1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Exception handling for Microblaze
4 *
5 * Rewriten interrupt handling
6 *
7 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
8 * Copyright (C) 2008-2009 PetaLogix
9 *
10 * uClinux customisation (C) 2005 John Williams
11 *
12 * MMU code derived from arch/ppc/kernel/head_4xx.S:
13 *	Copyright (C) 1995-1996 Gary Thomas <gdt@linuxppc.org>
14 *		Initial PowerPC version.
15 *	Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
16 *		Rewritten for PReP
17 *	Copyright (C) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
18 *		Low-level exception handers, MMU support, and rewrite.
19 *	Copyright (C) 1997 Dan Malek <dmalek@jlc.net>
20 *		PowerPC 8xx modifications.
21 *	Copyright (C) 1998-1999 TiVo, Inc.
22 *		PowerPC 403GCX modifications.
23 *	Copyright (C) 1999 Grant Erickson <grant@lcse.umn.edu>
24 *		PowerPC 403GCX/405GP modifications.
25 *	Copyright 2000 MontaVista Software Inc.
26 *		PPC405 modifications
27 *	PowerPC 403GCX/405GP modifications.
28 *		Author: MontaVista Software, Inc.
29 *		frank_rowand@mvista.com or source@mvista.com
30 *		debbie_chu@mvista.com
31 *
32 * Original code
33 * Copyright (C) 2004 Xilinx, Inc.
34 */
35
36/*
37 * Here are the handlers which don't require enabling translation
38 * and calling other kernel code thus we can keep their design very simple
39 * and do all processing in real mode. All what they need is a valid current
40 * (that is an issue for the CONFIG_REGISTER_TASK_PTR case)
41 * This handlers use r3,r4,r5,r6 and optionally r[current] to work therefore
42 * these registers are saved/restored
43 * The handlers which require translation are in entry.S --KAA
44 *
45 * Microblaze HW Exception Handler
46 * - Non self-modifying exception handler for the following exception conditions
47 *   - Unalignment
48 *   - Instruction bus error
49 *   - Data bus error
50 *   - Illegal instruction opcode
51 *   - Divide-by-zero
52 *
53 *   - Privileged instruction exception (MMU)
54 *   - Data storage exception (MMU)
55 *   - Instruction storage exception (MMU)
56 *   - Data TLB miss exception (MMU)
57 *   - Instruction TLB miss exception (MMU)
58 *
59 * Note we disable interrupts during exception handling, otherwise we will
60 * possibly get multiple re-entrancy if interrupt handles themselves cause
61 * exceptions. JW
62 */
63
64#include <asm/exceptions.h>
65#include <asm/unistd.h>
66#include <asm/page.h>
67
68#include <asm/entry.h>
69#include <asm/current.h>
70#include <linux/linkage.h>
71
72#include <asm/mmu.h>
73#include <asm/pgtable.h>
74#include <asm/signal.h>
75#include <asm/registers.h>
76#include <asm/asm-offsets.h>
77
78#undef DEBUG
79
80/* Helpful Macros */
81#define NUM_TO_REG(num)		r ## num
82
83#ifdef CONFIG_MMU
84	#define RESTORE_STATE			\
85		lwi	r5, r1, 0;		\
86		mts	rmsr, r5;		\
87		nop;				\
88		lwi	r3, r1, PT_R3;		\
89		lwi	r4, r1, PT_R4;		\
90		lwi	r5, r1, PT_R5;		\
91		lwi	r6, r1, PT_R6;		\
92		lwi	r11, r1, PT_R11;	\
93		lwi	r31, r1, PT_R31;	\
94		lwi	r1, r1, PT_R1;
95#endif /* CONFIG_MMU */
96
97#define LWREG_NOP			\
98	bri	ex_handler_unhandled;	\
99	nop;
100
101#define SWREG_NOP			\
102	bri	ex_handler_unhandled;	\
103	nop;
104
105/* FIXME this is weird - for noMMU kernel is not possible to use brid
106 * instruction which can shorten executed time
107 */
108
109/* r3 is the source */
110#define R3_TO_LWREG_V(regnum)				\
111	swi	r3, r1, 4 * regnum;				\
112	bri	ex_handler_done;
113
114/* r3 is the source */
115#define R3_TO_LWREG(regnum)				\
116	or	NUM_TO_REG (regnum), r0, r3;		\
117	bri	ex_handler_done;
118
119/* r3 is the target */
120#define SWREG_TO_R3_V(regnum)				\
121	lwi	r3, r1, 4 * regnum;				\
122	bri	ex_sw_tail;
123
124/* r3 is the target */
125#define SWREG_TO_R3(regnum)				\
126	or	r3, r0, NUM_TO_REG (regnum);		\
127	bri	ex_sw_tail;
128
129#ifdef CONFIG_MMU
130	#define R3_TO_LWREG_VM_V(regnum)		\
131		brid	ex_lw_end_vm;			\
132		swi	r3, r7, 4 * regnum;
133
134	#define R3_TO_LWREG_VM(regnum)			\
135		brid	ex_lw_end_vm;			\
136		or	NUM_TO_REG (regnum), r0, r3;
137
138	#define SWREG_TO_R3_VM_V(regnum)		\
139		brid	ex_sw_tail_vm;			\
140		lwi	r3, r7, 4 * regnum;
141
142	#define SWREG_TO_R3_VM(regnum)			\
143		brid	ex_sw_tail_vm;			\
144		or	r3, r0, NUM_TO_REG (regnum);
145
146	/* Shift right instruction depending on available configuration */
147	#if CONFIG_XILINX_MICROBLAZE0_USE_BARREL == 0
148	/* Only the used shift constants defined here - add more if needed */
149	#define BSRLI2(rD, rA)				\
150		srl rD, rA;		/* << 1 */	\
151		srl rD, rD;		/* << 2 */
152	#define BSRLI4(rD, rA)		\
153		BSRLI2(rD, rA);		\
154		BSRLI2(rD, rD)
155	#define BSRLI10(rD, rA)				\
156		srl rD, rA;		/* << 1 */	\
157		srl rD, rD;		/* << 2 */	\
158		srl rD, rD;		/* << 3 */	\
159		srl rD, rD;		/* << 4 */	\
160		srl rD, rD;		/* << 5 */	\
161		srl rD, rD;		/* << 6 */	\
162		srl rD, rD;		/* << 7 */	\
163		srl rD, rD;		/* << 8 */	\
164		srl rD, rD;		/* << 9 */	\
165		srl rD, rD		/* << 10 */
166	#define BSRLI20(rD, rA)		\
167		BSRLI10(rD, rA);	\
168		BSRLI10(rD, rD)
169
170	.macro	bsrli, rD, rA, IMM
171	.if (\IMM) == 2
172		BSRLI2(\rD, \rA)
173	.elseif (\IMM) == 10
174		BSRLI10(\rD, \rA)
175	.elseif (\IMM) == 12
176		BSRLI2(\rD, \rA)
177		BSRLI10(\rD, \rD)
178	.elseif (\IMM) == 14
179		BSRLI4(\rD, \rA)
180		BSRLI10(\rD, \rD)
181	.elseif (\IMM) == 20
182		BSRLI20(\rD, \rA)
183	.elseif (\IMM) == 24
184		BSRLI4(\rD, \rA)
185		BSRLI20(\rD, \rD)
186	.elseif (\IMM) == 28
187		BSRLI4(\rD, \rA)
188		BSRLI4(\rD, \rD)
189		BSRLI20(\rD, \rD)
190	.else
191	.error "BSRLI shift macros \IMM"
192	.endif
193	.endm
194	#endif
195
196#endif /* CONFIG_MMU */
197
198.extern other_exception_handler /* Defined in exception.c */
199
200/*
201 * hw_exception_handler - Handler for exceptions
202 *
203 * Exception handler notes:
204 * - Handles all exceptions
205 * - Does not handle unaligned exceptions during load into r17, r1, r0.
