xref: /freebsd/sys/powerpc/booke/spe.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * Copyright (C) 1996 Wolfgang Solfrank.
3  * Copyright (C) 1996 TooLs GmbH.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by TooLs GmbH.
17  * 4. The name of TooLs GmbH may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
28  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
29  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  *	$NetBSD: fpu.c,v 1.5 2001/07/22 11:29:46 wiz Exp $
32  */
33 
34 #include <sys/cdefs.h>
35 #include <sys/param.h>
36 #include <sys/proc.h>
37 #include <sys/systm.h>
38 #include <sys/limits.h>
39 
40 #include <machine/altivec.h>
41 #include <machine/fpu.h>
42 #include <machine/ieeefp.h>
43 #include <machine/pcb.h>
44 #include <machine/psl.h>
45 
46 #include <powerpc/fpu/fpu_arith.h>
47 #include <powerpc/fpu/fpu_emu.h>
48 #include <powerpc/fpu/fpu_extern.h>
49 
50 void spe_handle_fpdata(struct trapframe *);
51 void spe_handle_fpround(struct trapframe *);
52 static int spe_emu_instr(uint32_t, struct fpemu *, struct fpn **, uint32_t *);
53 
54 static void
55 save_vec_int(struct thread *td)
56 {
57 	int	msr;
58 	struct	pcb *pcb;
59 
60 	pcb = td->td_pcb;
61 
62 	/*
63 	 * Temporarily re-enable the vector unit during the save
64 	 */
65 	msr = mfmsr();
66 	mtmsr(msr | PSL_VEC);
67 
68 	/*
69 	 * Save the vector registers and SPEFSCR to the PCB
70 	 */
71 #define EVSTDW(n)   __asm ("evstdw %1,0(%0)" \
72 		:: "b"(pcb->pcb_vec.vr[n]), "n"(n));
73 	EVSTDW(0);	EVSTDW(1);	EVSTDW(2);	EVSTDW(3);
74 	EVSTDW(4);	EVSTDW(5);	EVSTDW(6);	EVSTDW(7);
75 	EVSTDW(8);	EVSTDW(9);	EVSTDW(10);	EVSTDW(11);
76 	EVSTDW(12);	EVSTDW(13);	EVSTDW(14);	EVSTDW(15);
77 	EVSTDW(16);	EVSTDW(17);	EVSTDW(18);	EVSTDW(19);
78 	EVSTDW(20);	EVSTDW(21);	EVSTDW(22);	EVSTDW(23);
79 	EVSTDW(24);	EVSTDW(25);	EVSTDW(26);	EVSTDW(27);
80 	EVSTDW(28);	EVSTDW(29);	EVSTDW(30);	EVSTDW(31);
81 #undef EVSTDW
82 
83 	__asm ( "evxor 0,0,0\n"
84 		"evmwumiaa 0,0,0\n"
85 		"evstdd 0,0(%0)" :: "b"(&pcb->pcb_vec.spare[0]));
86 	pcb->pcb_vec.vscr = mfspr(SPR_SPEFSCR);
87 
88 	/*
89 	 * Disable vector unit again
90 	 */
91 	isync();
92 	mtmsr(msr);
93 
94 }
95 
96 void
97 enable_vec(struct thread *td)
98 {
99 	int	msr;
100 	struct	pcb *pcb;
101 	struct	trapframe *tf;
102 
103 	pcb = td->td_pcb;
104 	tf = trapframe(td);
105 
106 	/*
107 	 * Save the thread's SPE CPU number, and set the CPU's current
108 	 * vector thread
109 	 */
110 	td->td_pcb->pcb_veccpu = PCPU_GET(cpuid);
111 	PCPU_SET(vecthread, td);
112 
113 	/*
114 	 * Enable the vector unit for when the thread returns from the
115 	 * exception. If this is the first time the unit has been used by
116 	 * the thread, initialise the vector registers and VSCR to 0, and
117 	 * set the flag to indicate that the vector unit is in use.
