xref: /openbmc/linux/arch/ia64/kernel/mca_asm.S (revision 65844828)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * File:	mca_asm.S
4 * Purpose:	assembly portion of the IA64 MCA handling
5 *
6 * Mods by cfleck to integrate into kernel build
7 *
8 * 2000-03-15 David Mosberger-Tang <davidm@hpl.hp.com>
9 *		Added various stop bits to get a clean compile
10 *
11 * 2000-03-29 Chuck Fleckenstein <cfleck@co.intel.com>
12 *		Added code to save INIT handoff state in pt_regs format,
13 *		switch to temp kstack, switch modes, jump to C INIT handler
14 *
15 * 2002-01-04 J.Hall <jenna.s.hall@intel.com>
16 *		Before entering virtual mode code:
17 *		 1. Check for TLB CPU error
18 *		 2. Restore current thread pointer to kr6
19 *		 3. Move stack ptr 16 bytes to conform to C calling convention
20 *
21 * 2004-11-12 Russ Anderson <rja@sgi.com>
22 *		Added per cpu MCA/INIT stack save areas.
23 *
24 * 2005-12-08 Keith Owens <kaos@sgi.com>
25 *		Use per cpu MCA/INIT stacks for all data.
26 */
27#include <linux/threads.h>
28#include <linux/pgtable.h>
29
30#include <asm/asmmacro.h>
31#include <asm/processor.h>
32#include <asm/mca_asm.h>
33#include <asm/mca.h>
34
35#include "entry.h"
36
37#define GET_IA64_MCA_DATA(reg)						\
38	GET_THIS_PADDR(reg, ia64_mca_data)				\
39	;;								\
40	ld8 reg=[reg]
41
42	.global ia64_do_tlb_purge
43	.global ia64_os_mca_dispatch
44	.global ia64_os_init_on_kdump
45	.global ia64_os_init_dispatch_monarch
46	.global ia64_os_init_dispatch_slave
47
48	.text
49	.align 16
50
51//StartMain////////////////////////////////////////////////////////////////////
52
53/*
54 * Just the TLB purge part is moved to a separate function
55 * so we can re-use the code for cpu hotplug code as well
56 * Caller should now setup b1, so we can branch once the
57 * tlb flush is complete.
58 */
59
60ia64_do_tlb_purge:
61#define O(member)	IA64_CPUINFO_##member##_OFFSET
62
63	GET_THIS_PADDR(r2, ia64_cpu_info) // load phys addr of cpu_info into r2
64	;;
65	addl r17=O(PTCE_STRIDE),r2
66	addl r2=O(PTCE_BASE),r2
67	;;
68	ld8 r18=[r2],(O(PTCE_COUNT)-O(PTCE_BASE));;	// r18=ptce_base
69	ld4 r19=[r2],4					// r19=ptce_count[0]
70	ld4 r21=[r17],4					// r21=ptce_stride[0]
71	;;
72	ld4 r20=[r2]					// r20=ptce_count[1]
73	ld4 r22=[r17]					// r22=ptce_stride[1]
74	mov r24=0
75	;;
76	adds r20=-1,r20
77	;;
78#undef O
79
802:
81	cmp.ltu p6,p7=r24,r19
82(p7)	br.cond.dpnt.few 4f
83	mov ar.lc=r20
843:
85	ptc.e r18
86	;;
87	add r18=r22,r18
88	br.cloop.sptk.few 3b
89	;;
90	add r18=r21,r18
91	add r24=1,r24
92	;;
93	br.sptk.few 2b
944:
95	srlz.i 			// srlz.i implies srlz.d
96	;;
97
98        // Now purge addresses formerly mapped by TR registers
99	// 1. Purge ITR&DTR for kernel.
100	movl r16=KERNEL_START
101	mov r18=KERNEL_TR_PAGE_SHIFT<<2
102	;;
103	ptr.i r16, r18
104	ptr.d r16, r18
105	;;
106	srlz.i
107	;;
108	srlz.d
109	;;
110	// 3. Purge ITR for PAL code.
111	GET_THIS_PADDR(r2, ia64_mca_pal_base)
112	;;
113	ld8 r16=[r2]
114	mov r18=IA64_GRANULE_SHIFT<<2
115	;;
116	ptr.i r16,r18
117	;;
118	srlz.i
119	;;
120	// 4. Purge DTR for stack.
121	mov r16=IA64_KR(CURRENT_STACK)
122	;;
123	shl r16=r16,IA64_GRANULE_SHIFT
124	movl r19=PAGE_OFFSET
125	;;
126	add r16=r19,r16
127	mov r18=IA64_GRANULE_SHIFT<<2
128	;;
129	ptr.d r16,r18
130	;;
131	srlz.i
132	;;
133	// Now branch away to caller.
134	br.sptk.many b1
135	;;
136
137//EndMain//////////////////////////////////////////////////////////////////////
138
139//StartMain////////////////////////////////////////////////////////////////////
140
141ia64_os_mca_dispatch:
142	mov r3=IA64_MCA_CPU_MCA_STACK_OFFSET	// use the MCA stack
143	LOAD_PHYSICAL(p0,r2,1f)			// return address
144	mov r19=1				// All MCA events are treated as monarch (for now)
145	br.sptk ia64_state_save			// save the state that is not in minstate
1461:
147
148	GET_IA64_MCA_DATA(r2)
149	// Using MCA stack, struct ia64_sal_os_state, variable proc_state_param
150	;;
151	add r3=IA64_MCA_CPU_MCA_STACK_OFFSET+MCA_SOS_OFFSET+SOS(PROC_STATE_PARAM), r2
152	;;
153	ld8 r18=[r3]				// Get processor state parameter on existing PALE_CHECK.
