xref: /openbmc/linux/arch/parisc/kernel/entry.S (revision f20c7d91)
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	LDCW		0(\tmp),\tmp1
458	b		\fault
459	stw		\spc,0(\tmp)
46099:	ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
461#endif
4622:	LDREG		0(\ptp),\pte
463	bb,>=,n		\pte,_PAGE_PRESENT_BIT,\fault
4643:
465	.endm
466
467	/* Release pa_tlb_lock lock without reloading lock address. */
468	.macro		tlb_unlock0	spc,tmp,tmp1
469#ifdef CONFIG_SMP
47098:	or,COND(=)	%r0,\spc,%r0
471	LDCW		0(\tmp),\tmp1
472	or,COND(=)	%r0,\spc,%r0
473	stw		\spc,0(\tmp)
47499:	ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
475#endif
476	.endm
477
478	/* Release pa_tlb_lock lock. */
479	.macro		tlb_unlock1	spc,tmp,tmp1
480#ifdef CONFIG_SMP
48198:	load_pa_tlb_lock \tmp
48299:	ALTERNATIVE(98b, 99b, ALT_COND_NO_SMP, INSN_NOP)
483	tlb_unlock0	\spc,\tmp,\tmp1
484#endif
485	.endm
486
487	/* Set the _PAGE_ACCESSED bit of the PTE.  Be clever and
488	 * don't needlessly dirty the cache line if it was already set */
489	.macro		update_accessed	ptp,pte,tmp,tmp1
490	ldi		_PAGE_ACCESSED,\tmp1
491	or		\tmp1,\pte,\tmp
492	and,COND(<>)	\tmp1,\pte,%r0
493	STREG		\tmp,0(\ptp)
494	.endm
495
496	/* Set the dirty bit (and accessed bit).  No need to be
497	 * clever, this is only used from the dirty fault */
498	.macro		update_dirty	ptp,pte,tmp
499	ldi		_PAGE_ACCESSED|_PAGE_DIRTY,\tmp
500	or		\tmp,\pte,\pte
501	STREG		\pte,0(\ptp)
502	.endm
503
504	/* We have (depending on the page size):
505	 * - 38 to 52-bit Physical Page Number
506	 * - 12 to 26-bit page offset
507	 */
508	/* bitshift difference between a PFN (based on kernel's PAGE_SIZE)
509	 * to a CPU TLB 4k PFN (4k => 12 bits to shift) */
510	#define PAGE_ADD_SHIFT		(PAGE_SHIFT-12)
511	#define PAGE_ADD_HUGE_SHIFT	(REAL_HPAGE_SHIFT-12)
512
513	/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
514	.macro		convert_for_tlb_insert20 pte,tmp
515#ifdef CONFIG_HUGETLB_PAGE
516	copy		\pte,\tmp
517	extrd,u		\tmp,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
518				64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
519
520	depdi		_PAGE_SIZE_ENCODING_DEFAULT,63,\
521				(63-58)+PAGE_ADD_SHIFT,\pte
522	extrd,u,*=	\tmp,_PAGE_HPAGE_BIT+32,1,%r0
523	depdi		_HUGE_PAGE_SIZE_ENCODING_DEFAULT,63,\
524				(63-58)+PAGE_ADD_HUGE_SHIFT,\pte
525#else /* Huge pages disabled */
526	extrd,u		\pte,(63-ASM_PFN_PTE_SHIFT)+(63-58)+PAGE_ADD_SHIFT,\
527				64-PAGE_SHIFT-PAGE_ADD_SHIFT,\pte
528	depdi		_PAGE_SIZE_ENCODING_DEFAULT,63,\
529				(63-58)+PAGE_ADD_SHIFT,\pte
530#endif
531	.endm
532
533	/* Convert the pte and prot to tlb insertion values.  How
534	 * this happens is quite subtle, read below */
535	.macro		make_insert_tlb	spc,pte,prot,tmp
536	space_to_prot   \spc \prot        /* create prot id from space */
537	/* The following is the real subtlety.  This is depositing
538	 * T <-> _PAGE_REFTRAP
539	 * D <-> _PAGE_DIRTY
540	 * B <-> _PAGE_DMB (memory break)
541	 *
542	 * Then incredible subtlety: The access rights are
543	 * _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE
544	 * See 3-14 of the parisc 2.0 manual
545	 *
546	 * Finally, _PAGE_READ goes in the top bit of PL1 (so we
547	 * trigger an access rights trap in user space if the user
548	 * tries to read an unreadable page */
549	depd            \pte,8,7,\prot
550
551	/* PAGE_USER indicates the page can be read with user privileges,
552	 * so deposit X1|11 to PL1|PL2 (remember the upper bit of PL1
553	 * contains _PAGE_READ) */
554	extrd,u,*=      \pte,_PAGE_USER_BIT+32,1,%r0
555	depdi		7,11,3,\prot
556	/* If we're a gateway page, drop PL2 back to zero for promotion
557	 * to kernel privilege (so we can execute the page as kernel).
558	 * Any privilege promotion page always denys read and write */
559	extrd,u,*= 	\pte,_PAGE_GATEWAY_BIT+32,1,%r0
560	depd		%r0,11,2,\prot	/* If Gateway, Set PL2 to 0 */
561
562	/* Enforce uncacheable pages.
563	 * This should ONLY be use for MMIO on PA 2.0 machines.
564	 * Memory/DMA is cache coherent on all PA2.0 machines we support
565	 * (that means T-class is NOT supported) and the memory controllers
566	 * on most of those machines only handles cache transactions.
567	 */
568	extrd,u,*=	\pte,_PAGE_NO_CACHE_BIT+32,1,%r0
569	depdi		1,12,1,\prot
570
571	/* Drop prot bits and convert to page addr for iitlbt and idtlbt */
572	convert_for_tlb_insert20 \pte \tmp
573	.endm
574
575	/* Identical macro to make_insert_tlb above, except it
576	 * makes the tlb entry for the differently formatted pa11
577	 * insertion instructions */
578	.macro		make_insert_tlb_11	spc,pte,prot
579	zdep		\spc,30,15,\prot
580	dep		\pte,8,7,\prot
581	extru,=		\pte,_PAGE_NO_CACHE_BIT,1,%r0
582	depi		1,12,1,\prot
583	extru,=         \pte,_PAGE_USER_BIT,1,%r0
584	depi		7,11,3,\prot   /* Set for user space (1 rsvd for read) */
585	extru,= 	\pte,_PAGE_GATEWAY_BIT,1,%r0
586	depi		0,11,2,\prot	/* If Gateway, Set PL2 to 0 */
587
588	/* Get rid of prot bits and convert to page addr for iitlba */
589
590	depi		0,31,ASM_PFN_PTE_SHIFT,\pte
591	SHRREG		\pte,(ASM_PFN_PTE_SHIFT-(31-26)),\pte
592	.endm
593
594	/* This is for ILP32 PA2.0 only.  The TLB insertion needs
595	 * to extend into I/O space if the address is 0xfXXXXXXX
596	 * so we extend the f's into the top word of the pte in
597	 * this case */
598	.macro		f_extend	pte,tmp
599	extrd,s		\pte,42,4,\tmp
600	addi,<>		1,\tmp,%r0
601	extrd,s		\pte,63,25,\pte
602	.endm
603
604	/* The alias region is an 8MB aligned 16MB to do clear and
605	 * copy user pages at addresses congruent with the user
606	 * virtual address.
607	 *
608	 * To use the alias page, you set %r26 up with the to TLB
609	 * entry (identifying the physical page) and %r23 up with
610	 * the from tlb entry (or nothing if only a to entry---for
611	 * clear_user_page_asm) */
612	.macro		do_alias	spc,tmp,tmp1,va,pte,prot,fault,patype
613	cmpib,COND(<>),n 0,\spc,\fault
614	ldil		L%(TMPALIAS_MAP_START),\tmp
615#if defined(CONFIG_64BIT) && (TMPALIAS_MAP_START >= 0x80000000)
616	/* on LP64, ldi will sign extend into the upper 32 bits,
617	 * which is behaviour we don't want */
618	depdi		0,31,32,\tmp
619#endif
620	copy		\va,\tmp1
621	depi		0,31,23,\tmp1
622	cmpb,COND(<>),n	\tmp,\tmp1,\fault
623	mfctl		%cr19,\tmp	/* iir */
624	/* get the opcode (first six bits) into \tmp */
625	extrw,u		\tmp,5,6,\tmp
626	/*
627	 * Only setting the T bit prevents data cache movein
628	 * Setting access rights to zero prevents instruction cache movein
629	 *
630	 * Note subtlety here: _PAGE_GATEWAY, _PAGE_EXEC and _PAGE_WRITE go
631	 * to type field and _PAGE_READ goes to top bit of PL1
632	 */
633	ldi		(_PAGE_REFTRAP|_PAGE_READ|_PAGE_WRITE),\prot
634	/*
635	 * so if the opcode is one (i.e. this is a memory management
636	 * instruction) nullify the next load so \prot is only T.
637	 * Otherwise this is a normal data operation
638	 */
639	cmpiclr,=	0x01,\tmp,%r0
640	ldi		(_PAGE_DIRTY|_PAGE_READ|_PAGE_WRITE),\prot
641.ifc \patype,20
642	depd,z		\prot,8,7,\prot
643.else
644.ifc \patype,11
645	depw,z		\prot,8,7,\prot
646.else
647	.error "undefined PA type to do_alias"
648.endif
649.endif
650	/*
651	 * OK, it is in the temp alias region, check whether "from" or "to".
652	 * Check "subtle" note in pacache.S re: r23/r26.
