xref: /openbmc/linux/arch/x86/include/asm/processor.h (revision ed84ef1c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_PROCESSOR_H
3 #define _ASM_X86_PROCESSOR_H
4 
5 #include <asm/processor-flags.h>
6 
7 /* Forward declaration, a strange C thing */
8 struct task_struct;
9 struct mm_struct;
10 struct io_bitmap;
11 struct vm86;
12 
13 #include <asm/math_emu.h>
14 #include <asm/segment.h>
15 #include <asm/types.h>
16 #include <uapi/asm/sigcontext.h>
17 #include <asm/current.h>
18 #include <asm/cpufeatures.h>
19 #include <asm/page.h>
20 #include <asm/pgtable_types.h>
21 #include <asm/percpu.h>
22 #include <asm/msr.h>
23 #include <asm/desc_defs.h>
24 #include <asm/nops.h>
25 #include <asm/special_insns.h>
26 #include <asm/fpu/types.h>
27 #include <asm/unwind_hints.h>
28 #include <asm/vmxfeatures.h>
29 #include <asm/vdso/processor.h>
30 
31 #include <linux/personality.h>
32 #include <linux/cache.h>
33 #include <linux/threads.h>
34 #include <linux/math64.h>
35 #include <linux/err.h>
36 #include <linux/irqflags.h>
37 #include <linux/mem_encrypt.h>
38 
39 /*
40  * We handle most unaligned accesses in hardware.  On the other hand
41  * unaligned DMA can be quite expensive on some Nehalem processors.
42  *
43  * Based on this we disable the IP header alignment in network drivers.
44  */
45 #define NET_IP_ALIGN	0
46 
47 #define HBP_NUM 4
48 
49 /*
50  * These alignment constraints are for performance in the vSMP case,
51  * but in the task_struct case we must also meet hardware imposed
52  * alignment requirements of the FPU state:
53  */
54 #ifdef CONFIG_X86_VSMP
55 # define ARCH_MIN_TASKALIGN		(1 << INTERNODE_CACHE_SHIFT)
56 # define ARCH_MIN_MMSTRUCT_ALIGN	(1 << INTERNODE_CACHE_SHIFT)
57 #else
58 # define ARCH_MIN_TASKALIGN		__alignof__(union fpregs_state)
59 # define ARCH_MIN_MMSTRUCT_ALIGN	0
60 #endif
61 
62 enum tlb_infos {
63 	ENTRIES,
64 	NR_INFO
65 };
66 
67 extern u16 __read_mostly tlb_lli_4k[NR_INFO];
68 extern u16 __read_mostly tlb_lli_2m[NR_INFO];
69 extern u16 __read_mostly tlb_lli_4m[NR_INFO];
70 extern u16 __read_mostly tlb_lld_4k[NR_INFO];
71 extern u16 __read_mostly tlb_lld_2m[NR_INFO];
72 extern u16 __read_mostly tlb_lld_4m[NR_INFO];
73 extern u16 __read_mostly tlb_lld_1g[NR_INFO];
74 
75 /*
76  *  CPU type and hardware bug flags. Kept separately for each CPU.
77  *  Members of this structure are referenced in head_32.S, so think twice
78  *  before touching them. [mj]
79  */
80 
81 struct cpuinfo_x86 {
82 	__u8			x86;		/* CPU family */
83 	__u8			x86_vendor;	/* CPU vendor */
84 	__u8			x86_model;
85 	__u8			x86_stepping;
86 #ifdef CONFIG_X86_64
87 	/* Number of 4K pages in DTLB/ITLB combined(in pages): */
88 	int			x86_tlbsize;
89 #endif
90 #ifdef CONFIG_X86_VMX_FEATURE_NAMES
91 	__u32			vmx_capability[NVMXINTS];
92 #endif
93 	__u8			x86_virt_bits;
94 	__u8			x86_phys_bits;
95 	/* CPUID returned core id bits: */
96 	__u8			x86_coreid_bits;
97 	__u8			cu_id;
98 	/* Max extended CPUID function supported: */
99 	__u32			extended_cpuid_level;
100 	/* Maximum supported CPUID level, -1=no CPUID: */
101 	int			cpuid_level;
102 	/*
103 	 * Align to size of unsigned long because the x86_capability array
104 	 * is passed to bitops which require the alignment. Use unnamed
105 	 * union to enforce the array is aligned to size of unsigned long.
