xref: /netbsd-src/sys/arch/m68k/fpsp/fpsp.h (revision 57fb77a14ebcd83f1fae16b59e7b83fd0f166e03)
1 *	$NetBSD: fpsp.h,v 1.2 1994/10/26 07:49:04 cgd Exp $
2 
3 *	MOTOROLA MICROPROCESSOR & MEMORY TECHNOLOGY GROUP
4 *	M68000 Hi-Performance Microprocessor Division
5 *	M68040 Software Package
6 *
7 *	M68040 Software Package Copyright (c) 1993, 1994 Motorola Inc.
8 *	All rights reserved.
9 *
10 *	THE SOFTWARE is provided on an "AS IS" basis and without warranty.
11 *	To the maximum extent permitted by applicable law,
12 *	MOTOROLA DISCLAIMS ALL WARRANTIES WHETHER EXPRESS OR IMPLIED,
13 *	INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A
14 *	PARTICULAR PURPOSE and any warranty against infringement with
15 *	regard to the SOFTWARE (INCLUDING ANY MODIFIED VERSIONS THEREOF)
16 *	and any accompanying written materials.
17 *
18 *	To the maximum extent permitted by applicable law,
19 *	IN NO EVENT SHALL MOTOROLA BE LIABLE FOR ANY DAMAGES WHATSOEVER
20 *	(INCLUDING WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS
21 *	PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR
22 *	OTHER PECUNIARY LOSS) ARISING OF THE USE OR INABILITY TO USE THE
23 *	SOFTWARE.  Motorola assumes no responsibility for the maintenance
24 *	and support of the SOFTWARE.
25 *
26 *	You are hereby granted a copyright license to use, modify, and
27 *	distribute the SOFTWARE so long as this entire notice is retained
28 *	without alteration in any modified and/or redistributed versions,
29 *	and that such modified versions are clearly identified as such.
30 *	No licenses are granted by implication, estoppel or otherwise
31 *	under any patents or trademarks of Motorola, Inc.
32 
33 *
34 *	fpsp.h 3.3 3.3
35 *
36 
37 *	fpsp.h --- stack frame offsets during FPSP exception handling
38 *
39 *	These equates are used to access the exception frame, the fsave
40 *	frame and any local variables needed by the FPSP package.
41 *
42 *	All FPSP handlers begin by executing:
43 *
44 *		link	a6,#-LOCAL_SIZE
45 *		fsave	-(a7)
46 *		movem.l	d0-d1/a0-a1,USER_DA(a6)
47 *		fmovem.x fp0-fp3,USER_FP0(a6)
48 *		fmove.l	fpsr/fpcr/fpiar,USER_FPSR(a6)
49 *
50 *	After initialization, the stack looks like this:
51 *
52 *	A7 --->	+-------------------------------+
53 *		|				|
54 *		|	FPU fsave area		|
55 *		|				|
56 *		+-------------------------------+
57 *		|				|
58 *		|	FPSP Local Variables	|
59 *		|	     including		|
60 *		|	  saved registers	|
61 *		|				|
62 *		+-------------------------------+
63 *	A6 --->	|	Saved A6		|
64 *		+-------------------------------+
65 *		|				|
66 *		|	Exception Frame		|
67 *		|				|
68 *		|				|
69 *
70 *	Positive offsets from A6 refer to the exception frame.  Negative
71 *	offsets refer to the Local Variable area and the fsave area.
72 *	The fsave frame is also accessible 'from the top' via A7.
73 *
74 *	On exit, the handlers execute:
75 *
76 *		movem.l	USER_DA(a6),d0-d1/a0-a1
77 *		fmovem.x USER_FP0(a6),fp0-fp3
78 *		fmove.l	USER_FPSR(a6),fpsr/fpcr/fpiar
79 *		frestore (a7)+
80 *		unlk	a6
81 *
82 *	and then either 'bra fpsp_done' if the exception was completely
83 *	handled	by the package, or 'bra real_xxxx' which is an external
84 *	label to a routine that will process a real exception of the
85 *	type that was generated.  Some handlers may omit the 'frestore'
86 *	if the FPU state after the exception is idle.
87 *
88 *	Sometimes the exception handler will transform the fsave area
89 *	because it needs to report an exception back to the user.  This
90 *	can happen if the package is entered for an unimplemented float
91 *	instruction that generates (say) an underflow.  Alternatively,
92 *	a second fsave frame can be pushed onto the stack and the
93 *	handler	exit code will reload the new frame and discard the old.
94 *
95 *	The registers d0, d1, a0, a1 and fp0-fp3 are always saved and
96 *	restored from the 'local variable' area and can be used as
97 *	temporaries.  If a routine needs to change any
98 *	of these registers, it should modify the saved copy and let
99 *	the handler exit code restore the value.