653	 */
654#ifdef CONFIG_64BIT
655	extrd,u,*=	\va,41,1,%r0
656#else
657	extrw,u,=	\va,9,1,%r0
658#endif
659	or,COND(tr)	%r23,%r0,\pte
660	or		%r26,%r0,\pte
661	.endm
662
663
664	/*
665	 * Fault_vectors are architecturally required to be aligned on a 2K
666	 * boundary
667	 */
668
669	.section .text.hot
670	.align 2048
671
672ENTRY(fault_vector_20)
673	/* First vector is invalid (0) */
674	.ascii	"cows can fly"
675	.byte 0
676	.align 32
677
678	hpmc		 1
679	def		 2
680	def		 3
681	extint		 4
682	def		 5
683	itlb_20		 PARISC_ITLB_TRAP
684	def		 7
685	def		 8
686	def              9
687	def		10
688	def		11
689	def		12
690	def		13
691	def		14
692	dtlb_20		15
693	naitlb_20	16
694	nadtlb_20	17
695	def		18
696	def		19
697	dbit_20		20
698	def		21
699	def		22
700	def		23
701	def		24
702	def		25
703	def		26
704	def		27
705	def		28
706	def		29
707	def		30
708	def		31
709END(fault_vector_20)
710
711#ifndef CONFIG_64BIT
712
713	.align 2048
714
715ENTRY(fault_vector_11)
716	/* First vector is invalid (0) */
717	.ascii	"cows can fly"
718	.byte 0
719	.align 32
720
721	hpmc		 1
722	def		 2
723	def		 3
724	extint		 4
725	def		 5
726	itlb_11		 PARISC_ITLB_TRAP
727	def		 7
728	def		 8
729	def              9
730	def		10
731	def		11
732	def		12
733	def		13
734	def		14
735	dtlb_11		15
736	naitlb_11	16
737	nadtlb_11	17
738	def		18
739	def		19
740	dbit_11		20
741	def		21
742	def		22
743	def		23
744	def		24
745	def		25
746	def		26
747	def		27
748	def		28
749	def		29
750	def		30
751	def		31
752END(fault_vector_11)
753
754#endif
755	/* Fault vector is separately protected and *must* be on its own page */
756	.align		PAGE_SIZE
757
758	.import		handle_interruption,code
759	.import		do_cpu_irq_mask,code
760
761	/*
762	 * Child Returns here
763	 *
764	 * copy_thread moved args into task save area.
765	 */
766
767ENTRY(ret_from_kernel_thread)
768	/* Call schedule_tail first though */
769	BL	schedule_tail, %r2
770	nop
771
772	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
773	LDREG	TASK_PT_GR25(%r1), %r26
774#ifdef CONFIG_64BIT
775	LDREG	TASK_PT_GR27(%r1), %r27
776#endif
777	LDREG	TASK_PT_GR26(%r1), %r1
778	ble	0(%sr7, %r1)
779	copy	%r31, %r2
780	b	finish_child_return
781	nop
782END(ret_from_kernel_thread)
783
784
785	/*
786	 * struct task_struct *_switch_to(struct task_struct *prev,
787	 *	struct task_struct *next)
788	 *
789	 * switch kernel stacks and return prev */
790ENTRY_CFI(_switch_to)
791	STREG	 %r2, -RP_OFFSET(%r30)
792
793	callee_save_float
794	callee_save
795
796	load32	_switch_to_ret, %r2
797
798	STREG	%r2, TASK_PT_KPC(%r26)
799	LDREG	TASK_PT_KPC(%r25), %r2
800
801	STREG	%r30, TASK_PT_KSP(%r26)
802	LDREG	TASK_PT_KSP(%r25), %r30
803	LDREG	TASK_THREAD_INFO(%r25), %r25
804	bv	%r0(%r2)
805	mtctl   %r25,%cr30
806
807ENTRY(_switch_to_ret)
808	mtctl	%r0, %cr0		/* Needed for single stepping */
809	callee_rest
810	callee_rest_float
811
812	LDREG	-RP_OFFSET(%r30), %r2
813	bv	%r0(%r2)
814	copy	%r26, %r28
815ENDPROC_CFI(_switch_to)
816
817	/*
818	 * Common rfi return path for interruptions, kernel execve, and
819	 * sys_rt_sigreturn (sometimes).  The sys_rt_sigreturn syscall will
820	 * return via this path if the signal was received when the process
821	 * was running; if the process was blocked on a syscall then the
822	 * normal syscall_exit path is used.  All syscalls for traced
823	 * proceses exit via intr_restore.
824	 *
825	 * XXX If any syscalls that change a processes space id ever exit
826	 * this way, then we will need to copy %sr3 in to PT_SR[3..7], and
827	 * adjust IASQ[0..1].
828	 *
829	 */
830
831	.align	PAGE_SIZE
832
833ENTRY_CFI(syscall_exit_rfi)
834	mfctl   %cr30,%r16
835	LDREG	TI_TASK(%r16), %r16	/* thread_info -> task_struct */
836	ldo	TASK_REGS(%r16),%r16
837	/* Force iaoq to userspace, as the user has had access to our current
838	 * context via sigcontext. Also Filter the PSW for the same reason.
839	 */
840	LDREG	PT_IAOQ0(%r16),%r19
841	depi	3,31,2,%r19
842	STREG	%r19,PT_IAOQ0(%r16)
843	LDREG	PT_IAOQ1(%r16),%r19
844	depi	3,31,2,%r19
845	STREG	%r19,PT_IAOQ1(%r16)
846	LDREG   PT_PSW(%r16),%r19
847	load32	USER_PSW_MASK,%r1
848#ifdef CONFIG_64BIT
849	load32	USER_PSW_HI_MASK,%r20
850	depd    %r20,31,32,%r1
851#endif
852	and     %r19,%r1,%r19 /* Mask out bits that user shouldn't play with */
853	load32	USER_PSW,%r1
854	or      %r19,%r1,%r19 /* Make sure default USER_PSW bits are set */
855	STREG   %r19,PT_PSW(%r16)
856
857	/*
858	 * If we aren't being traced, we never saved space registers
859	 * (we don't store them in the sigcontext), so set them
860	 * to "proper" values now (otherwise we'll wind up restoring
861	 * whatever was last stored in the task structure, which might
862	 * be inconsistent if an interrupt occurred while on the gateway
863	 * page). Note that we may be "trashing" values the user put in
864	 * them, but we don't support the user changing them.
865	 */
866
867	STREG   %r0,PT_SR2(%r16)
868	mfsp    %sr3,%r19
869	STREG   %r19,PT_SR0(%r16)
870	STREG   %r19,PT_SR1(%r16)
871	STREG   %r19,PT_SR3(%r16)
872	STREG   %r19,PT_SR4(%r16)
873	STREG   %r19,PT_SR5(%r16)
874	STREG   %r19,PT_SR6(%r16)
875	STREG   %r19,PT_SR7(%r16)
876
877ENTRY(intr_return)
878	/* check for reschedule */
879	mfctl   %cr30,%r1
880	LDREG   TI_FLAGS(%r1),%r19	/* sched.h: TIF_NEED_RESCHED */
881	bb,<,n	%r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */
882
883	.import do_notify_resume,code
884intr_check_sig:
885	/* As above */
886	mfctl   %cr30,%r1
887	LDREG	TI_FLAGS(%r1),%r19
888	ldi	(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME), %r20
889	and,COND(<>)	%r19, %r20, %r0
890	b,n	intr_restore	/* skip past if we've nothing to do */
891
892	/* This check is critical to having LWS
893	 * working. The IASQ is zero on the gateway
894	 * page and we cannot deliver any signals until
895	 * we get off the gateway page.
896	 *
897	 * Only do signals if we are returning to user space
898	 */
899	LDREG	PT_IASQ0(%r16), %r20
900	cmpib,COND(=),n LINUX_GATEWAY_SPACE, %r20, intr_restore /* backward */
901	LDREG	PT_IASQ1(%r16), %r20
902	cmpib,COND(=),n LINUX_GATEWAY_SPACE, %r20, intr_restore /* backward */
903
904	/* NOTE: We need to enable interrupts if we have to deliver
905	 * signals. We used to do this earlier but it caused kernel
906	 * stack overflows. */
907	ssm     PSW_SM_I, %r0
908
909	copy	%r0, %r25			/* long in_syscall = 0 */
910#ifdef CONFIG_64BIT
911	ldo	-16(%r30),%r29			/* Reference param save area */
912#endif
913
914	BL	do_notify_resume,%r2
915	copy	%r16, %r26			/* struct pt_regs *regs */
916
917	b,n	intr_check_sig
918
919intr_restore:
920	copy            %r16,%r29
921	ldo             PT_FR31(%r29),%r1
922	rest_fp         %r1
923	rest_general    %r29
924
925	/* inverse of virt_map */
926	pcxt_ssm_bug
927	rsm             PSW_SM_QUIET,%r0	/* prepare for rfi */
928	tophys_r1       %r29
929
930	/* Restore space id's and special cr's from PT_REGS
931	 * structure pointed to by r29
932	 */
933	rest_specials	%r29
934
935	/* IMPORTANT: rest_stack restores r29 last (we are using it)!
936	 * It also restores r1 and r30.
937	 */
938	rest_stack
939
940	rfi
941	nop
942
943#ifndef CONFIG_PREEMPTION
944# define intr_do_preempt	intr_restore
945#endif /* !CONFIG_PREEMPTION */
946
947	.import schedule,code
948intr_do_resched:
949	/* Only call schedule on return to userspace. If we're returning
950	 * to kernel space, we may schedule if CONFIG_PREEMPTION, otherwise
951	 * we jump back to intr_restore.