106 	 */
107 	union {
108 		__u32		x86_capability[NCAPINTS + NBUGINTS];
109 		unsigned long	x86_capability_alignment;
110 	};
111 	char			x86_vendor_id[16];
112 	char			x86_model_id[64];
113 	/* in KB - valid for CPUS which support this call: */
114 	unsigned int		x86_cache_size;
115 	int			x86_cache_alignment;	/* In bytes */
116 	/* Cache QoS architectural values, valid only on the BSP: */
117 	int			x86_cache_max_rmid;	/* max index */
118 	int			x86_cache_occ_scale;	/* scale to bytes */
119 	int			x86_cache_mbm_width_offset;
120 	int			x86_power;
121 	unsigned long		loops_per_jiffy;
122 	/* cpuid returned max cores value: */
123 	u16			x86_max_cores;
124 	u16			apicid;
125 	u16			initial_apicid;
126 	u16			x86_clflush_size;
127 	/* number of cores as seen by the OS: */
128 	u16			booted_cores;
129 	/* Physical processor id: */
130 	u16			phys_proc_id;
131 	/* Logical processor id: */
132 	u16			logical_proc_id;
133 	/* Core id: */
134 	u16			cpu_core_id;
135 	u16			cpu_die_id;
136 	u16			logical_die_id;
137 	/* Index into per_cpu list: */
138 	u16			cpu_index;
139 	/*  Is SMT active on this core? */
140 	bool			smt_active;
141 	u32			microcode;
142 	/* Address space bits used by the cache internally */
143 	u8			x86_cache_bits;
144 	unsigned		initialized : 1;
145 } __randomize_layout;
146 
147 struct cpuid_regs {
148 	u32 eax, ebx, ecx, edx;
149 };
150 
151 enum cpuid_regs_idx {
152 	CPUID_EAX = 0,
153 	CPUID_EBX,
154 	CPUID_ECX,
155 	CPUID_EDX,
156 };
157 
158 #define X86_VENDOR_INTEL	0
159 #define X86_VENDOR_CYRIX	1
160 #define X86_VENDOR_AMD		2
161 #define X86_VENDOR_UMC		3
162 #define X86_VENDOR_CENTAUR	5
163 #define X86_VENDOR_TRANSMETA	7
164 #define X86_VENDOR_NSC		8
165 #define X86_VENDOR_HYGON	9
166 #define X86_VENDOR_ZHAOXIN	10
167 #define X86_VENDOR_NUM		11
168 
169 #define X86_VENDOR_UNKNOWN	0xff
170 
171 /*
172  * capabilities of CPUs
173  */
174 extern struct cpuinfo_x86	boot_cpu_data;
175 extern struct cpuinfo_x86	new_cpu_data;
176 
177 extern __u32			cpu_caps_cleared[NCAPINTS + NBUGINTS];
178 extern __u32			cpu_caps_set[NCAPINTS + NBUGINTS];
179 
180 #ifdef CONFIG_SMP
181 DECLARE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
182 #define cpu_data(cpu)		per_cpu(cpu_info, cpu)
183 #else
184 #define cpu_info		boot_cpu_data
185 #define cpu_data(cpu)		boot_cpu_data
186 #endif
187 
188 extern const struct seq_operations cpuinfo_op;
189 
190 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
191 
192 extern void cpu_detect(struct cpuinfo_x86 *c);
193 
194 static inline unsigned long long l1tf_pfn_limit(void)
195 {
196 	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
197 }
198 
199 extern void early_cpu_init(void);
200 extern void identify_boot_cpu(void);
201 extern void identify_secondary_cpu(struct cpuinfo_x86 *);
202 extern void print_cpu_info(struct cpuinfo_x86 *);
203 void print_cpu_msr(struct cpuinfo_x86 *);
204 
205 #ifdef CONFIG_X86_32
206 extern int have_cpuid_p(void);
207 #else
208 static inline int have_cpuid_p(void)
209 {
210 	return 1;
211 }
212 #endif
213 static inline void native_cpuid(unsigned int *eax, unsigned int *ebx,
214 				unsigned int *ecx, unsigned int *edx)
215 {
216 	/* ecx is often an input as well as an output. */
217 	asm volatile("cpuid"
218 	    : "=a" (*eax),
219 	      "=b" (*ebx),
220 	      "=c" (*ecx),
221 	      "=d" (*edx)
222 	    : "0" (*eax), "2" (*ecx)
223 	    : "memory");
224 }
225 
226 #define native_cpuid_reg(reg)					\
227 static inline unsigned int native_cpuid_##reg(unsigned int op)	\
228 {								\
229 	unsigned int eax = op, ebx, ecx = 0, edx;		\
230 								\
231 	native_cpuid(&eax, &ebx, &ecx, &edx);			\
232 								\
233 	return reg;						\
234 }
235 
236 /*
237  * Native CPUID functions returning a single datum.
