xref: /openbmc/linux/arch/parisc/kernel/entry.S (revision 6197e5b7)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
4 *
5 * kernel entry points (interruptions, system call wrappers)
6 *  Copyright (C) 1999,2000 Philipp Rumpf
7 *  Copyright (C) 1999 SuSE GmbH Nuernberg
8 *  Copyright (C) 2000 Hewlett-Packard (John Marvin)
9 *  Copyright (C) 1999 Hewlett-Packard (Frank Rowand)
10 */
11
12#include <asm/asm-offsets.h>
13
14/* we have the following possibilities to act on an interruption:
15 *  - handle in assembly and use shadowed registers only
16 *  - save registers to kernel stack and handle in assembly or C */
17
18
19#include <asm/psw.h>
20#include <asm/cache.h>		/* for L1_CACHE_SHIFT */
21#include <asm/assembly.h>	/* for LDREG/STREG defines */
22#include <asm/signal.h>
23#include <asm/unistd.h>
24#include <asm/ldcw.h>
25#include <asm/traps.h>
26#include <asm/thread_info.h>
27#include <asm/alternative.h>
28
29#include <linux/linkage.h>
30#include <linux/pgtable.h>
31
32#ifdef CONFIG_64BIT
33	.level 2.0w
34#else
35	.level 2.0
36#endif
37
38	.import		pa_tlb_lock,data
39	.macro  load_pa_tlb_lock reg
40	mfctl		%cr25,\reg
41	addil		L%(PAGE_SIZE << (PGD_ALLOC_ORDER - 1)),\reg
42	.endm
43
44	/* space_to_prot macro creates a prot id from a space id */
45
46#if (SPACEID_SHIFT) == 0
47	.macro  space_to_prot spc prot
48	depd,z  \spc,62,31,\prot
49	.endm
50#else
51	.macro  space_to_prot spc prot
52	extrd,u \spc,(64 - (SPACEID_SHIFT)),32,\prot
53	.endm
54#endif
55
56	/* Switch to virtual mapping, trashing only %r1 */
57	.macro  virt_map
58	/* pcxt_ssm_bug */
59	rsm	PSW_SM_I, %r0	/* barrier for "Relied upon Translation */
60	mtsp	%r0, %sr4
61	mtsp	%r0, %sr5
62	mtsp	%r0, %sr6
63	tovirt_r1 %r29
64	load32	KERNEL_PSW, %r1
65
66	rsm     PSW_SM_QUIET,%r0	/* second "heavy weight" ctl op */
67	mtctl	%r0, %cr17	/* Clear IIASQ tail */
68	mtctl	%r0, %cr17	/* Clear IIASQ head */
69	mtctl	%r1, %ipsw
70	load32	4f, %r1
71	mtctl	%r1, %cr18	/* Set IIAOQ tail */
72	ldo	4(%r1), %r1
73	mtctl	%r1, %cr18	/* Set IIAOQ head */
74	rfir
75	nop
764:
77	.endm
78
79	/*
80	 * The "get_stack" macros are responsible for determining the
81	 * kernel stack value.
82	 *
83	 *      If sr7 == 0
84	 *          Already using a kernel stack, so call the
85	 *          get_stack_use_r30 macro to push a pt_regs structure
86	 *          on the stack, and store registers there.
87	 *      else
88	 *          Need to set up a kernel stack, so call the
89	 *          get_stack_use_cr30 macro to set up a pointer
90	 *          to the pt_regs structure contained within the
91	 *          task pointer pointed to by cr30. Set the stack
92	 *          pointer to point to the end of the task structure.
93	 *
94	 * Note that we use shadowed registers for temps until
95	 * we can save %r26 and %r29. %r26 is used to preserve
96	 * %r8 (a shadowed register) which temporarily contained
97	 * either the fault type ("code") or the eirr. We need
98	 * to use a non-shadowed register to carry the value over
99	 * the rfir in virt_map. We use %r26 since this value winds
100	 * up being passed as the argument to either do_cpu_irq_mask
101	 * or handle_interruption. %r29 is used to hold a pointer
102	 * the register save area, and once again, it needs to
103	 * be a non-shadowed register so that it survives the rfir.
104	 *
105	 * N.B. TASK_SZ_ALGN and PT_SZ_ALGN include space for a stack frame.
106	 */
107
108	.macro  get_stack_use_cr30
109
110	/* we save the registers in the task struct */
111
112	copy	%r30, %r17
113	mfctl   %cr30, %r1
114	ldo	THREAD_SZ_ALGN(%r1), %r30
115	mtsp	%r0,%sr7
116	mtsp	%r16,%sr3
117	tophys  %r1,%r9
118	LDREG	TI_TASK(%r9), %r1	/* thread_info -> task_struct */
119	tophys  %r1,%r9
120	ldo     TASK_REGS(%r9),%r9
121	STREG   %r17,PT_GR30(%r9)
122	STREG   %r29,PT_GR29(%r9)
123	STREG   %r26,PT_GR26(%r9)
124	STREG	%r16,PT_SR7(%r9)
125	copy    %r9,%r29
126	.endm
127
128	.macro  get_stack_use_r30
129
130	/* we put a struct pt_regs on the stack and save the registers there */
131
132	tophys  %r30,%r9
133	copy	%r30,%r1
134	ldo	PT_SZ_ALGN(%r30),%r30
135	STREG   %r1,PT_GR30(%r9)
136	STREG   %r29,PT_GR29(%r9)
137	STREG   %r26,PT_GR26(%r9)
138	STREG	%r16,PT_SR7(%r9)
139	copy    %r9,%r29
140	.endm
141
142	.macro  rest_stack
143	LDREG   PT_GR1(%r29), %r1
144	LDREG   PT_GR30(%r29),%r30
145	LDREG   PT_GR29(%r29),%r29
146	.endm
147
148	/* default interruption handler
149	 * (calls traps.c:handle_interruption) */
150	.macro	def code
151	b	intr_save
152	ldi     \code, %r8
153	.align	32
154	.endm
155
156	/* Interrupt interruption handler
157	 * (calls irq.c:do_cpu_irq_mask) */
158	.macro	extint code
159	b	intr_extint
160	mfsp    %sr7,%r16
161	.align	32
162	.endm
163
164	.import	os_hpmc, code
165
166	/* HPMC handler */
167	.macro	hpmc code
168	nop			/* must be a NOP, will be patched later */
169	load32	PA(os_hpmc), %r3
170	bv,n	0(%r3)
171	nop
172	.word	0		/* checksum (will be patched) */
173	.word	0		/* address of handler */
174	.word	0		/* length of handler */
175	.endm
176
177	/*
178	 * Performance Note: Instructions will be moved up into
179	 * this part of the code later on, once we are sure
180	 * that the tlb miss handlers are close to final form.
181	 */
182
183	/* Register definitions for tlb miss handler macros */
184
185	va  = r8	/* virtual address for which the trap occurred */
186	spc = r24	/* space for which the trap occurred */
187
188#ifndef CONFIG_64BIT
189
190	/*
191	 * itlb miss interruption handler (parisc 1.1 - 32 bit)
192	 */
193
194	.macro	itlb_11 code
195
196	mfctl	%pcsq, spc
197	b	itlb_miss_11
198	mfctl	%pcoq, va
199
200	.align		32
201	.endm
202#endif
203
204	/*
205	 * itlb miss interruption handler (parisc 2.0)
206	 */
207
208	.macro	itlb_20 code
209	mfctl	%pcsq, spc
210#ifdef CONFIG_64BIT
211	b       itlb_miss_20w
212#else
213	b	itlb_miss_20
214#endif
215	mfctl	%pcoq, va
216
217	.align		32
218	.endm
219
220#ifndef CONFIG_64BIT
221	/*
222	 * naitlb miss interruption handler (parisc 1.1 - 32 bit)
223	 */
224
225	.macro	naitlb_11 code
226
227	mfctl	%isr,spc
228	b	naitlb_miss_11
229	mfctl 	%ior,va
230
231	.align		32
232	.endm
233#endif
234
235	/*
236	 * naitlb miss interruption handler (parisc 2.0)
237	 */
238
239	.macro	naitlb_20 code
240
241	mfctl	%isr,spc
242#ifdef CONFIG_64BIT
243	b       naitlb_miss_20w
244#else
245	b	naitlb_miss_20
246#endif
247	mfctl 	%ior,va
248
249	.align		32
250	.endm
251
252#ifndef CONFIG_64BIT
253	/*
254	 * dtlb miss interruption handler (parisc 1.1 - 32 bit)
255	 */
256
257	.macro	dtlb_11 code
258
259	mfctl	%isr, spc
260	b	dtlb_miss_11
261	mfctl	%ior, va
262
263	.align		32
264	.endm
265#endif
266
267	/*
268	 * dtlb miss interruption handler (parisc 2.0)
269	 */
270
271	.macro	dtlb_20 code
272
273	mfctl	%isr, spc
274#ifdef CONFIG_64BIT
275	b       dtlb_miss_20w
276#else
277	b	dtlb_miss_20
278#endif
279	mfctl	%ior, va
280
281	.align		32
282	.endm
283
284#ifndef CONFIG_64BIT
285	/* nadtlb miss interruption handler (parisc 1.1 - 32 bit) */
286
287	.macro	nadtlb_11 code
288
289	mfctl	%isr,spc
290	b       nadtlb_miss_11
291	mfctl	%ior,va
292
293	.align		32
294	.endm
295#endif
296
297	/* nadtlb miss interruption handler (parisc 2.0) */
298
299	.macro	nadtlb_20 code
300
301	mfctl	%isr,spc
302#ifdef CONFIG_64BIT
303	b       nadtlb_miss_20w
304#else
305	b       nadtlb_miss_20
306#endif
307	mfctl	%ior,va
308
309	.align		32
310	.endm
311
312#ifndef CONFIG_64BIT
313	/*
314	 * dirty bit trap interruption handler (parisc 1.1 - 32 bit)
315	 */
316
317	.macro	dbit_11 code
318
319	mfctl	%isr,spc
320	b	dbit_trap_11
321	mfctl	%ior,va
322
323	.align		32
324	.endm
325#endif
326
327	/*
328	 * dirty bit trap interruption handler (parisc 2.0)
329	 */
330
331	.macro	dbit_20 code
332
333	mfctl	%isr,spc
334#ifdef CONFIG_64BIT
335	b       dbit_trap_20w
336#else
337	b	dbit_trap_20
338#endif
339	mfctl	%ior,va
340
341	.align		32
342	.endm
343
344	/* In LP64, the space contains part of the upper 32 bits of the
345	 * fault.  We have to extract this and place it in the va,
346	 * zeroing the corresponding bits in the space register */
347	.macro		space_adjust	spc,va,tmp
348#ifdef CONFIG_64BIT
349	extrd,u		\spc,63,SPACEID_SHIFT,\tmp
350	depd		%r0,63,SPACEID_SHIFT,\spc
351	depd		\tmp,31,SPACEID_SHIFT,\va
352#endif
353	.endm
354
355	.import		swapper_pg_dir,code
356
357	/* Get the pgd.  For faults on space zero (kernel space), this
358	 * is simply swapper_pg_dir.  For user space faults, the
359	 * pgd is stored in %cr25 */
360	.macro		get_pgd		spc,reg
361	ldil		L%PA(swapper_pg_dir),\reg
362	ldo		R%PA(swapper_pg_dir)(\reg),\reg
363	or,COND(=)	%r0,\spc,%r0
364	mfctl		%cr25,\reg
365	.endm
366
367	/*
368		space_check(spc,tmp,fault)
369
370		spc - The space we saw the fault with.
371		tmp - The place to store the current space.
372		fault - Function to call on failure.
