xref: /openbmc/linux/arch/parisc/kernel/unaligned.c (revision 0c874100)
1 /*
2  *    Unaligned memory access handler
3  *
4  *    Copyright (C) 2001 Randolph Chung <tausq@debian.org>
5  *    Significantly tweaked by LaMont Jones <lamont@debian.org>
6  *
7  *    This program is free software; you can redistribute it and/or modify
8  *    it under the terms of the GNU General Public License as published by
9  *    the Free Software Foundation; either version 2, or (at your option)
10  *    any later version.
11  *
12  *    This program is distributed in the hope that it will be useful,
13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *    GNU General Public License for more details.
16  *
17  *    You should have received a copy of the GNU General Public License
18  *    along with this program; if not, write to the Free Software
19  *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  *
21  */
22 
23 #include <linux/jiffies.h>
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/sched/signal.h>
27 #include <linux/sched/debug.h>
28 #include <linux/signal.h>
29 #include <linux/ratelimit.h>
30 #include <linux/uaccess.h>
31 #include <asm/hardirq.h>
32 #include <asm/traps.h>
33 
34 /* #define DEBUG_UNALIGNED 1 */
35 
36 #ifdef DEBUG_UNALIGNED
37 #define DPRINTF(fmt, args...) do { printk(KERN_DEBUG "%s:%d:%s ", __FILE__, __LINE__, __func__ ); printk(KERN_DEBUG fmt, ##args ); } while (0)
38 #else
39 #define DPRINTF(fmt, args...)
40 #endif
41 
42 #ifdef CONFIG_64BIT
43 #define RFMT "%016lx"
44 #else
45 #define RFMT "%08lx"
46 #endif
47 
48 #define FIXUP_BRANCH(lbl) \
49 	"\tldil L%%" #lbl ", %%r1\n"			\
50 	"\tldo R%%" #lbl "(%%r1), %%r1\n"		\
51 	"\tbv,n %%r0(%%r1)\n"
52 /* If you use FIXUP_BRANCH, then you must list this clobber */
53 #define FIXUP_BRANCH_CLOBBER "r1"
54 
55 /* 1111 1100 0000 0000 0001 0011 1100 0000 */
56 #define OPCODE1(a,b,c)	((a)<<26|(b)<<12|(c)<<6)
57 #define OPCODE2(a,b)	((a)<<26|(b)<<1)
58 #define OPCODE3(a,b)	((a)<<26|(b)<<2)
59 #define OPCODE4(a)	((a)<<26)
60 #define OPCODE1_MASK	OPCODE1(0x3f,1,0xf)
61 #define OPCODE2_MASK 	OPCODE2(0x3f,1)
62 #define OPCODE3_MASK	OPCODE3(0x3f,1)
63 #define OPCODE4_MASK    OPCODE4(0x3f)
64 
65 /* skip LDB - never unaligned (index) */
66 #define OPCODE_LDH_I	OPCODE1(0x03,0,0x1)
67 #define OPCODE_LDW_I	OPCODE1(0x03,0,0x2)
68 #define OPCODE_LDD_I	OPCODE1(0x03,0,0x3)
69 #define OPCODE_LDDA_I	OPCODE1(0x03,0,0x4)
70 #define OPCODE_LDCD_I	OPCODE1(0x03,0,0x5)
71 #define OPCODE_LDWA_I	OPCODE1(0x03,0,0x6)
72 #define OPCODE_LDCW_I	OPCODE1(0x03,0,0x7)
73 /* skip LDB - never unaligned (short) */
