL_FAM6_NEHALEM:
  76	case INTEL_FAM6_NEHALEM_G:
  77	case INTEL_FAM6_NEHALEM_EP:
  78	case INTEL_FAM6_NEHALEM_EX:
  79	case INTEL_FAM6_WESTMERE:
  80	case INTEL_FAM6_WESTMERE_EP:
  81	case INTEL_FAM6_SANDYBRIDGE:
  82		setup_clear_cpu_cap(X86_FEATURE_SELFSNOOP);
  83	}
  84}
  85
  86static bool ring3mwait_disabled __read_mostly;
  87
  88static int __init ring3mwait_disable(char *__unused)
  89{
  90	ring3mwait_disabled = true;
  91	return 0;
  92}
  93__setup("ring3mwait=disable", ring3mwait_disable);
  94
  95static void probe_xeon_phi_r3mwait(struct cpuinfo_x86 *c)
  96{
  97	/*
  98	 * Ring 3 MONITOR/MWAIT feature cannot be detected without
  99	 * cpu model and family comparison.
 100	 */
 101	if (c->x86 != 6)
 102		return;
 103	switch (c->x86_model) {
 104	case INTEL_FAM6_XEON_PHI_KNL:
 105	case INTEL_FAM6_XEON_PHI_KNM:
 106		break;
 107	default:
 108		return;
 109	}
 110
 111	if (ring3mwait_disabled)
 112		return;
 113
 114	set_cpu_cap(c, X86_FEATURE_RING3MWAIT);
 115	this_cpu_or(msr_misc_features_shadow,
 116		    1UL << MSR_MISC_FEATURES_ENABLES_RING3MWAIT_BIT);
 117
 118	if (c == &boot_cpu_data)
 119		ELF_HWCAP2 |= HWCAP2_RING3MWAIT;
 120}
 121
 122/*
 123 * Early microcode releases for the Spectre v2 mitigation were broken.
 124 * Information taken from;
 125 * - https://newsroom.intel.com/wp-content/uploads/sites/11/2018/03/microcode-update-guidance.pdf
 126 * - https://kb.vmware.com/s/article/52345
 127 * - Microcode revisions observed in the wild
 128 * - Release note from 20180108 microcode release
 129 */
 130struct sku_microcode {
 131	u8 model;
 132	u8 stepping;
 133	u32 microcode;
 134};
 135static const struct sku_microcode spectre_bad_microcodes[] = {
 136	{ INTEL_FAM6_KABYLAKE,		0x0B,	0x80 },
 137	{ INTEL_FAM6_KABYLAKE,		0x0A,	0x80 },
 138	{ INTEL_FAM6_KABYLAKE,		0x09,	0x80 },
 139	{ INTEL_FAM6_KABYLAKE_L,	0x0A,	0x80 },
 140	{ INTEL_FAM6_KABYLAKE_L,	0x09,	0x80 },
 141	{ INTEL_FAM6_SKYLAKE_X,		0x03,	0x0100013e },
 142	{ INTEL_FAM6_SKYLAKE_X,		0x04,	0x0200003c },
 143	{ INTEL_FAM6_BROADWELL,		0x04,	0x28 },
 144	{ INTEL_FAM6_BROADWELL_G,	0x01,	0x1b },
 145	{ INTEL_FAM6_BROADWELL_D,	0x02,	0x14 },
 146	{ INTEL_FAM6_BROADWELL_D,	0x03,	0x07000011 },
 147	{ INTEL_FAM6_BROADWELL_X,	0x01,	0x0b000025 },
 148	{ INTEL_FAM6_HASWELL_L,		0x01,	0x21 },
 149	{ INTEL_FAM6_HASWELL_G,		0x01,	0x18 },
 150	{ INTEL_FAM6_HASWELL,		0x03,	0x23 },
 151	{ INTEL_FAM6_HASWELL_X,		0x02,	0x3b },
 152	{ INTEL_FAM6_HASWELL_X,		0x04,	0x10 },
 153	{ INTEL_FAM6_IVYBRIDGE_X,	0x04,	0x42a },
 154	/* Observed in the wild */
 155	{ INTEL_FAM6_SANDYBRIDGE_X,	0x06,	0x61b },
 156	{ INTEL_FAM6_SANDYBRIDGE_X,	0x07,	0x712 },
 157};
 158
 159static bool bad_spectre_microcode(struct cpuinfo_x86 *c)
 160{
 161	int i;
 162
 163	/*
 164	 * We know that the hypervisor lie to us on the microcode version so
 165	 * we may as well hope that it is running the correct version.
 166	 */
 167	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
 168		return false;
 169
 170	if (c->x86 != 6)
 171		return false;
 172
 173	for (i = 0; i < ARRAY_SIZE(spectre_bad_microcodes); i++) {
 174		if (c->x86_model == spectre_bad_microcodes[i].model &&
 175		    c->x86_stepping == spectre_bad_microcodes[i].stepping)
 176			return (c->microcode <= spectre_bad_microcodes[i].microcode);
 177	}
 178	return false;
 179}
 180
 181static void early_init_intel(struct cpuinfo_x86 *c)
 182{
 183	u64 misc_enable;
 184
 185	/* Unmask CPUID levels if masked: */
 186	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
 187		if (msr_clear_bit(MSR_IA32_MISC_ENABLE,
 188				  MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT) > 0) {
 
 
 