373
374		Only allow faults on different spaces from the
375		currently active one if we're the kernel
376
377	*/
378	.macro		space_check	spc,tmp,fault
379	mfsp		%sr7,\tmp
380	/* check against %r0 which is same value as LINUX_GATEWAY_SPACE */
381	or,COND(<>)	%r0,\spc,%r0	/* user may execute gateway page
382					 * as kernel, so defeat the space
383					 * check if it is */
384	copy		\spc,\tmp
385	or,COND(=)	%r0,\tmp,%r0	/* nullify if executing as kernel */
386	cmpb,COND(<>),n	\tmp,\spc,\fault
387	.endm
388
389	/* Look up a PTE in a 2-Level scheme (faulting at each
390	 * level if the entry isn't present
391	 *
392	 * NOTE: we use ldw even for LP64, since the short pointers
393	 * can address up to 1TB
394	 */
395	.macro		L2_ptep	pmd,pte,index,va,fault
396#if CONFIG_PGTABLE_LEVELS == 3
397	extru		\va,31-ASM_PMD_SHIFT,ASM_BITS_PER_PMD,\index
398#else
399# if defined(CONFIG_64BIT)
400	extrd,u		\va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
401  #else
402  # if PAGE_SIZE > 4096
403	extru		\va,31-ASM_PGDIR_SHIFT,32-ASM_PGDIR_SHIFT,\index
404  # else
405	extru		\va,31-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
406  # endif
407# endif
408#endif
409	dep             %r0,31,PAGE_SHIFT,\pmd  /* clear offset */
410	copy		%r0,\pte
411	ldw,s		\index(\pmd),\pmd
412	bb,>=,n		\pmd,_PxD_PRESENT_BIT,\fault
413	dep		%r0,31,PxD_FLAG_SHIFT,\pmd /* clear flags */
414	SHLREG		\pmd,PxD_VALUE_SHIFT,\pmd
415	extru		\va,31-PAGE_SHIFT,ASM_BITS_PER_PTE,\index
416	dep		%r0,31,PAGE_SHIFT,\pmd  /* clear offset */
417	shladd		\index,BITS_PER_PTE_ENTRY,\pmd,\pmd /* pmd is now pte */
418	.endm
419
420	/* Look up PTE in a 3-Level scheme.
421	 *
422	 * Here we implement a Hybrid L2/L3 scheme: we allocate the
423	 * first pmd adjacent to the pgd.  This means that we can
424	 * subtract a constant offset to get to it.  The pmd and pgd
425	 * sizes are arranged so that a single pmd covers 4GB (giving
426	 * a full LP64 process access to 8TB) so our lookups are
427	 * effectively L2 for the first 4GB of the kernel (i.e. for
428	 * all ILP32 processes and all the kernel for machines with
429	 * under 4GB of memory) */
430	.macro		L3_ptep pgd,pte,index,va,fault
431#if CONFIG_PGTABLE_LEVELS == 3 /* we might have a 2-Level scheme, e.g. with 16kb page size */
432	extrd,u		\va,63-ASM_PGDIR_SHIFT,ASM_BITS_PER_PGD,\index
433	extrd,u,*=	\va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
434	ldw,s		\index(\pgd),\pgd
435	extrd,u,*=	\va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
436	bb,>=,n		\pgd,_PxD_PRESENT_BIT,\fault
437	extrd,u,*=	\va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
438	shld		\pgd,PxD_VALUE_SHIFT,\index
439	extrd,u,*=	\va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
440	copy		\index,\pgd
441	extrd,u,*<>	\va,63-ASM_PGDIR_SHIFT,64-ASM_PGDIR_SHIFT,%r0
442	ldo		ASM_PGD_PMD_OFFSET(\pgd),\pgd
443#endif
444	L2_ptep		\pgd,\pte,\index,\va,\fault
445	.endm
446
447	/* Acquire pa_tlb_lock lock and check page is present. */
448	.macro		tlb_lock	spc,ptp,pte,tmp,tmp1,fault
449#ifdef CONFIG_SMP
45098:	cmpib,COND(=),n	0,\spc,2f
451	load_pa_tlb_lock \tmp
4521:	LDCW		0(\tmp),\tmp1
453	cmpib,COND(=)	0,\tmp1,1b
454	nop
455	LDREG		0(\ptp),\pte
456	bb,<,n		\pte,_PAGE_PRESENT_BIT,3f
457	b		\fault
458	stw		\spc,0(\tmp)
45999:	ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
460#endif
4612:	LDREG		0(\ptp),\pte
462	bb,>=,n		\pte,_PAGE_PRESENT_BIT,\fault
4633:
464	.endm
465
466	/* Release pa_tlb_lock lock without reloading lock address.
467	   Note that the values in the register spc are limited to
468	   NR_SPACE_IDS (262144). Thus, the stw instruction always
469	   stores a nonzero value even when register spc is 64 bits.
470	   We use an ordered store to ensure all prior accesses are
471	   performed prior to releasing the lock. */
472	.macro		tlb_unlock0	spc,tmp
473#ifdef CONFIG_SMP
47498:	or,COND(=)	%r0,\spc,%r0
475	stw,ma		\spc,0(\tmp)
47699:	ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
477#endif
478	.endm
479
480	/* Release pa_tlb_lock lock. */
481	.macro		tlb_unlock1	spc,tmp
482#ifdef CONFIG_SMP
48398:	load_pa_tlb_lock \tmp
48499:	ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
485	tlb_unlock0	\spc,\tmp
486#endif
487	.endm
488
489	/* Set the _PAGE_ACCESSED bit of the PTE.  Be clever and
490	 * don't needlessly dirty the cache line if it was already set */
491	.macro		update_accessed	ptp,pte,tmp,tmp1
492	ldi		_PAGE_ACCESSED,\tmp1
493	or		\tmp1,\pte,\tmp
494	and,COND(<>)	\tmp1,\pte,%r0
495	STREG		\tmp,0(\ptp)
496	.endm
497
498	/* Set the dirty bit (and accessed bit).  No need to be
499	 * clever, this is only used from the dirty fault */
500	.macro		update_dirty	ptp,pte,tmp
501	ldi		_PAGE_ACCESSED|_PAGE_DIRTY,\tmp
502	or		\tmp,\pte,\pte
503	STREG		\pte,0(\ptp)
504	.endm
505
506	/* We have (depending on the page size):
507	 * - 38 to 52-bit Physical Page Number
508	 * - 12 to 26-bit page offset
509	 */
510	/* bitshift difference between a PFN (based on kernel's PAGE_SIZE)
511	 * to a CPU TLB 4k PFN (4k => 12 bits to shift) */
512	#define PAGE_ADD_SHIFT		(PAGE_SHIFT-12)
513	#define PAGE_ADD_HUGE_SHIFT	(REAL_HPAGE_SHIFT-12)
514
515	/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
516	.macro		convert_for_tlb_insert20 pte,tmp
517#ifdef CONFIG_HUGETLB_PAGE
518	copy		\pte,\tmp
519	extrd,u		\tmp,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
520				64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
521
522	depdi		_PAGE_SIZE_ENCODING_DEFAULT,63,\
523				(63-58)+PAGE_ADD_SHIFT,\pte
524	extrd,u,*=	\tmp,_PAGE_HPAGE_BIT+32,1,%r0
525	depdi		_HUGE_PAGE_SIZE_ENCODING_DEFAULT,63,\
526				(63-58)+PAGE_ADD_HUGE_SHIFT,\pte
527#else /* Huge pages disabled */
528	extrd,u		\pte,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
529				64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
530	depdi		_PAGE_SIZE_ENCODING_DEFAULT,63,\
531				(63-58)+PAGE_ADD_SHIFT,\pte
532#endif
533	.endm
534
535	/* Convert the pte and prot to tlb insertion values.  How
536	 * this happens is quite subtle, read below */
537	.macro		make_insert_tlb	spc,pte,prot,tmp
538	space_to_prot   \spc \prot        /* create prot id from space */
539	/* The following is the real subtlety.  This is depositing
540	 * T <-> _PAGE_REFTRAP
541	 * D <-> _PAGE_DIRTY
542	 * B <-> _PAGE_DMB (memory break)
543	 *
544	 * Then incredible subtlety: The access rights are
545	 * _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE
546	 * See 3-14 of the parisc 2.0 manual
547	 *
548	 * Finally, _PAGE_READ goes in the top bit of PL1 (so we
549	 * trigger an access rights trap in user space if the user
550	 * tries to read an unreadable page */
551	depd            \pte,8,7,\prot
552
553	/* PAGE_USER indicates the page can be read with user privileges,
554	 * so deposit X1|11 to PL1|PL2 (remember the upper bit of PL1
555	 * contains _PAGE_READ) */
556	extrd,u,*=      \pte,_PAGE_USER_BIT+32,1,%r0
557	depdi		7,11,3,\prot
558	/* If we're a gateway page, drop PL2 back to zero for promotion
559	 * to kernel privilege (so we can execute the page as kernel).
560	 * Any privilege promotion page always denys read and write */
561	extrd,u,*= 	\pte,_PAGE_GATEWAY_BIT+32,1,%r0
562	depd		%r0,11,2,\prot	/* If Gateway, Set PL2 to 0 */
563
564	/* Enforce uncacheable pages.
565	 * This should ONLY be use for MMIO on PA 2.0 machines.
566	 * Memory/DMA is cache coherent on all PA2.0 machines we support
567	 * (that means T-class is NOT supported) and the memory controllers
568	 * on most of those machines only handles cache transactions.
569	 */
570	extrd,u,*=	\pte,_PAGE_NO_CACHE_BIT+32,1,%r0
571	depdi		1,12,1,\prot
572
573	/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
574	convert_for_tlb_insert20 \pte \tmp
575	.endm
576
577	/* Identical macro to make_insert_tlb above, except it
578	 * makes the tlb entry for the differently formatted pa11
579	 * insertion instructions */
580	.macro		make_insert_tlb_11	spc,pte,prot
581	zdep		\spc,30,15,\prot
582	dep		\pte,8,7,\prot
583	extru,=		\pte,_PAGE_NO_CACHE_BIT,1,%r0
584	depi		1,12,1,\prot
585	extru,=         \pte,_PAGE_USER_BIT,1,%r0
586	depi		7,11,3,\prot   /* Set for user space (1 rsvd for read) */
587	extru,= 	\pte,_PAGE_GATEWAY_BIT,1,%r0
588	depi		0,11,2,\prot	/* If Gateway, Set PL2 to 0 */
589
590	/* Get rid of prot bits and convert to page addr for iitlba */
591
592	depi		0,31,ASM_PFN_PTE_SHIFT,\pte
593	SHRREG		\pte,(ASM_PFN_PTE_SHIFT-(31-26)),\pte
594	.endm
595
596	/* This is for ILP32 PA2.0 only.  The TLB insertion needs
597	 * to extend into I/O space if the address is 0xfXXXXXXX
598	 * so we extend the f's into the top word of the pte in
599	 * this case */
600	.macro		f_extend	pte,tmp
601	extrd,s		\pte,42,4,\tmp
602	addi,<>		1,\tmp,%r0
603	extrd,s		\pte,63,25,\pte
604	.endm
605
606	/* The alias region is an 8MB aligned 16MB to do clear and
607	 * copy user pages at addresses congruent with the user
608	 * virtual address.
