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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
v5.14.15
   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#include <linux/delay.h>
  14
  15#include <asm/cpufeature.h>
 
  16#include <asm/msr.h>
  17#include <asm/bugs.h>
  18#include <asm/cpu.h>
  19#include <asm/intel-family.h>
  20#include <asm/microcode_intel.h>
  21#include <asm/hwcap2.h>
  22#include <asm/elf.h>
  23#include <asm/cpu_device_id.h>
  24#include <asm/cmdline.h>
  25#include <asm/traps.h>
  26#include <asm/resctrl.h>
  27#include <asm/numa.h>
  28#include <asm/thermal.h>
  29
  30#ifdef CONFIG_X86_64
  31#include <linux/topology.h>
 
  32#endif
  33
  34#include "cpu.h"
  35
  36#ifdef CONFIG_X86_LOCAL_APIC
  37#include <asm/mpspec.h>
  38#include <asm/apic.h>
  39#endif
  40
  41enum split_lock_detect_state {
  42	sld_off = 0,
  43	sld_warn,
  44	sld_fatal,
  45	sld_ratelimit,
  46};
  47
  48/*
  49 * Default to sld_off because most systems do not support split lock detection.
  50 * sld_state_setup() will switch this to sld_warn on systems that support
  51 * split lock/bus lock detect, unless there is a command line override.
  52 */
  53static enum split_lock_detect_state sld_state __ro_after_init = sld_off;
  54static u64 msr_test_ctrl_cache __ro_after_init;
  55
  56/*
  57 * With a name like MSR_TEST_CTL it should go without saying, but don't touch
  58 * MSR_TEST_CTL unless the CPU is one of the whitelisted models.  Writing it
  59 * on CPUs that do not support SLD can cause fireworks, even when writing '0'.
  60 */
  61static bool cpu_model_supports_sld __ro_after_init;
  62
  63/*
  64 * Processors which have self-snooping capability can handle conflicting
  65 * memory type across CPUs by snooping its own cache. However, there exists
  66 * CPU models in which having conflicting memory types still leads to
  67 * unpredictable behavior, machine check errors, or hangs. Clear this
  68 * feature to prevent its use on machines with known erratas.
  69 */
  70static void check_memory_type_self_snoop_errata(struct cpuinfo_x86 *c)
  71{
  72	switch (c->x86_model) {
  73	case INTEL_FAM6_CORE_YONAH:
  74	case INTEL_FAM6_CORE2_MEROM:
  75	case INTEL_FAM6_CORE2_MEROM_L:
  76	case INTEL_FAM6_CORE2_PENRYN:
  77	case INTEL_FAM6_CORE2_DUNNINGTON:
  78	case INTEL_FAM6_NEHALEM:
  79	case INTEL_FAM6_NEHALEM_G:
  80	case INTEL_FAM6_NEHALEM_EP:
  81	case INTEL_FAM6_NEHALEM_EX:
  82	case INTEL_FAM6_WESTMERE:
  83	case INTEL_FAM6_WESTMERE_EP:
  84	case INTEL_FAM6_SANDYBRIDGE:
  85		setup_clear_cpu_cap(X86_FEATURE_SELFSNOOP);
  86	}
  87}
  88
  89static bool ring3mwait_disabled __read_mostly;
  90
  91static int __init ring3mwait_disable(char *__unused)
  92{
  93	ring3mwait_disabled = true;
  94	return 0;
  95}
  96__setup("ring3mwait=disable", ring3mwait_disable);
  97
  98static void probe_xeon_phi_r3mwait(struct cpuinfo_x86 *c)
  99{
 100	/*
 101	 * Ring 3 MONITOR/MWAIT feature cannot be detected without
 102	 * cpu model and family comparison.
 103	 */
 104	if (c->x86 != 6)
 105		return;
 106	switch (c->x86_model) {
 107	case INTEL_FAM6_XEON_PHI_KNL:
 108	case INTEL_FAM6_XEON_PHI_KNM:
 109		break;
 110	default:
 111		return;
 112	}
 113
 114	if (ring3mwait_disabled)
 115		return;
 116
 117	set_cpu_cap(c, X86_FEATURE_RING3MWAIT);
 118	this_cpu_or(msr_misc_features_shadow,
 119		    1UL << MSR_MISC_FEATURES_ENABLES_RING3MWAIT_BIT);
 120
 121	if (c == &boot_cpu_data)
 122		ELF_HWCAP2 |= HWCAP2_RING3MWAIT;
 123}
 124
 125/*
 126 * Early microcode releases for the Spectre v2 mitigation were broken.
 127 * Information taken from;
 128 * - https://newsroom.intel.com/wp-content/uploads/sites/11/2018/03/microcode-update-guidance.pdf
 129 * - https://kb.vmware.com/s/article/52345
 130 * - Microcode revisions observed in the wild
 131 * - Release note from 20180108 microcode release
 132 */
 133struct sku_microcode {
 134	u8 model;
 135	u8 stepping;
 136	u32 microcode;
 137};
 138static const struct sku_microcode spectre_bad_microcodes[] = {
 139	{ INTEL_FAM6_KABYLAKE,		0x0B,	0x80 },
 140	{ INTEL_FAM6_KABYLAKE,		0x0A,	0x80 },
 141	{ INTEL_FAM6_KABYLAKE,		0x09,	0x80 },
 142	{ INTEL_FAM6_KABYLAKE_L,	0x0A,	0x80 },
 143	{ INTEL_FAM6_KABYLAKE_L,	0x09,	0x80 },
 144	{ INTEL_FAM6_SKYLAKE_X,		0x03,	0x0100013e },
 145	{ INTEL_FAM6_SKYLAKE_X,		0x04,	0x0200003c },
 146	{ INTEL_FAM6_BROADWELL,		0x04,	0x28 },
 147	{ INTEL_FAM6_BROADWELL_G,	0x01,	0x1b },
 148	{ INTEL_FAM6_BROADWELL_D,	0x02,	0x14 },
 149	{ INTEL_FAM6_BROADWELL_D,	0x03,	0x07000011 },
 150	{ INTEL_FAM6_BROADWELL_X,	0x01,	0x0b000025 },
 151	{ INTEL_FAM6_HASWELL_L,		0x01,	0x21 },
 152	{ INTEL_FAM6_HASWELL_G,		0x01,	0x18 },
 153	{ INTEL_FAM6_HASWELL,		0x03,	0x23 },
 154	{ INTEL_FAM6_HASWELL_X,		0x02,	0x3b },
 155	{ INTEL_FAM6_HASWELL_X,		0x04,	0x10 },
 156	{ INTEL_FAM6_IVYBRIDGE_X,	0x04,	0x42a },
 157	/* Observed in the wild */
 158	{ INTEL_FAM6_SANDYBRIDGE_X,	0x06,	0x61b },
 159	{ INTEL_FAM6_SANDYBRIDGE_X,	0x07,	0x712 },
 160};
 161
 162static bool bad_spectre_microcode(struct cpuinfo_x86 *c)
 163{
 164	int i;
 165
 166	/*
 167	 * We know that the hypervisor lie to us on the microcode version so
 168	 * we may as well hope that it is running the correct version.
 169	 */
 170	if (cpu_has(c, X86_FEATURE_HYPERVISOR))
 171		return false;
 172
 173	if (c->x86 != 6)
 174		return false;
 175
 176	for (i = 0; i < ARRAY_SIZE(spectre_bad_microcodes); i++) {
 177		if (c->x86_model == spectre_bad_microcodes[i].model &&
 178		    c->x86_stepping == spectre_bad_microcodes[i].stepping)
 179			return (c->microcode <= spectre_bad_microcodes[i].microcode);
 180	}
 181	return false;
 182}
 183
 184static void early_init_intel(struct cpuinfo_x86 *c)
 185{
 186	u64 misc_enable;
 187
 188	/* Unmask CPUID levels if masked: */
 189	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
 190		if (msr_clear_bit(MSR_IA32_MISC_ENABLE,
 191				  MSR_IA32_MISC_ENABLE_LIMIT_CPUID_BIT) > 0) {
 
