xref: /linux/arch/powerpc/kernel/head_64.S (revision 6176aa9ae4b83e1957d3031774f8a8e59ff97420)
1/*
2 *  arch/ppc64/kernel/head.S
3 *
4 *  PowerPC version
5 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
6 *
7 *  Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
8 *    Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
9 *  Adapted for Power Macintosh by Paul Mackerras.
10 *  Low-level exception handlers and MMU support
11 *  rewritten by Paul Mackerras.
12 *    Copyright (C) 1996 Paul Mackerras.
13 *
14 *  Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
15 *    Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
16 *
17 *  This file contains the low-level support and setup for the
18 *  PowerPC-64 platform, including trap and interrupt dispatch.
19 *
20 *  This program is free software; you can redistribute it and/or
21 *  modify it under the terms of the GNU General Public License
22 *  as published by the Free Software Foundation; either version
23 *  2 of the License, or (at your option) any later version.
24 */
25
26#include <linux/config.h>
27#include <linux/threads.h>
28#include <asm/reg.h>
29#include <asm/page.h>
30#include <asm/mmu.h>
31#include <asm/ppc_asm.h>
32#include <asm/asm-offsets.h>
33#include <asm/bug.h>
34#include <asm/cputable.h>
35#include <asm/setup.h>
36#include <asm/hvcall.h>
37#include <asm/iseries/lpar_map.h>
38#include <asm/thread_info.h>
39
40#ifdef CONFIG_PPC_ISERIES
41#define DO_SOFT_DISABLE
42#endif
43
44/*
45 * We layout physical memory as follows:
46 * 0x0000 - 0x00ff : Secondary processor spin code
47 * 0x0100 - 0x2fff : pSeries Interrupt prologs
48 * 0x3000 - 0x5fff : interrupt support, iSeries and common interrupt prologs
49 * 0x6000 - 0x6fff : Initial (CPU0) segment table
50 * 0x7000 - 0x7fff : FWNMI data area
51 * 0x8000 -        : Early init and support code
52 */
53
54/*
55 *   SPRG Usage
56 *
57 *   Register	Definition
58 *
59 *   SPRG0	reserved for hypervisor
60 *   SPRG1	temp - used to save gpr
61 *   SPRG2	temp - used to save gpr
62 *   SPRG3	virt addr of paca
63 */
64
65/*
66 * Entering into this code we make the following assumptions:
67 *  For pSeries:
68 *   1. The MMU is off & open firmware is running in real mode.
69 *   2. The kernel is entered at __start
70 *
71 *  For iSeries:
72 *   1. The MMU is on (as it always is for iSeries)
73 *   2. The kernel is entered at system_reset_iSeries
74 */
75
76	.text
77	.globl  _stext
78_stext:
79#ifdef CONFIG_PPC_MULTIPLATFORM
80_GLOBAL(__start)
81	/* NOP this out unconditionally */
82BEGIN_FTR_SECTION
83	b	.__start_initialization_multiplatform
84END_FTR_SECTION(0, 1)
85#endif /* CONFIG_PPC_MULTIPLATFORM */
86
87	/* Catch branch to 0 in real mode */
88	trap
89
90#ifdef CONFIG_PPC_ISERIES
91	/*
92	 * At offset 0x20, there is a pointer to iSeries LPAR data.
93	 * This is required by the hypervisor
94	 */
95	. = 0x20
96	.llong hvReleaseData-KERNELBASE
97
98	/*
99	 * At offset 0x28 and 0x30 are offsets to the mschunks_map
100	 * array (used by the iSeries LPAR debugger to do translation
101	 * between physical addresses and absolute addresses) and
102	 * to the pidhash table (also used by the debugger)
103	 */
104	.llong mschunks_map-KERNELBASE
105	.llong 0	/* pidhash-KERNELBASE SFRXXX */
106
107	/* Offset 0x38 - Pointer to start of embedded System.map */
108	.globl	embedded_sysmap_start
109embedded_sysmap_start:
110	.llong	0
111	/* Offset 0x40 - Pointer to end of embedded System.map */
112	.globl	embedded_sysmap_end
113embedded_sysmap_end:
114	.llong	0
115
116#endif /* CONFIG_PPC_ISERIES */
117
118	/* Secondary processors spin on this value until it goes to 1. */
119	.globl  __secondary_hold_spinloop
120__secondary_hold_spinloop:
121	.llong	0x0
122
123	/* Secondary processors write this value with their cpu # */
124	/* after they enter the spin loop immediately below.	  */
125	.globl	__secondary_hold_acknowledge
126__secondary_hold_acknowledge:
127	.llong	0x0
128
129	. = 0x60
130/*
131 * The following code is used on pSeries to hold secondary processors
132 * in a spin loop after they have been freed from OpenFirmware, but
133 * before the bulk of the kernel has been relocated.  This code
134 * is relocated to physical address 0x60 before prom_init is run.
135 * All of it must fit below the first exception vector at 0x100.
136 */
137_GLOBAL(__secondary_hold)
138	mfmsr	r24
139	ori	r24,r24,MSR_RI
140	mtmsrd	r24			/* RI on */
141
142	/* Grab our linux cpu number */
143	mr	r24,r3
144
145	/* Tell the master cpu we're here */
146	/* Relocation is off & we are located at an address less */
147	/* than 0x100, so only need to grab low order offset.    */
148	std	r24,__secondary_hold_acknowledge@l(0)
149	sync
150
151	/* All secondary cpus wait here until told to start. */
152100:	ld	r4,__secondary_hold_spinloop@l(0)
153	cmpdi	0,r4,1
154	bne	100b
155
156#ifdef CONFIG_HMT
157	SET_REG_IMMEDIATE(r4, .hmt_init)
158	mtctr	r4
159	bctr
160#else
161#ifdef CONFIG_SMP
162	LOAD_REG_IMMEDIATE(r4, .pSeries_secondary_smp_init)
163	mtctr	r4
164	mr	r3,r24
165	bctr
166#else
167	BUG_OPCODE
168#endif
169#endif
170
171/* This value is used to mark exception frames on the stack. */
172	.section ".toc","aw"
173exception_marker:
174	.tc	ID_72656773_68657265[TC],0x7265677368657265
175	.text
176
177/*
178 * The following macros define the code that appears as
179 * the prologue to each of the exception handlers.  They
180 * are split into two parts to allow a single kernel binary
181 * to be used for pSeries and iSeries.
182 * LOL.  One day... - paulus
183 */
184
185/*
186 * We make as much of the exception code common between native
187 * exception handlers (including pSeries LPAR) and iSeries LPAR
188 * implementations as possible.
189 */
190
191/*
192 * This is the start of the interrupt handlers for pSeries
193 * This code runs with relocation off.
194 */
195#define EX_R9		0
196#define EX_R10		8
197#define EX_R11		16
198#define EX_R12		24
199#define EX_R13		32
200#define EX_SRR0		40
201#define EX_DAR		48
202#define EX_DSISR	56
203#define EX_CCR		60
204#define EX_R3		64
205#define EX_LR		72
206
207/*
208 * We're short on space and time in the exception prolog, so we can't
209 * use the normal SET_REG_IMMEDIATE macro. Normally we just need the
210 * low halfword of the address, but for Kdump we need the whole low
211 * word.
212 */
213#ifdef CONFIG_CRASH_DUMP
214#define LOAD_HANDLER(reg, label)					\
215	oris	reg,reg,(label)@h;	/* virt addr of handler ... */	\
216	ori	reg,reg,(label)@l;	/* .. and the rest */
217#else
218#define LOAD_HANDLER(reg, label)					\
219	ori	reg,reg,(label)@l;	/* virt addr of handler ... */
220#endif
221
222#define EXCEPTION_PROLOG_PSERIES(area, label)				\
223	mfspr	r13,SPRN_SPRG3;		/* get paca address into r13 */	\
224	std	r9,area+EX_R9(r13);	/* save r9 - r12 */		\
225	std	r10,area+EX_R10(r13);					\
226	std	r11,area+EX_R11(r13);					\
227	std	r12,area+EX_R12(r13);					\
228	mfspr	r9,SPRN_SPRG1;						\
229	std	r9,area+EX_R13(r13);					\
230	mfcr	r9;							\
231	clrrdi	r12,r13,32;		/* get high part of &label */	\
232	mfmsr	r10;							\
233	mfspr	r11,SPRN_SRR0;		/* save SRR0 */			\
234	LOAD_HANDLER(r12,label)						\
235	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI;				\
236	mtspr	SPRN_SRR0,r12;						\
237	mfspr	r12,SPRN_SRR1;		/* and SRR1 */			\
238	mtspr	SPRN_SRR1,r10;						\
239	rfid;								\
240	b	.	/* prevent speculative execution */
241
242/*
243 * This is the start of the interrupt handlers for iSeries
244 * This code runs with relocation on.
245 */
246#define EXCEPTION_PROLOG_ISERIES_1(area)				\
247	mfspr	r13,SPRN_SPRG3;		/* get paca address into r13 */	\
248	std	r9,area+EX_R9(r13);	/* save r9 - r12 */		\
249	std	r10,area+EX_R10(r13);					\
250	std	r11,area+EX_R11(r13);					\
251	std	r12,area+EX_R12(r13);					\
252	mfspr	r9,SPRN_SPRG1;						\
253	std	r9,area+EX_R13(r13);					\
254	mfcr	r9
255
256#define EXCEPTION_PROLOG_ISERIES_2					\
257	mfmsr	r10;							\
258	ld	r12,PACALPPACAPTR(r13);					\
259	ld	r11,LPPACASRR0(r12);					\
260	ld	r12,LPPACASRR1(r12);					\
261	ori	r10,r10,MSR_RI;						\
262	mtmsrd	r10,1
263
264/*
265 * The common exception prolog is used for all except a few exceptions
266 * such as a segment miss on a kernel address.  We have to be prepared
267 * to take another exception from the point where we first touch the
268 * kernel stack onwards.
269 *
270 * On entry r13 points to the paca, r9-r13 are saved in the paca,
271 * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
272 * SRR1, and relocation is on.
