xref: /linux/arch/parisc/kernel/unaligned.c (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
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  *    Copyright (C) 2022 Helge Deller <deller@gmx.de>
7  *    Significantly tweaked by LaMont Jones <lamont@debian.org>
8  */
9 
10 #include <linux/sched/signal.h>
11 #include <linux/signal.h>
12 #include <linux/ratelimit.h>
13 #include <linux/uaccess.h>
14 #include <linux/sysctl.h>
15 #include <asm/unaligned.h>
16 #include <asm/hardirq.h>
17 #include <asm/traps.h>
18 
19 /* #define DEBUG_UNALIGNED 1 */
20 
21 #ifdef DEBUG_UNALIGNED
22 #define DPRINTF(fmt, args...) do { printk(KERN_DEBUG "%s:%d:%s ", __FILE__, __LINE__, __func__ ); printk(KERN_DEBUG fmt, ##args ); } while (0)
23 #else
24 #define DPRINTF(fmt, args...)
25 #endif
26 
27 #define RFMT "%#08lx"
28 
29 /* 1111 1100 0000 0000 0001 0011 1100 0000 */
30 #define OPCODE1(a,b,c)	((a)<<26|(b)<<12|(c)<<6)
31 #define OPCODE2(a,b)	((a)<<26|(b)<<1)
32 #define OPCODE3(a,b)	((a)<<26|(b)<<2)
33 #define OPCODE4(a)	((a)<<26)
34 #define OPCODE1_MASK	OPCODE1(0x3f,1,0xf)
35 #define OPCODE2_MASK 	OPCODE2(0x3f,1)
36 #define OPCODE3_MASK	OPCODE3(0x3f,1)
37 #define OPCODE4_MASK    OPCODE4(0x3f)
38 
39 /* skip LDB - never unaligned (index) */
40 #define OPCODE_LDH_I	OPCODE1(0x03,0,0x1)
41 #define OPCODE_LDW_I	OPCODE1(0x03,0,0x2)
42 #define OPCODE_LDD_I	OPCODE1(0x03,0,0x3)
43 #define OPCODE_LDDA_I	OPCODE1(0x03,0,0x4)
44 #define OPCODE_LDCD_I	OPCODE1(0x03,0,0x5)
45 #define OPCODE_LDWA_I	OPCODE1(0x03,0,0x6)
46 #define OPCODE_LDCW_I	OPCODE1(0x03,0,0x7)
47 /* skip LDB - never unaligned (short) */
48 #define OPCODE_LDH_S	OPCODE1(0x03,1,0x1)
49 #define OPCODE_LDW_S	OPCODE1(0x03,1,0x2)
50 #define OPCODE_LDD_S	OPCODE1(0x03,1,0x3)
51 #define OPCODE_LDDA_S	OPCODE1(0x03,1,0x4)
52 #define OPCODE_LDCD_S	OPCODE1(0x03,1,0x5)
53 #define OPCODE_LDWA_S	OPCODE1(0x03,1,0x6)
54 #define OPCODE_LDCW_S	OPCODE1(0x03,1,0x7)
55 /* skip STB - never unaligned */
56 #define OPCODE_STH	OPCODE1(0x03,1,0x9)
57 #define OPCODE_STW	OPCODE1(0x03,1,0xa)
58 #define OPCODE_STD	OPCODE1(0x03,1,0xb)
59 /* skip STBY - never unaligned */
60 /* skip STDBY - never unaligned */
61 #define OPCODE_STWA	OPCODE1(0x03,1,0xe)
62 #define OPCODE_STDA	OPCODE1(0x03,1,0xf)
63 
64 #define OPCODE_FLDWX	OPCODE1(0x09,0,0x0)
65 #define OPCODE_FLDWXR	OPCODE1(0x09,0,0x1)
66 #define OPCODE_FSTWX	OPCODE1(0x09,0,0x8)
67 #define OPCODE_FSTWXR	OPCODE1(0x09,0,0x9)
68 #define OPCODE_FLDWS	OPCODE1(0x09,1,0x0)
69 #define OPCODE_FLDWSR	OPCODE1(0x09,1,0x1)
70 #define OPCODE_FSTWS	OPCODE1(0x09,1,0x8)
71 #define OPCODE_FSTWSR	OPCODE1(0x09,1,0x9)
72 #define OPCODE_FLDDX	OPCODE1(0x0b,0,0x0)
73 #define OPCODE_FSTDX	OPCODE1(0x0b,0,0x8)
74 #define OPCODE_FLDDS	OPCODE1(0x0b,1,0x0)
75 #define OPCODE_FSTDS	OPCODE1(0x0b,1,0x8)