 
 
 192			c->cpuid_level = cpuid_eax(0);
 193			get_cpu_cap(c);
 194		}
 195	}
 196
 197	if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
 198		(c->x86 == 0x6 && c->x86_model >= 0x0e))
 199		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 200
 201	if (c->x86 >= 6 && !cpu_has(c, X86_FEATURE_IA64))
 202		c->microcode = intel_get_microcode_revision();
 203
 204	/* Now if any of them are set, check the blacklist and clear the lot */
 205	if ((cpu_has(c, X86_FEATURE_SPEC_CTRL) ||
 206	     cpu_has(c, X86_FEATURE_INTEL_STIBP) ||
 207	     cpu_has(c, X86_FEATURE_IBRS) || cpu_has(c, X86_FEATURE_IBPB) ||
 208	     cpu_has(c, X86_FEATURE_STIBP)) && bad_spectre_microcode(c)) {
 209		pr_warn("Intel Spectre v2 broken microcode detected; disabling Speculation Control\n");
 210		setup_clear_cpu_cap(X86_FEATURE_IBRS);
 211		setup_clear_cpu_cap(X86_FEATURE_IBPB);
 212		setup_clear_cpu_cap(X86_FEATURE_STIBP);
 213		setup_clear_cpu_cap(X86_FEATURE_SPEC_CTRL);
 214		setup_clear_cpu_cap(X86_FEATURE_MSR_SPEC_CTRL);
 215		setup_clear_cpu_cap(X86_FEATURE_INTEL_STIBP);
 216		setup_clear_cpu_cap(X86_FEATURE_SSBD);
 217		setup_clear_cpu_cap(X86_FEATURE_SPEC_CTRL_SSBD);
 218	}
 219
 220	/*
 221	 * Atom erratum AAE44/AAF40/AAG38/AAH41:
 222	 *
 223	 * A race condition between speculative fetches and invalidating
 224	 * a large page.  This is worked around in microcode, but we
 225	 * need the microcode to have already been loaded... so if it is
 226	 * not, recommend a BIOS update and disable large pages.
 227	 */
 228	if (c->x86 == 6 && c->x86_model == 0x1c && c->x86_stepping <= 2 &&
 229	    c->microcode < 0x20e) {
 230		pr_warn("Atom PSE erratum detected, BIOS microcode update recommended\n");
 231		clear_cpu_cap(c, X86_FEATURE_PSE);
 232	}
 233
 234#ifdef CONFIG_X86_64
 235	set_cpu_cap(c, X86_FEATURE_SYSENTER32);
 236#else
 237	/* Netburst reports 64 bytes clflush size, but does IO in 128 bytes */
 238	if (c->x86 == 15 && c->x86_cache_alignment == 64)
 239		c->x86_cache_alignment = 128;
 240#endif
 241
 242	/* CPUID workaround for 0F33/0F34 CPU */
 243	if (c->x86 == 0xF && c->x86_model == 0x3
 244	    && (c->x86_stepping == 0x3 || c->x86_stepping == 0x4))
 245		c->x86_phys_bits = 36;
 246
 247	/*
 248	 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate
 249	 * with P/T states and does not stop in deep C-states.
 250	 *
 251	 * It is also reliable across cores and sockets. (but not across
 252	 * cabinets - we turn it off in that case explicitly.)
 253	 */
 254	if (c->x86_power & (1 << 8)) {
 255		set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC);
 256		set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC);
 257	}
 258
 259	/* Penwell and Cloverview have the TSC which doesn't sleep on S3 */
 260	if (c->x86 == 6) {
 261		switch (c->x86_model) {
 262		case INTEL_FAM6_ATOM_SALTWELL_MID:
 263		case INTEL_FAM6_ATOM_SALTWELL_TABLET:
 264		case INTEL_FAM6_ATOM_SILVERMONT_MID:
 265		case INTEL_FAM6_ATOM_AIRMONT_NP:
 266			set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC_S3);
 267			break;
 268		default:
 269			break;
 270		}
 271	}
 272
 273	/*
 274	 * There is a known erratum on Pentium III and Core Solo
 275	 * and Core Duo CPUs.
 276	 * " Page with PAT set to WC while associated MTRR is UC
 277	 *   may consolidate to UC "
 278	 * Because of this erratum, it is better to stick with
 279	 * setting WC in MTRR rather than using PAT on these CPUs.
 280	 *
 281	 * Enable PAT WC only on P4, Core 2 or later CPUs.
 282	 */
 283	if (c->x86 == 6 && c->x86_model < 15)
 284		clear_cpu_cap(c, X86_FEATURE_PAT);
 285
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 286	/*
 287	 * If fast string is not enabled in IA32_MISC_ENABLE for any reason,
 288	 * clear the fast string and enhanced fast string CPU capabilities.
 289	 */
 290	if (c->x86 > 6 || (c->x86 == 6 && c->x86_model >= 0xd)) {
 291		rdmsrl(MSR_IA32_MISC_ENABLE, misc_enable);
 292		if (!(misc_enable & MSR_IA32_MISC_ENABLE_FAST_STRING)) {
 293			pr_info("Disabled fast string operations\n");
 294			setup_clear_cpu_cap(X86_FEATURE_REP_GOOD);
 295			setup_clear_cpu_cap(X86_FEATURE_ERMS);
 296		}
 297	}
 298
 299	/*
 300	 * Intel Quark Core DevMan_001.pdf section 6.4.11
 301	 * "The operating system also is required to invalidate (i.e., flush)
 302	 *  the TLB when any changes are made to any of the page table entries.
 303	 *  The operating system must reload CR3 to cause the TLB to be flushed"
 304	 *
 305	 * As a result, boot_cpu_has(X86_FEATURE_PGE) in arch/x86/include/asm/tlbflush.h
 306	 * should be false so that __flush_tlb_all() causes CR3 instead of CR4.PGE
 307	 * to be modified.
 308	 */
 309	if (c->x86 == 5 && c->x86_model == 9) {
 310		pr_info("Disabling PGE capability bit\n");
 311		setup_clear_cpu_cap(X86_FEATURE_PGE);
 312	}
 313
 314	if (c->cpuid_level >= 0x00000001) {
 315		u32 eax, ebx, ecx, edx;
 316
 317		cpuid(0x00000001, &eax, &ebx, &ecx, &edx);
 318		/*
 319		 * If HTT (EDX[28]) is set EBX[16:23] contain the number of
 320		 * apicids which are reserved per package. Store the resulting
 321		 * shift value for the package management code.
 322		 */
 323		if (edx & (1U << 28))
 324			c->x86_coreid_bits = get_count_order((ebx >> 16) & 0xff);
 325	}
 326
 327	check_memory_type_self_snoop_errata(c);
 328
 329	/*
 330	 * Get the number of SMT siblings early from the extended topology
 331	 * leaf, if available. Otherwise try the legacy SMT detection.
 332	 */
 333	if (detect_extended_topology_early(c) < 0)
 334		detect_ht_early(c);
 335}
 336
 337static void bsp_init_intel(struct cpuinfo_x86 *c)
 338{
 339	resctrl_cpu_detect(c);
 340}
 341
 342#ifdef CONFIG_X86_32
 343/*
 344 *	Early probe support logic for ppro memory erratum #50
 345 *
 346 *	This is called before we do cpu ident work
 347 */
 348
 349int ppro_with_ram_bug(void)
 350{
 351	/* Uses data from early_cpu_detect now */
 352	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL &&
 353	    boot_cpu_data.x86 == 6 &&
 354	    boot_cpu_data.x86_model == 1 &&
 355	    boot_cpu_data.x86_stepping < 8) {
 356		pr_info("Pentium Pro with Errata#50 detected. Taking evasive action.\n");
 357		return 1;
 358	}
 359	return 0;
 360}
 361
 362static void intel_smp_check(struct cpuinfo_x86 *c)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 363{
 364	/* calling is from identify_secondary_cpu() ? */
 365	if (!c->cpu_index)
 366		return;
 367
 368	/*
 369	 * Mask B, Pentium, but not Pentium MMX
 370	 */
 371	if (c->x86 == 5 &&
 372	    c->x86_stepping >= 1 && c->x86_stepping <= 4 &&
 373	    c->x86_model <= 3) {
 374		/*
 375		 * Remember we have B step Pentia with bugs
 376		 */
 377		WARN_ONCE(1, "WARNING: SMP operation may be unreliable"
 378				    "with B stepping processors.\n");
 379	}
 380}
 381
 382static int forcepae;
 383static int __init forcepae_setup(char *__unused)
 384{
 385	forcepae = 1;
 386	return 1;
 387}
 388__setup("forcepae", forcepae_setup);
 389
 390static void intel_workarounds(struct cpuinfo_x86 *c)
 391{
 392#ifdef CONFIG_X86_F00F_BUG
 393	/*
 394	 * All models of Pentium and Pentium with MMX technology CPUs
 395	 * have the F0 0F bug, which lets nonprivileged users lock up the
 396	 * system. Announce that the fault handler will be checking for it.
 397	 * The Quark is also family 5, but does not have the same bug.
 398	 */
 399	clear_cpu_bug(c, X86_BUG_F00F);
 400	if (c->x86 == 5 && c->x86_model < 9) {
 401		static int f00f_workaround_enabled;
 402
 403		set_cpu_bug(c, X86_BUG_F00F);
 404		if (!f00f_workaround_enabled) {
 405			pr_notice("Intel Pentium with F0 0F bug - workaround enabled.\n");
 