 189			c->cpuid_level = cpuid_eax(0);
 190			get_cpu_cap(c);
 191		}
 192	}
 193
 194	if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
 195		(c->x86 == 0x6 && c->x86_model >= 0x0e))
 196		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 197
 198	if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64))
 199		c->microcode = intel_get_microcode_revision();
 200
 201	/* Now if any of them are set, check the blacklist and clear the lot */
 202	if ((cpu_has(c, X86_FEATURE_SPEC_CTRL) ||
 203	     cpu_has(c, X86_FEATURE_INTEL_STIBP) ||
 204	     cpu_has(c, X86_FEATURE_IBRS) || cpu_has(c, X86_FEATURE_IBPB) ||
 205	     cpu_has(c, X86_FEATURE_STIBP)) && bad_spectre_microcode(c)) {
 206		pr_warn("Intel Spectre v2 broken microcode detected; disabling Speculation Control\n");
 207		setup_clear_cpu_cap(X86_FEATURE_IBRS);
 208		setup_clear_cpu_cap(X86_FEATURE_IBPB);
 209		setup_clear_cpu_cap(X86_FEATURE_STIBP);
 210		setup_clear_cpu_cap(X86_FEATURE_SPEC_CTRL);
 211		setup_clear_cpu_cap(X86_FEATURE_MSR_SPEC_CTRL);
 212		setup_clear_cpu_cap(X86_FEATURE_INTEL_STIBP);
 213		setup_clear_cpu_cap(X86_FEATURE_SSBD);
 214		setup_clear_cpu_cap(X86_FEATURE_SPEC_CTRL_SSBD);
 215	}
 216
 217	/*
 218	 * Atom erratum AAE44/AAF40/AAG38/AAH41:
 219	 *
 220	 * A race condition between speculative fetches and invalidating
 221	 * a large page.  This is worked around in microcode, but we
 222	 * need the microcode to have already been loaded... so if it is
 223	 * not, recommend a BIOS update and disable large pages.
 224	 */
 225	if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_stepping <= 2 &&
 226	    c->microcode < 0x20e) {
 227		pr_warn("Atom PSE erratum detected, BIOS microcode update recommended\n");
 228		clear_cpu_cap(c, X86_FEATURE_PSE);
 229	}
 230
 231#ifdef CONFIG_X86_64
 232	set_cpu_cap(c, X86_FEATURE_SYSENTER32);
 233#else
 234	/* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
 235	if (c->x86 == 15 && c->x86_cache_alignment == 64)
 236		c->x86_cache_alignment = 128;
 237#endif
 238
 239	/* CPUID workaround for 0F33/0F34 CPU */
 240	if (c->x86 == 0xF && c->x86_model == 0x3
 241	    && (c->x86_stepping == 0x3 || c->x86_stepping == 0x4))
 242		c->x86_phys_bits = 36;
 243
 244	/*
 245	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
 246	 * with P/T states and does not stop in deep C-states.
 247	 *
 248	 * It is also reliable across cores and sockets. (but not across
 249	 * cabinets - we turn it off in that case explicitly.)
 250	 */
 251	if (c->x86_power & (1 << 8)) {
 252		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 253		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
 254	}
 255
 256	/* Penwell and Cloverview have the TSC which doesn't sleep on S3 */
 257	if (c->x86 == 6) {
 258		switch (c->x86_model) {
 259		case INTEL_FAM6_ATOM_SALTWELL_MID:
 260		case INTEL_FAM6_ATOM_SALTWELL_TABLET:
 261		case INTEL_FAM6_ATOM_SILVERMONT_MID:
 262		case INTEL_FAM6_ATOM_AIRMONT_NP:
 263			set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC_S3);
 264			break;
 265		default:
 266			break;
 267		}
 268	}
 269
 270	/*
 271	 * There is a known erratum on Pentium III and Core Solo
 272	 * and Core Duo CPUs.
 273	 * " Page with PAT set to WC while associated MTRR is UC
 274	 *   may consolidate to UC "
 275	 * Because of this erratum, it is better to stick with
 276	 * setting WC in MTRR rather than using PAT on these CPUs.
 277	 *
 278	 * Enable PAT WC only on P4, Core 2 or later CPUs.
 279	 */
 280	if (c->x86 == 6 && c->x86_model < 15)
 281		clear_cpu_cap(c, X86_FEATURE_PAT);
 282
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 283	/*
 284	 * If fast string is not enabled in IA32_MISC_ENABLE for any reason,
 285	 * clear the fast string and enhanced fast string CPU capabilities.
 286	 */
 287	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
 288		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
 289		if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
 290			pr_info("Disabled fast string operations\n");
 291			setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
 292			setup_clear_cpu_cap(X86_FEATURE_ERMS);
 293		}
 294	}
 295
 296	/*
 297	 * Intel Quark Core DevMan_001.pdf section 6.4.11
 298	 * "The operating system also is required to invalidate (i.e., flush)
 299	 *  the TLB when any changes are made to any of the page table entries.
 300	 *  The operating system must reload CR3 to cause the TLB to be flushed"
 301	 *
 302	 * As a result, boot_cpu_has(X86_FEATURE_PGE) in arch/x86/include/asm/tlbflush.h
 303	 * should be false so that __flush_tlb_all() causes CR3 insted of CR4.PGE
 304	 * to be modified.
 305	 */
 306	if (c->x86 == 5 && c->x86_model == 9) {
 307		pr_info("Disabling PGE capability bit\n");
 308		setup_clear_cpu_cap(X86_FEATURE_PGE);
 309	}
 310
 311	if (c->cpuid_level >= 0x00000001) {
 312		u32 eax, ebx, ecx, edx;
 313
 314		cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
 315		/*
 316		 * If HTT (EDX[28]) is set EBX[16:23] contain the number of
 317		 * apicids which are reserved per package. Store the resulting
 318		 * shift value for the package management code.
 319		 */
 320		if (edx & (1U << 28))
 321			c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
 322	}
 323
 324	check_memory_type_self_snoop_errata(c);
 325
 326	/*
 327	 * Get the number of SMT siblings early from the extended topology
 328	 * leaf, if available. Otherwise try the legacy SMT detection.
 329	 */
 330	if (detect_extended_topology_early(c) < 0)
 331		detect_ht_early(c);
 332}
 333
 334static void bsp_init_intel(struct cpuinfo_x86 *c)
 335{
 336	resctrl_cpu_detect(c);
 337}
 338
 339#ifdef CONFIG_X86_32
 340/*
 341 *	Early probe support logic for ppro memory erratum #50
 342 *
 343 *	This is called before we do cpu ident work
 344 */
 345
 346int ppro_with_ram_bug(void)
 347{
 348	/* Uses data from early_cpu_detect now */
 349	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
 350	    boot_cpu_data.x86 == 6 &&
 351	    boot_cpu_data.x86_model == 1 &&
 352	    boot_cpu_data.x86_stepping < 8) {
 353		pr_info("Pentium Pro with Errata#50 detected. Taking evasive action.\n");
 354		return 1;
 355	}
 356	return 0;
 357}
 358
 359static void intel_smp_check(struct cpuinfo_x86 *c)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 360{
 361	/* calling is from identify_secondary_cpu() ? */
 362	if (!c->cpu_index)
 363		return;
 364
 365	/*
 366	 * Mask B, Pentium, but not Pentium MMX
 367	 */
 368	if (c->x86 == 5 &&
 369	    c->x86_stepping >= 1 && c->x86_stepping <= 4 &&
 370	    c->x86_model <= 3) {
 371		/*
 372		 * Remember we have B step Pentia with bugs
 373		 */
 374		WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
 375				    "with B stepping processors.\n");
 376	}
 377}
 378
 379static int forcepae;
 380static int __init forcepae_setup(char *__unused)
 381{
 382	forcepae = 1;
 383	return 1;
 384}
 385__setup("forcepae", forcepae_setup);
 386
 387static void intel_workarounds(struct cpuinfo_x86 *c)
 388{
 389#ifdef CONFIG_X86_F00F_BUG
 390	/*
 391	 * All models of Pentium and Pentium with MMX technology CPUs
 392	 * have the F0 0F bug, which lets nonprivileged users lock up the
 393	 * system. Announce that the fault handler will be checking for it.
 394	 * The Quark is also family 5, but does not have the same bug.
 395	 */
 396	clear_cpu_bug(c, X86_BUG_F00F);
 397	if (c->x86 == 5 && c->x86_model < 9) {
 398		static int f00f_workaround_enabled;
 399
 400		set_cpu_bug(c, X86_BUG_F00F);
 401		if (!f00f_workaround_enabled) {
 402			pr_notice("Intel Pentium with F0 0F bug - workaround enabled.\n");
 