273 */
274#define EXCEPTION_PROLOG_COMMON(n, area)				   \
275	andi.	r10,r12,MSR_PR;		/* See if coming from user	*/ \
276	mr	r10,r1;			/* Save r1			*/ \
277	subi	r1,r1,INT_FRAME_SIZE;	/* alloc frame on kernel stack	*/ \
278	beq-	1f;							   \
279	ld	r1,PACAKSAVE(r13);	/* kernel stack to use		*/ \
2801:	cmpdi	cr1,r1,0;		/* check if r1 is in userspace	*/ \
281	bge-	cr1,bad_stack;		/* abort if it is		*/ \
282	std	r9,_CCR(r1);		/* save CR in stackframe	*/ \
283	std	r11,_NIP(r1);		/* save SRR0 in stackframe	*/ \
284	std	r12,_MSR(r1);		/* save SRR1 in stackframe	*/ \
285	std	r10,0(r1);		/* make stack chain pointer	*/ \
286	std	r0,GPR0(r1);		/* save r0 in stackframe	*/ \
287	std	r10,GPR1(r1);		/* save r1 in stackframe	*/ \
288	std	r2,GPR2(r1);		/* save r2 in stackframe	*/ \
289	SAVE_4GPRS(3, r1);		/* save r3 - r6 in stackframe	*/ \
290	SAVE_2GPRS(7, r1);		/* save r7, r8 in stackframe	*/ \
291	ld	r9,area+EX_R9(r13);	/* move r9, r10 to stackframe	*/ \
292	ld	r10,area+EX_R10(r13);					   \
293	std	r9,GPR9(r1);						   \
294	std	r10,GPR10(r1);						   \
295	ld	r9,area+EX_R11(r13);	/* move r11 - r13 to stackframe	*/ \
296	ld	r10,area+EX_R12(r13);					   \
297	ld	r11,area+EX_R13(r13);					   \
298	std	r9,GPR11(r1);						   \
299	std	r10,GPR12(r1);						   \
300	std	r11,GPR13(r1);						   \
301	ld	r2,PACATOC(r13);	/* get kernel TOC into r2	*/ \
302	mflr	r9;			/* save LR in stackframe	*/ \
303	std	r9,_LINK(r1);						   \
304	mfctr	r10;			/* save CTR in stackframe	*/ \
305	std	r10,_CTR(r1);						   \
306	mfspr	r11,SPRN_XER;		/* save XER in stackframe	*/ \
307	std	r11,_XER(r1);						   \
308	li	r9,(n)+1;						   \
309	std	r9,_TRAP(r1);		/* set trap number		*/ \
310	li	r10,0;							   \
311	ld	r11,exception_marker@toc(r2);				   \
312	std	r10,RESULT(r1);		/* clear regs->result		*/ \
313	std	r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame	*/
314
315/*
316 * Exception vectors.
317 */
318#define STD_EXCEPTION_PSERIES(n, label)			\
319	. = n;						\
320	.globl label##_pSeries;				\
321label##_pSeries:					\
322	HMT_MEDIUM;					\
323	mtspr	SPRN_SPRG1,r13;		/* save r13 */	\
324	RUNLATCH_ON(r13);				\
325	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common)
326
327#define STD_EXCEPTION_ISERIES(n, label, area)		\
328	.globl label##_iSeries;				\
329label##_iSeries:					\
330	HMT_MEDIUM;					\
331	mtspr	SPRN_SPRG1,r13;		/* save r13 */	\
332	RUNLATCH_ON(r13);				\
333	EXCEPTION_PROLOG_ISERIES_1(area);		\
334	EXCEPTION_PROLOG_ISERIES_2;			\
335	b	label##_common
336
337#define MASKABLE_EXCEPTION_ISERIES(n, label)				\
338	.globl label##_iSeries;						\
339label##_iSeries:							\
340	HMT_MEDIUM;							\
341	mtspr	SPRN_SPRG1,r13;		/* save r13 */			\
342	RUNLATCH_ON(r13);						\
343	EXCEPTION_PROLOG_ISERIES_1(PACA_EXGEN);				\
344	lbz	r10,PACAPROCENABLED(r13);				\
345	cmpwi	0,r10,0;						\
346	beq-	label##_iSeries_masked;					\
347	EXCEPTION_PROLOG_ISERIES_2;					\
348	b	label##_common;						\
349
350#ifdef DO_SOFT_DISABLE
351#define DISABLE_INTS				\
352	lbz	r10,PACAPROCENABLED(r13);	\
353	li	r11,0;				\
354	std	r10,SOFTE(r1);			\
355	mfmsr	r10;				\
356	stb	r11,PACAPROCENABLED(r13);	\
357	ori	r10,r10,MSR_EE;			\
358	mtmsrd	r10,1
359
360#define ENABLE_INTS				\
361	lbz	r10,PACAPROCENABLED(r13);	\
362	mfmsr	r11;				\
363	std	r10,SOFTE(r1);			\
364	ori	r11,r11,MSR_EE;			\
365	mtmsrd	r11,1
366
367#else	/* hard enable/disable interrupts */
368#define DISABLE_INTS
369
370#define ENABLE_INTS				\
371	ld	r12,_MSR(r1);			\
372	mfmsr	r11;				\
373	rlwimi	r11,r12,0,MSR_EE;		\
374	mtmsrd	r11,1
375
376#endif
377
378#define STD_EXCEPTION_COMMON(trap, label, hdlr)		\
379	.align	7;					\
380	.globl label##_common;				\
381label##_common:						\
382	EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);	\
383	DISABLE_INTS;					\
384	bl	.save_nvgprs;				\
385	addi	r3,r1,STACK_FRAME_OVERHEAD;		\
386	bl	hdlr;					\
387	b	.ret_from_except
388
389#define STD_EXCEPTION_COMMON_LITE(trap, label, hdlr)	\
390	.align	7;					\
391	.globl label##_common;				\
392label##_common:						\
393	EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);	\
394	DISABLE_INTS;					\
395	addi	r3,r1,STACK_FRAME_OVERHEAD;		\
396	bl	hdlr;					\
397	b	.ret_from_except_lite
398
399/*
400 * Start of pSeries system interrupt routines
401 */
402	. = 0x100
403	.globl __start_interrupts
404__start_interrupts:
405
406	STD_EXCEPTION_PSERIES(0x100, system_reset)
407
408	. = 0x200
409_machine_check_pSeries:
410	HMT_MEDIUM
411	mtspr	SPRN_SPRG1,r13		/* save r13 */
412	RUNLATCH_ON(r13)
413	EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common)
414
415	. = 0x300
416	.globl data_access_pSeries
417data_access_pSeries:
418	HMT_MEDIUM
419	mtspr	SPRN_SPRG1,r13
420BEGIN_FTR_SECTION
421	mtspr	SPRN_SPRG2,r12
422	mfspr	r13,SPRN_DAR
423	mfspr	r12,SPRN_DSISR
424	srdi	r13,r13,60
425	rlwimi	r13,r12,16,0x20
426	mfcr	r12
427	cmpwi	r13,0x2c
428	beq	.do_stab_bolted_pSeries
429	mtcrf	0x80,r12
430	mfspr	r12,SPRN_SPRG2
431END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
432	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common)
433
434	. = 0x380
435	.globl data_access_slb_pSeries
436data_access_slb_pSeries:
437	HMT_MEDIUM
438	mtspr	SPRN_SPRG1,r13
439	RUNLATCH_ON(r13)
440	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
441	std	r3,PACA_EXSLB+EX_R3(r13)
442	mfspr	r3,SPRN_DAR
443	std	r9,PACA_EXSLB+EX_R9(r13)	/* save r9 - r12 */
444	mfcr	r9
445#ifdef __DISABLED__
446	/* Keep that around for when we re-implement dynamic VSIDs */
447	cmpdi	r3,0
448	bge	slb_miss_user_pseries
449#endif /* __DISABLED__ */
450	std	r10,PACA_EXSLB+EX_R10(r13)
451	std	r11,PACA_EXSLB+EX_R11(r13)
452	std	r12,PACA_EXSLB+EX_R12(r13)
453	mfspr	r10,SPRN_SPRG1
454	std	r10,PACA_EXSLB+EX_R13(r13)
455	mfspr	r12,SPRN_SRR1		/* and SRR1 */
456	b	.slb_miss_realmode	/* Rel. branch works in real mode */
457
458	STD_EXCEPTION_PSERIES(0x400, instruction_access)
459
460	. = 0x480
461	.globl instruction_access_slb_pSeries
462instruction_access_slb_pSeries:
463	HMT_MEDIUM
464	mtspr	SPRN_SPRG1,r13
465	RUNLATCH_ON(r13)
466	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
467	std	r3,PACA_EXSLB+EX_R3(r13)
468	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
469	std	r9,PACA_EXSLB+EX_R9(r13)	/* save r9 - r12 */
470	mfcr	r9
471#ifdef __DISABLED__
472	/* Keep that around for when we re-implement dynamic VSIDs */
473	cmpdi	r3,0
474	bge	slb_miss_user_pseries
475#endif /* __DISABLED__ */
476	std	r10,PACA_EXSLB+EX_R10(r13)
477	std	r11,PACA_EXSLB+EX_R11(r13)
478	std	r12,PACA_EXSLB+EX_R12(r13)
479	mfspr	r10,SPRN_SPRG1
480	std	r10,PACA_EXSLB+EX_R13(r13)
481	mfspr	r12,SPRN_SRR1		/* and SRR1 */
482	b	.slb_miss_realmode	/* Rel. branch works in real mode */
483
484	STD_EXCEPTION_PSERIES(0x500, hardware_interrupt)
485	STD_EXCEPTION_PSERIES(0x600, alignment)
486	STD_EXCEPTION_PSERIES(0x700, program_check)
487	STD_EXCEPTION_PSERIES(0x800, fp_unavailable)
488	STD_EXCEPTION_PSERIES(0x900, decrementer)
489	STD_EXCEPTION_PSERIES(0xa00, trap_0a)
490	STD_EXCEPTION_PSERIES(0xb00, trap_0b)
491
492	. = 0xc00
493	.globl	system_call_pSeries
494system_call_pSeries:
495	HMT_MEDIUM
496	RUNLATCH_ON(r9)
497	mr	r9,r13
498	mfmsr	r10
499	mfspr	r13,SPRN_SPRG3
500	mfspr	r11,SPRN_SRR0
501	clrrdi	r12,r13,32
502	oris	r12,r12,system_call_common@h
503	ori	r12,r12,system_call_common@l
504	mtspr	SPRN_SRR0,r12
505	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI
506	mfspr	r12,SPRN_SRR1
507	mtspr	SPRN_SRR1,r10
508	rfid
509	b	.	/* prevent speculative execution */
510
511	STD_EXCEPTION_PSERIES(0xd00, single_step)
512	STD_EXCEPTION_PSERIES(0xe00, trap_0e)
513
514	/* We need to deal with the Altivec unavailable exception
515	 * here which is at 0xf20, thus in the middle of the
516	 * prolog code of the PerformanceMonitor one. A little
517	 * trickery is thus necessary
518	 */
519	. = 0xf00
520	b	performance_monitor_pSeries
521
522	STD_EXCEPTION_PSERIES(0xf20, altivec_unavailable)
523
524	STD_EXCEPTION_PSERIES(0x1300, instruction_breakpoint)
525	STD_EXCEPTION_PSERIES(0x1700, altivec_assist)
526
527	. = 0x3000
528
529/*** pSeries interrupt support ***/
530
531	/* moved from 0xf00 */
532	STD_EXCEPTION_PSERIES(., performance_monitor)
533
534	.align	7
535_GLOBAL(do_stab_bolted_pSeries)
536	mtcrf	0x80,r12
537	mfspr	r12,SPRN_SPRG2
538	EXCEPTION_PROLOG_PSERIES(PACA_EXSLB, .do_stab_bolted)
539
540/*
541 * We have some room here  we use that to put
542 * the peries slb miss user trampoline code so it's reasonably
543 * away from slb_miss_user_common to avoid problems with rfid
544 *
545 * This is used for when the SLB miss handler has to go virtual,
546 * which doesn't happen for now anymore but will once we re-implement
547 * dynamic VSIDs for shared page tables
548 */
549#ifdef __DISABLED__
550slb_miss_user_pseries:
551	std	r10,PACA_EXGEN+EX_R10(r13)
552	std	r11,PACA_EXGEN+EX_R11(r13)
553	std	r12,PACA_EXGEN+EX_R12(r13)
554	mfspr	r10,SPRG1
555	ld	r11,PACA_EXSLB+EX_R9(r13)
556	ld	r12,PACA_EXSLB+EX_R3(r13)
557	std	r10,PACA_EXGEN+EX_R13(r13)
558	std	r11,PACA_EXGEN+EX_R9(r13)
559	std	r12,PACA_EXGEN+EX_R3(r13)
560	clrrdi	r12,r13,32
561	mfmsr	r10
562	mfspr	r11,SRR0			/* save SRR0 */
563	ori	r12,r12,slb_miss_user_common@l	/* virt addr of handler */
564	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI
565	mtspr	SRR0,r12
566	mfspr	r12,SRR1			/* and SRR1 */
567	mtspr	SRR1,r10
568	rfid
569	b	.				/* prevent spec. execution */
570#endif /* __DISABLED__ */
571
572/*
573 * Vectors for the FWNMI option.  Share common code.