 406			f00f_workaround_enabled = 1;
 407		}
 408	}
 409#endif
 410
 411	/*
 412	 * SEP CPUID bug: Pentium Pro reports SEP but doesn't have it until
 413	 * model 3 mask 3
 414	 */
 415	if ((c->x86<<8 | c->x86_model<<4 | c->x86_stepping) < 0x633)
 416		clear_cpu_cap(c, X86_FEATURE_SEP);
 417
 418	/*
 419	 * PAE CPUID issue: many Pentium M report no PAE but may have a
 420	 * functionally usable PAE implementation.
 421	 * Forcefully enable PAE if kernel parameter "forcepae" is present.
 422	 */
 423	if (forcepae) {
 424		pr_warn("PAE forced!\n");
 425		set_cpu_cap(c, X86_FEATURE_PAE);
 426		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_NOW_UNRELIABLE);
 427	}
 428
 429	/*
 430	 * P4 Xeon erratum 037 workaround.
 431	 * Hardware prefetcher may cause stale data to be loaded into the cache.
 432	 */
 433	if ((c->x86 == 15) && (c->x86_model == 1) && (c->x86_stepping == 1)) {
 434		if (msr_set_bit(MSR_IA32_MISC_ENABLE,
 435				MSR_IA32_MISC_ENABLE_PREFETCH_DISABLE_BIT) > 0) {
 436			pr_info("CPU: C0 stepping P4 Xeon detected.\n");
 437			pr_info("CPU: Disabling hardware prefetching (Erratum 037)\n");
 
 
 438		}
 439	}
 440
 441	/*
 442	 * See if we have a good local APIC by checking for buggy Pentia,
 443	 * i.e. all B steppings and the C2 stepping of P54C when using their
 444	 * integrated APIC (see 11AP erratum in "Pentium Processor
 445	 * Specification Update").
 446	 */
 447	if (boot_cpu_has(X86_FEATURE_APIC) && (c->x86<<8 | c->x86_model<<4) == 0x520 &&
 448	    (c->x86_stepping < 0x6 || c->x86_stepping == 0xb))
 449		set_cpu_bug(c, X86_BUG_11AP);
 450
 451
 452#ifdef CONFIG_X86_INTEL_USERCOPY
 453	/*
 454	 * Set up the preferred alignment for movsl bulk memory moves
 455	 */
 456	switch (c->x86) {
 457	case 4:		/* 486: untested */
 458		break;
 459	case 5:		/* Old Pentia: untested */
 460		break;
 461	case 6:		/* PII/PIII only like movsl with 8-byte alignment */
 462		movsl_mask.mask = 7;
 463		break;
 464	case 15:	/* P4 is OK down to 8-byte alignment */
 465		movsl_mask.mask = 7;
 466		break;
 467	}
 468#endif
 469
 
 
 