952	 */
953	LDREG	PT_IASQ0(%r16), %r20
954	cmpib,COND(=)	0, %r20, intr_do_preempt
955	nop
956	LDREG	PT_IASQ1(%r16), %r20
957	cmpib,COND(=)	0, %r20, intr_do_preempt
958	nop
959
960	/* NOTE: We need to enable interrupts if we schedule.  We used
961	 * to do this earlier but it caused kernel stack overflows. */
962	ssm     PSW_SM_I, %r0
963
964#ifdef CONFIG_64BIT
965	ldo	-16(%r30),%r29		/* Reference param save area */
966#endif
967
968	ldil	L%intr_check_sig, %r2
969#ifndef CONFIG_64BIT
970	b	schedule
971#else
972	load32	schedule, %r20
973	bv	%r0(%r20)
974#endif
975	ldo	R%intr_check_sig(%r2), %r2
976
977	/* preempt the current task on returning to kernel
978	 * mode from an interrupt, iff need_resched is set,
979	 * and preempt_count is 0. otherwise, we continue on
980	 * our merry way back to the current running task.
981	 */
982#ifdef CONFIG_PREEMPTION
983	.import preempt_schedule_irq,code
984intr_do_preempt:
985	rsm	PSW_SM_I, %r0		/* disable interrupts */
986
987	/* current_thread_info()->preempt_count */
988	mfctl	%cr30, %r1
989	LDREG	TI_PRE_COUNT(%r1), %r19
990	cmpib,COND(<>)	0, %r19, intr_restore	/* if preempt_count > 0 */
991	nop				/* prev insn branched backwards */
992
993	/* check if we interrupted a critical path */
994	LDREG	PT_PSW(%r16), %r20
995	bb,<,n	%r20, 31 - PSW_SM_I, intr_restore
996	nop
997
998	BL	preempt_schedule_irq, %r2
999	nop
1000
1001	b,n	intr_restore		/* ssm PSW_SM_I done by intr_restore */
1002#endif /* CONFIG_PREEMPTION */
1003
1004	/*
1005	 * External interrupts.
1006	 */
1007
1008intr_extint:
1009	cmpib,COND(=),n 0,%r16,1f
1010
1011	get_stack_use_cr30
1012	b,n 2f
1013
10141:
1015	get_stack_use_r30
10162:
1017	save_specials	%r29
1018	virt_map
1019	save_general	%r29
1020
1021	ldo	PT_FR0(%r29), %r24
1022	save_fp	%r24
1023
1024	loadgp
1025
1026	copy	%r29, %r26	/* arg0 is pt_regs */
1027	copy	%r29, %r16	/* save pt_regs */
1028
1029	ldil	L%intr_return, %r2
1030
1031#ifdef CONFIG_64BIT
1032	ldo	-16(%r30),%r29	/* Reference param save area */
1033#endif
1034
1035	b	do_cpu_irq_mask
1036	ldo	R%intr_return(%r2), %r2	/* return to intr_return, not here */
1037ENDPROC_CFI(syscall_exit_rfi)
1038
1039
1040	/* Generic interruptions (illegal insn, unaligned, page fault, etc) */
1041
1042ENTRY_CFI(intr_save)		/* for os_hpmc */
1043	mfsp    %sr7,%r16
1044	cmpib,COND(=),n 0,%r16,1f
1045	get_stack_use_cr30
1046	b	2f
1047	copy    %r8,%r26
1048
10491:
1050	get_stack_use_r30
1051	copy    %r8,%r26
1052
10532:
1054	save_specials	%r29
1055
1056	/* If this trap is a itlb miss, skip saving/adjusting isr/ior */
1057	cmpib,COND(=),n        PARISC_ITLB_TRAP,%r26,skip_save_ior
1058
1059
1060	mfctl           %isr, %r16
1061	nop		/* serialize mfctl on PA 2.0 to avoid 4 cycle penalty */
1062	mfctl           %ior, %r17
1063
1064
1065#ifdef CONFIG_64BIT
1066	/*
1067	 * If the interrupted code was running with W bit off (32 bit),
1068	 * clear the b bits (bits 0 & 1) in the ior.
1069	 * save_specials left ipsw value in r8 for us to test.
1070	 */
1071	extrd,u,*<>     %r8,PSW_W_BIT,1,%r0
1072	depdi           0,1,2,%r17
1073
1074	/* adjust isr/ior: get high bits from isr and deposit in ior */
1075	space_adjust	%r16,%r17,%r1
1076#endif
1077	STREG           %r16, PT_ISR(%r29)
1078	STREG           %r17, PT_IOR(%r29)
1079
1080#if 0 && defined(CONFIG_64BIT)
1081	/* Revisit when we have 64-bit code above 4Gb */
1082	b,n		intr_save2
1083
1084skip_save_ior:
1085	/* We have a itlb miss, and when executing code above 4 Gb on ILP64, we
1086	 * need to adjust iasq/iaoq here in the same way we adjusted isr/ior
1087	 * above.
1088	 */
1089	extrd,u,*	%r8,PSW_W_BIT,1,%r1
1090	cmpib,COND(=),n	1,%r1,intr_save2
1091	LDREG		PT_IASQ0(%r29), %r16
1092	LDREG		PT_IAOQ0(%r29), %r17
1093	/* adjust iasq/iaoq */
1094	space_adjust	%r16,%r17,%r1
1095	STREG           %r16, PT_IASQ0(%r29)
1096	STREG           %r17, PT_IAOQ0(%r29)
1097#else
1098skip_save_ior:
1099#endif
1100
1101intr_save2:
1102	virt_map
1103	save_general	%r29
1104
1105	ldo		PT_FR0(%r29), %r25
1106	save_fp		%r25
1107
1108	loadgp
1109
1110	copy		%r29, %r25	/* arg1 is pt_regs */
1111#ifdef CONFIG_64BIT
1112	ldo		-16(%r30),%r29	/* Reference param save area */
1113#endif
1114
1115	ldil		L%intr_check_sig, %r2
1116	copy		%r25, %r16	/* save pt_regs */
1117
1118	b		handle_interruption
1119	ldo		R%intr_check_sig(%r2), %r2
1120ENDPROC_CFI(intr_save)
1121
1122
1123	/*
1124	 * Note for all tlb miss handlers:
1125	 *
1126	 * cr24 contains a pointer to the kernel address space
1127	 * page directory.
1128	 *
1129	 * cr25 contains a pointer to the current user address
1130	 * space page directory.
1131	 *
1132	 * sr3 will contain the space id of the user address space
1133	 * of the current running thread while that thread is
1134	 * running in the kernel.
1135	 */
1136
1137	/*
1138	 * register number allocations.  Note that these are all
1139	 * in the shadowed registers
1140	 */
1141
1142	t0 = r1		/* temporary register 0 */
1143	va = r8		/* virtual address for which the trap occurred */
1144	t1 = r9		/* temporary register 1 */
1145	pte  = r16	/* pte/phys page # */
1146	prot = r17	/* prot bits */
1147	spc  = r24	/* space for which the trap occurred */
1148	ptp = r25	/* page directory/page table pointer */
1149
1150#ifdef CONFIG_64BIT
1151
1152dtlb_miss_20w:
1153	space_adjust	spc,va,t0
1154	get_pgd		spc,ptp
1155	space_check	spc,t0,dtlb_fault
1156
1157	L3_ptep		ptp,pte,t0,va,dtlb_check_alias_20w
1158
1159	tlb_lock	spc,ptp,pte,t0,t1,dtlb_check_alias_20w
1160	update_accessed	ptp,pte,t0,t1
1161
1162	make_insert_tlb	spc,pte,prot,t1
1163
1164	idtlbt          pte,prot
1165
1166	tlb_unlock1	spc,t0,t1
1167	rfir
1168	nop
1169
1170dtlb_check_alias_20w:
1171	do_alias	spc,t0,t1,va,pte,prot,dtlb_fault,20
1172
1173	idtlbt          pte,prot
1174
1175	rfir
1176	nop
1177
1178nadtlb_miss_20w:
1179	space_adjust	spc,va,t0
1180	get_pgd		spc,ptp
1181	space_check	spc,t0,nadtlb_fault
1182
1183	L3_ptep		ptp,pte,t0,va,nadtlb_check_alias_20w
1184
1185	tlb_lock	spc,ptp,pte,t0,t1,nadtlb_check_alias_20w
1186	update_accessed	ptp,pte,t0,t1
1187
1188	make_insert_tlb	spc,pte,prot,t1
1189
1190	idtlbt          pte,prot
1191
1192	tlb_unlock1	spc,t0,t1
1193	rfir
1194	nop
1195
1196nadtlb_check_alias_20w:
1197	do_alias	spc,t0,t1,va,pte,prot,nadtlb_emulate,20
1198
1199	idtlbt          pte,prot