609	 *
610	 * To use the alias page, you set %r26 up with the to TLB
611	 * entry (identifying the physical page) and %r23 up with
612	 * the from tlb entry (or nothing if only a to entry---for
613	 * clear_user_page_asm) */
614	.macro		do_alias	spc,tmp,tmp1,va,pte,prot,fault,patype
615	cmpib,COND(<>),n 0,\spc,\fault
616	ldil		L%(TMPALIAS_MAP_START),\tmp
617#if defined(CONFIG_64BIT) && (TMPALIAS_MAP_START >= 0x80000000)
618	/* on LP64, ldi will sign extend into the upper 32 bits,
619	 * which is behaviour we don't want */
620	depdi		0,31,32,\tmp
621#endif
622	copy		\va,\tmp1
623	depi		0,31,23,\tmp1
624	cmpb,COND(<>),n	\tmp,\tmp1,\fault
625	mfctl		%cr19,\tmp	/* iir */
626	/* get the opcode (first six bits) into \tmp */
627	extrw,u		\tmp,5,6,\tmp
628	/*
629	 * Only setting the T bit prevents data cache movein
630	 * Setting access rights to zero prevents instruction cache movein
631	 *
632	 * Note subtlety here: _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE go
633	 * to type field and _PAGE_READ goes to top bit of PL1
634	 */
635	ldi		(_PAGE_REFTRAP|_PAGE_READ|_PAGE_WRITE),\prot
636	/*
637	 * so if the opcode is one (i.e. this is a memory management
638	 * instruction) nullify the next load so \prot is only T.
639	 * Otherwise this is a normal data operation
640	 */
641	cmpiclr,=	0x01,\tmp,%r0
642	ldi		(_PAGE_DIRTY|_PAGE_READ|_PAGE_WRITE),\prot
643.ifc \patype,20
644	depd,z		\prot,8,7,\prot
645.else
646.ifc \patype,11
647	depw,z		\prot,8,7,\prot
648.else
649	.error "undefined PA type to do_alias"
650.endif
651.endif
652	/*
653	 * OK, it is in the temp alias region, check whether "from" or "to".
654	 * Check "subtle" note in pacache.S re: r23/r26.
655	 */
656#ifdef CONFIG_64BIT
657	extrd,u,*=	\va,41,1,%r0
658#else
659	extrw,u,=	\va,9,1,%r0
660#endif
661	or,COND(tr)	%r23,%r0,\pte
662	or		%r26,%r0,\pte
663	.endm
664
665
666	/*
667	 * Fault_vectors are architecturally required to be aligned on a 2K
668	 * boundary
669	 */
670
671	.section .text.hot
672	.align 2048
673
674ENTRY(fault_vector_20)
675	/* First vector is invalid (0) */
676	.ascii	"cows can fly"
677	.byte 0
678	.align 32
679
680	hpmc		 1
681	def		 2
682	def		 3
683	extint		 4
684	def		 5
685	itlb_20		 PARISC_ITLB_TRAP
686	def		 7
687	def		 8
688	def              9
689	def		10
690	def		11
691	def		12
692	def		13
693	def		14
694	dtlb_20		15
695	naitlb_20	16
696	nadtlb_20	17
697	def		18
698	def		19
699	dbit_20		20
700	def		21
701	def		22
702	def		23
703	def		24
704	def		25
705	def		26
706	def		27
707	def		28
708	def		29
709	def		30
710	def		31
711END(fault_vector_20)
712
713#ifndef CONFIG_64BIT
714
715	.align 2048
716
717ENTRY(fault_vector_11)
718	/* First vector is invalid (0) */
719	.ascii	"cows can fly"
720	.byte 0
721	.align 32
722
723	hpmc		 1
724	def		 2
725	def		 3
726	extint		 4
727	def		 5
728	itlb_11		 PARISC_ITLB_TRAP
729	def		 7
730	def		 8
731	def              9
732	def		10
733	def		11
734	def		12
735	def		13
736	def		14
737	dtlb_11		15
738	naitlb_11	16
739	nadtlb_11	17
740	def		18
741	def		19
742	dbit_11		20
743	def		21
744	def		22
745	def		23
746	def		24
747	def		25
748	def		26
749	def		27
750	def		28
751	def		29
752	def		30
753	def		31
754END(fault_vector_11)
755
756#endif
757	/* Fault vector is separately protected and *must* be on its own page */
758	.align		PAGE_SIZE
759
760	.import		handle_interruption,code
761	.import		do_cpu_irq_mask,code
762
763	/*
764	 * Child Returns here
765	 *
766	 * copy_thread moved args into task save area.
767	 */
768
769ENTRY(ret_from_kernel_thread)
770	/* Call schedule_tail first though */
771	BL	schedule_tail, %r2
772	nop
773
774	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
775	LDREG	TASK_PT_GR25(%r1), %r26
776#ifdef CONFIG_64BIT
777	LDREG	TASK_PT_GR27(%r1), %r27
778#endif
779	LDREG	TASK_PT_GR26(%r1), %r1
780	ble	0(%sr7, %r1)
781	copy	%r31, %r2
782	b	finish_child_return
783	nop
784END(ret_from_kernel_thread)
785
786
787	/*
788	 * struct task_struct *_switch_to(struct task_struct *prev,
789	 *	struct task_struct *next)
790	 *
791	 * switch kernel stacks and return prev */
792ENTRY_CFI(_switch_to)
793	STREG	 %r2, -RP_OFFSET(%r30)
794
795	callee_save_float
796	callee_save
797
798	load32	_switch_to_ret, %r2
799
800	STREG	%r2, TASK_PT_KPC(%r26)
801	LDREG	TASK_PT_KPC(%r25), %r2
802
803	STREG	%r30, TASK_PT_KSP(%r26)
804	LDREG	TASK_PT_KSP(%r25), %r30
805	LDREG	TASK_THREAD_INFO(%r25), %r25
806	bv	%r0(%r2)
807	mtctl   %r25,%cr30
808
809ENTRY(_switch_to_ret)
810	mtctl	%r0, %cr0		/* Needed for single stepping */
811	callee_rest
812	callee_rest_float
813
814	LDREG	-RP_OFFSET(%r30), %r2
815	bv	%r0(%r2)
816	copy	%r26, %r28
817ENDPROC_CFI(_switch_to)
818
819	/*
820	 * Common rfi return path for interruptions, kernel execve, and
821	 * sys_rt_sigreturn (sometimes).  The sys_rt_sigreturn syscall will
822	 * return via this path if the signal was received when the process
823	 * was running; if the process was blocked on a syscall then the
824	 * normal syscall_exit path is used.  All syscalls for traced
825	 * proceses exit via intr_restore.
826	 *
827	 * XXX If any syscalls that change a processes space id ever exit
828	 * this way, then we will need to copy %sr3 in to PT_SR[3..7], and
829	 * adjust IASQ[0..1].
830	 *
831	 */
832
833	.align	PAGE_SIZE
834
835ENTRY_CFI(syscall_exit_rfi)
836	mfctl   %cr30,%r16
837	LDREG	TI_TASK(%r16), %r16	/* thread_info -> task_struct */
838	ldo	TASK_REGS(%r16),%r16
839	/* Force iaoq to userspace, as the user has had access to our current
840	 * context via sigcontext. Also Filter the PSW for the same reason.
841	 */
842	LDREG	PT_IAOQ0(%r16),%r19
843	depi	3,31,2,%r19
844	STREG	%r19,PT_IAOQ0(%r16)
845	LDREG	PT_IAOQ1(%r16),%r19
846	depi	3,31,2,%r19
847	STREG	%r19,PT_IAOQ1(%r16)
848	LDREG   PT_PSW(%r16),%r19
849	load32	USER_PSW_MASK,%r1
850#ifdef CONFIG_64BIT
851	load32	USER_PSW_HI_MASK,%r20
852	depd    %r20,31,32,%r1
853#endif
854	and     %r19,%r1,%r19 /* Mask out bits that user shouldn't play with */
855	load32	USER_PSW,%r1
856	or      %r19,%r1,%r19 /* Make sure default USER_PSW bits are set */
857	STREG   %r19,PT_PSW(%r16)
858
859	/*
860	 * If we aren't being traced, we never saved space registers
861	 * (we don't store them in the sigcontext), so set them
862	 * to "proper" values now (otherwise we'll wind up restoring
863	 * whatever was last stored in the task structure, which might
864	 * be inconsistent if an interrupt occurred while on the gateway
865	 * page). Note that we may be "trashing" values the user put in
866	 * them, but we don't support the user changing them.
867	 */
868
869	STREG   %r0,PT_SR2(%r16)
870	mfsp    %sr3,%r19
871	STREG   %r19,PT_SR0(%r16)
872	STREG   %r19,PT_SR1(%r16)
873	STREG   %r19,PT_SR3(%r16)
874	STREG   %r19,PT_SR4(%r16)
875	STREG   %r19,PT_SR5(%r16)
876	STREG   %r19,PT_SR6(%r16)
877	STREG   %r19,PT_SR7(%r16)
878
879ENTRY(intr_return)
880	/* check for reschedule */
881	mfctl   %cr30,%r1
882	LDREG   TI_FLAGS(%r1),%r19	/* sched.h: TIF_NEED_RESCHED */
883	bb,<,n	%r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */
884
885	.import do_notify_resume,code
886intr_check_sig:
887	/* As above */
888	mfctl   %cr30,%r1
889	LDREG	TI_FLAGS(%r1),%r19
890	ldi	(_TIF_USER_WORK_MASK & ~_TIF_NEED_RESCHED), %r20
891	and,COND(<>)	%r19, %r20, %r0
892	b,n	intr_restore	/* skip past if we've nothing to do */
893
894	/* This check is critical to having LWS
895	 * working. The IASQ is zero on the gateway
896	 * page and we cannot deliver any signals until
897	 * we get off the gateway page.
898	 *
899	 * Only do signals if we are returning to user space
900	 */
901	LDREG	PT_IASQ0(%r16), %r20
902	cmpib,COND(=),n LINUX_GATEWAY_SPACE, %r20, intr_restore /* forward */
903	LDREG	PT_IASQ1(%r16), %r20
904	cmpib,COND(=),n LINUX_GATEWAY_SPACE, %r20, intr_restore /* forward */
905
906	copy	%r0, %r25			/* long in_syscall = 0 */
907#ifdef CONFIG_64BIT
908	ldo	-16(%r30),%r29			/* Reference param save area */
909#endif
910
911	/* NOTE: We need to enable interrupts if we have to deliver
912	 * signals. We used to do this earlier but it caused kernel
913	 * stack overflows. */
914	ssm	PSW_SM_I, %r0
915
916	BL	do_notify_resume,%r2
917	copy	%r16, %r26			/* struct pt_regs *regs */
918
919	b,n	intr_check_sig
920
921intr_restore:
922	copy            %r16,%r29
923	ldo             PT_FR31(%r29),%r1
924	rest_fp         %r1
925	rest_general    %r29
926
927	/* inverse of virt_map */
928	pcxt_ssm_bug
929	rsm             PSW_SM_QUIET,%r0	/* prepare for rfi */
930	tophys_r1       %r29
931
932	/* Restore space id's and special cr's from PT_REGS
933	 * structure pointed to by r29
934	 */
935	rest_specials	%r29
936
937	/* IMPORTANT: rest_stack restores r29 last (we are using it)!
938	 * It also restores r1 and r30.
939	 */
940	rest_stack
941
942	rfi
943	nop
944
945#ifndef CONFIG_PREEMPTION
946# define intr_do_preempt	intr_restore
947#endif /* !CONFIG_PREEMPTION */
948
949	.import schedule,code
950intr_do_resched:
951	/* Only call schedule on return to userspace. If we're returning
952	 * to kernel space, we may schedule if CONFIG_PREEMPTION, otherwise
953	 * we jump back to intr_restore.
