xref: /linux/arch/powerpc/kernel/head_64.S (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
1/*
2 *  PowerPC version
3 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 *
5 *  Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
6 *    Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
7 *  Adapted for Power Macintosh by Paul Mackerras.
8 *  Low-level exception handlers and MMU support
9 *  rewritten by Paul Mackerras.
10 *    Copyright (C) 1996 Paul Mackerras.
11 *
12 *  Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
13 *    Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
14 *
15 *  This file contains the low-level support and setup for the
16 *  PowerPC-64 platform, including trap and interrupt dispatch.
17 *
18 *  This program is free software; you can redistribute it and/or
19 *  modify it under the terms of the GNU General Public License
20 *  as published by the Free Software Foundation; either version
21 *  2 of the License, or (at your option) any later version.
22 */
23
24#include <linux/config.h>
25#include <linux/threads.h>
26#include <asm/reg.h>
27#include <asm/page.h>
28#include <asm/mmu.h>
29#include <asm/ppc_asm.h>
30#include <asm/asm-offsets.h>
31#include <asm/bug.h>
32#include <asm/cputable.h>
33#include <asm/setup.h>
34#include <asm/hvcall.h>
35#include <asm/iseries/lpar_map.h>
36#include <asm/thread_info.h>
37
38#ifdef CONFIG_PPC_ISERIES
39#define DO_SOFT_DISABLE
40#endif
41
42/*
43 * We layout physical memory as follows:
44 * 0x0000 - 0x00ff : Secondary processor spin code
45 * 0x0100 - 0x2fff : pSeries Interrupt prologs
46 * 0x3000 - 0x5fff : interrupt support, iSeries and common interrupt prologs
47 * 0x6000 - 0x6fff : Initial (CPU0) segment table
48 * 0x7000 - 0x7fff : FWNMI data area
49 * 0x8000 -        : Early init and support code
50 */
51
52/*
53 *   SPRG Usage
54 *
55 *   Register	Definition
56 *
57 *   SPRG0	reserved for hypervisor
58 *   SPRG1	temp - used to save gpr
59 *   SPRG2	temp - used to save gpr
60 *   SPRG3	virt addr of paca
61 */
62
63/*
64 * Entering into this code we make the following assumptions:
65 *  For pSeries:
66 *   1. The MMU is off & open firmware is running in real mode.
67 *   2. The kernel is entered at __start
68 *
69 *  For iSeries:
70 *   1. The MMU is on (as it always is for iSeries)
71 *   2. The kernel is entered at system_reset_iSeries
72 */
73
74	.text
75	.globl  _stext
76_stext:
77#ifdef CONFIG_PPC_MULTIPLATFORM
78_GLOBAL(__start)
79	/* NOP this out unconditionally */
80BEGIN_FTR_SECTION
81	b	.__start_initialization_multiplatform
82END_FTR_SECTION(0, 1)
83#endif /* CONFIG_PPC_MULTIPLATFORM */
84
85	/* Catch branch to 0 in real mode */
86	trap
87
88#ifdef CONFIG_PPC_ISERIES
89	/*
90	 * At offset 0x20, there is a pointer to iSeries LPAR data.
91	 * This is required by the hypervisor
92	 */
93	. = 0x20
94	.llong hvReleaseData-KERNELBASE
95
96	/*
97	 * At offset 0x28 and 0x30 are offsets to the mschunks_map
98	 * array (used by the iSeries LPAR debugger to do translation
99	 * between physical addresses and absolute addresses) and
100	 * to the pidhash table (also used by the debugger)
101	 */
102	.llong mschunks_map-KERNELBASE
103	.llong 0	/* pidhash-KERNELBASE SFRXXX */
104
105	/* Offset 0x38 - Pointer to start of embedded System.map */
106	.globl	embedded_sysmap_start
107embedded_sysmap_start:
108	.llong	0
109	/* Offset 0x40 - Pointer to end of embedded System.map */
110	.globl	embedded_sysmap_end
111embedded_sysmap_end:
112	.llong	0
113
114#endif /* CONFIG_PPC_ISERIES */
115
116	/* Secondary processors spin on this value until it goes to 1. */
117	.globl  __secondary_hold_spinloop
118__secondary_hold_spinloop:
119	.llong	0x0
120
121	/* Secondary processors write this value with their cpu # */
122	/* after they enter the spin loop immediately below.	  */
123	.globl	__secondary_hold_acknowledge
124__secondary_hold_acknowledge:
125	.llong	0x0
126
127	. = 0x60
128/*
129 * The following code is used on pSeries to hold secondary processors
130 * in a spin loop after they have been freed from OpenFirmware, but
131 * before the bulk of the kernel has been relocated.  This code
132 * is relocated to physical address 0x60 before prom_init is run.
133 * All of it must fit below the first exception vector at 0x100.
134 */
135_GLOBAL(__secondary_hold)
136	mfmsr	r24
137	ori	r24,r24,MSR_RI
138	mtmsrd	r24			/* RI on */
139
140	/* Grab our physical cpu number */
141	mr	r24,r3
142
143	/* Tell the master cpu we're here */
144	/* Relocation is off & we are located at an address less */
145	/* than 0x100, so only need to grab low order offset.    */
146	std	r24,__secondary_hold_acknowledge@l(0)
147	sync
148
149	/* All secondary cpus wait here until told to start. */
150100:	ld	r4,__secondary_hold_spinloop@l(0)
151	cmpdi	0,r4,1
152	bne	100b
153
154#if defined(CONFIG_SMP) || defined(CONFIG_KEXEC)
155	LOAD_REG_IMMEDIATE(r4, .pSeries_secondary_smp_init)
156	mtctr	r4
157	mr	r3,r24
158	bctr
159#else
160	BUG_OPCODE
161#endif
162
163/* This value is used to mark exception frames on the stack. */
164	.section ".toc","aw"
165exception_marker:
166	.tc	ID_72656773_68657265[TC],0x7265677368657265
167	.text
168
169/*
170 * The following macros define the code that appears as
171 * the prologue to each of the exception handlers.  They
172 * are split into two parts to allow a single kernel binary
173 * to be used for pSeries and iSeries.
174 * LOL.  One day... - paulus
175 */
176
177/*
178 * We make as much of the exception code common between native
179 * exception handlers (including pSeries LPAR) and iSeries LPAR
180 * implementations as possible.
181 */
182
183/*
184 * This is the start of the interrupt handlers for pSeries
185 * This code runs with relocation off.
186 */
187#define EX_R9		0
188#define EX_R10		8
189#define EX_R11		16
190#define EX_R12		24
191#define EX_R13		32
192#define EX_SRR0		40
193#define EX_DAR		48
194#define EX_DSISR	56
195#define EX_CCR		60
196#define EX_R3		64
197#define EX_LR		72
198
199/*
200 * We're short on space and time in the exception prolog, so we can't
201 * use the normal SET_REG_IMMEDIATE macro. Normally we just need the
202 * low halfword of the address, but for Kdump we need the whole low
203 * word.
204 */
205#ifdef CONFIG_CRASH_DUMP
206#define LOAD_HANDLER(reg, label)					\
207	oris	reg,reg,(label)@h;	/* virt addr of handler ... */	\
208	ori	reg,reg,(label)@l;	/* .. and the rest */
209#else
210#define LOAD_HANDLER(reg, label)					\
211	ori	reg,reg,(label)@l;	/* virt addr of handler ... */
212#endif
213
214#define EXCEPTION_PROLOG_PSERIES(area, label)				\
215	mfspr	r13,SPRN_SPRG3;		/* get paca address into r13 */	\
216	std	r9,area+EX_R9(r13);	/* save r9 - r12 */		\
217	std	r10,area+EX_R10(r13);					\
218	std	r11,area+EX_R11(r13);					\
219	std	r12,area+EX_R12(r13);					\
220	mfspr	r9,SPRN_SPRG1;						\
221	std	r9,area+EX_R13(r13);					\
222	mfcr	r9;							\
223	clrrdi	r12,r13,32;		/* get high part of &label */	\
224	mfmsr	r10;							\
225	mfspr	r11,SPRN_SRR0;		/* save SRR0 */			\
226	LOAD_HANDLER(r12,label)						\
227	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI;				\
228	mtspr	SPRN_SRR0,r12;						\
229	mfspr	r12,SPRN_SRR1;		/* and SRR1 */			\
230	mtspr	SPRN_SRR1,r10;						\
231	rfid;								\
232	b	.	/* prevent speculative execution */
233
234/*
235 * This is the start of the interrupt handlers for iSeries
236 * This code runs with relocation on.
