xref: /openbmc/linux/arch/parisc/kernel/unaligned.c (revision dd21bfa4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *    Unaligned memory access handler
4  *
5  *    Copyright (C) 2001 Randolph Chung <tausq@debian.org>
6  *    Significantly tweaked by LaMont Jones <lamont@debian.org>
7  */
8 
9 #include <linux/jiffies.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/sched/signal.h>
13 #include <linux/sched/debug.h>
14 #include <linux/signal.h>
15 #include <linux/ratelimit.h>
16 #include <linux/uaccess.h>
17 #include <asm/hardirq.h>
18 #include <asm/traps.h>
19 
20 /* #define DEBUG_UNALIGNED 1 */
21 
22 #ifdef DEBUG_UNALIGNED
23 #define DPRINTF(fmt, args...) do { printk(KERN_DEBUG "%s:%d:%s ", __FILE__, __LINE__, __func__ ); printk(KERN_DEBUG fmt, ##args ); } while (0)
24 #else
25 #define DPRINTF(fmt, args...)
26 #endif
27 
28 #ifdef CONFIG_64BIT
29 #define RFMT "%016lx"
30 #else
31 #define RFMT "%08lx"
32 #endif
33 
34 #define FIXUP_BRANCH(lbl) \
35 	"\tldil L%%" #lbl ", %%r1\n"			\
36 	"\tldo R%%" #lbl "(%%r1), %%r1\n"		\
37 	"\tbv,n %%r0(%%r1)\n"
38 /* If you use FIXUP_BRANCH, then you must list this clobber */
39 #define FIXUP_BRANCH_CLOBBER "r1"
40 
41 /* 1111 1100 0000 0000 0001 0011 1100 0000 */
42 #define OPCODE1(a,b,c)	((a)<<26|(b)<<12|(c)<<6)
43 #define OPCODE2(a,b)	((a)<<26|(b)<<1)
44 #define OPCODE3(a,b)	((a)<<26|(b)<<2)
45 #define OPCODE4(a)	((a)<<26)
46 #define OPCODE1_MASK	OPCODE1(0x3f,1,0xf)
47 #define OPCODE2_MASK 	OPCODE2(0x3f,1)
48 #define OPCODE3_MASK	OPCODE3(0x3f,1)
49 #define OPCODE4_MASK    OPCODE4(0x3f)
50 
51 /* skip LDB - never unaligned (index) */
52 #define OPCODE_LDH_I	OPCODE1(0x03,0,0x1)
53 #define OPCODE_LDW_I	OPCODE1(0x03,0,0x2)
54 #define OPCODE_LDD_I	OPCODE1(0x03,0,0x3)
55 #define OPCODE_LDDA_I	OPCODE1(0x03,0,0x4)
56 #define OPCODE_LDCD_I	OPCODE1(0x03,0,0x5)
57 #define OPCODE_LDWA_I	OPCODE1(0x03,0,0x6)
58 #define OPCODE_LDCW_I	OPCODE1(0x03,0,0x7)
59 /* skip LDB - never unaligned (short) */
60 #define OPCODE_LDH_S	OPCODE1(0x03,1,0x1)
61 #define OPCODE_LDW_S	OPCODE1(0x03,1,0x2)
62 #define OPCODE_LDD_S	OPCODE1(0x03,1,0x3)
63 #define OPCODE_LDDA_S	OPCODE1(0x03,1,0x4)
64 #define OPCODE_LDCD_S	OPCODE1(0x03,1,0x5)
65 #define OPCODE_LDWA_S	OPCODE1(0x03,1,0x6)
66 #define OPCODE_LDCW_S	OPCODE1(0x03,1,0x7)
67 /* skip STB - never unaligned */
68 #define OPCODE_STH	OPCODE1(0x03,1,0x9)
69 #define OPCODE_STW	OPCODE1(0x03,1,0xa)
70 #define OPCODE_STD	OPCODE1(0x03,1,0xb)
71 /* skip STBY - never unaligned */
72 /* skip STDBY - never unaligned */