100 *
101 *----------------------------------------------------------------------
102 *
103 *	Local Variables on the stack
104 *
105 LOCAL_SIZE	equ	192		;bytes needed for local variables
106 LV		equ	-LOCAL_SIZE	;convenient base value
107 *
108 USER_DA		equ	LV+0		;save space for D0-D1,A0-A1
109 USER_D0		equ	LV+0		;saved user D0
110 USER_D1		equ	LV+4		;saved user D1
111 USER_A0		equ	LV+8		;saved user A0
112 USER_A1		equ	LV+12		;saved user A1
113 USER_FP0	equ	LV+16		;saved user FP0
114 USER_FP1	equ	LV+28		;saved user FP1
115 USER_FP2	equ	LV+40		;saved user FP2
116 USER_FP3	equ	LV+52		;saved user FP3
117 USER_FPCR	equ	LV+64		;saved user FPCR
118 FPCR_ENABLE	equ	USER_FPCR+2	;	FPCR exception enable
119 FPCR_MODE	equ	USER_FPCR+3	;	FPCR rounding mode control
120 USER_FPSR	equ	LV+68		;saved user FPSR
121 FPSR_CC		equ	USER_FPSR+0	;	FPSR condition code
122 FPSR_QBYTE	equ	USER_FPSR+1	;	FPSR quotient
123 FPSR_EXCEPT	equ	USER_FPSR+2	;	FPSR exception
124 FPSR_AEXCEPT	equ	USER_FPSR+3	;	FPSR accrued exception
125 USER_FPIAR	equ	LV+72		;saved user FPIAR
126 FP_SCR1		equ	LV+76		;room for a temporary float value
127 FP_SCR2		equ	LV+92		;room for a temporary float value
128 L_SCR1		equ	LV+108		;room for a temporary long value
129 L_SCR2		equ	LV+112		;room for a temporary long value
130 STORE_FLG	equ	LV+116
131 BINDEC_FLG	equ	LV+117		;used in bindec
132 DNRM_FLG	equ	LV+118		;used in res_func
133 RES_FLG		equ	LV+119		;used in res_func
134 DY_MO_FLG	equ	LV+120		;dyadic/monadic flag
135 UFLG_TMP	equ	LV+121		;temporary for uflag errata
136 CU_ONLY		equ	LV+122		;cu-only flag
137 VER_TMP		equ	LV+123		;temp holding for version number
138 L_SCR3		equ	LV+124		;room for a temporary long value
139 FP_SCR3		equ	LV+128		;room for a temporary float value
140 FP_SCR4		equ	LV+144		;room for a temporary float value
141 FP_SCR5		equ	LV+160		;room for a temporary float value
142 FP_SCR6		equ	LV+176
143 *
144 *NEXT		equ	LV+192		;need to increase LOCAL_SIZE
145 *
146 *--------------------------------------------------------------------------
147 *
148 *	fsave offsets and bit definitions
149 *
150 *	Offsets are defined from the end of an fsave because the last 10
151 *	words of a busy frame are the same as the unimplemented frame.
152 *
153 CU_SAVEPC	equ	LV-92		;micro-pc for CU (1 byte)
154 FPR_DIRTY_BITS	equ	LV-91		;fpr dirty bits
155 *
156 WBTEMP		equ	LV-76		;write back temp (12 bytes)
157 WBTEMP_EX	equ	WBTEMP		;wbtemp sign and exponent (2 bytes)
158 WBTEMP_HI	equ	WBTEMP+4	;wbtemp mantissa [63:32] (4 bytes)
159 WBTEMP_LO	equ	WBTEMP+8	;wbtemp mantissa [31:00] (4 bytes)
160 *
161 WBTEMP_SGN	equ	WBTEMP+2	;used to store sign
162 *
163 FPSR_SHADOW	equ	LV-64		;fpsr shadow reg
164 *
165 FPIARCU		equ	LV-60		;Instr. addr. reg. for CU (4 bytes)
166 *
167 CMDREG2B	equ	LV-52		;cmd reg for machine 2
168 CMDREG3B	equ	LV-48		;cmd reg for E3 exceptions (2 bytes)
169 *
170 NMNEXC		equ	LV-44		;NMNEXC (unsup,snan bits only)
171 nmn_unsup_bit	equ	1
172 nmn_snan_bit	equ	0
173 *
174 NMCEXC		equ	LV-43		;NMNEXC & NMCEXC
175 nmn_operr_bit	equ	7
176 nmn_ovfl_bit	equ	6
177 nmn_unfl_bit	equ	5
178 nmc_unsup_bit	equ	4
179 nmc_snan_bit	equ	3
180 nmc_operr_bit	equ	2
181 nmc_ovfl_bit	equ	1
182 nmc_unfl_bit	equ	0
183 *
184 STAG		equ	LV-40		;source tag (1 byte)
185 WBTEMP_GRS	equ	LV-40		;alias wbtemp guard, round, sticky
186 guard_bit	equ	1		;guard bit is bit number 1
187 round_bit	equ	0		;round bit is bit number 0
188 stag_mask	equ	$E0		;upper 3 bits are source tag type
189 denorm_bit	equ	7		;bit determins if denorm or unnorm
190 etemp15_bit	equ	4		;etemp exponent bit #15
191 wbtemp66_bit	equ	2		;wbtemp mantissa bit #66
192 wbtemp1_bit	equ	1		;wbtemp mantissa bit #1
193 wbtemp0_bit	equ	0		;wbtemp mantissa bit #0
194 *
195 STICKY		equ	LV-39		;holds sticky bit
196 sticky_bit	equ	7
197 *
198 CMDREG1B	equ	LV-36		;cmd reg for E1 exceptions (2 bytes)
199 kfact_bit	equ	12		;distinguishes static/dynamic k-factor
200 *					;on packed move out's.  NOTE: this
201 *					;equate only works when CMDREG1B is in
202 *					;a register.