154	;;
155	tbit.nz p6,p7=r18,60
156(p7)	br.spnt done_tlb_purge_and_reload
157
158	// The following code purges TC and TR entries. Then reload all TC entries.
159	// Purge percpu data TC entries.
160begin_tlb_purge_and_reload:
161	movl r18=ia64_reload_tr;;
162	LOAD_PHYSICAL(p0,r18,ia64_reload_tr);;
163	mov b1=r18;;
164	br.sptk.many ia64_do_tlb_purge;;
165
166ia64_reload_tr:
167	// Finally reload the TR registers.
168	// 1. Reload DTR/ITR registers for kernel.
169	mov r18=KERNEL_TR_PAGE_SHIFT<<2
170	movl r17=KERNEL_START
171	;;
172	mov cr.itir=r18
173	mov cr.ifa=r17
174        mov r16=IA64_TR_KERNEL
175	mov r19=ip
176	movl r18=PAGE_KERNEL
177	;;
178        dep r17=0,r19,0, KERNEL_TR_PAGE_SHIFT
179	;;
180	or r18=r17,r18
181	;;
182        itr.i itr[r16]=r18
183	;;
184        itr.d dtr[r16]=r18
185        ;;
186	srlz.i
187	srlz.d
188	;;
189	// 3. Reload ITR for PAL code.
190	GET_THIS_PADDR(r2, ia64_mca_pal_pte)
191	;;
192	ld8 r18=[r2]			// load PAL PTE
193	;;
194	GET_THIS_PADDR(r2, ia64_mca_pal_base)
195	;;
196	ld8 r16=[r2]			// load PAL vaddr
197	mov r19=IA64_GRANULE_SHIFT<<2
198	;;
199	mov cr.itir=r19
200	mov cr.ifa=r16
201	mov r20=IA64_TR_PALCODE
202	;;
203	itr.i itr[r20]=r18
204	;;
205	srlz.i
206	;;
207	// 4. Reload DTR for stack.
208	mov r16=IA64_KR(CURRENT_STACK)
209	;;
210	shl r16=r16,IA64_GRANULE_SHIFT
211	movl r19=PAGE_OFFSET
212	;;
213	add r18=r19,r16
214	movl r20=PAGE_KERNEL
215	;;
216	add r16=r20,r16
217	mov r19=IA64_GRANULE_SHIFT<<2
218	;;
219	mov cr.itir=r19
220	mov cr.ifa=r18
221	mov r20=IA64_TR_CURRENT_STACK
222	;;
223	itr.d dtr[r20]=r16
224	GET_THIS_PADDR(r2, ia64_mca_tr_reload)
225	mov r18 = 1
226	;;
227	srlz.d
228	;;
229	st8 [r2] =r18
230	;;
231
232done_tlb_purge_and_reload:
233
234	// switch to per cpu MCA stack
235	mov r3=IA64_MCA_CPU_MCA_STACK_OFFSET	// use the MCA stack
236	LOAD_PHYSICAL(p0,r2,1f)			// return address
237	br.sptk ia64_new_stack
2381:
239
240	// everything saved, now we can set the kernel registers
241	mov r3=IA64_MCA_CPU_MCA_STACK_OFFSET	// use the MCA stack
242	LOAD_PHYSICAL(p0,r2,1f)			// return address
243	br.sptk ia64_set_kernel_registers
2441:
245
246	// This must be done in physical mode
247	GET_IA64_MCA_DATA(r2)
248	;;
249	mov r7=r2
250
251        // Enter virtual mode from physical mode
252	VIRTUAL_MODE_ENTER(r2, r3, ia64_os_mca_virtual_begin, r4)
253
254	// This code returns to SAL via SOS r2, in general SAL has no unwind
255	// data.  To get a clean termination when backtracing the C MCA/INIT
256	// handler, set a dummy return address of 0 in this routine.  That
257	// requires that ia64_os_mca_virtual_begin be a global function.
258ENTRY(ia64_os_mca_virtual_begin)
259	.prologue
260	.save rp,r0
261	.body
262
263	mov ar.rsc=3				// set eager mode for C handler
264	mov r2=r7				// see GET_IA64_MCA_DATA above
265	;;
266
267	// Call virtual mode handler
268	alloc r14=ar.pfs,0,0,3,0
269	;;
270	DATA_PA_TO_VA(r2,r7)
271	;;
272	add out0=IA64_MCA_CPU_MCA_STACK_OFFSET+MCA_PT_REGS_OFFSET, r2
273	add out1=IA64_MCA_CPU_MCA_STACK_OFFSET+MCA_SWITCH_STACK_OFFSET, r2
274	add out2=IA64_MCA_CPU_MCA_STACK_OFFSET+MCA_SOS_OFFSET, r2
275	br.call.sptk.many    b0=ia64_mca_handler
276
277	// Revert back to physical mode before going back to SAL
278	PHYSICAL_MODE_ENTER(r2, r3, ia64_os_mca_virtual_end, r4)
279ia64_os_mca_virtual_end:
280
281END(ia64_os_mca_virtual_begin)
282
283	// switch back to previous stack
284	alloc r14=ar.pfs,0,0,0,0		// remove the MCA handler frame
285	mov r3=IA64_MCA_CPU_MCA_STACK_OFFSET	// use the MCA stack
286	LOAD_PHYSICAL(p0,r2,1f)			// return address
287	br.sptk ia64_old_stack
2881:
289
290	mov r3=IA64_MCA_CPU_MCA_STACK_OFFSET	// use the MCA stack
291	LOAD_PHYSICAL(p0,r2,1f)			// return address
292	br.sptk ia64_state_restore		// restore the SAL state
2931:
294
295	mov		b0=r12			// SAL_CHECK return address
296
297	br		b0
298
299//EndMain//////////////////////////////////////////////////////////////////////
300
301//StartMain////////////////////////////////////////////////////////////////////
302
303//
304// NOP init handler for kdump.  In panic situation, we may receive INIT
305// while kernel transition.  Since we initialize registers on leave from
306// current kernel, no longer monarch/slave handlers of current kernel in
307// virtual mode are called safely.