237 */
238#define EXCEPTION_PROLOG_ISERIES_1(area)				\
239	mfspr	r13,SPRN_SPRG3;		/* get paca address into r13 */	\
240	std	r9,area+EX_R9(r13);	/* save r9 - r12 */		\
241	std	r10,area+EX_R10(r13);					\
242	std	r11,area+EX_R11(r13);					\
243	std	r12,area+EX_R12(r13);					\
244	mfspr	r9,SPRN_SPRG1;						\
245	std	r9,area+EX_R13(r13);					\
246	mfcr	r9
247
248#define EXCEPTION_PROLOG_ISERIES_2					\
249	mfmsr	r10;							\
250	ld	r12,PACALPPACAPTR(r13);					\
251	ld	r11,LPPACASRR0(r12);					\
252	ld	r12,LPPACASRR1(r12);					\
253	ori	r10,r10,MSR_RI;						\
254	mtmsrd	r10,1
255
256/*
257 * The common exception prolog is used for all except a few exceptions
258 * such as a segment miss on a kernel address.  We have to be prepared
259 * to take another exception from the point where we first touch the
260 * kernel stack onwards.
261 *
262 * On entry r13 points to the paca, r9-r13 are saved in the paca,
263 * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
264 * SRR1, and relocation is on.
265 */
266#define EXCEPTION_PROLOG_COMMON(n, area)				   \
267	andi.	r10,r12,MSR_PR;		/* See if coming from user	*/ \
268	mr	r10,r1;			/* Save r1			*/ \
269	subi	r1,r1,INT_FRAME_SIZE;	/* alloc frame on kernel stack	*/ \
270	beq-	1f;							   \
271	ld	r1,PACAKSAVE(r13);	/* kernel stack to use		*/ \
2721:	cmpdi	cr1,r1,0;		/* check if r1 is in userspace	*/ \
273	bge-	cr1,bad_stack;		/* abort if it is		*/ \
274	std	r9,_CCR(r1);		/* save CR in stackframe	*/ \
275	std	r11,_NIP(r1);		/* save SRR0 in stackframe	*/ \
276	std	r12,_MSR(r1);		/* save SRR1 in stackframe	*/ \
277	std	r10,0(r1);		/* make stack chain pointer	*/ \
278	std	r0,GPR0(r1);		/* save r0 in stackframe	*/ \
279	std	r10,GPR1(r1);		/* save r1 in stackframe	*/ \
280	ACCOUNT_CPU_USER_ENTRY(r9, r10);				   \
281	std	r2,GPR2(r1);		/* save r2 in stackframe	*/ \
282	SAVE_4GPRS(3, r1);		/* save r3 - r6 in stackframe	*/ \
283	SAVE_2GPRS(7, r1);		/* save r7, r8 in stackframe	*/ \
284	ld	r9,area+EX_R9(r13);	/* move r9, r10 to stackframe	*/ \
285	ld	r10,area+EX_R10(r13);					   \
286	std	r9,GPR9(r1);						   \
287	std	r10,GPR10(r1);						   \
288	ld	r9,area+EX_R11(r13);	/* move r11 - r13 to stackframe	*/ \
289	ld	r10,area+EX_R12(r13);					   \
290	ld	r11,area+EX_R13(r13);					   \
291	std	r9,GPR11(r1);						   \
292	std	r10,GPR12(r1);						   \
293	std	r11,GPR13(r1);						   \
294	ld	r2,PACATOC(r13);	/* get kernel TOC into r2	*/ \
295	mflr	r9;			/* save LR in stackframe	*/ \
296	std	r9,_LINK(r1);						   \
297	mfctr	r10;			/* save CTR in stackframe	*/ \
298	std	r10,_CTR(r1);						   \
299	mfspr	r11,SPRN_XER;		/* save XER in stackframe	*/ \
300	std	r11,_XER(r1);						   \
301	li	r9,(n)+1;						   \
302	std	r9,_TRAP(r1);		/* set trap number		*/ \
303	li	r10,0;							   \
304	ld	r11,exception_marker@toc(r2);				   \
305	std	r10,RESULT(r1);		/* clear regs->result		*/ \
306	std	r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame	*/
307
308/*
309 * Exception vectors.
310 */
311#define STD_EXCEPTION_PSERIES(n, label)			\
312	. = n;						\
313	.globl label##_pSeries;				\
314label##_pSeries:					\
315	HMT_MEDIUM;					\
316	mtspr	SPRN_SPRG1,r13;		/* save r13 */	\
317	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common)
318
319#define STD_EXCEPTION_ISERIES(n, label, area)		\
320	.globl label##_iSeries;				\
321label##_iSeries:					\
322	HMT_MEDIUM;					\
323	mtspr	SPRN_SPRG1,r13;		/* save r13 */	\
324	EXCEPTION_PROLOG_ISERIES_1(area);		\
325	EXCEPTION_PROLOG_ISERIES_2;			\
326	b	label##_common
327
328#define MASKABLE_EXCEPTION_ISERIES(n, label)				\
329	.globl label##_iSeries;						\
330label##_iSeries:							\
331	HMT_MEDIUM;							\
332	mtspr	SPRN_SPRG1,r13;		/* save r13 */			\
333	EXCEPTION_PROLOG_ISERIES_1(PACA_EXGEN);				\
334	lbz	r10,PACAPROCENABLED(r13);				\
335	cmpwi	0,r10,0;						\
336	beq-	label##_iSeries_masked;					\
337	EXCEPTION_PROLOG_ISERIES_2;					\
338	b	label##_common;						\
339
340#ifdef DO_SOFT_DISABLE
341#define DISABLE_INTS				\
342	lbz	r10,PACAPROCENABLED(r13);	\
343	li	r11,0;				\
344	std	r10,SOFTE(r1);			\
345	mfmsr	r10;				\
346	stb	r11,PACAPROCENABLED(r13);	\
347	ori	r10,r10,MSR_EE;			\
348	mtmsrd	r10,1
349
350#define ENABLE_INTS				\
351	lbz	r10,PACAPROCENABLED(r13);	\
352	mfmsr	r11;				\
353	std	r10,SOFTE(r1);			\
354	ori	r11,r11,MSR_EE;			\
355	mtmsrd	r11,1
356
357#else	/* hard enable/disable interrupts */
358#define DISABLE_INTS
359
360#define ENABLE_INTS				\
361	ld	r12,_MSR(r1);			\
362	mfmsr	r11;				\
363	rlwimi	r11,r12,0,MSR_EE;		\
364	mtmsrd	r11,1
365
366#endif
367
368#define STD_EXCEPTION_COMMON(trap, label, hdlr)		\
369	.align	7;					\
370	.globl label##_common;				\
371label##_common:						\
372	EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);	\
373	DISABLE_INTS;					\
374	bl	.save_nvgprs;				\
375	addi	r3,r1,STACK_FRAME_OVERHEAD;		\
376	bl	hdlr;					\
377	b	.ret_from_except
378
379#define STD_EXCEPTION_COMMON_LITE(trap, label, hdlr)	\
380	.align	7;					\
381	.globl label##_common;				\
382label##_common:						\
383	EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);	\
384	DISABLE_INTS;					\
385	bl	.ppc64_runlatch_on;			\
386	addi	r3,r1,STACK_FRAME_OVERHEAD;		\
387	bl	hdlr;					\
388	b	.ret_from_except_lite
389
390/*
391 * Start of pSeries system interrupt routines
392 */
393	. = 0x100
394	.globl __start_interrupts
395__start_interrupts:
396
397	STD_EXCEPTION_PSERIES(0x100, system_reset)
398
399	. = 0x200
400_machine_check_pSeries:
401	HMT_MEDIUM
402	mtspr	SPRN_SPRG1,r13		/* save r13 */
403	EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common)
404
405	. = 0x300
406	.globl data_access_pSeries
407data_access_pSeries:
408	HMT_MEDIUM
409	mtspr	SPRN_SPRG1,r13
410BEGIN_FTR_SECTION
411	mtspr	SPRN_SPRG2,r12
412	mfspr	r13,SPRN_DAR
413	mfspr	r12,SPRN_DSISR
414	srdi	r13,r13,60
415	rlwimi	r13,r12,16,0x20
416	mfcr	r12
417	cmpwi	r13,0x2c
418	beq	.do_stab_bolted_pSeries
419	mtcrf	0x80,r12
420	mfspr	r12,SPRN_SPRG2
421END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