118 	 */
119 	tf->srr1 |= PSL_VEC;
120 	if (!(pcb->pcb_flags & PCB_VEC)) {
121 		memset(&pcb->pcb_vec, 0, sizeof pcb->pcb_vec);
122 		pcb->pcb_flags |= PCB_VEC;
123 		pcb->pcb_vec.vscr = mfspr(SPR_SPEFSCR);
124 	}
125 
126 	/*
127 	 * Temporarily enable the vector unit so the registers
128 	 * can be restored.
129 	 */
130 	msr = mfmsr();
131 	mtmsr(msr | PSL_VEC);
132 
133 	/* Restore SPEFSCR and ACC.  Use %r0 as the scratch for ACC. */
134 	mtspr(SPR_SPEFSCR, pcb->pcb_vec.vscr);
135 	__asm __volatile("isync;evldd 0, 0(%0); evmra 0,0\n"
136 	    :: "b"(&pcb->pcb_vec.spare[0]));
137 
138 	/*
139 	 * The lower half of each register will be restored on trap return.  Use
140 	 * %r0 as a scratch register, and restore it last.
141 	 */
142 #define	EVLDW(n)   __asm __volatile("evldw 0, 0(%0); evmergehilo "#n",0,"#n \
143 	    :: "b"(&pcb->pcb_vec.vr[n]));
144 	EVLDW(1);	EVLDW(2);	EVLDW(3);	EVLDW(4);
145 	EVLDW(5);	EVLDW(6);	EVLDW(7);	EVLDW(8);
146 	EVLDW(9);	EVLDW(10);	EVLDW(11);	EVLDW(12);
147 	EVLDW(13);	EVLDW(14);	EVLDW(15);	EVLDW(16);
148 	EVLDW(17);	EVLDW(18);	EVLDW(19);	EVLDW(20);
149 	EVLDW(21);	EVLDW(22);	EVLDW(23);	EVLDW(24);
150 	EVLDW(25);	EVLDW(26);	EVLDW(27);	EVLDW(28);
151 	EVLDW(29);	EVLDW(30);	EVLDW(31);	EVLDW(0);
152 #undef EVLDW
153 
154 	isync();
155 	mtmsr(msr);
156 }
157 
158 void
159 save_vec(struct thread *td)
160 {
161 	struct pcb *pcb;
162 
163 	pcb = td->td_pcb;
164 
165 	save_vec_int(td);
166 
167 	/*
168 	 * Clear the current vec thread and pcb's CPU id
169 	 * XXX should this be left clear to allow lazy save/restore ?
170 	 */
171 	pcb->pcb_veccpu = INT_MAX;
172 	PCPU_SET(vecthread, NULL);
173 }
174 
175 /*
176  * Save SPE state without dropping ownership.  This will only save state if
177  * the current vector-thread is `td'.  This is used for taking core dumps, so
178  * don't leak kernel information; overwrite the low words of each vector with
179  * their real value, taken from the thread's trap frame, unconditionally.