203 *
204 CMDWORD		equ	LV-35		;command word in cmd1b
205 direction_bit	equ	5		;bit 0 in opclass
206 size_bit2	equ	12		;bit 2 in size field
207 *
208 DTAG		equ	LV-32		;dest tag (1 byte)
209 dtag_mask	equ	$E0		;upper 3 bits are dest type tag
210 fptemp15_bit	equ	4		;fptemp exponent bit #15
211 *
212 WB_BYTE		equ	LV-31		;holds WBTE15 bit (1 byte)
213 wbtemp15_bit	equ	4		;wbtemp exponent bit #15
214 *
215 E_BYTE		equ	LV-28		;holds E1 and E3 bits (1 byte)
216 E1		equ	2		;which bit is E1 flag
217 E3		equ	1		;which bit is E3 flag
218 SFLAG		equ	0		;which bit is S flag
219 *
220 T_BYTE		equ	LV-27		;holds T and U bits (1 byte)
221 XFLAG		equ	7		;which bit is X flag
222 UFLAG		equ	5		;which bit is U flag
223 TFLAG		equ	4		;which bit is T flag
224 *
225 FPTEMP		equ	LV-24		;fptemp (12 bytes)
226 FPTEMP_EX	equ	FPTEMP		;fptemp sign and exponent (2 bytes)
227 FPTEMP_HI	equ	FPTEMP+4	;fptemp mantissa [63:32] (4 bytes)
228 FPTEMP_LO	equ	FPTEMP+8	;fptemp mantissa [31:00] (4 bytes)
229 *
230 FPTEMP_SGN	equ	FPTEMP+2	;used to store sign
231 *
232 ETEMP		equ	LV-12		;etemp (12 bytes)
233 ETEMP_EX	equ	ETEMP		;etemp sign and exponent (2 bytes)
234 ETEMP_HI	equ	ETEMP+4		;etemp mantissa [63:32] (4 bytes)
235 ETEMP_LO	equ	ETEMP+8		;etemp mantissa [31:00] (4 bytes)
236 *
237 ETEMP_SGN	equ	ETEMP+2		;used to store sign
238 *
239 EXC_SR		equ	4		;exception frame status register
240 EXC_PC		equ	6		;exception frame program counter
241 EXC_VEC		equ	10		;exception frame vector (format+vector#)
242 EXC_EA		equ	12		;exception frame effective address
243 *
244 *--------------------------------------------------------------------------
245 *
246 *	FPSR/FPCR bits
247 *
248 neg_bit		equ	3	negative result
249 z_bit		equ	2	zero result
250 inf_bit		equ	1	infinity result
251 nan_bit		equ	0	not-a-number result
252 *
253 q_sn_bit	equ	7	sign bit of quotient byte
254 *
255 bsun_bit	equ	7	branch on unordered
256 snan_bit	equ	6	signalling nan
257 operr_bit	equ	5	operand error
258 ovfl_bit	equ	4	overflow
259 unfl_bit	equ	3	underflow
260 dz_bit		equ	2	divide by zero
261 inex2_bit	equ	1	inexact result 2
262 inex1_bit	equ	0	inexact result 1
263 *
264 aiop_bit	equ	7	accrued illegal operation
265 aovfl_bit	equ	6	accrued overflow
266 aunfl_bit	equ	5	accrued underflow
267 adz_bit		equ	4	accrued divide by zero
268 ainex_bit	equ	3	accrued inexact
269 *
270 *	FPSR individual bit masks
271 *
272 neg_mask	equ	$08000000
273 z_mask		equ	$04000000
274 inf_mask	equ	$02000000
275 nan_mask	equ	$01000000
276 *
277 bsun_mask	equ	$00008000
278 snan_mask	equ	$00004000
279 operr_mask	equ	$00002000
280 ovfl_mask	equ	$00001000
281 unfl_mask	equ	$00000800
282 dz_mask		equ	$00000400
283 inex2_mask	equ	$00000200
284 inex1_mask	equ	$00000100
285 *
286 aiop_mask	equ	$00000080	accrued illegal operation