422	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, data_access_common)
423
424	. = 0x380
425	.globl data_access_slb_pSeries
426data_access_slb_pSeries:
427	HMT_MEDIUM
428	mtspr	SPRN_SPRG1,r13
429	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
430	std	r3,PACA_EXSLB+EX_R3(r13)
431	mfspr	r3,SPRN_DAR
432	std	r9,PACA_EXSLB+EX_R9(r13)	/* save r9 - r12 */
433	mfcr	r9
434#ifdef __DISABLED__
435	/* Keep that around for when we re-implement dynamic VSIDs */
436	cmpdi	r3,0
437	bge	slb_miss_user_pseries
438#endif /* __DISABLED__ */
439	std	r10,PACA_EXSLB+EX_R10(r13)
440	std	r11,PACA_EXSLB+EX_R11(r13)
441	std	r12,PACA_EXSLB+EX_R12(r13)
442	mfspr	r10,SPRN_SPRG1
443	std	r10,PACA_EXSLB+EX_R13(r13)
444	mfspr	r12,SPRN_SRR1		/* and SRR1 */
445	b	.slb_miss_realmode	/* Rel. branch works in real mode */
446
447	STD_EXCEPTION_PSERIES(0x400, instruction_access)
448
449	. = 0x480
450	.globl instruction_access_slb_pSeries
451instruction_access_slb_pSeries:
452	HMT_MEDIUM
453	mtspr	SPRN_SPRG1,r13
454	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
455	std	r3,PACA_EXSLB+EX_R3(r13)
456	mfspr	r3,SPRN_SRR0		/* SRR0 is faulting address */
457	std	r9,PACA_EXSLB+EX_R9(r13)	/* save r9 - r12 */
458	mfcr	r9
459#ifdef __DISABLED__
460	/* Keep that around for when we re-implement dynamic VSIDs */
461	cmpdi	r3,0
462	bge	slb_miss_user_pseries
463#endif /* __DISABLED__ */
464	std	r10,PACA_EXSLB+EX_R10(r13)
465	std	r11,PACA_EXSLB+EX_R11(r13)
466	std	r12,PACA_EXSLB+EX_R12(r13)
467	mfspr	r10,SPRN_SPRG1
468	std	r10,PACA_EXSLB+EX_R13(r13)
469	mfspr	r12,SPRN_SRR1		/* and SRR1 */
470	b	.slb_miss_realmode	/* Rel. branch works in real mode */
471
472	STD_EXCEPTION_PSERIES(0x500, hardware_interrupt)
473	STD_EXCEPTION_PSERIES(0x600, alignment)
474	STD_EXCEPTION_PSERIES(0x700, program_check)
475	STD_EXCEPTION_PSERIES(0x800, fp_unavailable)
476	STD_EXCEPTION_PSERIES(0x900, decrementer)
477	STD_EXCEPTION_PSERIES(0xa00, trap_0a)
478	STD_EXCEPTION_PSERIES(0xb00, trap_0b)
479
480	. = 0xc00
481	.globl	system_call_pSeries
482system_call_pSeries:
483	HMT_MEDIUM
484	mr	r9,r13
485	mfmsr	r10
486	mfspr	r13,SPRN_SPRG3
487	mfspr	r11,SPRN_SRR0
488	clrrdi	r12,r13,32
489	oris	r12,r12,system_call_common@h
490	ori	r12,r12,system_call_common@l
491	mtspr	SPRN_SRR0,r12
492	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI
493	mfspr	r12,SPRN_SRR1
494	mtspr	SPRN_SRR1,r10
495	rfid
496	b	.	/* prevent speculative execution */
497
498	STD_EXCEPTION_PSERIES(0xd00, single_step)
499	STD_EXCEPTION_PSERIES(0xe00, trap_0e)
500
501	/* We need to deal with the Altivec unavailable exception
502	 * here which is at 0xf20, thus in the middle of the
503	 * prolog code of the PerformanceMonitor one. A little
504	 * trickery is thus necessary
505	 */
506	. = 0xf00
507	b	performance_monitor_pSeries
508
509	STD_EXCEPTION_PSERIES(0xf20, altivec_unavailable)
510
511	STD_EXCEPTION_PSERIES(0x1300, instruction_breakpoint)
512	STD_EXCEPTION_PSERIES(0x1700, altivec_assist)
513
514	. = 0x3000
515
516/*** pSeries interrupt support ***/
517
518	/* moved from 0xf00 */
519	STD_EXCEPTION_PSERIES(., performance_monitor)
520
521	.align	7
522_GLOBAL(do_stab_bolted_pSeries)
523	mtcrf	0x80,r12
524	mfspr	r12,SPRN_SPRG2
525	EXCEPTION_PROLOG_PSERIES(PACA_EXSLB, .do_stab_bolted)
526
527/*
528 * We have some room here  we use that to put
529 * the peries slb miss user trampoline code so it's reasonably
530 * away from slb_miss_user_common to avoid problems with rfid
531 *
532 * This is used for when the SLB miss handler has to go virtual,
533 * which doesn't happen for now anymore but will once we re-implement
534 * dynamic VSIDs for shared page tables
535 */
536#ifdef __DISABLED__
537slb_miss_user_pseries:
538	std	r10,PACA_EXGEN+EX_R10(r13)
539	std	r11,PACA_EXGEN+EX_R11(r13)
540	std	r12,PACA_EXGEN+EX_R12(r13)
541	mfspr	r10,SPRG1
542	ld	r11,PACA_EXSLB+EX_R9(r13)
543	ld	r12,PACA_EXSLB+EX_R3(r13)
544	std	r10,PACA_EXGEN+EX_R13(r13)
545	std	r11,PACA_EXGEN+EX_R9(r13)
546	std	r12,PACA_EXGEN+EX_R3(r13)
547	clrrdi	r12,r13,32
548	mfmsr	r10
549	mfspr	r11,SRR0			/* save SRR0 */
550	ori	r12,r12,slb_miss_user_common@l	/* virt addr of handler */
551	ori	r10,r10,MSR_IR|MSR_DR|MSR_RI
552	mtspr	SRR0,r12
553	mfspr	r12,SRR1			/* and SRR1 */
554	mtspr	SRR1,r10
555	rfid
556	b	.				/* prevent spec. execution */
557#endif /* __DISABLED__ */
558
559/*
560 * Vectors for the FWNMI option.  Share common code.
561 */
562	.globl system_reset_fwnmi
563      .align 7
564system_reset_fwnmi:
565	HMT_MEDIUM
566	mtspr	SPRN_SPRG1,r13		/* save r13 */
567	EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common)
568
569	.globl machine_check_fwnmi
570      .align 7
571machine_check_fwnmi:
572	HMT_MEDIUM
573	mtspr	SPRN_SPRG1,r13		/* save r13 */
574	EXCEPTION_PROLOG_PSERIES(PACA_EXMC, machine_check_common)
575
576#ifdef CONFIG_PPC_ISERIES
577/***  ISeries-LPAR interrupt handlers ***/
578
579	STD_EXCEPTION_ISERIES(0x200, machine_check, PACA_EXMC)
580
581	.globl data_access_iSeries
582data_access_iSeries:
583	mtspr	SPRN_SPRG1,r13
584BEGIN_FTR_SECTION
585	mtspr	SPRN_SPRG2,r12
586	mfspr	r13,SPRN_DAR
587	mfspr	r12,SPRN_DSISR
588	srdi	r13,r13,60
589	rlwimi	r13,r12,16,0x20
590	mfcr	r12
591	cmpwi	r13,0x2c
592	beq	.do_stab_bolted_iSeries
593	mtcrf	0x80,r12
594	mfspr	r12,SPRN_SPRG2
595END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
596	EXCEPTION_PROLOG_ISERIES_1(PACA_EXGEN)
597	EXCEPTION_PROLOG_ISERIES_2
598	b	data_access_common
599
600.do_stab_bolted_iSeries:
601	mtcrf	0x80,r12
602	mfspr	r12,SPRN_SPRG2
603	EXCEPTION_PROLOG_ISERIES_1(PACA_EXSLB)
604	EXCEPTION_PROLOG_ISERIES_2
605	b	.do_stab_bolted
606
607	.globl	data_access_slb_iSeries
608data_access_slb_iSeries:
609	mtspr	SPRN_SPRG1,r13		/* save r13 */
610	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
611	std	r3,PACA_EXSLB+EX_R3(r13)
612	mfspr	r3,SPRN_DAR
613	std	r9,PACA_EXSLB+EX_R9(r13)
614	mfcr	r9
615#ifdef __DISABLED__
616	cmpdi	r3,0
617	bge	slb_miss_user_iseries
618#endif
619	std	r10,PACA_EXSLB+EX_R10(r13)