954	 */
955	LDREG	PT_IASQ0(%r16), %r20
956	cmpib,COND(=)	0, %r20, intr_do_preempt
957	nop
958	LDREG	PT_IASQ1(%r16), %r20
959	cmpib,COND(=)	0, %r20, intr_do_preempt
960	nop
961
962	/* NOTE: We need to enable interrupts if we schedule.  We used
963	 * to do this earlier but it caused kernel stack overflows. */
964	ssm     PSW_SM_I, %r0
965
966#ifdef CONFIG_64BIT
967	ldo	-16(%r30),%r29		/* Reference param save area */
968#endif
969
970	ldil	L%intr_check_sig, %r2
971#ifndef CONFIG_64BIT
972	b	schedule
973#else
974	load32	schedule, %r20
975	bv	%r0(%r20)
976#endif
977	ldo	R%intr_check_sig(%r2), %r2
978
979	/* preempt the current task on returning to kernel
980	 * mode from an interrupt, iff need_resched is set,
981	 * and preempt_count is 0. otherwise, we continue on
982	 * our merry way back to the current running task.
983	 */
984#ifdef CONFIG_PREEMPTION
985	.import preempt_schedule_irq,code
986intr_do_preempt:
987	rsm	PSW_SM_I, %r0		/* disable interrupts */
988
989	/* current_thread_info()->preempt_count */
990	mfctl	%cr30, %r1
991	LDREG	TI_PRE_COUNT(%r1), %r19
992	cmpib,COND(<>)	0, %r19, intr_restore	/* if preempt_count > 0 */
993	nop				/* prev insn branched backwards */
994
995	/* check if we interrupted a critical path */
996	LDREG	PT_PSW(%r16), %r20
997	bb,<,n	%r20, 31 - PSW_SM_I, intr_restore
998	nop
999
1000	/* ssm PSW_SM_I done later in intr_restore */
1001#ifdef CONFIG_MLONGCALLS
1002	ldil	L%intr_restore, %r2
1003	load32	preempt_schedule_irq, %r1
1004	bv	%r0(%r1)
1005	ldo	R%intr_restore(%r2), %r2
1006#else
1007	ldil	L%intr_restore, %r1
1008	BL	preempt_schedule_irq, %r2
1009	ldo	R%intr_restore(%r1), %r2
1010#endif
1011#endif /* CONFIG_PREEMPTION */
1012
1013	/*
1014	 * External interrupts.
1015	 */
1016
1017intr_extint:
1018	cmpib,COND(=),n 0,%r16,1f
1019
1020	get_stack_use_cr30
1021	b,n 2f
1022
10231:
1024	get_stack_use_r30
10252:
1026	save_specials	%r29
1027	virt_map
1028	save_general	%r29
1029
1030	ldo	PT_FR0(%r29), %r24
1031	save_fp	%r24
1032
1033	loadgp
1034
1035	copy	%r29, %r26	/* arg0 is pt_regs */
1036	copy	%r29, %r16	/* save pt_regs */
1037
1038	ldil	L%intr_return, %r2
1039
1040#ifdef CONFIG_64BIT
1041	ldo	-16(%r30),%r29	/* Reference param save area */
1042#endif
1043
1044	b	do_cpu_irq_mask
1045	ldo	R%intr_return(%r2), %r2	/* return to intr_return, not here */
1046ENDPROC_CFI(syscall_exit_rfi)
1047
1048
1049	/* Generic interruptions (illegal insn, unaligned, page fault, etc) */
1050
1051ENTRY_CFI(intr_save)		/* for os_hpmc */
1052	mfsp    %sr7,%r16
1053	cmpib,COND(=),n 0,%r16,1f
1054	get_stack_use_cr30
1055	b	2f
1056	copy    %r8,%r26
1057
10581:
1059	get_stack_use_r30
1060	copy    %r8,%r26
1061
10622:
1063	save_specials	%r29
1064
1065	/* If this trap is a itlb miss, skip saving/adjusting isr/ior */
1066	cmpib,COND(=),n        PARISC_ITLB_TRAP,%r26,skip_save_ior
1067
1068
1069	mfctl           %isr, %r16
1070	nop		/* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */
1071	mfctl           %ior, %r17
1072
1073
1074#ifdef CONFIG_64BIT
1075	/*
1076	 * If the interrupted code was running with W bit off (32 bit),
1077	 * clear the b bits (bits 0 & 1) in the ior.
1078	 * save_specials left ipsw value in r8 for us to test.
1079	 */
1080	extrd,u,*<>     %r8,PSW_W_BIT,1,%r0
1081	depdi           0,1,2,%r17
1082
1083	/* adjust isr/ior: get high bits from isr and deposit in ior */
1084	space_adjust	%r16,%r17,%r1
1085#endif
1086	STREG           %r16, PT_ISR(%r29)
1087	STREG           %r17, PT_IOR(%r29)
1088
1089#if 0 && defined(CONFIG_64BIT)
1090	/* Revisit when we have 64-bit code above 4Gb */
1091	b,n		intr_save2
1092
1093skip_save_ior:
1094	/* We have a itlb miss, and when executing code above 4 Gb on ILP64, we
1095	 * need to adjust iasq/iaoq here in the same way we adjusted isr/ior
1096	 * above.
1097	 */
1098	extrd,u,*	%r8,PSW_W_BIT,1,%r1
1099	cmpib,COND(=),n	1,%r1,intr_save2
1100	LDREG		PT_IASQ0(%r29), %r16
1101	LDREG		PT_IAOQ0(%r29), %r17
1102	/* adjust iasq/iaoq */
1103	space_adjust	%r16,%r17,%r1
1104	STREG           %r16, PT_IASQ0(%r29)
1105	STREG           %r17, PT_IAOQ0(%r29)
1106#else
1107skip_save_ior:
1108#endif
1109
1110intr_save2:
1111	virt_map
1112	save_general	%r29
1113
1114	ldo		PT_FR0(%r29), %r25
1115	save_fp		%r25
1116
1117	loadgp
1118
1119	copy		%r29, %r25	/* arg1 is pt_regs */
1120#ifdef CONFIG_64BIT
1121	ldo		-16(%r30),%r29	/* Reference param save area */
1122#endif
1123
1124	ldil		L%intr_check_sig, %r2
1125	copy		%r25, %r16	/* save pt_regs */
1126
1127	b		handle_interruption
1128	ldo		R%intr_check_sig(%r2), %r2
1129ENDPROC_CFI(intr_save)
1130
1131
1132	/*
1133	 * Note for all tlb miss handlers:
1134	 *
1135	 * cr24 contains a pointer to the kernel address space
1136	 * page directory.
1137	 *
1138	 * cr25 contains a pointer to the current user address
1139	 * space page directory.
1140	 *
1141	 * sr3 will contain the space id of the user address space
1142	 * of the current running thread while that thread is
1143	 * running in the kernel.
1144	 */
1145
1146	/*
1147	 * register number allocations.  Note that these are all
1148	 * in the shadowed registers
1149	 */
1150
1151	t0 = r1		/* temporary register 0 */
1152	va = r8		/* virtual address for which the trap occurred */
1153	t1 = r9		/* temporary register 1 */
1154	pte  = r16	/* pte/phys page # */
1155	prot = r17	/* prot bits */
1156	spc  = r24	/* space for which the trap occurred */
1157	ptp = r25	/* page directory/page table pointer */
1158
1159#ifdef CONFIG_64BIT
1160
1161dtlb_miss_20w:
1162	space_adjust	spc,va,t0
1163	get_pgd		spc,ptp
1164	space_check	spc,t0,dtlb_fault
1165
1166	L3_ptep		ptp,pte,t0,va,dtlb_check_alias_20w
1167
1168	tlb_lock	spc,ptp,pte,t0,t1,dtlb_check_alias_20w
1169	update_accessed	ptp,pte,t0,t1
1170
1171	make_insert_tlb	spc,pte,prot,t1
1172
1173	idtlbt          pte,prot
1174
1175	tlb_unlock1	spc,t0
1176	rfir
1177	nop
1178
1179dtlb_check_alias_20w:
1180	do_alias	spc,t0,t1,va,pte,prot,dtlb_fault,20
1181
1182	idtlbt          pte,prot
1183
1184	rfir
1185	nop
1186
1187nadtlb_miss_20w:
1188	space_adjust	spc,va,t0
1189	get_pgd		spc,ptp
1190	space_check	spc,t0,nadtlb_fault
1191
1192	L3_ptep		ptp,pte,t0,va,nadtlb_check_alias_20w
1193
1194	tlb_lock	spc,ptp,pte,t0,t1,nadtlb_check_alias_20w
1195	update_accessed	ptp,pte,t0,t1
1196
1197	make_insert_tlb	spc,pte,prot,t1
1198
1199	idtlbt          pte,prot
1200
1201	tlb_unlock1	spc,t0
1202	rfir
1203	nop
1204
1205nadtlb_check_alias_20w:
1206	do_alias	spc,t0,t1,va,pte,prot,nadtlb_emulate,20
1207
1208	idtlbt          pte,prot
1209
1210	rfir
1211	nop
1212
1213#else
1214
1215dtlb_miss_11:
1216	get_pgd		spc,ptp
1217
1218	space_check	spc,t0,dtlb_fault
1219
1220	L2_ptep		ptp,pte,t0,va,dtlb_check_alias_11
1221
1222	tlb_lock	spc,ptp,pte,t0,t1,dtlb_check_alias_11
1223	update_accessed	ptp,pte,t0,t1
1224
1225	make_insert_tlb_11	spc,pte,prot
1226
1227	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1228	mtsp		spc,%sr1
1229
1230	idtlba		pte,(%sr1,va)
1231	idtlbp		prot,(%sr1,va)
1232
1233	mtsp		t1, %sr1	/* Restore sr1 */
1234
1235	tlb_unlock1	spc,t0
1236	rfir
1237	nop
1238
1239dtlb_check_alias_11:
1240	do_alias	spc,t0,t1,va,pte,prot,dtlb_fault,11
1241
1242	idtlba          pte,(va)
1243	idtlbp          prot,(va)
1244
1245	rfir
1246	nop
1247
1248nadtlb_miss_11:
1249	get_pgd		spc,ptp
1250
1251	space_check	spc,t0,nadtlb_fault
1252
1253	L2_ptep		ptp,pte,t0,va,nadtlb_check_alias_11
1254
1255	tlb_lock	spc,ptp,pte,t0,t1,nadtlb_check_alias_11
1256	update_accessed	ptp,pte,t0,t1
1257
1258	make_insert_tlb_11	spc,pte,prot
1259
1260	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1261	mtsp		spc,%sr1
1262
1263	idtlba		pte,(%sr1,va)
1264	idtlbp		prot,(%sr1,va)
1265
1266	mtsp		t1, %sr1	/* Restore sr1 */
1267
1268	tlb_unlock1	spc,t0
1269	rfir
1270	nop
1271
1272nadtlb_check_alias_11:
1273	do_alias	spc,t0,t1,va,pte,prot,nadtlb_emulate,11
1274
1275	idtlba          pte,(va)
1276	idtlbp          prot,(va)
1277
1278	rfir
1279	nop
1280
1281dtlb_miss_20:
1282	space_adjust	spc,va,t0
1283	get_pgd		spc,ptp
1284	space_check	spc,t0,dtlb_fault
1285
1286	L2_ptep		ptp,pte,t0,va,dtlb_check_alias_20
1287
1288	tlb_lock	spc,ptp,pte,t0,t1,dtlb_check_alias_20
1289	update_accessed	ptp,pte,t0,t1
1290
1291	make_insert_tlb	spc,pte,prot,t1
1292
1293	f_extend	pte,t1
1294
1295	idtlbt          pte,prot
1296
1297	tlb_unlock1	spc,t0
1298	rfir
1299	nop
1300
1301dtlb_check_alias_20:
1302	do_alias	spc,t0,t1,va,pte,prot,dtlb_fault,20
1303
1304	idtlbt          pte,prot
1305
1306	rfir
1307	nop
1308
1309nadtlb_miss_20:
1310	get_pgd		spc,ptp
1311
1312	space_check	spc,t0,nadtlb_fault
1313
1314	L2_ptep		ptp,pte,t0,va,nadtlb_check_alias_20
1315
1316	tlb_lock	spc,ptp,pte,t0,t1,nadtlb_check_alias_20
1317	update_accessed	ptp,pte,t0,t1
1318
1319	make_insert_tlb	spc,pte,prot,t1
1320
1321	f_extend	pte,t1
1322
1323	idtlbt		pte,prot
1324
1325	tlb_unlock1	spc,t0
1326	rfir
1327	nop
1328
1329nadtlb_check_alias_20:
1330	do_alias	spc,t0,t1,va,pte,prot,nadtlb_emulate,20
1331
1332	idtlbt          pte,prot
1333
1334	rfir
1335	nop
1336
1337#endif
1338
1339nadtlb_emulate:
1340
1341	/*
1342	 * Non access misses can be caused by fdc,fic,pdc,lpa,probe and
1343	 * probei instructions. We don't want to fault for these
1344	 * instructions (not only does it not make sense, it can cause
1345	 * deadlocks, since some flushes are done with the mmap
1346	 * semaphore held). If the translation doesn't exist, we can't
1347	 * insert a translation, so have to emulate the side effects
1348	 * of the instruction. Since we don't insert a translation
1349	 * we can get a lot of faults during a flush loop, so it makes
1350	 * sense to try to do it here with minimum overhead. We only
1351	 * emulate fdc,fic,pdc,probew,prober instructions whose base
1352	 * and index registers are not shadowed. We defer everything
1353	 * else to the "slow" path.