287 aovfl_mask	equ	$00000040	accrued overflow
288 aunfl_mask	equ	$00000020	accrued underflow
289 adz_mask	equ	$00000010	accrued divide by zero
290 ainex_mask	equ	$00000008	accrued inexact
291 *
292 *	FPSR combinations used in the FPSP
293 *
294 dzinf_mask	equ	inf_mask+dz_mask+adz_mask
295 opnan_mask	equ	nan_mask+operr_mask+aiop_mask
296 nzi_mask	equ	$01ffffff 	clears N, Z, and I
297 unfinx_mask	equ	unfl_mask+inex2_mask+aunfl_mask+ainex_mask
298 unf2inx_mask	equ	unfl_mask+inex2_mask+ainex_mask
299 ovfinx_mask	equ	ovfl_mask+inex2_mask+aovfl_mask+ainex_mask
300 inx1a_mask	equ	inex1_mask+ainex_mask
301 inx2a_mask	equ	inex2_mask+ainex_mask
302 snaniop_mask	equ	nan_mask+snan_mask+aiop_mask
303 naniop_mask	equ	nan_mask+aiop_mask
304 neginf_mask	equ	neg_mask+inf_mask
305 infaiop_mask	equ	inf_mask+aiop_mask
306 negz_mask	equ	neg_mask+z_mask
307 opaop_mask	equ	operr_mask+aiop_mask
308 unfl_inx_mask	equ	unfl_mask+aunfl_mask+ainex_mask
309 ovfl_inx_mask	equ	ovfl_mask+aovfl_mask+ainex_mask
310 *
311 *--------------------------------------------------------------------------
312 *
313 *	FPCR rounding modes
314 *
315 x_mode		equ	$00	round to extended
316 s_mode		equ	$40	round to single
317 d_mode		equ	$80	round to double
318 *
319 rn_mode		equ	$00	round nearest
320 rz_mode		equ	$10	round to zero
321 rm_mode		equ	$20	round to minus infinity
322 rp_mode		equ	$30	round to plus infinity
323 *
324 *--------------------------------------------------------------------------
325 *
326 *	Miscellaneous equates
327 *
328 signan_bit	equ	6	signalling nan bit in mantissa
329 sign_bit	equ	7
330 *
331 rnd_stky_bit	equ	29	round/sticky bit of mantissa
332 *				this can only be used if in a data register
333 sx_mask		equ	$01800000 set s and x bits in word $48
334 *
335 LOCAL_EX	equ	0
336 LOCAL_SGN	equ	2
337 LOCAL_HI	equ	4
338 LOCAL_LO	equ	8
339 LOCAL_GRS	equ	12	valid ONLY for FP_SCR1, FP_SCR2
340 *
341 *
342 norm_tag	equ	$00	tag bits in {7:5} position
343 zero_tag	equ	$20
344 inf_tag		equ	$40
345 nan_tag		equ	$60
346 dnrm_tag	equ	$80
347 *
348 *	fsave sizes and formats
349 *
350 VER_4		equ	$40		fpsp compatible version numbers
351 *					are in the $40s {$40-$4f}
352 VER_40		equ	$40		original version number
353 VER_41		equ	$41		revision version number
354 *
355 BUSY_SIZE	equ	100		size of busy frame
356 BUSY_FRAME	equ	LV-BUSY_SIZE	start of busy frame
357 *
358 UNIMP_40_SIZE	equ	44		size of orig unimp frame
359 UNIMP_41_SIZE	equ	52		size of rev unimp frame
360 *
361 IDLE_SIZE	equ	4		size of idle frame
362 IDLE_FRAME	equ	LV-IDLE_SIZE	start of idle frame
363 *
364 *	exception vectors
365 *
366 TRACE_VEC	equ	$2024		trace trap
367 FLINE_VEC	equ	$002C		'real' F-line
368 UNIMP_VEC	equ	$202C		unimplemented
369 INEX_VEC	equ	$00C4
370 *
371 dbl_thresh	equ	$3C01
372 sgl_thresh	equ	$3F81
373 *
374