238  */
239 native_cpuid_reg(eax)
240 native_cpuid_reg(ebx)
241 native_cpuid_reg(ecx)
242 native_cpuid_reg(edx)
243 
244 /*
245  * Friendlier CR3 helpers.
246  */
247 static inline unsigned long read_cr3_pa(void)
248 {
249 	return __read_cr3() & CR3_ADDR_MASK;
250 }
251 
252 static inline unsigned long native_read_cr3_pa(void)
253 {
254 	return __native_read_cr3() & CR3_ADDR_MASK;
255 }
256 
257 static inline void load_cr3(pgd_t *pgdir)
258 {
259 	write_cr3(__sme_pa(pgdir));
260 }
261 
262 /*
263  * Note that while the legacy 'TSS' name comes from 'Task State Segment',
264  * on modern x86 CPUs the TSS also holds information important to 64-bit mode,
265  * unrelated to the task-switch mechanism:
266  */
267 #ifdef CONFIG_X86_32
268 /* This is the TSS defined by the hardware. */
269 struct x86_hw_tss {
270 	unsigned short		back_link, __blh;
271 	unsigned long		sp0;
272 	unsigned short		ss0, __ss0h;
273 	unsigned long		sp1;
274 
275 	/*
276 	 * We don't use ring 1, so ss1 is a convenient scratch space in
277 	 * the same cacheline as sp0.  We use ss1 to cache the value in
278 	 * MSR_IA32_SYSENTER_CS.  When we context switch
279 	 * MSR_IA32_SYSENTER_CS, we first check if the new value being
280 	 * written matches ss1, and, if it's not, then we wrmsr the new
281 	 * value and update ss1.
282 	 *
283 	 * The only reason we context switch MSR_IA32_SYSENTER_CS is
284 	 * that we set it to zero in vm86 tasks to avoid corrupting the
285 	 * stack if we were to go through the sysenter path from vm86
286 	 * mode.
287 	 */
288 	unsigned short		ss1;	/* MSR_IA32_SYSENTER_CS */
289 
290 	unsigned short		__ss1h;
291 	unsigned long		sp2;
292 	unsigned short		ss2, __ss2h;
293 	unsigned long		__cr3;
294 	unsigned long		ip;
295 	unsigned long		flags;
296 	unsigned long		ax;
297 	unsigned long		cx;
298 	unsigned long		dx;
299 	unsigned long		bx;
300 	unsigned long		sp;
301 	unsigned long		bp;
302 	unsigned long		si;
303 	unsigned long		di;
304 	unsigned short		es, __esh;
305 	unsigned short		cs, __csh;
306 	unsigned short		ss, __ssh;
307 	unsigned short		ds, __dsh;
308 	unsigned short		fs, __fsh;
309 	unsigned short		gs, __gsh;
310 	unsigned short		ldt, __ldth;
311 	unsigned short		trace;
312 	unsigned short		io_bitmap_base;
313 
314 } __attribute__((packed));
315 #else
316 struct x86_hw_tss {
317 	u32			reserved1;
318 	u64			sp0;
319 	u64			sp1;
320 
321 	/*
322 	 * Since Linux does not use ring 2, the 'sp2' slot is unused by
323 	 * hardware.  entry_SYSCALL_64 uses it as scratch space to stash
324 	 * the user RSP value.