308// We can unregister these init handlers from SAL, however then the INIT
309// will result in warmboot by SAL and we cannot retrieve the crashdump.
310// Therefore register this NOP function to SAL, to prevent entering virtual
311// mode and resulting warmboot by SAL.
312//
313ia64_os_init_on_kdump:
314	mov		r8=r0		// IA64_INIT_RESUME
315	mov             r9=r10		// SAL_GP
316	mov		r22=r17		// *minstate
317	;;
318	mov		r10=r0		// return to same context
319	mov		b0=r12		// SAL_CHECK return address
320	br		b0
321
322//
323// SAL to OS entry point for INIT on all processors.  This has been defined for
324// registration purposes with SAL as a part of ia64_mca_init.  Monarch and
325// slave INIT have identical processing, except for the value of the
326// sos->monarch flag in r19.
327//
328
329ia64_os_init_dispatch_monarch:
330	mov r19=1				// Bow, bow, ye lower middle classes!
331	br.sptk ia64_os_init_dispatch
332
333ia64_os_init_dispatch_slave:
334	mov r19=0				// <igor>yeth, mathter</igor>
335
336ia64_os_init_dispatch:
337
338	mov r3=IA64_MCA_CPU_INIT_STACK_OFFSET	// use the INIT stack
339	LOAD_PHYSICAL(p0,r2,1f)			// return address
340	br.sptk ia64_state_save			// save the state that is not in minstate
3411:
342
343	// switch to per cpu INIT stack
344	mov r3=IA64_MCA_CPU_INIT_STACK_OFFSET	// use the INIT stack
345	LOAD_PHYSICAL(p0,r2,1f)			// return address
346	br.sptk ia64_new_stack
3471:
348
349	// everything saved, now we can set the kernel registers
350	mov r3=IA64_MCA_CPU_INIT_STACK_OFFSET	// use the INIT stack
351	LOAD_PHYSICAL(p0,r2,1f)			// return address
352	br.sptk ia64_set_kernel_registers
3531:
354
355	// This must be done in physical mode
356	GET_IA64_MCA_DATA(r2)
357	;;
358	mov r7=r2
359
360        // Enter virtual mode from physical mode
361	VIRTUAL_MODE_ENTER(r2, r3, ia64_os_init_virtual_begin, r4)
362
363	// This code returns to SAL via SOS r2, in general SAL has no unwind
364	// data.  To get a clean termination when backtracing the C MCA/INIT
365	// handler, set a dummy return address of 0 in this routine.  That
366	// requires that ia64_os_init_virtual_begin be a global function.
367ENTRY(ia64_os_init_virtual_begin)
368	.prologue
369	.save rp,r0
370	.body
371
372	mov ar.rsc=3				// set eager mode for C handler
373	mov r2=r7				// see GET_IA64_MCA_DATA above
374	;;
375
376	// Call virtual mode handler
377	alloc r14=ar.pfs,0,0,3,0
378	;;
379	DATA_PA_TO_VA(r2,r7)
380	;;
381	add out0=IA64_MCA_CPU_INIT_STACK_OFFSET+MCA_PT_REGS_OFFSET, r2
382	add out1=IA64_MCA_CPU_INIT_STACK_OFFSET+MCA_SWITCH_STACK_OFFSET, r2
383	add out2=IA64_MCA_CPU_INIT_STACK_OFFSET+MCA_SOS_OFFSET, r2
384	br.call.sptk.many    b0=ia64_init_handler
385
386	// Revert back to physical mode before going back to SAL
387	PHYSICAL_MODE_ENTER(r2, r3, ia64_os_init_virtual_end, r4)
388ia64_os_init_virtual_end:
389
390END(ia64_os_init_virtual_begin)
391
392	mov r3=IA64_MCA_CPU_INIT_STACK_OFFSET	// use the INIT stack
393	LOAD_PHYSICAL(p0,r2,1f)			// return address
394	br.sptk ia64_state_restore		// restore the SAL state
3951:
396
397	// switch back to previous stack
398	alloc r14=ar.pfs,0,0,0,0		// remove the INIT handler frame
399	mov r3=IA64_MCA_CPU_INIT_STACK_OFFSET	// use the INIT stack
400	LOAD_PHYSICAL(p0,r2,1f)			// return address
401	br.sptk ia64_old_stack
4021:
403
404	mov		b0=r12			// SAL_CHECK return address
405	br		b0
406
407//EndMain//////////////////////////////////////////////////////////////////////
408
409// common defines for the stubs
410#define	ms		r4
411#define	regs		r5
412#define	temp1		r2	/* careful, it overlaps with input registers */
413#define	temp2		r3	/* careful, it overlaps with input registers */
414#define	temp3		r7
415#define	temp4		r14
416
417
418//++
419// Name:
420//	ia64_state_save()
421//
422// Stub Description:
423//
424//	Save the state that is not in minstate.  This is sensitive to the layout of
425//	struct ia64_sal_os_state in mca.h.