206 * - Does not handle unaligned exceptions during store from r17 (cannot be
207 *   done) and r1 (slows down common case)
208 *
209 *  Relevant register structures
210 *
211 *  EAR - |----|----|----|----|----|----|----|----|
212 *      - <  ##   32 bit faulting address     ##  >
213 *
214 *  ESR - |----|----|----|----|----| - | - |-----|-----|
215 *      -                            W   S   REG   EXC
216 *
217 *
218 * STACK FRAME STRUCTURE (for CONFIG_MMU=n)
219 * ----------------------------------------
220 *
221 *      +-------------+         + 0
222 *      |     MSR     |
223 *      +-------------+         + 4
224 *      |     r1      |
225 *      |      .      |
226 *      |      .      |
227 *      |      .      |
228 *      |      .      |
229 *      |     r18     |
230 *      +-------------+         + 76
231 *      |      .      |
232 *      |      .      |
233 *
234 * MMU kernel uses the same 'pt_pool_space' pointed space
235 * which is used for storing register values - noMMu style was, that values were
236 * stored in stack but in case of failure you lost information about register.
237 * Currently you can see register value in memory in specific place.
238 * In compare to with previous solution the speed should be the same.
239 *
240 * MMU exception handler has different handling compare to no MMU kernel.
241 * Exception handler use jump table for directing of what happen. For MMU kernel
242 * is this approach better because MMU relate exception are handled by asm code
243 * in this file. In compare to with MMU expect of unaligned exception
244 * is everything handled by C code.
245 */
246
247/*
248 * every of these handlers is entered having R3/4/5/6/11/current saved on stack
249 * and clobbered so care should be taken to restore them if someone is going to
250 * return from exception
251 */
252
253/* wrappers to restore state before coming to entry.S */
254#ifdef CONFIG_MMU
255.section .data
256.align 4
257pt_pool_space:
258	.space	PT_SIZE
259
260#ifdef DEBUG
261/* Create space for exception counting. */
262.section .data
263.global exception_debug_table
264.align 4
265exception_debug_table:
266	/* Look at exception vector table. There is 32 exceptions * word size */
267	.space	(32 * 4)
268#endif /* DEBUG */
269
270.section .rodata
271.align 4
272_MB_HW_ExceptionVectorTable:
273/*  0 - Undefined */
274	.long	TOPHYS(ex_handler_unhandled)
275/*  1 - Unaligned data access exception */
276	.long	TOPHYS(handle_unaligned_ex)
277/*  2 - Illegal op-code exception */
278	.long	TOPHYS(full_exception_trapw)
279/*  3 - Instruction bus error exception */
280	.long	TOPHYS(full_exception_trapw)
281/*  4 - Data bus error exception */
282	.long	TOPHYS(full_exception_trapw)
283/*  5 - Divide by zero exception */
284	.long	TOPHYS(full_exception_trapw)
285/*  6 - Floating point unit exception */
286	.long	TOPHYS(full_exception_trapw)
287/*  7 - Privileged instruction exception */
288	.long	TOPHYS(full_exception_trapw)
289/*  8 - 15 - Undefined */
290	.long	TOPHYS(ex_handler_unhandled)
291	.long	TOPHYS(ex_handler_unhandled)
292	.long	TOPHYS(ex_handler_unhandled)
293	.long	TOPHYS(ex_handler_unhandled)
294	.long	TOPHYS(ex_handler_unhandled)
295	.long	TOPHYS(ex_handler_unhandled)
296	.long	TOPHYS(ex_handler_unhandled)
297	.long	TOPHYS(ex_handler_unhandled)
298/* 16 - Data storage exception */
299	.long	TOPHYS(handle_data_storage_exception)
300/* 17 - Instruction storage exception */
301	.long	TOPHYS(handle_instruction_storage_exception)
302/* 18 - Data TLB miss exception */
303	.long	TOPHYS(handle_data_tlb_miss_exception)
304/* 19 - Instruction TLB miss exception */
305	.long	TOPHYS(handle_instruction_tlb_miss_exception)
306/* 20 - 31 - Undefined */
307	.long	TOPHYS(ex_handler_unhandled)
308	.long	TOPHYS(ex_handler_unhandled)
309	.long	TOPHYS(ex_handler_unhandled)
310	.long	TOPHYS(ex_handler_unhandled)
311	.long	TOPHYS(ex_handler_unhandled)
312	.long	TOPHYS(ex_handler_unhandled)
313	.long	TOPHYS(ex_handler_unhandled)
314	.long	TOPHYS(ex_handler_unhandled)
