xref: /openbmc/linux/arch/sparc/kernel/visemul.c (revision fd589a8f)
1 /* visemul.c: Emulation of VIS instructions.
2  *
3  * Copyright (C) 2006 David S. Miller (davem@davemloft.net)
4  */
5 #include <linux/kernel.h>
6 #include <linux/errno.h>
7 #include <linux/thread_info.h>
8 
9 #include <asm/ptrace.h>
10 #include <asm/pstate.h>
11 #include <asm/system.h>
12 #include <asm/fpumacro.h>
13 #include <asm/uaccess.h>
14 
15 /* OPF field of various VIS instructions.  */
16 
17 /* 000111011 - four 16-bit packs  */
18 #define FPACK16_OPF	0x03b
19 
20 /* 000111010 - two 32-bit packs  */
21 #define FPACK32_OPF	0x03a
22 
23 /* 000111101 - four 16-bit packs  */
24 #define FPACKFIX_OPF	0x03d
25 
26 /* 001001101 - four 16-bit expands  */
27 #define FEXPAND_OPF	0x04d
28 
29 /* 001001011 - two 32-bit merges */
30 #define FPMERGE_OPF	0x04b
31 
32 /* 000110001 - 8-by-16-bit partitoned product  */
33 #define FMUL8x16_OPF	0x031
34 
35 /* 000110011 - 8-by-16-bit upper alpha partitioned product  */
36 #define FMUL8x16AU_OPF	0x033
37 
38 /* 000110101 - 8-by-16-bit lower alpha partitioned product  */
39 #define FMUL8x16AL_OPF	0x035
40 
41 /* 000110110 - upper 8-by-16-bit partitioned product  */
42 #define FMUL8SUx16_OPF	0x036
43 
44 /* 000110111 - lower 8-by-16-bit partitioned product  */
45 #define FMUL8ULx16_OPF	0x037
46 
47 /* 000111000 - upper 8-by-16-bit partitioned product  */
48 #define FMULD8SUx16_OPF	0x038
49 
50 /* 000111001 - lower unsigned 8-by-16-bit partitioned product  */
51 #define FMULD8ULx16_OPF	0x039
52 
53 /* 000101000 - four 16-bit compare; set rd if src1 > src2  */
54 #define FCMPGT16_OPF	0x028
55 
56 /* 000101100 - two 32-bit compare; set rd if src1 > src2  */
57 #define FCMPGT32_OPF	0x02c
58 
59 /* 000100000 - four 16-bit compare; set rd if src1 <= src2  */
60 #define FCMPLE16_OPF	0x020
61 
62 /* 000100100 - two 32-bit compare; set rd if src1 <= src2  */
63 #define FCMPLE32_OPF	0x024
64 
65 /* 000100010 - four 16-bit compare; set rd if src1 != src2  */
66 #define FCMPNE16_OPF	0x022
67 
68 /* 000100110 - two 32-bit compare; set rd if src1 != src2  */
69 #define FCMPNE32_OPF	0x026
70 
71 /* 000101010 - four 16-bit compare; set rd if src1 == src2  */
72 #define FCMPEQ16_OPF	0x02a
73 
74 /* 000101110 - two 32-bit compare; set rd if src1 == src2  */
75 #define FCMPEQ32_OPF	0x02e
76 
77 /* 000000000 - Eight 8-bit edge boundary processing  */
78 #define EDGE8_OPF	0x000
79 
80 /* 000000001 - Eight 8-bit edge boundary processing, no CC */
81 #define EDGE8N_OPF	0x001
82 
83 /* 000000010 - Eight 8-bit edge boundary processing, little-endian  */
84 #define EDGE8L_OPF	0x002
85 
86 /* 000000011 - Eight 8-bit edge boundary processing, little-endian, no CC  */
87 #define EDGE8LN_OPF	0x003
88 
89 /* 000000100 - Four 16-bit edge boundary processing  */
90 #define EDGE16_OPF	0x004
91 
92 /* 000000101 - Four 16-bit edge boundary processing, no CC  */
93 #define EDGE16N_OPF	0x005
94 
95 /* 000000110 - Four 16-bit edge boundary processing, little-endian  */
96 #define EDGE16L_OPF	0x006