620	std	r11,PACA_EXSLB+EX_R11(r13)
621	std	r12,PACA_EXSLB+EX_R12(r13)
622	mfspr	r10,SPRN_SPRG1
623	std	r10,PACA_EXSLB+EX_R13(r13)
624	ld	r12,PACALPPACAPTR(r13)
625	ld	r12,LPPACASRR1(r12)
626	b	.slb_miss_realmode
627
628	STD_EXCEPTION_ISERIES(0x400, instruction_access, PACA_EXGEN)
629
630	.globl	instruction_access_slb_iSeries
631instruction_access_slb_iSeries:
632	mtspr	SPRN_SPRG1,r13		/* save r13 */
633	mfspr	r13,SPRN_SPRG3		/* get paca address into r13 */
634	std	r3,PACA_EXSLB+EX_R3(r13)
635	ld	r3,PACALPPACAPTR(r13)
636	ld	r3,LPPACASRR0(r3)	/* get SRR0 value */
637	std	r9,PACA_EXSLB+EX_R9(r13)
638	mfcr	r9
639#ifdef __DISABLED__
640	cmpdi	r3,0
641	bge	.slb_miss_user_iseries
642#endif
643	std	r10,PACA_EXSLB+EX_R10(r13)
644	std	r11,PACA_EXSLB+EX_R11(r13)
645	std	r12,PACA_EXSLB+EX_R12(r13)
646	mfspr	r10,SPRN_SPRG1
647	std	r10,PACA_EXSLB+EX_R13(r13)
648	ld	r12,PACALPPACAPTR(r13)
649	ld	r12,LPPACASRR1(r12)
650	b	.slb_miss_realmode
651
652#ifdef __DISABLED__
653slb_miss_user_iseries:
654	std	r10,PACA_EXGEN+EX_R10(r13)
655	std	r11,PACA_EXGEN+EX_R11(r13)
656	std	r12,PACA_EXGEN+EX_R12(r13)
657	mfspr	r10,SPRG1
658	ld	r11,PACA_EXSLB+EX_R9(r13)
659	ld	r12,PACA_EXSLB+EX_R3(r13)
660	std	r10,PACA_EXGEN+EX_R13(r13)
661	std	r11,PACA_EXGEN+EX_R9(r13)
662	std	r12,PACA_EXGEN+EX_R3(r13)
663	EXCEPTION_PROLOG_ISERIES_2
664	b	slb_miss_user_common
665#endif
666
667	MASKABLE_EXCEPTION_ISERIES(0x500, hardware_interrupt)
668	STD_EXCEPTION_ISERIES(0x600, alignment, PACA_EXGEN)
669	STD_EXCEPTION_ISERIES(0x700, program_check, PACA_EXGEN)
670	STD_EXCEPTION_ISERIES(0x800, fp_unavailable, PACA_EXGEN)
671	MASKABLE_EXCEPTION_ISERIES(0x900, decrementer)
672	STD_EXCEPTION_ISERIES(0xa00, trap_0a, PACA_EXGEN)
673	STD_EXCEPTION_ISERIES(0xb00, trap_0b, PACA_EXGEN)
674
675	.globl	system_call_iSeries
676system_call_iSeries:
677	mr	r9,r13
678	mfspr	r13,SPRN_SPRG3
679	EXCEPTION_PROLOG_ISERIES_2
680	b	system_call_common
681
682	STD_EXCEPTION_ISERIES( 0xd00, single_step, PACA_EXGEN)
683	STD_EXCEPTION_ISERIES( 0xe00, trap_0e, PACA_EXGEN)
684	STD_EXCEPTION_ISERIES( 0xf00, performance_monitor, PACA_EXGEN)
685
686	.globl system_reset_iSeries
687system_reset_iSeries:
688	mfspr	r13,SPRN_SPRG3		/* Get paca address */
689	mfmsr	r24
690	ori	r24,r24,MSR_RI
691	mtmsrd	r24			/* RI on */
692	lhz	r24,PACAPACAINDEX(r13)	/* Get processor # */
693	cmpwi	0,r24,0			/* Are we processor 0? */
694	beq	.__start_initialization_iSeries	/* Start up the first processor */
695	mfspr	r4,SPRN_CTRLF
696	li	r5,CTRL_RUNLATCH	/* Turn off the run light */
697	andc	r4,r4,r5
698	mtspr	SPRN_CTRLT,r4
699
7001:
701	HMT_LOW
702#ifdef CONFIG_SMP
703	lbz	r23,PACAPROCSTART(r13)	/* Test if this processor
704					 * should start */
705	sync
706	LOAD_REG_IMMEDIATE(r3,current_set)
707	sldi	r28,r24,3		/* get current_set[cpu#] */
708	ldx	r3,r3,r28
709	addi	r1,r3,THREAD_SIZE
710	subi	r1,r1,STACK_FRAME_OVERHEAD
711
712	cmpwi	0,r23,0
713	beq	iSeries_secondary_smp_loop	/* Loop until told to go */
714	bne	.__secondary_start		/* Loop until told to go */
715iSeries_secondary_smp_loop:
716	/* Let the Hypervisor know we are alive */
717	/* 8002 is a call to HvCallCfg::getLps, a harmless Hypervisor function */
718	lis	r3,0x8002
719	rldicr	r3,r3,32,15		/* r0 = (r3 << 32) & 0xffff000000000000 */
720#else /* CONFIG_SMP */
721	/* Yield the processor.  This is required for non-SMP kernels
722		which are running on multi-threaded machines. */
723	lis	r3,0x8000
724	rldicr	r3,r3,32,15		/* r3 = (r3 << 32) & 0xffff000000000000 */
725	addi	r3,r3,18		/* r3 = 0x8000000000000012 which is "yield" */
726	li	r4,0			/* "yield timed" */
727	li	r5,-1			/* "yield forever" */
728#endif /* CONFIG_SMP */
729	li	r0,-1			/* r0=-1 indicates a Hypervisor call */
730	sc				/* Invoke the hypervisor via a system call */
731	mfspr	r13,SPRN_SPRG3		/* Put r13 back ???? */
732	b	1b			/* If SMP not configured, secondaries
733					 * loop forever */
734
735	.globl decrementer_iSeries_masked
736decrementer_iSeries_masked:
737	/* We may not have a valid TOC pointer in here. */
738	li	r11,1
739	ld	r12,PACALPPACAPTR(r13)
740	stb	r11,LPPACADECRINT(r12)
741	LOAD_REG_IMMEDIATE(r12, tb_ticks_per_jiffy)
742	lwz	r12,0(r12)
743	mtspr	SPRN_DEC,r12
744	/* fall through */
745
746	.globl hardware_interrupt_iSeries_masked
747hardware_interrupt_iSeries_masked:
748	mtcrf	0x80,r9		/* Restore regs */
749	ld	r12,PACALPPACAPTR(r13)
750	ld	r11,LPPACASRR0(r12)
751	ld	r12,LPPACASRR1(r12)
752	mtspr	SPRN_SRR0,r11
753	mtspr	SPRN_SRR1,r12
754	ld	r9,PACA_EXGEN+EX_R9(r13)
755	ld	r10,PACA_EXGEN+EX_R10(r13)
756	ld	r11,PACA_EXGEN+EX_R11(r13)
757	ld	r12,PACA_EXGEN+EX_R12(r13)
758	ld	r13,PACA_EXGEN+EX_R13(r13)
759	rfid
760	b	.	/* prevent speculative execution */
761#endif /* CONFIG_PPC_ISERIES */
762
763/*** Common interrupt handlers ***/
764
765	STD_EXCEPTION_COMMON(0x100, system_reset, .system_reset_exception)
766
767	/*
768	 * Machine check is different because we use a different
769	 * save area: PACA_EXMC instead of PACA_EXGEN.
770	 */
771	.align	7
772	.globl machine_check_common
773machine_check_common:
774	EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
775	DISABLE_INTS
776	bl	.save_nvgprs
777	addi	r3,r1,STACK_FRAME_OVERHEAD
778	bl	.machine_check_exception
779	b	.ret_from_except
780
781	STD_EXCEPTION_COMMON_LITE(0x900, decrementer, .timer_interrupt)
782	STD_EXCEPTION_COMMON(0xa00, trap_0a, .unknown_exception)
783	STD_EXCEPTION_COMMON(0xb00, trap_0b, .unknown_exception)
784	STD_EXCEPTION_COMMON(0xd00, single_step, .single_step_exception)
785	STD_EXCEPTION_COMMON(0xe00, trap_0e, .unknown_exception)
786	STD_EXCEPTION_COMMON(0xf00, performance_monitor, .performance_monitor_exception)
787	STD_EXCEPTION_COMMON(0x1300, instruction_breakpoint, .instruction_breakpoint_exception)
788#ifdef CONFIG_ALTIVEC
789	STD_EXCEPTION_COMMON(0x1700, altivec_assist, .altivec_assist_exception)
790#else
791	STD_EXCEPTION_COMMON(0x1700, altivec_assist, .unknown_exception)
792#endif
793
794/*
795 * Here we have detected that the kernel stack pointer is bad.