315	.long	TOPHYS(ex_handler_unhandled)
316	.long	TOPHYS(ex_handler_unhandled)
317	.long	TOPHYS(ex_handler_unhandled)
318	.long	TOPHYS(ex_handler_unhandled)
319#endif
320
321.global _hw_exception_handler
322.section .text
323.align 4
324.ent _hw_exception_handler
325_hw_exception_handler:
326#ifndef CONFIG_MMU
327	addik	r1, r1, -(EX_HANDLER_STACK_SIZ); /* Create stack frame */
328#else
329	swi	r1, r0, TOPHYS(pt_pool_space + PT_R1); /* GET_SP */
330	/* Save date to kernel memory. Here is the problem
331	 * when you came from user space */
332	ori	r1, r0, TOPHYS(pt_pool_space);
333#endif
334	swi	r3, r1, PT_R3
335	swi	r4, r1, PT_R4
336	swi	r5, r1, PT_R5
337	swi	r6, r1, PT_R6
338
339#ifdef CONFIG_MMU
340	swi	r11, r1, PT_R11
341	swi	r31, r1, PT_R31
342	lwi	r31, r0, TOPHYS(PER_CPU(CURRENT_SAVE)) /* get saved current */
343#endif
344
345	mfs	r5, rmsr;
346	nop
347	swi	r5, r1, 0;
348	mfs	r4, resr
349	nop
350	mfs	r3, rear;
351	nop
352
353#ifndef CONFIG_MMU
354	andi	r5, r4, 0x1000;		/* Check ESR[DS] */
355	beqi	r5, not_in_delay_slot;	/* Branch if ESR[DS] not set */
356	mfs	r17, rbtr;	/* ESR[DS] set - return address in BTR */
357	nop
358not_in_delay_slot:
359	swi	r17, r1, PT_R17
360#endif
361
362	andi	r5, r4, 0x1F;		/* Extract ESR[EXC] */
363
364#ifdef CONFIG_MMU
365	/* Calculate exception vector offset = r5 << 2 */
366	addk	r6, r5, r5; /* << 1 */
367	addk	r6, r6, r6; /* << 2 */
368
369#ifdef DEBUG
370/* counting which exception happen */
371	lwi	r5, r0, TOPHYS(exception_debug_table)
372	addi	r5, r5, 1
373	swi	r5, r0, TOPHYS(exception_debug_table)
374	lwi	r5, r6, TOPHYS(exception_debug_table)
375	addi	r5, r5, 1
376	swi	r5, r6, TOPHYS(exception_debug_table)
377#endif
378/* end */
379	/* Load the HW Exception vector */
380	lwi	r6, r6, TOPHYS(_MB_HW_ExceptionVectorTable)
381	bra	r6
382
383full_exception_trapw:
384	RESTORE_STATE
385	bri	full_exception_trap
386#else
387	/* Exceptions enabled here. This will allow nested exceptions */
388	mfs	r6, rmsr;
389	nop
390	swi	r6, r1, 0; /* RMSR_OFFSET */
391	ori	r6, r6, 0x100; /* Turn ON the EE bit */
392	andi	r6, r6, ~2; /* Disable interrupts */
393	mts	rmsr, r6;
394	nop
395
396	xori	r6, r5, 1; /* 00001 = Unaligned Exception */
397	/* Jump to unalignment exception handler */
398	beqi	r6, handle_unaligned_ex;
399
400handle_other_ex: /* Handle Other exceptions here */
401	/* Save other volatiles before we make procedure calls below */
402	swi	r7, r1, PT_R7
403	swi	r8, r1, PT_R8
404	swi	r9, r1, PT_R9
405	swi	r10, r1, PT_R10
406	swi	r11, r1, PT_R11
407	swi	r12, r1, PT_R12
408	swi	r14, r1, PT_R14
409	swi	r15, r1, PT_R15
410	swi	r18, r1, PT_R18
411
412	or	r5, r1, r0
413	andi	r6, r4, 0x1F; /* Load ESR[EC] */
414	lwi	r7, r0, PER_CPU(KM) /* MS: saving current kernel mode to regs */
415	swi	r7, r1, PT_MODE
416	mfs	r7, rfsr
417	nop
418	addk	r8, r17, r0; /* Load exception address */
419	bralid	r15, full_exception; /* Branch to the handler */
420	nop;
421	mts	rfsr, r0;	/* Clear sticky fsr */
422	nop
423
424	/*
425	 * Trigger execution of the signal handler by enabling
426	 * interrupts and calling an invalid syscall.
427	 */
428	mfs	r5, rmsr;
429	nop
430	ori	r5, r5, 2;
431	mts	rmsr, r5; /* enable interrupt */
432	nop
433	addi	r12, r0, __NR_syscalls;
434	brki	r14, 0x08;
435	mfs	r5, rmsr; /* disable interrupt */
436	nop
437	andi	r5, r5, ~2;
438	mts	rmsr, r5;
439	nop
440
441	lwi	r7, r1, PT_R7
442	lwi	r8, r1, PT_R8
443	lwi	r9, r1, PT_R9
444	lwi	r10, r1, PT_R10
445	lwi	r11, r1, PT_R11
446	lwi	r12, r1, PT_R12
447	lwi	r14, r1, PT_R14
448	lwi	r15, r1, PT_R15
449	lwi	r18, r1, PT_R18
450
451	bri	ex_handler_done; /* Complete exception handling */
452#endif
453
454/* 0x01 - Unaligned data access exception
455 * This occurs when a word access is not aligned on a word boundary,
456 * or when a 16-bit access is not aligned on a 16-bit boundary.
457 * This handler perform the access, and returns, except for MMU when
458 * the unaligned address is last on a 4k page or the physical address is
459 * not found in the page table, in which case unaligned_data_trap is called.