574 */
575	.globl system_reset_fwnmi
576      .align 7
577system_reset_fwnmi:
578	HMT_MEDIUM
579	mtspr	SPRN_SPRG1,r13		/* save r13 */
580	RUNLATCH_ON(r13)
581	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common)
582
583	.globl machine_check_fwnmi
584      .align 7
585machine_check_fwnmi:
586	HMT_MEDIUM
587	mtspr	SPRN_SPRG1,r13		/* save r13 */
588	RUNLATCH_ON(r13)
589	EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common)
590
591#ifdef CONFIG_PPC_ISERIES
592/***  ISeries-LPAR interrupt handlers ***/
593
594	STD_EXCEPTION_ISERIES(0x200, machine_check, PACA_EXMC)
595
596	.globl data_access_iSeries
597data_access_iSeries:
598	mtspr	SPRN_SPRG1,r13
599BEGIN_FTR_SECTION
600	mtspr	SPRN_SPRG2,r12
601	mfspr	r13,SPRN_DAR
602	mfspr	r12,SPRN_DSISR
603	srdi	r13,r13,60
604	rlwimi	r13,r12,16,0x20
605	mfcr	r12
606	cmpwi	r13,0x2c
607	beq	.do_stab_bolted_iSeries
608	mtcrf	0x80,r12
609	mfspr	r12,SPRN_SPRG2
610END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
611	EXCEPTION_PROLOG_ISERIES_1(PACA_EXGEN)
612	EXCEPTION_PROLOG_ISERIES_2
613	b	data_access_common
614
615.do_stab_bolted_iSeries:
616	mtcrf	0x80,r12
617	mfspr	r12,SPRN_SPRG2
618	EXCEPTION_PROLOG_ISERIES_1(PACA_EXSLB)
619	EXCEPTION_PROLOG_ISERIES_2
620	b	.do_stab_bolted
621
622	.globl	data_access_slb_iSeries
623data_access_slb_iSeries:
624	mtspr	SPRN_SPRG1,r13		/* save r13 */
625	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
626	std	r3,PACA_EXSLB+EX_R3(r13)
627	mfspr	r3,SPRN_DAR
628	std	r9,PACA_EXSLB+EX_R9(r13)
629	mfcr	r9
630#ifdef __DISABLED__
631	cmpdi	r3,0
632	bge	slb_miss_user_iseries
633#endif
634	std	r10,PACA_EXSLB+EX_R10(r13)
635	std	r11,PACA_EXSLB+EX_R11(r13)
636	std	r12,PACA_EXSLB+EX_R12(r13)
637	mfspr	r10,SPRN_SPRG1
638	std	r10,PACA_EXSLB+EX_R13(r13)
639	ld	r12,PACALPPACAPTR(r13)
640	ld	r12,LPPACASRR1(r12)
641	b	.slb_miss_realmode
642
643	STD_EXCEPTION_ISERIES(0x400, instruction_access, PACA_EXGEN)
644
645	.globl	instruction_access_slb_iSeries
646instruction_access_slb_iSeries:
647	mtspr	SPRN_SPRG1,r13		/* save r13 */
648	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
649	std	r3,PACA_EXSLB+EX_R3(r13)
650	ld	r3,PACALPPACAPTR(r13)
651	ld	r3,LPPACASRR0(r3)	/* get SRR0 value */
652	std	r9,PACA_EXSLB+EX_R9(r13)
653	mfcr	r9
654#ifdef __DISABLED__
655	cmpdi	r3,0
656	bge	.slb_miss_user_iseries
657#endif
658	std	r10,PACA_EXSLB+EX_R10(r13)
659	std	r11,PACA_EXSLB+EX_R11(r13)
660	std	r12,PACA_EXSLB+EX_R12(r13)
661	mfspr	r10,SPRN_SPRG1
662	std	r10,PACA_EXSLB+EX_R13(r13)
663	ld	r12,PACALPPACAPTR(r13)
664	ld	r12,LPPACASRR1(r12)
665	b	.slb_miss_realmode
666
667#ifdef __DISABLED__
668slb_miss_user_iseries:
669	std	r10,PACA_EXGEN+EX_R10(r13)
670	std	r11,PACA_EXGEN+EX_R11(r13)
671	std	r12,PACA_EXGEN+EX_R12(r13)
672	mfspr	r10,SPRG1
673	ld	r11,PACA_EXSLB+EX_R9(r13)
674	ld	r12,PACA_EXSLB+EX_R3(r13)
675	std	r10,PACA_EXGEN+EX_R13(r13)
676	std	r11,PACA_EXGEN+EX_R9(r13)
677	std	r12,PACA_EXGEN+EX_R3(r13)
678	EXCEPTION_PROLOG_ISERIES_2
679	b	slb_miss_user_common
680#endif
681
682	MASKABLE_EXCEPTION_ISERIES(0x500, hardware_interrupt)
683	STD_EXCEPTION_ISERIES(0x600, alignment, PACA_EXGEN)
684	STD_EXCEPTION_ISERIES(0x700, program_check, PACA_EXGEN)
685	STD_EXCEPTION_ISERIES(0x800, fp_unavailable, PACA_EXGEN)
686	MASKABLE_EXCEPTION_ISERIES(0x900, decrementer)
687	STD_EXCEPTION_ISERIES(0xa00, trap_0a, PACA_EXGEN)
688	STD_EXCEPTION_ISERIES(0xb00, trap_0b, PACA_EXGEN)
689
690	.globl	system_call_iSeries
691system_call_iSeries:
692	mr	r9,r13
693	mfspr	r13,SPRN_SPRG3
694	EXCEPTION_PROLOG_ISERIES_2
695	b	system_call_common
696
697	STD_EXCEPTION_ISERIES( 0xd00, single_step, PACA_EXGEN)
698	STD_EXCEPTION_ISERIES( 0xe00, trap_0e, PACA_EXGEN)
699	STD_EXCEPTION_ISERIES( 0xf00, performance_monitor, PACA_EXGEN)
700
701	.globl system_reset_iSeries
702system_reset_iSeries:
703	mfspr	r13,SPRN_SPRG3		/* Get paca address */
704	mfmsr	r24
705	ori	r24,r24,MSR_RI
706	mtmsrd	r24			/* RI on */
707	lhz	r24,PACAPACAINDEX(r13)	/* Get processor # */
708	cmpwi	0,r24,0			/* Are we processor 0? */
709	beq	.__start_initialization_iSeries	/* Start up the first processor */
710	mfspr	r4,SPRN_CTRLF
711	li	r5,CTRL_RUNLATCH	/* Turn off the run light */
712	andc	r4,r4,r5
713	mtspr	SPRN_CTRLT,r4
714
7151:
716	HMT_LOW
717#ifdef CONFIG_SMP
718	lbz	r23,PACAPROCSTART(r13)	/* Test if this processor
719					 * should start */
720	sync
721	LOAD_REG_IMMEDIATE(r3,current_set)
722	sldi	r28,r24,3		/* get current_set[cpu#] */
723	ldx	r3,r3,r28
724	addi	r1,r3,THREAD_SIZE
725	subi	r1,r1,STACK_FRAME_OVERHEAD
726
727	cmpwi	0,r23,0
728	beq	iSeries_secondary_smp_loop	/* Loop until told to go */
729	bne	.__secondary_start		/* Loop until told to go */
730iSeries_secondary_smp_loop:
731	/* Let the Hypervisor know we are alive */
732	/* 8002 is a call to HvCallCfg::getLps, a harmless Hypervisor function */
733	lis	r3,0x8002
734	rldicr	r3,r3,32,15		/* r0 = (r3 << 32) & 0xffff000000000000 */
735#else /* CONFIG_SMP */
736	/* Yield the processor.  This is required for non-SMP kernels
737		which are running on multi-threaded machines. */
738	lis	r3,0x8000
739	rldicr	r3,r3,32,15		/* r3 = (r3 << 32) & 0xffff000000000000 */
740	addi	r3,r3,18		/* r3 = 0x8000000000000012 which is "yield" */
741	li	r4,0			/* "yield timed" */
742	li	r5,-1			/* "yield forever" */
743#endif /* CONFIG_SMP */
744	li	r0,-1			/* r0=-1 indicates a Hypervisor call */
745	sc				/* Invoke the hypervisor via a system call */
746	mfspr	r13,SPRN_SPRG3		/* Put r13 back ???? */
747	b	1b			/* If SMP not configured, secondaries
748					 * loop forever */
749
750	.globl decrementer_iSeries_masked
751decrementer_iSeries_masked:
752	/* We may not have a valid TOC pointer in here. */
753	li	r11,1
754	ld	r12,PACALPPACAPTR(r13)
755	stb	r11,LPPACADECRINT(r12)
756	LOAD_REG_IMMEDIATE(r12, tb_ticks_per_jiffy)
757	lwz	r12,0(r12)
758	mtspr	SPRN_DEC,r12
759	/* fall through */
760
761	.globl hardware_interrupt_iSeries_masked
762hardware_interrupt_iSeries_masked:
763	mtcrf	0x80,r9		/* Restore regs */
764	ld	r12,PACALPPACAPTR(r13)
765	ld	r11,LPPACASRR0(r12)
766	ld	r12,LPPACASRR1(r12)
767	mtspr	SPRN_SRR0,r11
768	mtspr	SPRN_SRR1,r12
769	ld	r9,PACA_EXGEN+EX_R9(r13)
770	ld	r10,PACA_EXGEN+EX_R10(r13)
771	ld	r11,PACA_EXGEN+EX_R11(r13)
772	ld	r12,PACA_EXGEN+EX_R12(r13)
773	ld	r13,PACA_EXGEN+EX_R13(r13)
774	rfid
775	b	.	/* prevent speculative execution */
776#endif /* CONFIG_PPC_ISERIES */
777
778/*** Common interrupt handlers ***/
779
780	STD_EXCEPTION_COMMON(0x100, system_reset, .system_reset_exception)
781
782	/*
783	 * Machine check is different because we use a different
784	 * save area: PACA_EXMC instead of PACA_EXGEN.