74 #define OPCODE_LDH_S	OPCODE1(0x03,1,0x1)
75 #define OPCODE_LDW_S	OPCODE1(0x03,1,0x2)
76 #define OPCODE_LDD_S	OPCODE1(0x03,1,0x3)
77 #define OPCODE_LDDA_S	OPCODE1(0x03,1,0x4)
78 #define OPCODE_LDCD_S	OPCODE1(0x03,1,0x5)
79 #define OPCODE_LDWA_S	OPCODE1(0x03,1,0x6)
80 #define OPCODE_LDCW_S	OPCODE1(0x03,1,0x7)
81 /* skip STB - never unaligned */
82 #define OPCODE_STH	OPCODE1(0x03,1,0x9)
83 #define OPCODE_STW	OPCODE1(0x03,1,0xa)
84 #define OPCODE_STD	OPCODE1(0x03,1,0xb)
85 /* skip STBY - never unaligned */
86 /* skip STDBY - never unaligned */
87 #define OPCODE_STWA	OPCODE1(0x03,1,0xe)
88 #define OPCODE_STDA	OPCODE1(0x03,1,0xf)
89 
90 #define OPCODE_FLDWX	OPCODE1(0x09,0,0x0)
91 #define OPCODE_FLDWXR	OPCODE1(0x09,0,0x1)
92 #define OPCODE_FSTWX	OPCODE1(0x09,0,0x8)
93 #define OPCODE_FSTWXR	OPCODE1(0x09,0,0x9)
94 #define OPCODE_FLDWS	OPCODE1(0x09,1,0x0)
95 #define OPCODE_FLDWSR	OPCODE1(0x09,1,0x1)
96 #define OPCODE_FSTWS	OPCODE1(0x09,1,0x8)
97 #define OPCODE_FSTWSR	OPCODE1(0x09,1,0x9)
98 #define OPCODE_FLDDX	OPCODE1(0x0b,0,0x0)
99 #define OPCODE_FSTDX	OPCODE1(0x0b,0,0x8)
100 #define OPCODE_FLDDS	OPCODE1(0x0b,1,0x0)
101 #define OPCODE_FSTDS	OPCODE1(0x0b,1,0x8)
102 
103 #define OPCODE_LDD_L	OPCODE2(0x14,0)
104 #define OPCODE_FLDD_L	OPCODE2(0x14,1)
105 #define OPCODE_STD_L	OPCODE2(0x1c,0)
106 #define OPCODE_FSTD_L	OPCODE2(0x1c,1)
107 
108 #define OPCODE_LDW_M	OPCODE3(0x17,1)
109 #define OPCODE_FLDW_L	OPCODE3(0x17,0)
110 #define OPCODE_FSTW_L	OPCODE3(0x1f,0)
111 #define OPCODE_STW_M	OPCODE3(0x1f,1)
112 
113 #define OPCODE_LDH_L    OPCODE4(0x11)
114 #define OPCODE_LDW_L    OPCODE4(0x12)
115 #define OPCODE_LDWM     OPCODE4(0x13)
116 #define OPCODE_STH_L    OPCODE4(0x19)
117 #define OPCODE_STW_L    OPCODE4(0x1A)
118 #define OPCODE_STWM     OPCODE4(0x1B)
119 
120 #define MAJOR_OP(i) (((i)>>26)&0x3f)
121 #define R1(i) (((i)>>21)&0x1f)
122 #define R2(i) (((i)>>16)&0x1f)
123 #define R3(i) ((i)&0x1f)
124 #define FR3(i) ((((i)<<1)&0x1f)|(((i)>>6)&1))
125 #define IM(i,n) (((i)>>1&((1<<(n-1))-1))|((i)&1?((0-1L)<<(n-1)):0))
126 #define IM5_2(i) IM((i)>>16,5)
127 #define IM5_3(i) IM((i),5)
128 #define IM14(i) IM((i),14)
129 
130 #define ERR_NOTHANDLED	-1
131 #define ERR_PAGEFAULT	-2
132 
133 int unaligned_enabled __read_mostly = 1;
134 
135 static int emulate_ldh(struct pt_regs *regs, int toreg)
136 {
137 	unsigned long saddr = regs->ior;
138 	unsigned long val = 0;
139 	int ret;
140 
141 	DPRINTF("load " RFMT ":" RFMT " to r%d for 2 bytes\n",
142 		regs->isr, regs->ior, toreg);
143 
144 	__asm__ __volatile__  (
145 "	mtsp	%4, %%sr1\n"