180  */
181 void
182 save_vec_nodrop(struct thread *td)
183 {
184 	struct pcb *pcb;
185 	int i;
186 
187 	if (td == PCPU_GET(vecthread))
188 		save_vec_int(td);
189 
190 	pcb = td->td_pcb;
191 
192 	for (i = 0; i < 32; i++) {
193 		pcb->pcb_vec.vr[i][1] =
194 		    td->td_frame ? td->td_frame->fixreg[i] : 0;
195 	}
196 }
197 
198 #define	SPE_INST_MASK	0x31f
199 #define	EADD	0x200
200 #define	ESUB	0x201
201 #define	EABS	0x204
202 #define	ENABS	0x205
203 #define	ENEG	0x206
204 #define	EMUL	0x208
205 #define	EDIV	0x209
206 #define	ECMPGT	0x20c
207 #define	ECMPLT	0x20d
208 #define	ECMPEQ	0x20e
209 #define	ECFUI	0x210
210 #define	ECFSI	0x211
211 #define	ECTUI	0x214
212 #define	ECTSI	0x215
213 #define	ECTUF	0x216
214 #define	ECTSF	0x217
215 #define	ECTUIZ	0x218
216 #define	ECTSIZ	0x21a
217 
218 #define	SPE		0x4
219 #define	SPFP		0x6
220 #define	DPFP		0x7
221 
222 #define	SPE_OPC		4
223 #define	OPC_SHIFT	26
224 
225 #define	EVFSADD		0x280
226 #define	EVFSSUB		0x281
227 #define	EVFSABS		0x284
228 #define	EVFSNABS	0x285
229 #define	EVFSNEG		0x286
230 #define	EVFSMUL		0x288
231 #define	EVFSDIV		0x289
232 #define	EVFSCMPGT	0x28c
233 #define	EVFSCMPLT	0x28d
234 #define	EVFSCMPEQ	0x28e
235 #define	EVFSCFUI	0x290
236 #define	EVFSCFSI	0x291
237 #define	EVFSCTUI	0x294
238 #define	EVFSCTSI	0x295
239 #define	EVFSCTUF	0x296
240 #define	EVFSCTSF	0x297
241 #define	EVFSCTUIZ	0x298
242 #define	EVFSCTSIZ	0x29a
243 
244 #define	EFSADD		0x2c0
245 #define	EFSSUB		0x2c1
246 #define	EFSABS		0x2c4
247 #define	EFSNABS		0x2c5
248 #define	EFSNEG		0x2c6
249 #define	EFSMUL		0x2c8
250 #define	EFSDIV		0x2c9
251 #define	EFSCMPGT	0x2cc
252 #define	EFSCMPLT	0x2cd
253 #define	EFSCMPEQ	0x2ce
254 #define	EFSCFD		0x2cf
255 #define	EFSCFUI		0x2d0
256 #define	EFSCFSI		0x2d1
257 #define	EFSCTUI		0x2d4
258 #define	EFSCTSI		0x2d5
259 #define	EFSCTUF		0x2d6
260 #define	EFSCTSF		0x2d7
261 #define	EFSCTUIZ	0x2d8
262 #define	EFSCTSIZ	0x2da
263 
264 #define	EFDADD		0x2e0
265 #define	EFDSUB		0x2e1
266 #define	EFDABS		0x2e4
267 #define	EFDNABS		0x2e5
268 #define	EFDNEG		0x2e6
269 #define	EFDMUL		0x2e8
270 #define	EFDDIV		0x2e9
271 #define	EFDCMPGT	0x2ec
272 #define	EFDCMPLT	0x2ed
273 #define	EFDCMPEQ	0x2ee
274 #define	EFDCFS		0x2ef
275 #define	EFDCFUI		0x2f0
276 #define	EFDCFSI		0x2f1
277 #define	EFDCTUI		0x2f4
278 #define	EFDCTSI		0x2f5
279 #define	EFDCTUF		0x2f6
280 #define	EFDCTSF		0x2f7
281 #define	EFDCTUIZ	0x2f8
282 #define	EFDCTSIZ	0x2fa
283 
284 enum {
285 	NONE,
286 	SINGLE,
287 	DOUBLE,
288 	VECTOR,
289 };
290 
291 static uint32_t fpscr_to_spefscr(uint32_t fpscr)
292 {
293 	uint32_t spefscr;
294 
295 	spefscr = 0;
296 
297 	if (fpscr & FPSCR_VX)
298 		spefscr |= SPEFSCR_FINV;
299 	if (fpscr & FPSCR_OX)
300 		spefscr |= SPEFSCR_FOVF;
301 	if (fpscr & FPSCR_UX)
302 		spefscr |= SPEFSCR_FUNF;
303 	if (fpscr & FPSCR_ZX)
304 		spefscr |= SPEFSCR_FDBZ;
305 	if (fpscr & FPSCR_XX)
306 		spefscr |= SPEFSCR_FX;
307 
308 	return (spefscr);
309 }
310 
311 /* Sign is 0 for unsigned, 1 for signed. */
312 static int
313 spe_to_int(struct fpemu *fpemu, struct fpn *fpn, uint32_t *val, int sign)
314 {
315 	uint32_t res[2];
316 
317 	res[0] = fpu_ftox(fpemu, fpn, res);
318 	if (res[0] != UINT_MAX && res[0] != 0)
319 		fpemu->fe_cx |= FPSCR_OX;
320 	else if (sign == 0 && res[0] != 0)
321 		fpemu->fe_cx |= FPSCR_UX;
322 	else
323 		*val = res[1];
324 
325 	return (0);
326 }
327 
328 /* Masked instruction */
329 /*
330  * For compare instructions, returns 1 if success, 0 if not.  For all others,
331  * returns -1, or -2 if no result needs recorded.