426//
427//	r2 contains the return address, r3 contains either
428//	IA64_MCA_CPU_MCA_STACK_OFFSET or IA64_MCA_CPU_INIT_STACK_OFFSET.
429//
430//	The OS to SAL section of struct ia64_sal_os_state is set to a default
431//	value of cold boot (MCA) or warm boot (INIT) and return to the same
432//	context.  ia64_sal_os_state is also used to hold some registers that
433//	need to be saved and restored across the stack switches.
434//
435//	Most input registers to this stub come from PAL/SAL
436//	r1  os gp, physical
437//	r8  pal_proc entry point
438//	r9  sal_proc entry point
439//	r10 sal gp
440//	r11 MCA - rendevzous state, INIT - reason code
441//	r12 sal return address
442//	r17 pal min_state
443//	r18 processor state parameter
444//	r19 monarch flag, set by the caller of this routine
445//
446//	In addition to the SAL to OS state, this routine saves all the
447//	registers that appear in struct pt_regs and struct switch_stack,
448//	excluding those that are already in the PAL minstate area.  This
449//	results in a partial pt_regs and switch_stack, the C code copies the
450//	remaining registers from PAL minstate to pt_regs and switch_stack.  The
451//	resulting structures contain all the state of the original process when
452//	MCA/INIT occurred.
453//
454//--
455
456ia64_state_save:
457	add regs=MCA_SOS_OFFSET, r3
458	add ms=MCA_SOS_OFFSET+8, r3
459	mov b0=r2		// save return address
460	cmp.eq p1,p2=IA64_MCA_CPU_MCA_STACK_OFFSET, r3
461	;;
462	GET_IA64_MCA_DATA(temp2)
463	;;
464	add temp1=temp2, regs	// struct ia64_sal_os_state on MCA or INIT stack
465	add temp2=temp2, ms	// struct ia64_sal_os_state+8 on MCA or INIT stack
466	;;
467	mov regs=temp1		// save the start of sos
468	st8 [temp1]=r1,16	// os_gp
469	st8 [temp2]=r8,16	// pal_proc
470	;;
471	st8 [temp1]=r9,16	// sal_proc
472	st8 [temp2]=r11,16	// rv_rc
473	mov r11=cr.iipa
474	;;
475	st8 [temp1]=r18		// proc_state_param
476	st8 [temp2]=r19		// monarch
477	mov r6=IA64_KR(CURRENT)
478	add temp1=SOS(SAL_RA), regs
479	add temp2=SOS(SAL_GP), regs
480	;;
481	st8 [temp1]=r12,16	// sal_ra
482	st8 [temp2]=r10,16	// sal_gp
483	mov r12=cr.isr
484	;;
485	st8 [temp1]=r17,16	// pal_min_state
486	st8 [temp2]=r6,16	// prev_IA64_KR_CURRENT
487	mov r6=IA64_KR(CURRENT_STACK)
488	;;
489	st8 [temp1]=r6,16	// prev_IA64_KR_CURRENT_STACK
490	st8 [temp2]=r0,16	// prev_task, starts off as NULL
491	mov r6=cr.ifa
492	;;
493	st8 [temp1]=r12,16	// cr.isr
494	st8 [temp2]=r6,16	// cr.ifa
495	mov r12=cr.itir
496	;;
497	st8 [temp1]=r12,16	// cr.itir
498	st8 [temp2]=r11,16	// cr.iipa
499	mov r12=cr.iim
500	;;
501	st8 [temp1]=r12		// cr.iim
502(p1)	mov r12=IA64_MCA_COLD_BOOT
503(p2)	mov r12=IA64_INIT_WARM_BOOT
504	mov r6=cr.iha
505	add temp1=SOS(OS_STATUS), regs
506	;;
507	st8 [temp2]=r6		// cr.iha
508	add temp2=SOS(CONTEXT), regs
509	st8 [temp1]=r12		// os_status, default is cold boot
510	mov r6=IA64_MCA_SAME_CONTEXT
511	;;
512	st8 [temp2]=r6		// context, default is same context
513
514	// Save the pt_regs data that is not in minstate.  The previous code
515	// left regs at sos.
516	add regs=MCA_PT_REGS_OFFSET-MCA_SOS_OFFSET, regs
517	;;
518	add temp1=PT(B6), regs
519	mov temp3=b6
520	mov temp4=b7
521	add temp2=PT(B7), regs
522	;;
523	st8 [temp1]=temp3,PT(AR_CSD)-PT(B6)		// save b6
524	st8 [temp2]=temp4,PT(AR_SSD)-PT(B7)		// save b7
525	mov temp3=ar.csd
526	mov temp4=ar.ssd
527	cover						// must be last in group
528	;;
529	st8 [temp1]=temp3,PT(AR_UNAT)-PT(AR_CSD)	// save ar.csd
530	st8 [temp2]=temp4,PT(AR_PFS)-PT(AR_SSD)		// save ar.ssd
531	mov temp3=ar.unat
532	mov temp4=ar.pfs
533	;;
534	st8 [temp1]=temp3,PT(AR_RNAT)-PT(AR_UNAT)	// save ar.unat
535	st8 [temp2]=temp4,PT(AR_BSPSTORE)-PT(AR_PFS)	// save ar.pfs
536	mov temp3=ar.rnat
537	mov temp4=ar.bspstore
538	;;
539	st8 [temp1]=temp3,PT(LOADRS)-PT(AR_RNAT)	// save ar.rnat
540	st8 [temp2]=temp4,PT(AR_FPSR)-PT(AR_BSPSTORE)	// save ar.bspstore
541	mov temp3=ar.bsp
542	;;
543	sub temp3=temp3, temp4	// ar.bsp - ar.bspstore
544	mov temp4=ar.fpsr
545	;;
546	shl temp3=temp3,16	// compute ar.rsc to be used for "loadrs"
547	;;
548	st8 [temp1]=temp3,PT(AR_CCV)-PT(LOADRS)		// save loadrs
549	st8 [temp2]=temp4,PT(F6)-PT(AR_FPSR)		// save ar.fpsr
550	mov temp3=ar.ccv
551	;;
552	st8 [temp1]=temp3,PT(F7)-PT(AR_CCV)		// save ar.ccv
553	stf.spill [temp2]=f6,PT(F8)-PT(F6)
554	;;
555	stf.spill [temp1]=f7,PT(F9)-PT(F7)
556	stf.spill [temp2]=f8,PT(F10)-PT(F8)
557	;;
558	stf.spill [temp1]=f9,PT(F11)-PT(F9)
559	stf.spill [temp2]=f10
560	;;
561	stf.spill [temp1]=f11
562
563	// Save the switch_stack data that is not in minstate nor pt_regs.  The
564	// previous code left regs at pt_regs.