73 #define OPCODE_STWA	OPCODE1(0x03,1,0xe)
74 #define OPCODE_STDA	OPCODE1(0x03,1,0xf)
75 
76 #define OPCODE_FLDWX	OPCODE1(0x09,0,0x0)
77 #define OPCODE_FLDWXR	OPCODE1(0x09,0,0x1)
78 #define OPCODE_FSTWX	OPCODE1(0x09,0,0x8)
79 #define OPCODE_FSTWXR	OPCODE1(0x09,0,0x9)
80 #define OPCODE_FLDWS	OPCODE1(0x09,1,0x0)
81 #define OPCODE_FLDWSR	OPCODE1(0x09,1,0x1)
82 #define OPCODE_FSTWS	OPCODE1(0x09,1,0x8)
83 #define OPCODE_FSTWSR	OPCODE1(0x09,1,0x9)
84 #define OPCODE_FLDDX	OPCODE1(0x0b,0,0x0)
85 #define OPCODE_FSTDX	OPCODE1(0x0b,0,0x8)
86 #define OPCODE_FLDDS	OPCODE1(0x0b,1,0x0)
87 #define OPCODE_FSTDS	OPCODE1(0x0b,1,0x8)
88 
89 #define OPCODE_LDD_L	OPCODE2(0x14,0)
90 #define OPCODE_FLDD_L	OPCODE2(0x14,1)
91 #define OPCODE_STD_L	OPCODE2(0x1c,0)
92 #define OPCODE_FSTD_L	OPCODE2(0x1c,1)
93 
94 #define OPCODE_LDW_M	OPCODE3(0x17,1)
95 #define OPCODE_FLDW_L	OPCODE3(0x17,0)
96 #define OPCODE_FSTW_L	OPCODE3(0x1f,0)
97 #define OPCODE_STW_M	OPCODE3(0x1f,1)
98 
99 #define OPCODE_LDH_L    OPCODE4(0x11)
100 #define OPCODE_LDW_L    OPCODE4(0x12)
101 #define OPCODE_LDWM     OPCODE4(0x13)
102 #define OPCODE_STH_L    OPCODE4(0x19)
103 #define OPCODE_STW_L    OPCODE4(0x1A)
104 #define OPCODE_STWM     OPCODE4(0x1B)
105 
106 #define MAJOR_OP(i) (((i)>>26)&0x3f)
107 #define R1(i) (((i)>>21)&0x1f)
108 #define R2(i) (((i)>>16)&0x1f)
109 #define R3(i) ((i)&0x1f)
110 #define FR3(i) ((((i)<<1)&0x1f)|(((i)>>6)&1))
111 #define IM(i,n) (((i)>>1&((1<<(n-1))-1))|((i)&1?((0-1L)<<(n-1)):0))
112 #define IM5_2(i) IM((i)>>16,5)
113 #define IM5_3(i) IM((i),5)
114 #define IM14(i) IM((i),14)
115 
116 #define ERR_NOTHANDLED	-1
117 #define ERR_PAGEFAULT	-2
118 
119 int unaligned_enabled __read_mostly = 1;
120 
121 static int emulate_ldh(struct pt_regs *regs, int toreg)
122 {
123 	unsigned long saddr = regs->ior;
124 	unsigned long val = 0;
125 	int ret;
126 
127 	DPRINTF("load " RFMT ":" RFMT " to r%d for 2 bytes\n",
128 		regs->isr, regs->ior, toreg);
129 
130 	__asm__ __volatile__  (
131 "	mtsp	%4, %%sr1\n"
132 "1:	ldbs	0(%%sr1,%3), %%r20\n"
133 "2:	ldbs	1(%%sr1,%3), %0\n"
134 "	depw	%%r20, 23, 24, %0\n"
135 "	copy	%%r0, %1\n"
136 "3:	\n"
137 "	.section .fixup,\"ax\"\n"
138 "4:	ldi	-2, %1\n"
139 	FIXUP_BRANCH(3b)
140 "	.previous\n"
141 	ASM_EXCEPTIONTABLE_ENTRY(1b, 4b)
142 	ASM_EXCEPTIONTABLE_ENTRY(2b, 4b)
143 	: "=r" (val), "=r" (ret)
144 	: "0" (val), "r" (saddr), "r" (regs->isr)
145 	: "r20", FIXUP_BRANCH_CLOBBER );
146 
147 	DPRINTF("val = 0x" RFMT "\n", val);
148 
149 	if (toreg)