97 
98 /* 000000111 - Four 16-bit edge boundary processing, little-endian, no CC  */
99 #define EDGE16LN_OPF	0x007
100 
101 /* 000001000 - Two 32-bit edge boundary processing  */
102 #define EDGE32_OPF	0x008
103 
104 /* 000001001 - Two 32-bit edge boundary processing, no CC  */
105 #define EDGE32N_OPF	0x009
106 
107 /* 000001010 - Two 32-bit edge boundary processing, little-endian  */
108 #define EDGE32L_OPF	0x00a
109 
110 /* 000001011 - Two 32-bit edge boundary processing, little-endian, no CC  */
111 #define EDGE32LN_OPF	0x00b
112 
113 /* 000111110 - distance between 8 8-bit components  */
114 #define PDIST_OPF	0x03e
115 
116 /* 000010000 - convert 8-bit 3-D address to blocked byte address  */
117 #define ARRAY8_OPF	0x010
118 
119 /* 000010010 - convert 16-bit 3-D address to blocked byte address  */
120 #define ARRAY16_OPF	0x012
121 
122 /* 000010100 - convert 32-bit 3-D address to blocked byte address  */
123 #define ARRAY32_OPF	0x014
124 
125 /* 000011001 - Set the GSR.MASK field in preparation for a BSHUFFLE  */
126 #define BMASK_OPF	0x019
127 
128 /* 001001100 - Permute bytes as specified by GSR.MASK  */
129 #define BSHUFFLE_OPF	0x04c
130 
131 #define VIS_OPF_SHIFT	5
132 #define VIS_OPF_MASK	(0x1ff << VIS_OPF_SHIFT)
133 
134 #define RS1(INSN)	(((INSN) >> 14) & 0x1f)
135 #define RS2(INSN)	(((INSN) >>  0) & 0x1f)
136 #define RD(INSN)	(((INSN) >> 25) & 0x1f)
137 
138 static inline void maybe_flush_windows(unsigned int rs1, unsigned int rs2,
139 				       unsigned int rd, int from_kernel)
140 {
141 	if (rs2 >= 16 || rs1 >= 16 || rd >= 16) {
142 		if (from_kernel != 0)
143 			__asm__ __volatile__("flushw");
144 		else
145 			flushw_user();
146 	}
147 }
148 
149 static unsigned long fetch_reg(unsigned int reg, struct pt_regs *regs)
150 {
151 	unsigned long value;
152 
153 	if (reg < 16)
154 		return (!reg ? 0 : regs->u_regs[reg]);
155 	if (regs->tstate & TSTATE_PRIV) {
156 		struct reg_window *win;
157 		win = (struct reg_window *)(regs->u_regs[UREG_FP] + STACK_BIAS);
158 		value = win->locals[reg - 16];
159 	} else if (test_thread_flag(TIF_32BIT)) {
160 		struct reg_window32 __user *win32;
161 		win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
162 		get_user(value, &win32->locals[reg - 16]);
163 	} else {
164 		struct reg_window __user *win;
165 		win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
166 		get_user(value, &win->locals[reg - 16]);
167 	}
168 	return value;
169 }
170 
171 static inline unsigned long __user *__fetch_reg_addr_user(unsigned int reg,
172 							  struct pt_regs *regs)
173 {
174 	BUG_ON(reg < 16);
175 	BUG_ON(regs->tstate & TSTATE_PRIV);
176 
177 	if (test_thread_flag(TIF_32BIT)) {
178 		struct reg_window32 __user *win32;
179 		win32 = (struct reg_window32 __user *)((unsigned long)((u32)regs->u_regs[UREG_FP]));
180 		return (unsigned long __user *)&win32->locals[reg - 16];
181 	} else {
182 		struct reg_window __user *win;
183 		win = (struct reg_window __user *)(regs->u_regs[UREG_FP] + STACK_BIAS);
184 		return &win->locals[reg - 16];