1354	 */
1355
1356	mfctl           %cr19,%r9 /* Get iir */
1357
1358	/* PA 2.0 Arch Ref. Book pg 382 has a good description of the insn bits.
1359	   Checks for fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw */
1360
1361	/* Checks for fdc,fdce,pdc,"fic,4f" only */
1362	ldi             0x280,%r16
1363	and             %r9,%r16,%r17
1364	cmpb,<>,n       %r16,%r17,nadtlb_probe_check
1365	bb,>=,n         %r9,26,nadtlb_nullify  /* m bit not set, just nullify */
1366	BL		get_register,%r25
1367	extrw,u         %r9,15,5,%r8           /* Get index register # */
1368	cmpib,COND(=),n        -1,%r1,nadtlb_fault    /* have to use slow path */
1369	copy            %r1,%r24
1370	BL		get_register,%r25
1371	extrw,u         %r9,10,5,%r8           /* Get base register # */
1372	cmpib,COND(=),n        -1,%r1,nadtlb_fault    /* have to use slow path */
1373	BL		set_register,%r25
1374	add,l           %r1,%r24,%r1           /* doesn't affect c/b bits */
1375
1376nadtlb_nullify:
1377	mfctl           %ipsw,%r8
1378	ldil            L%PSW_N,%r9
1379	or              %r8,%r9,%r8            /* Set PSW_N */
1380	mtctl           %r8,%ipsw
1381
1382	rfir
1383	nop
1384
1385	/*
1386		When there is no translation for the probe address then we
1387		must nullify the insn and return zero in the target register.
1388		This will indicate to the calling code that it does not have
1389		write/read privileges to this address.
1390
1391		This should technically work for prober and probew in PA 1.1,
1392		and also probe,r and probe,w in PA 2.0
1393
1394		WARNING: USE ONLY NON-SHADOW REGISTERS WITH PROBE INSN!
1395		THE SLOW-PATH EMULATION HAS NOT BEEN WRITTEN YET.
1396
1397	*/
1398nadtlb_probe_check:
1399	ldi             0x80,%r16
1400	and             %r9,%r16,%r17
1401	cmpb,<>,n       %r16,%r17,nadtlb_fault /* Must be probe,[rw]*/
1402	BL              get_register,%r25      /* Find the target register */
1403	extrw,u         %r9,31,5,%r8           /* Get target register */
1404	cmpib,COND(=),n        -1,%r1,nadtlb_fault    /* have to use slow path */
1405	BL		set_register,%r25
1406	copy            %r0,%r1                /* Write zero to target register */
1407	b nadtlb_nullify                       /* Nullify return insn */
1408	nop
1409
1410
1411#ifdef CONFIG_64BIT
1412itlb_miss_20w:
1413
1414	/*
1415	 * I miss is a little different, since we allow users to fault
1416	 * on the gateway page which is in the kernel address space.
1417	 */
1418
1419	space_adjust	spc,va,t0
1420	get_pgd		spc,ptp
1421	space_check	spc,t0,itlb_fault
1422
1423	L3_ptep		ptp,pte,t0,va,itlb_fault
1424
1425	tlb_lock	spc,ptp,pte,t0,t1,itlb_fault
1426	update_accessed	ptp,pte,t0,t1
1427
1428	make_insert_tlb	spc,pte,prot,t1
1429
1430	iitlbt          pte,prot
1431
1432	tlb_unlock1	spc,t0
1433	rfir
1434	nop
1435
1436naitlb_miss_20w:
1437
1438	/*
1439	 * I miss is a little different, since we allow users to fault
1440	 * on the gateway page which is in the kernel address space.
1441	 */
1442
1443	space_adjust	spc,va,t0
1444	get_pgd		spc,ptp
1445	space_check	spc,t0,naitlb_fault
1446
1447	L3_ptep		ptp,pte,t0,va,naitlb_check_alias_20w
1448
1449	tlb_lock	spc,ptp,pte,t0,t1,naitlb_check_alias_20w
1450	update_accessed	ptp,pte,t0,t1
1451
1452	make_insert_tlb	spc,pte,prot,t1
1453
1454	iitlbt          pte,prot
1455
1456	tlb_unlock1	spc,t0
1457	rfir
1458	nop
1459
1460naitlb_check_alias_20w:
1461	do_alias	spc,t0,t1,va,pte,prot,naitlb_fault,20
1462
1463	iitlbt		pte,prot
1464
1465	rfir
1466	nop
1467
1468#else
1469
1470itlb_miss_11:
1471	get_pgd		spc,ptp
1472
1473	space_check	spc,t0,itlb_fault
1474
1475	L2_ptep		ptp,pte,t0,va,itlb_fault
1476
1477	tlb_lock	spc,ptp,pte,t0,t1,itlb_fault
1478	update_accessed	ptp,pte,t0,t1
1479
1480	make_insert_tlb_11	spc,pte,prot
1481
1482	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1483	mtsp		spc,%sr1
1484
1485	iitlba		pte,(%sr1,va)
1486	iitlbp		prot,(%sr1,va)
1487
1488	mtsp		t1, %sr1	/* Restore sr1 */
1489
1490	tlb_unlock1	spc,t0
1491	rfir
1492	nop
1493
1494naitlb_miss_11:
1495	get_pgd		spc,ptp
1496
1497	space_check	spc,t0,naitlb_fault
1498
1499	L2_ptep		ptp,pte,t0,va,naitlb_check_alias_11
1500
1501	tlb_lock	spc,ptp,pte,t0,t1,naitlb_check_alias_11
1502	update_accessed	ptp,pte,t0,t1
1503
1504	make_insert_tlb_11	spc,pte,prot
1505
1506	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1507	mtsp		spc,%sr1
1508
1509	iitlba		pte,(%sr1,va)
1510	iitlbp		prot,(%sr1,va)
1511
1512	mtsp		t1, %sr1	/* Restore sr1 */
1513
1514	tlb_unlock1	spc,t0
1515	rfir
1516	nop
1517
1518naitlb_check_alias_11:
1519	do_alias	spc,t0,t1,va,pte,prot,itlb_fault,11
1520
1521	iitlba          pte,(%sr0, va)
1522	iitlbp          prot,(%sr0, va)
1523
1524	rfir
1525	nop
1526
1527
1528itlb_miss_20:
1529	get_pgd		spc,ptp
1530
1531	space_check	spc,t0,itlb_fault
1532
1533	L2_ptep		ptp,pte,t0,va,itlb_fault
1534
1535	tlb_lock	spc,ptp,pte,t0,t1,itlb_fault
1536	update_accessed	ptp,pte,t0,t1
1537
1538	make_insert_tlb	spc,pte,prot,t1
1539
1540	f_extend	pte,t1
1541
1542	iitlbt          pte,prot
1543
1544	tlb_unlock1	spc,t0
1545	rfir
1546	nop
1547
1548naitlb_miss_20:
1549	get_pgd		spc,ptp
1550
1551	space_check	spc,t0,naitlb_fault
1552
1553	L2_ptep		ptp,pte,t0,va,naitlb_check_alias_20
1554
1555	tlb_lock	spc,ptp,pte,t0,t1,naitlb_check_alias_20
1556	update_accessed	ptp,pte,t0,t1
1557
1558	make_insert_tlb	spc,pte,prot,t1
1559
1560	f_extend	pte,t1
1561
1562	iitlbt          pte,prot
1563
1564	tlb_unlock1	spc,t0
1565	rfir
1566	nop
1567
1568naitlb_check_alias_20:
1569	do_alias	spc,t0,t1,va,pte,prot,naitlb_fault,20
1570
1571	iitlbt          pte,prot
1572
1573	rfir
1574	nop
1575
1576#endif
1577
1578#ifdef CONFIG_64BIT
1579
1580dbit_trap_20w:
1581	space_adjust	spc,va,t0
1582	get_pgd		spc,ptp
1583	space_check	spc,t0,dbit_fault
1584
1585	L3_ptep		ptp,pte,t0,va,dbit_fault
1586
1587	tlb_lock	spc,ptp,pte,t0,t1,dbit_fault
1588	update_dirty	ptp,pte,t1
1589
1590	make_insert_tlb	spc,pte,prot,t1
1591
1592	idtlbt          pte,prot
1593
1594	tlb_unlock0	spc,t0
1595	rfir
1596	nop
1597#else
1598
1599dbit_trap_11:
1600
1601	get_pgd		spc,ptp
1602
1603	space_check	spc,t0,dbit_fault
1604
1605	L2_ptep		ptp,pte,t0,va,dbit_fault
1606
1607	tlb_lock	spc,ptp,pte,t0,t1,dbit_fault
1608	update_dirty	ptp,pte,t1
1609
1610	make_insert_tlb_11	spc,pte,prot
1611
1612	mfsp            %sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1613	mtsp		spc,%sr1
1614
1615	idtlba		pte,(%sr1,va)
1616	idtlbp		prot,(%sr1,va)
1617
1618	mtsp            t1, %sr1     /* Restore sr1 */
1619
1620	tlb_unlock0	spc,t0
1621	rfir
1622	nop
1623
1624dbit_trap_20:
1625	get_pgd		spc,ptp
1626
1627	space_check	spc,t0,dbit_fault
1628
1629	L2_ptep		ptp,pte,t0,va,dbit_fault
1630
1631	tlb_lock	spc,ptp,pte,t0,t1,dbit_fault
1632	update_dirty	ptp,pte,t1
1633
1634	make_insert_tlb	spc,pte,prot,t1
1635
1636	f_extend	pte,t1
1637
1638	idtlbt		pte,prot
1639
1640	tlb_unlock0	spc,t0
1641	rfir
1642	nop
1643#endif
1644
1645	.import handle_interruption,code
1646
1647kernel_bad_space:
1648	b               intr_save
1649	ldi             31,%r8  /* Use an unused code */
1650
1651dbit_fault:
1652	b               intr_save
1653	ldi             20,%r8
1654
1655itlb_fault:
1656	b               intr_save
1657	ldi             PARISC_ITLB_TRAP,%r8
1658
1659nadtlb_fault:
1660	b               intr_save
1661	ldi             17,%r8
1662
1663naitlb_fault:
1664	b               intr_save
1665	ldi             16,%r8
1666
1667dtlb_fault:
1668	b               intr_save
1669	ldi             15,%r8
1670
1671	/* Register saving semantics for system calls:
1672
1673	   %r1		   clobbered by system call macro in userspace
1674	   %r2		   saved in PT_REGS by gateway page
1675	   %r3  - %r18	   preserved by C code (saved by signal code)
1676	   %r19 - %r20	   saved in PT_REGS by gateway page
1677	   %r21 - %r22	   non-standard syscall args
1678			   stored in kernel stack by gateway page
1679	   %r23 - %r26	   arg3-arg0, saved in PT_REGS by gateway page
1680	   %r27 - %r30	   saved in PT_REGS by gateway page
1681	   %r31		   syscall return pointer
1682	 */
1683
1684	/* Floating point registers (FIXME: what do we do with these?)