 403			f00f_workaround_enabled = 1;
 404		}
 405	}
 406#endif
 407
 408	/*
 409	 * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
 410	 * model 3 mask 3
 411	 */
 412	if ((c->x86<<8 | c->x86_model<<4 | c->x86_stepping) < 0x633)
 413		clear_cpu_cap(c, X86_FEATURE_SEP);
 414
 415	/*
 416	 * PAE CPUID issue: many Pentium M report no PAE but may have a
 417	 * functionally usable PAE implementation.
 418	 * Forcefully enable PAE if kernel parameter "forcepae" is present.
 419	 */
 420	if (forcepae) {
 421		pr_warn("PAE forced!\n");
 422		set_cpu_cap(c, X86_FEATURE_PAE);
 423		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
 424	}
 425
 426	/*
 427	 * P4 Xeon erratum 037 workaround.
 428	 * Hardware prefetcher may cause stale data to be loaded into the cache.
 429	 */
 430	if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_stepping == 1)) {
 431		if (msr_set_bit(MSR_IA32_MISC_ENABLE,
 432				MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE_BIT) > 0) {
 433			pr_info("CPU: C0 stepping P4 Xeon detected.\n");
 434			pr_info("CPU: Disabling hardware prefetching (Erratum 037)\n");
 
 
 435		}
 436	}
 437
 438	/*
 439	 * See if we have a good local APIC by checking for buggy Pentia,
 440	 * i.e. all B steppings and the C2 stepping of P54C when using their
 441	 * integrated APIC (see 11AP erratum in "Pentium Processor
 442	 * Specification Update").
 443	 */
 444	if (boot_cpu_has(X86_FEATURE_APIC) && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
 445	    (c->x86_stepping < 0x6 || c->x86_stepping == 0xb))
 446		set_cpu_bug(c, X86_BUG_11AP);
 447
 448
 449#ifdef CONFIG_X86_INTEL_USERCOPY
 450	/*
 451	 * Set up the preferred alignment for movsl bulk memory moves
 452	 */
 453	switch (c->x86) {
 454	case 4:		/* 486: untested */
 455		break;
 456	case 5:		/* Old Pentia: untested */
 457		break;
 458	case 6:		/* PII/PIII only like movsl with 8-byte alignment */
 459		movsl_mask.mask = 7;
 460		break;
 461	case 15:	/* P4 is OK down to 8-byte alignment */
 462		movsl_mask.mask = 7;
 463		break;
 464	}
 465#endif
 466
 
 
 