146 "1:	ldbs	0(%%sr1,%3), %%r20\n"
147 "2:	ldbs	1(%%sr1,%3), %0\n"
148 "	depw	%%r20, 23, 24, %0\n"
149 "	copy	%%r0, %1\n"
150 "3:	\n"
151 "	.section .fixup,\"ax\"\n"
152 "4:	ldi	-2, %1\n"
153 	FIXUP_BRANCH(3b)
154 "	.previous\n"
155 	ASM_EXCEPTIONTABLE_ENTRY(1b, 4b)
156 	ASM_EXCEPTIONTABLE_ENTRY(2b, 4b)
157 	: "=r" (val), "=r" (ret)
158 	: "0" (val), "r" (saddr), "r" (regs->isr)
159 	: "r20", FIXUP_BRANCH_CLOBBER );
160 
161 	DPRINTF("val = 0x" RFMT "\n", val);
162 
163 	if (toreg)
164 		regs->gr[toreg] = val;
165 
166 	return ret;
167 }
168 
169 static int emulate_ldw(struct pt_regs *regs, int toreg, int flop)
170 {
171 	unsigned long saddr = regs->ior;
172 	unsigned long val = 0;
173 	int ret;
174 
175 	DPRINTF("load " RFMT ":" RFMT " to r%d for 4 bytes\n",
176 		regs->isr, regs->ior, toreg);
177 
178 	__asm__ __volatile__  (
179 "	zdep	%3,28,2,%%r19\n"		/* r19=(ofs&3)*8 */
180 "	mtsp	%4, %%sr1\n"
181 "	depw	%%r0,31,2,%3\n"
182 "1:	ldw	0(%%sr1,%3),%0\n"
183 "2:	ldw	4(%%sr1,%3),%%r20\n"
184 "	subi	32,%%r19,%%r19\n"
185 "	mtctl	%%r19,11\n"
186 "	vshd	%0,%%r20,%0\n"
187 "	copy	%%r0, %1\n"
188 "3:	\n"
189 "	.section .fixup,\"ax\"\n"
190 "4:	ldi	-2, %1\n"
191 	FIXUP_BRANCH(3b)
192 "	.previous\n"
193 	ASM_EXCEPTIONTABLE_ENTRY(1b, 4b)
194 	ASM_EXCEPTIONTABLE_ENTRY(2b, 4b)
195 	: "=r" (val), "=r" (ret)
196 	: "0" (val), "r" (saddr), "r" (regs->isr)
197 	: "r19", "r20", FIXUP_BRANCH_CLOBBER );
198 
199 	DPRINTF("val = 0x" RFMT "\n", val);
200 
201 	if (flop)
202 		((__u32*)(regs->fr))[toreg] = val;
203 	else if (toreg)
204 		regs->gr[toreg] = val;
205 
206 	return ret;
207 }
208 static int emulate_ldd(struct pt_regs *regs, int toreg, int flop)
209 {
210 	unsigned long saddr = regs->ior;
211 	__u64 val = 0;
212 	int ret;
213 
214 	DPRINTF("load " RFMT ":" RFMT " to r%d for 8 bytes\n",
215 		regs->isr, regs->ior, toreg);
216 #ifdef CONFIG_PA20
217 
218 #ifndef CONFIG_64BIT
219 	if (!flop)
220 		return -1;
221 #endif
222 	__asm__ __volatile__  (
223 "	depd,z	%3,60,3,%%r19\n"		/* r19=(ofs&7)*8 */
224 "	mtsp	%4, %%sr1\n"
225 "	depd	%%r0,63,3,%3\n"
226 "1:	ldd	0(%%sr1,%3),%0\n"
227 "2:	ldd	8(%%sr1,%3),%%r20\n"
228 "	subi	64,%%r19,%%r19\n"
229 "	mtsar	%%r19\n"
230 "	shrpd	%0,%%r20,%%sar,%0\n"
231 "	copy	%%r0, %1\n"
232 "3:	\n"
233 "	.section .fixup,\"ax\"\n"
234 "4:	ldi	-2, %1\n"
235 	FIXUP_BRANCH(3b)
236 "	.previous\n"
237 	ASM_EXCEPTIONTABLE_ENTRY(1b,4b)
238 	ASM_EXCEPTIONTABLE_ENTRY(2b,4b)
239 	: "=r" (val), "=r" (ret)
240 	: "0" (val), "r" (saddr), "r" (regs->isr)
241 	: "r19", "r20", FIXUP_BRANCH_CLOBBER );
242 #else
243     {
244 	unsigned long valh=0,vall=0;