796 * R9 contains the saved CR, r13 points to the paca,
797 * r10 contains the (bad) kernel stack pointer,
798 * r11 and r12 contain the saved SRR0 and SRR1.
799 * We switch to using an emergency stack, save the registers there,
800 * and call kernel_bad_stack(), which panics.
801 */
802bad_stack:
803	ld	r1,PACAEMERGSP(r13)
804	subi	r1,r1,64+INT_FRAME_SIZE
805	std	r9,_CCR(r1)
806	std	r10,GPR1(r1)
807	std	r11,_NIP(r1)
808	std	r12,_MSR(r1)
809	mfspr	r11,SPRN_DAR
810	mfspr	r12,SPRN_DSISR
811	std	r11,_DAR(r1)
812	std	r12,_DSISR(r1)
813	mflr	r10
814	mfctr	r11
815	mfxer	r12
816	std	r10,_LINK(r1)
817	std	r11,_CTR(r1)
818	std	r12,_XER(r1)
819	SAVE_GPR(0,r1)
820	SAVE_GPR(2,r1)
821	SAVE_4GPRS(3,r1)
822	SAVE_2GPRS(7,r1)
823	SAVE_10GPRS(12,r1)
824	SAVE_10GPRS(22,r1)
825	addi	r11,r1,INT_FRAME_SIZE
826	std	r11,0(r1)
827	li	r12,0
828	std	r12,0(r11)
829	ld	r2,PACATOC(r13)
8301:	addi	r3,r1,STACK_FRAME_OVERHEAD
831	bl	.kernel_bad_stack
832	b	1b
833
834/*
835 * Return from an exception with minimal checks.
836 * The caller is assumed to have done EXCEPTION_PROLOG_COMMON.
837 * If interrupts have been enabled, or anything has been
838 * done that might have changed the scheduling status of
839 * any task or sent any task a signal, you should use
840 * ret_from_except or ret_from_except_lite instead of this.
841 */
842	.globl	fast_exception_return
843fast_exception_return:
844	ld	r12,_MSR(r1)
845	ld	r11,_NIP(r1)
846	andi.	r3,r12,MSR_RI		/* check if RI is set */
847	beq-	unrecov_fer
848
849#ifdef CONFIG_VIRT_CPU_ACCOUNTING
850	andi.	r3,r12,MSR_PR
851	beq	2f
852	ACCOUNT_CPU_USER_EXIT(r3, r4)
8532:
854#endif
855
856	ld	r3,_CCR(r1)
857	ld	r4,_LINK(r1)
858	ld	r5,_CTR(r1)
859	ld	r6,_XER(r1)
860	mtcr	r3
861	mtlr	r4
862	mtctr	r5
863	mtxer	r6
864	REST_GPR(0, r1)
865	REST_8GPRS(2, r1)
866
867	mfmsr	r10
868	clrrdi	r10,r10,2		/* clear RI (LE is 0 already) */
869	mtmsrd	r10,1
870
871	mtspr	SPRN_SRR1,r12
872	mtspr	SPRN_SRR0,r11
873	REST_4GPRS(10, r1)
874	ld	r1,GPR1(r1)
875	rfid
876	b	.	/* prevent speculative execution */
877
878unrecov_fer:
879	bl	.save_nvgprs
8801:	addi	r3,r1,STACK_FRAME_OVERHEAD
881	bl	.unrecoverable_exception
882	b	1b
883
884/*
885 * Here r13 points to the paca, r9 contains the saved CR,
886 * SRR0 and SRR1 are saved in r11 and r12,
887 * r9 - r13 are saved in paca->exgen.
888 */
889	.align	7
890	.globl data_access_common
891data_access_common:
892	mfspr	r10,SPRN_DAR
893	std	r10,PACA_EXGEN+EX_DAR(r13)
894	mfspr	r10,SPRN_DSISR
895	stw	r10,PACA_EXGEN+EX_DSISR(r13)
896	EXCEPTION_PROLOG_COMMON(0x300, PACA_EXGEN)
897	ld	r3,PACA_EXGEN+EX_DAR(r13)
898	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
899	li	r5,0x300
900	b	.do_hash_page	 	/* Try to handle as hpte fault */
901
902	.align	7
903	.globl instruction_access_common
904instruction_access_common:
905	EXCEPTION_PROLOG_COMMON(0x400, PACA_EXGEN)
906	ld	r3,_NIP(r1)
907	andis.	r4,r12,0x5820
908	li	r5,0x400
909	b	.do_hash_page		/* Try to handle as hpte fault */
910
911/*
912 * Here is the common SLB miss user that is used when going to virtual
913 * mode for SLB misses, that is currently not used
914 */
915#ifdef __DISABLED__
916	.align	7
917	.globl	slb_miss_user_common
918slb_miss_user_common:
919	mflr	r10
920	std	r3,PACA_EXGEN+EX_DAR(r13)
921	stw	r9,PACA_EXGEN+EX_CCR(r13)
922	std	r10,PACA_EXGEN+EX_LR(r13)
923	std	r11,PACA_EXGEN+EX_SRR0(r13)
924	bl	.slb_allocate_user
925
926	ld	r10,PACA_EXGEN+EX_LR(r13)
927	ld	r3,PACA_EXGEN+EX_R3(r13)
928	lwz	r9,PACA_EXGEN+EX_CCR(r13)
929	ld	r11,PACA_EXGEN+EX_SRR0(r13)
930	mtlr	r10
931	beq-	slb_miss_fault
932
933	andi.	r10,r12,MSR_RI		/* check for unrecoverable exception */
934	beq-	unrecov_user_slb
935	mfmsr	r10
936
937.machine push
938.machine "power4"
939	mtcrf	0x80,r9
940.machine pop
941
942	clrrdi	r10,r10,2		/* clear RI before setting SRR0/1 */
943	mtmsrd	r10,1
944
945	mtspr	SRR0,r11
946	mtspr	SRR1,r12
947
948	ld	r9,PACA_EXGEN+EX_R9(r13)
949	ld	r10,PACA_EXGEN+EX_R10(r13)
950	ld	r11,PACA_EXGEN+EX_R11(r13)
951	ld	r12,PACA_EXGEN+EX_R12(r13)
952	ld	r13,PACA_EXGEN+EX_R13(r13)
953	rfid
954	b	.
955
956slb_miss_fault:
957	EXCEPTION_PROLOG_COMMON(0x380, PACA_EXGEN)
958	ld	r4,PACA_EXGEN+EX_DAR(r13)
959	li	r5,0
960	std	r4,_DAR(r1)
961	std	r5,_DSISR(r1)
962	b	.handle_page_fault
963
964unrecov_user_slb:
965	EXCEPTION_PROLOG_COMMON(0x4200, PACA_EXGEN)
966	DISABLE_INTS
967	bl	.save_nvgprs
9681:	addi	r3,r1,STACK_FRAME_OVERHEAD
969	bl	.unrecoverable_exception
970	b	1b
971
972#endif /* __DISABLED__ */
973
974
975/*
976 * r13 points to the PACA, r9 contains the saved CR,
977 * r12 contain the saved SRR1, SRR0 is still ready for return
978 * r3 has the faulting address
979 * r9 - r13 are saved in paca->exslb.
980 * r3 is saved in paca->slb_r3
981 * We assume we aren't going to take any exceptions during this procedure.