1200
1201	rfir
1202	nop
1203
1204#else
1205
1206dtlb_miss_11:
1207	get_pgd		spc,ptp
1208
1209	space_check	spc,t0,dtlb_fault
1210
1211	L2_ptep		ptp,pte,t0,va,dtlb_check_alias_11
1212
1213	tlb_lock	spc,ptp,pte,t0,t1,dtlb_check_alias_11
1214	update_accessed	ptp,pte,t0,t1
1215
1216	make_insert_tlb_11	spc,pte,prot
1217
1218	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1219	mtsp		spc,%sr1
1220
1221	idtlba		pte,(%sr1,va)
1222	idtlbp		prot,(%sr1,va)
1223
1224	mtsp		t1, %sr1	/* Restore sr1 */
1225
1226	tlb_unlock1	spc,t0,t1
1227	rfir
1228	nop
1229
1230dtlb_check_alias_11:
1231	do_alias	spc,t0,t1,va,pte,prot,dtlb_fault,11
1232
1233	idtlba          pte,(va)
1234	idtlbp          prot,(va)
1235
1236	rfir
1237	nop
1238
1239nadtlb_miss_11:
1240	get_pgd		spc,ptp
1241
1242	space_check	spc,t0,nadtlb_fault
1243
1244	L2_ptep		ptp,pte,t0,va,nadtlb_check_alias_11
1245
1246	tlb_lock	spc,ptp,pte,t0,t1,nadtlb_check_alias_11
1247	update_accessed	ptp,pte,t0,t1
1248
1249	make_insert_tlb_11	spc,pte,prot
1250
1251	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1252	mtsp		spc,%sr1
1253
1254	idtlba		pte,(%sr1,va)
1255	idtlbp		prot,(%sr1,va)
1256
1257	mtsp		t1, %sr1	/* Restore sr1 */
1258
1259	tlb_unlock1	spc,t0,t1
1260	rfir
1261	nop
1262
1263nadtlb_check_alias_11:
1264	do_alias	spc,t0,t1,va,pte,prot,nadtlb_emulate,11
1265
1266	idtlba          pte,(va)
1267	idtlbp          prot,(va)
1268
1269	rfir
1270	nop
1271
1272dtlb_miss_20:
1273	space_adjust	spc,va,t0
1274	get_pgd		spc,ptp
1275	space_check	spc,t0,dtlb_fault
1276
1277	L2_ptep		ptp,pte,t0,va,dtlb_check_alias_20
1278
1279	tlb_lock	spc,ptp,pte,t0,t1,dtlb_check_alias_20
1280	update_accessed	ptp,pte,t0,t1
1281
1282	make_insert_tlb	spc,pte,prot,t1
1283
1284	f_extend	pte,t1
1285
1286	idtlbt          pte,prot
1287
1288	tlb_unlock1	spc,t0,t1
1289	rfir
1290	nop
1291
1292dtlb_check_alias_20:
1293	do_alias	spc,t0,t1,va,pte,prot,dtlb_fault,20
1294
1295	idtlbt          pte,prot
1296
1297	rfir
1298	nop
1299
1300nadtlb_miss_20:
1301	get_pgd		spc,ptp
1302
1303	space_check	spc,t0,nadtlb_fault
1304
1305	L2_ptep		ptp,pte,t0,va,nadtlb_check_alias_20
1306
1307	tlb_lock	spc,ptp,pte,t0,t1,nadtlb_check_alias_20
1308	update_accessed	ptp,pte,t0,t1
1309
1310	make_insert_tlb	spc,pte,prot,t1
1311
1312	f_extend	pte,t1
1313
1314	idtlbt		pte,prot
1315
1316	tlb_unlock1	spc,t0,t1
1317	rfir
1318	nop
1319
1320nadtlb_check_alias_20:
1321	do_alias	spc,t0,t1,va,pte,prot,nadtlb_emulate,20
1322
1323	idtlbt          pte,prot
1324
1325	rfir
1326	nop
1327
1328#endif
1329
1330nadtlb_emulate:
1331
1332	/*
1333	 * Non access misses can be caused by fdc,fic,pdc,lpa,probe and
1334	 * probei instructions. We don't want to fault for these
1335	 * instructions (not only does it not make sense, it can cause
1336	 * deadlocks, since some flushes are done with the mmap
1337	 * semaphore held). If the translation doesn't exist, we can't
1338	 * insert a translation, so have to emulate the side effects
1339	 * of the instruction. Since we don't insert a translation
1340	 * we can get a lot of faults during a flush loop, so it makes
1341	 * sense to try to do it here with minimum overhead. We only
1342	 * emulate fdc,fic,pdc,probew,prober instructions whose base
1343	 * and index registers are not shadowed. We defer everything
1344	 * else to the "slow" path.
1345	 */
1346
1347	mfctl           %cr19,%r9 /* Get iir */
1348
1349	/* PA 2.0 Arch Ref. Book pg 382 has a good description of the insn bits.
1350	   Checks for fdc,fdce,pdc,"fic,4f",prober,probeir,probew, probeiw */
1351
1352	/* Checks for fdc,fdce,pdc,"fic,4f" only */
1353	ldi             0x280,%r16
1354	and             %r9,%r16,%r17
1355	cmpb,<>,n       %r16,%r17,nadtlb_probe_check
1356	bb,>=,n         %r9,26,nadtlb_nullify  /* m bit not set, just nullify */
1357	BL		get_register,%r25
1358	extrw,u         %r9,15,5,%r8           /* Get index register # */
1359	cmpib,COND(=),n        -1,%r1,nadtlb_fault    /* have to use slow path */
1360	copy            %r1,%r24
1361	BL		get_register,%r25
1362	extrw,u         %r9,10,5,%r8           /* Get base register # */
1363	cmpib,COND(=),n        -1,%r1,nadtlb_fault    /* have to use slow path */
1364	BL		set_register,%r25
1365	add,l           %r1,%r24,%r1           /* doesn't affect c/b bits */
1366
1367nadtlb_nullify:
1368	mfctl           %ipsw,%r8
1369	ldil            L%PSW_N,%r9
1370	or              %r8,%r9,%r8            /* Set PSW_N */
1371	mtctl           %r8,%ipsw
1372
1373	rfir
1374	nop
1375
1376	/*
1377		When there is no translation for the probe address then we
1378		must nullify the insn and return zero in the target register.
1379		This will indicate to the calling code that it does not have
1380		write/read privileges to this address.
1381
1382		This should technically work for prober and probew in PA 1.1,
1383		and also probe,r and probe,w in PA 2.0
1384
1385		WARNING: USE ONLY NON-SHADOW REGISTERS WITH PROBE INSN!
1386		THE SLOW-PATH EMULATION HAS NOT BEEN WRITTEN YET.
1387
1388	*/
1389nadtlb_probe_check:
1390	ldi             0x80,%r16
1391	and             %r9,%r16,%r17
1392	cmpb,<>,n       %r16,%r17,nadtlb_fault /* Must be probe,[rw]*/
1393	BL              get_register,%r25      /* Find the target register */
1394	extrw,u         %r9,31,5,%r8           /* Get target register */
1395	cmpib,COND(=),n        -1,%r1,nadtlb_fault    /* have to use slow path */
1396	BL		set_register,%r25
1397	copy            %r0,%r1                /* Write zero to target register */
1398	b nadtlb_nullify                       /* Nullify return insn */
1399	nop
1400
1401
1402#ifdef CONFIG_64BIT
1403itlb_miss_20w:
1404
1405	/*
1406	 * I miss is a little different, since we allow users to fault
1407	 * on the gateway page which is in the kernel address space.
1408	 */
1409
1410	space_adjust	spc,va,t0
1411	get_pgd		spc,ptp
1412	space_check	spc,t0,itlb_fault
1413
1414	L3_ptep		ptp,pte,t0,va,itlb_fault
1415
1416	tlb_lock	spc,ptp,pte,t0,t1,itlb_fault
1417	update_accessed	ptp,pte,t0,t1
1418
1419	make_insert_tlb	spc,pte,prot,t1
1420
1421	iitlbt          pte,prot
1422
1423	tlb_unlock1	spc,t0,t1
1424	rfir
1425	nop
1426
1427naitlb_miss_20w:
1428
1429	/*
1430	 * I miss is a little different, since we allow users to fault
1431	 * on the gateway page which is in the kernel address space.