 
 470	intel_smp_check(c);
 471}
 472#else
 473static void intel_workarounds(struct cpuinfo_x86 *c)
 474{
 475}
 476#endif
 477
 478static void srat_detect_node(struct cpuinfo_x86 *c)
 479{
 480#ifdef CONFIG_NUMA
 481	unsigned node;
 482	int cpu = smp_processor_id();
 483
 484	/* Don't do the funky fallback heuristics the AMD version employs
 485	   for now. */
 486	node = numa_cpu_node(cpu);
 487	if (node == NUMA_NO_NODE || !node_online(node)) {
 488		/* reuse the value from init_cpu_to_node() */
 489		node = cpu_to_node(cpu);
 490	}
 491	numa_set_node(cpu, node);
 492#endif
 493}
 494
 495#define MSR_IA32_TME_ACTIVATE		0x982
 496
 497/* Helpers to access TME_ACTIVATE MSR */
 498#define TME_ACTIVATE_LOCKED(x)		(x & 0x1)
 499#define TME_ACTIVATE_ENABLED(x)		(x & 0x2)
 500
 501#define TME_ACTIVATE_POLICY(x)		((x >> 4) & 0xf)	/* Bits 7:4 */
 502#define TME_ACTIVATE_POLICY_AES_XTS_128	0
 503
 504#define TME_ACTIVATE_KEYID_BITS(x)	((x >> 32) & 0xf)	/* Bits 35:32 */
 505
 506#define TME_ACTIVATE_CRYPTO_ALGS(x)	((x >> 48) & 0xffff)	/* Bits 63:48 */
 507#define TME_ACTIVATE_CRYPTO_AES_XTS_128	1
 508
 509/* Values for mktme_status (SW only construct) */
 510#define MKTME_ENABLED			0
 511#define MKTME_DISABLED			1
 512#define MKTME_UNINITIALIZED		2
 513static int mktme_status = MKTME_UNINITIALIZED;
 514
 515static void detect_tme(struct cpuinfo_x86 *c)
 516{
 517	u64 tme_activate, tme_policy, tme_crypto_algs;
 518	int keyid_bits = 0, nr_keyids = 0;
 519	static u64 tme_activate_cpu0 = 0;
 520
 521	rdmsrl(MSR_IA32_TME_ACTIVATE, tme_activate);
 522
 523	if (mktme_status != MKTME_UNINITIALIZED) {
 524		if (tme_activate != tme_activate_cpu0) {
 525			/* Broken BIOS? */
 526			pr_err_once("x86/tme: configuration is inconsistent between CPUs\n");
 527			pr_err_once("x86/tme: MKTME is not usable\n");
 528			mktme_status = MKTME_DISABLED;
 529
 530			/* Proceed. We may need to exclude bits from x86_phys_bits. */
 531		}
 532	} else {
 533		tme_activate_cpu0 = tme_activate;
 534	}
 535
 536	if (!TME_ACTIVATE_LOCKED(tme_activate) || !TME_ACTIVATE_ENABLED(tme_activate)) {
 537		pr_info_once("x86/tme: not enabled by BIOS\n");
 538		mktme_status = MKTME_DISABLED;
 539		return;
 540	}
 541
 542	if (mktme_status != MKTME_UNINITIALIZED)
 543		goto detect_keyid_bits;
 544
 545	pr_info("x86/tme: enabled by BIOS\n");
 546
 547	tme_policy = TME_ACTIVATE_POLICY(tme_activate);
 548	if (tme_policy != TME_ACTIVATE_POLICY_AES_XTS_128)
 549		pr_warn("x86/tme: Unknown policy is active: %#llx\n", tme_policy);
 550
 551	tme_crypto_algs = TME_ACTIVATE_CRYPTO_ALGS(tme_activate);
 552	if (!(tme_crypto_algs & TME_ACTIVATE_CRYPTO_AES_XTS_128)) {
 553		pr_err("x86/mktme: No known encryption algorithm is supported: %#llx\n",
 554				tme_crypto_algs);
 555		mktme_status = MKTME_DISABLED;
 556	}
 557detect_keyid_bits:
 558	keyid_bits = TME_ACTIVATE_KEYID_BITS(tme_activate);
 559	nr_keyids = (1UL << keyid_bits) - 1;
 560	if (nr_keyids) {
 561		pr_info_once("x86/mktme: enabled by BIOS\n");
 562		pr_info_once("x86/mktme: %d KeyIDs available\n", nr_keyids);
 563	} else {
 564		pr_info_once("x86/mktme: disabled by BIOS\n");
 565	}
 566
 567	if (mktme_status == MKTME_UNINITIALIZED) {
 568		/* MKTME is usable */
 569		mktme_status = MKTME_ENABLED;
 570	}
 571
 572	/*
 573	 * KeyID bits effectively lower the number of physical address
 574	 * bits.  Update cpuinfo_x86::x86_phys_bits accordingly.
 575	 */
 576	c->x86_phys_bits -= keyid_bits;
 577}
 578
 579static void init_cpuid_fault(struct cpuinfo_x86 *c)
 580{
 581	u64 msr;
 582
 583	if (!rdmsrl_safe(MSR_PLATFORM_INFO, &msr)) {
 584		if (msr & MSR_PLATFORM_INFO_CPUID_FAULT)
 585			set_cpu_cap(c, X86_FEATURE_CPUID_FAULT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 586	}
 587}
 588
 589static void init_intel_misc_features(struct cpuinfo_x86 *c)
 590{
 591	u64 msr;
 592
 593	if (rdmsrl_safe(MSR_MISC_FEATURES_ENABLES, &msr))
 594		return;
 595
 596	/* Clear all MISC features */
 597	this_cpu_write(msr_misc_features_shadow, 0);
 598
 599	/* Check features and update capabilities and shadow control bits */
 600	init_cpuid_fault(c);
 601	probe_xeon_phi_r3mwait(c);
 602
 603	msr = this_cpu_read(msr_misc_features_shadow);
 604	wrmsrl(MSR_MISC_FEATURES_ENABLES, msr);
 605}
 606
 607static void split_lock_init(void);
 608static void bus_lock_init(void);
 609
 610static void init_intel(struct cpuinfo_x86 *c)
 611{
 612	early_init_intel(c);
 613
 614	intel_workarounds(c);
 615
 616	/*
 617	 * Detect the extended topology information if available. This
 618	 * will reinitialise the initial_apicid which will be used
 619	 * in init_intel_cacheinfo()
 620	 */
 621	detect_extended_topology(c);
 622
 623	if (!cpu_has(c, X86_FEATURE_XTOPOLOGY)) {
 624		/*
 625		 * let's use the legacy cpuid vector 0x1 and 0x4 for topology
 626		 * detection.
 627		 */
 628		detect_num_cpu_cores(c);
 629#ifdef CONFIG_X86_32
 630		detect_ht(c);
 631#endif
 632	}
 633
 634	init_intel_cacheinfo(c);
 635
 636	if (c->cpuid_level > 9) {
 637		unsigned eax = cpuid_eax(10);
 638		/* Check for version and the number of counters */
 639		if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
 640			set_cpu_cap(c, X86_FEATURE_ARCH_PERFMON);
 641	}
 642
 643	if (cpu_has(c, X86_FEATURE_XMM2))
 644		set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC);
 645
 646	if (boot_cpu_has(X86_FEATURE_DS)) {
 647		unsigned int l1, l2;
 648
 649		rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
 650		if (!(l1 & (1<<11)))
 651			set_cpu_cap(c, X86_FEATURE_BTS);
 652		if (!(l1 & (1<<12)))
 653			set_cpu_cap(c, X86_FEATURE_PEBS);
 654	}
 655
 656	if (c->x86 == 6 && boot_cpu_has(X86_FEATURE_CLFLUSH) &&
 657	    (c->x86_model == 29 || c->x86_model == 46 || c->x86_model == 47))
 658		set_cpu_bug(c, X86_BUG_CLFLUSH_MONITOR);
 659
 660	if (c->x86 == 6 && boot_cpu_has(X86_FEATURE_MWAIT) &&
 661		((c->x86_model == INTEL_FAM6_ATOM_GOLDMONT)))
 662		set_cpu_bug(c, X86_BUG_MONITOR);
 663
 664#ifdef CONFIG_X86_64
 665	if (c->x86 == 15)
 666		c->x86_cache_alignment = c->x86_clflush_size * 2;
 667	if (c->x86 == 6)
 668		set_cpu_cap(c, X86_FEATURE_REP_GOOD);
 669#else
 670	/*
 671	 * Names for the Pentium II/Celeron processors
 672	 * detectable only by also checking the cache size.
 673	 * Dixon is NOT a Celeron.
 674	 */
 675	if (c->x86 == 6) {
 676		unsigned int l2 = c->x86_cache_size;
 677		char *p = NULL;
 678
 679		switch (c->x86_model) {
 680		case 5:
 681			if (l2 == 0)
 682				p = "Celeron (Covington)";
 683			else if (l2 == 256)
 684				p = "Mobile Pentium II (Dixon)";
 685			break;
 686
 687		case 6:
 688			if (l2 == 128)
 689				p = "Celeron (Mendocino)";
 690			else if (c->x86_stepping == 0 || c->x86_stepping == 5)
 691				p = "Celeron-A";
 692			break;
 693
 694		case 8:
 695			if (l2 == 128)
 696				p = "Celeron (Coppermine)";
 697			break;
 698		}
 699
 700		if (p)
 701			strcpy(c->x86_model_id, p);
 702	}
 703
 704	if (c->x86 == 15)
 705		set_cpu_cap(c, X86_FEATURE_P4);
 706	if (c->x86 == 6)
 707		set_cpu_cap(c, X86_FEATURE_P3);
 708#endif
 709
 
