xref: /illumos-gate/usr/src/uts/intel/sys/fp.h (revision 7e3dbbac48aaad67ac841ba479a67a2081d6a02b)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
23  * Copyright (c) 2018, Joyent, Inc.
24  *
25  * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
26  */
27 
28 /*	Copyright (c) 1990, 1991 UNIX System Laboratories, Inc.	*/
29 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T	*/
30 /*		All Rights Reserved				*/
31 
32 #ifndef _SYS_FP_H
33 #define	_SYS_FP_H
34 
35 #ifdef __cplusplus
36 extern "C" {
37 #endif
38 
39 /*
40  * 80287/80387 and SSE/SSE2 floating point processor definitions
41  */
42 
43 /*
44  * values that go into fp_kind
45  */
46 #define	FP_NO	0	/* no fp chip, no emulator (no fp support)	*/
47 #define	FP_SW	1	/* no fp chip, using software emulator		*/
48 #define	FP_HW	2	/* chip present bit				*/
49 #define	FP_287	2	/* 80287 chip present				*/
50 #define	FP_387	3	/* 80387 chip present				*/
51 #define	FP_487	6	/* 80487 chip present				*/
52 #define	FP_486	6	/* 80486 chip present				*/
53 /*
54  * The following values are bit flags instead of actual values.
55  * E.g. to know if we are using SSE, test (value & __FP_SSE) instead
56  * of (value == __FP_SSE).
57  */
58 #define	__FP_SSE	0x100	/* .. plus SSE-capable CPU		*/
59 #define	__FP_AVX	0x200	/* .. plus AVX-capable CPU		*/
60 
61 /*
62  * values that go into fp_save_mech
63  */
64 #define	FP_FNSAVE	1	/* fnsave/frstor instructions		*/
65 #define	FP_FXSAVE	2	/* fxsave/fxrstor instructions		*/
66 #define	FP_XSAVE	3	/* xsave/xrstor instructions		*/
67 
68 /*
69  * masks for 80387 control word
70  */
71 #define	FPIM	0x00000001	/* invalid operation			*/
72 #define	FPDM	0x00000002	/* denormalized operand			*/
73 #define	FPZM	0x00000004	/* zero divide				*/
74 #define	FPOM	0x00000008	/* overflow				*/
75 #define	FPUM	0x00000010	/* underflow				*/
76 #define	FPPM	0x00000020	/* precision				*/
77 #define	FPPC	0x00000300	/* precision control			*/
78 #define	FPRC	0x00000C00	/* rounding control			*/
79 #define	FPIC	0x00001000	/* infinity control			*/
80 #define	WFPDE	0x00000080	/* data chain exception			*/
81 
82 /*
83  * (Old symbol compatibility)
84  */
85 #define	FPINV	FPIM
86 #define	FPDNO	FPDM
87 #define	FPZDIV	FPZM
88 #define	FPOVR	FPOM
89 #define	FPUNR	FPUM
90 #define	FPPRE	FPPM
91 
92 /*
93  * precision, rounding, and infinity options in control word
94  */
95 #define	FPSIG24 0x00000000	/* 24-bit significand precision (short) */
96 #define	FPSIG53 0x00000200	/* 53-bit significand precision (long)	*/
97 #define	FPSIG64 0x00000300	/* 64-bit significand precision (temp)	*/
98 #define	FPRTN	0x00000000	/* round to nearest or even		*/
99 #define	FPRD	0x00000400	/* round down				*/
100 #define	FPRU	0x00000800	/* round up				*/
101 #define	FPCHOP	0x00000C00	/* chop (truncate toward zero)		*/
102 #define	FPP	0x00000000	/* projective infinity			*/
103 #define	FPA	0x00001000	/* affine infinity			*/
104 #define	WFPB17	0x00020000	/* bit 17				*/
105 #define	WFPB24	0x00040000	/* bit 24				*/
106 
107 /*
108  * masks for 80387 status word
109  */
110 #define	FPS_IE	0x00000001	/* invalid operation			*/
111 #define	FPS_DE	0x00000002	/* denormalized operand			*/
112 #define	FPS_ZE	0x00000004	/* zero divide				*/
113 #define	FPS_OE	0x00000008	/* overflow				*/
114 #define	FPS_UE	0x00000010	/* underflow				*/
115 #define	FPS_PE	0x00000020	/* precision				*/
116 #define	FPS_SF	0x00000040	/* stack fault				*/
117 #define	FPS_ES	0x00000080	/* error summary bit			*/
118 #define	FPS_C0	0x00000100	/* C0 bit				*/
119 #define	FPS_C1	0x00000200	/* C1 bit				*/
120 #define	FPS_C2	0x00000400	/* C2 bit				*/
121 #define	FPS_TOP	0x00003800	/* top of stack pointer			*/
122 #define	FPS_C3	0x00004000	/* C3 bit				*/
123 #define	FPS_B	0x00008000	/* busy bit				*/
124 
125 /*
126  * Exception flags manually cleared during x87 exception handling.