 
 467	intel_smp_check(c);
 468}
 469#else
 470static void intel_workarounds(struct cpuinfo_x86 *c)
 471{
 472}
 473#endif
 474
 475static void srat_detect_node(struct cpuinfo_x86 *c)
 476{
 477#ifdef CONFIG_NUMA
 478	unsigned node;
 479	int cpu = smp_processor_id();
 480
 481	/* Don't do the funky fallback heuristics the AMD version employs
 482	   for now. */
 483	node = numa_cpu_node(cpu);
 484	if (node == NUMA_NO_NODE || !node_online(node)) {
 485		/* reuse the value from init_cpu_to_node() */
 486		node = cpu_to_node(cpu);
 487	}
 488	numa_set_node(cpu, node);
 489#endif
 490}
 491
 492#define MSR_IA32_TME_ACTIVATE		0x982
 493
 494/* Helpers to access TME_ACTIVATE MSR */
 495#define TME_ACTIVATE_LOCKED(x)		(x & 0x1)
 496#define TME_ACTIVATE_ENABLED(x)		(x & 0x2)
 497
 498#define TME_ACTIVATE_POLICY(x)		((x >> 4) & 0xf)	/* Bits 7:4 */
 499#define TME_ACTIVATE_POLICY_AES_XTS_128	0
 500
 501#define TME_ACTIVATE_KEYID_BITS(x)	((x >> 32) & 0xf)	/* Bits 35:32 */
 502
 503#define TME_ACTIVATE_CRYPTO_ALGS(x)	((x >> 48) & 0xffff)	/* Bits 63:48 */
 504#define TME_ACTIVATE_CRYPTO_AES_XTS_128	1
 505
 506/* Values for mktme_status (SW only construct) */
 507#define MKTME_ENABLED			0
 508#define MKTME_DISABLED			1
 509#define MKTME_UNINITIALIZED		2
 510static int mktme_status = MKTME_UNINITIALIZED;
 511
 512static void detect_tme(struct cpuinfo_x86 *c)
 513{
 514	u64 tme_activate, tme_policy, tme_crypto_algs;
 515	int keyid_bits = 0, nr_keyids = 0;
 516	static u64 tme_activate_cpu0 = 0;
 517
 518	rdmsrl(MSR_IA32_TME_ACTIVATE, tme_activate);
 519
 520	if (mktme_status != MKTME_UNINITIALIZED) {
 521		if (tme_activate != tme_activate_cpu0) {
 522			/* Broken BIOS? */
 523			pr_err_once("x86/tme: configuration is inconsistent between CPUs\n");
 524			pr_err_once("x86/tme: MKTME is not usable\n");
 525			mktme_status = MKTME_DISABLED;
 526
 527			/* Proceed. We may need to exclude bits from x86_phys_bits. */
 528		}
 529	} else {
 530		tme_activate_cpu0 = tme_activate;
 531	}
 532
 533	if (!TME_ACTIVATE_LOCKED(tme_activate) || !TME_ACTIVATE_ENABLED(tme_activate)) {
 534		pr_info_once("x86/tme: not enabled by BIOS\n");
 535		mktme_status = MKTME_DISABLED;
 536		return;
 537	}
 538
 539	if (mktme_status != MKTME_UNINITIALIZED)
 540		goto detect_keyid_bits;
 541
 542	pr_info("x86/tme: enabled by BIOS\n");
 543
 544	tme_policy = TME_ACTIVATE_POLICY(tme_activate);
 545	if (tme_policy != TME_ACTIVATE_POLICY_AES_XTS_128)
 546		pr_warn("x86/tme: Unknown policy is active: %#llx\n", tme_policy);
 547
 548	tme_crypto_algs = TME_ACTIVATE_CRYPTO_ALGS(tme_activate);
 549	if (!(tme_crypto_algs & TME_ACTIVATE_CRYPTO_AES_XTS_128)) {
 550		pr_err("x86/mktme: No known encryption algorithm is supported: %#llx\n",
 551				tme_crypto_algs);
 552		mktme_status = MKTME_DISABLED;
 553	}
 554detect_keyid_bits:
 555	keyid_bits = TME_ACTIVATE_KEYID_BITS(tme_activate);
 556	nr_keyids = (1UL << keyid_bits) - 1;
 557	if (nr_keyids) {
 558		pr_info_once("x86/mktme: enabled by BIOS\n");
 559		pr_info_once("x86/mktme: %d KeyIDs available\n", nr_keyids);
 560	} else {
 561		pr_info_once("x86/mktme: disabled by BIOS\n");
 562	}
 563
 564	if (mktme_status == MKTME_UNINITIALIZED) {
 565		/* MKTME is usable */
 566		mktme_status = MKTME_ENABLED;
 567	}
 568
 569	/*
 570	 * KeyID bits effectively lower the number of physical address
 571	 * bits.  Update cpuinfo_x86::x86_phys_bits accordingly.
 572	 */
 573	c->x86_phys_bits -= keyid_bits;
 574}
 575
 576static void init_cpuid_fault(struct cpuinfo_x86 *c)