76 
77 #define OPCODE_LDD_L	OPCODE2(0x14,0)
78 #define OPCODE_FLDD_L	OPCODE2(0x14,1)
79 #define OPCODE_STD_L	OPCODE2(0x1c,0)
80 #define OPCODE_FSTD_L	OPCODE2(0x1c,1)
81 
82 #define OPCODE_LDW_M	OPCODE3(0x17,1)
83 #define OPCODE_FLDW_L	OPCODE3(0x17,0)
84 #define OPCODE_FSTW_L	OPCODE3(0x1f,0)
85 #define OPCODE_STW_M	OPCODE3(0x1f,1)
86 
87 #define OPCODE_LDH_L    OPCODE4(0x11)
88 #define OPCODE_LDW_L    OPCODE4(0x12)
89 #define OPCODE_LDWM     OPCODE4(0x13)
90 #define OPCODE_STH_L    OPCODE4(0x19)
91 #define OPCODE_STW_L    OPCODE4(0x1A)
92 #define OPCODE_STWM     OPCODE4(0x1B)
93 
94 #define MAJOR_OP(i) (((i)>>26)&0x3f)
95 #define R1(i) (((i)>>21)&0x1f)
96 #define R2(i) (((i)>>16)&0x1f)
97 #define R3(i) ((i)&0x1f)
98 #define FR3(i) ((((i)&0x1f)<<1)|(((i)>>6)&1))
99 #define IM(i,n) (((i)>>1&((1<<(n-1))-1))|((i)&1?((0-1L)<<(n-1)):0))
100 #define IM5_2(i) IM((i)>>16,5)
101 #define IM5_3(i) IM((i),5)
102 #define IM14(i) IM((i),14)
103 
104 #define ERR_NOTHANDLED	-1
105 
106 int unaligned_enabled __read_mostly = 1;
107 int no_unaligned_warning __read_mostly;
108 
109 static int emulate_ldh(struct pt_regs *regs, int toreg)
110 {
111 	unsigned long saddr = regs->ior;
112 	unsigned long val = 0, temp1;
113 	ASM_EXCEPTIONTABLE_VAR(ret);
114 
115 	DPRINTF("load " RFMT ":" RFMT " to r%d for 2 bytes\n",
116 		regs->isr, regs->ior, toreg);
117 
118 	__asm__ __volatile__  (
119 "	mtsp	%4, %%sr1\n"
120 "1:	ldbs	0(%%sr1,%3), %2\n"
121 "2:	ldbs	1(%%sr1,%3), %0\n"
122 "	depw	%2, 23, 24, %0\n"
123 "3:	\n"
124 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 3b, "%1")
125 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 3b, "%1")
126 	: "+r" (val), "+r" (ret), "=&r" (temp1)
127 	: "r" (saddr), "r" (regs->isr) );
128 
129 	DPRINTF("val = " RFMT "\n", val);
130 
131 	if (toreg)
132 		regs->gr[toreg] = val;
133 
134 	return ret;
135 }
136 
137 static int emulate_ldw(struct pt_regs *regs, int toreg, int flop)
138 {
139 	unsigned long saddr = regs->ior;
140 	unsigned long val = 0, temp1, temp2;
141 	ASM_EXCEPTIONTABLE_VAR(ret);
142 
143 	DPRINTF("load " RFMT ":" RFMT " to r%d for 4 bytes\n",
144 		regs->isr, regs->ior, toreg);
145 
146 	__asm__ __volatile__  (
147 "	zdep	%4,28,2,%2\n"		/* r19=(ofs&3)*8 */
148 "	mtsp	%5, %%sr1\n"
149 "	depw	%%r0,31,2,%4\n"
150 "1:	ldw	0(%%sr1,%4),%0\n"
151 "2:	ldw	4(%%sr1,%4),%3\n"
152 "	subi	32,%2,%2\n"
153 "	mtctl	%2,11\n"
154 "	vshd	%0,%3,%0\n"
155 "3:	\n"
156 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 3b, "%1")
157 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 3b, "%1")
158 	: "+r" (val), "+r" (ret), "=&r" (temp1), "=&r" (temp2)
159 	: "r" (saddr), "r" (regs->isr) );
160 
161 	DPRINTF("val = " RFMT "\n", val);
162 
163 	if (flop)
164 		((__u32*)(regs->fr))[toreg] = val;