1685
1686	   %fr0  - %fr3	   status/exception, not preserved
1687	   %fr4  - %fr7	   arguments
1688	   %fr8	 - %fr11   not preserved by C code
1689	   %fr12 - %fr21   preserved by C code
1690	   %fr22 - %fr31   not preserved by C code
1691	 */
1692
1693	.macro	reg_save regs
1694	STREG	%r3, PT_GR3(\regs)
1695	STREG	%r4, PT_GR4(\regs)
1696	STREG	%r5, PT_GR5(\regs)
1697	STREG	%r6, PT_GR6(\regs)
1698	STREG	%r7, PT_GR7(\regs)
1699	STREG	%r8, PT_GR8(\regs)
1700	STREG	%r9, PT_GR9(\regs)
1701	STREG   %r10,PT_GR10(\regs)
1702	STREG   %r11,PT_GR11(\regs)
1703	STREG   %r12,PT_GR12(\regs)
1704	STREG   %r13,PT_GR13(\regs)
1705	STREG   %r14,PT_GR14(\regs)
1706	STREG   %r15,PT_GR15(\regs)
1707	STREG   %r16,PT_GR16(\regs)
1708	STREG   %r17,PT_GR17(\regs)
1709	STREG   %r18,PT_GR18(\regs)
1710	.endm
1711
1712	.macro	reg_restore regs
1713	LDREG	PT_GR3(\regs), %r3
1714	LDREG	PT_GR4(\regs), %r4
1715	LDREG	PT_GR5(\regs), %r5
1716	LDREG	PT_GR6(\regs), %r6
1717	LDREG	PT_GR7(\regs), %r7
1718	LDREG	PT_GR8(\regs), %r8
1719	LDREG	PT_GR9(\regs), %r9
1720	LDREG   PT_GR10(\regs),%r10
1721	LDREG   PT_GR11(\regs),%r11
1722	LDREG   PT_GR12(\regs),%r12
1723	LDREG   PT_GR13(\regs),%r13
1724	LDREG   PT_GR14(\regs),%r14
1725	LDREG   PT_GR15(\regs),%r15
1726	LDREG   PT_GR16(\regs),%r16
1727	LDREG   PT_GR17(\regs),%r17
1728	LDREG   PT_GR18(\regs),%r18
1729	.endm
1730
1731	.macro	fork_like name
1732ENTRY_CFI(sys_\name\()_wrapper)
1733	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
1734	ldo	TASK_REGS(%r1),%r1
1735	reg_save %r1
1736	mfctl	%cr27, %r28
1737	ldil	L%sys_\name, %r31
1738	be	R%sys_\name(%sr4,%r31)
1739	STREG	%r28, PT_CR27(%r1)
1740ENDPROC_CFI(sys_\name\()_wrapper)
1741	.endm
1742
1743fork_like clone
1744fork_like clone3
1745fork_like fork
1746fork_like vfork
1747
1748	/* Set the return value for the child */
1749ENTRY(child_return)
1750	BL	schedule_tail, %r2
1751	nop
1752finish_child_return:
1753	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
1754	ldo	TASK_REGS(%r1),%r1	 /* get pt regs */
1755
1756	LDREG	PT_CR27(%r1), %r3
1757	mtctl	%r3, %cr27
1758	reg_restore %r1
1759	b	syscall_exit
1760	copy	%r0,%r28
1761END(child_return)
1762
1763ENTRY_CFI(sys_rt_sigreturn_wrapper)
1764	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26
1765	ldo	TASK_REGS(%r26),%r26	/* get pt regs */
1766	/* Don't save regs, we are going to restore them from sigcontext. */
1767	STREG	%r2, -RP_OFFSET(%r30)
1768#ifdef CONFIG_64BIT
1769	ldo	FRAME_SIZE(%r30), %r30
1770	BL	sys_rt_sigreturn,%r2
1771	ldo	-16(%r30),%r29		/* Reference param save area */
1772#else
1773	BL	sys_rt_sigreturn,%r2
1774	ldo	FRAME_SIZE(%r30), %r30
1775#endif
1776
1777	ldo	-FRAME_SIZE(%r30), %r30
1778	LDREG	-RP_OFFSET(%r30), %r2
1779
1780	/* FIXME: I think we need to restore a few more things here. */
1781	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1782	ldo	TASK_REGS(%r1),%r1	/* get pt regs */
1783	reg_restore %r1
1784
1785	/* If the signal was received while the process was blocked on a
1786	 * syscall, then r2 will take us to syscall_exit; otherwise r2 will
1787	 * take us to syscall_exit_rfi and on to intr_return.
1788	 */
1789	bv	%r0(%r2)
1790	LDREG	PT_GR28(%r1),%r28  /* reload original r28 for syscall_exit */
1791ENDPROC_CFI(sys_rt_sigreturn_wrapper)
1792
1793ENTRY(syscall_exit)
1794	/* NOTE: Not all syscalls exit this way.  rt_sigreturn will exit
1795	 * via syscall_exit_rfi if the signal was received while the process
1796	 * was running.
1797	 */
1798
1799	/* save return value now */
1800
1801	mfctl     %cr30, %r1
1802	LDREG     TI_TASK(%r1),%r1
1803	STREG     %r28,TASK_PT_GR28(%r1)
1804
1805	/* Seems to me that dp could be wrong here, if the syscall involved
1806	 * calling a module, and nothing got round to restoring dp on return.
1807	 */
1808	loadgp
1809
1810syscall_check_resched:
1811
1812	/* check for reschedule */
1813
1814	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19	/* long */
1815	bb,<,n	%r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */
1816
1817	.import do_signal,code
1818syscall_check_sig:
1819	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19
1820	ldi	(_TIF_USER_WORK_MASK & ~_TIF_NEED_RESCHED), %r26
1821	and,COND(<>)	%r19, %r26, %r0
1822	b,n	syscall_restore	/* skip past if we've nothing to do */
1823
1824syscall_do_signal:
1825	/* Save callee-save registers (for sigcontext).
1826	 * FIXME: After this point the process structure should be
1827	 * consistent with all the relevant state of the process
1828	 * before the syscall.  We need to verify this.
1829	 */
1830	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1831	ldo	TASK_REGS(%r1), %r26		/* struct pt_regs *regs */
1832	reg_save %r26
1833
1834#ifdef CONFIG_64BIT
1835	ldo	-16(%r30),%r29			/* Reference param save area */
1836#endif
1837
1838	BL	do_notify_resume,%r2
1839	ldi	1, %r25				/* long in_syscall = 1 */
1840
1841	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1842	ldo	TASK_REGS(%r1), %r20		/* reload pt_regs */
1843	reg_restore %r20
1844
1845	b,n     syscall_check_sig
1846
1847syscall_restore:
1848	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1849
1850	/* Are we being ptraced? */
1851	ldw	TASK_FLAGS(%r1),%r19
1852	ldi	_TIF_SYSCALL_TRACE_MASK,%r2
1853	and,COND(=)	%r19,%r2,%r0
1854	b,n	syscall_restore_rfi
1855
1856	ldo	TASK_PT_FR31(%r1),%r19		   /* reload fpregs */
1857	rest_fp	%r19
1858
1859	LDREG	TASK_PT_SAR(%r1),%r19		   /* restore SAR */
1860	mtsar	%r19
1861
1862	LDREG	TASK_PT_GR2(%r1),%r2		   /* restore user rp */
1863	LDREG	TASK_PT_GR19(%r1),%r19
1864	LDREG   TASK_PT_GR20(%r1),%r20
1865	LDREG	TASK_PT_GR21(%r1),%r21
1866	LDREG	TASK_PT_GR22(%r1),%r22
1867	LDREG	TASK_PT_GR23(%r1),%r23
1868	LDREG	TASK_PT_GR24(%r1),%r24
1869	LDREG	TASK_PT_GR25(%r1),%r25
1870	LDREG	TASK_PT_GR26(%r1),%r26
1871	LDREG	TASK_PT_GR27(%r1),%r27	   /* restore user dp */
1872	LDREG	TASK_PT_GR28(%r1),%r28	   /* syscall return value */
1873	LDREG	TASK_PT_GR29(%r1),%r29
1874	LDREG	TASK_PT_GR31(%r1),%r31	   /* restore syscall rp */
1875
1876	/* NOTE: We use rsm/ssm pair to make this operation atomic */
1877	LDREG   TASK_PT_GR30(%r1),%r1              /* Get user sp */
1878	rsm     PSW_SM_I, %r0
1879	copy    %r1,%r30                           /* Restore user sp */
1880	mfsp    %sr3,%r1                           /* Get user space id */
1881	mtsp    %r1,%sr7                           /* Restore sr7 */
1882	ssm     PSW_SM_I, %r0
1883
1884	/* Set sr2 to zero for userspace syscalls to work. */
1885	mtsp	%r0,%sr2
1886	mtsp	%r1,%sr4			   /* Restore sr4 */
1887	mtsp	%r1,%sr5			   /* Restore sr5 */
1888	mtsp	%r1,%sr6			   /* Restore sr6 */
1889
1890	depi	3,31,2,%r31			   /* ensure return to user mode. */
1891
1892#ifdef CONFIG_64BIT
1893	/* decide whether to reset the wide mode bit
1894	 *
1895	 * For a syscall, the W bit is stored in the lowest bit
1896	 * of sp.  Extract it and reset W if it is zero */
1897	extrd,u,*<>	%r30,63,1,%r1
1898	rsm	PSW_SM_W, %r0
1899	/* now reset the lowest bit of sp if it was set */
1900	xor	%r30,%r1,%r30
1901#endif
1902	be,n    0(%sr3,%r31)                       /* return to user space */
1903
1904	/* We have to return via an RFI, so that PSW T and R bits can be set
1905	 * appropriately.
1906	 * This sets up pt_regs so we can return via intr_restore, which is not
1907	 * the most efficient way of doing things, but it works.