1432	 */
1433
1434	space_adjust	spc,va,t0
1435	get_pgd		spc,ptp
1436	space_check	spc,t0,naitlb_fault
1437
1438	L3_ptep		ptp,pte,t0,va,naitlb_check_alias_20w
1439
1440	tlb_lock	spc,ptp,pte,t0,t1,naitlb_check_alias_20w
1441	update_accessed	ptp,pte,t0,t1
1442
1443	make_insert_tlb	spc,pte,prot,t1
1444
1445	iitlbt          pte,prot
1446
1447	tlb_unlock1	spc,t0,t1
1448	rfir
1449	nop
1450
1451naitlb_check_alias_20w:
1452	do_alias	spc,t0,t1,va,pte,prot,naitlb_fault,20
1453
1454	iitlbt		pte,prot
1455
1456	rfir
1457	nop
1458
1459#else
1460
1461itlb_miss_11:
1462	get_pgd		spc,ptp
1463
1464	space_check	spc,t0,itlb_fault
1465
1466	L2_ptep		ptp,pte,t0,va,itlb_fault
1467
1468	tlb_lock	spc,ptp,pte,t0,t1,itlb_fault
1469	update_accessed	ptp,pte,t0,t1
1470
1471	make_insert_tlb_11	spc,pte,prot
1472
1473	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1474	mtsp		spc,%sr1
1475
1476	iitlba		pte,(%sr1,va)
1477	iitlbp		prot,(%sr1,va)
1478
1479	mtsp		t1, %sr1	/* Restore sr1 */
1480
1481	tlb_unlock1	spc,t0,t1
1482	rfir
1483	nop
1484
1485naitlb_miss_11:
1486	get_pgd		spc,ptp
1487
1488	space_check	spc,t0,naitlb_fault
1489
1490	L2_ptep		ptp,pte,t0,va,naitlb_check_alias_11
1491
1492	tlb_lock	spc,ptp,pte,t0,t1,naitlb_check_alias_11
1493	update_accessed	ptp,pte,t0,t1
1494
1495	make_insert_tlb_11	spc,pte,prot
1496
1497	mfsp		%sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1498	mtsp		spc,%sr1
1499
1500	iitlba		pte,(%sr1,va)
1501	iitlbp		prot,(%sr1,va)
1502
1503	mtsp		t1, %sr1	/* Restore sr1 */
1504
1505	tlb_unlock1	spc,t0,t1
1506	rfir
1507	nop
1508
1509naitlb_check_alias_11:
1510	do_alias	spc,t0,t1,va,pte,prot,itlb_fault,11
1511
1512	iitlba          pte,(%sr0, va)
1513	iitlbp          prot,(%sr0, va)
1514
1515	rfir
1516	nop
1517
1518
1519itlb_miss_20:
1520	get_pgd		spc,ptp
1521
1522	space_check	spc,t0,itlb_fault
1523
1524	L2_ptep		ptp,pte,t0,va,itlb_fault
1525
1526	tlb_lock	spc,ptp,pte,t0,t1,itlb_fault
1527	update_accessed	ptp,pte,t0,t1
1528
1529	make_insert_tlb	spc,pte,prot,t1
1530
1531	f_extend	pte,t1
1532
1533	iitlbt          pte,prot
1534
1535	tlb_unlock1	spc,t0,t1
1536	rfir
1537	nop
1538
1539naitlb_miss_20:
1540	get_pgd		spc,ptp
1541
1542	space_check	spc,t0,naitlb_fault
1543
1544	L2_ptep		ptp,pte,t0,va,naitlb_check_alias_20
1545
1546	tlb_lock	spc,ptp,pte,t0,t1,naitlb_check_alias_20
1547	update_accessed	ptp,pte,t0,t1
1548
1549	make_insert_tlb	spc,pte,prot,t1
1550
1551	f_extend	pte,t1
1552
1553	iitlbt          pte,prot
1554
1555	tlb_unlock1	spc,t0,t1
1556	rfir
1557	nop
1558
1559naitlb_check_alias_20:
1560	do_alias	spc,t0,t1,va,pte,prot,naitlb_fault,20
1561
1562	iitlbt          pte,prot
1563
1564	rfir
1565	nop
1566
1567#endif
1568
1569#ifdef CONFIG_64BIT
1570
1571dbit_trap_20w:
1572	space_adjust	spc,va,t0
1573	get_pgd		spc,ptp
1574	space_check	spc,t0,dbit_fault
1575
1576	L3_ptep		ptp,pte,t0,va,dbit_fault
1577
1578	tlb_lock	spc,ptp,pte,t0,t1,dbit_fault
1579	update_dirty	ptp,pte,t1
1580
1581	make_insert_tlb	spc,pte,prot,t1
1582
1583	idtlbt          pte,prot
1584
1585	tlb_unlock0	spc,t0,t1
1586	rfir
1587	nop
1588#else
1589
1590dbit_trap_11:
1591
1592	get_pgd		spc,ptp
1593
1594	space_check	spc,t0,dbit_fault
1595
1596	L2_ptep		ptp,pte,t0,va,dbit_fault
1597
1598	tlb_lock	spc,ptp,pte,t0,t1,dbit_fault
1599	update_dirty	ptp,pte,t1
1600
1601	make_insert_tlb_11	spc,pte,prot
1602
1603	mfsp            %sr1,t1  /* Save sr1 so we can use it in tlb inserts */
1604	mtsp		spc,%sr1
1605
1606	idtlba		pte,(%sr1,va)
1607	idtlbp		prot,(%sr1,va)
1608
1609	mtsp            t1, %sr1     /* Restore sr1 */
1610
1611	tlb_unlock0	spc,t0,t1
1612	rfir
1613	nop
1614
1615dbit_trap_20:
1616	get_pgd		spc,ptp
1617
1618	space_check	spc,t0,dbit_fault
1619
1620	L2_ptep		ptp,pte,t0,va,dbit_fault
1621
1622	tlb_lock	spc,ptp,pte,t0,t1,dbit_fault
1623	update_dirty	ptp,pte,t1
1624
1625	make_insert_tlb	spc,pte,prot,t1
1626
1627	f_extend	pte,t1
1628
1629	idtlbt		pte,prot
1630
1631	tlb_unlock0	spc,t0,t1
1632	rfir
1633	nop
1634#endif
1635
1636	.import handle_interruption,code
1637
1638kernel_bad_space:
1639	b               intr_save
1640	ldi             31,%r8  /* Use an unused code */
1641
1642dbit_fault:
1643	b               intr_save
1644	ldi             20,%r8
1645
1646itlb_fault:
1647	b               intr_save
1648	ldi             PARISC_ITLB_TRAP,%r8
1649
1650nadtlb_fault:
1651	b               intr_save
1652	ldi             17,%r8
1653
1654naitlb_fault:
1655	b               intr_save
1656	ldi             16,%r8
1657
1658dtlb_fault:
1659	b               intr_save
1660	ldi             15,%r8
1661
1662	/* Register saving semantics for system calls:
1663
1664	   %r1		   clobbered by system call macro in userspace
1665	   %r2		   saved in PT_REGS by gateway page
1666	   %r3  - %r18	   preserved by C code (saved by signal code)
1667	   %r19 - %r20	   saved in PT_REGS by gateway page
1668	   %r21 - %r22	   non-standard syscall args
1669			   stored in kernel stack by gateway page
1670	   %r23 - %r26	   arg3-arg0, saved in PT_REGS by gateway page
1671	   %r27 - %r30	   saved in PT_REGS by gateway page
1672	   %r31		   syscall return pointer
1673	 */
1674
1675	/* Floating point registers (FIXME: what do we do with these?)
1676
1677	   %fr0  - %fr3	   status/exception, not preserved
1678	   %fr4  - %fr7	   arguments
1679	   %fr8	 - %fr11   not preserved by C code
1680	   %fr12 - %fr21   preserved by C code
1681	   %fr22 - %fr31   not preserved by C code
1682	 */
1683
1684	.macro	reg_save regs
1685	STREG	%r3, PT_GR3(\regs)
1686	STREG	%r4, PT_GR4(\regs)
1687	STREG	%r5, PT_GR5(\regs)
1688	STREG	%r6, PT_GR6(\regs)
1689	STREG	%r7, PT_GR7(\regs)
1690	STREG	%r8, PT_GR8(\regs)
1691	STREG	%r9, PT_GR9(\regs)
1692	STREG   %r10,PT_GR10(\regs)
1693	STREG   %r11,PT_GR11(\regs)
1694	STREG   %r12,PT_GR12(\regs)
1695	STREG   %r13,PT_GR13(\regs)
1696	STREG   %r14,PT_GR14(\regs)
1697	STREG   %r15,PT_GR15(\regs)
1698	STREG   %r16,PT_GR16(\regs)
1699	STREG   %r17,PT_GR17(\regs)
1700	STREG   %r18,PT_GR18(\regs)
1701	.endm
1702
1703	.macro	reg_restore regs
1704	LDREG	PT_GR3(\regs), %r3
1705	LDREG	PT_GR4(\regs), %r4
1706	LDREG	PT_GR5(\regs), %r5
1707	LDREG	PT_GR6(\regs), %r6
1708	LDREG	PT_GR7(\regs), %r7
1709	LDREG	PT_GR8(\regs), %r8
1710	LDREG	PT_GR9(\regs), %r9
1711	LDREG   PT_GR10(\regs),%r10
1712	LDREG   PT_GR11(\regs),%r11
1713	LDREG   PT_GR12(\regs),%r12
1714	LDREG   PT_GR13(\regs),%r13
1715	LDREG   PT_GR14(\regs),%r14
1716	LDREG   PT_GR15(\regs),%r15
1717	LDREG   PT_GR16(\regs),%r16
1718	LDREG   PT_GR17(\regs),%r17
1719	LDREG   PT_GR18(\regs),%r18
1720	.endm
1721
1722	.macro	fork_like name
1723ENTRY_CFI(sys_\name\()_wrapper)
1724	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
1725	ldo	TASK_REGS(%r1),%r1
1726	reg_save %r1
1727	mfctl	%cr27, %r28
1728	ldil	L%sys_\name, %r31
1729	be	R%sys_\name(%sr4,%r31)
1730	STREG	%r28, PT_CR27(%r1)
1731ENDPROC_CFI(sys_\name\()_wrapper)
1732	.endm
1733
1734fork_like clone
1735fork_like clone3
1736fork_like fork
1737fork_like vfork
1738
1739	/* Set the return value for the child */
1740ENTRY(child_return)
1741	BL	schedule_tail, %r2
1742	nop
1743finish_child_return:
1744	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
1745	ldo	TASK_REGS(%r1),%r1	 /* get pt regs */
1746
1747	LDREG	PT_CR27(%r1), %r3
1748	mtctl	%r3, %cr27
1749	reg_restore %r1
1750	b	syscall_exit
1751	copy	%r0,%r28
1752END(child_return)
1753
1754ENTRY_CFI(sys_rt_sigreturn_wrapper)
1755	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26
1756	ldo	TASK_REGS(%r26),%r26	/* get pt regs */
1757	/* Don't save regs, we are going to restore them from sigcontext. */
1758	STREG	%r2, -RP_OFFSET(%r30)
1759#ifdef CONFIG_64BIT
1760	ldo	FRAME_SIZE(%r30), %r30
1761	BL	sys_rt_sigreturn,%r2
1762	ldo	-16(%r30),%r29		/* Reference param save area */
1763#else
1764	BL	sys_rt_sigreturn,%r2
1765	ldo	FRAME_SIZE(%r30), %r30
1766#endif
1767
1768	ldo	-FRAME_SIZE(%r30), %r30
1769	LDREG	-RP_OFFSET(%r30), %r2
1770
1771	/* FIXME: I think we need to restore a few more things here. */
1772	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1773	ldo	TASK_REGS(%r1),%r1	/* get pt regs */
1774	reg_restore %r1
1775
1776	/* If the signal was received while the process was blocked on a
1777	 * syscall, then r2 will take us to syscall_exit; otherwise r2 will
1778	 * take us to syscall_exit_rfi and on to intr_return.
1779	 */
1780	bv	%r0(%r2)
1781	LDREG	PT_GR28(%r1),%r28  /* reload original r28 for syscall_exit */
1782ENDPROC_CFI(sys_rt_sigreturn_wrapper)
1783
1784ENTRY(syscall_exit)
1785	/* NOTE: Not all syscalls exit this way.  rt_sigreturn will exit
1786	 * via syscall_exit_rfi if the signal was received while the process
1787	 * was running.