127  */
128 #define	FPS_SW_EFLAGS	\
129 	(FPS_IE|FPS_DE|FPS_ZE|FPS_OE|FPS_UE|FPS_PE|FPS_SF|FPS_ES|FPS_B)
130 
131 /*
132  * Initial value of FPU control word as per 4th ed. ABI document
133  * - affine infinity
134  * - round to nearest or even
135  * - 64-bit double precision
136  * - all exceptions masked
137  */
138 #define	FPU_CW_INIT	0x133f
139 
140 /*
141  * masks and flags for SSE/SSE2 MXCSR
142  */
143 #define	SSE_IE	0x00000001	/* invalid operation			*/
144 #define	SSE_DE	0x00000002	/* denormalized operand			*/
145 #define	SSE_ZE	0x00000004	/* zero divide				*/
146 #define	SSE_OE	0x00000008	/* overflow				*/
147 #define	SSE_UE	0x00000010	/* underflow				*/
148 #define	SSE_PE	0x00000020	/* precision				*/
149 #define	SSE_DAZ	0x00000040	/* denormals are zero			*/
150 #define	SSE_IM	0x00000080	/* invalid op exception mask		*/
151 #define	SSE_DM	0x00000100	/* denormalize exception mask		*/
152 #define	SSE_ZM	0x00000200	/* zero-divide exception mask		*/
153 #define	SSE_OM	0x00000400	/* overflow exception mask		*/
154 #define	SSE_UM	0x00000800	/* underflow exception mask		*/
155 #define	SSE_PM	0x00001000	/* precision exception mask		*/
156 #define	SSE_RC	0x00006000	/* rounding control			*/
157 #define	SSE_RD	0x00002000	/* rounding control: round down		*/
158 #define	SSE_RU	0x00004000	/* rounding control: round up		*/
159 #define	SSE_FZ	0x00008000	/* flush to zero for masked underflow	*/
160 
161 #define	SSE_MXCSR_EFLAGS	\
162 	(SSE_IE|SSE_DE|SSE_ZE|SSE_OE|SSE_UE|SSE_PE)	/* 0x3f */
163 
164 #define	SSE_MXCSR_INIT	\
165 	(SSE_IM|SSE_DM|SSE_ZM|SSE_OM|SSE_UM|SSE_PM)	/* 0x1f80 */
166 
167 #define	SSE_MXCSR_MASK_DEFAULT	\
168 	(0xffff & ~SSE_DAZ)				/* 0xffbf */
169 
170 #define	SSE_FMT_MXCSR	\
171 	"\20\20fz\17ru\16rd\15pm\14um\13om\12zm\11dm"	\
172 	"\10im\7daz\6pe\5ue\4oe\3ze\2de\1ie"
173 
174 /*
175  * This structure is written to memory by an 'fnsave' instruction
176  */
177 struct fnsave_state {
178 	uint16_t	f_fcw;
179 	uint16_t	__f_ign0;
180 	uint16_t	f_fsw;
181 	uint16_t	__f_ign1;
182 	uint16_t	f_ftw;
183 	uint16_t	__f_ign2;
184 	uint32_t	f_eip;
185 	uint16_t	f_cs;
186 	uint16_t	f_fop;
187 	uint32_t	f_dp;
188 	uint16_t	f_ds;
189 	uint16_t	__f_ign3;
190 	union {
191 		uint16_t fpr_16[5];	/* 80-bits of x87 state */
192 	} f_st[8];
193 };	/* 108 bytes */
194 
195 /*
196  * This structure is written to memory by an 'fxsave' instruction
197  * Note the variant behaviour of this instruction between long mode
198  * and legacy environments!