1908	 */
1909syscall_restore_rfi:
1910	ldo	-1(%r0),%r2			   /* Set recovery cntr to -1 */
1911	mtctl	%r2,%cr0			   /*   for immediate trap */
1912	LDREG	TASK_PT_PSW(%r1),%r2		   /* Get old PSW */
1913	ldi	0x0b,%r20			   /* Create new PSW */
1914	depi	-1,13,1,%r20			   /* C, Q, D, and I bits */
1915
1916	/* The values of SINGLESTEP_BIT and BLOCKSTEP_BIT are
1917	 * set in thread_info.h and converted to PA bitmap
1918	 * numbers in asm-offsets.c */
1919
1920	/* if ((%r19.SINGLESTEP_BIT)) { %r20.27=1} */
1921	extru,=	%r19,TIF_SINGLESTEP_PA_BIT,1,%r0
1922	depi	-1,27,1,%r20			   /* R bit */
1923
1924	/* if ((%r19.BLOCKSTEP_BIT)) { %r20.7=1} */
1925	extru,= %r19,TIF_BLOCKSTEP_PA_BIT,1,%r0
1926	depi	-1,7,1,%r20			   /* T bit */
1927
1928	STREG	%r20,TASK_PT_PSW(%r1)
1929
1930	/* Always store space registers, since sr3 can be changed (e.g. fork) */
1931
1932	mfsp    %sr3,%r25
1933	STREG   %r25,TASK_PT_SR3(%r1)
1934	STREG   %r25,TASK_PT_SR4(%r1)
1935	STREG   %r25,TASK_PT_SR5(%r1)
1936	STREG   %r25,TASK_PT_SR6(%r1)
1937	STREG   %r25,TASK_PT_SR7(%r1)
1938	STREG   %r25,TASK_PT_IASQ0(%r1)
1939	STREG   %r25,TASK_PT_IASQ1(%r1)
1940
1941	/* XXX W bit??? */
1942	/* Now if old D bit is clear, it means we didn't save all registers
1943	 * on syscall entry, so do that now.  This only happens on TRACEME
1944	 * calls, or if someone attached to us while we were on a syscall.
1945	 * We could make this more efficient by not saving r3-r18, but
1946	 * then we wouldn't be able to use the common intr_restore path.
1947	 * It is only for traced processes anyway, so performance is not
1948	 * an issue.
1949	 */
1950	bb,<	%r2,30,pt_regs_ok		   /* Branch if D set */
1951	ldo	TASK_REGS(%r1),%r25
1952	reg_save %r25				   /* Save r3 to r18 */
1953
1954	/* Save the current sr */
1955	mfsp	%sr0,%r2
1956	STREG	%r2,TASK_PT_SR0(%r1)
1957
1958	/* Save the scratch sr */
1959	mfsp	%sr1,%r2
1960	STREG	%r2,TASK_PT_SR1(%r1)
1961
1962	/* sr2 should be set to zero for userspace syscalls */
1963	STREG	%r0,TASK_PT_SR2(%r1)
1964
1965	LDREG	TASK_PT_GR31(%r1),%r2
1966	depi	3,31,2,%r2		   /* ensure return to user mode. */
1967	STREG   %r2,TASK_PT_IAOQ0(%r1)
1968	ldo	4(%r2),%r2
1969	STREG	%r2,TASK_PT_IAOQ1(%r1)
1970	b	intr_restore
1971	copy	%r25,%r16
1972
1973pt_regs_ok:
1974	LDREG	TASK_PT_IAOQ0(%r1),%r2
1975	depi	3,31,2,%r2		   /* ensure return to user mode. */
1976	STREG	%r2,TASK_PT_IAOQ0(%r1)
1977	LDREG	TASK_PT_IAOQ1(%r1),%r2
1978	depi	3,31,2,%r2
1979	STREG	%r2,TASK_PT_IAOQ1(%r1)
1980	b	intr_restore
1981	copy	%r25,%r16
1982
1983syscall_do_resched:
1984	load32	syscall_check_resched,%r2 /* if resched, we start over again */
1985	load32	schedule,%r19
1986	bv	%r0(%r19)		/* jumps to schedule() */
1987#ifdef CONFIG_64BIT
1988	ldo	-16(%r30),%r29		/* Reference param save area */
1989#else
1990	nop
1991#endif
1992END(syscall_exit)
1993
1994
1995#ifdef CONFIG_FUNCTION_TRACER
1996
1997	.import ftrace_function_trampoline,code
1998	.align L1_CACHE_BYTES
1999ENTRY_CFI(mcount, caller)
2000_mcount:
2001	.export _mcount,data
2002	/*
2003	 * The 64bit mcount() function pointer needs 4 dwords, of which the
2004	 * first two are free.  We optimize it here and put 2 instructions for
2005	 * calling mcount(), and 2 instructions for ftrace_stub().  That way we
2006	 * have all on one L1 cacheline.
2007	 */
2008	ldi	0, %arg3
2009	b	ftrace_function_trampoline
2010	copy	%r3, %arg2	/* caller original %sp */
2011ftrace_stub:
2012	.globl ftrace_stub
2013        .type  ftrace_stub, @function
2014#ifdef CONFIG_64BIT
2015	bve	(%rp)
2016#else
2017	bv	%r0(%rp)
2018#endif
2019	nop
2020#ifdef CONFIG_64BIT
2021	.dword mcount
2022	.dword 0 /* code in head.S puts value of global gp here */
2023#endif
2024ENDPROC_CFI(mcount)
2025
2026#ifdef CONFIG_DYNAMIC_FTRACE
2027
2028#ifdef CONFIG_64BIT
2029#define FTRACE_FRAME_SIZE (2*FRAME_SIZE)
2030#else
2031#define FTRACE_FRAME_SIZE FRAME_SIZE
2032#endif
2033ENTRY_CFI(ftrace_caller, caller,frame=FTRACE_FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP)
2034ftrace_caller:
2035	.global ftrace_caller
2036
2037	STREG	%r3, -FTRACE_FRAME_SIZE+1*REG_SZ(%sp)
2038	ldo	-FTRACE_FRAME_SIZE(%sp), %r3
2039	STREG	%rp, -RP_OFFSET(%r3)
2040
2041	/* Offset 0 is already allocated for %r1 */
2042	STREG	%r23, 2*REG_SZ(%r3)
2043	STREG	%r24, 3*REG_SZ(%r3)
2044	STREG	%r25, 4*REG_SZ(%r3)
2045	STREG	%r26, 5*REG_SZ(%r3)
2046	STREG	%r28, 6*REG_SZ(%r3)
2047	STREG	%r29, 7*REG_SZ(%r3)
2048#ifdef CONFIG_64BIT
2049	STREG	%r19, 8*REG_SZ(%r3)
2050	STREG	%r20, 9*REG_SZ(%r3)
2051	STREG	%r21, 10*REG_SZ(%r3)
2052	STREG	%r22, 11*REG_SZ(%r3)
2053	STREG	%r27, 12*REG_SZ(%r3)
2054	STREG	%r31, 13*REG_SZ(%r3)
2055	loadgp
2056	ldo	-16(%sp),%r29
2057#endif
2058	LDREG	0(%r3), %r25
2059	copy	%rp, %r26
2060	ldo	-8(%r25), %r25
2061	ldi	0, %r23		/* no pt_regs */
2062	b,l	ftrace_function_trampoline, %rp
2063	copy	%r3, %r24
2064
2065	LDREG	-RP_OFFSET(%r3), %rp
2066	LDREG	2*REG_SZ(%r3), %r23
2067	LDREG	3*REG_SZ(%r3), %r24
2068	LDREG	4*REG_SZ(%r3), %r25
2069	LDREG	5*REG_SZ(%r3), %r26
2070	LDREG	6*REG_SZ(%r3), %r28
2071	LDREG	7*REG_SZ(%r3), %r29
2072#ifdef CONFIG_64BIT
2073	LDREG	8*REG_SZ(%r3), %r19
2074	LDREG	9*REG_SZ(%r3), %r20
2075	LDREG	10*REG_SZ(%r3), %r21
2076	LDREG	11*REG_SZ(%r3), %r22
2077	LDREG	12*REG_SZ(%r3), %r27
2078	LDREG	13*REG_SZ(%r3), %r31
2079#endif
2080	LDREG	1*REG_SZ(%r3), %r3
2081
2082	LDREGM	-FTRACE_FRAME_SIZE(%sp), %r1
2083	/* Adjust return point to jump back to beginning of traced function */
2084	ldo	-4(%r1), %r1
2085	bv,n	(%r1)
2086
2087ENDPROC_CFI(ftrace_caller)
2088
2089#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS
2090ENTRY_CFI(ftrace_regs_caller,caller,frame=FTRACE_FRAME_SIZE+PT_SZ_ALGN,
2091	CALLS,SAVE_RP,SAVE_SP)
2092ftrace_regs_caller:
2093	.global ftrace_regs_caller
2094
2095	ldo	-FTRACE_FRAME_SIZE(%sp), %r1
2096	STREG	%rp, -RP_OFFSET(%r1)
2097
2098	copy	%sp, %r1
2099	ldo	PT_SZ_ALGN(%sp), %sp
2100
2101	STREG	%rp, PT_GR2(%r1)
2102	STREG	%r3, PT_GR3(%r1)
2103	STREG	%r4, PT_GR4(%r1)
2104	STREG	%r5, PT_GR5(%r1)
2105	STREG	%r6, PT_GR6(%r1)
2106	STREG	%r7, PT_GR7(%r1)
2107	STREG	%r8, PT_GR8(%r1)
2108	STREG	%r9, PT_GR9(%r1)
2109	STREG   %r10, PT_GR10(%r1)
2110	STREG   %r11, PT_GR11(%r1)
2111	STREG   %r12, PT_GR12(%r1)
2112	STREG   %r13, PT_GR13(%r1)
2113	STREG   %r14, PT_GR14(%r1)
2114	STREG   %r15, PT_GR15(%r1)
2115	STREG   %r16, PT_GR16(%r1)
2116	STREG   %r17, PT_GR17(%r1)
2117	STREG   %r18, PT_GR18(%r1)
2118	STREG	%r19, PT_GR19(%r1)
2119	STREG	%r20, PT_GR20(%r1)
2120	STREG	%r21, PT_GR21(%r1)
2121	STREG	%r22, PT_GR22(%r1)
2122	STREG	%r23, PT_GR23(%r1)
2123	STREG	%r24, PT_GR24(%r1)
2124	STREG	%r25, PT_GR25(%r1)
2125	STREG	%r26, PT_GR26(%r1)
2126	STREG	%r27, PT_GR27(%r1)
2127	STREG	%r28, PT_GR28(%r1)
2128	STREG	%r29, PT_GR29(%r1)
2129	STREG	%r30, PT_GR30(%r1)
2130	STREG	%r31, PT_GR31(%r1)
2131	mfctl	%cr11, %r26
2132	STREG	%r26, PT_SAR(%r1)
2133
2134	copy	%rp, %r26
2135	LDREG	-FTRACE_FRAME_SIZE-PT_SZ_ALGN(%sp), %r25
2136	ldo	-8(%r25), %r25
2137	ldo	-FTRACE_FRAME_SIZE(%r1), %arg2
2138	b,l	ftrace_function_trampoline, %rp
2139	copy	%r1, %arg3 /* struct pt_regs */
2140
2141	ldo	-PT_SZ_ALGN(%sp), %r1
2142
2143	LDREG	PT_SAR(%r1), %rp
2144	mtctl	%rp, %cr11
2145
2146	LDREG	PT_GR2(%r1), %rp
2147	LDREG	PT_GR3(%r1), %r3
2148	LDREG	PT_GR4(%r1), %r4
2149	LDREG	PT_GR5(%r1), %r5
2150	LDREG	PT_GR6(%r1), %r6
2151	LDREG	PT_GR7(%r1), %r7
2152	LDREG	PT_GR8(%r1), %r8
2153	LDREG	PT_GR9(%r1), %r9
2154	LDREG   PT_GR10(%r1),%r10
2155	LDREG   PT_GR11(%r1),%r11
2156	LDREG   PT_GR12(%r1),%r12
2157	LDREG   PT_GR13(%r1),%r13
2158	LDREG   PT_GR14(%r1),%r14
2159	LDREG   PT_GR15(%r1),%r15
2160	LDREG   PT_GR16(%r1),%r16
2161	LDREG   PT_GR17(%r1),%r17
2162	LDREG   PT_GR18(%r1),%r18
2163	LDREG   PT_GR19(%r1),%r19
2164	LDREG   PT_GR20(%r1),%r20
2165	LDREG   PT_GR21(%r1),%r21
2166	LDREG   PT_GR22(%r1),%r22
2167	LDREG   PT_GR23(%r1),%r23
2168	LDREG   PT_GR24(%r1),%r24
2169	LDREG   PT_GR25(%r1),%r25