1788	 */
1789
1790	/* save return value now */
1791
1792	mfctl     %cr30, %r1
1793	LDREG     TI_TASK(%r1),%r1
1794	STREG     %r28,TASK_PT_GR28(%r1)
1795
1796	/* Seems to me that dp could be wrong here, if the syscall involved
1797	 * calling a module, and nothing got round to restoring dp on return.
1798	 */
1799	loadgp
1800
1801syscall_check_resched:
1802
1803	/* check for reschedule */
1804
1805	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19	/* long */
1806	bb,<,n	%r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */
1807
1808	.import do_signal,code
1809syscall_check_sig:
1810	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19
1811	ldi	(_TIF_SIGPENDING|_TIF_NOTIFY_RESUME), %r26
1812	and,COND(<>)	%r19, %r26, %r0
1813	b,n	syscall_restore	/* skip past if we've nothing to do */
1814
1815syscall_do_signal:
1816	/* Save callee-save registers (for sigcontext).
1817	 * FIXME: After this point the process structure should be
1818	 * consistent with all the relevant state of the process
1819	 * before the syscall.  We need to verify this.
1820	 */
1821	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1822	ldo	TASK_REGS(%r1), %r26		/* struct pt_regs *regs */
1823	reg_save %r26
1824
1825#ifdef CONFIG_64BIT
1826	ldo	-16(%r30),%r29			/* Reference param save area */
1827#endif
1828
1829	BL	do_notify_resume,%r2
1830	ldi	1, %r25				/* long in_syscall = 1 */
1831
1832	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1833	ldo	TASK_REGS(%r1), %r20		/* reload pt_regs */
1834	reg_restore %r20
1835
1836	b,n     syscall_check_sig
1837
1838syscall_restore:
1839	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
1840
1841	/* Are we being ptraced? */
1842	ldw	TASK_FLAGS(%r1),%r19
1843	ldi	_TIF_SYSCALL_TRACE_MASK,%r2
1844	and,COND(=)	%r19,%r2,%r0
1845	b,n	syscall_restore_rfi
1846
1847	ldo	TASK_PT_FR31(%r1),%r19		   /* reload fpregs */
1848	rest_fp	%r19
1849
1850	LDREG	TASK_PT_SAR(%r1),%r19		   /* restore SAR */
1851	mtsar	%r19
1852
1853	LDREG	TASK_PT_GR2(%r1),%r2		   /* restore user rp */
1854	LDREG	TASK_PT_GR19(%r1),%r19
1855	LDREG   TASK_PT_GR20(%r1),%r20
1856	LDREG	TASK_PT_GR21(%r1),%r21
1857	LDREG	TASK_PT_GR22(%r1),%r22
1858	LDREG	TASK_PT_GR23(%r1),%r23
1859	LDREG	TASK_PT_GR24(%r1),%r24
1860	LDREG	TASK_PT_GR25(%r1),%r25
1861	LDREG	TASK_PT_GR26(%r1),%r26
1862	LDREG	TASK_PT_GR27(%r1),%r27	   /* restore user dp */
1863	LDREG	TASK_PT_GR28(%r1),%r28	   /* syscall return value */
1864	LDREG	TASK_PT_GR29(%r1),%r29
1865	LDREG	TASK_PT_GR31(%r1),%r31	   /* restore syscall rp */
1866
1867	/* NOTE: We use rsm/ssm pair to make this operation atomic */
1868	LDREG   TASK_PT_GR30(%r1),%r1              /* Get user sp */
1869	rsm     PSW_SM_I, %r0
1870	copy    %r1,%r30                           /* Restore user sp */
1871	mfsp    %sr3,%r1                           /* Get user space id */
1872	mtsp    %r1,%sr7                           /* Restore sr7 */
1873	ssm     PSW_SM_I, %r0
1874
1875	/* Set sr2 to zero for userspace syscalls to work. */
1876	mtsp	%r0,%sr2
1877	mtsp	%r1,%sr4			   /* Restore sr4 */
1878	mtsp	%r1,%sr5			   /* Restore sr5 */
1879	mtsp	%r1,%sr6			   /* Restore sr6 */
1880
1881	depi	3,31,2,%r31			   /* ensure return to user mode. */
1882
1883#ifdef CONFIG_64BIT
1884	/* decide whether to reset the wide mode bit
1885	 *
1886	 * For a syscall, the W bit is stored in the lowest bit
1887	 * of sp.  Extract it and reset W if it is zero */
1888	extrd,u,*<>	%r30,63,1,%r1
1889	rsm	PSW_SM_W, %r0
1890	/* now reset the lowest bit of sp if it was set */
1891	xor	%r30,%r1,%r30
1892#endif
1893	be,n    0(%sr3,%r31)                       /* return to user space */
1894
1895	/* We have to return via an RFI, so that PSW T and R bits can be set
1896	 * appropriately.
1897	 * This sets up pt_regs so we can return via intr_restore, which is not
1898	 * the most efficient way of doing things, but it works.
1899	 */
1900syscall_restore_rfi:
1901	ldo	-1(%r0),%r2			   /* Set recovery cntr to -1 */
1902	mtctl	%r2,%cr0			   /*   for immediate trap */
1903	LDREG	TASK_PT_PSW(%r1),%r2		   /* Get old PSW */
1904	ldi	0x0b,%r20			   /* Create new PSW */
1905	depi	-1,13,1,%r20			   /* C, Q, D, and I bits */
1906
1907	/* The values of SINGLESTEP_BIT and BLOCKSTEP_BIT are
1908	 * set in thread_info.h and converted to PA bitmap
1909	 * numbers in asm-offsets.c */
1910
1911	/* if ((%r19.SINGLESTEP_BIT)) { %r20.27=1} */
1912	extru,=	%r19,TIF_SINGLESTEP_PA_BIT,1,%r0
1913	depi	-1,27,1,%r20			   /* R bit */
1914
1915	/* if ((%r19.BLOCKSTEP_BIT)) { %r20.7=1} */
1916	extru,= %r19,TIF_BLOCKSTEP_PA_BIT,1,%r0
1917	depi	-1,7,1,%r20			   /* T bit */
1918
1919	STREG	%r20,TASK_PT_PSW(%r1)
1920
1921	/* Always store space registers, since sr3 can be changed (e.g. fork) */
1922
1923	mfsp    %sr3,%r25
1924	STREG   %r25,TASK_PT_SR3(%r1)
1925	STREG   %r25,TASK_PT_SR4(%r1)
1926	STREG   %r25,TASK_PT_SR5(%r1)
1927	STREG   %r25,TASK_PT_SR6(%r1)
1928	STREG   %r25,TASK_PT_SR7(%r1)
1929	STREG   %r25,TASK_PT_IASQ0(%r1)
1930	STREG   %r25,TASK_PT_IASQ1(%r1)
1931
1932	/* XXX W bit??? */
1933	/* Now if old D bit is clear, it means we didn't save all registers
1934	 * on syscall entry, so do that now.  This only happens on TRACEME
1935	 * calls, or if someone attached to us while we were on a syscall.
1936	 * We could make this more efficient by not saving r3-r18, but
1937	 * then we wouldn't be able to use the common intr_restore path.
1938	 * It is only for traced processes anyway, so performance is not
1939	 * an issue.
1940	 */
1941	bb,<	%r2,30,pt_regs_ok		   /* Branch if D set */
1942	ldo	TASK_REGS(%r1),%r25
1943	reg_save %r25				   /* Save r3 to r18 */
1944
1945	/* Save the current sr */
1946	mfsp	%sr0,%r2
1947	STREG	%r2,TASK_PT_SR0(%r1)
1948
1949	/* Save the scratch sr */
1950	mfsp	%sr1,%r2
1951	STREG	%r2,TASK_PT_SR1(%r1)
1952
1953	/* sr2 should be set to zero for userspace syscalls */
1954	STREG	%r0,TASK_PT_SR2(%r1)
1955
1956	LDREG	TASK_PT_GR31(%r1),%r2
1957	depi	3,31,2,%r2		   /* ensure return to user mode. */
1958	STREG   %r2,TASK_PT_IAOQ0(%r1)
1959	ldo	4(%r2),%r2
1960	STREG	%r2,TASK_PT_IAOQ1(%r1)
1961	b	intr_restore
1962	copy	%r25,%r16
1963
1964pt_regs_ok:
1965	LDREG	TASK_PT_IAOQ0(%r1),%r2
1966	depi	3,31,2,%r2		   /* ensure return to user mode. */
1967	STREG	%r2,TASK_PT_IAOQ0(%r1)
1968	LDREG	TASK_PT_IAOQ1(%r1),%r2
1969	depi	3,31,2,%r2
1970	STREG	%r2,TASK_PT_IAOQ1(%r1)
1971	b	intr_restore
1972	copy	%r25,%r16
1973
1974syscall_do_resched:
1975	load32	syscall_check_resched,%r2 /* if resched, we start over again */
1976	load32	schedule,%r19
1977	bv	%r0(%r19)		/* jumps to schedule() */
1978#ifdef CONFIG_64BIT
1979	ldo	-16(%r30),%r29		/* Reference param save area */
1980#else
1981	nop
1982#endif
1983END(syscall_exit)
1984
1985
1986#ifdef CONFIG_FUNCTION_TRACER
1987
1988	.import ftrace_function_trampoline,code
1989	.align L1_CACHE_BYTES
1990ENTRY_CFI(mcount, caller)
1991_mcount:
1992	.export _mcount,data
1993	/*
1994	 * The 64bit mcount() function pointer needs 4 dwords, of which the
1995	 * first two are free.  We optimize it here and put 2 instructions for
1996	 * calling mcount(), and 2 instructions for ftrace_stub().  That way we
1997	 * have all on one L1 cacheline.