460 */
461handle_unaligned_ex:
462	/* Working registers already saved: R3, R4, R5, R6
463	 *  R4 = ESR
464	 *  R3 = EAR
465	 */
466#ifdef CONFIG_MMU
467	andi	r6, r4, 0x1000			/* Check ESR[DS] */
468	beqi	r6, _no_delayslot		/* Branch if ESR[DS] not set */
469	mfs	r17, rbtr;	/* ESR[DS] set - return address in BTR */
470	nop
471_no_delayslot:
472	/* jump to high level unaligned handler */
473	RESTORE_STATE;
474	bri	unaligned_data_trap
475#endif
476	andi	r6, r4, 0x3E0; /* Mask and extract the register operand */
477	srl	r6, r6; /* r6 >> 5 */
478	srl	r6, r6;
479	srl	r6, r6;
480	srl	r6, r6;
481	srl	r6, r6;
482	/* Store the register operand in a temporary location */
483	sbi	r6, r0, TOPHYS(ex_reg_op);
484
485	andi	r6, r4, 0x400; /* Extract ESR[S] */
486	bnei	r6, ex_sw;
487ex_lw:
488	andi	r6, r4, 0x800; /* Extract ESR[W] */
489	beqi	r6, ex_lhw;
490	lbui	r5, r3, 0; /* Exception address in r3 */
491	/* Load a word, byte-by-byte from destination address
492		and save it in tmp space */
493	sbi	r5, r0, TOPHYS(ex_tmp_data_loc_0);
494	lbui	r5, r3, 1;
495	sbi	r5, r0, TOPHYS(ex_tmp_data_loc_1);
496	lbui	r5, r3, 2;
497	sbi	r5, r0, TOPHYS(ex_tmp_data_loc_2);
498	lbui	r5, r3, 3;
499	sbi	r5, r0, TOPHYS(ex_tmp_data_loc_3);
500	/* Get the destination register value into r4 */
501	lwi	r4, r0, TOPHYS(ex_tmp_data_loc_0);
502	bri	ex_lw_tail;
503ex_lhw:
504	lbui	r5, r3, 0; /* Exception address in r3 */
505	/* Load a half-word, byte-by-byte from destination
506		address and save it in tmp space */
507	sbi	r5, r0, TOPHYS(ex_tmp_data_loc_0);
508	lbui	r5, r3, 1;
509	sbi	r5, r0, TOPHYS(ex_tmp_data_loc_1);
510	/* Get the destination register value into r4 */
511	lhui	r4, r0, TOPHYS(ex_tmp_data_loc_0);
512ex_lw_tail:
513	/* Get the destination register number into r5 */
514	lbui	r5, r0, TOPHYS(ex_reg_op);
515	/* Form load_word jump table offset (lw_table + (8 * regnum)) */
516	addik	r6, r0, TOPHYS(lw_table);
517	addk	r5, r5, r5;
518	addk	r5, r5, r5;
519	addk	r5, r5, r5;
520	addk	r5, r5, r6;
521	bra	r5;
522ex_lw_end: /* Exception handling of load word, ends */
523ex_sw:
524	/* Get the destination register number into r5 */
525	lbui	r5, r0, TOPHYS(ex_reg_op);
526	/* Form store_word jump table offset (sw_table + (8 * regnum)) */
527	addik	r6, r0, TOPHYS(sw_table);
528	add	r5, r5, r5;
529	add	r5, r5, r5;
530	add	r5, r5, r5;
531	add	r5, r5, r6;
532	bra	r5;
533ex_sw_tail:
534	mfs	r6, resr;
535	nop
536	andi	r6, r6, 0x800; /* Extract ESR[W] */
537	beqi	r6, ex_shw;
538	/* Get the word - delay slot */
539	swi	r4, r0, TOPHYS(ex_tmp_data_loc_0);
540	/* Store the word, byte-by-byte into destination address */
541	lbui	r4, r0, TOPHYS(ex_tmp_data_loc_0);
542	sbi	r4, r3, 0;
543	lbui	r4, r0, TOPHYS(ex_tmp_data_loc_1);
544	sbi	r4, r3, 1;
545	lbui	r4, r0, TOPHYS(ex_tmp_data_loc_2);
546	sbi	r4, r3, 2;
547	lbui	r4, r0, TOPHYS(ex_tmp_data_loc_3);
548	sbi	r4, r3, 3;
549	bri	ex_handler_done;
550
551ex_shw:
552	/* Store the lower half-word, byte-by-byte into destination address */
553	swi	r4, r0, TOPHYS(ex_tmp_data_loc_0);
554	lbui	r4, r0, TOPHYS(ex_tmp_data_loc_2);
555	sbi	r4, r3, 0;
556	lbui	r4, r0, TOPHYS(ex_tmp_data_loc_3);
557	sbi	r4, r3, 1;
558ex_sw_end: /* Exception handling of store word, ends. */
559
560ex_handler_done:
561#ifndef CONFIG_MMU
562	lwi	r5, r1, 0 /* RMSR */
563	mts	rmsr, r5
564	nop
565	lwi	r3, r1, PT_R3
566	lwi	r4, r1, PT_R4
567	lwi	r5, r1, PT_R5
568	lwi	r6, r1, PT_R6
569	lwi	r17, r1, PT_R17
570
571	rted	r17, 0
572	addik	r1, r1, (EX_HANDLER_STACK_SIZ); /* Restore stack frame */
573#else
574	RESTORE_STATE;
575	rted	r17, 0
576	nop
577#endif
578
579#ifdef CONFIG_MMU
580	/* Exception vector entry code. This code runs with address translation
581	 * turned off (i.e. using physical addresses). */
582
583	/* Exception vectors. */
584
585	/* 0x10 - Data Storage Exception
586	 * This happens for just a few reasons. U0 set (but we don't do that),
587	 * or zone protection fault (user violation, write to protected page).
588	 * If this is just an update of modified status, we do that quickly
589	 * and exit. Otherwise, we call heavyweight functions to do the work.
590	 */
591	handle_data_storage_exception:
592		/* Working registers already saved: R3, R4, R5, R6
593		 * R3 = ESR
594		 */
595		mfs	r11, rpid
596		nop
597		/* If we are faulting a kernel address, we have to use the
598		 * kernel page tables.
599		 */
600		ori	r5, r0, CONFIG_KERNEL_START
601		cmpu	r5, r3, r5
602		bgti	r5, ex3
603		/* First, check if it was a zone fault (which means a user
604		 * tried to access a kernel or read-protected page - always
605		 * a SEGV). All other faults here must be stores, so no
606		 * need to check ESR_S as well. */
607		andi	r4, r4, ESR_DIZ		/* ESR_Z - zone protection */
608		bnei	r4, ex2
609
610		ori	r4, r0, swapper_pg_dir
611		mts	rpid, r0		/* TLB will have 0 TID */
612		nop
613		bri	ex4
614
615		/* Get the PGD for the current thread. */
616	ex3:
617		/* First, check if it was a zone fault (which means a user
618		 * tried to access a kernel or read-protected page - always
619		 * a SEGV). All other faults here must be stores, so no
620		 * need to check ESR_S as well. */
621		andi	r4, r4, ESR_DIZ		/* ESR_Z */
622		bnei	r4, ex2
623		/* get current task address */
624		addi	r4 ,CURRENT_TASK, TOPHYS(0);
625		lwi	r4, r4, TASK_THREAD+PGDIR
626	ex4:
627		tophys(r4,r4)
628		/* Create L1 (pgdir/pmd) address */
629		bsrli	r5, r3, PGDIR_SHIFT - 2
630		andi	r5, r5, PAGE_SIZE - 4
631/* Assume pgdir aligned on 4K boundary, no need for "andi r4,r4,0xfffff003" */
632		or	r4, r4, r5
633		lwi	r4, r4, 0		/* Get L1 entry */
634		andi	r5, r4, PAGE_MASK /* Extract L2 (pte) base address */
635		beqi	r5, ex2			/* Bail if no table */
636
637		tophys(r5,r5)
638		bsrli	r6, r3, PTE_SHIFT /* Compute PTE address */
639		andi	r6, r6, PAGE_SIZE - 4
640		or	r5, r5, r6
641		lwi	r4, r5, 0		/* Get Linux PTE */
642
643		andi	r6, r4, _PAGE_RW	/* Is it writeable? */
644		beqi	r6, ex2			/* Bail if not */
645
646		/* Update 'changed' */
647		ori	r4, r4, _PAGE_DIRTY|_PAGE_ACCESSED|_PAGE_HWWRITE
648		swi	r4, r5, 0		/* Update Linux page table */
649
650		/* Most of the Linux PTE is ready to load into the TLB LO.