 
 
 
 
 
 
 
 
 
 
 710	/* Work around errata */
 711	srat_detect_node(c);
 712
 713	init_ia32_feat_ctl(c);
 
 714
 715	if (cpu_has(c, X86_FEATURE_TME))
 716		detect_tme(c);
 717
 718	init_intel_misc_features(c);
 719
 720	if (tsx_ctrl_state == TSX_CTRL_ENABLE)
 721		tsx_enable();
 722	else if (tsx_ctrl_state == TSX_CTRL_DISABLE)
 723		tsx_disable();
 724	else if (tsx_ctrl_state == TSX_CTRL_RTM_ALWAYS_ABORT)
 725		tsx_clear_cpuid();
 726
 727	split_lock_init();
 728	bus_lock_init();
 729
 730	intel_init_thermal(c);
 
 731}
 732
 733#ifdef CONFIG_X86_32
 734static unsigned int intel_size_cache(struct cpuinfo_x86 *c, unsigned int size)
 735{
 736	/*
 737	 * Intel PIII Tualatin. This comes in two flavours.
 738	 * One has 256kb of cache, the other 512. We have no way
 739	 * to determine which, so we use a boottime override
 740	 * for the 512kb model, and assume 256 otherwise.
 741	 */
 742	if ((c->x86 == 6) && (c->x86_model == 11) && (size == 0))
 743		size = 256;
 744
 745	/*
 746	 * Intel Quark SoC X1000 contains a 4-way set associative
 747	 * 16K cache with a 16 byte cache line and 256 lines per tag
 748	 */
 749	if ((c->x86 == 5) && (c->x86_model == 9))
 750		size = 16;
 751	return size;
 752}
 753#endif
 754
 755#define TLB_INST_4K	0x01
 756#define TLB_INST_4M	0x02
 757#define TLB_INST_2M_4M	0x03
 758
 759#define TLB_INST_ALL	0x05
 760#define TLB_INST_1G	0x06
 761
 762#define TLB_DATA_4K	0x11
 763#define TLB_DATA_4M	0x12
 764#define TLB_DATA_2M_4M	0x13
 765#define TLB_DATA_4K_4M	0x14
 766
 767#define TLB_DATA_1G	0x16
 768
 769#define TLB_DATA0_4K	0x21
 770#define TLB_DATA0_4M	0x22
 771#define TLB_DATA0_2M_4M	0x23
 772
 773#define STLB_4K		0x41
 774#define STLB_4K_2M	0x42
 775
 776static const struct _tlb_table intel_tlb_table[] = {
 777	{ 0x01, TLB_INST_4K,		32,	" TLB_INST 4 KByte pages, 4-way set associative" },
 778	{ 0x02, TLB_INST_4M,		2,	" TLB_INST 4 MByte pages, full associative" },
 779	{ 0x03, TLB_DATA_4K,		64,	" TLB_DATA 4 KByte pages, 4-way set associative" },
 780	{ 0x04, TLB_DATA_4M,		8,	" TLB_DATA 4 MByte pages, 4-way set associative" },
 781	{ 0x05, TLB_DATA_4M,		32,	" TLB_DATA 4 MByte pages, 4-way set associative" },
 782	{ 0x0b, TLB_INST_4M,		4,	" TLB_INST 4 MByte pages, 4-way set associative" },
 783	{ 0x4f, TLB_INST_4K,		32,	" TLB_INST 4 KByte pages" },
 784	{ 0x50, TLB_INST_ALL,		64,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
 785	{ 0x51, TLB_INST_ALL,		128,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
 786	{ 0x52, TLB_INST_ALL,		256,	" TLB_INST 4 KByte and 2-MByte or 4-MByte pages" },
 787	{ 0x55, TLB_INST_2M_4M,		7,	" TLB_INST 2-MByte or 4-MByte pages, fully associative" },
 788	{ 0x56, TLB_DATA0_4M,		16,	" TLB_DATA0 4 MByte pages, 4-way set associative" },
 789	{ 0x57, TLB_DATA0_4K,		16,	" TLB_DATA0 4 KByte pages, 4-way associative" },
 790	{ 0x59, TLB_DATA0_4K,		16,	" TLB_DATA0 4 KByte pages, fully associative" },
 791	{ 0x5a, TLB_DATA0_2M_4M,	32,	" TLB_DATA0 2-MByte or 4 MByte pages, 4-way set associative" },
 792	{ 0x5b, TLB_DATA_4K_4M,		64,	" TLB_DATA 4 KByte and 4 MByte pages" },
 793	{ 0x5c, TLB_DATA_4K_4M,		128,	" TLB_DATA 4 KByte and 4 MByte pages" },
 794	{ 0x5d, TLB_DATA_4K_4M,		256,	" TLB_DATA 4 KByte and 4 MByte pages" },
 795	{ 0x61, TLB_INST_4K,		48,	" TLB_INST 4 KByte pages, full associative" },
 796	{ 0x63, TLB_DATA_1G,		4,	" TLB_DATA 1 GByte pages, 4-way set associative" },
 797	{ 0x6b, TLB_DATA_4K,		256,	" TLB_DATA 4 KByte pages, 8-way associative" },
 798	{ 0x6c, TLB_DATA_2M_4M,		128,	" TLB_DATA 2 MByte or 4 MByte pages, 8-way associative" },
 799	{ 0x6d, TLB_DATA_1G,		16,	" TLB_DATA 1 GByte pages, fully associative" },
 800	{ 0x76, TLB_INST_2M_4M,		8,	" TLB_INST 2-MByte or 4-MByte pages, fully associative" },
 801	{ 0xb0, TLB_INST_4K,		128,	" TLB_INST 4 KByte pages, 4-way set associative" },
 802	{ 0xb1, TLB_INST_2M_4M,		4,	" TLB_INST 2M pages, 4-way, 8 entries or 4M pages, 4-way entries" },
 803	{ 0xb2, TLB_INST_4K,		64,	" TLB_INST 4KByte pages, 4-way set associative" },
 804	{ 0xb3, TLB_DATA_4K,		128,	" TLB_DATA 4 KByte pages, 4-way set associative" },
 805	{ 0xb4, TLB_DATA_4K,		256,	" TLB_DATA 4 KByte pages, 4-way associative" },
 806	{ 0xb5, TLB_INST_4K,		64,	" TLB_INST 4 KByte pages, 8-way set associative" },
 807	{ 0xb6, TLB_INST_4K,		128,	" TLB_INST 4 KByte pages, 8-way set associative" },
 808	{ 0xba, TLB_DATA_4K,		64,	" TLB_DATA 4 KByte pages, 4-way associative" },
 809	{ 0xc0, TLB_DATA_4K_4M,		8,	" TLB_DATA 4 KByte and 4 MByte pages, 4-way associative" },
 810	{ 0xc1, STLB_4K_2M,		1024,	" STLB 4 KByte and 2 MByte pages, 8-way associative" },
 811	{ 0xc2, TLB_DATA_2M_4M,		16,	" TLB_DATA 2 MByte/4MByte pages, 4-way associative" },
 812	{ 0xca, STLB_4K,		512,	" STLB 4 KByte pages, 4-way associative" },
 813	{ 0x00, 0, 0 }
 814};
 815
 816static void intel_tlb_lookup(const unsigned char desc)
 817{
 818	unsigned char k;
 819	if (desc == 0)
 820		return;
 821
 822	/* look up this descriptor in the table */
 823	for (k = 0; intel_tlb_table[k].descriptor != desc &&
 824	     intel_tlb_table[k].descriptor != 0; k++)
 825		;
 826
 827	if (intel_tlb_table[k].tlb_type == 0)
 828		return;
 829
 830	switch (intel_tlb_table[k].tlb_type) {
 831	case STLB_4K:
 832		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 833			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 834		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 835			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 836		break;
 837	case STLB_4K_2M:
 838		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 839			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 840		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 841			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 842		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
 843			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
 844		if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries)
 845			tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries;
 846		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 847			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 848		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 849			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 850		break;
 851	case TLB_INST_ALL:
 852		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 853			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 854		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
 855			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
 856		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 857			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 858		break;
 859	case TLB_INST_4K:
 860		if (tlb_lli_4k[ENTRIES] < intel_tlb_table[k].entries)
 861			tlb_lli_4k[ENTRIES] = intel_tlb_table[k].entries;
 862		break;
 863	case TLB_INST_4M:
 864		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 865			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 866		break;
 867	case TLB_INST_2M_4M:
 868		if (tlb_lli_2m[ENTRIES] < intel_tlb_table[k].entries)
 869			tlb_lli_2m[ENTRIES] = intel_tlb_table[k].entries;
 870		if (tlb_lli_4m[ENTRIES] < intel_tlb_table[k].entries)
 871			tlb_lli_4m[ENTRIES] = intel_tlb_table[k].entries;
 872		break;
 873	case TLB_DATA_4K:
 874	case TLB_DATA0_4K:
 875		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 876			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 877		break;
 878	case TLB_DATA_4M:
 879	case TLB_DATA0_4M:
 880		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 881			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 882		break;
 883	case TLB_DATA_2M_4M:
 884	case TLB_DATA0_2M_4M:
 885		if (tlb_lld_2m[ENTRIES] < intel_tlb_table[k].entries)
 886			tlb_lld_2m[ENTRIES] = intel_tlb_table[k].entries;
 887		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 888			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 889		break;
 890	case TLB_DATA_4K_4M:
 891		if (tlb_lld_4k[ENTRIES] < intel_tlb_table[k].entries)
 892			tlb_lld_4k[ENTRIES] = intel_tlb_table[k].entries;
 893		if (tlb_lld_4m[ENTRIES] < intel_tlb_table[k].entries)
 894			tlb_lld_4m[ENTRIES] = intel_tlb_table[k].entries;
 895		break;
 896	case TLB_DATA_1G:
 897		if (tlb_lld_1g[ENTRIES] < intel_tlb_table[k].entries)
 898			tlb_lld_1g[ENTRIES] = intel_tlb_table[k].entries;
 899		break;
 900	}
 901}
 902
 903static void intel_detect_tlb(struct cpuinfo_x86 *c)
 904{
 905	int i, j, n;
 906	unsigned int regs[4];
 907	unsigned char *desc = (unsigned char *)regs;
 908
 909	if (c->cpuid_level < 2)
 910		return;
 911
 912	/* Number of times to iterate */
 913	n = cpuid_eax(2) & 0xFF;
 914
 915	for (i = 0 ; i < n ; i++) {
 916		cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
 917
 918		/* If bit 31 is set, this is an unknown format */
 919		for (j = 0 ; j < 3 ; j++)
 920			if (regs[j] & (1 << 31))
 921				regs[j] = 0;
 922
 923		/* Byte 0 is level count, not a descriptor */
 924		for (j = 1 ; j < 16 ; j++)
 925			intel_tlb_lookup(desc[j]);
 926	}
 927}
 928
 929static const struct cpu_dev intel_cpu_dev = {
 930	.c_vendor	= "Intel",
 931	.c_ident	= { "GenuineIntel" },
 932#ifdef CONFIG_X86_32
 933	.legacy_models = {
 934		{ .family = 4, .model_names =
 935		  {
 936			  [0] = "486 DX-25/33",
 937			  [1] = "486 DX-50",
 938			  [2] = "486 SX",
 939			  [3] = "486 DX/2",
 940			  [4] = "486 SL",
 941			  [5] = "486 SX/2",
 942			  [7] = "486 DX/2-WB",
 943			  [8] = "486 DX/4",
 944			  [9] = "486 DX/4-WB"
 945		  }
 946		},
 947		{ .family = 5, .model_names =
 948		  {
 949			  [0] = "Pentium 60/66 A-step",
 950			  [1] = "Pentium 60/66",
 951			  [2] = "Pentium 75 - 200",
 952			  [3] = "OverDrive PODP5V83",
 953			  [4] = "Pentium MMX",
 954			  [7] = "Mobile Pentium 75 - 200",
 955			  [8] = "Mobile Pentium MMX",
 956			  [9] = "Quark SoC X1000",
 957		  }
 958		},
 959		{ .family = 6, .model_names =
 960		  {
 961			  [0] = "Pentium Pro A-step",
 962			  [1] = "Pentium Pro",
 963			  [3] = "Pentium II (Klamath)",
 964			  [4] = "Pentium II (Deschutes)",
 965			  [5] = "Pentium II (Deschutes)",
 966			  [6] = "Mobile Pentium II",
 967			  [7] = "Pentium III (Katmai)",
 968			  [8] = "Pentium III (Coppermine)",
 969			  [10] = "Pentium III (Cascades)",
 970			  [11] = "Pentium III (Tualatin)",
 971		  }
 972		},
 973		{ .family = 15, .model_names =
 974		  {
 975			  [0] = "Pentium 4 (Unknown)",
 976			  [1] = "Pentium 4 (Willamette)",
 977			  [2] = "Pentium 4 (Northwood)",
 978			  [4] = "Pentium 4 (Foster)",
 979			  [5] = "Pentium 4 (Foster)",
 980		  }
 981		},
 982	},
 983	.legacy_cache_size = intel_size_cache,