325 	 */
326 	u64			sp2;
327 
328 	u64			reserved2;
329 	u64			ist[7];
330 	u32			reserved3;
331 	u32			reserved4;
332 	u16			reserved5;
333 	u16			io_bitmap_base;
334 
335 } __attribute__((packed));
336 #endif
337 
338 /*
339  * IO-bitmap sizes:
340  */
341 #define IO_BITMAP_BITS			65536
342 #define IO_BITMAP_BYTES			(IO_BITMAP_BITS / BITS_PER_BYTE)
343 #define IO_BITMAP_LONGS			(IO_BITMAP_BYTES / sizeof(long))
344 
345 #define IO_BITMAP_OFFSET_VALID_MAP				\
346 	(offsetof(struct tss_struct, io_bitmap.bitmap) -	\
347 	 offsetof(struct tss_struct, x86_tss))
348 
349 #define IO_BITMAP_OFFSET_VALID_ALL				\
350 	(offsetof(struct tss_struct, io_bitmap.mapall) -	\
351 	 offsetof(struct tss_struct, x86_tss))
352 
353 #ifdef CONFIG_X86_IOPL_IOPERM
354 /*
355  * sizeof(unsigned long) coming from an extra "long" at the end of the
356  * iobitmap. The limit is inclusive, i.e. the last valid byte.
357  */
358 # define __KERNEL_TSS_LIMIT	\
359 	(IO_BITMAP_OFFSET_VALID_ALL + IO_BITMAP_BYTES + \
360 	 sizeof(unsigned long) - 1)
361 #else
362 # define __KERNEL_TSS_LIMIT	\
363 	(offsetof(struct tss_struct, x86_tss) + sizeof(struct x86_hw_tss) - 1)
364 #endif
365 
366 /* Base offset outside of TSS_LIMIT so unpriviledged IO causes #GP */
367 #define IO_BITMAP_OFFSET_INVALID	(__KERNEL_TSS_LIMIT + 1)
368 
369 struct entry_stack {
370 	char	stack[PAGE_SIZE];
371 };
372 
373 struct entry_stack_page {
374 	struct entry_stack stack;
375 } __aligned(PAGE_SIZE);
376 
377 /*
378  * All IO bitmap related data stored in the TSS:
379  */
380 struct x86_io_bitmap {
381 	/* The sequence number of the last active bitmap. */
382 	u64			prev_sequence;
383 
384 	/*
385 	 * Store the dirty size of the last io bitmap offender. The next
386 	 * one will have to do the cleanup as the switch out to a non io
387 	 * bitmap user will just set x86_tss.io_bitmap_base to a value
388 	 * outside of the TSS limit. So for sane tasks there is no need to
389 	 * actually touch the io_bitmap at all.
390 	 */
391 	unsigned int		prev_max;
392 
393 	/*
394 	 * The extra 1 is there because the CPU will access an
395 	 * additional byte beyond the end of the IO permission
396 	 * bitmap. The extra byte must be all 1 bits, and must
397 	 * be within the limit.
398 	 */
399 	unsigned long		bitmap[IO_BITMAP_LONGS + 1];
400 
401 	/*
402 	 * Special I/O bitmap to emulate IOPL(3). All bytes zero,
403 	 * except the additional byte at the end.
404 	 */
405 	unsigned long		mapall[IO_BITMAP_LONGS + 1];
406 };
407 
408 struct tss_struct {
409 	/*
410 	 * The fixed hardware portion.  This must not cross a page boundary
411 	 * at risk of violating the SDM's advice and potentially triggering
412 	 * errata.