 577{
 578	u64 msr;
 579
 580	if (!rdmsrl_safe(MSR_PLATFORM_INFO, &msr)) {
 581		if (msr & MSR_PLATFORM_INFO_CPUID_FAULT)
 582			set_cpu_cap(c, X86_FEATURE_CPUID_FAULT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 583	}
 584}
 585
 586static void init_intel_misc_features(struct cpuinfo_x86 *c)
 587{
 588	u64 msr;
 589
 590	if (rdmsrl_safe(MSR_MISC_FEATURES_ENABLES, &msr))
 591		return;
 592
 593	/* Clear all MISC features */
 594	this_cpu_write(msr_misc_features_shadow, 0);
 595
 596	/* Check features and update capabilities and shadow control bits */
 597	init_cpuid_fault(c);
 598	probe_xeon_phi_r3mwait(c);
 599
 600	msr = this_cpu_read(msr_misc_features_shadow);
 601	wrmsrl(MSR_MISC_FEATURES_ENABLES, msr);
 602}
 603
 604static void split_lock_init(void);
 605
 606static void init_intel(struct cpuinfo_x86 *c)
 607{
 608	early_init_intel(c);
 609
 610	intel_workarounds(c);
 611
 612	/*
 613	 * Detect the extended topology information if available. This
 614	 * will reinitialise the initial_apicid which will be used
 615	 * in init_intel_cacheinfo()
 616	 */
 617	detect_extended_topology(c);
 618
 619	if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
 620		/*
 621		 * let's use the legacy cpuid vector 0x1 and 0x4 for topology
 622		 * detection.
 623		 */
 624		detect_num_cpu_cores(c);
 625#ifdef CONFIG_X86_32
 626		detect_ht(c);
 627#endif
 628	}
 629
 630	init_intel_cacheinfo(c);
 631
 632	if (c->cpuid_level > 9) {
 633		unsigned eax = cpuid_eax(10);
 634		/* Check for version and the number of counters */
 635		if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
 636			set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
 637	}
 638
 639	if (cpu_has(c, X86_FEATURE_XMM2))
 640		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
 641
 642	if (boot_cpu_has(X86_FEATURE_DS)) {
 643		unsigned int l1, l2;
 644
 645		rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
 646		if (!(l1 & (1<<11)))
 647			set_cpu_cap(c, X86_FEATURE_BTS);
 648		if (!(l1 & (1<<12)))
 649			set_cpu_cap(c, X86_FEATURE_PEBS);
 650	}
 651
 652	if (c->x86 == 6 && boot_cpu_has(X86_FEATURE_CLFLUSH) &&
 653	    (c->x86_model == 29 || c->x86_model == 46 || c->x86_model == 47))
 654		set_cpu_bug(c, X86_BUG_CLFLUSH_MONITOR);
 655
 656	if (c->x86 == 6 && boot_cpu_has(X86_FEATURE_MWAIT) &&
 657		((c->x86_model == INTEL_FAM6_ATOM_GOLDMONT)))
 658		set_cpu_bug(c, X86_BUG_MONITOR);
 659
 660#ifdef CONFIG_X86_64
 661	if (c->x86 == 15)
 662		c->x86_cache_alignment = c->x86_clflush_size * 2;
 663	if (c->x86 == 6)
 664		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 665#else
 666	/*
 667	 * Names for the Pentium II/Celeron processors
 668	 * detectable only by also checking the cache size.
 669	 * Dixon is NOT a Celeron.
 670	 */
 671	if (c->x86 == 6) {
 672		unsigned int l2 = c->x86_cache_size;
 673		char *p = NULL;
 674
 675		switch (c->x86_model) {
 676		case 5:
 677			if (l2 == 0)
 678				p = "Celeron (Covington)";
 679			else if (l2 == 256)
 680				p = "Mobile Pentium II (Dixon)";
 681			break;
 682
 683		case 6:
 684			if (l2 == 128)
 685				p = "Celeron (Mendocino)";
 686			else if (c->x86_stepping == 0 || c->x86_stepping == 5)
 687				p = "Celeron-A";
 688			break;
 689
 690		case 8:
 691			if (l2 == 128)
 692				p = "Celeron (Coppermine)";
 693			break;
 694		}
 695
 696		if (p)
 697			strcpy(c->x86_model_id, p);
 698	}
 699
 700	if (c->x86 == 15)
 701		set_cpu_cap(c, X86_FEATURE_P4);
 702	if (c->x86 == 6)
 703		set_cpu_cap(c, X86_FEATURE_P3);
 704#endif
 705
 