 984#endif
 985	.c_detect_tlb	= intel_detect_tlb,
 986	.c_early_init   = early_init_intel,
 987	.c_bsp_init	= bsp_init_intel,
 988	.c_init		= init_intel,
 989	.c_x86_vendor	= X86_VENDOR_INTEL,
 990};
 991
 992cpu_dev_register(intel_cpu_dev);
 993
 994#undef pr_fmt
 995#define pr_fmt(fmt) "x86/split lock detection: " fmt
 996
 997static const struct {
 998	const char			*option;
 999	enum split_lock_detect_state	state;
1000} sld_options[] __initconst = {
1001	{ "off",	sld_off   },
1002	{ "warn",	sld_warn  },
1003	{ "fatal",	sld_fatal },
1004	{ "ratelimit:", sld_ratelimit },
1005};
1006
1007static struct ratelimit_state bld_ratelimit;
1008
1009static inline bool match_option(const char *arg, int arglen, const char *opt)
1010{
1011	int len = strlen(opt), ratelimit;
1012
1013	if (strncmp(arg, opt, len))
1014		return false;
1015
1016	/*
1017	 * Min ratelimit is 1 bus lock/sec.
1018	 * Max ratelimit is 1000 bus locks/sec.
1019	 */
1020	if (sscanf(arg, "ratelimit:%d", &ratelimit) == 1 &&
1021	    ratelimit > 0 && ratelimit <= 1000) {
1022		ratelimit_state_init(&bld_ratelimit, HZ, ratelimit);
1023		ratelimit_set_flags(&bld_ratelimit, RATELIMIT_MSG_ON_RELEASE);
1024		return true;
1025	}
1026
1027	return len == arglen;
1028}
1029
1030static bool split_lock_verify_msr(bool on)
1031{
1032	u64 ctrl, tmp;
1033
1034	if (rdmsrl_safe(MSR_TEST_CTRL, &ctrl))
1035		return false;
1036	if (on)
1037		ctrl |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
1038	else
1039		ctrl &= ~MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
1040	if (wrmsrl_safe(MSR_TEST_CTRL, ctrl))
1041		return false;
1042	rdmsrl(MSR_TEST_CTRL, tmp);
1043	return ctrl == tmp;
1044}
1045
1046static void __init sld_state_setup(void)
1047{
1048	enum split_lock_detect_state state = sld_warn;
1049	char arg[20];
1050	int i, ret;
1051
1052	if (!boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) &&
1053	    !boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT))
1054		return;
1055
1056	ret = cmdline_find_option(boot_command_line, "split_lock_detect",
1057				  arg, sizeof(arg));
1058	if (ret >= 0) {
1059		for (i = 0; i < ARRAY_SIZE(sld_options); i++) {
1060			if (match_option(arg, ret, sld_options[i].option)) {
1061				state = sld_options[i].state;
1062				break;
1063			}
1064		}
1065	}
1066	sld_state = state;
1067}
1068
1069static void __init __split_lock_setup(void)
1070{
1071	if (!split_lock_verify_msr(false)) {
1072		pr_info("MSR access failed: Disabled\n");
1073		return;
1074	}
1075
1076	rdmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache);
1077
1078	if (!split_lock_verify_msr(true)) {
1079		pr_info("MSR access failed: Disabled\n");
1080		return;
1081	}
1082
1083	/* Restore the MSR to its cached value. */
1084	wrmsrl(MSR_TEST_CTRL, msr_test_ctrl_cache);
1085
1086	setup_force_cpu_cap(X86_FEATURE_SPLIT_LOCK_DETECT);
1087}
1088
1089/*
1090 * MSR_TEST_CTRL is per core, but we treat it like a per CPU MSR. Locking
1091 * is not implemented as one thread could undo the setting of the other
1092 * thread immediately after dropping the lock anyway.
1093 */
1094static void sld_update_msr(bool on)
1095{
1096	u64 test_ctrl_val = msr_test_ctrl_cache;
1097
1098	if (on)
1099		test_ctrl_val |= MSR_TEST_CTRL_SPLIT_LOCK_DETECT;
1100
1101	wrmsrl(MSR_TEST_CTRL, test_ctrl_val);
1102}
1103
1104static void split_lock_init(void)
1105{
1106	/*
1107	 * #DB for bus lock handles ratelimit and #AC for split lock is
1108	 * disabled.
1109	 */
1110	if (sld_state == sld_ratelimit) {
1111		split_lock_verify_msr(false);
1112		return;
1113	}
1114
1115	if (cpu_model_supports_sld)
1116		split_lock_verify_msr(sld_state != sld_off);
1117}
1118
1119static void split_lock_warn(unsigned long ip)
1120{
1121	pr_warn_ratelimited("#AC: %s/%d took a split_lock trap at address: 0x%lx\n",
1122			    current->comm, current->pid, ip);
1123
1124	/*
1125	 * Disable the split lock detection for this task so it can make
1126	 * progress and set TIF_SLD so the detection is re-enabled via
1127	 * switch_to_sld() when the task is scheduled out.
1128	 */
1129	sld_update_msr(false);
1130	set_tsk_thread_flag(current, TIF_SLD);
1131}
1132
1133bool handle_guest_split_lock(unsigned long ip)
1134{
1135	if (sld_state == sld_warn) {
1136		split_lock_warn(ip);
1137		return true;
1138	}
1139
1140	pr_warn_once("#AC: %s/%d %s split_lock trap at address: 0x%lx\n",
1141		     current->comm, current->pid,
1142		     sld_state == sld_fatal ? "fatal" : "bogus", ip);
1143
1144	current->thread.error_code = 0;
1145	current->thread.trap_nr = X86_TRAP_AC;
1146	force_sig_fault(SIGBUS, BUS_ADRALN, NULL);
1147	return false;
1148}
1149EXPORT_SYMBOL_GPL(handle_guest_split_lock);
1150
1151static void bus_lock_init(void)
1152{
1153	u64 val;
1154
1155	/*
1156	 * Warn and fatal are handled by #AC for split lock if #AC for
1157	 * split lock is supported.
1158	 */
1159	if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT) ||
1160	    (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) &&
1161	    (sld_state == sld_warn || sld_state == sld_fatal)) ||
1162	    sld_state == sld_off)
1163		return;
1164
1165	/*
1166	 * Enable #DB for bus lock. All bus locks are handled in #DB except
1167	 * split locks are handled in #AC in the fatal case.
1168	 */
1169	rdmsrl(MSR_IA32_DEBUGCTLMSR, val);