332  */
333 static int
334 spe_emu_instr(uint32_t instr, struct fpemu *fpemu,
335     struct fpn **result, uint32_t *iresult)
336 {
337 	switch (instr & SPE_INST_MASK) {
338 	case EABS:
339 	case ENABS:
340 	case ENEG:
341 		/* Taken care of elsewhere. */
342 		break;
343 	case ECTUIZ:
344 		fpemu->fe_cx &= ~FPSCR_RN;
345 		fpemu->fe_cx |= FP_RZ;
346 	case ECTUI:
347 		spe_to_int(fpemu, &fpemu->fe_f2, iresult, 0);
348 		return (-1);
349 	case ECTSIZ:
350 		fpemu->fe_cx &= ~FPSCR_RN;
351 		fpemu->fe_cx |= FP_RZ;
352 	case ECTSI:
353 		spe_to_int(fpemu, &fpemu->fe_f2, iresult, 1);
354 		return (-1);
355 	case EADD:
356 		*result = fpu_add(fpemu);
357 		break;
358 	case ESUB:
359 		*result = fpu_sub(fpemu);
360 		break;
361 	case EMUL:
362 		*result = fpu_mul(fpemu);
363 		break;
364 	case EDIV:
365 		*result = fpu_div(fpemu);
366 		break;
367 	case ECMPGT:
368 		fpu_compare(fpemu, 0);
369 		if (fpemu->fe_cx & FPSCR_FG)
370 			return (1);
371 		return (0);
372 	case ECMPLT:
373 		fpu_compare(fpemu, 0);
374 		if (fpemu->fe_cx & FPSCR_FL)
375 			return (1);
376 		return (0);
377 	case ECMPEQ:
378 		fpu_compare(fpemu, 0);
379 		if (fpemu->fe_cx & FPSCR_FE)
380 			return (1);
381 		return (0);
382 	default:
383 		printf("Unknown instruction %x\n", instr);
384 	}
385 
386 	return (-1);
387 }
388 
389 static int
390 spe_explode(struct fpemu *fe, struct fpn *fp, uint32_t type,
391     uint32_t hi, uint32_t lo)
392 {
393 	uint32_t s;
394 
395 	fp->fp_sign = hi >> 31;
396 	fp->fp_sticky = 0;
397 	switch (type) {
398 	case SINGLE:
399 		s = fpu_stof(fp, hi);
400 		break;
401 
402 	case DOUBLE:
403 		s = fpu_dtof(fp, hi, lo);
404 		break;
405 	}
406 
407 	if (s == FPC_QNAN && (fp->fp_mant[0] & FP_QUIETBIT) == 0) {
408 		/*
409 		 * Input is a signalling NaN.  All operations that return
410 		 * an input NaN operand put it through a ``NaN conversion'',
411 		 * which basically just means ``turn on the quiet bit''.