651		 * We set ZSEL, where only the LS-bit determines user access.
652		 * We set execute, because we don't have the granularity to
653		 * properly set this at the page level (Linux problem).
654		 * If shared is set, we cause a zero PID->TID load.
655		 * Many of these bits are software only. Bits we don't set
656		 * here we (properly should) assume have the appropriate value.
657		 */
658/* Ignore memory coherent, just LSB on ZSEL is used + EX/WR */
659		andi	r4, r4, PAGE_MASK | TLB_EX | TLB_WR | \
660						TLB_ZSEL(1) | TLB_ATTR_MASK
661		ori	r4, r4, _PAGE_HWEXEC	/* make it executable */
662
663		/* find the TLB index that caused the fault. It has to be here*/
664		mts	rtlbsx, r3
665		nop
666		mfs	r5, rtlbx		/* DEBUG: TBD */
667		nop
668		mts	rtlblo, r4		/* Load TLB LO */
669		nop
670						/* Will sync shadow TLBs */
671
672		/* Done...restore registers and get out of here. */
673		mts	rpid, r11
674		nop
675		bri 4
676
677		RESTORE_STATE;
678		rted	r17, 0
679		nop
680	ex2:
681		/* The bailout. Restore registers to pre-exception conditions
682		 * and call the heavyweights to help us out. */
683		mts	rpid, r11
684		nop
685		bri 4
686		RESTORE_STATE;
687		bri	page_fault_data_trap
688
689
690	/* 0x11 - Instruction Storage Exception
691	 * This is caused by a fetch from non-execute or guarded pages. */
692	handle_instruction_storage_exception:
693		/* Working registers already saved: R3, R4, R5, R6
694		 * R3 = ESR
695		 */
696
697		RESTORE_STATE;
698		bri	page_fault_instr_trap
699
700	/* 0x12 - Data TLB Miss Exception
701	 * As the name implies, translation is not in the MMU, so search the
702	 * page tables and fix it. The only purpose of this function is to
703	 * load TLB entries from the page table if they exist.
704	 */
705	handle_data_tlb_miss_exception:
706		/* Working registers already saved: R3, R4, R5, R6
707		 * R3 = EAR, R4 = ESR
708		 */
709		mfs	r11, rpid
710		nop
711
712		/* If we are faulting a kernel address, we have to use the
713		 * kernel page tables. */
714		ori	r6, r0, CONFIG_KERNEL_START
715		cmpu	r4, r3, r6
716		bgti	r4, ex5
717		ori	r4, r0, swapper_pg_dir
718		mts	rpid, r0		/* TLB will have 0 TID */
719		nop
720		bri	ex6
721
722		/* Get the PGD for the current thread. */
723	ex5:
724		/* get current task address */
725		addi	r4 ,CURRENT_TASK, TOPHYS(0);
726		lwi	r4, r4, TASK_THREAD+PGDIR
727	ex6:
728		tophys(r4,r4)
729		/* Create L1 (pgdir/pmd) address */
730		bsrli	r5, r3, PGDIR_SHIFT - 2
731		andi	r5, r5, PAGE_SIZE - 4
732/* Assume pgdir aligned on 4K boundary, no need for "andi r4,r4,0xfffff003" */
733		or	r4, r4, r5
734		lwi	r4, r4, 0		/* Get L1 entry */
735		andi	r5, r4, PAGE_MASK /* Extract L2 (pte) base address */
736		beqi	r5, ex7			/* Bail if no table */
737
738		tophys(r5,r5)
739		bsrli	r6, r3, PTE_SHIFT /* Compute PTE address */
740		andi	r6, r6, PAGE_SIZE - 4
741		or	r5, r5, r6
742		lwi	r4, r5, 0		/* Get Linux PTE */
743
744		andi	r6, r4, _PAGE_PRESENT
745		beqi	r6, ex7
746
747		ori	r4, r4, _PAGE_ACCESSED
748		swi	r4, r5, 0
749
750		/* Most of the Linux PTE is ready to load into the TLB LO.
751		 * We set ZSEL, where only the LS-bit determines user access.
752		 * We set execute, because we don't have the granularity to
753		 * properly set this at the page level (Linux problem).
754		 * If shared is set, we cause a zero PID->TID load.
755		 * Many of these bits are software only. Bits we don't set
756		 * here we (properly should) assume have the appropriate value.
757		 */
758		brid	finish_tlb_load
759		andi	r4, r4, PAGE_MASK | TLB_EX | TLB_WR | \
760						TLB_ZSEL(1) | TLB_ATTR_MASK
761	ex7:
762		/* The bailout. Restore registers to pre-exception conditions
763		 * and call the heavyweights to help us out.
764		 */
765		mts	rpid, r11
766		nop
767		bri	4
768		RESTORE_STATE;
769		bri	page_fault_data_trap
770
771	/* 0x13 - Instruction TLB Miss Exception
772	 * Nearly the same as above, except we get our information from
773	 * different registers and bailout to a different point.
774	 */
775	handle_instruction_tlb_miss_exception:
776		/* Working registers already saved: R3, R4, R5, R6
777		 *  R3 = ESR
778		 */
779		mfs	r11, rpid
780		nop
781
782		/* If we are faulting a kernel address, we have to use the
783		 * kernel page tables.
784		 */
785		ori	r4, r0, CONFIG_KERNEL_START
786		cmpu	r4, r3, r4
787		bgti	r4, ex8
788		ori	r4, r0, swapper_pg_dir
789		mts	rpid, r0		/* TLB will have 0 TID */
790		nop
791		bri	ex9
792
793		/* Get the PGD for the current thread. */
794	ex8:
795		/* get current task address */
796		addi	r4 ,CURRENT_TASK, TOPHYS(0);
797		lwi	r4, r4, TASK_THREAD+PGDIR
798	ex9:
799		tophys(r4,r4)
800		/* Create L1 (pgdir/pmd) address */
801		bsrli	r5, r3, PGDIR_SHIFT - 2
802		andi	r5, r5, PAGE_SIZE - 4
803/* Assume pgdir aligned on 4K boundary, no need for "andi r4,r4,0xfffff003" */
804		or	r4, r4, r5
805		lwi	r4, r4, 0		/* Get L1 entry */
806		andi	r5, r4, PAGE_MASK /* Extract L2 (pte) base address */
807		beqi	r5, ex10		/* Bail if no table */
808
809		tophys(r5,r5)
810		bsrli	r6, r3, PTE_SHIFT /* Compute PTE address */
811		andi	r6, r6, PAGE_SIZE - 4
812		or	r5, r5, r6
813		lwi	r4, r5, 0		/* Get Linux PTE */
814
815		andi	r6, r4, _PAGE_PRESENT
816		beqi	r6, ex10
817
818		ori	r4, r4, _PAGE_ACCESSED
819		swi	r4, r5, 0
820
821		/* Most of the Linux PTE is ready to load into the TLB LO.