413 	 */
414 	struct x86_hw_tss	x86_tss;
415 
416 	struct x86_io_bitmap	io_bitmap;
417 } __aligned(PAGE_SIZE);
418 
419 DECLARE_PER_CPU_PAGE_ALIGNED(struct tss_struct, cpu_tss_rw);
420 
421 /* Per CPU interrupt stacks */
422 struct irq_stack {
423 	char		stack[IRQ_STACK_SIZE];
424 } __aligned(IRQ_STACK_SIZE);
425 
426 DECLARE_PER_CPU(unsigned long, cpu_current_top_of_stack);
427 
428 #ifdef CONFIG_X86_64
429 struct fixed_percpu_data {
430 	/*
431 	 * GCC hardcodes the stack canary as %gs:40.  Since the
432 	 * irq_stack is the object at %gs:0, we reserve the bottom
433 	 * 48 bytes of the irq stack for the canary.
434 	 *
435 	 * Once we are willing to require -mstack-protector-guard-symbol=
436 	 * support for x86_64 stackprotector, we can get rid of this.
437 	 */
438 	char		gs_base[40];
439 	unsigned long	stack_canary;
440 };
441 
442 DECLARE_PER_CPU_FIRST(struct fixed_percpu_data, fixed_percpu_data) __visible;
443 DECLARE_INIT_PER_CPU(fixed_percpu_data);
444 
445 static inline unsigned long cpu_kernelmode_gs_base(int cpu)
446 {
447 	return (unsigned long)per_cpu(fixed_percpu_data.gs_base, cpu);
448 }
449 
450 DECLARE_PER_CPU(void *, hardirq_stack_ptr);
451 DECLARE_PER_CPU(bool, hardirq_stack_inuse);
452 extern asmlinkage void ignore_sysret(void);
453 
454 /* Save actual FS/GS selectors and bases to current->thread */
455 void current_save_fsgs(void);
456 #else	/* X86_64 */
457 #ifdef CONFIG_STACKPROTECTOR
458 DECLARE_PER_CPU(unsigned long, __stack_chk_guard);
459 #endif
460 DECLARE_PER_CPU(struct irq_stack *, hardirq_stack_ptr);
461 DECLARE_PER_CPU(struct irq_stack *, softirq_stack_ptr);
462 #endif	/* !X86_64 */
463 
464 extern unsigned int fpu_kernel_xstate_size;
465 extern unsigned int fpu_user_xstate_size;
466 
467 struct perf_event;
468 
469 struct thread_struct {
470 	/* Cached TLS descriptors: */
471 	struct desc_struct	tls_array[GDT_ENTRY_TLS_ENTRIES];
472 #ifdef CONFIG_X86_32
473 	unsigned long		sp0;
474 #endif
475 	unsigned long		sp;
476 #ifdef CONFIG_X86_32
477 	unsigned long		sysenter_cs;
478 #else
479 	unsigned short		es;
480 	unsigned short		ds;
481 	unsigned short		fsindex;
482 	unsigned short		gsindex;
483 #endif
484 
485 #ifdef CONFIG_X86_64
486 	unsigned long		fsbase;
487 	unsigned long		gsbase;
488 #else
489 	/*
490 	 * XXX: this could presumably be unsigned short.  Alternatively,
491 	 * 32-bit kernels could be taught to use fsindex instead.
492 	 */
493 	unsigned long fs;
494 	unsigned long gs;
495 #endif
496 
497 	/* Save middle states of ptrace breakpoints */
498 	struct perf_event	*ptrace_bps[HBP_NUM];
499 	/* Debug status used for traps, single steps, etc... */
500 	unsigned long           virtual_dr6;
501 	/* Keep track of the exact dr7 value set by the user */
502 	unsigned long           ptrace_dr7;
503 	/* Fault info: */
504 	unsigned long		cr2;
505 	unsigned long		trap_nr;
506 	unsigned long		error_code;
507 #ifdef CONFIG_VM86
508 	/* Virtual 86 mode info */
509 	struct vm86		*vm86;
510 #endif
511 	/* IO permissions: */
512 	struct io_bitmap	*io_bitmap;
513 
514 	/*
515 	 * IOPL. Privilege level dependent I/O permission which is
516 	 * emulated via the I/O bitmap to prevent user space from disabling
517 	 * interrupts.