245 	__asm__ __volatile__  (
246 "	zdep	%5,29,2,%%r19\n"		/* r19=(ofs&3)*8 */
247 "	mtsp	%6, %%sr1\n"
248 "	dep	%%r0,31,2,%5\n"
249 "1:	ldw	0(%%sr1,%5),%0\n"
250 "2:	ldw	4(%%sr1,%5),%1\n"
251 "3:	ldw	8(%%sr1,%5),%%r20\n"
252 "	subi	32,%%r19,%%r19\n"
253 "	mtsar	%%r19\n"
254 "	vshd	%0,%1,%0\n"
255 "	vshd	%1,%%r20,%1\n"
256 "	copy	%%r0, %2\n"
257 "4:	\n"
258 "	.section .fixup,\"ax\"\n"
259 "5:	ldi	-2, %2\n"
260 	FIXUP_BRANCH(4b)
261 "	.previous\n"
262 	ASM_EXCEPTIONTABLE_ENTRY(1b,5b)
263 	ASM_EXCEPTIONTABLE_ENTRY(2b,5b)
264 	ASM_EXCEPTIONTABLE_ENTRY(3b,5b)
265 	: "=r" (valh), "=r" (vall), "=r" (ret)
266 	: "0" (valh), "1" (vall), "r" (saddr), "r" (regs->isr)
267 	: "r19", "r20", FIXUP_BRANCH_CLOBBER );
268 	val=((__u64)valh<<32)|(__u64)vall;
269     }
270 #endif
271 
272 	DPRINTF("val = 0x%llx\n", val);
273 
274 	if (flop)
275 		regs->fr[toreg] = val;
276 	else if (toreg)
277 		regs->gr[toreg] = val;
278 
279 	return ret;
280 }
281 
282 static int emulate_sth(struct pt_regs *regs, int frreg)
283 {
284 	unsigned long val = regs->gr[frreg];
285 	int ret;
286 
287 	if (!frreg)
288 		val = 0;
289 
290 	DPRINTF("store r%d (0x" RFMT ") to " RFMT ":" RFMT " for 2 bytes\n", frreg,
291 		val, regs->isr, regs->ior);
292 
293 	__asm__ __volatile__ (
294 "	mtsp %3, %%sr1\n"
295 "	extrw,u %1, 23, 8, %%r19\n"
296 "1:	stb %1, 1(%%sr1, %2)\n"
297 "2:	stb %%r19, 0(%%sr1, %2)\n"
298 "	copy	%%r0, %0\n"
299 "3:	\n"
300 "	.section .fixup,\"ax\"\n"
301 "4:	ldi	-2, %0\n"
302 	FIXUP_BRANCH(3b)
303 "	.previous\n"
304 	ASM_EXCEPTIONTABLE_ENTRY(1b,4b)
305 	ASM_EXCEPTIONTABLE_ENTRY(2b,4b)
306 	: "=r" (ret)
307 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
308 	: "r19", FIXUP_BRANCH_CLOBBER );
309 
310 	return ret;
311 }
312 
313 static int emulate_stw(struct pt_regs *regs, int frreg, int flop)
314 {
315 	unsigned long val;
316 	int ret;
317 
318 	if (flop)
319 		val = ((__u32*)(regs->fr))[frreg];
320 	else if (frreg)
321 		val = regs->gr[frreg];
322 	else
323 		val = 0;
324 
325 	DPRINTF("store r%d (0x" RFMT ") to " RFMT ":" RFMT " for 4 bytes\n", frreg,
326 		val, regs->isr, regs->ior);
327 
328 
329 	__asm__ __volatile__ (
330 "	mtsp %3, %%sr1\n"
331 "	zdep	%2, 28, 2, %%r19\n"
332 "	dep	%%r0, 31, 2, %2\n"
333 "	mtsar	%%r19\n"
334 "	depwi,z	-2, %%sar, 32, %%r19\n"
335 "1:	ldw	0(%%sr1,%2),%%r20\n"
336 "2:	ldw	4(%%sr1,%2),%%r21\n"
337 "	vshd	%%r0, %1, %%r22\n"
338 "	vshd	%1, %%r0, %%r1\n"
339 "	and	%%r20, %%r19, %%r20\n"
340 "	andcm	%%r21, %%r19, %%r21\n"
341 "	or	%%r22, %%r20, %%r20\n"
342 "	or	%%r1, %%r21, %%r21\n"
343 "	stw	%%r20,0(%%sr1,%2)\n"