1170	val |= DEBUGCTLMSR_BUS_LOCK_DETECT;
1171	wrmsrl(MSR_IA32_DEBUGCTLMSR, val);
1172}
1173
1174bool handle_user_split_lock(struct pt_regs *regs, long error_code)
1175{
1176	if ((regs->flags & X86_EFLAGS_AC) || sld_state == sld_fatal)
1177		return false;
1178	split_lock_warn(regs->ip);
1179	return true;
1180}
1181
1182void handle_bus_lock(struct pt_regs *regs)
1183{
1184	switch (sld_state) {
1185	case sld_off:
1186		break;
1187	case sld_ratelimit:
1188		/* Enforce no more than bld_ratelimit bus locks/sec. */
1189		while (!__ratelimit(&bld_ratelimit))
1190			msleep(20);
1191		/* Warn on the bus lock. */
1192		fallthrough;
1193	case sld_warn:
1194		pr_warn_ratelimited("#DB: %s/%d took a bus_lock trap at address: 0x%lx\n",
1195				    current->comm, current->pid, regs->ip);
1196		break;
1197	case sld_fatal:
1198		force_sig_fault(SIGBUS, BUS_ADRALN, NULL);
1199		break;
1200	}
1201}
1202
1203/*
1204 * This function is called only when switching between tasks with
1205 * different split-lock detection modes. It sets the MSR for the
1206 * mode of the new task. This is right most of the time, but since
1207 * the MSR is shared by hyperthreads on a physical core there can
1208 * be glitches when the two threads need different modes.
1209 */
1210void switch_to_sld(unsigned long tifn)
1211{
1212	sld_update_msr(!(tifn & _TIF_SLD));
1213}
1214
1215/*
1216 * Bits in the IA32_CORE_CAPABILITIES are not architectural, so they should
1217 * only be trusted if it is confirmed that a CPU model implements a
1218 * specific feature at a particular bit position.
1219 *
1220 * The possible driver data field values:
1221 *
1222 * - 0: CPU models that are known to have the per-core split-lock detection
1223 *	feature even though they do not enumerate IA32_CORE_CAPABILITIES.
1224 *
1225 * - 1: CPU models which may enumerate IA32_CORE_CAPABILITIES and if so use
1226 *      bit 5 to enumerate the per-core split-lock detection feature.
1227 */
1228static const struct x86_cpu_id split_lock_cpu_ids[] __initconst = {
1229	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_X,		0),
1230	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_L,		0),
1231	X86_MATCH_INTEL_FAM6_MODEL(ICELAKE_D,		0),
1232	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT,	1),
1233	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_D,	1),
1234	X86_MATCH_INTEL_FAM6_MODEL(ATOM_TREMONT_L,	1),
1235	X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE_L,		1),
1236	X86_MATCH_INTEL_FAM6_MODEL(TIGERLAKE,		1),
1237	X86_MATCH_INTEL_FAM6_MODEL(SAPPHIRERAPIDS_X,	1),
1238	X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE,		1),
1239	X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L,		1),
1240	{}
1241};
1242
1243static void __init split_lock_setup(struct cpuinfo_x86 *c)
1244{
1245	const struct x86_cpu_id *m;
1246	u64 ia32_core_caps;
1247
1248	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
1249		return;
1250
1251	m = x86_match_cpu(split_lock_cpu_ids);
1252	if (!m)
1253		return;
1254
1255	switch (m->driver_data) {
1256	case 0:
1257		break;
1258	case 1:
1259		if (!cpu_has(c, X86_FEATURE_CORE_CAPABILITIES))
1260			return;
1261		rdmsrl(MSR_IA32_CORE_CAPS, ia32_core_caps);
1262		if (!(ia32_core_caps & MSR_IA32_CORE_CAPS_SPLIT_LOCK_DETECT))
1263			return;
1264		break;
1265	default:
1266		return;
1267	}
1268
1269	cpu_model_supports_sld = true;
1270	__split_lock_setup();
1271}
1272
1273static void sld_state_show(void)
1274{
1275	if (!boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT) &&
1276	    !boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
1277		return;
1278
1279	switch (sld_state) {
1280	case sld_off:
1281		pr_info("disabled\n");
1282		break;
1283	case sld_warn:
1284		if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT))
1285			pr_info("#AC: crashing the kernel on kernel split_locks and warning on user-space split_locks\n");
1286		else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT))
1287			pr_info("#DB: warning on user-space bus_locks\n");
1288		break;
1289	case sld_fatal:
1290		if (boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT)) {
1291			pr_info("#AC: crashing the kernel on kernel split_locks and sending SIGBUS on user-space split_locks\n");
1292		} else if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT)) {
1293			pr_info("#DB: sending SIGBUS on user-space bus_locks%s\n",
1294				boot_cpu_has(X86_FEATURE_SPLIT_LOCK_DETECT) ?
1295				" from non-WB" : "");
1296		}
1297		break;
1298	case sld_ratelimit:
1299		if (boot_cpu_has(X86_FEATURE_BUS_LOCK_DETECT))
1300			pr_info("#DB: setting system wide bus lock rate limit to %u/sec\n", bld_ratelimit.burst);
1301		break;
1302	}
1303}
1304
1305void __init sld_setup(struct cpuinfo_x86 *c)
1306{
1307	split_lock_setup(c);
1308	sld_state_setup();
1309	sld_state_show();
1310}
1311
1312#define X86_HYBRID_CPU_TYPE_ID_SHIFT	24
1313
1314/**
1315 * get_this_hybrid_cpu_type() - Get the type of this hybrid CPU
1316 *
1317 * Returns the CPU type [31:24] (i.e., Atom or Core) of a CPU in
1318 * a hybrid processor. If the processor is not hybrid, returns 0.
1319 */
1320u8 get_this_hybrid_cpu_type(void)
1321{
1322	if (!cpu_feature_enabled(X86_FEATURE_HYBRID_CPU))
1323		return 0;
1324
1325	return cpuid_eax(0x0000001a) >> X86_HYBRID_CPU_TYPE_ID_SHIFT;
1326}