 
 
 
 
 
 
 
 
 
 
 706	/* Work around errata */
 707	srat_detect_node(c);
 708
 709	init_ia32_feat_ctl(c);
 
 710
 711	if (cpu_has(c, X86_FEATURE_TME))
 712		detect_tme(c);
 713
 714	init_intel_misc_features(c);
 715
 716	if (tsx_ctrl_state == TSX_CTRL_ENABLE)
 717		tsx_enable();
 718	if (tsx_ctrl_state == TSX_CTRL_DISABLE)
 719		tsx_disable();
 720
 721	split_lock_init();
 
 
 
 
 
 
 722}
 723
 724#ifdef CONFIG_X86_32
 725static unsigned int intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
 726{
 727	/*
 728	 * Intel PIII Tualatin. This comes in two flavours.
 729	 * One has 256kb of cache, the other 512. We have no way
 730	 * to determine which, so we use a boottime override
 731	 * for the 512kb model, and assume 256 otherwise.
 732	 */
 733	if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
 734		size = 256;
 735
 736	/*
 737	 * Intel Quark SoC X1000 contains a 4-way set associative
 738	 * 16K cache with a 16 byte cache line and 256 lines per tag
 739	 */
 740	if ((c->x86 == 5) && (c->x86_model == 9))
 741		size = 16;
 742	return size;
 743}
 744#endif
 745
 746#define TLB_INST_4K	0x01
 747#define TLB_INST_4M	0x02
 748#define TLB_INST_2M_4M	0x03
 749
 750#define TLB_INST_ALL	0x05
 751#define TLB_INST_1G	0x06
 752
 753#define TLB_DATA_4K	0x11
 754#define TLB_DATA_4M	0x12
 755#define TLB_DATA_2M_4M	0x13
 756#define TLB_DATA_4K_4M	0x14
 757
 758#define TLB_DATA_1G	0x16
 759
 760#define TLB_DATA0_4K	0x21
 761#define TLB_DATA0_4M	0x22
 762#define TLB_DATA0_2M_4M	0x23
 763
 764#define STLB_4K		0x41
 765#define STLB_4K_2M	0x42
 766
 767static const struct _tlb_table intel_tlb_table[] = {
 768	{ 0x01, TLB_INST_4K,		32,	" TLB_INST 4 KByte pages, 4-way set associative" },
 769	{ 0x02, TLB_INST_4M,		2,	" TLB_INST 4 MByte pages, full associative" },
 770	{ 0x03, TLB_DATA_4K,		64,	" TLB_DATA 4 KByte pages, 4-way set associative" },
 771	{ 0x04, TLB_DATA_4M,		8,	" TLB_DATA 4 MByte pages, 4-way set associative" },
 772	{ 0x05, TLB_DATA_4M,		32,	" TLB_DATA 4 MByte pages, 4-way set associative" },
 773	{ 0x0b, TLB_INST_4M,		4,	" TLB_INST 4 MByte pages, 4-way set associative" },
 774	{ 0x4f, TLB_INST_4K,		32,	" TLB_INST 4 KByte pages" },
 775	{ 0x50, TLB_INST_ALL,		64,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
 776	{ 0x51, TLB_INST_ALL,		128,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
 777	{ 0x52, TLB_INST_ALL,		256,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
 778	{ 0x55, TLB_INST_2M_4M,		7,	" TLB_INST 2-MByte or 4-MByte pages, fully associative" },
 779	{ 0x56, TLB_DATA0_4M,		16,	" TLB_DATA0 4 MByte pages, 4-way set associative" },
 780	{ 0x57, TLB_DATA0_4K,		16,	" TLB_DATA0 4 KByte pages, 4-way associative" },
 781	{ 0x59, TLB_DATA0_4K,		16,	" TLB_DATA0 4 KByte pages, fully associative" },
 782	{ 0x5a, TLB_DATA0_2M_4M,	32,	" TLB_DATA0 2-MByte or 4 MByte pages, 4-way set associative" },
 783	{ 0x5b, TLB_DATA_4K_4M,		64,	" TLB_DATA 4 KByte and 4 MByte pages" },
 784	{ 0x5c, TLB_DATA_4K_4M,		128,	" TLB_DATA 4 KByte and 4 MByte pages" },
 785	{ 0x5d, TLB_DATA_4K_4M,		256,	" TLB_DATA 4 KByte and 4 MByte pages" },
 786	{ 0x61, TLB_INST_4K,		48,	" TLB_INST 4 KByte pages, full associative" },
 787	{ 0x63, TLB_DATA_1G,		4,	" TLB_DATA 1 GByte pages, 4-way set associative" },
 788	{ 0x6b, TLB_DATA_4K,		256,	" TLB_DATA 4 KByte pages, 8-way associative" },
 789	{ 0x6c, TLB_DATA_2M_4M,		128,	" TLB_DATA 2 MByte or 4 MByte pages, 8-way associative" },
 790	{ 0x6d, TLB_DATA_1G,		16,	" TLB_DATA 1 GByte pages, fully associative" },
 791	{ 0x76, TLB_INST_2M_4M,		8,	" TLB_INST 2-MByte or 4-MByte pages, fully associative" },
 792	{ 0xb0, TLB_INST_4K,		128,	" TLB_INST 4 KByte pages, 4-way set associative" },
 793	{ 0xb1, TLB_INST_2M_4M,		4,	" TLB_INST 2M pages, 4-way, 8 entries or 4M pages, 4-way entries" },
 794	{ 0xb2, TLB_INST_4K,		64,	" TLB_INST 4KByte pages, 4-way set associative" },
 795	{ 0xb3, TLB_DATA_4K,		128,	" TLB_DATA 4 KByte pages, 4-way set associative" },
 796	{ 0xb4, TLB_DATA_4K,		256,	" TLB_DATA 4 KByte pages, 4-way associative" },
 797	{ 0xb5, TLB_INST_4K,		64,	" TLB_INST 4 KByte pages, 8-way set associative" },
 798	{ 0xb6, TLB_INST_4K,		128,	" TLB_INST 4 KByte pages, 8-way set associative" },
 799	{ 0xba, TLB_DATA_4K,		64,	" TLB_DATA 4 KByte pages, 4-way associative" },
 800	{ 0xc0, TLB_DATA_4K_4M,		8,	" TLB_DATA 4 KByte and 4 MByte pages, 4-way associative" },
 801	{ 0xc1, STLB_4K_2M,		1024,	" STLB 4 KByte and 2 MByte pages, 8-way associative" },
 802	{ 0xc2, TLB_DATA_2M_4M,		16,	" TLB_DATA 2 MByte/4MByte pages, 4-way associative" },
 803	{ 0xca, STLB_4K,		512,	" STLB 4 KByte pages, 4-way associative" },
 804	{ 0x00, 0, 0 }
 805};
 806
 807static void intel_tlb_lookup(const unsigned char desc)
 808{
 809	unsigned char k;
 810	if (desc == 0)
 811		return;
 812
 813	/* look up this descriptor in the table */
 814	for (k = 0; intel_tlb_table[k].descriptor != desc &&
 815	     intel_tlb_table[k].descriptor != 0; k++)
 816		;
 817
 818	if (intel_tlb_table[k].tlb_type == 0)
 819		return;
 820
 821	switch (intel_tlb_table[k].tlb_type) {
 822	case STLB_4K:
 823		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 824			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 825		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 826			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 827		break;
 828	case STLB_4K_2M:
 829		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 830			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 831		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 832			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 833		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
 834			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