412 		 * We do this here so that all NaNs internally look quiet
413 		 * (we can tell signalling ones by their class).
414 		 */
415 		fp->fp_mant[0] |= FP_QUIETBIT;
416 		fe->fe_cx = FPSCR_VXSNAN;	/* assert invalid operand */
417 		s = FPC_SNAN;
418 	}
419 	fp->fp_class = s;
420 
421 	return (0);
422 }
423 
424 /*
425  * Save the high word of a 64-bit GPR for manipulation in the exception handler.
426  */
427 static uint32_t
428 spe_save_reg_high(int reg)
429 {
430 	uint32_t vec[2];
431 #define EVSTDW(n)   case n: __asm __volatile ("evstdw %1,0(%0)" \
432 		:: "b"(vec), "n"(n) : "memory"); break;
433 	switch (reg) {
434 	EVSTDW(0);	EVSTDW(1);	EVSTDW(2);	EVSTDW(3);
435 	EVSTDW(4);	EVSTDW(5);	EVSTDW(6);	EVSTDW(7);
436 	EVSTDW(8);	EVSTDW(9);	EVSTDW(10);	EVSTDW(11);
437 	EVSTDW(12);	EVSTDW(13);	EVSTDW(14);	EVSTDW(15);
438 	EVSTDW(16);	EVSTDW(17);	EVSTDW(18);	EVSTDW(19);
439 	EVSTDW(20);	EVSTDW(21);	EVSTDW(22);	EVSTDW(23);
440 	EVSTDW(24);	EVSTDW(25);	EVSTDW(26);	EVSTDW(27);
441 	EVSTDW(28);	EVSTDW(29);	EVSTDW(30);	EVSTDW(31);
442 	}
443 #undef EVSTDW
444 
445 	return (vec[0]);
446 }
447 
448 /*
449  * Load the given value into the high word of the requested register.
450  */
451 static void
452 spe_load_reg_high(int reg, uint32_t val)
453 {
454 #define	EVLDW(n)   case n: __asm __volatile("evmergelo "#n",%0,"#n \
455 	    :: "r"(val)); break;
456 	switch (reg) {
457 	EVLDW(1);	EVLDW(2);	EVLDW(3);	EVLDW(4);
458 	EVLDW(5);	EVLDW(6);	EVLDW(7);	EVLDW(8);
459 	EVLDW(9);	EVLDW(10);	EVLDW(11);	EVLDW(12);
460 	EVLDW(13);	EVLDW(14);	EVLDW(15);	EVLDW(16);
461 	EVLDW(17);	EVLDW(18);	EVLDW(19);	EVLDW(20);
462 	EVLDW(21);	EVLDW(22);	EVLDW(23);	EVLDW(24);
463 	EVLDW(25);	EVLDW(26);	EVLDW(27);	EVLDW(28);
464 	EVLDW(29);	EVLDW(30);	EVLDW(31);	EVLDW(0);
465 	}
466 #undef EVLDW
467 
468 }
469 
470 void
471 spe_handle_fpdata(struct trapframe *frame)
472 {
473 	struct fpemu fpemu;
474 	struct fpn *result;
475 	uint32_t instr, instr_sec_op;
476 	uint32_t cr_shift, ra, rb, rd, src;
477 	uint32_t high, low, res, tmp; /* For vector operations. */
478 	uint32_t spefscr = 0;
479 	uint32_t ftod_res[2];
480 	int width; /* Single, Double, Vector, Integer */
481 	int err;
482 	uint32_t msr;
483 
484 	err = fueword32((void *)frame->srr0, &instr);
485 
486 	if (err != 0)
487 		return;
488 		/* Fault. */;
489 
490 	if ((instr >> OPC_SHIFT) != SPE_OPC)
491 		return;
492 
493 	msr = mfmsr();
494 	/*
495 	 * 'cr' field is the upper 3 bits of rd.  Magically, since a) rd is 5
496 	 * bits, b) each 'cr' field is 4 bits, and c) Only the 'GT' bit is
497 	 * modified for most compare operations, the full value of rd can be
498 	 * used as a shift value.