565	add regs=MCA_SWITCH_STACK_OFFSET-MCA_PT_REGS_OFFSET, regs
566	;;
567	add temp1=SW(F2), regs
568	add temp2=SW(F3), regs
569	;;
570	stf.spill [temp1]=f2,32
571	stf.spill [temp2]=f3,32
572	;;
573	stf.spill [temp1]=f4,32
574	stf.spill [temp2]=f5,32
575	;;
576	stf.spill [temp1]=f12,32
577	stf.spill [temp2]=f13,32
578	;;
579	stf.spill [temp1]=f14,32
580	stf.spill [temp2]=f15,32
581	;;
582	stf.spill [temp1]=f16,32
583	stf.spill [temp2]=f17,32
584	;;
585	stf.spill [temp1]=f18,32
586	stf.spill [temp2]=f19,32
587	;;
588	stf.spill [temp1]=f20,32
589	stf.spill [temp2]=f21,32
590	;;
591	stf.spill [temp1]=f22,32
592	stf.spill [temp2]=f23,32
593	;;
594	stf.spill [temp1]=f24,32
595	stf.spill [temp2]=f25,32
596	;;
597	stf.spill [temp1]=f26,32
598	stf.spill [temp2]=f27,32
599	;;
600	stf.spill [temp1]=f28,32
601	stf.spill [temp2]=f29,32
602	;;
603	stf.spill [temp1]=f30,SW(B2)-SW(F30)
604	stf.spill [temp2]=f31,SW(B3)-SW(F31)
605	mov temp3=b2
606	mov temp4=b3
607	;;
608	st8 [temp1]=temp3,16	// save b2
609	st8 [temp2]=temp4,16	// save b3
610	mov temp3=b4
611	mov temp4=b5
612	;;
613	st8 [temp1]=temp3,SW(AR_LC)-SW(B4)	// save b4
614	st8 [temp2]=temp4	// save b5
615	mov temp3=ar.lc
616	;;
617	st8 [temp1]=temp3	// save ar.lc
618
619	// FIXME: Some proms are incorrectly accessing the minstate area as
620	// cached data.  The C code uses region 6, uncached virtual.  Ensure
621	// that there is no cache data lying around for the first 1K of the
622	// minstate area.
623	// Remove this code in September 2006, that gives platforms a year to
624	// fix their proms and get their customers updated.
625
626	add r1=32*1,r17
627	add r2=32*2,r17
628	add r3=32*3,r17
629	add r4=32*4,r17
630	add r5=32*5,r17
631	add r6=32*6,r17
632	add r7=32*7,r17
633	;;
634	fc r17
635	fc r1
636	fc r2
637	fc r3
638	fc r4
639	fc r5
640	fc r6
641	fc r7
642	add r17=32*8,r17
643	add r1=32*8,r1
644	add r2=32*8,r2
645	add r3=32*8,r3
646	add r4=32*8,r4
647	add r5=32*8,r5
648	add r6=32*8,r6
649	add r7=32*8,r7
650	;;
651	fc r17
652	fc r1
653	fc r2
654	fc r3
655	fc r4
656	fc r5
657	fc r6
658	fc r7
659	add r17=32*8,r17
660	add r1=32*8,r1
661	add r2=32*8,r2
662	add r3=32*8,r3
663	add r4=32*8,r4
664	add r5=32*8,r5
665	add r6=32*8,r6
666	add r7=32*8,r7
667	;;
668	fc r17
669	fc r1
670	fc r2
671	fc r3
672	fc r4
673	fc r5
674	fc r6
675	fc r7
676	add r17=32*8,r17
677	add r1=32*8,r1
678	add r2=32*8,r2
679	add r3=32*8,r3
680	add r4=32*8,r4
681	add r5=32*8,r5
682	add r6=32*8,r6
683	add r7=32*8,r7
684	;;
685	fc r17
686	fc r1
687	fc r2
688	fc r3
689	fc r4
690	fc r5
691	fc r6
692	fc r7
693
694	br.sptk b0
695
696//EndStub//////////////////////////////////////////////////////////////////////
697
698
699//++
700// Name:
701//	ia64_state_restore()
702//
703// Stub Description:
704//
705//	Restore the SAL/OS state.  This is sensitive to the layout of struct
706//	ia64_sal_os_state in mca.h.
707//
708//	r2 contains the return address, r3 contains either
709//	IA64_MCA_CPU_MCA_STACK_OFFSET or IA64_MCA_CPU_INIT_STACK_OFFSET.