822		 * We set ZSEL, where only the LS-bit determines user access.
823		 * We set execute, because we don't have the granularity to
824		 * properly set this at the page level (Linux problem).
825		 * If shared is set, we cause a zero PID->TID load.
826		 * Many of these bits are software only. Bits we don't set
827		 * here we (properly should) assume have the appropriate value.
828		 */
829		brid	finish_tlb_load
830		andi	r4, r4, PAGE_MASK | TLB_EX | TLB_WR | \
831						TLB_ZSEL(1) | TLB_ATTR_MASK
832	ex10:
833		/* The bailout. Restore registers to pre-exception conditions
834		 * and call the heavyweights to help us out.
835		 */
836		mts	rpid, r11
837		nop
838		bri 4
839		RESTORE_STATE;
840		bri	page_fault_instr_trap
841
842/* Both the instruction and data TLB miss get to this point to load the TLB.
843 *	r3 - EA of fault
844 *	r4 - TLB LO (info from Linux PTE)
845 *	r5, r6 - available to use
846 *	PID - loaded with proper value when we get here
847 *	Upon exit, we reload everything and RFI.
848 * A common place to load the TLB.
849 */
850.section .data
851.align 4
852.global tlb_skip
853	tlb_skip:
854		.long	MICROBLAZE_TLB_SKIP
855	tlb_index:
856		/* MS: storing last used tlb index */
857		.long	MICROBLAZE_TLB_SIZE/2
858.previous
859	finish_tlb_load:
860		/* MS: load the last used TLB index. */
861		lwi	r5, r0, TOPHYS(tlb_index)
862		addik	r5, r5, 1 /* MS: inc tlb_index -> use next one */
863
864/* MS: FIXME this is potential fault, because this is mask not count */
865		andi	r5, r5, MICROBLAZE_TLB_SIZE - 1
866		ori	r6, r0, 1
867		cmp	r31, r5, r6
868		blti	r31, ex12
869		lwi	r5, r0, TOPHYS(tlb_skip)
870	ex12:
871		/* MS: save back current TLB index */
872		swi	r5, r0, TOPHYS(tlb_index)
873
874		ori	r4, r4, _PAGE_HWEXEC	/* make it executable */
875		mts	rtlbx, r5		/* MS: save current TLB */
876		nop
877		mts	rtlblo,	r4		/* MS: save to TLB LO */
878		nop
879
880		/* Create EPN. This is the faulting address plus a static
881		 * set of bits. These are size, valid, E, U0, and ensure
882		 * bits 20 and 21 are zero.
883		 */
884		andi	r3, r3, PAGE_MASK
885#ifdef CONFIG_MICROBLAZE_64K_PAGES
886		ori	r3, r3, TLB_VALID | TLB_PAGESZ(PAGESZ_64K)
887#elif CONFIG_MICROBLAZE_16K_PAGES
888		ori	r3, r3, TLB_VALID | TLB_PAGESZ(PAGESZ_16K)
889#else
890		ori	r3, r3, TLB_VALID | TLB_PAGESZ(PAGESZ_4K)
891#endif
892		mts	rtlbhi,	r3		/* Load TLB HI */
893		nop
894
895		/* Done...restore registers and get out of here. */
896		mts	rpid, r11
897		nop
898		bri 4
899		RESTORE_STATE;
900		rted	r17, 0
901		nop
902
903	/* extern void giveup_fpu(struct task_struct *prev)
904	 *
905	 * The MicroBlaze processor may have an FPU, so this should not just
906	 * return: TBD.
907	 */
908	.globl giveup_fpu;
909	.align 4;
910	giveup_fpu:
911		bralid	r15,0			/* TBD */
912		nop
913
914	/* At present, this routine just hangs. - extern void abort(void) */
915	.globl abort;
916	.align 4;
917	abort:
918		br	r0
919
920	.globl set_context;
921	.align 4;
922	set_context:
923		mts	rpid, r5	/* Shadow TLBs are automatically */
924		nop
925		bri	4		/* flushed by changing PID */
926		rtsd	r15,8
927		nop
928
929#endif
930.end _hw_exception_handler
931
932#ifdef CONFIG_MMU
933/* Unaligned data access exception last on a 4k page for MMU.
934 * When this is called, we are in virtual mode with exceptions enabled
935 * and registers 1-13,15,17,18 saved.
936 *
937 * R3 = ESR
938 * R4 = EAR
939 * R7 = pointer to saved registers (struct pt_regs *regs)
940 *
941 * This handler perform the access, and returns via ret_from_exc.
942 */
943.global _unaligned_data_exception
944.ent _unaligned_data_exception
945_unaligned_data_exception:
946	andi	r8, r3, 0x3E0;	/* Mask and extract the register operand */
947	bsrli   r8, r8, 2;		/* r8 >> 2 = register operand * 8 */
948	andi	r6, r3, 0x400;	/* Extract ESR[S] */
949	bneid	r6, ex_sw_vm;
950	andi	r6, r3, 0x800;	/* Extract ESR[W] - delay slot */
951ex_lw_vm:
952	beqid	r6, ex_lhw_vm;
953load1:	lbui	r5, r4, 0;	/* Exception address in r4 - delay slot */
954/* Load a word, byte-by-byte from destination address and save it in tmp space*/
955	addik	r6, r0, ex_tmp_data_loc_0;
956	sbi	r5, r6, 0;
957load2:	lbui	r5, r4, 1;
958	sbi	r5, r6, 1;
959load3:	lbui	r5, r4, 2;
960	sbi	r5, r6, 2;