150 		regs->gr[toreg] = val;
151 
152 	return ret;
153 }
154 
155 static int emulate_ldw(struct pt_regs *regs, int toreg, int flop)
156 {
157 	unsigned long saddr = regs->ior;
158 	unsigned long val = 0;
159 	int ret;
160 
161 	DPRINTF("load " RFMT ":" RFMT " to r%d for 4 bytes\n",
162 		regs->isr, regs->ior, toreg);
163 
164 	__asm__ __volatile__  (
165 "	zdep	%3,28,2,%%r19\n"		/* r19=(ofs&3)*8 */
166 "	mtsp	%4, %%sr1\n"
167 "	depw	%%r0,31,2,%3\n"
168 "1:	ldw	0(%%sr1,%3),%0\n"
169 "2:	ldw	4(%%sr1,%3),%%r20\n"
170 "	subi	32,%%r19,%%r19\n"
171 "	mtctl	%%r19,11\n"
172 "	vshd	%0,%%r20,%0\n"
173 "	copy	%%r0, %1\n"
174 "3:	\n"
175 "	.section .fixup,\"ax\"\n"
176 "4:	ldi	-2, %1\n"
177 	FIXUP_BRANCH(3b)
178 "	.previous\n"
179 	ASM_EXCEPTIONTABLE_ENTRY(1b, 4b)
180 	ASM_EXCEPTIONTABLE_ENTRY(2b, 4b)
181 	: "=r" (val), "=r" (ret)
182 	: "0" (val), "r" (saddr), "r" (regs->isr)
183 	: "r19", "r20", FIXUP_BRANCH_CLOBBER );
184 
185 	DPRINTF("val = 0x" RFMT "\n", val);
186 
187 	if (flop)
188 		((__u32*)(regs->fr))[toreg] = val;
189 	else if (toreg)
190 		regs->gr[toreg] = val;
191 
192 	return ret;
193 }
194 static int emulate_ldd(struct pt_regs *regs, int toreg, int flop)
195 {
196 	unsigned long saddr = regs->ior;
197 	__u64 val = 0;
198 	int ret;
199 
200 	DPRINTF("load " RFMT ":" RFMT " to r%d for 8 bytes\n",
201 		regs->isr, regs->ior, toreg);
202 #ifdef CONFIG_PA20
203 
204 #ifndef CONFIG_64BIT
205 	if (!flop)
206 		return -1;
207 #endif
208 	__asm__ __volatile__  (
209 "	depd,z	%3,60,3,%%r19\n"		/* r19=(ofs&7)*8 */
210 "	mtsp	%4, %%sr1\n"
211 "	depd	%%r0,63,3,%3\n"
212 "1:	ldd	0(%%sr1,%3),%0\n"
213 "2:	ldd	8(%%sr1,%3),%%r20\n"
214 "	subi	64,%%r19,%%r19\n"
215 "	mtsar	%%r19\n"
216 "	shrpd	%0,%%r20,%%sar,%0\n"
217 "	copy	%%r0, %1\n"
218 "3:	\n"
219 "	.section .fixup,\"ax\"\n"
220 "4:	ldi	-2, %1\n"
221 	FIXUP_BRANCH(3b)
222 "	.previous\n"
223 	ASM_EXCEPTIONTABLE_ENTRY(1b,4b)
224 	ASM_EXCEPTIONTABLE_ENTRY(2b,4b)
225 	: "=r" (val), "=r" (ret)
226 	: "0" (val), "r" (saddr), "r" (regs->isr)
227 	: "r19", "r20", FIXUP_BRANCH_CLOBBER );
228 #else
229     {
230 	unsigned long valh=0,vall=0;
231 	__asm__ __volatile__  (
232 "	zdep	%5,29,2,%%r19\n"		/* r19=(ofs&3)*8 */
233 "	mtsp	%6, %%sr1\n"
234 "	dep	%%r0,31,2,%5\n"
235 "1:	ldw	0(%%sr1,%5),%0\n"
236 "2:	ldw	4(%%sr1,%5),%1\n"
237 "3:	ldw	8(%%sr1,%5),%%r20\n"
238 "	subi	32,%%r19,%%r19\n"
239 "	mtsar	%%r19\n"
240 "	vshd	%0,%1,%0\n"
241 "	vshd	%1,%%r20,%1\n"
242 "	copy	%%r0, %2\n"
243 "4:	\n"
244 "	.section .fixup,\"ax\"\n"