165 	else if (toreg)
166 		regs->gr[toreg] = val;
167 
168 	return ret;
169 }
170 static int emulate_ldd(struct pt_regs *regs, int toreg, int flop)
171 {
172 	unsigned long saddr = regs->ior;
173 	unsigned long shift, temp1;
174 	__u64 val = 0;
175 	ASM_EXCEPTIONTABLE_VAR(ret);
176 
177 	DPRINTF("load " RFMT ":" RFMT " to r%d for 8 bytes\n",
178 		regs->isr, regs->ior, toreg);
179 
180 	if (!IS_ENABLED(CONFIG_64BIT) && !flop)
181 		return ERR_NOTHANDLED;
182 
183 #ifdef CONFIG_64BIT
184 	__asm__ __volatile__  (
185 "	depd,z	%2,60,3,%3\n"		/* shift=(ofs&7)*8 */
186 "	mtsp	%5, %%sr1\n"
187 "	depd	%%r0,63,3,%2\n"
188 "1:	ldd	0(%%sr1,%2),%0\n"
189 "2:	ldd	8(%%sr1,%2),%4\n"
190 "	subi	64,%3,%3\n"
191 "	mtsar	%3\n"
192 "	shrpd	%0,%4,%%sar,%0\n"
193 "3:	\n"
194 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 3b, "%1")
195 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 3b, "%1")
196 	: "+r" (val), "+r" (ret), "+r" (saddr), "=&r" (shift), "=&r" (temp1)
197 	: "r" (regs->isr) );
198 #else
199 	__asm__ __volatile__  (
200 "	zdep	%2,29,2,%3\n"		/* shift=(ofs&3)*8 */
201 "	mtsp	%5, %%sr1\n"
202 "	dep	%%r0,31,2,%2\n"
203 "1:	ldw	0(%%sr1,%2),%0\n"
204 "2:	ldw	4(%%sr1,%2),%R0\n"
205 "3:	ldw	8(%%sr1,%2),%4\n"
206 "	subi	32,%3,%3\n"
207 "	mtsar	%3\n"
208 "	vshd	%0,%R0,%0\n"
209 "	vshd	%R0,%4,%R0\n"
210 "4:	\n"
211 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 4b, "%1")
212 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 4b, "%1")
213 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(3b, 4b, "%1")
214 	: "+r" (val), "+r" (ret), "+r" (saddr), "=&r" (shift), "=&r" (temp1)
215 	: "r" (regs->isr) );
216 #endif
217 
218 	DPRINTF("val = 0x%llx\n", val);
219 
220 	if (flop)
221 		regs->fr[toreg] = val;
222 	else if (toreg)
223 		regs->gr[toreg] = val;
224 
225 	return ret;
226 }
227 
228 static int emulate_sth(struct pt_regs *regs, int frreg)
229 {
230 	unsigned long val = regs->gr[frreg], temp1;
231 	ASM_EXCEPTIONTABLE_VAR(ret);
232 
233 	if (!frreg)
234 		val = 0;
235 
236 	DPRINTF("store r%d (" RFMT ") to " RFMT ":" RFMT " for 2 bytes\n", frreg,
237 		val, regs->isr, regs->ior);
238 
239 	__asm__ __volatile__ (
240 "	mtsp %4, %%sr1\n"
241 "	extrw,u %2, 23, 8, %1\n"
242 "1:	stb %1, 0(%%sr1, %3)\n"
243 "2:	stb %2, 1(%%sr1, %3)\n"
244 "3:	\n"
245 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 3b, "%0")
246 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 3b, "%0")
247 	: "+r" (ret), "=&r" (temp1)
248 	: "r" (val), "r" (regs->ior), "r" (regs->isr) );
249 
250 	return ret;
251 }
252 
253 static int emulate_stw(struct pt_regs *regs, int frreg, int flop)
254 {
255 	unsigned long val;
256 	ASM_EXCEPTIONTABLE_VAR(ret);
257 
258 	if (flop)
259 		val = ((__u32*)(regs->fr))[frreg];