518 	 */
519 	unsigned long		iopl_emul;
520 
521 	unsigned int		sig_on_uaccess_err:1;
522 
523 	/*
524 	 * Protection Keys Register for Userspace.  Loaded immediately on
525 	 * context switch. Store it in thread_struct to avoid a lookup in
526 	 * the tasks's FPU xstate buffer. This value is only valid when a
527 	 * task is scheduled out. For 'current' the authoritative source of
528 	 * PKRU is the hardware itself.
529 	 */
530 	u32			pkru;
531 
532 	/* Floating point and extended processor state */
533 	struct fpu		fpu;
534 	/*
535 	 * WARNING: 'fpu' is dynamically-sized.  It *MUST* be at
536 	 * the end.
537 	 */
538 };
539 
540 /* Whitelist the FPU state from the task_struct for hardened usercopy. */
541 static inline void arch_thread_struct_whitelist(unsigned long *offset,
542 						unsigned long *size)
543 {
544 	*offset = offsetof(struct thread_struct, fpu.state);
545 	*size = fpu_kernel_xstate_size;
546 }
547 
548 static inline void
549 native_load_sp0(unsigned long sp0)
550 {
551 	this_cpu_write(cpu_tss_rw.x86_tss.sp0, sp0);
552 }
553 
554 static __always_inline void native_swapgs(void)
555 {
556 #ifdef CONFIG_X86_64
557 	asm volatile("swapgs" ::: "memory");
558 #endif
559 }
560 
561 static inline unsigned long current_top_of_stack(void)
562 {
563 	/*
564 	 *  We can't read directly from tss.sp0: sp0 on x86_32 is special in
565 	 *  and around vm86 mode and sp0 on x86_64 is special because of the
566 	 *  entry trampoline.
567 	 */
568 	return this_cpu_read_stable(cpu_current_top_of_stack);
569 }
570 
571 static inline bool on_thread_stack(void)
572 {
573 	return (unsigned long)(current_top_of_stack() -
574 			       current_stack_pointer) < THREAD_SIZE;
575 }
576 
577 #ifdef CONFIG_PARAVIRT_XXL
578 #include <asm/paravirt.h>
579 #else
580 #define __cpuid			native_cpuid
581 
582 static inline void load_sp0(unsigned long sp0)
583 {
584 	native_load_sp0(sp0);
585 }
586 
587 #endif /* CONFIG_PARAVIRT_XXL */
588 
589 /* Free all resources held by a thread. */
590 extern void release_thread(struct task_struct *);
591 
592 unsigned long get_wchan(struct task_struct *p);
593 
594 /*
595  * Generic CPUID function
596  * clear %ecx since some cpus (Cyrix MII) do not set or clear %ecx
597  * resulting in stale register contents being returned.
598  */
599 static inline void cpuid(unsigned int op,
600 			 unsigned int *eax, unsigned int *ebx,
601 			 unsigned int *ecx, unsigned int *edx)
602 {
603 	*eax = op;
604 	*ecx = 0;
605 	__cpuid(eax, ebx, ecx, edx);
606 }
607 
608 /* Some CPUID calls want 'count' to be placed in ecx */
609 static inline void cpuid_count(unsigned int op, int count,
610 			       unsigned int *eax, unsigned int *ebx,
611 			       unsigned int *ecx, unsigned int *edx)
612 {
613 	*eax = op;
614 	*ecx = count;
615 	__cpuid(eax, ebx, ecx, edx);
616 }
617 
618 /*
619  * CPUID functions returning a single datum
620  */
621 static inline unsigned int cpuid_eax(unsigned int op)