710//
711//	In addition to the SAL to OS state, this routine restores all the
712//	registers that appear in struct pt_regs and struct switch_stack,
713//	excluding those in the PAL minstate area.
714//
715//--
716
717ia64_state_restore:
718	// Restore the switch_stack data that is not in minstate nor pt_regs.
719	add regs=MCA_SWITCH_STACK_OFFSET, r3
720	mov b0=r2		// save return address
721	;;
722	GET_IA64_MCA_DATA(temp2)
723	;;
724	add regs=temp2, regs
725	;;
726	add temp1=SW(F2), regs
727	add temp2=SW(F3), regs
728	;;
729	ldf.fill f2=[temp1],32
730	ldf.fill f3=[temp2],32
731	;;
732	ldf.fill f4=[temp1],32
733	ldf.fill f5=[temp2],32
734	;;
735	ldf.fill f12=[temp1],32
736	ldf.fill f13=[temp2],32
737	;;
738	ldf.fill f14=[temp1],32
739	ldf.fill f15=[temp2],32
740	;;
741	ldf.fill f16=[temp1],32
742	ldf.fill f17=[temp2],32
743	;;
744	ldf.fill f18=[temp1],32
745	ldf.fill f19=[temp2],32
746	;;
747	ldf.fill f20=[temp1],32
748	ldf.fill f21=[temp2],32
749	;;
750	ldf.fill f22=[temp1],32
751	ldf.fill f23=[temp2],32
752	;;
753	ldf.fill f24=[temp1],32
754	ldf.fill f25=[temp2],32
755	;;
756	ldf.fill f26=[temp1],32
757	ldf.fill f27=[temp2],32
758	;;
759	ldf.fill f28=[temp1],32
760	ldf.fill f29=[temp2],32
761	;;
762	ldf.fill f30=[temp1],SW(B2)-SW(F30)
763	ldf.fill f31=[temp2],SW(B3)-SW(F31)
764	;;
765	ld8 temp3=[temp1],16	// restore b2
766	ld8 temp4=[temp2],16	// restore b3
767	;;
768	mov b2=temp3
769	mov b3=temp4
770	ld8 temp3=[temp1],SW(AR_LC)-SW(B4)	// restore b4
771	ld8 temp4=[temp2]	// restore b5
772	;;
773	mov b4=temp3
774	mov b5=temp4
775	ld8 temp3=[temp1]	// restore ar.lc
776	;;
777	mov ar.lc=temp3
778
779	// Restore the pt_regs data that is not in minstate.  The previous code
780	// left regs at switch_stack.
781	add regs=MCA_PT_REGS_OFFSET-MCA_SWITCH_STACK_OFFSET, regs
782	;;
783	add temp1=PT(B6), regs
784	add temp2=PT(B7), regs
785	;;
786	ld8 temp3=[temp1],PT(AR_CSD)-PT(B6)		// restore b6
787	ld8 temp4=[temp2],PT(AR_SSD)-PT(B7)		// restore b7
788	;;
789	mov b6=temp3
790	mov b7=temp4
791	ld8 temp3=[temp1],PT(AR_UNAT)-PT(AR_CSD)	// restore ar.csd
792	ld8 temp4=[temp2],PT(AR_PFS)-PT(AR_SSD)		// restore ar.ssd
793	;;
794	mov ar.csd=temp3
795	mov ar.ssd=temp4
796	ld8 temp3=[temp1]				// restore ar.unat
797	add temp1=PT(AR_CCV)-PT(AR_UNAT), temp1
798	ld8 temp4=[temp2],PT(AR_FPSR)-PT(AR_PFS)	// restore ar.pfs
799	;;
800	mov ar.unat=temp3
801	mov ar.pfs=temp4
802	// ar.rnat, ar.bspstore, loadrs are restore in ia64_old_stack.
803	ld8 temp3=[temp1],PT(F6)-PT(AR_CCV)		// restore ar.ccv
804	ld8 temp4=[temp2],PT(F7)-PT(AR_FPSR)		// restore ar.fpsr
805	;;
806	mov ar.ccv=temp3
807	mov ar.fpsr=temp4
808	ldf.fill f6=[temp1],PT(F8)-PT(F6)
809	ldf.fill f7=[temp2],PT(F9)-PT(F7)
810	;;
811	ldf.fill f8=[temp1],PT(F10)-PT(F8)
812	ldf.fill f9=[temp2],PT(F11)-PT(F9)
813	;;
814	ldf.fill f10=[temp1]
815	ldf.fill f11=[temp2]
816
817	// Restore the SAL to OS state. The previous code left regs at pt_regs.
818	add regs=MCA_SOS_OFFSET-MCA_PT_REGS_OFFSET, regs
819	;;
820	add temp1=SOS(SAL_RA), regs
821	add temp2=SOS(SAL_GP), regs
822	;;
823	ld8 r12=[temp1],16	// sal_ra
824	ld8 r9=[temp2],16	// sal_gp
825	;;
826	ld8 r22=[temp1],16	// pal_min_state, virtual
827	ld8 r13=[temp2],16	// prev_IA64_KR_CURRENT
828	;;
829	ld8 r16=[temp1],16	// prev_IA64_KR_CURRENT_STACK
830	ld8 r20=[temp2],16	// prev_task
831	;;
832	ld8 temp3=[temp1],16	// cr.isr
833	ld8 temp4=[temp2],16	// cr.ifa
834	;;
835	mov cr.isr=temp3
836	mov cr.ifa=temp4
837	ld8 temp3=[temp1],16	// cr.itir
838	ld8 temp4=[temp2],16	// cr.iipa
839	;;
840	mov cr.itir=temp3
841	mov cr.iipa=temp4
842	ld8 temp3=[temp1]	// cr.iim
843	ld8 temp4=[temp2]		// cr.iha
844	add temp1=SOS(OS_STATUS), regs
845	add temp2=SOS(CONTEXT), regs
846	;;
847	mov cr.iim=temp3
848	mov cr.iha=temp4
849	dep r22=0,r22,62,1	// pal_min_state, physical, uncached
850	mov IA64_KR(CURRENT)=r13
851	ld8 r8=[temp1]		// os_status
852	ld8 r10=[temp2]		// context
853
854	/* Wire IA64_TR_CURRENT_STACK to the stack that we are resuming to.  To
855	 * avoid any dependencies on the algorithm in ia64_switch_to(), just
856	 * purge any existing CURRENT_STACK mapping and insert the new one.