199  */
200 struct fxsave_state {
201 	uint16_t	fx_fcw;
202 	uint16_t	fx_fsw;
203 	uint16_t	fx_fctw;	/* compressed tag word */
204 	uint16_t	fx_fop;
205 #if defined(__amd64)
206 	uint64_t	fx_rip;
207 	uint64_t	fx_rdp;
208 #else
209 	uint32_t	fx_eip;
210 	uint16_t	fx_cs;
211 	uint16_t	__fx_ign0;
212 	uint32_t	fx_dp;
213 	uint16_t	fx_ds;
214 	uint16_t	__fx_ign1;
215 #endif
216 	uint32_t	fx_mxcsr;
217 	uint32_t	fx_mxcsr_mask;
218 	union {
219 		uint16_t fpr_16[5];	/* 80-bits of x87 state */
220 		u_longlong_t fpr_mmx;	/* 64-bit mmx register */
221 		uint32_t __fpr_pad[4];	/* (pad out to 128-bits) */
222 	} fx_st[8];
223 #if defined(__amd64)
224 	upad128_t	fx_xmm[16];	/* 128-bit registers */
225 	upad128_t	__fx_ign2[6];
226 #else
227 	upad128_t	fx_xmm[8];	/* 128-bit registers */
228 	upad128_t	__fx_ign2[14];
229 #endif
230 } __aligned(16);	/* 512 bytes */
231 
232 /*
233  * This structure is written to memory by one of the 'xsave' instruction
234  * variants. The first 512 bytes are compatible with the format of the 'fxsave'
235  * area. The header portion of the xsave layout is documented in section
236  * 13.4.2 of the Intel 64 and IA-32 Architectures Software Developer’s Manual,
237  * Volume 1 (IASDv1). The extended portion is documented in section 13.4.3.
238  *
239  * Our size is at least AVX_XSAVE_SIZE (832 bytes), which is asserted
240  * statically.  Enabling additional xsave-related CPU features requires an
241  * increase in the size. We dynamically allocate the per-lwp xsave area at
242  * runtime, based on the size needed for the CPU-specific features. This
243  * xsave_state structure simply defines our historical layout for the beginning
244  * of the xsave area. The locations and size of new, extended, components is
245  * determined dynamically by querying the CPU. See the xsave_info structure in
246  * cpuid.c.
247  *
248  * xsave component usage is tracked using bits in the xs_xstate_bv field. The
249  * components are documented in section 13.1 of IASDv1. For easy reference,
250  * this is a summary of the currently defined component bit definitions:
251  *	x87			0x0001
252  *	SSE			0x0002
253  *	AVX			0x0004
254  *	bndreg (MPX)		0x0008
255  *	bndcsr (MPX)		0x0010
256  *	opmask (AVX512)		0x0020
257  *	zmm hi256 (AVX512)	0x0040
258  *	zmm hi16 (AVX512)	0x0080
259  *	PT			0x0100
260  *	PKRU			0x0200
261  * When xsaveopt_ctxt is being used to save into the xsave_state area, the
262  * xs_xstate_bv field is updated by the xsaveopt instruction to indicate which
263  * elements of the xsave area are active.