785	 */
786	.align	7
787	.globl machine_check_common
788machine_check_common:
789	EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
790	DISABLE_INTS
791	bl	.save_nvgprs
792	addi	r3,r1,STACK_FRAME_OVERHEAD
793	bl	.machine_check_exception
794	b	.ret_from_except
795
796	STD_EXCEPTION_COMMON_LITE(0x900, decrementer, .timer_interrupt)
797	STD_EXCEPTION_COMMON(0xa00, trap_0a, .unknown_exception)
798	STD_EXCEPTION_COMMON(0xb00, trap_0b, .unknown_exception)
799	STD_EXCEPTION_COMMON(0xd00, single_step, .single_step_exception)
800	STD_EXCEPTION_COMMON(0xe00, trap_0e, .unknown_exception)
801	STD_EXCEPTION_COMMON(0xf00, performance_monitor, .performance_monitor_exception)
802	STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, .instruction_breakpoint_exception)
803#ifdef CONFIG_ALTIVEC
804	STD_EXCEPTION_COMMON(0x1700, altivec_assist, .altivec_assist_exception)
805#else
806	STD_EXCEPTION_COMMON(0x1700, altivec_assist, .unknown_exception)
807#endif
808
809/*
810 * Here we have detected that the kernel stack pointer is bad.
811 * R9 contains the saved CR, r13 points to the paca,
812 * r10 contains the (bad) kernel stack pointer,
813 * r11 and r12 contain the saved SRR0 and SRR1.
814 * We switch to using an emergency stack, save the registers there,
815 * and call kernel_bad_stack(), which panics.
816 */
817bad_stack:
818	ld	r1,PACAEMERGSP(r13)
819	subi	r1,r1,64+INT_FRAME_SIZE
820	std	r9,_CCR(r1)
821	std	r10,GPR1(r1)
822	std	r11,_NIP(r1)
823	std	r12,_MSR(r1)
824	mfspr	r11,SPRN_DAR
825	mfspr	r12,SPRN_DSISR
826	std	r11,_DAR(r1)
827	std	r12,_DSISR(r1)
828	mflr	r10
829	mfctr	r11
830	mfxer	r12
831	std	r10,_LINK(r1)
832	std	r11,_CTR(r1)
833	std	r12,_XER(r1)
834	SAVE_GPR(0,r1)
835	SAVE_GPR(2,r1)
836	SAVE_4GPRS(3,r1)
837	SAVE_2GPRS(7,r1)
838	SAVE_10GPRS(12,r1)
839	SAVE_10GPRS(22,r1)
840	addi	r11,r1,INT_FRAME_SIZE
841	std	r11,0(r1)
842	li	r12,0
843	std	r12,0(r11)
844	ld	r2,PACATOC(r13)
8451:	addi	r3,r1,STACK_FRAME_OVERHEAD
846	bl	.kernel_bad_stack
847	b	1b
848
849/*
850 * Return from an exception with minimal checks.
851 * The caller is assumed to have done EXCEPTION_PROLOG_COMMON.
852 * If interrupts have been enabled, or anything has been
853 * done that might have changed the scheduling status of
854 * any task or sent any task a signal, you should use
855 * ret_from_except or ret_from_except_lite instead of this.
856 */
857	.globl	fast_exception_return
858fast_exception_return:
859	ld	r12,_MSR(r1)
860	ld	r11,_NIP(r1)
861	andi.	r3,r12,MSR_RI		/* check if RI is set */
862	beq-	unrecov_fer
863	ld	r3,_CCR(r1)
864	ld	r4,_LINK(r1)
865	ld	r5,_CTR(r1)
866	ld	r6,_XER(r1)
867	mtcr	r3
868	mtlr	r4
869	mtctr	r5
870	mtxer	r6
871	REST_GPR(0, r1)
872	REST_8GPRS(2, r1)
873
874	mfmsr	r10
875	clrrdi	r10,r10,2		/* clear RI (LE is 0 already) */
876	mtmsrd	r10,1
877
878	mtspr	SPRN_SRR1,r12
879	mtspr	SPRN_SRR0,r11
880	REST_4GPRS(10, r1)
881	ld	r1,GPR1(r1)
882	rfid
883	b	.	/* prevent speculative execution */
884
885unrecov_fer:
886	bl	.save_nvgprs
8871:	addi	r3,r1,STACK_FRAME_OVERHEAD
888	bl	.unrecoverable_exception
889	b	1b
890
891/*
892 * Here r13 points to the paca, r9 contains the saved CR,
893 * SRR0 and SRR1 are saved in r11 and r12,
894 * r9 - r13 are saved in paca->exgen.
895 */
896	.align	7
897	.globl data_access_common
898data_access_common:
899	RUNLATCH_ON(r10)		/* It wont fit in the 0x300 handler */
900	mfspr	r10,SPRN_DAR
901	std	r10,PACA_EXGEN+EX_DAR(r13)
902	mfspr	r10,SPRN_DSISR
903	stw	r10,PACA_EXGEN+EX_DSISR(r13)
904	EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
905	ld	r3,PACA_EXGEN+EX_DAR(r13)
906	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
907	li	r5,0x300
908	b	.do_hash_page	 	/* Try to handle as hpte fault */
909
910	.align	7
911	.globl instruction_access_common
912instruction_access_common:
913	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
914	ld	r3,_NIP(r1)
915	andis.	r4,r12,0x5820
916	li	r5,0x400
917	b	.do_hash_page		/* Try to handle as hpte fault */
918
919/*
920 * Here is the common SLB miss user that is used when going to virtual
921 * mode for SLB misses, that is currently not used
922 */
923#ifdef __DISABLED__
924	.align	7
925	.globl	slb_miss_user_common
926slb_miss_user_common:
927	mflr	r10
928	std	r3,PACA_EXGEN+EX_DAR(r13)
929	stw	r9,PACA_EXGEN+EX_CCR(r13)
930	std	r10,PACA_EXGEN+EX_LR(r13)
931	std	r11,PACA_EXGEN+EX_SRR0(r13)
932	bl	.slb_allocate_user
933
934	ld	r10,PACA_EXGEN+EX_LR(r13)
935	ld	r3,PACA_EXGEN+EX_R3(r13)
936	lwz	r9,PACA_EXGEN+EX_CCR(r13)
937	ld	r11,PACA_EXGEN+EX_SRR0(r13)
938	mtlr	r10
939	beq-	slb_miss_fault
940
941	andi.	r10,r12,MSR_RI		/* check for unrecoverable exception */
942	beq-	unrecov_user_slb
943	mfmsr	r10
944
945.machine push
946.machine "power4"
947	mtcrf	0x80,r9
948.machine pop
949
950	clrrdi	r10,r10,2		/* clear RI before setting SRR0/1 */
951	mtmsrd	r10,1
952
953	mtspr	SRR0,r11
954	mtspr	SRR1,r12
955
956	ld	r9,PACA_EXGEN+EX_R9(r13)
957	ld	r10,PACA_EXGEN+EX_R10(r13)
958	ld	r11,PACA_EXGEN+EX_R11(r13)
959	ld	r12,PACA_EXGEN+EX_R12(r13)
960	ld	r13,PACA_EXGEN+EX_R13(r13)
961	rfid
962	b	.
963
964slb_miss_fault:
965	EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN)
966	ld	r4,PACA_EXGEN+EX_DAR(r13)
967	li	r5,0
968	std	r4,_DAR(r1)
969	std	r5,_DSISR(r1)
970	b	.handle_page_fault
971
972unrecov_user_slb:
973	EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN)
974	DISABLE_INTS
975	bl	.save_nvgprs
9761:	addi	r3,r1,STACK_FRAME_OVERHEAD
977	bl	.unrecoverable_exception
978	b	1b
979
980#endif /* __DISABLED__ */
981
982
983/*
984 * r13 points to the PACA, r9 contains the saved CR,
985 * r12 contain the saved SRR1, SRR0 is still ready for return
986 * r3 has the faulting address
987 * r9 - r13 are saved in paca->exslb.
988 * r3 is saved in paca->slb_r3
989 * We assume we aren't going to take any exceptions during this procedure.