 835		if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries)
 836			tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries;
 837		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 838			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 839		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 840			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 841		break;
 842	case TLB_INST_ALL:
 843		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 844			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 845		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
 846			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
 847		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 848			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 849		break;
 850	case TLB_INST_4K:
 851		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 852			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 853		break;
 854	case TLB_INST_4M:
 855		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 856			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 857		break;
 858	case TLB_INST_2M_4M:
 859		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
 860			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
 861		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 862			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 863		break;
 864	case TLB_DATA_4K:
 865	case TLB_DATA0_4K:
 866		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 867			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 868		break;
 869	case TLB_DATA_4M:
 870	case TLB_DATA0_4M:
 871		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 872			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 873		break;
 874	case TLB_DATA_2M_4M:
 875	case TLB_DATA0_2M_4M:
 876		if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries)
 877			tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries;
 878		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 879			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 880		break;
 881	case TLB_DATA_4K_4M:
 882		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 883			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 884		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 885			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 886		break;
 887	case TLB_DATA_1G:
 888		if (tlb_lld_1g[ENTRIES] < intel_tlb_table[k].entries)
 889			tlb_lld_1g[ENTRIES] = intel_tlb_table[k].entries;
 890		break;
 891	}
 892}
 893
 894static void intel_detect_tlb(struct cpuinfo_x86 *c)
 895{
 896	int i, j, n;
 897	unsigned int regs[4];
 898	unsigned char *desc = (unsigned char *)regs;
 899
 900	if (c->cpuid_level < 2)
 901		return;
 902
 903	/* Number of times to iterate */
 904	n = cpuid_eax(2) & 0xFF;
 905
 906	for (i = 0 ; i < n ; i++) {
 907		cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
 908
 909		/* If bit 31 is set, this is an unknown format */
 910		for (j = 0 ; j < 3 ; j++)
 911			if (regs[j] & (1 << 31))
 912				regs[j] = 0;
 913
 914		/* Byte 0 is level count, not a descriptor */
 915		for (j = 1 ; j < 16 ; j++)
 916			intel_tlb_lookup(desc[j]);
 917	}
 918}
 919
 920static const struct cpu_dev intel_cpu_dev = {
 921	.c_vendor	= "Intel",
 922	.c_ident	= { "GenuineIntel" },
 923#ifdef CONFIG_X86_32
 924	.legacy_models = {
 925		{ .family = 4, .model_names =
 926		  {
 927			  [0] = "486 DX-25/33",
 928			  [1] = "486 DX-50",
 929			  [2] = "486 SX",
 930			  [3] = "486 DX/2",
 931			  [4] = "486 SL",
 932			  [5] = "486 SX/2",
 933			  [7] = "486 DX/2-WB",
 934			  [8] = "486 DX/4",
 935			  [9] = "486 DX/4-WB"
 936		  }
 937		},
 938		{ .family = 5, .model_names =
 939		  {
 940			  [0] = "Pentium 60/66 A-step",
 941			  [1] = "Pentium 60/66",
 942			  [2] = "Pentium 75 - 200",
 943			  [3] = "OverDrive PODP5V83",
 944			  [4] = "Pentium MMX",
 945			  [7] = "Mobile Pentium 75 - 200",
 946			  [8] = "Mobile Pentium MMX",
 947			  [9] = "Quark SoC X1000",
 948		  }
 949		},
 950		{ .family = 6, .model_names =
 951		  {
 952			  [0] = "Pentium Pro A-step",
 953			  [1] = "Pentium Pro",
 954			  [3] = "Pentium II (Klamath)",
 955			  [4] = "Pentium II (Deschutes)",
 956			  [5] = "Pentium II (Deschutes)",
 957			  [6] = "Mobile Pentium II",
 958			  [7] = "Pentium III (Katmai)",
 959			  [8] = "Pentium III (Coppermine)",
 960			  [10] = "Pentium III (Cascades)",
 961			  [11] = "Pentium III (Tualatin)",
 962		  }
 963		},
 964		{ .family = 15, .model_names =
 965		  {
 966			  [0] = "Pentium 4 (Unknown)",
 967			  [1] = "Pentium 4 (Willamette)",
 968			  [2] = "Pentium 4 (Northwood)",
 969			  [4] = "Pentium 4 (Foster)",
 970			  [5] = "Pentium 4 (Foster)",
 971		  }
 972		},
 973	},
 974	.legacy_cache_size = intel_size_cache,
 975#endif
 976	.c_detect_tlb	= intel_detect_tlb,
 977	.c_early_init   = early_init_intel,
 978	.c_bsp_init	= bsp_init_intel,
 979	.c_init		= init_intel,
 980	.c_x86_vendor	= X86_VENDOR_INTEL,
 981};
 982
 983cpu_dev_register(intel_cpu_dev);
 984
 985#undef pr_fmt
 986#define pr_fmt(fmt) "x86/split lock detection: " fmt
 987
 988static const struct {
 989	const char			*option;
 990	enum split_lock_detect_state	state;
 991} sld_options[] __initconst = {
 992	{ "off",	sld_off   },
 993	{ "warn",	sld_warn  },
 994	{ "fatal",	sld_fatal },
 995};
 996
 997static inline bool match_option(const char *arg, int arglen, const char *opt)
 998{
 999	int len = strlen(opt);
1000
1001	return len == arglen && !strncmp(arg, opt, len);
1002}
1003
1004static bool split_lock_verify_msr(bool on)
1005{
1006	u64 ctrl, tmp;
1007
1008	if (rdmsrl_safe(MSR_TEST_CTRL, &ctrl))
1009		return false;
1010	if (on)
1011		ctrl |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