982 */
983_GLOBAL(slb_miss_realmode)
984	mflr	r10
985
986	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
987	std	r10,PACA_EXSLB+EX_LR(r13)	/* save LR */
988
989	bl	.slb_allocate_realmode
990
991	/* All done -- return from exception. */
992
993	ld	r10,PACA_EXSLB+EX_LR(r13)
994	ld	r3,PACA_EXSLB+EX_R3(r13)
995	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
996#ifdef CONFIG_PPC_ISERIES
997	ld	r11,PACALPPACAPTR(r13)
998	ld	r11,LPPACASRR0(r11)		/* get SRR0 value */
999#endif /* CONFIG_PPC_ISERIES */
1000
1001	mtlr	r10
1002
1003	andi.	r10,r12,MSR_RI	/* check for unrecoverable exception */
1004	beq-	unrecov_slb
1005
1006.machine	push
1007.machine	"power4"
1008	mtcrf	0x80,r9
1009	mtcrf	0x01,r9		/* slb_allocate uses cr0 and cr7 */
1010.machine	pop
1011
1012#ifdef CONFIG_PPC_ISERIES
1013	mtspr	SPRN_SRR0,r11
1014	mtspr	SPRN_SRR1,r12
1015#endif /* CONFIG_PPC_ISERIES */
1016	ld	r9,PACA_EXSLB+EX_R9(r13)
1017	ld	r10,PACA_EXSLB+EX_R10(r13)
1018	ld	r11,PACA_EXSLB+EX_R11(r13)
1019	ld	r12,PACA_EXSLB+EX_R12(r13)
1020	ld	r13,PACA_EXSLB+EX_R13(r13)
1021	rfid
1022	b	.	/* prevent speculative execution */
1023
1024unrecov_slb:
1025	EXCEPTION_PROLOG_COMMON(0x4100, PACA_EXSLB)
1026	DISABLE_INTS
1027	bl	.save_nvgprs
10281:	addi	r3,r1,STACK_FRAME_OVERHEAD
1029	bl	.unrecoverable_exception
1030	b	1b
1031
1032	.align	7
1033	.globl hardware_interrupt_common
1034	.globl hardware_interrupt_entry
1035hardware_interrupt_common:
1036	EXCEPTION_PROLOG_COMMON(0x500, PACA_EXGEN)
1037hardware_interrupt_entry:
1038	DISABLE_INTS
1039	bl	.ppc64_runlatch_on
1040	addi	r3,r1,STACK_FRAME_OVERHEAD
1041	bl	.do_IRQ
1042	b	.ret_from_except_lite
1043
1044	.align	7
1045	.globl alignment_common
1046alignment_common:
1047	mfspr	r10,SPRN_DAR
1048	std	r10,PACA_EXGEN+EX_DAR(r13)
1049	mfspr	r10,SPRN_DSISR
1050	stw	r10,PACA_EXGEN+EX_DSISR(r13)
1051	EXCEPTION_PROLOG_COMMON(0x600, PACA_EXGEN)
1052	ld	r3,PACA_EXGEN+EX_DAR(r13)
1053	lwz	r4,PACA_EXGEN+EX_DSISR(r13)
1054	std	r3,_DAR(r1)
1055	std	r4,_DSISR(r1)
1056	bl	.save_nvgprs
1057	addi	r3,r1,STACK_FRAME_OVERHEAD
1058	ENABLE_INTS
1059	bl	.alignment_exception
1060	b	.ret_from_except
1061
1062	.align	7
1063	.globl program_check_common
1064program_check_common:
1065	EXCEPTION_PROLOG_COMMON(0x700, PACA_EXGEN)
1066	bl	.save_nvgprs
1067	addi	r3,r1,STACK_FRAME_OVERHEAD
1068	ENABLE_INTS
1069	bl	.program_check_exception
1070	b	.ret_from_except
1071
1072	.align	7
1073	.globl fp_unavailable_common
1074fp_unavailable_common:
1075	EXCEPTION_PROLOG_COMMON(0x800, PACA_EXGEN)
1076	bne	.load_up_fpu		/* if from user, just load it up */
1077	bl	.save_nvgprs
1078	addi	r3,r1,STACK_FRAME_OVERHEAD
1079	ENABLE_INTS
1080	bl	.kernel_fp_unavailable_exception
1081	BUG_OPCODE
1082
1083	.align	7
1084	.globl altivec_unavailable_common
1085altivec_unavailable_common:
1086	EXCEPTION_PROLOG_COMMON(0xf20, PACA_EXGEN)
1087#ifdef CONFIG_ALTIVEC
1088BEGIN_FTR_SECTION
1089	bne	.load_up_altivec	/* if from user, just load it up */
1090END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
1091#endif
1092	bl	.save_nvgprs
1093	addi	r3,r1,STACK_FRAME_OVERHEAD
1094	ENABLE_INTS
1095	bl	.altivec_unavailable_exception
1096	b	.ret_from_except
1097
1098#ifdef CONFIG_ALTIVEC
1099/*
1100 * load_up_altivec(unused, unused, tsk)
1101 * Disable VMX for the task which had it previously,
1102 * and save its vector registers in its thread_struct.
1103 * Enables the VMX for use in the kernel on return.
1104 * On SMP we know the VMX is free, since we give it up every
1105 * switch (ie, no lazy save of the vector registers).
1106 * On entry: r13 == 'current' && last_task_used_altivec != 'current'
1107 */
1108_STATIC(load_up_altivec)
1109	mfmsr	r5			/* grab the current MSR */
1110	oris	r5,r5,MSR_VEC@h
1111	mtmsrd	r5			/* enable use of VMX now */
1112	isync
1113
1114/*
1115 * For SMP, we don't do lazy VMX switching because it just gets too
1116 * horrendously complex, especially when a task switches from one CPU
1117 * to another.  Instead we call giveup_altvec in switch_to.
1118 * VRSAVE isn't dealt with here, that is done in the normal context
1119 * switch code. Note that we could rely on vrsave value to eventually
1120 * avoid saving all of the VREGs here...
1121 */
1122#ifndef CONFIG_SMP
1123	ld	r3,last_task_used_altivec@got(r2)
1124	ld	r4,0(r3)
1125	cmpdi	0,r4,0
1126	beq	1f
1127	/* Save VMX state to last_task_used_altivec's THREAD struct */
1128	addi	r4,r4,THREAD
1129	SAVE_32VRS(0,r5,r4)
1130	mfvscr	vr0
1131	li	r10,THREAD_VSCR
1132	stvx	vr0,r10,r4
1133	/* Disable VMX for last_task_used_altivec */
1134	ld	r5,PT_REGS(r4)
1135	ld	r4,_MSR-STACK_FRAME_OVERHEAD(r5)
1136	lis	r6,MSR_VEC@h
1137	andc	r4,r4,r6
1138	std	r4,_MSR-STACK_FRAME_OVERHEAD(r5)
11391:
1140#endif /* CONFIG_SMP */
1141	/* Hack: if we get an altivec unavailable trap with VRSAVE
1142	 * set to all zeros, we assume this is a broken application
1143	 * that fails to set it properly, and thus we switch it to
1144	 * all 1's
1145	 */
1146	mfspr	r4,SPRN_VRSAVE
1147	cmpdi	0,r4,0
1148	bne+	1f
1149	li	r4,-1
1150	mtspr	SPRN_VRSAVE,r4
11511:
1152	/* enable use of VMX after return */
1153	ld	r4,PACACURRENT(r13)
1154	addi	r5,r4,THREAD		/* Get THREAD */
1155	oris	r12,r12,MSR_VEC@h
1156	std	r12,_MSR(r1)
1157	li	r4,1
1158	li	r10,THREAD_VSCR
1159	stw	r4,THREAD_USED_VR(r5)
1160	lvx	vr0,r10,r5
1161	mtvscr	vr0
1162	REST_32VRS(0,r4,r5)
1163#ifndef CONFIG_SMP
1164	/* Update last_task_used_math to 'current' */
1165	subi	r4,r5,THREAD		/* Back to 'current' */
1166	std	r4,0(r3)
1167#endif /* CONFIG_SMP */
1168	/* restore registers and return */
1169	b	fast_exception_return
1170#endif /* CONFIG_ALTIVEC */
1171
1172/*
1173 * Hash table stuff
1174 */
1175	.align	7
1176_GLOBAL(do_hash_page)
1177	std	r3,_DAR(r1)
1178	std	r4,_DSISR(r1)
1179
1180	andis.	r0,r4,0xa450		/* weird error? */
1181	bne-	.handle_page_fault	/* if not, try to insert a HPTE */
1182BEGIN_FTR_SECTION
1183	andis.	r0,r4,0x0020		/* Is it a segment table fault? */
1184	bne-	.do_ste_alloc		/* If so handle it */
1185END_FTR_SECTION_IFCLR(CPU_FTR_SLB)
1186
1187	/*
1188	 * We need to set the _PAGE_USER bit if MSR_PR is set or if we are
1189	 * accessing a userspace segment (even from the kernel). We assume
1190	 * kernel addresses always have the high bit set.
1191	 */
1192	rlwinm	r4,r4,32-25+9,31-9,31-9	/* DSISR_STORE -> _PAGE_RW */
1193	rotldi	r0,r3,15		/* Move high bit into MSR_PR posn */
1194	orc	r0,r12,r0		/* MSR_PR | ~high_bit */
1195	rlwimi	r4,r0,32-13,30,30	/* becomes _PAGE_USER access bit */
1196	ori	r4,r4,1			/* add _PAGE_PRESENT */
1197	rlwimi	r4,r5,22+2,31-2,31-2	/* Set _PAGE_EXEC if trap is 0x400 */
1198
1199	/*
1200	 * On iSeries, we soft-disable interrupts here, then
1201	 * hard-enable interrupts so that the hash_page code can spin on
1202	 * the hash_table_lock without problems on a shared processor.