857	 *
858	 * r16 contains prev_IA64_KR_CURRENT_STACK, r13 contains
859	 * prev_IA64_KR_CURRENT, these values may have been changed by the C
860	 * code.  Do not use r8, r9, r10, r22, they contain values ready for
861	 * the return to SAL.
862	 */
863
864	mov r15=IA64_KR(CURRENT_STACK)		// physical granule mapped by IA64_TR_CURRENT_STACK
865	;;
866	shl r15=r15,IA64_GRANULE_SHIFT
867	;;
868	dep r15=-1,r15,61,3			// virtual granule
869	mov r18=IA64_GRANULE_SHIFT<<2		// for cr.itir.ps
870	;;
871	ptr.d r15,r18
872	;;
873	srlz.d
874
875	extr.u r19=r13,61,3			// r13 = prev_IA64_KR_CURRENT
876	shl r20=r16,IA64_GRANULE_SHIFT		// r16 = prev_IA64_KR_CURRENT_STACK
877	movl r21=PAGE_KERNEL			// page properties
878	;;
879	mov IA64_KR(CURRENT_STACK)=r16
880	cmp.ne p6,p0=RGN_KERNEL,r19		// new stack is in the kernel region?
881	or r21=r20,r21				// construct PA | page properties
882(p6)	br.spnt 1f				// the dreaded cpu 0 idle task in region 5:(
883	;;
884	mov cr.itir=r18
885	mov cr.ifa=r13
886	mov r20=IA64_TR_CURRENT_STACK
887	;;
888	itr.d dtr[r20]=r21
889	;;
890	srlz.d
8911:
892
893	br.sptk b0
894
895//EndStub//////////////////////////////////////////////////////////////////////
896
897
898//++
899// Name:
900//	ia64_new_stack()
901//
902// Stub Description:
903//
904//	Switch to the MCA/INIT stack.
905//
906//	r2 contains the return address, r3 contains either
907//	IA64_MCA_CPU_MCA_STACK_OFFSET or IA64_MCA_CPU_INIT_STACK_OFFSET.
908//
909//	On entry RBS is still on the original stack, this routine switches RBS
910//	to use the MCA/INIT stack.
911//
912//	On entry, sos->pal_min_state is physical, on exit it is virtual.
913//
914//--
915
916ia64_new_stack:
917	add regs=MCA_PT_REGS_OFFSET, r3
918	add temp2=MCA_SOS_OFFSET+SOS(PAL_MIN_STATE), r3
919	mov b0=r2			// save return address
920	GET_IA64_MCA_DATA(temp1)
921	invala
922	;;
923	add temp2=temp2, temp1		// struct ia64_sal_os_state.pal_min_state on MCA or INIT stack
924	add regs=regs, temp1		// struct pt_regs on MCA or INIT stack
925	;;
926	// Address of minstate area provided by PAL is physical, uncacheable.
927	// Convert to Linux virtual address in region 6 for C code.
928	ld8 ms=[temp2]			// pal_min_state, physical
929	;;
930	dep temp1=-1,ms,62,2		// set region 6
931	mov temp3=IA64_RBS_OFFSET-MCA_PT_REGS_OFFSET
932	;;
933	st8 [temp2]=temp1		// pal_min_state, virtual
934
935	add temp4=temp3, regs		// start of bspstore on new stack
936	;;
937	mov ar.bspstore=temp4		// switch RBS to MCA/INIT stack
938	;;
939	flushrs				// must be first in group
940	br.sptk b0
941
942//EndStub//////////////////////////////////////////////////////////////////////
943
944
945//++
946// Name:
947//	ia64_old_stack()
948//
949// Stub Description:
950//
951//	Switch to the old stack.
952//
953//	r2 contains the return address, r3 contains either
954//	IA64_MCA_CPU_MCA_STACK_OFFSET or IA64_MCA_CPU_INIT_STACK_OFFSET.
955//
956//	On entry, pal_min_state is virtual, on exit it is physical.
957//
958//	On entry RBS is on the MCA/INIT stack, this routine switches RBS
959//	back to the previous stack.
960//
961//	The psr is set to all zeroes.  SAL return requires either all zeroes or
962//	just psr.mc set.  Leaving psr.mc off allows INIT to be issued if this
963//	code does not perform correctly.
964//
965//	The dirty registers at the time of the event were flushed to the
966//	MCA/INIT stack in ia64_pt_regs_save().  Restore the dirty registers
967//	before reverting to the previous bspstore.