622 {
623 	unsigned int eax, ebx, ecx, edx;
624 
625 	cpuid(op, &eax, &ebx, &ecx, &edx);
626 
627 	return eax;
628 }
629 
630 static inline unsigned int cpuid_ebx(unsigned int op)
631 {
632 	unsigned int eax, ebx, ecx, edx;
633 
634 	cpuid(op, &eax, &ebx, &ecx, &edx);
635 
636 	return ebx;
637 }
638 
639 static inline unsigned int cpuid_ecx(unsigned int op)
640 {
641 	unsigned int eax, ebx, ecx, edx;
642 
643 	cpuid(op, &eax, &ebx, &ecx, &edx);
644 
645 	return ecx;
646 }
647 
648 static inline unsigned int cpuid_edx(unsigned int op)
649 {
650 	unsigned int eax, ebx, ecx, edx;
651 
652 	cpuid(op, &eax, &ebx, &ecx, &edx);
653 
654 	return edx;
655 }
656 
657 extern void select_idle_routine(const struct cpuinfo_x86 *c);
658 extern void amd_e400_c1e_apic_setup(void);
659 
660 extern unsigned long		boot_option_idle_override;
661 
662 enum idle_boot_override {IDLE_NO_OVERRIDE=0, IDLE_HALT, IDLE_NOMWAIT,
663 			 IDLE_POLL};
664 
665 extern void enable_sep_cpu(void);
666 extern int sysenter_setup(void);
667 
668 
669 /* Defined in head.S */
670 extern struct desc_ptr		early_gdt_descr;
671 
672 extern void switch_to_new_gdt(int);
673 extern void load_direct_gdt(int);
674 extern void load_fixmap_gdt(int);
675 extern void load_percpu_segment(int);
676 extern void cpu_init(void);
677 extern void cpu_init_secondary(void);
678 extern void cpu_init_exception_handling(void);
679 extern void cr4_init(void);
680 
681 static inline unsigned long get_debugctlmsr(void)
682 {
683 	unsigned long debugctlmsr = 0;
684 
685 #ifndef CONFIG_X86_DEBUGCTLMSR
686 	if (boot_cpu_data.x86 < 6)
687 		return 0;
688 #endif
689 	rdmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
690 
691 	return debugctlmsr;
692 }
693 
694 static inline void update_debugctlmsr(unsigned long debugctlmsr)
695 {
696 #ifndef CONFIG_X86_DEBUGCTLMSR
697 	if (boot_cpu_data.x86 < 6)
698 		return;
699 #endif
700 	wrmsrl(MSR_IA32_DEBUGCTLMSR, debugctlmsr);
701 }
702 
703 extern void set_task_blockstep(struct task_struct *task, bool on);
704 
705 /* Boot loader type from the setup header: */
706 extern int			bootloader_type;
707 extern int			bootloader_version;
708 
709 extern char			ignore_fpu_irq;
710 
711 #define HAVE_ARCH_PICK_MMAP_LAYOUT 1
712 #define ARCH_HAS_PREFETCHW
713 #define ARCH_HAS_SPINLOCK_PREFETCH
714 
715 #ifdef CONFIG_X86_32
716 # define BASE_PREFETCH		""
717 # define ARCH_HAS_PREFETCH
718 #else
719 # define BASE_PREFETCH		"prefetcht0 %P1"
720 #endif
721 
722 /*
723  * Prefetch instructions for Pentium III (+) and AMD Athlon (+)
724  *
725  * It's not worth to care about 3dnow prefetches for the K6
726  * because they are microcoded there and very slow.
727  */
728 static inline void prefetch(const void *x)
729 {
730 	alternative_input(BASE_PREFETCH, "prefetchnta %P1",
731 			  X86_FEATURE_XMM,
732 			  "m" (*(const char *)x));
733 }
734 
735 /*
736  * 3dnow prefetch to get an exclusive cache line.