245 "5:	ldi	-2, %2\n"
246 	FIXUP_BRANCH(4b)
247 "	.previous\n"
248 	ASM_EXCEPTIONTABLE_ENTRY(1b,5b)
249 	ASM_EXCEPTIONTABLE_ENTRY(2b,5b)
250 	ASM_EXCEPTIONTABLE_ENTRY(3b,5b)
251 	: "=r" (valh), "=r" (vall), "=r" (ret)
252 	: "0" (valh), "1" (vall), "r" (saddr), "r" (regs->isr)
253 	: "r19", "r20", FIXUP_BRANCH_CLOBBER );
254 	val=((__u64)valh<<32)|(__u64)vall;
255     }
256 #endif
257 
258 	DPRINTF("val = 0x%llx\n", val);
259 
260 	if (flop)
261 		regs->fr[toreg] = val;
262 	else if (toreg)
263 		regs->gr[toreg] = val;
264 
265 	return ret;
266 }
267 
268 static int emulate_sth(struct pt_regs *regs, int frreg)
269 {
270 	unsigned long val = regs->gr[frreg];
271 	int ret;
272 
273 	if (!frreg)
274 		val = 0;
275 
276 	DPRINTF("store r%d (0x" RFMT ") to " RFMT ":" RFMT " for 2 bytes\n", frreg,
277 		val, regs->isr, regs->ior);
278 
279 	__asm__ __volatile__ (
280 "	mtsp %3, %%sr1\n"
281 "	extrw,u %1, 23, 8, %%r19\n"
282 "1:	stb %1, 1(%%sr1, %2)\n"
283 "2:	stb %%r19, 0(%%sr1, %2)\n"
284 "	copy	%%r0, %0\n"
285 "3:	\n"
286 "	.section .fixup,\"ax\"\n"
287 "4:	ldi	-2, %0\n"
288 	FIXUP_BRANCH(3b)
289 "	.previous\n"
290 	ASM_EXCEPTIONTABLE_ENTRY(1b,4b)
291 	ASM_EXCEPTIONTABLE_ENTRY(2b,4b)
292 	: "=r" (ret)
293 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
294 	: "r19", FIXUP_BRANCH_CLOBBER );
295 
296 	return ret;
297 }
298 
299 static int emulate_stw(struct pt_regs *regs, int frreg, int flop)
300 {
301 	unsigned long val;
302 	int ret;
303 
304 	if (flop)
305 		val = ((__u32*)(regs->fr))[frreg];
306 	else if (frreg)
307 		val = regs->gr[frreg];
308 	else
309 		val = 0;
310 
311 	DPRINTF("store r%d (0x" RFMT ") to " RFMT ":" RFMT " for 4 bytes\n", frreg,
312 		val, regs->isr, regs->ior);
313 
314 
315 	__asm__ __volatile__ (
316 "	mtsp %3, %%sr1\n"
317 "	zdep	%2, 28, 2, %%r19\n"
318 "	dep	%%r0, 31, 2, %2\n"
319 "	mtsar	%%r19\n"
320 "	depwi,z	-2, %%sar, 32, %%r19\n"
321 "1:	ldw	0(%%sr1,%2),%%r20\n"
322 "2:	ldw	4(%%sr1,%2),%%r21\n"
323 "	vshd	%%r0, %1, %%r22\n"
324 "	vshd	%1, %%r0, %%r1\n"
325 "	and	%%r20, %%r19, %%r20\n"
326 "	andcm	%%r21, %%r19, %%r21\n"
327 "	or	%%r22, %%r20, %%r20\n"
328 "	or	%%r1, %%r21, %%r21\n"
329 "	stw	%%r20,0(%%sr1,%2)\n"
330 "	stw	%%r21,4(%%sr1,%2)\n"
331 "	copy	%%r0, %0\n"
332 "3:	\n"
333 "	.section .fixup,\"ax\"\n"
334 "4:	ldi	-2, %0\n"
335 	FIXUP_BRANCH(3b)
336 "	.previous\n"
337 	ASM_EXCEPTIONTABLE_ENTRY(1b,4b)
338 	ASM_EXCEPTIONTABLE_ENTRY(2b,4b)
339 	: "=r" (ret)
340 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