185 	}
186 }
187 
188 static inline unsigned long *__fetch_reg_addr_kern(unsigned int reg,
189 						   struct pt_regs *regs)
190 {
191 	BUG_ON(reg >= 16);
192 	BUG_ON(regs->tstate & TSTATE_PRIV);
193 
194 	return &regs->u_regs[reg];
195 }
196 
197 static void store_reg(struct pt_regs *regs, unsigned long val, unsigned long rd)
198 {
199 	if (rd < 16) {
200 		unsigned long *rd_kern = __fetch_reg_addr_kern(rd, regs);
201 
202 		*rd_kern = val;
203 	} else {
204 		unsigned long __user *rd_user = __fetch_reg_addr_user(rd, regs);
205 
206 		if (test_thread_flag(TIF_32BIT))
207 			__put_user((u32)val, (u32 __user *)rd_user);
208 		else
209 			__put_user(val, rd_user);
210 	}
211 }
212 
213 static inline unsigned long fpd_regval(struct fpustate *f,
214 				       unsigned int insn_regnum)
215 {
216 	insn_regnum = (((insn_regnum & 1) << 5) |
217 		       (insn_regnum & 0x1e));
218 
219 	return *(unsigned long *) &f->regs[insn_regnum];
220 }
221 
222 static inline unsigned long *fpd_regaddr(struct fpustate *f,
223 					 unsigned int insn_regnum)
224 {
225 	insn_regnum = (((insn_regnum & 1) << 5) |
226 		       (insn_regnum & 0x1e));
227 
228 	return (unsigned long *) &f->regs[insn_regnum];
229 }
230 
231 static inline unsigned int fps_regval(struct fpustate *f,
232 				      unsigned int insn_regnum)
233 {
234 	return f->regs[insn_regnum];
235 }
236 
237 static inline unsigned int *fps_regaddr(struct fpustate *f,
238 					unsigned int insn_regnum)
239 {
240 	return &f->regs[insn_regnum];
241 }
242 
243 struct edge_tab {
244 	u16 left, right;
245 };
246 static struct edge_tab edge8_tab[8] = {
247 	{ 0xff, 0x80 },
248 	{ 0x7f, 0xc0 },
249 	{ 0x3f, 0xe0 },
250 	{ 0x1f, 0xf0 },
251 	{ 0x0f, 0xf8 },
252 	{ 0x07, 0xfc },
253 	{ 0x03, 0xfe },
254 	{ 0x01, 0xff },
255 };
256 static struct edge_tab edge8_tab_l[8] = {
257 	{ 0xff, 0x01 },
258 	{ 0xfe, 0x03 },
259 	{ 0xfc, 0x07 },
260 	{ 0xf8, 0x0f },
261 	{ 0xf0, 0x1f },
262 	{ 0xe0, 0x3f },
263 	{ 0xc0, 0x7f },
264 	{ 0x80, 0xff },
265 };
266 static struct edge_tab edge16_tab[4] = {
267 	{ 0xf, 0x8 },
268 	{ 0x7, 0xc },
269 	{ 0x3, 0xe },
270 	{ 0x1, 0xf },
271 };
272 static struct edge_tab edge16_tab_l[4] = {
273 	{ 0xf, 0x1 },
274 	{ 0xe, 0x3 },
275 	{ 0xc, 0x7 },
276 	{ 0x8, 0xf },
277 };
278 static struct edge_tab edge32_tab[2] = {
279 	{ 0x3, 0x2 },
280 	{ 0x1, 0x3 },
281 };
282 static struct edge_tab edge32_tab_l[2] = {
283 	{ 0x3, 0x1 },
284 	{ 0x2, 0x3 },
285 };
286 
287 static void edge(struct pt_regs *regs, unsigned int insn, unsigned int opf)
288 {
289 	unsigned long orig_rs1, rs1, orig_rs2, rs2, rd_val;
290 	u16 left, right;
291 
292 	maybe_flush_windows(RS1(insn), RS2(insn), RD(insn), 0);
293 	orig_rs1 = rs1 = fetch_reg(RS1(insn), regs);
294 	orig_rs2 = rs2 = fetch_reg(RS2(insn), regs);
295 
296 	if (test_thread_flag(TIF_32BIT)) {
297 		rs1 = rs1 & 0xffffffff;
298 		rs2 = rs2 & 0xffffffff;
299 	}
300 	switch (opf) {
301 	default:
302 	case EDGE8_OPF:
303 	case EDGE8N_OPF:
304 		left = edge8_tab[rs1 & 0x7].left;