344 "	stw	%%r21,4(%%sr1,%2)\n"
345 "	copy	%%r0, %0\n"
346 "3:	\n"
347 "	.section .fixup,\"ax\"\n"
348 "4:	ldi	-2, %0\n"
349 	FIXUP_BRANCH(3b)
350 "	.previous\n"
351 	ASM_EXCEPTIONTABLE_ENTRY(1b,4b)
352 	ASM_EXCEPTIONTABLE_ENTRY(2b,4b)
353 	: "=r" (ret)
354 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
355 	: "r19", "r20", "r21", "r22", "r1", FIXUP_BRANCH_CLOBBER );
356 
357 	return 0;
358 }
359 static int emulate_std(struct pt_regs *regs, int frreg, int flop)
360 {
361 	__u64 val;
362 	int ret;
363 
364 	if (flop)
365 		val = regs->fr[frreg];
366 	else if (frreg)
367 		val = regs->gr[frreg];
368 	else
369 		val = 0;
370 
371 	DPRINTF("store r%d (0x%016llx) to " RFMT ":" RFMT " for 8 bytes\n", frreg,
372 		val,  regs->isr, regs->ior);
373 
374 #ifdef CONFIG_PA20
375 #ifndef CONFIG_64BIT
376 	if (!flop)
377 		return -1;
378 #endif
379 	__asm__ __volatile__ (
380 "	mtsp %3, %%sr1\n"
381 "	depd,z	%2, 60, 3, %%r19\n"
382 "	depd	%%r0, 63, 3, %2\n"
383 "	mtsar	%%r19\n"
384 "	depdi,z	-2, %%sar, 64, %%r19\n"
385 "1:	ldd	0(%%sr1,%2),%%r20\n"
386 "2:	ldd	8(%%sr1,%2),%%r21\n"
387 "	shrpd	%%r0, %1, %%sar, %%r22\n"
388 "	shrpd	%1, %%r0, %%sar, %%r1\n"
389 "	and	%%r20, %%r19, %%r20\n"
390 "	andcm	%%r21, %%r19, %%r21\n"
391 "	or	%%r22, %%r20, %%r20\n"
392 "	or	%%r1, %%r21, %%r21\n"
393 "3:	std	%%r20,0(%%sr1,%2)\n"
394 "4:	std	%%r21,8(%%sr1,%2)\n"
395 "	copy	%%r0, %0\n"
396 "5:	\n"
397 "	.section .fixup,\"ax\"\n"
398 "6:	ldi	-2, %0\n"
399 	FIXUP_BRANCH(5b)
400 "	.previous\n"
401 	ASM_EXCEPTIONTABLE_ENTRY(1b,6b)
402 	ASM_EXCEPTIONTABLE_ENTRY(2b,6b)
403 	ASM_EXCEPTIONTABLE_ENTRY(3b,6b)
404 	ASM_EXCEPTIONTABLE_ENTRY(4b,6b)
405 	: "=r" (ret)
406 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
407 	: "r19", "r20", "r21", "r22", "r1", FIXUP_BRANCH_CLOBBER );
408 #else
409     {
410 	unsigned long valh=(val>>32),vall=(val&0xffffffffl);
411 	__asm__ __volatile__ (
412 "	mtsp	%4, %%sr1\n"
413 "	zdep	%2, 29, 2, %%r19\n"
414 "	dep	%%r0, 31, 2, %2\n"
415 "	mtsar	%%r19\n"
416 "	zvdepi	-2, 32, %%r19\n"
417 "1:	ldw	0(%%sr1,%3),%%r20\n"
418 "2:	ldw	8(%%sr1,%3),%%r21\n"
419 "	vshd	%1, %2, %%r1\n"
420 "	vshd	%%r0, %1, %1\n"
421 "	vshd	%2, %%r0, %2\n"
422 "	and	%%r20, %%r19, %%r20\n"
423 "	andcm	%%r21, %%r19, %%r21\n"
424 "	or	%1, %%r20, %1\n"
425 "	or	%2, %%r21, %2\n"
426 "3:	stw	%1,0(%%sr1,%1)\n"
427 "4:	stw	%%r1,4(%%sr1,%3)\n"
428 "5:	stw	%2,8(%%sr1,%3)\n"
429 "	copy	%%r0, %0\n"
430 "6:	\n"
431 "	.section .fixup,\"ax\"\n"
432 "7:	ldi	-2, %0\n"
433 	FIXUP_BRANCH(6b)
434 "	.previous\n"
435 	ASM_EXCEPTIONTABLE_ENTRY(1b,7b)
436 	ASM_EXCEPTIONTABLE_ENTRY(2b,7b)