499 	 */
500 	rd = (instr >> 21) & 0x1f;
501 	ra = (instr >> 16) & 0x1f;
502 	rb = (instr >> 11) & 0x1f;
503 	src = (instr >> 5) & 0x7;
504 	cr_shift = 28 - (rd & 0x1f);
505 
506 	instr_sec_op = (instr & 0x7ff);
507 
508 	memset(&fpemu, 0, sizeof(fpemu));
509 
510 	width = NONE;
511 	switch (src) {
512 	case SPE:
513 		mtmsr(msr | PSL_VEC);
514 		switch (instr_sec_op) {
515 		case EVFSABS:
516 			high = spe_save_reg_high(ra) & ~(1U << 31);
517 			frame->fixreg[rd] = frame->fixreg[ra] & ~(1U << 31);
518 			spe_load_reg_high(rd, high);
519 			break;
520 		case EVFSNABS:
521 			high = spe_save_reg_high(ra) | (1U << 31);
522 			frame->fixreg[rd] = frame->fixreg[ra] | (1U << 31);
523 			spe_load_reg_high(rd, high);
524 			break;
525 		case EVFSNEG:
526 			high = spe_save_reg_high(ra) ^ (1U << 31);
527 			frame->fixreg[rd] = frame->fixreg[ra] ^ (1U << 31);
528 			spe_load_reg_high(rd, high);
529 			break;
530 		default:
531 			/* High word */
532 			spe_explode(&fpemu, &fpemu.fe_f1, SINGLE,
533 			    spe_save_reg_high(ra), 0);
534 			spe_explode(&fpemu, &fpemu.fe_f2, SINGLE,
535 			    spe_save_reg_high(rb), 0);
536 			high = spe_emu_instr(instr_sec_op, &fpemu, &result,
537 			    &tmp);
538 
539 			if (high < 0)
540 				spe_load_reg_high(rd, tmp);
541 
542 			spefscr = fpscr_to_spefscr(fpemu.fe_cx) << 16;
543 			/* Clear the fpemu to start over on the lower bits. */
544 			memset(&fpemu, 0, sizeof(fpemu));
545 
546 			/* Now low word */
547 			spe_explode(&fpemu, &fpemu.fe_f1, SINGLE,
548 			    frame->fixreg[ra], 0);
549 			spe_explode(&fpemu, &fpemu.fe_f2, SINGLE,
550 			    frame->fixreg[rb], 0);
551 			spefscr |= fpscr_to_spefscr(fpemu.fe_cx);
552 			low = spe_emu_instr(instr_sec_op, &fpemu, &result,
553 			    &frame->fixreg[rd]);
554 			if (instr_sec_op == EVFSCMPEQ ||
555 			    instr_sec_op == EVFSCMPGT ||
556 			    instr_sec_op == EVFSCMPLT) {
557 				res = (high << 3) | (low << 2) |
558 				    ((high | low) << 1) | (high & low);
559 				width = NONE;
560 			} else
561 				width = VECTOR;
562 			break;
563 		}
564 		goto end;
565 
566 	case SPFP:
567 		switch (instr_sec_op) {
568 		case EFSABS:
569 			frame->fixreg[rd] = frame->fixreg[ra] & ~(1U << 31);
570 			break;
571 		case EFSNABS:
572 			frame->fixreg[rd] = frame->fixreg[ra] | (1U << 31);
573 			break;
574 		case EFSNEG:
575 			frame->fixreg[rd] = frame->fixreg[ra] ^ (1U << 31);
576 			break;
577 		case EFSCFD:
578 			mtmsr(msr | PSL_VEC);
579 			spe_explode(&fpemu, &fpemu.fe_f3, DOUBLE,
580 			    spe_save_reg_high(rb), frame->fixreg[rb]);
581 			result = &fpemu.fe_f3;
582 			width = SINGLE;
583 			break;