305 		right = edge8_tab[rs2 & 0x7].right;
306 		break;
307 	case EDGE8L_OPF:
308 	case EDGE8LN_OPF:
309 		left = edge8_tab_l[rs1 & 0x7].left;
310 		right = edge8_tab_l[rs2 & 0x7].right;
311 		break;
312 
313 	case EDGE16_OPF:
314 	case EDGE16N_OPF:
315 		left = edge16_tab[(rs1 >> 1) & 0x3].left;
316 		right = edge16_tab[(rs2 >> 1) & 0x3].right;
317 		break;
318 
319 	case EDGE16L_OPF:
320 	case EDGE16LN_OPF:
321 		left = edge16_tab_l[(rs1 >> 1) & 0x3].left;
322 		right = edge16_tab_l[(rs2 >> 1) & 0x3].right;
323 		break;
324 
325 	case EDGE32_OPF:
326 	case EDGE32N_OPF:
327 		left = edge32_tab[(rs1 >> 2) & 0x1].left;
328 		right = edge32_tab[(rs2 >> 2) & 0x1].right;
329 		break;
330 
331 	case EDGE32L_OPF:
332 	case EDGE32LN_OPF:
333 		left = edge32_tab_l[(rs1 >> 2) & 0x1].left;
334 		right = edge32_tab_l[(rs2 >> 2) & 0x1].right;
335 		break;
336 	};
337 
338 	if ((rs1 & ~0x7UL) == (rs2 & ~0x7UL))
339 		rd_val = right & left;
340 	else
341 		rd_val = left;
342 
343 	store_reg(regs, rd_val, RD(insn));
344 
345 	switch (opf) {
346 	case EDGE8_OPF:
347 	case EDGE8L_OPF:
348 	case EDGE16_OPF:
349 	case EDGE16L_OPF:
350 	case EDGE32_OPF:
351 	case EDGE32L_OPF: {
352 		unsigned long ccr, tstate;
353 
354 		__asm__ __volatile__("subcc	%1, %2, %%g0\n\t"
355 				     "rd	%%ccr, %0"
356 				     : "=r" (ccr)
357 				     : "r" (orig_rs1), "r" (orig_rs2)
358 				     : "cc");
359 		tstate = regs->tstate & ~(TSTATE_XCC | TSTATE_ICC);
360 		regs->tstate = tstate | (ccr << 32UL);
361 	}
362 	};
363 }
364 
365 static void array(struct pt_regs *regs, unsigned int insn, unsigned int opf)
366 {
367 	unsigned long rs1, rs2, rd_val;
368 	unsigned int bits, bits_mask;
369 
370 	maybe_flush_windows(RS1(insn), RS2(insn), RD(insn), 0);
371 	rs1 = fetch_reg(RS1(insn), regs);
372 	rs2 = fetch_reg(RS2(insn), regs);
373 
374 	bits = (rs2 > 5 ? 5 : rs2);
375 	bits_mask = (1UL << bits) - 1UL;
376 
377 	rd_val = ((((rs1 >> 11) & 0x3) <<  0) |
378 		  (((rs1 >> 33) & 0x3) <<  2) |
379 		  (((rs1 >> 55) & 0x1) <<  4) |
380 		  (((rs1 >> 13) & 0xf) <<  5) |
381 		  (((rs1 >> 35) & 0xf) <<  9) |
382 		  (((rs1 >> 56) & 0xf) << 13) |
383 		  (((rs1 >> 17) & bits_mask) << 17) |
384 		  (((rs1 >> 39) & bits_mask) << (17 + bits)) |
385 		  (((rs1 >> 60) & 0xf)       << (17 + (2*bits))));
386 
387 	switch (opf) {
388 	case ARRAY16_OPF:
389 		rd_val <<= 1;
390 		break;
391 
392 	case ARRAY32_OPF:
393 		rd_val <<= 2;
394 	};
395 
396 	store_reg(regs, rd_val, RD(insn));
397 }
398 
399 static void bmask(struct pt_regs *regs, unsigned int insn)
400 {
401 	unsigned long rs1, rs2, rd_val, gsr;
402 
403 	maybe_flush_windows(RS1(insn), RS2(insn), RD(insn), 0);
404 	rs1 = fetch_reg(RS1(insn), regs);
405 	rs2 = fetch_reg(RS2(insn), regs);
406 	rd_val = rs1 + rs2;
407 
408 	store_reg(regs, rd_val, RD(insn));
409 
410 	gsr = current_thread_info()->gsr[0] & 0xffffffff;
411 	gsr |= rd_val << 32UL;
412 	current_thread_info()->gsr[0] = gsr;
413 }
414 
415 static void bshuffle(struct pt_regs *regs, unsigned int insn)