961load4:	lbui	r5, r4, 3;
962	sbi	r5, r6, 3;
963	brid	ex_lw_tail_vm;
964/* Get the destination register value into r3 - delay slot */
965	lwi	r3, r6, 0;
966ex_lhw_vm:
967	/* Load a half-word, byte-by-byte from destination address and
968	 * save it in tmp space */
969	addik	r6, r0, ex_tmp_data_loc_0;
970	sbi	r5, r6, 0;
971load5:	lbui	r5, r4, 1;
972	sbi	r5, r6, 1;
973	lhui	r3, r6, 0;	/* Get the destination register value into r3 */
974ex_lw_tail_vm:
975	/* Form load_word jump table offset (lw_table_vm + (8 * regnum)) */
976	addik	r5, r8, lw_table_vm;
977	bra	r5;
978ex_lw_end_vm:			/* Exception handling of load word, ends */
979	brai	ret_from_exc;
980ex_sw_vm:
981/* Form store_word jump table offset (sw_table_vm + (8 * regnum)) */
982	addik	r5, r8, sw_table_vm;
983	bra	r5;
984ex_sw_tail_vm:
985	addik	r5, r0, ex_tmp_data_loc_0;
986	beqid	r6, ex_shw_vm;
987	swi	r3, r5, 0;	/* Get the word - delay slot */
988	/* Store the word, byte-by-byte into destination address */
989	lbui	r3, r5, 0;
990store1:	sbi	r3, r4, 0;
991	lbui	r3, r5, 1;
992store2:	sbi	r3, r4, 1;
993	lbui	r3, r5, 2;
994store3:	sbi	r3, r4, 2;
995	lbui	r3, r5, 3;
996	brid	ret_from_exc;
997store4:	sbi	r3, r4, 3;	/* Delay slot */
998ex_shw_vm:
999	/* Store the lower half-word, byte-by-byte into destination address */
1000#ifdef __MICROBLAZEEL__
1001	lbui	r3, r5, 0;
1002store5:	sbi	r3, r4, 0;
1003	lbui	r3, r5, 1;
1004	brid	ret_from_exc;
1005store6:	sbi	r3, r4, 1;	/* Delay slot */
1006#else
1007	lbui	r3, r5, 2;
1008store5:	sbi	r3, r4, 0;
1009	lbui	r3, r5, 3;
1010	brid	ret_from_exc;
1011store6:	sbi	r3, r4, 1;	/* Delay slot */
1012#endif
1013
1014ex_sw_end_vm:			/* Exception handling of store word, ends. */
1015
1016/* We have to prevent cases that get/put_user macros get unaligned pointer
1017 * to bad page area. We have to find out which origin instruction caused it
1018 * and called fixup for that origin instruction not instruction in unaligned
1019 * handler */
1020ex_unaligned_fixup:
1021	ori	r5, r7, 0 /* setup pointer to pt_regs */
1022	lwi	r6, r7, PT_PC; /* faulting address is one instruction above */
1023	addik	r6, r6, -4 /* for finding proper fixup */
1024	swi	r6, r7, PT_PC; /* a save back it to PT_PC */
1025	addik	r7, r0, SIGSEGV
1026	/* call bad_page_fault for finding aligned fixup, fixup address is saved
1027	 * in PT_PC which is used as return address from exception */
1028	addik	r15, r0, ret_from_exc-8 /* setup return address */
1029	brid	bad_page_fault
1030	nop
1031
1032/* We prevent all load/store because it could failed any attempt to access */
1033.section __ex_table,"a";
1034	.word	load1,ex_unaligned_fixup;
1035	.word	load2,ex_unaligned_fixup;
1036	.word	load3,ex_unaligned_fixup;
1037	.word	load4,ex_unaligned_fixup;
1038	.word	load5,ex_unaligned_fixup;
1039	.word	store1,ex_unaligned_fixup;
1040	.word	store2,ex_unaligned_fixup;
1041	.word	store3,ex_unaligned_fixup;
1042	.word	store4,ex_unaligned_fixup;
1043	.word	store5,ex_unaligned_fixup;
1044	.word	store6,ex_unaligned_fixup;
1045.previous;
1046.end _unaligned_data_exception
1047#endif /* CONFIG_MMU */
1048
1049.global ex_handler_unhandled
1050ex_handler_unhandled:
1051/* FIXME add handle function for unhandled exception - dump register */
1052	bri 0
1053
1054/*
1055 * hw_exception_handler Jump Table
1056 * - Contains code snippets for each register that caused the unalign exception
1057 * - Hence exception handler is NOT self-modifying
1058 * - Separate table for load exceptions and store exceptions.
1059 * - Each table is of size: (8 * 32) = 256 bytes
1060 */
1061
1062.section .text
1063.align 4
1064lw_table:
1065lw_r0:		R3_TO_LWREG	(0);
1066lw_r1:		LWREG_NOP;
1067lw_r2:		R3_TO_LWREG	(2);
1068lw_r3:		R3_TO_LWREG_V	(3);
1069lw_r4:		R3_TO_LWREG_V	(4);
1070lw_r5:		R3_TO_LWREG_V	(5);
1071lw_r6:		R3_TO_LWREG_V	(6);
1072lw_r7:		R3_TO_LWREG	(7);
1073lw_r8:		R3_TO_LWREG	(8);
1074lw_r9:		R3_TO_LWREG	(9);
1075lw_r10:		R3_TO_LWREG	(10);
1076lw_r11:		R3_TO_LWREG	(11);
1077lw_r12:		R3_TO_LWREG	(12);
1078lw_r13:		R3_TO_LWREG	(13);
1079lw_r14:		R3_TO_LWREG	(14);
1080lw_r15:		R3_TO_LWREG	(15);
1081lw_r16:		R3_TO_LWREG	(16);
1082lw_r17:		LWREG_NOP;
1083lw_r18:		R3_TO_LWREG	(18);
1084lw_r19:		R3_TO_LWREG	(19);
1085lw_r20:		R3_TO_LWREG	(20);