437 	ASM_EXCEPTIONTABLE_ENTRY(3b,7b)
438 	ASM_EXCEPTIONTABLE_ENTRY(4b,7b)
439 	ASM_EXCEPTIONTABLE_ENTRY(5b,7b)
440 	: "=r" (ret)
441 	: "r" (valh), "r" (vall), "r" (regs->ior), "r" (regs->isr)
442 	: "r19", "r20", "r21", "r1", FIXUP_BRANCH_CLOBBER );
443     }
444 #endif
445 
446 	return ret;
447 }
448 
449 void handle_unaligned(struct pt_regs *regs)
450 {
451 	static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
452 	unsigned long newbase = R1(regs->iir)?regs->gr[R1(regs->iir)]:0;
453 	int modify = 0;
454 	int ret = ERR_NOTHANDLED;
455 	register int flop=0;	/* true if this is a flop */
456 
457 	__inc_irq_stat(irq_unaligned_count);
458 
459 	/* log a message with pacing */
460 	if (user_mode(regs)) {
461 		if (current->thread.flags & PARISC_UAC_SIGBUS) {
462 			goto force_sigbus;
463 		}
464 
465 		if (!(current->thread.flags & PARISC_UAC_NOPRINT) &&
466 			__ratelimit(&ratelimit)) {
467 			char buf[256];
468 			sprintf(buf, "%s(%d): unaligned access to 0x" RFMT " at ip=0x" RFMT "\n",
469 				current->comm, task_pid_nr(current), regs->ior, regs->iaoq[0]);
470 			printk(KERN_WARNING "%s", buf);
471 #ifdef DEBUG_UNALIGNED
472 			show_regs(regs);
473 #endif
474 		}
475 
476 		if (!unaligned_enabled)
477 			goto force_sigbus;
478 	}
479 
480 	/* handle modification - OK, it's ugly, see the instruction manual */
481 	switch (MAJOR_OP(regs->iir))
482 	{
483 	case 0x03:
484 	case 0x09:
485 	case 0x0b:
486 		if (regs->iir&0x20)
487 		{
488 			modify = 1;
489 			if (regs->iir&0x1000)		/* short loads */
490 				if (regs->iir&0x200)
491 					newbase += IM5_3(regs->iir);
492 				else
493 					newbase += IM5_2(regs->iir);
494 			else if (regs->iir&0x2000)	/* scaled indexed */
495 			{
496 				int shift=0;
497 				switch (regs->iir & OPCODE1_MASK)
498 				{
499 				case OPCODE_LDH_I:
500 					shift= 1; break;
501 				case OPCODE_LDW_I:
502 					shift= 2; break;
503 				case OPCODE_LDD_I:
504 				case OPCODE_LDDA_I:
505 					shift= 3; break;
506 				}
507 				newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0)<<shift;
508 			} else				/* simple indexed */
509 				newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0);
510 		}
511 		break;
512 	case 0x13:
513 	case 0x1b:
514 		modify = 1;
515 		newbase += IM14(regs->iir);
516 		break;
517 	case 0x14:
518 	case 0x1c:
519 		if (regs->iir&8)
520 		{
521 			modify = 1;
522 			newbase += IM14(regs->iir&~0xe);
523 		}
524 		break;
525 	case 0x16:
526 	case 0x1e:
527 		modify = 1;
528 		newbase += IM14(regs->iir&6);
529 		break;
530 	case 0x17:
531 	case 0x1f:
532 		if (regs->iir&4)
533 		{