416 {
417 	struct fpustate *f = FPUSTATE;
418 	unsigned long rs1, rs2, rd_val;
419 	unsigned long bmask, i;
420 
421 	bmask = current_thread_info()->gsr[0] >> 32UL;
422 
423 	rs1 = fpd_regval(f, RS1(insn));
424 	rs2 = fpd_regval(f, RS2(insn));
425 
426 	rd_val = 0UL;
427 	for (i = 0; i < 8; i++) {
428 		unsigned long which = (bmask >> (i * 4)) & 0xf;
429 		unsigned long byte;
430 
431 		if (which < 8)
432 			byte = (rs1 >> (which * 8)) & 0xff;
433 		else
434 			byte = (rs2 >> ((which-8)*8)) & 0xff;
435 		rd_val |= (byte << (i * 8));
436 	}
437 
438 	*fpd_regaddr(f, RD(insn)) = rd_val;
439 }
440 
441 static void pdist(struct pt_regs *regs, unsigned int insn)
442 {
443 	struct fpustate *f = FPUSTATE;
444 	unsigned long rs1, rs2, *rd, rd_val;
445 	unsigned long i;
446 
447 	rs1 = fpd_regval(f, RS1(insn));
448 	rs2 = fpd_regval(f, RS2(insn));
449 	rd = fpd_regaddr(f, RD(insn));
450 
451 	rd_val = *rd;
452 
453 	for (i = 0; i < 8; i++) {
454 		s16 s1, s2;
455 
456 		s1 = (rs1 >> (56 - (i * 8))) & 0xff;
457 		s2 = (rs2 >> (56 - (i * 8))) & 0xff;
458 
459 		/* Absolute value of difference. */
460 		s1 -= s2;
461 		if (s1 < 0)
462 			s1 = ~s1 + 1;
463 
464 		rd_val += s1;
465 	}
466 
467 	*rd = rd_val;
468 }
469 
470 static void pformat(struct pt_regs *regs, unsigned int insn, unsigned int opf)
471 {
472 	struct fpustate *f = FPUSTATE;
473 	unsigned long rs1, rs2, gsr, scale, rd_val;
474 
475 	gsr = current_thread_info()->gsr[0];
476 	scale = (gsr >> 3) & (opf == FPACK16_OPF ? 0xf : 0x1f);
477 	switch (opf) {
478 	case FPACK16_OPF: {
479 		unsigned long byte;
480 
481 		rs2 = fpd_regval(f, RS2(insn));
482 		rd_val = 0;
483 		for (byte = 0; byte < 4; byte++) {
484 			unsigned int val;
485 			s16 src = (rs2 >> (byte * 16UL)) & 0xffffUL;
486 			int scaled = src << scale;
487 			int from_fixed = scaled >> 7;
488 
489 			val = ((from_fixed < 0) ?
490 			       0 :
491 			       (from_fixed > 255) ?
492 			       255 : from_fixed);
493 
494 			rd_val |= (val << (8 * byte));
495 		}
496 		*fps_regaddr(f, RD(insn)) = rd_val;
497 		break;
498 	}
499 
500 	case FPACK32_OPF: {
501 		unsigned long word;
502 
503 		rs1 = fpd_regval(f, RS1(insn));
504 		rs2 = fpd_regval(f, RS2(insn));
505 		rd_val = (rs1 << 8) & ~(0x000000ff000000ffUL);
506 		for (word = 0; word < 2; word++) {
507 			unsigned long val;
508 			s32 src = (rs2 >> (word * 32UL));
509 			s64 scaled = src << scale;
510 			s64 from_fixed = scaled >> 23;
511 
512 			val = ((from_fixed < 0) ?
513 			       0 :
514 			       (from_fixed > 255) ?
515 			       255 : from_fixed);
516 
517 			rd_val |= (val << (32 * word));
518 		}
519 		*fpd_regaddr(f, RD(insn)) = rd_val;
520 		break;
521 	}
522 
523 	case FPACKFIX_OPF: {
524 		unsigned long word;
525 
526 		rs2 = fpd_regval(f, RS2(insn));
527 
528 		rd_val = 0;
529 		for (word = 0; word < 2; word++) {
530 			long val;
531 			s32 src = (rs2 >> (word * 32UL));
532 			s64 scaled = src << scale;
533 			s64 from_fixed = scaled >> 16;
534 
535 			val = ((from_fixed < -32768) ?