584 		default:
585 			spe_explode(&fpemu, &fpemu.fe_f1, SINGLE,
586 			    frame->fixreg[ra], 0);
587 			spe_explode(&fpemu, &fpemu.fe_f2, SINGLE,
588 			    frame->fixreg[rb], 0);
589 			width = SINGLE;
590 		}
591 		break;
592 	case DPFP:
593 		mtmsr(msr | PSL_VEC);
594 		switch (instr_sec_op) {
595 		case EFDABS:
596 			high = spe_save_reg_high(ra) & ~(1U << 31);
597 			frame->fixreg[rd] = frame->fixreg[ra];
598 			spe_load_reg_high(rd, high);
599 			break;
600 		case EFDNABS:
601 			high = spe_save_reg_high(ra) | (1U << 31);
602 			frame->fixreg[rd] = frame->fixreg[ra];
603 			spe_load_reg_high(rd, high);
604 			break;
605 		case EFDNEG:
606 			high = spe_save_reg_high(ra) ^ (1U << 31);
607 			frame->fixreg[rd] = frame->fixreg[ra];
608 			spe_load_reg_high(rd, high);
609 			break;
610 		case EFDCFS:
611 			spe_explode(&fpemu, &fpemu.fe_f3, SINGLE,
612 			    frame->fixreg[rb], 0);
613 			result = &fpemu.fe_f3;
614 			width = DOUBLE;
615 			break;
616 		default:
617 			spe_explode(&fpemu, &fpemu.fe_f1, DOUBLE,
618 			    spe_save_reg_high(ra), frame->fixreg[ra]);
619 			spe_explode(&fpemu, &fpemu.fe_f2, DOUBLE,
620 			    spe_save_reg_high(rb), frame->fixreg[rb]);
621 			width = DOUBLE;
622 		}
623 		break;
624 	}
625 	switch (instr_sec_op) {
626 	case EFDCFS:
627 	case EFSCFD:
628 		/* Already handled. */
629 		break;
630 	default:
631 		res = spe_emu_instr(instr_sec_op, &fpemu, &result,
632 		    &frame->fixreg[rd]);
633 		if (res != -1)
634 			res <<= 2;
635 		break;
636 	}
637 
638 	switch (instr_sec_op & SPE_INST_MASK) {
639 	case ECMPEQ:
640 	case ECMPGT:
641 	case ECMPLT:
642 		frame->cr &= ~(0xf << cr_shift);
643 		frame->cr |= (res << cr_shift);
644 		break;
645 	case ECTUI:
646 	case ECTUIZ:
647 	case ECTSI:
648 	case ECTSIZ:
649 		break;
650 	default:
651 		switch (width) {
652 		case NONE:
653 		case VECTOR:
654 			break;
655 		case SINGLE:
656 			frame->fixreg[rd] = fpu_ftos(&fpemu, result);
657 			break;
658 		case DOUBLE:
659 			spe_load_reg_high(rd, fpu_ftod(&fpemu, result, ftod_res));
660 			frame->fixreg[rd] = ftod_res[1];
661 			break;
662 		default:
663 			panic("Unknown storage width %d", width);
664 			break;
665 		}
666 	}
667 
668 end:
669 	spefscr |= (mfspr(SPR_SPEFSCR) & ~SPEFSCR_FINVS);
670 	mtspr(SPR_SPEFSCR, spefscr);
671 	frame->srr0 += 4;
672 	mtmsr(msr);
673 
674 	return;
675 }
676 
677 void
678 spe_handle_fpround(struct trapframe *frame)
679 {
680 
681 	/*
682 	 * Punt fpround exceptions for now.  This leaves the truncated result in
683 	 * the register.  We'll deal with overflow/underflow later.
684 	 */
685 	return;
686 }
687