260 	else if (frreg)
261 		val = regs->gr[frreg];
262 	else
263 		val = 0;
264 
265 	DPRINTF("store r%d (" RFMT ") to " RFMT ":" RFMT " for 4 bytes\n", frreg,
266 		val, regs->isr, regs->ior);
267 
268 
269 	__asm__ __volatile__ (
270 "	mtsp %3, %%sr1\n"
271 "	zdep	%2, 28, 2, %%r19\n"
272 "	dep	%%r0, 31, 2, %2\n"
273 "	mtsar	%%r19\n"
274 "	depwi,z	-2, %%sar, 32, %%r19\n"
275 "1:	ldw	0(%%sr1,%2),%%r20\n"
276 "2:	ldw	4(%%sr1,%2),%%r21\n"
277 "	vshd	%%r0, %1, %%r22\n"
278 "	vshd	%1, %%r0, %%r1\n"
279 "	and	%%r20, %%r19, %%r20\n"
280 "	andcm	%%r21, %%r19, %%r21\n"
281 "	or	%%r22, %%r20, %%r20\n"
282 "	or	%%r1, %%r21, %%r21\n"
283 "	stw	%%r20,0(%%sr1,%2)\n"
284 "	stw	%%r21,4(%%sr1,%2)\n"
285 "3:	\n"
286 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 3b, "%0")
287 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 3b, "%0")
288 	: "+r" (ret)
289 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
290 	: "r19", "r20", "r21", "r22", "r1" );
291 
292 	return ret;
293 }
294 static int emulate_std(struct pt_regs *regs, int frreg, int flop)
295 {
296 	__u64 val;
297 	ASM_EXCEPTIONTABLE_VAR(ret);
298 
299 	if (flop)
300 		val = regs->fr[frreg];
301 	else if (frreg)
302 		val = regs->gr[frreg];
303 	else
304 		val = 0;
305 
306 	DPRINTF("store r%d (0x%016llx) to " RFMT ":" RFMT " for 8 bytes\n", frreg,
307 		val,  regs->isr, regs->ior);
308 
309 	if (!IS_ENABLED(CONFIG_64BIT) && !flop)
310 		return ERR_NOTHANDLED;
311 
312 #ifdef CONFIG_64BIT
313 	__asm__ __volatile__ (
314 "	mtsp %3, %%sr1\n"
315 "	depd,z	%2, 60, 3, %%r19\n"
316 "	depd	%%r0, 63, 3, %2\n"
317 "	mtsar	%%r19\n"
318 "	depdi,z	-2, %%sar, 64, %%r19\n"
319 "1:	ldd	0(%%sr1,%2),%%r20\n"
320 "2:	ldd	8(%%sr1,%2),%%r21\n"
321 "	shrpd	%%r0, %1, %%sar, %%r22\n"
322 "	shrpd	%1, %%r0, %%sar, %%r1\n"
323 "	and	%%r20, %%r19, %%r20\n"
324 "	andcm	%%r21, %%r19, %%r21\n"
325 "	or	%%r22, %%r20, %%r20\n"
326 "	or	%%r1, %%r21, %%r21\n"
327 "3:	std	%%r20,0(%%sr1,%2)\n"
328 "4:	std	%%r21,8(%%sr1,%2)\n"
329 "5:	\n"
330 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 5b, "%0")
331 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 5b, "%0")
332 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(3b, 5b, "%0")
333 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(4b, 5b, "%0")
334 	: "+r" (ret)
335 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
336 	: "r19", "r20", "r21", "r22", "r1" );
337 #else
338     {
339 	__asm__ __volatile__ (
340 "	mtsp	%3, %%sr1\n"
341 "	zdep	%R1, 29, 2, %%r19\n"
342 "	dep	%%r0, 31, 2, %2\n"
343 "	mtsar	%%r19\n"
344 "	zvdepi	-2, 32, %%r19\n"
345 "1:	ldw	0(%%sr1,%2),%%r20\n"
346 "2:	ldw	8(%%sr1,%2),%%r21\n"
347 "	vshd	%1, %R1, %%r1\n"
348 "	vshd	%%r0, %1, %1\n"
349 "	vshd	%R1, %%r0, %R1\n"
350 "	and	%%r20, %%r19, %%r20\n"