1998	 */
1999	ldi	0, %arg3
2000	b	ftrace_function_trampoline
2001	copy	%r3, %arg2	/* caller original %sp */
2002ftrace_stub:
2003	.globl ftrace_stub
2004        .type  ftrace_stub, @function
2005#ifdef CONFIG_64BIT
2006	bve	(%rp)
2007#else
2008	bv	%r0(%rp)
2009#endif
2010	nop
2011#ifdef CONFIG_64BIT
2012	.dword mcount
2013	.dword 0 /* code in head.S puts value of global gp here */
2014#endif
2015ENDPROC_CFI(mcount)
2016
2017#ifdef CONFIG_DYNAMIC_FTRACE
2018
2019#ifdef CONFIG_64BIT
2020#define FTRACE_FRAME_SIZE (2*FRAME_SIZE)
2021#else
2022#define FTRACE_FRAME_SIZE FRAME_SIZE
2023#endif
2024ENTRY_CFI(ftrace_caller, caller,frame=FTRACE_FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP)
2025ftrace_caller:
2026	.global ftrace_caller
2027
2028	STREG	%r3, -FTRACE_FRAME_SIZE+1*REG_SZ(%sp)
2029	ldo	-FTRACE_FRAME_SIZE(%sp), %r3
2030	STREG	%rp, -RP_OFFSET(%r3)
2031
2032	/* Offset 0 is already allocated for %r1 */
2033	STREG	%r23, 2*REG_SZ(%r3)
2034	STREG	%r24, 3*REG_SZ(%r3)
2035	STREG	%r25, 4*REG_SZ(%r3)
2036	STREG	%r26, 5*REG_SZ(%r3)
2037	STREG	%r28, 6*REG_SZ(%r3)
2038	STREG	%r29, 7*REG_SZ(%r3)
2039#ifdef CONFIG_64BIT
2040	STREG	%r19, 8*REG_SZ(%r3)
2041	STREG	%r20, 9*REG_SZ(%r3)
2042	STREG	%r21, 10*REG_SZ(%r3)
2043	STREG	%r22, 11*REG_SZ(%r3)
2044	STREG	%r27, 12*REG_SZ(%r3)
2045	STREG	%r31, 13*REG_SZ(%r3)
2046	loadgp
2047	ldo	-16(%sp),%r29
2048#endif
2049	LDREG	0(%r3), %r25
2050	copy	%rp, %r26
2051	ldo	-8(%r25), %r25
2052	ldi	0, %r23		/* no pt_regs */
2053	b,l	ftrace_function_trampoline, %rp
2054	copy	%r3, %r24
2055
2056	LDREG	-RP_OFFSET(%r3), %rp
2057	LDREG	2*REG_SZ(%r3), %r23
2058	LDREG	3*REG_SZ(%r3), %r24
2059	LDREG	4*REG_SZ(%r3), %r25
2060	LDREG	5*REG_SZ(%r3), %r26
2061	LDREG	6*REG_SZ(%r3), %r28
2062	LDREG	7*REG_SZ(%r3), %r29
2063#ifdef CONFIG_64BIT
2064	LDREG	8*REG_SZ(%r3), %r19
2065	LDREG	9*REG_SZ(%r3), %r20
2066	LDREG	10*REG_SZ(%r3), %r21
2067	LDREG	11*REG_SZ(%r3), %r22
2068	LDREG	12*REG_SZ(%r3), %r27
2069	LDREG	13*REG_SZ(%r3), %r31
2070#endif
2071	LDREG	1*REG_SZ(%r3), %r3
2072
2073	LDREGM	-FTRACE_FRAME_SIZE(%sp), %r1
2074	/* Adjust return point to jump back to beginning of traced function */
2075	ldo	-4(%r1), %r1
2076	bv,n	(%r1)
2077
2078ENDPROC_CFI(ftrace_caller)
2079
2080#ifdef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS
2081ENTRY_CFI(ftrace_regs_caller,caller,frame=FTRACE_FRAME_SIZE+PT_SZ_ALGN,
2082	CALLS,SAVE_RP,SAVE_SP)
2083ftrace_regs_caller:
2084	.global ftrace_regs_caller
2085
2086	ldo	-FTRACE_FRAME_SIZE(%sp), %r1
2087	STREG	%rp, -RP_OFFSET(%r1)
2088
2089	copy	%sp, %r1
2090	ldo	PT_SZ_ALGN(%sp), %sp
2091
2092	STREG	%rp, PT_GR2(%r1)
2093	STREG	%r3, PT_GR3(%r1)
2094	STREG	%r4, PT_GR4(%r1)
2095	STREG	%r5, PT_GR5(%r1)
2096	STREG	%r6, PT_GR6(%r1)
2097	STREG	%r7, PT_GR7(%r1)
2098	STREG	%r8, PT_GR8(%r1)
2099	STREG	%r9, PT_GR9(%r1)
2100	STREG   %r10, PT_GR10(%r1)
2101	STREG   %r11, PT_GR11(%r1)
2102	STREG   %r12, PT_GR12(%r1)
2103	STREG   %r13, PT_GR13(%r1)
2104	STREG   %r14, PT_GR14(%r1)
2105	STREG   %r15, PT_GR15(%r1)
2106	STREG   %r16, PT_GR16(%r1)
2107	STREG   %r17, PT_GR17(%r1)
2108	STREG   %r18, PT_GR18(%r1)
2109	STREG	%r19, PT_GR19(%r1)
2110	STREG	%r20, PT_GR20(%r1)
2111	STREG	%r21, PT_GR21(%r1)
2112	STREG	%r22, PT_GR22(%r1)
2113	STREG	%r23, PT_GR23(%r1)
2114	STREG	%r24, PT_GR24(%r1)
2115	STREG	%r25, PT_GR25(%r1)
2116	STREG	%r26, PT_GR26(%r1)
2117	STREG	%r27, PT_GR27(%r1)
2118	STREG	%r28, PT_GR28(%r1)
2119	STREG	%r29, PT_GR29(%r1)
2120	STREG	%r30, PT_GR30(%r1)
2121	STREG	%r31, PT_GR31(%r1)
2122	mfctl	%cr11, %r26
2123	STREG	%r26, PT_SAR(%r1)
2124
2125	copy	%rp, %r26
2126	LDREG	-FTRACE_FRAME_SIZE-PT_SZ_ALGN(%sp), %r25
2127	ldo	-8(%r25), %r25
2128	ldo	-FTRACE_FRAME_SIZE(%r1), %arg2
2129	b,l	ftrace_function_trampoline, %rp
2130	copy	%r1, %arg3 /* struct pt_regs */
2131
2132	ldo	-PT_SZ_ALGN(%sp), %r1
2133
2134	LDREG	PT_SAR(%r1), %rp
2135	mtctl	%rp, %cr11
2136
2137	LDREG	PT_GR2(%r1), %rp
2138	LDREG	PT_GR3(%r1), %r3
2139	LDREG	PT_GR4(%r1), %r4
2140	LDREG	PT_GR5(%r1), %r5
2141	LDREG	PT_GR6(%r1), %r6
2142	LDREG	PT_GR7(%r1), %r7
2143	LDREG	PT_GR8(%r1), %r8
2144	LDREG	PT_GR9(%r1), %r9
2145	LDREG   PT_GR10(%r1),%r10
2146	LDREG   PT_GR11(%r1),%r11
2147	LDREG   PT_GR12(%r1),%r12
2148	LDREG   PT_GR13(%r1),%r13
2149	LDREG   PT_GR14(%r1),%r14
2150	LDREG   PT_GR15(%r1),%r15
2151	LDREG   PT_GR16(%r1),%r16
2152	LDREG   PT_GR17(%r1),%r17
2153	LDREG   PT_GR18(%r1),%r18
2154	LDREG   PT_GR19(%r1),%r19
2155	LDREG   PT_GR20(%r1),%r20
2156	LDREG   PT_GR21(%r1),%r21
2157	LDREG   PT_GR22(%r1),%r22
2158	LDREG   PT_GR23(%r1),%r23
2159	LDREG   PT_GR24(%r1),%r24
2160	LDREG   PT_GR25(%r1),%r25
2161	LDREG   PT_GR26(%r1),%r26
2162	LDREG   PT_GR27(%r1),%r27
2163	LDREG   PT_GR28(%r1),%r28
2164	LDREG   PT_GR29(%r1),%r29
2165	LDREG   PT_GR30(%r1),%r30
2166	LDREG   PT_GR31(%r1),%r31
2167
2168	ldo	-PT_SZ_ALGN(%sp), %sp
2169	LDREGM	-FTRACE_FRAME_SIZE(%sp), %r1
2170	/* Adjust return point to jump back to beginning of traced function */
2171	ldo	-4(%r1), %r1
2172	bv,n	(%r1)
2173
2174ENDPROC_CFI(ftrace_regs_caller)
2175
2176#endif
2177#endif
2178
2179#ifdef CONFIG_FUNCTION_GRAPH_TRACER
2180	.align 8
2181ENTRY_CFI(return_to_handler, caller,frame=FRAME_SIZE)
2182	.export parisc_return_to_handler,data
2183parisc_return_to_handler:
2184	copy %r3,%r1
2185	STREG %r0,-RP_OFFSET(%sp)	/* store 0 as %rp */
2186	copy %sp,%r3
2187	STREGM %r1,FRAME_SIZE(%sp)
2188	STREG %ret0,8(%r3)
2189	STREG %ret1,16(%r3)
2190
2191#ifdef CONFIG_64BIT
2192	loadgp
2193#endif
2194
2195	/* call ftrace_return_to_handler(0) */
2196	.import ftrace_return_to_handler,code
2197	load32 ftrace_return_to_handler,%ret0
2198	load32 .Lftrace_ret,%r2
2199#ifdef CONFIG_64BIT
2200	ldo -16(%sp),%ret1		/* Reference param save area */
2201	bve	(%ret0)
2202#else
2203	bv	%r0(%ret0)
2204#endif
2205	ldi 0,%r26
2206.Lftrace_ret:
2207	copy %ret0,%rp
2208
2209	/* restore original return values */
2210	LDREG 8(%r3),%ret0
2211	LDREG 16(%r3),%ret1
2212
2213	/* return from function */
2214#ifdef CONFIG_64BIT
2215	bve	(%rp)
2216#else
2217	bv	%r0(%rp)
2218#endif
2219	LDREGM -FRAME_SIZE(%sp),%r3
2220ENDPROC_CFI(return_to_handler)
2221
2222#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
2223
2224#endif	/* CONFIG_FUNCTION_TRACER */
2225
2226#ifdef CONFIG_IRQSTACKS