341 	: "r19", "r20", "r21", "r22", "r1", FIXUP_BRANCH_CLOBBER );
342 
343 	return ret;
344 }
345 static int emulate_std(struct pt_regs *regs, int frreg, int flop)
346 {
347 	__u64 val;
348 	int ret;
349 
350 	if (flop)
351 		val = regs->fr[frreg];
352 	else if (frreg)
353 		val = regs->gr[frreg];
354 	else
355 		val = 0;
356 
357 	DPRINTF("store r%d (0x%016llx) to " RFMT ":" RFMT " for 8 bytes\n", frreg,
358 		val,  regs->isr, regs->ior);
359 
360 #ifdef CONFIG_PA20
361 #ifndef CONFIG_64BIT
362 	if (!flop)
363 		return -1;
364 #endif
365 	__asm__ __volatile__ (
366 "	mtsp %3, %%sr1\n"
367 "	depd,z	%2, 60, 3, %%r19\n"
368 "	depd	%%r0, 63, 3, %2\n"
369 "	mtsar	%%r19\n"
370 "	depdi,z	-2, %%sar, 64, %%r19\n"
371 "1:	ldd	0(%%sr1,%2),%%r20\n"
372 "2:	ldd	8(%%sr1,%2),%%r21\n"
373 "	shrpd	%%r0, %1, %%sar, %%r22\n"
374 "	shrpd	%1, %%r0, %%sar, %%r1\n"
375 "	and	%%r20, %%r19, %%r20\n"
376 "	andcm	%%r21, %%r19, %%r21\n"
377 "	or	%%r22, %%r20, %%r20\n"
378 "	or	%%r1, %%r21, %%r21\n"
379 "3:	std	%%r20,0(%%sr1,%2)\n"
380 "4:	std	%%r21,8(%%sr1,%2)\n"
381 "	copy	%%r0, %0\n"
382 "5:	\n"
383 "	.section .fixup,\"ax\"\n"
384 "6:	ldi	-2, %0\n"
385 	FIXUP_BRANCH(5b)
386 "	.previous\n"
387 	ASM_EXCEPTIONTABLE_ENTRY(1b,6b)
388 	ASM_EXCEPTIONTABLE_ENTRY(2b,6b)
389 	ASM_EXCEPTIONTABLE_ENTRY(3b,6b)
390 	ASM_EXCEPTIONTABLE_ENTRY(4b,6b)
391 	: "=r" (ret)
392 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
393 	: "r19", "r20", "r21", "r22", "r1", FIXUP_BRANCH_CLOBBER );
394 #else
395     {
396 	unsigned long valh=(val>>32),vall=(val&0xffffffffl);
397 	__asm__ __volatile__ (
398 "	mtsp	%4, %%sr1\n"
399 "	zdep	%2, 29, 2, %%r19\n"
400 "	dep	%%r0, 31, 2, %3\n"
401 "	mtsar	%%r19\n"
402 "	zvdepi	-2, 32, %%r19\n"
403 "1:	ldw	0(%%sr1,%3),%%r20\n"
404 "2:	ldw	8(%%sr1,%3),%%r21\n"
405 "	vshd	%1, %2, %%r1\n"
406 "	vshd	%%r0, %1, %1\n"
407 "	vshd	%2, %%r0, %2\n"
408 "	and	%%r20, %%r19, %%r20\n"
409 "	andcm	%%r21, %%r19, %%r21\n"
410 "	or	%1, %%r20, %1\n"
411 "	or	%2, %%r21, %2\n"
412 "3:	stw	%1,0(%%sr1,%3)\n"
413 "4:	stw	%%r1,4(%%sr1,%3)\n"
414 "5:	stw	%2,8(%%sr1,%3)\n"
415 "	copy	%%r0, %0\n"
416 "6:	\n"
417 "	.section .fixup,\"ax\"\n"
418 "7:	ldi	-2, %0\n"
419 	FIXUP_BRANCH(6b)
420 "	.previous\n"
421 	ASM_EXCEPTIONTABLE_ENTRY(1b,7b)
422 	ASM_EXCEPTIONTABLE_ENTRY(2b,7b)
423 	ASM_EXCEPTIONTABLE_ENTRY(3b,7b)
424 	ASM_EXCEPTIONTABLE_ENTRY(4b,7b)
425 	ASM_EXCEPTIONTABLE_ENTRY(5b,7b)
426 	: "=r" (ret)
427 	: "r" (valh), "r" (vall), "r" (regs->ior), "r" (regs->isr)
428 	: "r19", "r20", "r21", "r1", FIXUP_BRANCH_CLOBBER );