737  * Useful for spinlocks to avoid one state transition in the
738  * cache coherency protocol:
739  */
740 static __always_inline void prefetchw(const void *x)
741 {
742 	alternative_input(BASE_PREFETCH, "prefetchw %P1",
743 			  X86_FEATURE_3DNOWPREFETCH,
744 			  "m" (*(const char *)x));
745 }
746 
747 static inline void spin_lock_prefetch(const void *x)
748 {
749 	prefetchw(x);
750 }
751 
752 #define TOP_OF_INIT_STACK ((unsigned long)&init_stack + sizeof(init_stack) - \
753 			   TOP_OF_KERNEL_STACK_PADDING)
754 
755 #define task_top_of_stack(task) ((unsigned long)(task_pt_regs(task) + 1))
756 
757 #define task_pt_regs(task) \
758 ({									\
759 	unsigned long __ptr = (unsigned long)task_stack_page(task);	\
760 	__ptr += THREAD_SIZE - TOP_OF_KERNEL_STACK_PADDING;		\
761 	((struct pt_regs *)__ptr) - 1;					\
762 })
763 
764 #ifdef CONFIG_X86_32
765 #define INIT_THREAD  {							  \
766 	.sp0			= TOP_OF_INIT_STACK,			  \
767 	.sysenter_cs		= __KERNEL_CS,				  \
768 }
769 
770 #define KSTK_ESP(task)		(task_pt_regs(task)->sp)
771 
772 #else
773 #define INIT_THREAD { }
774 
775 extern unsigned long KSTK_ESP(struct task_struct *task);
776 
777 #endif /* CONFIG_X86_64 */
778 
779 extern void start_thread(struct pt_regs *regs, unsigned long new_ip,
780 					       unsigned long new_sp);
781 
782 /*
783  * This decides where the kernel will search for a free chunk of vm
784  * space during mmap's.
785  */
786 #define __TASK_UNMAPPED_BASE(task_size)	(PAGE_ALIGN(task_size / 3))
787 #define TASK_UNMAPPED_BASE		__TASK_UNMAPPED_BASE(TASK_SIZE_LOW)
788 
789 #define KSTK_EIP(task)		(task_pt_regs(task)->ip)
790 
791 /* Get/set a process' ability to use the timestamp counter instruction */
792 #define GET_TSC_CTL(adr)	get_tsc_mode((adr))
793 #define SET_TSC_CTL(val)	set_tsc_mode((val))
794 
795 extern int get_tsc_mode(unsigned long adr);
796 extern int set_tsc_mode(unsigned int val);
797 
798 DECLARE_PER_CPU(u64, msr_misc_features_shadow);
799 
800 extern u16 get_llc_id(unsigned int cpu);
801 
802 #ifdef CONFIG_CPU_SUP_AMD
803 extern u32 amd_get_nodes_per_socket(void);
804 extern u32 amd_get_highest_perf(void);
805 #else
806 static inline u32 amd_get_nodes_per_socket(void)	{ return 0; }
807 static inline u32 amd_get_highest_perf(void)		{ return 0; }
808 #endif
809 
810 static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves)
811 {
812 	uint32_t base, eax, signature[3];
813 
814 	for (base = 0x40000000; base < 0x40010000; base += 0x100) {
815 		cpuid(base, &eax, &signature[0], &signature[1], &signature[2]);
816 
817 		if (!memcmp(sig, signature, 12) &&
818 		    (leaves == 0 || ((eax - base) >= leaves)))
819 			return base;
820 	}
821 
822 	return 0;
823 }
824 
825 extern unsigned long arch_align_stack(unsigned long sp);
826 void free_init_pages(const char *what, unsigned long begin, unsigned long end);
827 extern void free_kernel_image_pages(const char *what, void *begin, void *end);
828 
829 void default_idle(void);
830 #ifdef	CONFIG_XEN
831 bool xen_set_default_idle(void);
832 #else
833 #define xen_set_default_idle 0
834 #endif
835 
836 void stop_this_cpu(void *dummy);
837 void microcode_check(void);
838 
839 enum l1tf_mitigations {
840 	L1TF_MITIGATION_OFF,
841 	L1TF_MITIGATION_FLUSH_NOWARN,
842 	L1TF_MITIGATION_FLUSH,
843 	L1TF_MITIGATION_FLUSH_NOSMT,
844 	L1TF_MITIGATION_FULL,
845 	L1TF_MITIGATION_FULL_FORCE
846 };
847 
848 extern enum l1tf_mitigations l1tf_mitigation;
849 
850 enum mds_mitigations {
851 	MDS_MITIGATION_OFF,
852 	MDS_MITIGATION_FULL,
853 	MDS_MITIGATION_VMWERV,
854 };
855 
856 #endif /* _ASM_X86_PROCESSOR_H */
857