536 			       -32768 :
537 			       (from_fixed > 32767) ?
538 			       32767 : from_fixed);
539 
540 			rd_val |= ((val & 0xffff) << (word * 16));
541 		}
542 		*fps_regaddr(f, RD(insn)) = rd_val;
543 		break;
544 	}
545 
546 	case FEXPAND_OPF: {
547 		unsigned long byte;
548 
549 		rs2 = fps_regval(f, RS2(insn));
550 
551 		rd_val = 0;
552 		for (byte = 0; byte < 4; byte++) {
553 			unsigned long val;
554 			u8 src = (rs2 >> (byte * 8)) & 0xff;
555 
556 			val = src << 4;
557 
558 			rd_val |= (val << (byte * 16));
559 		}
560 		*fpd_regaddr(f, RD(insn)) = rd_val;
561 		break;
562 	}
563 
564 	case FPMERGE_OPF: {
565 		rs1 = fps_regval(f, RS1(insn));
566 		rs2 = fps_regval(f, RS2(insn));
567 
568 		rd_val = (((rs2 & 0x000000ff) <<  0) |
569 			  ((rs1 & 0x000000ff) <<  8) |
570 			  ((rs2 & 0x0000ff00) <<  8) |
571 			  ((rs1 & 0x0000ff00) << 16) |
572 			  ((rs2 & 0x00ff0000) << 16) |
573 			  ((rs1 & 0x00ff0000) << 24) |
574 			  ((rs2 & 0xff000000) << 24) |
575 			  ((rs1 & 0xff000000) << 32));
576 		*fpd_regaddr(f, RD(insn)) = rd_val;
577 		break;
578 	}
579 	};
580 }
581 
582 static void pmul(struct pt_regs *regs, unsigned int insn, unsigned int opf)
583 {
584 	struct fpustate *f = FPUSTATE;
585 	unsigned long rs1, rs2, rd_val;
586 
587 	switch (opf) {
588 	case FMUL8x16_OPF: {
589 		unsigned long byte;
590 
591 		rs1 = fps_regval(f, RS1(insn));
592 		rs2 = fpd_regval(f, RS2(insn));
593 
594 		rd_val = 0;
595 		for (byte = 0; byte < 4; byte++) {
596 			u16 src1 = (rs1 >> (byte *  8)) & 0x00ff;
597 			s16 src2 = (rs2 >> (byte * 16)) & 0xffff;
598 			u32 prod = src1 * src2;
599 			u16 scaled = ((prod & 0x00ffff00) >> 8);
600 
601 			/* Round up.  */
602 			if (prod & 0x80)
603 				scaled++;
604 			rd_val |= ((scaled & 0xffffUL) << (byte * 16UL));
605 		}
606 
607 		*fpd_regaddr(f, RD(insn)) = rd_val;
608 		break;
609 	}
610 
611 	case FMUL8x16AU_OPF:
612 	case FMUL8x16AL_OPF: {
613 		unsigned long byte;
614 		s16 src2;
615 
616 		rs1 = fps_regval(f, RS1(insn));
617 		rs2 = fps_regval(f, RS2(insn));
618 
619 		rd_val = 0;
620 		src2 = (rs2 >> (opf == FMUL8x16AU_OPF) ? 16 : 0);
621 		for (byte = 0; byte < 4; byte++) {
622 			u16 src1 = (rs1 >> (byte * 8)) & 0x00ff;
623 			u32 prod = src1 * src2;
624 			u16 scaled = ((prod & 0x00ffff00) >> 8);
625 
626 			/* Round up.  */
627 			if (prod & 0x80)
628 				scaled++;
629 			rd_val |= ((scaled & 0xffffUL) << (byte * 16UL));
630 		}
631 
632 		*fpd_regaddr(f, RD(insn)) = rd_val;
633 		break;
634 	}
635 
636 	case FMUL8SUx16_OPF:
637 	case FMUL8ULx16_OPF: {
638 		unsigned long byte, ushift;
639 
640 		rs1 = fpd_regval(f, RS1(insn));
641 		rs2 = fpd_regval(f, RS2(insn));
642 
643 		rd_val = 0;
644 		ushift = (opf == FMUL8SUx16_OPF) ? 8 : 0;
645 		for (byte = 0; byte < 4; byte++) {
646 			u16 src1;
647 			s16 src2;
648 			u32 prod;
649 			u16 scaled;
650 
651 			src1 = ((rs1 >> ((16 * byte) + ushift)) & 0x00ff);
652 			src2 = ((rs2 >> (16 * byte)) & 0xffff);
653 			prod = src1 * src2;
654 			scaled = ((prod & 0x00ffff00) >> 8);
655 
656 			/* Round up.  */
657 			if (prod & 0x80)
658 				scaled++;