429     }
430 #endif
431 
432 	return ret;
433 }
434 
435 void handle_unaligned(struct pt_regs *regs)
436 {
437 	static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
438 	unsigned long newbase = R1(regs->iir)?regs->gr[R1(regs->iir)]:0;
439 	int modify = 0;
440 	int ret = ERR_NOTHANDLED;
441 	register int flop=0;	/* true if this is a flop */
442 
443 	__inc_irq_stat(irq_unaligned_count);
444 
445 	/* log a message with pacing */
446 	if (user_mode(regs)) {
447 		if (current->thread.flags & PARISC_UAC_SIGBUS) {
448 			goto force_sigbus;
449 		}
450 
451 		if (!(current->thread.flags & PARISC_UAC_NOPRINT) &&
452 			__ratelimit(&ratelimit)) {
453 			char buf[256];
454 			sprintf(buf, "%s(%d): unaligned access to 0x" RFMT " at ip=0x" RFMT "\n",
455 				current->comm, task_pid_nr(current), regs->ior, regs->iaoq[0]);
456 			printk(KERN_WARNING "%s", buf);
457 #ifdef DEBUG_UNALIGNED
458 			show_regs(regs);
459 #endif
460 		}
461 
462 		if (!unaligned_enabled)
463 			goto force_sigbus;
464 	}
465 
466 	/* handle modification - OK, it's ugly, see the instruction manual */
467 	switch (MAJOR_OP(regs->iir))
468 	{
469 	case 0x03:
470 	case 0x09:
471 	case 0x0b:
472 		if (regs->iir&0x20)
473 		{
474 			modify = 1;
475 			if (regs->iir&0x1000)		/* short loads */
476 				if (regs->iir&0x200)
477 					newbase += IM5_3(regs->iir);
478 				else
479 					newbase += IM5_2(regs->iir);
480 			else if (regs->iir&0x2000)	/* scaled indexed */
481 			{
482 				int shift=0;
483 				switch (regs->iir & OPCODE1_MASK)
484 				{
485 				case OPCODE_LDH_I:
486 					shift= 1; break;
487 				case OPCODE_LDW_I:
488 					shift= 2; break;
489 				case OPCODE_LDD_I:
490 				case OPCODE_LDDA_I:
491 					shift= 3; break;
492 				}
493 				newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0)<<shift;
494 			} else				/* simple indexed */
495 				newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0);
496 		}
497 		break;
498 	case 0x13:
499 	case 0x1b:
500 		modify = 1;
501 		newbase += IM14(regs->iir);
502 		break;
503 	case 0x14:
504 	case 0x1c:
505 		if (regs->iir&8)
506 		{
507 			modify = 1;
508 			newbase += IM14(regs->iir&~0xe);
509 		}
510 		break;
511 	case 0x16:
512 	case 0x1e:
513 		modify = 1;
514 		newbase += IM14(regs->iir&6);
515 		break;
516 	case 0x17:
517 	case 0x1f:
518 		if (regs->iir&4)
519 		{
520 			modify = 1;
521 			newbase += IM14(regs->iir&~4);
522 		}
523 		break;
524 	}
525 
526 	/* TODO: make this cleaner... */
527 	switch (regs->iir & OPCODE1_MASK)