990 */
991_GLOBAL(slb_miss_realmode)
992	mflr	r10
993
994	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
995	std	r10,PACA_EXSLB+EX_LR(r13)	/* save LR */
996
997	bl	.slb_allocate_realmode
998
999	/* All done -- return from exception. */
1000
1001	ld	r10,PACA_EXSLB+EX_LR(r13)
1002	ld	r3,PACA_EXSLB+EX_R3(r13)
1003	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
1004#ifdef CONFIG_PPC_ISERIES
1005	ld	r11,PACALPPACAPTR(r13)
1006	ld	r11,LPPACASRR0(r11)		/* get SRR0 value */
1007#endif /* CONFIG_PPC_ISERIES */
1008
1009	mtlr	r10
1010
1011	andi.	r10,r12,MSR_RI	/* check for unrecoverable exception */
1012	beq-	unrecov_slb
1013
1014.machine	push
1015.machine	"power4"
1016	mtcrf	0x80,r9
1017	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */
1018.machine	pop
1019
1020#ifdef CONFIG_PPC_ISERIES
1021	mtspr	SPRN_SRR0,r11
1022	mtspr	SPRN_SRR1,r12
1023#endif /* CONFIG_PPC_ISERIES */
1024	ld	r9,PACA_EXSLB+EX_R9(r13)
1025	ld	r10,PACA_EXSLB+EX_R10(r13)
1026	ld	r11,PACA_EXSLB+EX_R11(r13)
1027	ld	r12,PACA_EXSLB+EX_R12(r13)
1028	ld	r13,PACA_EXSLB+EX_R13(r13)
1029	rfid
1030	b	.	/* prevent speculative execution */
1031
1032unrecov_slb:
1033	EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
1034	DISABLE_INTS
1035	bl	.save_nvgprs
10361:	addi	r3,r1,STACK_FRAME_OVERHEAD
1037	bl	.unrecoverable_exception
1038	b	1b
1039
1040	.align	7
1041	.globl hardware_interrupt_common
1042	.globl hardware_interrupt_entry
1043hardware_interrupt_common:
1044	EXCEPTION_PROLOG_COMMON(0x500, PACA_EXGEN)
1045hardware_interrupt_entry:
1046	DISABLE_INTS
1047	addi	r3,r1,STACK_FRAME_OVERHEAD
1048	bl	.do_IRQ
1049	b	.ret_from_except_lite
1050
1051	.align	7
1052	.globl alignment_common
1053alignment_common:
1054	mfspr	r10,SPRN_DAR
1055	std	r10,PACA_EXGEN+EX_DAR(r13)
1056	mfspr	r10,SPRN_DSISR
1057	stw	r10,PACA_EXGEN+EX_DSISR(r13)
1058	EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
1059	ld	r3,PACA_EXGEN+EX_DAR(r13)
1060	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
1061	std	r3,_DAR(r1)
1062	std	r4,_DSISR(r1)
1063	bl	.save_nvgprs
1064	addi	r3,r1,STACK_FRAME_OVERHEAD
1065	ENABLE_INTS
1066	bl	.alignment_exception
1067	b	.ret_from_except
1068
1069	.align	7
1070	.globl program_check_common
1071program_check_common:
1072	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
1073	bl	.save_nvgprs
1074	addi	r3,r1,STACK_FRAME_OVERHEAD
1075	ENABLE_INTS
1076	bl	.program_check_exception
1077	b	.ret_from_except
1078
1079	.align	7
1080	.globl fp_unavailable_common
1081fp_unavailable_common:
1082	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
1083	bne	.load_up_fpu		/* if from user, just load it up */
1084	bl	.save_nvgprs
1085	addi	r3,r1,STACK_FRAME_OVERHEAD
1086	ENABLE_INTS
1087	bl	.kernel_fp_unavailable_exception
1088	BUG_OPCODE
1089
1090	.align	7
1091	.globl altivec_unavailable_common
1092altivec_unavailable_common:
1093	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
1094#ifdef CONFIG_ALTIVEC
1095BEGIN_FTR_SECTION
1096	bne	.load_up_altivec	/* if from user, just load it up */
1097END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
1098#endif
1099	bl	.save_nvgprs
1100	addi	r3,r1,STACK_FRAME_OVERHEAD
1101	ENABLE_INTS
1102	bl	.altivec_unavailable_exception
1103	b	.ret_from_except
1104
1105#ifdef CONFIG_ALTIVEC
1106/*
1107 * load_up_altivec(unused, unused, tsk)
1108 * Disable VMX for the task which had it previously,
1109 * and save its vector registers in its thread_struct.
1110 * Enables the VMX for use in the kernel on return.
1111 * On SMP we know the VMX is free, since we give it up every
1112 * switch (ie, no lazy save of the vector registers).
1113 * On entry: r13 == 'current' && last_task_used_altivec != 'current'
1114 */
1115_STATIC(load_up_altivec)
1116	mfmsr	r5			/* grab the current MSR */
1117	oris	r5,r5,MSR_VEC@h
1118	mtmsrd	r5			/* enable use of VMX now */
1119	isync
1120
1121/*
1122 * For SMP, we don't do lazy VMX switching because it just gets too
1123 * horrendously complex, especially when a task switches from one CPU
1124 * to another.  Instead we call giveup_altvec in switch_to.
1125 * VRSAVE isn't dealt with here, that is done in the normal context
1126 * switch code. Note that we could rely on vrsave value to eventually
1127 * avoid saving all of the VREGs here...
1128 */
1129#ifndef CONFIG_SMP
1130	ld	r3,last_task_used_altivec@got(r2)
1131	ld	r4,0(r3)
1132	cmpdi	0,r4,0
1133	beq	1f
1134	/* Save VMX state to last_task_used_altivec's THREAD struct */
1135	addi	r4,r4,THREAD
1136	SAVE_32VRS(0,r5,r4)
1137	mfvscr	vr0
1138	li	r10,THREAD_VSCR
1139	stvx	vr0,r10,r4
1140	/* Disable VMX for last_task_used_altivec */
1141	ld	r5,PT_REGS(r4)
1142	ld	r4,_MSR-STACK_FRAME_OVERHEAD(r5)
1143	lis	r6,MSR_VEC@h
1144	andc	r4,r4,r6
1145	std	r4,_MSR-STACK_FRAME_OVERHEAD(r5)
11461:
1147#endif /* CONFIG_SMP */
1148	/* Hack: if we get an altivec unavailable trap with VRSAVE
1149	 * set to all zeros, we assume this is a broken application
1150	 * that fails to set it properly, and thus we switch it to
1151	 * all 1's
1152	 */
1153	mfspr	r4,SPRN_VRSAVE
1154	cmpdi	0,r4,0
1155	bne+	1f
1156	li	r4,-1
1157	mtspr	SPRN_VRSAVE,r4
11581:
1159	/* enable use of VMX after return */
1160	ld	r4,PACACURRENT(r13)
1161	addi	r5,r4,THREAD		/* Get THREAD */
1162	oris	r12,r12,MSR_VEC@h
1163	std	r12,_MSR(r1)
1164	li	r4,1
1165	li	r10,THREAD_VSCR
1166	stw	r4,THREAD_USED_VR(r5)
1167	lvx	vr0,r10,r5
1168	mtvscr	vr0
1169	REST_32VRS(0,r4,r5)
1170#ifndef CONFIG_SMP
1171	/* Update last_task_used_math to 'current' */
1172	subi	r4,r5,THREAD		/* Back to 'current' */
1173	std	r4,0(r3)
1174#endif /* CONFIG_SMP */
1175	/* restore registers and return */
1176	b	fast_exception_return
1177#endif /* CONFIG_ALTIVEC */
1178
1179/*
1180 * Hash table stuff
1181 */
1182	.align	7
1183_GLOBAL(do_hash_page)
1184	std	r3,_DAR(r1)
1185	std	r4,_DSISR(r1)
1186
1187	andis.	r0,r4,0xa450		/* weird error? */
1188	bne-	.handle_page_fault	/* if not, try to insert a HPTE */
1189BEGIN_FTR_SECTION
1190	andis.	r0,r4,0x0020		/* Is it a segment table fault? */
1191	bne-	.do_ste_alloc		/* If so handle it */
1192END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
1193
1194	/*
1195	 * We need to set the _PAGE_USER bit if MSR_PR is set or if we are
1196	 * accessing a userspace segment (even from the kernel). We assume
1197	 * kernel addresses always have the high bit set.
1198	 */
1199	rlwinm	r4,r4,32-25+9,31-9,31-9	/* DSISR_STORE -> _PAGE_RW */
1200	rotldi	r0,r3,15		/* Move high bit into MSR_PR posn */
1201	orc	r0,r12,r0		/* MSR_PR | ~high_bit */
1202	rlwimi	r4,r0,32-13,30,30	/* becomes _PAGE_USER access bit */
1203	ori	r4,r4,1			/* add _PAGE_PRESENT */
1204	rlwimi	r4,r5,22+2,31-2,31-2	/* Set _PAGE_EXEC if trap is 0x400 */
1205
1206	/*
1207	 * On iSeries, we soft-disable interrupts here, then
1208	 * hard-enable interrupts so that the hash_page code can spin on
1209	 * the hash_table_lock without problems on a shared processor.
1210	 */
1211	DISABLE_INTS
1212
1213	/*
1214	 * r3 contains the faulting address
1215	 * r4 contains the required access permissions
1216	 * r5 contains the trap number
1217	 *
1218	 * at return r3 = 0 for success
1219	 */
1220	bl	.hash_page		/* build HPTE if possible */
1221	cmpdi	r3,0			/* see if hash_page succeeded */
1222
1223#ifdef DO_SOFT_DISABLE
1224	/*
1225	 * If we had interrupts soft-enabled at the point where the
1226	 * DSI/ISI occurred, and an interrupt came in during hash_page,
1227	 * handle it now.
1228	 * We jump to ret_from_except_lite rather than fast_exception_return
1229	 * because ret_from_except_lite will check for and handle pending
1230	 * interrupts if necessary.
1231	 */
1232	beq	.ret_from_except_lite
1233	/* For a hash failure, we don't bother re-enabling interrupts */
1234	ble-	12f
1235
1236	/*
1237	 * hash_page couldn't handle it, set soft interrupt enable back
1238	 * to what it was before the trap.  Note that .local_irq_restore
1239	 * handles any interrupts pending at this point.