2227/* void call_on_stack(unsigned long param1, void *func,
2228		      unsigned long new_stack) */
2229ENTRY_CFI(call_on_stack, FRAME=2*FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP)
2230ENTRY(_call_on_stack)
2231	copy	%sp, %r1
2232
2233	/* Regarding the HPPA calling conventions for function pointers,
2234	   we assume the PIC register is not changed across call.  For
2235	   CONFIG_64BIT, the argument pointer is left to point at the
2236	   argument region allocated for the call to call_on_stack. */
2237
2238	/* Switch to new stack.  We allocate two frames.  */
2239	ldo	2*FRAME_SIZE(%arg2), %sp
2240# ifdef CONFIG_64BIT
2241	/* Save previous stack pointer and return pointer in frame marker */
2242	STREG	%rp, -FRAME_SIZE-RP_OFFSET(%sp)
2243	/* Calls always use function descriptor */
2244	LDREG	16(%arg1), %arg1
2245	bve,l	(%arg1), %rp
2246	STREG	%r1, -FRAME_SIZE-REG_SZ(%sp)
2247	LDREG	-FRAME_SIZE-RP_OFFSET(%sp), %rp
2248	bve	(%rp)
2249	LDREG	-FRAME_SIZE-REG_SZ(%sp), %sp
2250# else
2251	/* Save previous stack pointer and return pointer in frame marker */
2252	STREG	%r1, -FRAME_SIZE-REG_SZ(%sp)
2253	STREG	%rp, -FRAME_SIZE-RP_OFFSET(%sp)
2254	/* Calls use function descriptor if PLABEL bit is set */
2255	bb,>=,n	%arg1, 30, 1f
2256	depwi	0,31,2, %arg1
2257	LDREG	0(%arg1), %arg1
22581:
2259	be,l	0(%sr4,%arg1), %sr0, %r31
2260	copy	%r31, %rp
2261	LDREG	-FRAME_SIZE-RP_OFFSET(%sp), %rp
2262	bv	(%rp)
2263	LDREG	-FRAME_SIZE-REG_SZ(%sp), %sp
2264# endif /* CONFIG_64BIT */
2265ENDPROC_CFI(call_on_stack)
2266#endif /* CONFIG_IRQSTACKS */
2267
2268ENTRY_CFI(get_register)
2269	/*
2270	 * get_register is used by the non access tlb miss handlers to
2271	 * copy the value of the general register specified in r8 into
2272	 * r1. This routine can't be used for shadowed registers, since
2273	 * the rfir will restore the original value. So, for the shadowed
2274	 * registers we put a -1 into r1 to indicate that the register
2275	 * should not be used (the register being copied could also have
2276	 * a -1 in it, but that is OK, it just means that we will have
2277	 * to use the slow path instead).
2278	 */
2279	blr     %r8,%r0
2280	nop
2281	bv      %r0(%r25)    /* r0 */
2282	copy    %r0,%r1
2283	bv      %r0(%r25)    /* r1 - shadowed */
2284	ldi     -1,%r1
2285	bv      %r0(%r25)    /* r2 */
2286	copy    %r2,%r1
2287	bv      %r0(%r25)    /* r3 */
2288	copy    %r3,%r1
2289	bv      %r0(%r25)    /* r4 */
2290	copy    %r4,%r1
2291	bv      %r0(%r25)    /* r5 */
2292	copy    %r5,%r1
2293	bv      %r0(%r25)    /* r6 */
2294	copy    %r6,%r1
2295	bv      %r0(%r25)    /* r7 */
2296	copy    %r7,%r1
2297	bv      %r0(%r25)    /* r8 - shadowed */
2298	ldi     -1,%r1
2299	bv      %r0(%r25)    /* r9 - shadowed */
2300	ldi     -1,%r1
2301	bv      %r0(%r25)    /* r10 */
2302	copy    %r10,%r1
2303	bv      %r0(%r25)    /* r11 */
2304	copy    %r11,%r1
2305	bv      %r0(%r25)    /* r12 */
2306	copy    %r12,%r1
2307	bv      %r0(%r25)    /* r13 */
2308	copy    %r13,%r1
2309	bv      %r0(%r25)    /* r14 */
2310	copy    %r14,%r1
2311	bv      %r0(%r25)    /* r15 */
2312	copy    %r15,%r1
2313	bv      %r0(%r25)    /* r16 - shadowed */
2314	ldi     -1,%r1
2315	bv      %r0(%r25)    /* r17 - shadowed */
2316	ldi     -1,%r1
2317	bv      %r0(%r25)    /* r18 */
2318	copy    %r18,%r1
2319	bv      %r0(%r25)    /* r19 */
2320	copy    %r19,%r1
2321	bv      %r0(%r25)    /* r20 */
2322	copy    %r20,%r1
2323	bv      %r0(%r25)    /* r21 */
2324	copy    %r21,%r1
2325	bv      %r0(%r25)    /* r22 */
2326	copy    %r22,%r1
2327	bv      %r0(%r25)    /* r23 */
2328	copy    %r23,%r1
2329	bv      %r0(%r25)    /* r24 - shadowed */
2330	ldi     -1,%r1
2331	bv      %r0(%r25)    /* r25 - shadowed */
2332	ldi     -1,%r1
2333	bv      %r0(%r25)    /* r26 */
2334	copy    %r26,%r1
2335	bv      %r0(%r25)    /* r27 */
2336	copy    %r27,%r1
2337	bv      %r0(%r25)    /* r28 */
2338	copy    %r28,%r1
2339	bv      %r0(%r25)    /* r29 */
2340	copy    %r29,%r1
2341	bv      %r0(%r25)    /* r30 */
2342	copy    %r30,%r1
2343	bv      %r0(%r25)    /* r31 */
2344	copy    %r31,%r1
2345ENDPROC_CFI(get_register)
2346
2347
2348ENTRY_CFI(set_register)
2349	/*
2350	 * set_register is used by the non access tlb miss handlers to
2351	 * copy the value of r1 into the general register specified in
2352	 * r8.
2353	 */
2354	blr     %r8,%r0
2355	nop
2356	bv      %r0(%r25)    /* r0 (silly, but it is a place holder) */
2357	copy    %r1,%r0
2358	bv      %r0(%r25)    /* r1 */
2359	copy    %r1,%r1
2360	bv      %r0(%r25)    /* r2 */
2361	copy    %r1,%r2
2362	bv      %r0(%r25)    /* r3 */
2363	copy    %r1,%r3
2364	bv      %r0(%r25)    /* r4 */
2365	copy    %r1,%r4
2366	bv      %r0(%r25)    /* r5 */
2367	copy    %r1,%r5
2368	bv      %r0(%r25)    /* r6 */
2369	copy    %r1,%r6
2370	bv      %r0(%r25)    /* r7 */
2371	copy    %r1,%r7
2372	bv      %r0(%r25)    /* r8 */
2373	copy    %r1,%r8
2374	bv      %r0(%r25)    /* r9 */
2375	copy    %r1,%r9
2376	bv      %r0(%r25)    /* r10 */
2377	copy    %r1,%r10
2378	bv      %r0(%r25)    /* r11 */
2379	copy    %r1,%r11
2380	bv      %r0(%r25)    /* r12 */
2381	copy    %r1,%r12
2382	bv      %r0(%r25)    /* r13 */
2383	copy    %r1,%r13
2384	bv      %r0(%r25)    /* r14 */
2385	copy    %r1,%r14
2386	bv      %r0(%r25)    /* r15 */
2387	copy    %r1,%r15
2388	bv      %r0(%r25)    /* r16 */
2389	copy    %r1,%r16
2390	bv      %r0(%r25)    /* r17 */
2391	copy    %r1,%r17
2392	bv      %r0(%r25)    /* r18 */
2393	copy    %r1,%r18
2394	bv      %r0(%r25)    /* r19 */
2395	copy    %r1,%r19
2396	bv      %r0(%r25)    /* r20 */
2397	copy    %r1,%r20
2398	bv      %r0(%r25)    /* r21 */
2399	copy    %r1,%r21
2400	bv      %r0(%r25)    /* r22 */
2401	copy    %r1,%r22
2402	bv      %r0(%r25)    /* r23 */
2403	copy    %r1,%r23
2404	bv      %r0(%r25)    /* r24 */
2405	copy    %r1,%r24
2406	bv      %r0(%r25)    /* r25 */
2407	copy    %r1,%r25
2408	bv      %r0(%r25)    /* r26 */
2409	copy    %r1,%r26
2410	bv      %r0(%r25)    /* r27 */
2411	copy    %r1,%r27
2412	bv      %r0(%r25)    /* r28 */
2413	copy    %r1,%r28
2414	bv      %r0(%r25)    /* r29 */
2415	copy    %r1,%r29
2416	bv      %r0(%r25)    /* r30 */
2417	copy    %r1,%r30
2418	bv      %r0(%r25)    /* r31 */
2419	copy    %r1,%r31
2420ENDPROC_CFI(set_register)
2421
2422