528 	{
529 	case OPCODE_LDH_I:
530 	case OPCODE_LDH_S:
531 		ret = emulate_ldh(regs, R3(regs->iir));
532 		break;
533 
534 	case OPCODE_LDW_I:
535 	case OPCODE_LDWA_I:
536 	case OPCODE_LDW_S:
537 	case OPCODE_LDWA_S:
538 		ret = emulate_ldw(regs, R3(regs->iir),0);
539 		break;
540 
541 	case OPCODE_STH:
542 		ret = emulate_sth(regs, R2(regs->iir));
543 		break;
544 
545 	case OPCODE_STW:
546 	case OPCODE_STWA:
547 		ret = emulate_stw(regs, R2(regs->iir),0);
548 		break;
549 
550 #ifdef CONFIG_PA20
551 	case OPCODE_LDD_I:
552 	case OPCODE_LDDA_I:
553 	case OPCODE_LDD_S:
554 	case OPCODE_LDDA_S:
555 		ret = emulate_ldd(regs, R3(regs->iir),0);
556 		break;
557 
558 	case OPCODE_STD:
559 	case OPCODE_STDA:
560 		ret = emulate_std(regs, R2(regs->iir),0);
561 		break;
562 #endif
563 
564 	case OPCODE_FLDWX:
565 	case OPCODE_FLDWS:
566 	case OPCODE_FLDWXR:
567 	case OPCODE_FLDWSR:
568 		flop=1;
569 		ret = emulate_ldw(regs,FR3(regs->iir),1);
570 		break;
571 
572 	case OPCODE_FLDDX:
573 	case OPCODE_FLDDS:
574 		flop=1;
575 		ret = emulate_ldd(regs,R3(regs->iir),1);
576 		break;
577 
578 	case OPCODE_FSTWX:
579 	case OPCODE_FSTWS:
580 	case OPCODE_FSTWXR:
581 	case OPCODE_FSTWSR:
582 		flop=1;
583 		ret = emulate_stw(regs,FR3(regs->iir),1);
584 		break;
585 
586 	case OPCODE_FSTDX:
587 	case OPCODE_FSTDS:
588 		flop=1;
589 		ret = emulate_std(regs,R3(regs->iir),1);
590 		break;
591 
592 	case OPCODE_LDCD_I:
593 	case OPCODE_LDCW_I:
594 	case OPCODE_LDCD_S:
595 	case OPCODE_LDCW_S:
596 		ret = ERR_NOTHANDLED;	/* "undefined", but lets kill them. */
597 		break;
598 	}
599 	switch (regs->iir & OPCODE2_MASK)
600 	{
601 	case OPCODE_FLDD_L:
602 		flop=1;
603 		ret = emulate_ldd(regs,R2(regs->iir),1);
604 		break;
605 	case OPCODE_FSTD_L:
606 		flop=1;
607 		ret = emulate_std(regs, R2(regs->iir),1);
608 		break;
609 #ifdef CONFIG_PA20
610 	case OPCODE_LDD_L:
611 		ret = emulate_ldd(regs, R2(regs->iir),0);
612 		break;
613 	case OPCODE_STD_L:
614 		ret = emulate_std(regs, R2(regs->iir),0);
615 		break;
616 #endif
617 	}
618 	switch (regs->iir & OPCODE3_MASK)
619 	{
620 	case OPCODE_FLDW_L:
621 		flop=1;
622 		ret = emulate_ldw(regs, R2(regs->iir), 1);
623 		break;
624 	case OPCODE_LDW_M:
625 		ret = emulate_ldw(regs, R2(regs->iir), 0);
626 		break;
627 
628 	case OPCODE_FSTW_L:
629 		flop=1;
630 		ret = emulate_stw(regs, R2(regs->iir),1);
631 		break;
632 	case OPCODE_STW_M:
633 		ret = emulate_stw(regs, R2(regs->iir),0);
634 		break;
635 	}