1240	 */
1241	ld	r3,SOFTE(r1)
1242	bl	.local_irq_restore
1243	b	11f
1244#else
1245	beq	fast_exception_return   /* Return from exception on success */
1246	ble-	12f			/* Failure return from hash_page */
1247
1248	/* fall through */
1249#endif
1250
1251/* Here we have a page fault that hash_page can't handle. */
1252_GLOBAL(handle_page_fault)
1253	ENABLE_INTS
125411:	ld	r4,_DAR(r1)
1255	ld	r5,_DSISR(r1)
1256	addi	r3,r1,STACK_FRAME_OVERHEAD
1257	bl	.do_page_fault
1258	cmpdi	r3,0
1259	beq+	.ret_from_except_lite
1260	bl	.save_nvgprs
1261	mr	r5,r3
1262	addi	r3,r1,STACK_FRAME_OVERHEAD
1263	lwz	r4,_DAR(r1)
1264	bl	.bad_page_fault
1265	b	.ret_from_except
1266
1267/* We have a page fault that hash_page could handle but HV refused
1268 * the PTE insertion
1269 */
127012:	bl	.save_nvgprs
1271	addi	r3,r1,STACK_FRAME_OVERHEAD
1272	lwz	r4,_DAR(r1)
1273	bl	.low_hash_fault
1274	b	.ret_from_except
1275
1276	/* here we have a segment miss */
1277_GLOBAL(do_ste_alloc)
1278	bl	.ste_allocate		/* try to insert stab entry */
1279	cmpdi	r3,0
1280	beq+	fast_exception_return
1281	b	.handle_page_fault
1282
1283/*
1284 * r13 points to the PACA, r9 contains the saved CR,
1285 * r11 and r12 contain the saved SRR0 and SRR1.
1286 * r9 - r13 are saved in paca->exslb.
1287 * We assume we aren't going to take any exceptions during this procedure.
1288 * We assume (DAR >> 60) == 0xc.
1289 */
1290	.align	7
1291_GLOBAL(do_stab_bolted)
1292	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
1293	std	r11,PACA_EXSLB+EX_SRR0(r13)	/* save SRR0 in exc. frame */
1294
1295	/* Hash to the primary group */
1296	ld	r10,PACASTABVIRT(r13)
1297	mfspr	r11,SPRN_DAR
1298	srdi	r11,r11,28
1299	rldimi	r10,r11,7,52	/* r10 = first ste of the group */
1300
1301	/* Calculate VSID */
1302	/* This is a kernel address, so protovsid = ESID */
1303	ASM_VSID_SCRAMBLE(r11, r9)
1304	rldic	r9,r11,12,16	/* r9 = vsid << 12 */
1305
1306	/* Search the primary group for a free entry */
13071:	ld	r11,0(r10)	/* Test valid bit of the current ste	*/
1308	andi.	r11,r11,0x80
1309	beq	2f
1310	addi	r10,r10,16
1311	andi.	r11,r10,0x70
1312	bne	1b
1313
1314	/* Stick for only searching the primary group for now.		*/
1315	/* At least for now, we use a very simple random castout scheme */
1316	/* Use the TB as a random number ;  OR in 1 to avoid entry 0	*/
1317	mftb	r11
1318	rldic	r11,r11,4,57	/* r11 = (r11 << 4) & 0x70 */
1319	ori	r11,r11,0x10
1320
1321	/* r10 currently points to an ste one past the group of interest */
1322	/* make it point to the randomly selected entry			*/
1323	subi	r10,r10,128
1324	or 	r10,r10,r11	/* r10 is the entry to invalidate	*/
1325
1326	isync			/* mark the entry invalid		*/
1327	ld	r11,0(r10)
1328	rldicl	r11,r11,56,1	/* clear the valid bit */
1329	rotldi	r11,r11,8
1330	std	r11,0(r10)
1331	sync
1332
1333	clrrdi	r11,r11,28	/* Get the esid part of the ste		*/
1334	slbie	r11
1335
13362:	std	r9,8(r10)	/* Store the vsid part of the ste	*/
1337	eieio
1338
1339	mfspr	r11,SPRN_DAR		/* Get the new esid			*/
1340	clrrdi	r11,r11,28	/* Permits a full 32b of ESID		*/
1341	ori	r11,r11,0x90	/* Turn on valid and kp			*/
1342	std	r11,0(r10)	/* Put new entry back into the stab	*/
1343
1344	sync
1345
1346	/* All done -- return from exception. */
1347	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
1348	ld	r11,PACA_EXSLB+EX_SRR0(r13)	/* get saved SRR0 */
1349
1350	andi.	r10,r12,MSR_RI
1351	beq-	unrecov_slb
1352
1353	mtcrf	0x80,r9			/* restore CR */
1354
1355	mfmsr	r10
1356	clrrdi	r10,r10,2
1357	mtmsrd	r10,1
1358
1359	mtspr	SPRN_SRR0,r11
1360	mtspr	SPRN_SRR1,r12
1361	ld	r9,PACA_EXSLB+EX_R9(r13)
1362	ld	r10,PACA_EXSLB+EX_R10(r13)
1363	ld	r11,PACA_EXSLB+EX_R11(r13)
1364	ld	r12,PACA_EXSLB+EX_R12(r13)
1365	ld	r13,PACA_EXSLB+EX_R13(r13)
1366	rfid
1367	b	.	/* prevent speculative execution */
1368
1369/*
1370 * Space for CPU0's segment table.
1371 *
1372 * On iSeries, the hypervisor must fill in at least one entry before
1373 * we get control (with relocate on).  The address is give to the hv
1374 * as a page number (see xLparMap in lpardata.c), so this must be at a
1375 * fixed address (the linker can't compute (u64)&initial_stab >>
1376 * PAGE_SHIFT).
1377 */
1378	. = STAB0_OFFSET	/* 0x6000 */
1379	.globl initial_stab
1380initial_stab:
1381	.space	4096
1382
1383/*
1384 * Data area reserved for FWNMI option.
1385 * This address (0x7000) is fixed by the RPA.
1386 */
1387	.= 0x7000
1388	.globl fwnmi_data_area
1389fwnmi_data_area:
1390
1391	/* iSeries does not use the FWNMI stuff, so it is safe to put
1392	 * this here, even if we later allow kernels that will boot on
1393	 * both pSeries and iSeries */
1394#ifdef CONFIG_PPC_ISERIES
1395        . = LPARMAP_PHYS
1396#include "lparmap.s"
1397/*
1398 * This ".text" is here for old compilers that generate a trailing
1399 * .note section when compiling .c files to .s
1400 */
1401	.text
1402#endif /* CONFIG_PPC_ISERIES */
1403
1404        . = 0x8000
1405
1406/*
1407 * On pSeries, secondary processors spin in the following code.
1408 * At entry, r3 = this processor's number (physical cpu id)
1409 */
1410_GLOBAL(pSeries_secondary_smp_init)
1411	mr	r24,r3
1412
1413	/* turn on 64-bit mode */
1414	bl	.enable_64b_mode
1415	isync
1416
1417	/* Copy some CPU settings from CPU 0 */
1418	bl	.__restore_cpu_setup
1419
1420	/* Set up a paca value for this processor. Since we have the
1421	 * physical cpu id in r24, we need to search the pacas to find
1422	 * which logical id maps to our physical one.
1423	 */
1424	LOAD_REG_IMMEDIATE(r13, paca)	/* Get base vaddr of paca array	 */
1425	li	r5,0			/* logical cpu id                */
14261:	lhz	r6,PACAHWCPUID(r13)	/* Load HW procid from paca      */
1427	cmpw	r6,r24			/* Compare to our id             */
1428	beq	2f
1429	addi	r13,r13,PACA_SIZE	/* Loop to next PACA on miss     */
1430	addi	r5,r5,1
1431	cmpwi	r5,NR_CPUS
1432	blt	1b
1433
1434	mr	r3,r24			/* not found, copy phys to r3	 */
1435	b	.kexec_wait		/* next kernel might do better	 */
1436
14372:	mtspr	SPRN_SPRG3,r13		/* Save vaddr of paca in SPRG3	 */
1438	/* From now on, r24 is expected to be logical cpuid */
1439	mr	r24,r5
14403:	HMT_LOW
1441	lbz	r23,PACAPROCSTART(r13)	/* Test if this processor should */
1442					/* start.			 */
1443	sync
1444
1445	/* Create a temp kernel stack for use before relocation is on.	*/
1446	ld	r1,PACAEMERGSP(r13)
1447	subi	r1,r1,STACK_FRAME_OVERHEAD
1448
1449	cmpwi	0,r23,0
1450#ifdef CONFIG_SMP
1451	bne	.__secondary_start
1452#endif
1453	b 	3b			/* Loop until told to go	 */
1454
1455#ifdef CONFIG_PPC_ISERIES
1456_STATIC(__start_initialization_iSeries)
1457	/* Clear out the BSS */
1458	LOAD_REG_IMMEDIATE(r11,__bss_stop)
1459	LOAD_REG_IMMEDIATE(r8,__bss_start)
1460	sub	r11,r11,r8		/* bss size			*/
1461	addi	r11,r11,7		/* round up to an even double word */
1462	rldicl. r11,r11,61,3		/* shift right by 3		*/
1463	beq	4f
1464	addi	r8,r8,-8
1465	li	r0,0
1466	mtctr	r11			/* zero this many doublewords	*/
14673:	stdu	r0,8(r8)
1468	bdnz	3b
14694:
1470	LOAD_REG_IMMEDIATE(r1,init_thread_union)
1471	addi	r1,r1,THREAD_SIZE
1472	li	r0,0
1473	stdu	r0,-STACK_FRAME_OVERHEAD(r1)
1474
1475	LOAD_REG_IMMEDIATE(r3,cpu_specs)
1476	LOAD_REG_IMMEDIATE(r4,cur_cpu_spec)
1477	li	r5,0
1478	bl	.identify_cpu
1479
1480	LOAD_REG_IMMEDIATE(r2,__toc_start)
1481	addi	r2,r2,0x4000
1482	addi	r2,r2,0x4000
1483
1484	bl	.iSeries_early_setup
1485	bl	.early_setup
1486
1487	/* relocation is on at this point */
1488
1489	b	.start_here_common
1490#endif /* CONFIG_PPC_ISERIES */
1491
1492#ifdef CONFIG_PPC_MULTIPLATFORM
1493
1494_STATIC(__mmu_off)
1495	mfmsr	r3
1496	andi.	r0,r3,MSR_IR|MSR_DR
1497	beqlr
1498	andc	r3,r3,r0
1499	mtspr	SPRN_SRR0,r4
1500	mtspr	SPRN_SRR1,r3
1501	sync
1502	rfid
1503	b	.	/* prevent speculative execution */
1504
1505
1506/*
1507 * Here is our main kernel entry point. We support currently 2 kind of entries
1508 * depending on the value of r5.