2170	LDREG   PT_GR26(%r1),%r26
2171	LDREG   PT_GR27(%r1),%r27
2172	LDREG   PT_GR28(%r1),%r28
2173	LDREG   PT_GR29(%r1),%r29
2174	LDREG   PT_GR30(%r1),%r30
2175	LDREG   PT_GR31(%r1),%r31
2176
2177	ldo	-PT_SZ_ALGN(%sp), %sp
2178	LDREGM	-FTRACE_FRAME_SIZE(%sp), %r1
2179	/* Adjust return point to jump back to beginning of traced function */
2180	ldo	-4(%r1), %r1
2181	bv,n	(%r1)
2182
2183ENDPROC_CFI(ftrace_regs_caller)
2184
2185#endif
2186#endif
2187
2188#ifdef CONFIG_FUNCTION_GRAPH_TRACER
2189	.align 8
2190ENTRY_CFI(return_to_handler, caller,frame=FRAME_SIZE)
2191	.export parisc_return_to_handler,data
2192parisc_return_to_handler:
2193	copy %r3,%r1
2194	STREG %r0,-RP_OFFSET(%sp)	/* store 0 as %rp */
2195	copy %sp,%r3
2196	STREGM %r1,FRAME_SIZE(%sp)
2197	STREG %ret0,8(%r3)
2198	STREG %ret1,16(%r3)
2199
2200#ifdef CONFIG_64BIT
2201	loadgp
2202#endif
2203
2204	/* call ftrace_return_to_handler(0) */
2205	.import ftrace_return_to_handler,code
2206	load32 ftrace_return_to_handler,%ret0
2207	load32 .Lftrace_ret,%r2
2208#ifdef CONFIG_64BIT
2209	ldo -16(%sp),%ret1		/* Reference param save area */
2210	bve	(%ret0)
2211#else
2212	bv	%r0(%ret0)
2213#endif
2214	ldi 0,%r26
2215.Lftrace_ret:
2216	copy %ret0,%rp
2217
2218	/* restore original return values */
2219	LDREG 8(%r3),%ret0
2220	LDREG 16(%r3),%ret1
2221
2222	/* return from function */
2223#ifdef CONFIG_64BIT
2224	bve	(%rp)
2225#else
2226	bv	%r0(%rp)
2227#endif
2228	LDREGM -FRAME_SIZE(%sp),%r3
2229ENDPROC_CFI(return_to_handler)
2230
2231#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
2232
2233#endif	/* CONFIG_FUNCTION_TRACER */
2234
2235#ifdef CONFIG_IRQSTACKS
2236/* void call_on_stack(unsigned long param1, void *func,
2237		      unsigned long new_stack) */
2238ENTRY_CFI(call_on_stack, FRAME=2*FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP)
2239ENTRY(_call_on_stack)
2240	copy	%sp, %r1
2241
2242	/* Regarding the HPPA calling conventions for function pointers,
2243	   we assume the PIC register is not changed across call.  For
2244	   CONFIG_64BIT, the argument pointer is left to point at the
2245	   argument region allocated for the call to call_on_stack. */
2246
2247	/* Switch to new stack.  We allocate two frames.  */
2248	ldo	2*FRAME_SIZE(%arg2), %sp
2249# ifdef CONFIG_64BIT
2250	/* Save previous stack pointer and return pointer in frame marker */
2251	STREG	%rp, -FRAME_SIZE-RP_OFFSET(%sp)
2252	/* Calls always use function descriptor */
2253	LDREG	16(%arg1), %arg1
2254	bve,l	(%arg1), %rp
2255	STREG	%r1, -FRAME_SIZE-REG_SZ(%sp)
2256	LDREG	-FRAME_SIZE-RP_OFFSET(%sp), %rp
2257	bve	(%rp)
2258	LDREG	-FRAME_SIZE-REG_SZ(%sp), %sp
2259# else
2260	/* Save previous stack pointer and return pointer in frame marker */
2261	STREG	%r1, -FRAME_SIZE-REG_SZ(%sp)
2262	STREG	%rp, -FRAME_SIZE-RP_OFFSET(%sp)
2263	/* Calls use function descriptor if PLABEL bit is set */
2264	bb,>=,n	%arg1, 30, 1f
2265	depwi	0,31,2, %arg1
2266	LDREG	0(%arg1), %arg1
22671:
2268	be,l	0(%sr4,%arg1), %sr0, %r31
2269	copy	%r31, %rp
2270	LDREG	-FRAME_SIZE-RP_OFFSET(%sp), %rp
2271	bv	(%rp)
2272	LDREG	-FRAME_SIZE-REG_SZ(%sp), %sp
2273# endif /* CONFIG_64BIT */
2274ENDPROC_CFI(call_on_stack)
2275#endif /* CONFIG_IRQSTACKS */
2276
2277ENTRY_CFI(get_register)
2278	/*
2279	 * get_register is used by the non access tlb miss handlers to
2280	 * copy the value of the general register specified in r8 into
2281	 * r1. This routine can't be used for shadowed registers, since
2282	 * the rfir will restore the original value. So, for the shadowed
2283	 * registers we put a -1 into r1 to indicate that the register
2284	 * should not be used (the register being copied could also have
2285	 * a -1 in it, but that is OK, it just means that we will have
2286	 * to use the slow path instead).
2287	 */
2288	blr     %r8,%r0
2289	nop
2290	bv      %r0(%r25)    /* r0 */
2291	copy    %r0,%r1
2292	bv      %r0(%r25)    /* r1 - shadowed */
2293	ldi     -1,%r1
2294	bv      %r0(%r25)    /* r2 */
2295	copy    %r2,%r1
2296	bv      %r0(%r25)    /* r3 */
2297	copy    %r3,%r1
2298	bv      %r0(%r25)    /* r4 */
2299	copy    %r4,%r1
2300	bv      %r0(%r25)    /* r5 */
2301	copy    %r5,%r1
2302	bv      %r0(%r25)    /* r6 */
2303	copy    %r6,%r1
2304	bv      %r0(%r25)    /* r7 */
2305	copy    %r7,%r1
2306	bv      %r0(%r25)    /* r8 - shadowed */
2307	ldi     -1,%r1
2308	bv      %r0(%r25)    /* r9 - shadowed */
2309	ldi     -1,%r1
2310	bv      %r0(%r25)    /* r10 */
2311	copy    %r10,%r1
2312	bv      %r0(%r25)    /* r11 */
2313	copy    %r11,%r1
2314	bv      %r0(%r25)    /* r12 */
2315	copy    %r12,%r1
2316	bv      %r0(%r25)    /* r13 */
2317	copy    %r13,%r1
2318	bv      %r0(%r25)    /* r14 */
2319	copy    %r14,%r1
2320	bv      %r0(%r25)    /* r15 */
2321	copy    %r15,%r1
2322	bv      %r0(%r25)    /* r16 - shadowed */
2323	ldi     -1,%r1
2324	bv      %r0(%r25)    /* r17 - shadowed */
2325	ldi     -1,%r1
2326	bv      %r0(%r25)    /* r18 */
2327	copy    %r18,%r1
2328	bv      %r0(%r25)    /* r19 */
2329	copy    %r19,%r1
2330	bv      %r0(%r25)    /* r20 */
2331	copy    %r20,%r1
2332	bv      %r0(%r25)    /* r21 */
2333	copy    %r21,%r1
2334	bv      %r0(%r25)    /* r22 */
2335	copy    %r22,%r1
2336	bv      %r0(%r25)    /* r23 */
2337	copy    %r23,%r1
2338	bv      %r0(%r25)    /* r24 - shadowed */
2339	ldi     -1,%r1
2340	bv      %r0(%r25)    /* r25 - shadowed */
2341	ldi     -1,%r1
2342	bv      %r0(%r25)    /* r26 */
2343	copy    %r26,%r1
2344	bv      %r0(%r25)    /* r27 */
2345	copy    %r27,%r1
2346	bv      %r0(%r25)    /* r28 */
2347	copy    %r28,%r1
2348	bv      %r0(%r25)    /* r29 */
2349	copy    %r29,%r1
2350	bv      %r0(%r25)    /* r30 */
2351	copy    %r30,%r1
2352	bv      %r0(%r25)    /* r31 */
2353	copy    %r31,%r1
2354ENDPROC_CFI(get_register)
2355
2356
2357ENTRY_CFI(set_register)
2358	/*
2359	 * set_register is used by the non access tlb miss handlers to
2360	 * copy the value of r1 into the general register specified in
2361	 * r8.
2362	 */
2363	blr     %r8,%r0
2364	nop
2365	bv      %r0(%r25)    /* r0 (silly, but it is a place holder) */
2366	copy    %r1,%r0
2367	bv      %r0(%r25)    /* r1 */
2368	copy    %r1,%r1
2369	bv      %r0(%r25)    /* r2 */
2370	copy    %r1,%r2
2371	bv      %r0(%r25)    /* r3 */
2372	copy    %r1,%r3
2373	bv      %r0(%r25)    /* r4 */
2374	copy    %r1,%r4
2375	bv      %r0(%r25)    /* r5 */
2376	copy    %r1,%r5
2377	bv      %r0(%r25)    /* r6 */
2378	copy    %r1,%r6
2379	bv      %r0(%r25)    /* r7 */
2380	copy    %r1,%r7
2381	bv      %r0(%r25)    /* r8 */
2382	copy    %r1,%r8
2383	bv      %r0(%r25)    /* r9 */
2384	copy    %r1,%r9
2385	bv      %r0(%r25)    /* r10 */
2386	copy    %r1,%r10
2387	bv      %r0(%r25)    /* r11 */
2388	copy    %r1,%r11
2389	bv      %r0(%r25)    /* r12 */
2390	copy    %r1,%r12
2391	bv      %r0(%r25)    /* r13 */
2392	copy    %r1,%r13
2393	bv      %r0(%r25)    /* r14 */
2394	copy    %r1,%r14
2395	bv      %r0(%r25)    /* r15 */
2396	copy    %r1,%r15
2397	bv      %r0(%r25)    /* r16 */
2398	copy    %r1,%r16
2399	bv      %r0(%r25)    /* r17 */
2400	copy    %r1,%r17
2401	bv      %r0(%r25)    /* r18 */
2402	copy    %r1,%r18
2403	bv      %r0(%r25)    /* r19 */
2404	copy    %r1,%r19
2405	bv      %r0(%r25)    /* r20 */
2406	copy    %r1,%r20
2407	bv      %r0(%r25)    /* r21 */
2408	copy    %r1,%r21
2409	bv      %r0(%r25)    /* r22 */
2410	copy    %r1,%r22
2411	bv      %r0(%r25)    /* r23 */
2412	copy    %r1,%r23
2413	bv      %r0(%r25)    /* r24 */
2414	copy    %r1,%r24
2415	bv      %r0(%r25)    /* r25 */
2416	copy    %r1,%r25
2417	bv      %r0(%r25)    /* r26 */
2418	copy    %r1,%r26
2419	bv      %r0(%r25)    /* r27 */
2420	copy    %r1,%r27
2421	bv      %r0(%r25)    /* r28 */
2422	copy    %r1,%r28
2423	bv      %r0(%r25)    /* r29 */
2424	copy    %r1,%r29
2425	bv      %r0(%r25)    /* r30 */
2426	copy    %r1,%r30
2427	bv      %r0(%r25)    /* r31 */
2428	copy    %r1,%r31
2429ENDPROC_CFI(set_register)
2430
2431