351 "	andcm	%%r21, %%r19, %%r21\n"
352 "	or	%1, %%r20, %1\n"
353 "	or	%R1, %%r21, %R1\n"
354 "3:	stw	%1,0(%%sr1,%2)\n"
355 "4:	stw	%%r1,4(%%sr1,%2)\n"
356 "5:	stw	%R1,8(%%sr1,%2)\n"
357 "6:	\n"
358 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 6b, "%0")
359 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 6b, "%0")
360 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(3b, 6b, "%0")
361 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(4b, 6b, "%0")
362 	ASM_EXCEPTIONTABLE_ENTRY_EFAULT(5b, 6b, "%0")
363 	: "+r" (ret)
364 	: "r" (val), "r" (regs->ior), "r" (regs->isr)
365 	: "r19", "r20", "r21", "r1" );
366     }
367 #endif
368 
369 	return ret;
370 }
371 
372 void handle_unaligned(struct pt_regs *regs)
373 {
374 	static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
375 	unsigned long newbase = R1(regs->iir)?regs->gr[R1(regs->iir)]:0;
376 	int modify = 0;
377 	int ret = ERR_NOTHANDLED;
378 
379 	__inc_irq_stat(irq_unaligned_count);
380 
381 	/* log a message with pacing */
382 	if (user_mode(regs)) {
383 		if (current->thread.flags & PARISC_UAC_SIGBUS) {
384 			goto force_sigbus;
385 		}
386 
387 		if (!(current->thread.flags & PARISC_UAC_NOPRINT) &&
388 			__ratelimit(&ratelimit)) {
389 			printk(KERN_WARNING "%s(%d): unaligned access to " RFMT
390 				" at ip " RFMT " (iir " RFMT ")\n",
391 				current->comm, task_pid_nr(current), regs->ior,
392 				regs->iaoq[0], regs->iir);
393 #ifdef DEBUG_UNALIGNED
394 			show_regs(regs);
395 #endif
396 		}
397 
398 		if (!unaligned_enabled)
399 			goto force_sigbus;
400 	} else {
401 		static DEFINE_RATELIMIT_STATE(kernel_ratelimit, 5 * HZ, 5);
402 		if (!(current->thread.flags & PARISC_UAC_NOPRINT) &&
403 			!no_unaligned_warning &&
404 			__ratelimit(&kernel_ratelimit))
405 			pr_warn("Kernel: unaligned access to " RFMT " in %pS "
406 					"(iir " RFMT ")\n",
407 				regs->ior, (void *)regs->iaoq[0], regs->iir);
408 	}
409 
410 	/* handle modification - OK, it's ugly, see the instruction manual */
411 	switch (MAJOR_OP(regs->iir))
412 	{
413 	case 0x03:
414 	case 0x09:
415 	case 0x0b:
416 		if (regs->iir&0x20)
417 		{
418 			modify = 1;
419 			if (regs->iir&0x1000)		/* short loads */
420 				if (regs->iir&0x200)
421 					newbase += IM5_3(regs->iir);
422 				else
423 					newbase += IM5_2(regs->iir);
424 			else if (regs->iir&0x2000)	/* scaled indexed */
425 			{
426 				int shift=0;
427 				switch (regs->iir & OPCODE1_MASK)
428 				{
429 				case OPCODE_LDH_I:
430 					shift= 1; break;
431 				case OPCODE_LDW_I:
432 					shift= 2; break;
433 				case OPCODE_LDD_I:
434 				case OPCODE_LDDA_I:
435 					shift= 3; break;
436 				}
437 				newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0)<<shift;
438 			} else				/* simple indexed */