1509 *
1510 *   r5 != NULL -> OF entry, we go to prom_init, "legacy" parameter content
1511 *                 in r3...r7
1512 *
1513 *   r5 == NULL -> kexec style entry. r3 is a physical pointer to the
1514 *                 DT block, r4 is a physical pointer to the kernel itself
1515 *
1516 */
1517_GLOBAL(__start_initialization_multiplatform)
1518#ifdef CONFIG_PPC_MULTIPLATFORM
1519	/*
1520	 * Are we booted from a PROM Of-type client-interface ?
1521	 */
1522	cmpldi	cr0,r5,0
1523	bne	.__boot_from_prom		/* yes -> prom */
1524#endif
1525
1526	/* Save parameters */
1527	mr	r31,r3
1528	mr	r30,r4
1529
1530	/* Make sure we are running in 64 bits mode */
1531	bl	.enable_64b_mode
1532
1533	/* Setup some critical 970 SPRs before switching MMU off */
1534	bl	.__970_cpu_preinit
1535
1536	/* cpu # */
1537	li	r24,0
1538
1539	/* Switch off MMU if not already */
1540	LOAD_REG_IMMEDIATE(r4, .__after_prom_start - KERNELBASE)
1541	add	r4,r4,r30
1542	bl	.__mmu_off
1543	b	.__after_prom_start
1544
1545#ifdef CONFIG_PPC_MULTIPLATFORM
1546_STATIC(__boot_from_prom)
1547	/* Save parameters */
1548	mr	r31,r3
1549	mr	r30,r4
1550	mr	r29,r5
1551	mr	r28,r6
1552	mr	r27,r7
1553
1554	/* Make sure we are running in 64 bits mode */
1555	bl	.enable_64b_mode
1556
1557	/* put a relocation offset into r3 */
1558	bl	.reloc_offset
1559
1560	LOAD_REG_IMMEDIATE(r2,__toc_start)
1561	addi	r2,r2,0x4000
1562	addi	r2,r2,0x4000
1563
1564	/* Relocate the TOC from a virt addr to a real addr */
1565	add	r2,r2,r3
1566
1567	/* Restore parameters */
1568	mr	r3,r31
1569	mr	r4,r30
1570	mr	r5,r29
1571	mr	r6,r28
1572	mr	r7,r27
1573
1574	/* Do all of the interaction with OF client interface */
1575	bl	.prom_init
1576	/* We never return */
1577	trap
1578#endif
1579
1580/*
1581 * At this point, r3 contains the physical address we are running at,
1582 * returned by prom_init()
1583 */
1584_STATIC(__after_prom_start)
1585
1586/*
1587 * We need to run with __start at physical address PHYSICAL_START.
1588 * This will leave some code in the first 256B of
1589 * real memory, which are reserved for software use.
1590 * The remainder of the first page is loaded with the fixed
1591 * interrupt vectors.  The next two pages are filled with
1592 * unknown exception placeholders.
1593 *
1594 * Note: This process overwrites the OF exception vectors.
1595 *	r26 == relocation offset
1596 *	r27 == KERNELBASE
1597 */
1598	bl	.reloc_offset
1599	mr	r26,r3
1600	LOAD_REG_IMMEDIATE(r27, KERNELBASE)
1601
1602	LOAD_REG_IMMEDIATE(r3, PHYSICAL_START)	/* target addr */
1603
1604	// XXX FIXME: Use phys returned by OF (r30)
1605	add	r4,r27,r26 		/* source addr			 */
1606					/* current address of _start	 */
1607					/*   i.e. where we are running	 */
1608					/*	the source addr		 */
1609
1610	LOAD_REG_IMMEDIATE(r5,copy_to_here) /* # bytes of memory to copy */
1611	sub	r5,r5,r27
1612
1613	li	r6,0x100		/* Start offset, the first 0x100 */
1614					/* bytes were copied earlier.	 */
1615
1616	bl	.copy_and_flush		/* copy the first n bytes	 */
1617					/* this includes the code being	 */
1618					/* executed here.		 */
1619
1620	LOAD_REG_IMMEDIATE(r0, 4f)	/* Jump to the copy of this code */
1621	mtctr	r0			/* that we just made/relocated	 */
1622	bctr
1623
16244:	LOAD_REG_IMMEDIATE(r5,klimit)
1625	add	r5,r5,r26
1626	ld	r5,0(r5)		/* get the value of klimit */
1627	sub	r5,r5,r27
1628	bl	.copy_and_flush		/* copy the rest */
1629	b	.start_here_multiplatform
1630
1631#endif /* CONFIG_PPC_MULTIPLATFORM */
1632
1633/*
1634 * Copy routine used to copy the kernel to start at physical address 0
1635 * and flush and invalidate the caches as needed.
1636 * r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset
1637 * on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5.
1638 *
1639 * Note: this routine *only* clobbers r0, r6 and lr
1640 */
1641_GLOBAL(copy_and_flush)
1642	addi	r5,r5,-8
1643	addi	r6,r6,-8
16444:	li	r0,16			/* Use the least common		*/
1645					/* denominator cache line	*/
1646					/* size.  This results in	*/
1647					/* extra cache line flushes	*/
1648					/* but operation is correct.	*/
1649					/* Can't get cache line size	*/
1650					/* from NACA as it is being	*/
1651					/* moved too.			*/
1652
1653	mtctr	r0			/* put # words/line in ctr	*/
16543:	addi	r6,r6,8			/* copy a cache line		*/
1655	ldx	r0,r6,r4
1656	stdx	r0,r6,r3
1657	bdnz	3b
1658	dcbst	r6,r3			/* write it to memory		*/
1659	sync
1660	icbi	r6,r3			/* flush the icache line	*/
1661	cmpld	0,r6,r5
1662	blt	4b
1663	sync
1664	addi	r5,r5,8
1665	addi	r6,r6,8
1666	blr
1667
1668.align 8
1669copy_to_here:
1670
1671#ifdef CONFIG_SMP
1672#ifdef CONFIG_PPC_PMAC
1673/*
1674 * On PowerMac, secondary processors starts from the reset vector, which
1675 * is temporarily turned into a call to one of the functions below.
1676 */
1677	.section ".text";
1678	.align 2 ;
1679
1680	.globl	__secondary_start_pmac_0
1681__secondary_start_pmac_0:
1682	/* NB the entries for cpus 0, 1, 2 must each occupy 8 bytes. */
1683	li	r24,0
1684	b	1f
1685	li	r24,1
1686	b	1f
1687	li	r24,2
1688	b	1f
1689	li	r24,3
16901:
1691
1692_GLOBAL(pmac_secondary_start)
1693	/* turn on 64-bit mode */
1694	bl	.enable_64b_mode
1695	isync
1696
1697	/* Copy some CPU settings from CPU 0 */
1698	bl	.__restore_cpu_setup
1699
1700	/* pSeries do that early though I don't think we really need it */
1701	mfmsr	r3
1702	ori	r3,r3,MSR_RI
1703	mtmsrd	r3			/* RI on */
1704
1705	/* Set up a paca value for this processor. */
1706	LOAD_REG_IMMEDIATE(r4, paca)	/* Get base vaddr of paca array	*/
1707	mulli	r13,r24,PACA_SIZE	 /* Calculate vaddr of right paca */
1708	add	r13,r13,r4		/* for this processor.		*/
1709	mtspr	SPRN_SPRG3,r13		 /* Save vaddr of paca in SPRG3	*/
1710
1711	/* Create a temp kernel stack for use before relocation is on.	*/
1712	ld	r1,PACAEMERGSP(r13)
1713	subi	r1,r1,STACK_FRAME_OVERHEAD
1714
1715	b	.__secondary_start
1716
1717#endif /* CONFIG_PPC_PMAC */
1718
1719/*
1720 * This function is called after the master CPU has released the
1721 * secondary processors.  The execution environment is relocation off.
1722 * The paca for this processor has the following fields initialized at
1723 * this point:
1724 *   1. Processor number
1725 *   2. Segment table pointer (virtual address)
1726 * On entry the following are set:
1727 *   r1	= stack pointer.  vaddr for iSeries, raddr (temp stack) for pSeries
1728 *   r24   = cpu# (in Linux terms)
1729 *   r13   = paca virtual address
1730 *   SPRG3 = paca virtual address
1731 */
1732_GLOBAL(__secondary_start)
1733	/* Set thread priority to MEDIUM */
1734	HMT_MEDIUM
1735
1736	/* Load TOC */
1737	ld	r2,PACATOC(r13)
1738
1739	/* Do early setup for that CPU (stab, slb, hash table pointer) */
1740	bl	.early_setup_secondary
1741
1742	/* Initialize the kernel stack.  Just a repeat for iSeries.	 */
1743	LOAD_REG_ADDR(r3, current_set)
1744	sldi	r28,r24,3		/* get current_set[cpu#]	 */
1745	ldx	r1,r3,r28
1746	addi	r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
1747	std	r1,PACAKSAVE(r13)
1748
1749	/* Clear backchain so we get nice backtraces */
1750	li	r7,0
1751	mtlr	r7
1752
1753	/* enable MMU and jump to start_secondary */
1754	LOAD_REG_ADDR(r3, .start_secondary_prolog)
1755	LOAD_REG_IMMEDIATE(r4, MSR_KERNEL)
1756#ifdef DO_SOFT_DISABLE
1757	ori	r4,r4,MSR_EE
1758#endif
1759	mtspr	SPRN_SRR0,r3
1760	mtspr	SPRN_SRR1,r4
1761	rfid
1762	b	.	/* prevent speculative execution */
1763
1764/*
1765 * Running with relocation on at this point.  All we want to do is
1766 * zero the stack back-chain pointer before going into C code.
1767 */
1768_GLOBAL(start_secondary_prolog)
1769	li	r3,0
1770	std	r3,0(r1)		/* Zero the stack frame pointer	*/
1771	bl	.start_secondary
1772	b	.