1203	 */
1204	DISABLE_INTS
1205
1206	/*
1207	 * r3 contains the faulting address
1208	 * r4 contains the required access permissions
1209	 * r5 contains the trap number
1210	 *
1211	 * at return r3 = 0 for success
1212	 */
1213	bl	.hash_page		/* build HPTE if possible */
1214	cmpdi	r3,0			/* see if hash_page succeeded */
1215
1216#ifdef DO_SOFT_DISABLE
1217	/*
1218	 * If we had interrupts soft-enabled at the point where the
1219	 * DSI/ISI occurred, and an interrupt came in during hash_page,
1220	 * handle it now.
1221	 * We jump to ret_from_except_lite rather than fast_exception_return
1222	 * because ret_from_except_lite will check for and handle pending
1223	 * interrupts if necessary.
1224	 */
1225	beq	.ret_from_except_lite
1226	/* For a hash failure, we don't bother re-enabling interrupts */
1227	ble-	12f
1228
1229	/*
1230	 * hash_page couldn't handle it, set soft interrupt enable back
1231	 * to what it was before the trap.  Note that .local_irq_restore
1232	 * handles any interrupts pending at this point.
1233	 */
1234	ld	r3,SOFTE(r1)
1235	bl	.local_irq_restore
1236	b	11f
1237#else
1238	beq	fast_exception_return   /* Return from exception on success */
1239	ble-	12f			/* Failure return from hash_page */
1240
1241	/* fall through */
1242#endif
1243
1244/* Here we have a page fault that hash_page can't handle. */
1245_GLOBAL(handle_page_fault)
1246	ENABLE_INTS
124711:	ld	r4,_DAR(r1)
1248	ld	r5,_DSISR(r1)
1249	addi	r3,r1,STACK_FRAME_OVERHEAD
1250	bl	.do_page_fault
1251	cmpdi	r3,0
1252	beq+	.ret_from_except_lite
1253	bl	.save_nvgprs
1254	mr	r5,r3
1255	addi	r3,r1,STACK_FRAME_OVERHEAD
1256	lwz	r4,_DAR(r1)
1257	bl	.bad_page_fault
1258	b	.ret_from_except
1259
1260/* We have a page fault that hash_page could handle but HV refused
1261 * the PTE insertion
1262 */
126312:	bl	.save_nvgprs
1264	addi	r3,r1,STACK_FRAME_OVERHEAD
1265	lwz	r4,_DAR(r1)
1266	bl	.low_hash_fault
1267	b	.ret_from_except
1268
1269	/* here we have a segment miss */
1270_GLOBAL(do_ste_alloc)
1271	bl	.ste_allocate		/* try to insert stab entry */
1272	cmpdi	r3,0
1273	beq+	fast_exception_return
1274	b	.handle_page_fault
1275
1276/*
1277 * r13 points to the PACA, r9 contains the saved CR,
1278 * r11 and r12 contain the saved SRR0 and SRR1.
1279 * r9 - r13 are saved in paca->exslb.
1280 * We assume we aren't going to take any exceptions during this procedure.
1281 * We assume (DAR >> 60) == 0xc.
1282 */
1283	.align	7
1284_GLOBAL(do_stab_bolted)
1285	stw	r9,PACA_EXSLB+EX_CCR(r13)	/* save CR in exc. frame */
1286	std	r11,PACA_EXSLB+EX_SRR0(r13)	/* save SRR0 in exc. frame */
1287
1288	/* Hash to the primary group */
1289	ld	r10,PACASTABVIRT(r13)
1290	mfspr	r11,SPRN_DAR
1291	srdi	r11,r11,28
1292	rldimi	r10,r11,7,52	/* r10 = first ste of the group */
1293
1294	/* Calculate VSID */
1295	/* This is a kernel address, so protovsid = ESID */
1296	ASM_VSID_SCRAMBLE(r11, r9)
1297	rldic	r9,r11,12,16	/* r9 = vsid << 12 */
1298
1299	/* Search the primary group for a free entry */
13001:	ld	r11,0(r10)	/* Test valid bit of the current ste	*/
1301	andi.	r11,r11,0x80
1302	beq	2f
1303	addi	r10,r10,16
1304	andi.	r11,r10,0x70
1305	bne	1b
1306
1307	/* Stick for only searching the primary group for now.		*/
1308	/* At least for now, we use a very simple random castout scheme */
1309	/* Use the TB as a random number ;  OR in 1 to avoid entry 0	*/
1310	mftb	r11
1311	rldic	r11,r11,4,57	/* r11 = (r11 << 4) & 0x70 */
1312	ori	r11,r11,0x10
1313
1314	/* r10 currently points to an ste one past the group of interest */
1315	/* make it point to the randomly selected entry			*/
1316	subi	r10,r10,128
1317	or 	r10,r10,r11	/* r10 is the entry to invalidate	*/
1318
1319	isync			/* mark the entry invalid		*/
1320	ld	r11,0(r10)
1321	rldicl	r11,r11,56,1	/* clear the valid bit */
1322	rotldi	r11,r11,8
1323	std	r11,0(r10)
1324	sync
1325
1326	clrrdi	r11,r11,28	/* Get the esid part of the ste		*/
1327	slbie	r11
1328
13292:	std	r9,8(r10)	/* Store the vsid part of the ste	*/
1330	eieio
1331
1332	mfspr	r11,SPRN_DAR		/* Get the new esid			*/
1333	clrrdi	r11,r11,28	/* Permits a full 32b of ESID		*/
1334	ori	r11,r11,0x90	/* Turn on valid and kp			*/
1335	std	r11,0(r10)	/* Put new entry back into the stab	*/
1336
1337	sync
1338
1339	/* All done -- return from exception. */
1340	lwz	r9,PACA_EXSLB+EX_CCR(r13)	/* get saved CR */
1341	ld	r11,PACA_EXSLB+EX_SRR0(r13)	/* get saved SRR0 */
1342
1343	andi.	r10,r12,MSR_RI
1344	beq-	unrecov_slb
1345
1346	mtcrf	0x80,r9			/* restore CR */
1347
1348	mfmsr	r10
1349	clrrdi	r10,r10,2
1350	mtmsrd	r10,1
1351
1352	mtspr	SPRN_SRR0,r11
1353	mtspr	SPRN_SRR1,r12
1354	ld	r9,PACA_EXSLB+EX_R9(r13)
1355	ld	r10,PACA_EXSLB+EX_R10(r13)
1356	ld	r11,PACA_EXSLB+EX_R11(r13)
1357	ld	r12,PACA_EXSLB+EX_R12(r13)
1358	ld	r13,PACA_EXSLB+EX_R13(r13)
1359	rfid
1360	b	.	/* prevent speculative execution */
1361
1362/*
1363 * Space for CPU0's segment table.
1364 *
1365 * On iSeries, the hypervisor must fill in at least one entry before
1366 * we get control (with relocate on).  The address is give to the hv
1367 * as a page number (see xLparMap in lpardata.c), so this must be at a
1368 * fixed address (the linker can't compute (u64)&initial_stab >>
1369 * PAGE_SHIFT).
1370 */
1371	. = STAB0_OFFSET	/* 0x6000 */
1372	.globl initial_stab
1373initial_stab:
1374	.space	4096
1375
1376/*
1377 * Data area reserved for FWNMI option.
1378 * This address (0x7000) is fixed by the RPA.
1379 */
1380	.= 0x7000
1381	.globl fwnmi_data_area
1382fwnmi_data_area:
1383
1384	/* iSeries does not use the FWNMI stuff, so it is safe to put
1385	 * this here, even if we later allow kernels that will boot on
1386	 * both pSeries and iSeries */
1387#ifdef CONFIG_PPC_ISERIES
1388        . = LPARMAP_PHYS
1389#include "lparmap.s"
1390/*
1391 * This ".text" is here for old compilers that generate a trailing
1392 * .note section when compiling .c files to .s
1393 */
1394	.text
1395#endif /* CONFIG_PPC_ISERIES */
1396
1397        . = 0x8000
1398
1399/*
1400 * On pSeries, secondary processors spin in the following code.
1401 * At entry, r3 = this processor's number (physical cpu id)
1402 */
1403_GLOBAL(pSeries_secondary_smp_init)
1404	mr	r24,r3
1405
1406	/* turn on 64-bit mode */
1407	bl	.enable_64b_mode
1408	isync
1409
1410	/* Copy some CPU settings from CPU 0 */
1411	bl	.__restore_cpu_setup
1412
1413	/* Set up a paca value for this processor. Since we have the
1414	 * physical cpu id in r24, we need to search the pacas to find
1415	 * which logical id maps to our physical one.