1086lw_r21:		R3_TO_LWREG	(21);
1087lw_r22:		R3_TO_LWREG	(22);
1088lw_r23:		R3_TO_LWREG	(23);
1089lw_r24:		R3_TO_LWREG	(24);
1090lw_r25:		R3_TO_LWREG	(25);
1091lw_r26:		R3_TO_LWREG	(26);
1092lw_r27:		R3_TO_LWREG	(27);
1093lw_r28:		R3_TO_LWREG	(28);
1094lw_r29:		R3_TO_LWREG	(29);
1095lw_r30:		R3_TO_LWREG	(30);
1096#ifdef CONFIG_MMU
1097lw_r31: 	R3_TO_LWREG_V	(31);
1098#else
1099lw_r31:		R3_TO_LWREG	(31);
1100#endif
1101
1102sw_table:
1103sw_r0:		SWREG_TO_R3	(0);
1104sw_r1:		SWREG_NOP;
1105sw_r2:		SWREG_TO_R3	(2);
1106sw_r3:		SWREG_TO_R3_V	(3);
1107sw_r4:		SWREG_TO_R3_V	(4);
1108sw_r5:		SWREG_TO_R3_V	(5);
1109sw_r6:		SWREG_TO_R3_V	(6);
1110sw_r7:		SWREG_TO_R3	(7);
1111sw_r8:		SWREG_TO_R3	(8);
1112sw_r9:		SWREG_TO_R3	(9);
1113sw_r10:		SWREG_TO_R3	(10);
1114sw_r11:		SWREG_TO_R3	(11);
1115sw_r12:		SWREG_TO_R3	(12);
1116sw_r13:		SWREG_TO_R3	(13);
1117sw_r14:		SWREG_TO_R3	(14);
1118sw_r15:		SWREG_TO_R3	(15);
1119sw_r16:		SWREG_TO_R3	(16);
1120sw_r17:		SWREG_NOP;
1121sw_r18:		SWREG_TO_R3	(18);
1122sw_r19:		SWREG_TO_R3	(19);
1123sw_r20:		SWREG_TO_R3	(20);
1124sw_r21:		SWREG_TO_R3	(21);
1125sw_r22:		SWREG_TO_R3	(22);
1126sw_r23:		SWREG_TO_R3	(23);
1127sw_r24:		SWREG_TO_R3	(24);
1128sw_r25:		SWREG_TO_R3	(25);
1129sw_r26:		SWREG_TO_R3	(26);
1130sw_r27:		SWREG_TO_R3	(27);
1131sw_r28:		SWREG_TO_R3	(28);
1132sw_r29:		SWREG_TO_R3	(29);
1133sw_r30:		SWREG_TO_R3	(30);
1134#ifdef CONFIG_MMU
1135sw_r31:		SWREG_TO_R3_V	(31);
1136#else
1137sw_r31:		SWREG_TO_R3	(31);
1138#endif
1139
1140#ifdef CONFIG_MMU
1141lw_table_vm:
1142lw_r0_vm:	R3_TO_LWREG_VM		(0);
1143lw_r1_vm:	R3_TO_LWREG_VM_V	(1);
1144lw_r2_vm:	R3_TO_LWREG_VM_V	(2);
1145lw_r3_vm:	R3_TO_LWREG_VM_V	(3);
1146lw_r4_vm:	R3_TO_LWREG_VM_V	(4);
1147lw_r5_vm:	R3_TO_LWREG_VM_V	(5);
1148lw_r6_vm:	R3_TO_LWREG_VM_V	(6);
1149lw_r7_vm:	R3_TO_LWREG_VM_V	(7);
1150lw_r8_vm:	R3_TO_LWREG_VM_V	(8);
1151lw_r9_vm:	R3_TO_LWREG_VM_V	(9);
1152lw_r10_vm:	R3_TO_LWREG_VM_V	(10);
1153lw_r11_vm:	R3_TO_LWREG_VM_V	(11);
1154lw_r12_vm:	R3_TO_LWREG_VM_V	(12);
1155lw_r13_vm:	R3_TO_LWREG_VM_V	(13);
1156lw_r14_vm:	R3_TO_LWREG_VM_V	(14);
1157lw_r15_vm:	R3_TO_LWREG_VM_V	(15);
1158lw_r16_vm:	R3_TO_LWREG_VM_V	(16);
1159lw_r17_vm:	R3_TO_LWREG_VM_V	(17);
1160lw_r18_vm:	R3_TO_LWREG_VM_V	(18);
1161lw_r19_vm:	R3_TO_LWREG_VM_V	(19);
1162lw_r20_vm:	R3_TO_LWREG_VM_V	(20);
1163lw_r21_vm:	R3_TO_LWREG_VM_V	(21);
1164lw_r22_vm:	R3_TO_LWREG_VM_V	(22);
1165lw_r23_vm:	R3_TO_LWREG_VM_V	(23);
1166lw_r24_vm:	R3_TO_LWREG_VM_V	(24);
1167lw_r25_vm:	R3_TO_LWREG_VM_V	(25);
1168lw_r26_vm:	R3_TO_LWREG_VM_V	(26);
1169lw_r27_vm:	R3_TO_LWREG_VM_V	(27);
1170lw_r28_vm:	R3_TO_LWREG_VM_V	(28);
1171lw_r29_vm:	R3_TO_LWREG_VM_V	(29);
1172lw_r30_vm:	R3_TO_LWREG_VM_V	(30);
1173lw_r31_vm:	R3_TO_LWREG_VM_V	(31);
1174
1175sw_table_vm:
1176sw_r0_vm:	SWREG_TO_R3_VM		(0);
1177sw_r1_vm:	SWREG_TO_R3_VM_V	(1);
1178sw_r2_vm:	SWREG_TO_R3_VM_V	(2);
1179sw_r3_vm:	SWREG_TO_R3_VM_V	(3);
1180sw_r4_vm:	SWREG_TO_R3_VM_V	(4);
1181sw_r5_vm:	SWREG_TO_R3_VM_V	(5);
1182sw_r6_vm:	SWREG_TO_R3_VM_V	(6);
1183sw_r7_vm:	SWREG_TO_R3_VM_V	(7);
1184sw_r8_vm:	SWREG_TO_R3_VM_V	(8);
1185sw_r9_vm:	SWREG_TO_R3_VM_V	(9);
1186sw_r10_vm:	SWREG_TO_R3_VM_V	(10);
1187sw_r11_vm:	SWREG_TO_R3_VM_V	(11);
1188sw_r12_vm:	SWREG_TO_R3_VM_V	(12);
1189sw_r13_vm:	SWREG_TO_R3_VM_V	(13);
1190sw_r14_vm:	SWREG_TO_R3_VM_V	(14);
1191sw_r15_vm:	SWREG_TO_R3_VM_V	(15);
1192sw_r16_vm:	SWREG_TO_R3_VM_V	(16);
1193sw_r17_vm:	SWREG_TO_R3_VM_V	(17);
1194sw_r18_vm:	SWREG_TO_R3_VM_V	(18);
1195sw_r19_vm:	SWREG_TO_R3_VM_V	(19);
1196sw_r20_vm:	SWREG_TO_R3_VM_V	(20);
1197sw_r21_vm:	SWREG_TO_R3_VM_V	(21);
1198sw_r22_vm:	SWREG_TO_R3_VM_V	(22);
1199sw_r23_vm:	SWREG_TO_R3_VM_V	(23);
1200sw_r24_vm:	SWREG_TO_R3_VM_V	(24);
1201sw_r25_vm:	SWREG_TO_R3_VM_V	(25);
1202sw_r26_vm:	SWREG_TO_R3_VM_V	(26);
1203sw_r27_vm:	SWREG_TO_R3_VM_V	(27);
1204sw_r28_vm:	SWREG_TO_R3_VM_V	(28);
1205sw_r29_vm:	SWREG_TO_R3_VM_V	(29);
1206sw_r30_vm:	SWREG_TO_R3_VM_V	(30);
1207sw_r31_vm:	SWREG_TO_R3_VM_V	(31);
1208#endif /* CONFIG_MMU */
1209
1210/* Temporary data structures used in the handler */
1211.section .data
1212.align 4
1213ex_tmp_data_loc_0:
1214	.byte 0
1215ex_tmp_data_loc_1:
1216	.byte 0
1217ex_tmp_data_loc_2:
1218	.byte 0
1219ex_tmp_data_loc_3:
1220	.byte 0
1221ex_reg_op:
1222	.byte 0
1223