1773#endif
1774
1775/*
1776 * This subroutine clobbers r11 and r12
1777 */
1778_GLOBAL(enable_64b_mode)
1779	mfmsr	r11			/* grab the current MSR */
1780	li	r12,1
1781	rldicr	r12,r12,MSR_SF_LG,(63-MSR_SF_LG)
1782	or	r11,r11,r12
1783	li	r12,1
1784	rldicr	r12,r12,MSR_ISF_LG,(63-MSR_ISF_LG)
1785	or	r11,r11,r12
1786	mtmsrd	r11
1787	isync
1788	blr
1789
1790#ifdef CONFIG_PPC_MULTIPLATFORM
1791/*
1792 * This is where the main kernel code starts.
1793 */
1794_STATIC(start_here_multiplatform)
1795	/* get a new offset, now that the kernel has moved. */
1796	bl	.reloc_offset
1797	mr	r26,r3
1798
1799	/* Clear out the BSS. It may have been done in prom_init,
1800	 * already but that's irrelevant since prom_init will soon
1801	 * be detached from the kernel completely. Besides, we need
1802	 * to clear it now for kexec-style entry.
1803	 */
1804	LOAD_REG_IMMEDIATE(r11,__bss_stop)
1805	LOAD_REG_IMMEDIATE(r8,__bss_start)
1806	sub	r11,r11,r8		/* bss size			*/
1807	addi	r11,r11,7		/* round up to an even double word */
1808	rldicl. r11,r11,61,3		/* shift right by 3		*/
1809	beq	4f
1810	addi	r8,r8,-8
1811	li	r0,0
1812	mtctr	r11			/* zero this many doublewords	*/
18133:	stdu	r0,8(r8)
1814	bdnz	3b
18154:
1816
1817	mfmsr	r6
1818	ori	r6,r6,MSR_RI
1819	mtmsrd	r6			/* RI on */
1820
1821#ifdef CONFIG_HMT
1822	/* Start up the second thread on cpu 0 */
1823	mfspr	r3,SPRN_PVR
1824	srwi	r3,r3,16
1825	cmpwi	r3,0x34			/* Pulsar  */
1826	beq	90f
1827	cmpwi	r3,0x36			/* Icestar */
1828	beq	90f
1829	cmpwi	r3,0x37			/* SStar   */
1830	beq	90f
1831	b	91f			/* HMT not supported */
183290:	li	r3,0
1833	bl	.hmt_start_secondary
183491:
1835#endif
1836
1837	/* The following gets the stack and TOC set up with the regs */
1838	/* pointing to the real addr of the kernel stack.  This is   */
1839	/* all done to support the C function call below which sets  */
1840	/* up the htab.  This is done because we have relocated the  */
1841	/* kernel but are still running in real mode. */
1842
1843	LOAD_REG_IMMEDIATE(r3,init_thread_union)
1844	add	r3,r3,r26
1845
1846	/* set up a stack pointer (physical address) */
1847	addi	r1,r3,THREAD_SIZE
1848	li	r0,0
1849	stdu	r0,-STACK_FRAME_OVERHEAD(r1)
1850
1851	/* set up the TOC (physical address) */
1852	LOAD_REG_IMMEDIATE(r2,__toc_start)
1853	addi	r2,r2,0x4000
1854	addi	r2,r2,0x4000
1855	add	r2,r2,r26
1856
1857	LOAD_REG_IMMEDIATE(r3, cpu_specs)
1858	add	r3,r3,r26
1859	LOAD_REG_IMMEDIATE(r4,cur_cpu_spec)
1860	add	r4,r4,r26
1861	mr	r5,r26
1862	bl	.identify_cpu
1863
1864	/* Save some low level config HIDs of CPU0 to be copied to
1865	 * other CPUs later on, or used for suspend/resume
1866	 */
1867	bl	.__save_cpu_setup
1868	sync
1869
1870	/* Setup a valid physical PACA pointer in SPRG3 for early_setup
1871	 * note that boot_cpuid can always be 0 nowadays since there is
1872	 * nowhere it can be initialized differently before we reach this
1873	 * code
1874	 */
1875	LOAD_REG_IMMEDIATE(r27, boot_cpuid)
1876	add	r27,r27,r26
1877	lwz	r27,0(r27)
1878
1879	LOAD_REG_IMMEDIATE(r24, paca) 	/* Get base vaddr of paca array	 */
1880	mulli	r13,r27,PACA_SIZE	/* Calculate vaddr of right paca */
1881	add	r13,r13,r24		/* for this processor.		 */
1882	add	r13,r13,r26		/* convert to physical addr	 */
1883	mtspr	SPRN_SPRG3,r13
1884
1885	/* Do very early kernel initializations, including initial hash table,
1886	 * stab and slb setup before we turn on relocation.	*/
1887
1888	/* Restore parameters passed from prom_init/kexec */
1889	mr	r3,r31
1890 	bl	.early_setup
1891
1892	LOAD_REG_IMMEDIATE(r3, .start_here_common)
1893	LOAD_REG_IMMEDIATE(r4, MSR_KERNEL)
1894	mtspr	SPRN_SRR0,r3
1895	mtspr	SPRN_SRR1,r4
1896	rfid
1897	b	.	/* prevent speculative execution */
1898#endif /* CONFIG_PPC_MULTIPLATFORM */
1899
1900	/* This is where all platforms converge execution */
1901_STATIC(start_here_common)
1902	/* relocation is on at this point */
1903
1904	/* The following code sets up the SP and TOC now that we are */
1905	/* running with translation enabled. */
1906
1907	LOAD_REG_IMMEDIATE(r3,init_thread_union)
1908
1909	/* set up the stack */
1910	addi	r1,r3,THREAD_SIZE
1911	li	r0,0
1912	stdu	r0,-STACK_FRAME_OVERHEAD(r1)
1913
1914	/* Apply the CPUs-specific fixups (nop out sections not relevant
1915	 * to this CPU
1916	 */
1917	li	r3,0
1918	bl	.do_cpu_ftr_fixups
1919
1920	LOAD_REG_IMMEDIATE(r26, boot_cpuid)
1921	lwz	r26,0(r26)
1922
1923	LOAD_REG_IMMEDIATE(r24, paca)	/* Get base vaddr of paca array  */
1924	mulli	r13,r26,PACA_SIZE	/* Calculate vaddr of right paca */
1925	add	r13,r13,r24		/* for this processor.		 */
1926	mtspr	SPRN_SPRG3,r13
1927
1928	/* ptr to current */
1929	LOAD_REG_IMMEDIATE(r4, init_task)
1930	std	r4,PACACURRENT(r13)
1931
1932	/* Load the TOC */
1933	ld	r2,PACATOC(r13)
1934	std	r1,PACAKSAVE(r13)
1935
1936	bl	.setup_system
1937
1938	/* Load up the kernel context */
19395:
1940#ifdef DO_SOFT_DISABLE
1941	li	r5,0
1942	stb	r5,PACAPROCENABLED(r13)	/* Soft Disabled */
1943	mfmsr	r5
1944	ori	r5,r5,MSR_EE		/* Hard Enabled */
1945	mtmsrd	r5
1946#endif
1947
1948	bl .start_kernel
1949
1950_GLOBAL(hmt_init)
1951#ifdef CONFIG_HMT
1952	LOAD_REG_IMMEDIATE(r5, hmt_thread_data)
1953	mfspr	r7,SPRN_PVR
1954	srwi	r7,r7,16
1955	cmpwi	r7,0x34			/* Pulsar  */
1956	beq	90f
1957	cmpwi	r7,0x36			/* Icestar */
1958	beq	91f
1959	cmpwi	r7,0x37			/* SStar   */
1960	beq	91f
1961	b	101f
196290:	mfspr	r6,SPRN_PIR
1963	andi.	r6,r6,0x1f
1964	b	92f
196591:	mfspr	r6,SPRN_PIR
1966	andi.	r6,r6,0x3ff
196792:	sldi	r4,r24,3
1968	stwx	r6,r5,r4
1969	bl	.hmt_start_secondary
1970	b	101f
1971
1972__hmt_secondary_hold:
1973	LOAD_REG_IMMEDIATE(r5, hmt_thread_data)
1974	clrldi	r5,r5,4
1975	li	r7,0
1976	mfspr	r6,SPRN_PIR
1977	mfspr	r8,SPRN_PVR
1978	srwi	r8,r8,16
1979	cmpwi	r8,0x34
1980	bne	93f
1981	andi.	r6,r6,0x1f
1982	b	103f
198393:	andi.	r6,r6,0x3f
1984
1985103:	lwzx	r8,r5,r7
1986	cmpw	r8,r6
1987	beq	104f
1988	addi	r7,r7,8
1989	b	103b
1990
1991104:	addi	r7,r7,4
1992	lwzx	r9,r5,r7
1993	mr	r24,r9
1994101:
1995#endif
1996	mr	r3,r24
1997	b	.pSeries_secondary_smp_init
1998
1999#ifdef CONFIG_HMT
2000_GLOBAL(hmt_start_secondary)
2001	LOAD_REG_IMMEDIATE(r4,__hmt_secondary_hold)
2002	clrldi	r4,r4,4
2003	mtspr	SPRN_NIADORM, r4
2004	mfspr	r4, SPRN_MSRDORM
2005	li	r5, -65
2006	and	r4, r4, r5
2007	mtspr	SPRN_MSRDORM, r4
2008	lis	r4,0xffef
2009	ori	r4,r4,0x7403
2010	mtspr	SPRN_TSC, r4
2011	li	r4,0x1f4
2012	mtspr	SPRN_TST, r4
2013	mfspr	r4, SPRN_HID0
2014	ori	r4, r4, 0x1
2015	mtspr	SPRN_HID0, r4
2016	mfspr	r4, SPRN_CTRLF
2017	oris	r4, r4, 0x40
2018	mtspr	SPRN_CTRLT, r4
2019	blr
2020#endif
2021
2022/*
2023 * We put a few things here that have to be page-aligned.
2024 * This stuff goes at the beginning of the bss, which is page-aligned.
2025 */
2026	.section ".bss"
2027
2028	.align	PAGE_SHIFT
2029
2030	.globl	empty_zero_page
2031empty_zero_page:
2032	.space	PAGE_SIZE
2033
2034	.globl	swapper_pg_dir
2035swapper_pg_dir:
2036	.space	PAGE_SIZE
2037
2038/*
2039 * This space gets a copy of optional info passed to us by the bootstrap
2040 * Used to pass parameters into the kernel like root=/dev/sda1, etc.
2041 */
2042	.globl	cmd_line
2043cmd_line:
2044	.space	COMMAND_LINE_SIZE
2045