968//--
969
970ia64_old_stack:
971	add regs=MCA_PT_REGS_OFFSET, r3
972	mov b0=r2			// save return address
973	GET_IA64_MCA_DATA(temp2)
974	LOAD_PHYSICAL(p0,temp1,1f)
975	;;
976	mov cr.ipsr=r0
977	mov cr.ifs=r0
978	mov cr.iip=temp1
979	;;
980	invala
981	rfi
9821:
983
984	add regs=regs, temp2		// struct pt_regs on MCA or INIT stack
985	;;
986	add temp1=PT(LOADRS), regs
987	;;
988	ld8 temp2=[temp1],PT(AR_BSPSTORE)-PT(LOADRS)	// restore loadrs
989	;;
990	ld8 temp3=[temp1],PT(AR_RNAT)-PT(AR_BSPSTORE)	// restore ar.bspstore
991	mov ar.rsc=temp2
992	;;
993	loadrs
994	ld8 temp4=[temp1]		// restore ar.rnat
995	;;
996	mov ar.bspstore=temp3		// back to old stack
997	;;
998	mov ar.rnat=temp4
999	;;
1000
1001	br.sptk b0
1002
1003//EndStub//////////////////////////////////////////////////////////////////////
1004
1005
1006//++
1007// Name:
1008//	ia64_set_kernel_registers()
1009//
1010// Stub Description:
1011//
1012//	Set the registers that are required by the C code in order to run on an
1013//	MCA/INIT stack.
1014//
1015//	r2 contains the return address, r3 contains either
1016//	IA64_MCA_CPU_MCA_STACK_OFFSET or IA64_MCA_CPU_INIT_STACK_OFFSET.
1017//
1018//--
1019
1020ia64_set_kernel_registers:
1021	add temp3=MCA_SP_OFFSET, r3
1022	mov b0=r2		// save return address
1023	GET_IA64_MCA_DATA(temp1)
1024	;;
1025	add r12=temp1, temp3	// kernel stack pointer on MCA/INIT stack
1026	add r13=temp1, r3	// set current to start of MCA/INIT stack
1027	add r20=temp1, r3	// physical start of MCA/INIT stack
1028	;;
1029	DATA_PA_TO_VA(r12,temp2)
1030	DATA_PA_TO_VA(r13,temp3)
1031	;;
1032	mov IA64_KR(CURRENT)=r13
1033
1034	/* Wire IA64_TR_CURRENT_STACK to the MCA/INIT handler stack.  To avoid
1035	 * any dependencies on the algorithm in ia64_switch_to(), just purge
1036	 * any existing CURRENT_STACK mapping and insert the new one.
1037	 */
1038
1039	mov r16=IA64_KR(CURRENT_STACK)		// physical granule mapped by IA64_TR_CURRENT_STACK
1040	;;
1041	shl r16=r16,IA64_GRANULE_SHIFT
1042	;;
1043	dep r16=-1,r16,61,3			// virtual granule
1044	mov r18=IA64_GRANULE_SHIFT<<2		// for cr.itir.ps
1045	;;
1046	ptr.d r16,r18
1047	;;
1048	srlz.d
1049
1050	shr.u r16=r20,IA64_GRANULE_SHIFT	// r20 = physical start of MCA/INIT stack
1051	movl r21=PAGE_KERNEL			// page properties
1052	;;
1053	mov IA64_KR(CURRENT_STACK)=r16
1054	or r21=r20,r21				// construct PA | page properties
1055	;;
1056	mov cr.itir=r18
1057	mov cr.ifa=r13
1058	mov r20=IA64_TR_CURRENT_STACK
1059
1060	movl r17=FPSR_DEFAULT
1061	;;
1062	mov.m ar.fpsr=r17			// set ar.fpsr to kernel default value
1063	;;
1064	itr.d dtr[r20]=r21
1065	;;
1066	srlz.d
1067
1068	br.sptk b0
1069
1070//EndStub//////////////////////////////////////////////////////////////////////
1071
1072#undef	ms
1073#undef	regs
1074#undef	temp1
1075#undef	temp2
1076#undef	temp3
1077#undef	temp4
1078
1079
1080// Support function for mca.c, it is here to avoid using inline asm.  Given the
1081// address of an rnat slot, if that address is below the current ar.bspstore
1082// then return the contents of that slot, otherwise return the contents of
1083// ar.rnat.
1084GLOBAL_ENTRY(ia64_get_rnat)
1085	alloc r14=ar.pfs,1,0,0,0
1086	mov ar.rsc=0
1087	;;
1088	mov r14=ar.bspstore
1089	;;
1090	cmp.lt p6,p7=in0,r14
1091	;;
1092(p6)	ld8 r8=[in0]
1093(p7)	mov r8=ar.rnat
1094	mov ar.rsc=3
1095	br.ret.sptk.many rp
1096END(ia64_get_rnat)
1097
1098
1099// void ia64_set_psr_mc(void)
1100//
1101// Set psr.mc bit to mask MCA/INIT.
1102GLOBAL_ENTRY(ia64_set_psr_mc)
1103	rsm psr.i | psr.ic		// disable interrupts
1104	;;
1105	srlz.d
1106	;;
1107	mov r14 = psr			// get psr{36:35,31:0}
1108	movl r15 = 1f
1109	;;
1110	dep r14 = -1, r14, PSR_MC, 1	// set psr.mc
1111	;;
1112	dep r14 = -1, r14, PSR_IC, 1	// set psr.ic
1113	;;
1114	dep r14 = -1, r14, PSR_BN, 1	// keep bank1 in use
1115	;;
1116	mov cr.ipsr = r14
1117	mov cr.ifs = r0
1118	mov cr.iip = r15
1119	;;
1120	rfi
11211:
1122	br.ret.sptk.many rp
1123END(ia64_set_psr_mc)
1124