1012	else
1013		ctrl &= ~MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
1014	if (wrmsrl_safe(MSR_TEST_CTRL, ctrl))
1015		return false;
1016	rdmsrl(MSR_TEST_CTRL, tmp);
1017	return ctrl == tmp;
1018}
1019
1020static void __init split_lock_setup(void)
1021{
1022	enum split_lock_detect_state state = sld_warn;
1023	char arg[20];
1024	int i, ret;
1025
1026	if (!split_lock_verify_msr(false)) {
1027		pr_info("MSR access failed: Disabled\n");
1028		return;
1029	}
1030
1031	ret = cmdline_find_option(boot_command_line, "split_lock_detect",
1032				  arg, sizeof(arg));
1033	if (ret >= 0) {
1034		for (i = 0; i < ARRAY_SIZE(sld_options); i++) {
1035			if (match_option(arg, ret, sld_options[i].option)) {
1036				state = sld_options[i].state;
1037				break;
1038			}
1039		}
1040	}
1041
1042	switch (state) {
1043	case sld_off:
1044		pr_info("disabled\n");
1045		return;
1046	case sld_warn:
1047		pr_info("warning about user-space split_locks\n");
1048		break;
1049	case sld_fatal:
1050		pr_info("sending SIGBUS on user-space split_locks\n");
1051		break;
1052	}
1053
1054	rdmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache);
1055
1056	if (!split_lock_verify_msr(true)) {
1057		pr_info("MSR access failed: Disabled\n");
1058		return;
1059	}
1060
1061	sld_state = state;
1062	setup_force_cpu_cap(X86_FEATURE_SPLIT_LOCK_DETECT);
1063}
1064
1065/*
1066 * MSR_TEST_CTRL is per core, but we treat it like a per CPU MSR. Locking
1067 * is not implemented as one thread could undo the setting of the other
1068 * thread immediately after dropping the lock anyway.
1069 */
1070static void sld_update_msr(bool on)
1071{
1072	u64 test_ctrl_val = msr_test_ctrl_cache;
1073
1074	if (on)
1075		test_ctrl_val |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
1076
1077	wrmsrl(MSR_TEST_CTRL, test_ctrl_val);
1078}
1079
1080static void split_lock_init(void)
1081{
1082	if (cpu_model_supports_sld)
1083		split_lock_verify_msr(sld_state != sld_off);
1084}
1085
1086static void split_lock_warn(unsigned long ip)
1087{
1088	pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n",
1089			    current->comm, current->pid, ip);
1090
1091	/*
1092	 * Disable the split lock detection for this task so it can make
1093	 * progress and set TIF_SLD so the detection is re-enabled via
1094	 * switch_to_sld() when the task is scheduled out.
1095	 */
1096	sld_update_msr(false);
1097	set_tsk_thread_flag(current, TIF_SLD);
1098}
1099
1100bool handle_guest_split_lock(unsigned long ip)
1101{
1102	if (sld_state == sld_warn) {
1103		split_lock_warn(ip);
1104		return true;
1105	}
1106
1107	pr_warn_once("#AC: %s/%d %s split_lock trap at address: 0x%lx\n",
1108		     current->comm, current->pid,
1109		     sld_state == sld_fatal ? "fatal" : "bogus", ip);
1110
1111	current->thread.error_code = 0;
1112	current->thread.trap_nr = X86_TRAP_AC;
1113	force_sig_fault(SIGBUS, BUS_ADRALN, NULL);
1114	return false;
1115}
1116EXPORT_SYMBOL_GPL(handle_guest_split_lock);
1117
1118bool handle_user_split_lock(struct pt_regs *regs, long error_code)
1119{
1120	if ((regs->flags & X86_EFLAGS_AC) || sld_state == sld_fatal)
1121		return false;
1122	split_lock_warn(regs->ip);
1123	return true;
1124}
1125
1126/*
1127 * This function is called only when switching between tasks with
1128 * different split-lock detection modes. It sets the MSR for the
1129 * mode of the new task. This is right most of the time, but since
1130 * the MSR is shared by hyperthreads on a physical core there can
1131 * be glitches when the two threads need different modes.
1132 */
1133void switch_to_sld(unsigned long tifn)
1134{
1135	sld_update_msr(!(tifn & _TIF_SLD));
1136}
1137
1138/*
1139 * Bits in the IA32_CORE_CAPABILITIES are not architectural, so they should
1140 * only be trusted if it is confirmed that a CPU model implements a
1141 * specific feature at a particular bit position.
1142 *
1143 * The possible driver data field values:
1144 *
1145 * - 0: CPU models that are known to have the per-core split-lock detection
1146 *	feature even though they do not enumerate IA32_CORE_CAPABILITIES.
1147 *
1148 * - 1: CPU models which may enumerate IA32_CORE_CAPABILITIES and if so use
1149 *      bit 5 to enumerate the per-core split-lock detection feature.
1150 */
1151static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = {
1152	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X,		0),
1153	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L,		0),
1154	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D,		0),
1155	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT,	1),
1156	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D,	1),
1157	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_L,	1),
1158	X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L,		1),
1159	X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE,		1),
1160	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X,	1),
1161	X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE,		1),
1162	{}
1163};
1164
1165void __init cpu_set_core_cap_bits(struct cpuinfo_x86 *c)
1166{
1167	const struct x86_cpu_id *m;
1168	u64 ia32_core_caps;
1169
1170	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
1171		return;
1172
1173	m = x86_match_cpu(split_lock_cpu_ids);
1174	if (!m)
1175		return;
1176
1177	switch (m->driver_data) {
1178	case 0:
1179		break;
1180	case 1:
1181		if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES))
1182			return;
1183		rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps);
1184		if (!(ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT))
1185			return;
1186		break;
1187	default:
1188		return;
1189	}
1190
1191	cpu_model_supports_sld = true;
1192	split_lock_setup();
1193}