659 			rd_val |= ((scaled & 0xffffUL) << (byte * 16UL));
660 		}
661 
662 		*fpd_regaddr(f, RD(insn)) = rd_val;
663 		break;
664 	}
665 
666 	case FMULD8SUx16_OPF:
667 	case FMULD8ULx16_OPF: {
668 		unsigned long byte, ushift;
669 
670 		rs1 = fps_regval(f, RS1(insn));
671 		rs2 = fps_regval(f, RS2(insn));
672 
673 		rd_val = 0;
674 		ushift = (opf == FMULD8SUx16_OPF) ? 8 : 0;
675 		for (byte = 0; byte < 2; byte++) {
676 			u16 src1;
677 			s16 src2;
678 			u32 prod;
679 			u16 scaled;
680 
681 			src1 = ((rs1 >> ((16 * byte) + ushift)) & 0x00ff);
682 			src2 = ((rs2 >> (16 * byte)) & 0xffff);
683 			prod = src1 * src2;
684 			scaled = ((prod & 0x00ffff00) >> 8);
685 
686 			/* Round up.  */
687 			if (prod & 0x80)
688 				scaled++;
689 			rd_val |= ((scaled & 0xffffUL) <<
690 				   ((byte * 32UL) + 7UL));
691 		}
692 		*fpd_regaddr(f, RD(insn)) = rd_val;
693 		break;
694 	}
695 	};
696 }
697 
698 static void pcmp(struct pt_regs *regs, unsigned int insn, unsigned int opf)
699 {
700 	struct fpustate *f = FPUSTATE;
701 	unsigned long rs1, rs2, rd_val, i;
702 
703 	rs1 = fpd_regval(f, RS1(insn));
704 	rs2 = fpd_regval(f, RS2(insn));
705 
706 	rd_val = 0;
707 
708 	switch (opf) {
709 	case FCMPGT16_OPF:
710 		for (i = 0; i < 4; i++) {
711 			s16 a = (rs1 >> (i * 16)) & 0xffff;
712 			s16 b = (rs2 >> (i * 16)) & 0xffff;
713 
714 			if (a > b)
715 				rd_val |= 1 << i;
716 		}
717 		break;
718 
719 	case FCMPGT32_OPF:
720 		for (i = 0; i < 2; i++) {
721 			s32 a = (rs1 >> (i * 32)) & 0xffff;
722 			s32 b = (rs2 >> (i * 32)) & 0xffff;
723 
724 			if (a > b)
725 				rd_val |= 1 << i;
726 		}
727 		break;
728 
729 	case FCMPLE16_OPF:
730 		for (i = 0; i < 4; i++) {
731 			s16 a = (rs1 >> (i * 16)) & 0xffff;
732 			s16 b = (rs2 >> (i * 16)) & 0xffff;
733 
734 			if (a <= b)
735 				rd_val |= 1 << i;
736 		}
737 		break;
738 
739 	case FCMPLE32_OPF:
740 		for (i = 0; i < 2; i++) {
741 			s32 a = (rs1 >> (i * 32)) & 0xffff;
742 			s32 b = (rs2 >> (i * 32)) & 0xffff;
743 
744 			if (a <= b)
745 				rd_val |= 1 << i;
746 		}
747 		break;
748 
749 	case FCMPNE16_OPF:
750 		for (i = 0; i < 4; i++) {
751 			s16 a = (rs1 >> (i * 16)) & 0xffff;
752 			s16 b = (rs2 >> (i * 16)) & 0xffff;
753 
754 			if (a != b)
755 				rd_val |= 1 << i;
756 		}
757 		break;
758 
759 	case FCMPNE32_OPF:
760 		for (i = 0; i < 2; i++) {
761 			s32 a = (rs1 >> (i * 32)) & 0xffff;
762 			s32 b = (rs2 >> (i * 32)) & 0xffff;
763 
764 			if (a != b)
765 				rd_val |= 1 << i;
766 		}
767 		break;
768 
769 	case FCMPEQ16_OPF:
770 		for (i = 0; i < 4; i++) {
771 			s16 a = (rs1 >> (i * 16)) & 0xffff;
772 			s16 b = (rs2 >> (i * 16)) & 0xffff;
773 
774 			if (a == b)
775 				rd_val |= 1 << i;
776 		}
777 		break;
778 
779 	case FCMPEQ32_OPF:
780 		for (i = 0; i < 2; i++) {
781 			s32 a = (rs1 >> (i * 32)) & 0xffff;
782 			s32 b = (rs2 >> (i * 32)) & 0xffff;
783 
784 			if (a == b)
785 				rd_val |= 1 << i;
786 		}
787 		break;
788 	};
789 
790 	maybe_flush_windows(0, 0, RD(insn), 0);
791 	store_reg(regs, rd_val, RD(insn));
792 }
793 
794 /* Emulate the VIS instructions which are not implemented in
795  * hardware on Niagara.