439 				newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0);
440 		}
441 		break;
442 	case 0x13:
443 	case 0x1b:
444 		modify = 1;
445 		newbase += IM14(regs->iir);
446 		break;
447 	case 0x14:
448 	case 0x1c:
449 		if (regs->iir&8)
450 		{
451 			modify = 1;
452 			newbase += IM14(regs->iir&~0xe);
453 		}
454 		break;
455 	case 0x16:
456 	case 0x1e:
457 		modify = 1;
458 		newbase += IM14(regs->iir&6);
459 		break;
460 	case 0x17:
461 	case 0x1f:
462 		if (regs->iir&4)
463 		{
464 			modify = 1;
465 			newbase += IM14(regs->iir&~4);
466 		}
467 		break;
468 	}
469 
470 	/* TODO: make this cleaner... */
471 	switch (regs->iir & OPCODE1_MASK)
472 	{
473 	case OPCODE_LDH_I:
474 	case OPCODE_LDH_S:
475 		ret = emulate_ldh(regs, R3(regs->iir));
476 		break;
477 
478 	case OPCODE_LDW_I:
479 	case OPCODE_LDWA_I:
480 	case OPCODE_LDW_S:
481 	case OPCODE_LDWA_S:
482 		ret = emulate_ldw(regs, R3(regs->iir), 0);
483 		break;
484 
485 	case OPCODE_STH:
486 		ret = emulate_sth(regs, R2(regs->iir));
487 		break;
488 
489 	case OPCODE_STW:
490 	case OPCODE_STWA:
491 		ret = emulate_stw(regs, R2(regs->iir), 0);
492 		break;
493 
494 #ifdef CONFIG_64BIT
495 	case OPCODE_LDD_I:
496 	case OPCODE_LDDA_I:
497 	case OPCODE_LDD_S:
498 	case OPCODE_LDDA_S:
499 		ret = emulate_ldd(regs, R3(regs->iir), 0);
500 		break;
501 
502 	case OPCODE_STD:
503 	case OPCODE_STDA:
504 		ret = emulate_std(regs, R2(regs->iir), 0);
505 		break;
506 #endif
507 
508 	case OPCODE_FLDWX:
509 	case OPCODE_FLDWS:
510 	case OPCODE_FLDWXR:
511 	case OPCODE_FLDWSR:
512 		ret = emulate_ldw(regs, FR3(regs->iir), 1);
513 		break;
514 
515 	case OPCODE_FLDDX:
516 	case OPCODE_FLDDS:
517 		ret = emulate_ldd(regs, R3(regs->iir), 1);
518 		break;
519 
520 	case OPCODE_FSTWX:
521 	case OPCODE_FSTWS:
522 	case OPCODE_FSTWXR:
523 	case OPCODE_FSTWSR:
524 		ret = emulate_stw(regs, FR3(regs->iir), 1);
525 		break;
526 
527 	case OPCODE_FSTDX:
528 	case OPCODE_FSTDS:
529 		ret = emulate_std(regs, R3(regs->iir), 1);
530 		break;
531 
532 	case OPCODE_LDCD_I:
533 	case OPCODE_LDCW_I:
534 	case OPCODE_LDCD_S:
535 	case OPCODE_LDCW_S:
536 		ret = ERR_NOTHANDLED;	/* "undefined", but lets kill them. */
537 		break;
538 	}
539 	switch (regs->iir & OPCODE2_MASK)
540 	{
541 	case OPCODE_FLDD_L:
542 		ret = emulate_ldd(regs,R2(regs->iir),1);
543 		break;
544 	case OPCODE_FSTD_L:
545 		ret = emulate_std(regs, R2(regs->iir),1);
546 		break;
547 #ifdef CONFIG_64BIT
548 	case OPCODE_LDD_L:
549 		ret = emulate_ldd(regs, R2(regs->iir),0);
550 		break;
551 	case OPCODE_STD_L:
552 		ret = emulate_std(regs, R2(regs->iir),0);
553 		break;
554 #endif
555 	}
556 	switch (regs->iir & OPCODE3_MASK)
557 	{
558 	case OPCODE_FLDW_L:
559 		ret = emulate_ldw(regs, R2(regs->iir), 1);
560 		break;
561 	case OPCODE_LDW_M:
562 		ret = emulate_ldw(regs, R2(regs->iir), 0);
563 		break;
564 
565 	case OPCODE_FSTW_L:
566 		ret = emulate_stw(regs, R2(regs->iir),1);
567 		break;
568 	case OPCODE_STW_M:
569 		ret = emulate_stw(regs, R2(regs->iir),0);
570 		break;
571 	}
572 	switch (regs->iir & OPCODE4_MASK)
573 	{
574 	case OPCODE_LDH_L:
575 		ret = emulate_ldh(regs, R2(regs->iir));
576 		break;
577 	case OPCODE_LDW_L:
578 	case OPCODE_LDWM:
579 		ret = emulate_ldw(regs, R2(regs->iir),0);
580 		break;
581 	case OPCODE_STH_L:
582 		ret = emulate_sth(regs, R2(regs->iir));
583 		break;
584 	case OPCODE_STW_L:
585 	case OPCODE_STWM:
586 		ret = emulate_stw(regs, R2(regs->iir),0);
587 		break;
588 	}
589 
590 	if (ret == 0 && modify && R1(regs->iir))
591 		regs->gr[R1(regs->iir)] = newbase;
592 
593 
594 	if (ret == ERR_NOTHANDLED)
595 		printk(KERN_CRIT "Not-handled unaligned insn 0x%08lx\n", regs->iir);
596 
597 	DPRINTF("ret = %d\n", ret);
598 
599 	if (ret)
600 	{
601 		/*
602 		 * The unaligned handler failed.
603 		 * If we were called by __get_user() or __put_user() jump
604 		 * to it's exception fixup handler instead of crashing.
605 		 */
606 		if (!user_mode(regs) && fixup_exception(regs))
607 			return;
608 
609 		printk(KERN_CRIT "Unaligned handler failed, ret = %d\n", ret);
610 		die_if_kernel("Unaligned data reference", regs, 28);
611 
612 		if (ret == -EFAULT)
613 		{
614 			force_sig_fault(SIGSEGV, SEGV_MAPERR,
615 					(void __user *)regs->ior);
616 		}
617 		else
618 		{
619 force_sigbus:
620 			/* couldn't handle it ... */
621 			force_sig_fault(SIGBUS, BUS_ADRALN,
622 					(void __user *)regs->ior);
623 		}
624 
625 		return;
626 	}
627 
628 	/* else we handled it, let life go on. */
629 	regs->gr[0]|=PSW_N;
630 }
631 
632 /*
633  * NB: check_unaligned() is only used for PCXS processors right
634  * now, so we only check for PA1.1 encodings at this point.
635  */
636 
637 int
638 check_unaligned(struct pt_regs *regs)
639 {
640 	unsigned long align_mask;
641 
642 	/* Get alignment mask */
643 
644 	align_mask = 0UL;
645 	switch (regs->iir & OPCODE1_MASK) {
646 
647 	case OPCODE_LDH_I:
648 	case OPCODE_LDH_S:
649 	case OPCODE_STH:
650 		align_mask = 1UL;
651 		break;
652 
653 	case OPCODE_LDW_I:
654 	case OPCODE_LDWA_I:
655 	case OPCODE_LDW_S:
656 	case OPCODE_LDWA_S:
657 	case OPCODE_STW:
658 	case OPCODE_STWA:
659 		align_mask = 3UL;
660 		break;
661 
662 	default:
663 		switch (regs->iir & OPCODE4_MASK) {
664 		case OPCODE_LDH_L:
665 		case OPCODE_STH_L:
666 			align_mask = 1UL;
667 			break;
668 		case OPCODE_LDW_L:
669 		case OPCODE_LDWM:
670 		case OPCODE_STW_L:
671 		case OPCODE_STWM:
672 			align_mask = 3UL;
673 			break;
674 		}
675 		break;
676 	}
677 
678 	return (int)(regs->ior & align_mask);
679 }
680 
681