636 	switch (regs->iir & OPCODE4_MASK)
637 	{
638 	case OPCODE_LDH_L:
639 		ret = emulate_ldh(regs, R2(regs->iir));
640 		break;
641 	case OPCODE_LDW_L:
642 	case OPCODE_LDWM:
643 		ret = emulate_ldw(regs, R2(regs->iir),0);
644 		break;
645 	case OPCODE_STH_L:
646 		ret = emulate_sth(regs, R2(regs->iir));
647 		break;
648 	case OPCODE_STW_L:
649 	case OPCODE_STWM:
650 		ret = emulate_stw(regs, R2(regs->iir),0);
651 		break;
652 	}
653 
654 	if (ret == 0 && modify && R1(regs->iir))
655 		regs->gr[R1(regs->iir)] = newbase;
656 
657 
658 	if (ret == ERR_NOTHANDLED)
659 		printk(KERN_CRIT "Not-handled unaligned insn 0x%08lx\n", regs->iir);
660 
661 	DPRINTF("ret = %d\n", ret);
662 
663 	if (ret)
664 	{
665 		/*
666 		 * The unaligned handler failed.
667 		 * If we were called by __get_user() or __put_user() jump
668 		 * to it's exception fixup handler instead of crashing.
669 		 */
670 		if (!user_mode(regs) && fixup_exception(regs))
671 			return;
672 
673 		printk(KERN_CRIT "Unaligned handler failed, ret = %d\n", ret);
674 		die_if_kernel("Unaligned data reference", regs, 28);
675 
676 		if (ret == ERR_PAGEFAULT)
677 		{
678 			force_sig_fault(SIGSEGV, SEGV_MAPERR,
679 					(void __user *)regs->ior);
680 		}
681 		else
682 		{
683 force_sigbus:
684 			/* couldn't handle it ... */
685 			force_sig_fault(SIGBUS, BUS_ADRALN,
686 					(void __user *)regs->ior);
687 		}
688 
689 		return;
690 	}
691 
692 	/* else we handled it, let life go on. */
693 	regs->gr[0]|=PSW_N;
694 }
695 
696 /*
697  * NB: check_unaligned() is only used for PCXS processors right
698  * now, so we only check for PA1.1 encodings at this point.
699  */
700 
701 int
702 check_unaligned(struct pt_regs *regs)
703 {
704 	unsigned long align_mask;
705 
706 	/* Get alignment mask */
707 
708 	align_mask = 0UL;
709 	switch (regs->iir & OPCODE1_MASK) {
710 
711 	case OPCODE_LDH_I:
712 	case OPCODE_LDH_S:
713 	case OPCODE_STH:
714 		align_mask = 1UL;
715 		break;
716 
717 	case OPCODE_LDW_I:
718 	case OPCODE_LDWA_I:
719 	case OPCODE_LDW_S:
720 	case OPCODE_LDWA_S:
721 	case OPCODE_STW:
722 	case OPCODE_STWA:
723 		align_mask = 3UL;
724 		break;
725 
726 	default:
727 		switch (regs->iir & OPCODE4_MASK) {
728 		case OPCODE_LDH_L:
729 		case OPCODE_STH_L:
730 			align_mask = 1UL;
731 			break;
732 		case OPCODE_LDW_L:
733 		case OPCODE_LDWM:
734 		case OPCODE_STW_L:
735 		case OPCODE_STWM:
736 			align_mask = 3UL;
737 			break;
738 		}
739 		break;
740 	}
741 
742 	return (int)(regs->ior & align_mask);
743 }
744 
745