796  */
797 int vis_emul(struct pt_regs *regs, unsigned int insn)
798 {
799 	unsigned long pc = regs->tpc;
800 	unsigned int opf;
801 
802 	BUG_ON(regs->tstate & TSTATE_PRIV);
803 
804 	if (test_thread_flag(TIF_32BIT))
805 		pc = (u32)pc;
806 
807 	if (get_user(insn, (u32 __user *) pc))
808 		return -EFAULT;
809 
810 	save_and_clear_fpu();
811 
812 	opf = (insn & VIS_OPF_MASK) >> VIS_OPF_SHIFT;
813 	switch (opf) {
814 	default:
815 		return -EINVAL;
816 
817 	/* Pixel Formatting Instructions.  */
818 	case FPACK16_OPF:
819 	case FPACK32_OPF:
820 	case FPACKFIX_OPF:
821 	case FEXPAND_OPF:
822 	case FPMERGE_OPF:
823 		pformat(regs, insn, opf);
824 		break;
825 
826 	/* Partitioned Multiply Instructions  */
827 	case FMUL8x16_OPF:
828 	case FMUL8x16AU_OPF:
829 	case FMUL8x16AL_OPF:
830 	case FMUL8SUx16_OPF:
831 	case FMUL8ULx16_OPF:
832 	case FMULD8SUx16_OPF:
833 	case FMULD8ULx16_OPF:
834 		pmul(regs, insn, opf);
835 		break;
836 
837 	/* Pixel Compare Instructions  */
838 	case FCMPGT16_OPF:
839 	case FCMPGT32_OPF:
840 	case FCMPLE16_OPF:
841 	case FCMPLE32_OPF:
842 	case FCMPNE16_OPF:
843 	case FCMPNE32_OPF:
844 	case FCMPEQ16_OPF:
845 	case FCMPEQ32_OPF:
846 		pcmp(regs, insn, opf);
847 		break;
848 
849 	/* Edge Handling Instructions  */
850 	case EDGE8_OPF:
851 	case EDGE8N_OPF:
852 	case EDGE8L_OPF:
853 	case EDGE8LN_OPF:
854 	case EDGE16_OPF:
855 	case EDGE16N_OPF:
856 	case EDGE16L_OPF:
857 	case EDGE16LN_OPF:
858 	case EDGE32_OPF:
859 	case EDGE32N_OPF:
860 	case EDGE32L_OPF:
861 	case EDGE32LN_OPF:
862 		edge(regs, insn, opf);
863 		break;
864 
865 	/* Pixel Component Distance  */
866 	case PDIST_OPF:
867 		pdist(regs, insn);
868 		break;
869 
870 	/* Three-Dimensional Array Addressing Instructions  */
871 	case ARRAY8_OPF:
872 	case ARRAY16_OPF:
873 	case ARRAY32_OPF:
874 		array(regs, insn, opf);
875 		break;
876 
877 	/* Byte Mask and Shuffle Instructions  */
878 	case BMASK_OPF:
879 		bmask(regs, insn);
880 		break;
881 
882 	case BSHUFFLE_OPF:
883 		bshuffle(regs, insn);
884 		break;
885 	};
886 
887 	regs->tpc = regs->tnpc;
888 	regs->tnpc += 4;
889 	return 0;
890 }
891