264  *
265  * xs_xcomp_bv should always be 0, since we do not currently use the compressed
266  * form of xsave (xsavec).
267  */
268 struct xsave_state {
269 	struct fxsave_state	xs_fxsave;	/* 0-511 legacy region */
270 	uint64_t		xs_xstate_bv;	/* 512-519 start xsave header */
271 	uint64_t		xs_xcomp_bv;	/* 520-527 */
272 	uint64_t		xs_reserved[6];	/* 528-575 end xsave header */
273 	upad128_t		xs_ymm[16];	/* 576 AVX component */
274 } __aligned(64);
275 
276 /*
277  * Kernel's FPU save area
278  */
279 typedef struct {
280 	union _kfpu_u {
281 		void *kfpu_generic;
282 		struct fxsave_state *kfpu_fx;
283 #if defined(__i386)
284 		struct fnsave_state *kfpu_fn;
285 #endif
286 		struct xsave_state *kfpu_xs;
287 	} kfpu_u;
288 	uint32_t kfpu_status;		/* saved at #mf exception */
289 	uint32_t kfpu_xstatus;		/* saved at #xm exception */
290 } kfpu_t;
291 
292 extern int fp_kind;		/* kind of fp support			*/
293 extern int fp_save_mech;	/* fp save/restore mechanism		*/
294 extern int fpu_exists;		/* FPU hw exists			*/
295 
296 #ifdef _KERNEL
297 
298 extern int fpu_ignored;
299 extern int fpu_pentium_fdivbug;
300 
301 extern uint32_t sse_mxcsr_mask;
302 
303 extern void fpu_probe(void);
304 extern uint_t fpu_initial_probe(void);
305 
306 extern void fpu_auxv_info(int *, size_t *);
307 
308 extern void fpnsave_ctxt(void *);
309 extern void fpxsave_ctxt(void *);
310 extern void xsave_ctxt(void *);
311 extern void xsaveopt_ctxt(void *);
312 extern void fpxsave_excp_clr_ctxt(void *);
313 extern void xsave_excp_clr_ctxt(void *);
314 extern void xsaveopt_excp_clr_ctxt(void *);
315 extern void (*fpsave_ctxt)(void *);
316 extern void (*xsavep)(struct xsave_state *, uint64_t);
317 
318 extern void fpxrestore_ctxt(void *);
319 extern void xrestore_ctxt(void *);
320 extern void (*fprestore_ctxt)(void *);
321 
322 extern void fxsave_insn(struct fxsave_state *);
323 extern void fpsave(struct fnsave_state *);
324 extern void fprestore(struct fnsave_state *);
325 extern void fpxsave(struct fxsave_state *);
326 extern void fpxrestore(struct fxsave_state *);
327 extern void xsave(struct xsave_state *, uint64_t);
328 extern void xsaveopt(struct xsave_state *, uint64_t);
329 extern void xrestore(struct xsave_state *, uint64_t);
330 
331 extern void fpenable(void);
332 extern void fpdisable(void);
333 extern void fpinit(void);
334 
335 extern uint32_t fperr_reset(void);
336 extern uint32_t fpxerr_reset(void);
337 
338 extern uint32_t fpgetcwsw(void);
339 extern uint32_t fpgetmxcsr(void);
340 
341 struct regs;
342 extern int fpexterrflt(struct regs *);
343 extern int fpsimderrflt(struct regs *);
344 extern void fpsetcw(uint16_t, uint32_t);
345 extern void fp_seed(void);
346 extern void fp_exec(void);
347 struct _klwp;
348 extern void fp_lwp_init(struct _klwp *);
349 extern void fp_lwp_cleanup(struct _klwp *);
350 extern void fp_lwp_dup(struct _klwp *);
351 
352 extern const struct fxsave_state sse_initial;
353 extern const struct xsave_state avx_initial;
354 
355 #endif	/* _KERNEL */
356 
357 #ifdef __cplusplus
358 }
359 #endif
360 
361 #endif	/* _SYS_FP_H */
362