534 			modify = 1;
535 			newbase += IM14(regs->iir&~4);
536 		}
537 		break;
538 	}
539 
540 	/* TODO: make this cleaner... */
541 	switch (regs->iir & OPCODE1_MASK)
542 	{
543 	case OPCODE_LDH_I:
544 	case OPCODE_LDH_S:
545 		ret = emulate_ldh(regs, R3(regs->iir));
546 		break;
547 
548 	case OPCODE_LDW_I:
549 	case OPCODE_LDWA_I:
550 	case OPCODE_LDW_S:
551 	case OPCODE_LDWA_S:
552 		ret = emulate_ldw(regs, R3(regs->iir),0);
553 		break;
554 
555 	case OPCODE_STH:
556 		ret = emulate_sth(regs, R2(regs->iir));
557 		break;
558 
559 	case OPCODE_STW:
560 	case OPCODE_STWA:
561 		ret = emulate_stw(regs, R2(regs->iir),0);
562 		break;
563 
564 #ifdef CONFIG_PA20
565 	case OPCODE_LDD_I:
566 	case OPCODE_LDDA_I:
567 	case OPCODE_LDD_S:
568 	case OPCODE_LDDA_S:
569 		ret = emulate_ldd(regs, R3(regs->iir),0);
570 		break;
571 
572 	case OPCODE_STD:
573 	case OPCODE_STDA:
574 		ret = emulate_std(regs, R2(regs->iir),0);
575 		break;
576 #endif
577 
578 	case OPCODE_FLDWX:
579 	case OPCODE_FLDWS:
580 	case OPCODE_FLDWXR:
581 	case OPCODE_FLDWSR:
582 		flop=1;
583 		ret = emulate_ldw(regs,FR3(regs->iir),1);
584 		break;
585 
586 	case OPCODE_FLDDX:
587 	case OPCODE_FLDDS:
588 		flop=1;
589 		ret = emulate_ldd(regs,R3(regs->iir),1);
590 		break;
591 
592 	case OPCODE_FSTWX:
593 	case OPCODE_FSTWS:
594 	case OPCODE_FSTWXR:
595 	case OPCODE_FSTWSR:
596 		flop=1;
597 		ret = emulate_stw(regs,FR3(regs->iir),1);
598 		break;
599 
600 	case OPCODE_FSTDX:
601 	case OPCODE_FSTDS:
602 		flop=1;
603 		ret = emulate_std(regs,R3(regs->iir),1);
604 		break;
605 
606 	case OPCODE_LDCD_I:
607 	case OPCODE_LDCW_I:
608 	case OPCODE_LDCD_S:
609 	case OPCODE_LDCW_S:
610 		ret = ERR_NOTHANDLED;	/* "undefined", but lets kill them. */
611 		break;
612 	}
613 #ifdef CONFIG_PA20
614 	switch (regs->iir & OPCODE2_MASK)
615 	{
616 	case OPCODE_FLDD_L:
617 		flop=1;
618 		ret = emulate_ldd(regs,R2(regs->iir),1);
619 		break;
620 	case OPCODE_FSTD_L:
621 		flop=1;
622 		ret = emulate_std(regs, R2(regs->iir),1);
623 		break;
624 	case OPCODE_LDD_L:
625 		ret = emulate_ldd(regs, R2(regs->iir),0);
626 		break;
627 	case OPCODE_STD_L:
628 		ret = emulate_std(regs, R2(regs->iir),0);
629 		break;
630 	}
631 #endif
632 	switch (regs->iir & OPCODE3_MASK)
633 	{
634 	case OPCODE_FLDW_L:
635 		flop=1;
636 		ret = emulate_ldw(regs, R2(regs->iir),0);
637 		break;
638 	case OPCODE_LDW_M:
639 		ret = emulate_ldw(regs, R2(regs->iir),1);
640 		break;
641 
642 	case OPCODE_FSTW_L:
643 		flop=1;
644 		ret = emulate_stw(regs, R2(regs->iir),1);
645 		break;
646 	case OPCODE_STW_M:
647 		ret = emulate_stw(regs, R2(regs->iir),0);
648 		break;
649 	}
650 	switch (regs->iir & OPCODE4_MASK)
651 	{
652 	case OPCODE_LDH_L:
653 		ret = emulate_ldh(regs, R2(regs->iir));
654 		break;
655 	case OPCODE_LDW_L:
656 	case OPCODE_LDWM:
657 		ret = emulate_ldw(regs, R2(regs->iir),0);
658 		break;
659 	case OPCODE_STH_L:
660 		ret = emulate_sth(regs, R2(regs->iir));
661 		break;
662 	case OPCODE_STW_L:
663 	case OPCODE_STWM:
664 		ret = emulate_stw(regs, R2(regs->iir),0);
665 		break;
666 	}
667 
668 	if (ret == 0 && modify && R1(regs->iir))
669 		regs->gr[R1(regs->iir)] = newbase;
670 
671 
672 	if (ret == ERR_NOTHANDLED)
673 		printk(KERN_CRIT "Not-handled unaligned insn 0x%08lx\n", regs->iir);
674 
675 	DPRINTF("ret = %d\n", ret);
676 
677 	if (ret)
678 	{
679 		/*
680 		 * The unaligned handler failed.
681 		 * If we were called by __get_user() or __put_user() jump
682 		 * to it's exception fixup handler instead of crashing.
683 		 */
684 		if (!user_mode(regs) && fixup_exception(regs))
685 			return;
686 
687 		printk(KERN_CRIT "Unaligned handler failed, ret = %d\n", ret);
688 		die_if_kernel("Unaligned data reference", regs, 28);
689 
690 		if (ret == ERR_PAGEFAULT)
691 		{
692 			force_sig_fault(SIGSEGV, SEGV_MAPERR,
693 					(void __user *)regs->ior, current);
694 		}
695 		else
696 		{
697 force_sigbus:
698 			/* couldn't handle it ... */
699 			force_sig_fault(SIGBUS, BUS_ADRALN,
700 					(void __user *)regs->ior, current);
701 		}
702 
703 		return;
704 	}
705 
706 	/* else we handled it, let life go on. */
707 	regs->gr[0]|=PSW_N;
708 }
709 
710 /*
711  * NB: check_unaligned() is only used for PCXS processors right
712  * now, so we only check for PA1.1 encodings at this point.
713  */
714 
715 int
716 check_unaligned(struct pt_regs *regs)
717 {
718 	unsigned long align_mask;
719 
720 	/* Get alignment mask */
721 
722 	align_mask = 0UL;
723 	switch (regs->iir & OPCODE1_MASK) {
724 
725 	case OPCODE_LDH_I:
726 	case OPCODE_LDH_S:
727 	case OPCODE_STH:
728 		align_mask = 1UL;
729 		break;
730 
731 	case OPCODE_LDW_I:
732 	case OPCODE_LDWA_I:
733 	case OPCODE_LDW_S:
734 	case OPCODE_LDWA_S:
735 	case OPCODE_STW:
736 	case OPCODE_STWA:
737 		align_mask = 3UL;
738 		break;
739 
740 	default:
741 		switch (regs->iir & OPCODE4_MASK) {
742 		case OPCODE_LDH_L:
743 		case OPCODE_STH_L:
744 			align_mask = 1UL;
745 			break;
746 		case OPCODE_LDW_L:
747 		case OPCODE_LDWM:
748 		case OPCODE_STW_L:
749 		case OPCODE_STWM:
750 			align_mask = 3UL;
751 			break;
752 		}
753 		break;
754 	}
755 
756 	return (int)(regs->ior & align_mask);
757 }
758 
759