1416	 */
1417	LOAD_REG_IMMEDIATE(r13, paca)	/* Get base vaddr of paca array	 */
1418	li	r5,0			/* logical cpu id                */
14191:	lhz	r6,PACAHWCPUID(r13)	/* Load HW procid from paca      */
1420	cmpw	r6,r24			/* Compare to our id             */
1421	beq	2f
1422	addi	r13,r13,PACA_SIZE	/* Loop to next PACA on miss     */
1423	addi	r5,r5,1
1424	cmpwi	r5,NR_CPUS
1425	blt	1b
1426
1427	mr	r3,r24			/* not found, copy phys to r3	 */
1428	b	.kexec_wait		/* next kernel might do better	 */
1429
14302:	mtspr	SPRN_SPRG3,r13		/* Save vaddr of paca in SPRG3	 */
1431	/* From now on, r24 is expected to be logical cpuid */
1432	mr	r24,r5
14333:	HMT_LOW
1434	lbz	r23,PACAPROCSTART(r13)	/* Test if this processor should */
1435					/* start.			 */
1436	sync
1437
1438	/* Create a temp kernel stack for use before relocation is on.	*/
1439	ld	r1,PACAEMERGSP(r13)
1440	subi	r1,r1,STACK_FRAME_OVERHEAD
1441
1442	cmpwi	0,r23,0
1443#ifdef CONFIG_SMP
1444	bne	.__secondary_start
1445#endif
1446	b 	3b			/* Loop until told to go	 */
1447
1448#ifdef CONFIG_PPC_ISERIES
1449_STATIC(__start_initialization_iSeries)
1450	/* Clear out the BSS */
1451	LOAD_REG_IMMEDIATE(r11,__bss_stop)
1452	LOAD_REG_IMMEDIATE(r8,__bss_start)
1453	sub	r11,r11,r8		/* bss size			*/
1454	addi	r11,r11,7		/* round up to an even double word */
1455	rldicl. r11,r11,61,3		/* shift right by 3		*/
1456	beq	4f
1457	addi	r8,r8,-8
1458	li	r0,0
1459	mtctr	r11			/* zero this many doublewords	*/
14603:	stdu	r0,8(r8)
1461	bdnz	3b
14624:
1463	LOAD_REG_IMMEDIATE(r1,init_thread_union)
1464	addi	r1,r1,THREAD_SIZE
1465	li	r0,0
1466	stdu	r0,-STACK_FRAME_OVERHEAD(r1)
1467
1468	LOAD_REG_IMMEDIATE(r3,cpu_specs)
1469	LOAD_REG_IMMEDIATE(r4,cur_cpu_spec)
1470	li	r5,0
1471	bl	.identify_cpu
1472
1473	LOAD_REG_IMMEDIATE(r2,__toc_start)
1474	addi	r2,r2,0x4000
1475	addi	r2,r2,0x4000
1476
1477	bl	.iSeries_early_setup
1478	bl	.early_setup
1479
1480	/* relocation is on at this point */
1481
1482	b	.start_here_common
1483#endif /* CONFIG_PPC_ISERIES */
1484
1485#ifdef CONFIG_PPC_MULTIPLATFORM
1486
1487_STATIC(__mmu_off)
1488	mfmsr	r3
1489	andi.	r0,r3,MSR_IR|MSR_DR
1490	beqlr
1491	andc	r3,r3,r0
1492	mtspr	SPRN_SRR0,r4
1493	mtspr	SPRN_SRR1,r3
1494	sync
1495	rfid
1496	b	.	/* prevent speculative execution */
1497
1498
1499/*
1500 * Here is our main kernel entry point. We support currently 2 kind of entries
1501 * depending on the value of r5.
1502 *
1503 *   r5 != NULL -> OF entry, we go to prom_init, "legacy" parameter content
1504 *                 in r3...r7
1505 *
1506 *   r5 == NULL -> kexec style entry. r3 is a physical pointer to the
1507 *                 DT block, r4 is a physical pointer to the kernel itself
1508 *
1509 */
1510_GLOBAL(__start_initialization_multiplatform)
1511#ifdef CONFIG_PPC_MULTIPLATFORM
1512	/*
1513	 * Are we booted from a PROM Of-type client-interface ?
1514	 */
1515	cmpldi	cr0,r5,0
1516	bne	.__boot_from_prom		/* yes -> prom */
1517#endif
1518
1519	/* Save parameters */
1520	mr	r31,r3
1521	mr	r30,r4
1522
1523	/* Make sure we are running in 64 bits mode */
1524	bl	.enable_64b_mode
1525
1526	/* Setup some critical 970 SPRs before switching MMU off */
1527	bl	.__970_cpu_preinit
1528
1529	/* cpu # */
1530	li	r24,0
1531
1532	/* Switch off MMU if not already */
1533	LOAD_REG_IMMEDIATE(r4, .__after_prom_start - KERNELBASE)
1534	add	r4,r4,r30
1535	bl	.__mmu_off
1536	b	.__after_prom_start
1537
1538#ifdef CONFIG_PPC_MULTIPLATFORM
1539_STATIC(__boot_from_prom)
1540	/* Save parameters */
1541	mr	r31,r3
1542	mr	r30,r4
1543	mr	r29,r5
1544	mr	r28,r6
1545	mr	r27,r7
1546
1547	/*
1548	 * Align the stack to 16-byte boundary
1549	 * Depending on the size and layout of the ELF sections in the initial
1550	 * boot binary, the stack pointer will be unalignet on PowerMac
1551	 */
1552	rldicr	r1,r1,0,59
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	/* The following gets the stack and TOC set up with the regs */
1822	/* pointing to the real addr of the kernel stack.  This is   */
1823	/* all done to support the C function call below which sets  */
1824	/* up the htab.  This is done because we have relocated the  */
1825	/* kernel but are still running in real mode. */
1826
1827	LOAD_REG_IMMEDIATE(r3,init_thread_union)
1828	add	r3,r3,r26
1829
1830	/* set up a stack pointer (physical address) */
1831	addi	r1,r3,THREAD_SIZE
1832	li	r0,0
1833	stdu	r0,-STACK_FRAME_OVERHEAD(r1)
1834
1835	/* set up the TOC (physical address) */
1836	LOAD_REG_IMMEDIATE(r2,__toc_start)
1837	addi	r2,r2,0x4000
1838	addi	r2,r2,0x4000
1839	add	r2,r2,r26
1840
1841	LOAD_REG_IMMEDIATE(r3, cpu_specs)
1842	add	r3,r3,r26
1843	LOAD_REG_IMMEDIATE(r4,cur_cpu_spec)
1844	add	r4,r4,r26
1845	mr	r5,r26
1846	bl	.identify_cpu
1847
1848	/* Save some low level config HIDs of CPU0 to be copied to
1849	 * other CPUs later on, or used for suspend/resume
1850	 */
1851	bl	.__save_cpu_setup
1852	sync
1853
1854	/* Do very early kernel initializations, including initial hash table,
1855	 * stab and slb setup before we turn on relocation.	*/
1856
1857	/* Restore parameters passed from prom_init/kexec */
1858	mr	r3,r31
1859 	bl	.early_setup
1860
1861	LOAD_REG_IMMEDIATE(r3, .start_here_common)
1862	LOAD_REG_IMMEDIATE(r4, MSR_KERNEL)
1863	mtspr	SPRN_SRR0,r3
1864	mtspr	SPRN_SRR1,r4
1865	rfid
1866	b	.	/* prevent speculative execution */
1867#endif /* CONFIG_PPC_MULTIPLATFORM */
1868
1869	/* This is where all platforms converge execution */
1870_STATIC(start_here_common)
1871	/* relocation is on at this point */
1872
1873	/* The following code sets up the SP and TOC now that we are */
1874	/* running with translation enabled. */
1875
1876	LOAD_REG_IMMEDIATE(r3,init_thread_union)
1877
1878	/* set up the stack */
1879	addi	r1,r3,THREAD_SIZE
1880	li	r0,0
1881	stdu	r0,-STACK_FRAME_OVERHEAD(r1)
1882
1883	/* Apply the CPUs-specific fixups (nop out sections not relevant
1884	 * to this CPU
1885	 */
1886	li	r3,0
1887	bl	.do_cpu_ftr_fixups
1888
1889	LOAD_REG_IMMEDIATE(r26, boot_cpuid)
1890	lwz	r26,0(r26)
1891
1892	LOAD_REG_IMMEDIATE(r24, paca)	/* Get base vaddr of paca array  */
1893	mulli	r13,r26,PACA_SIZE	/* Calculate vaddr of right paca */
1894	add	r13,r13,r24		/* for this processor.		 */
1895	mtspr	SPRN_SPRG3,r13
1896
1897	/* ptr to current */
1898	LOAD_REG_IMMEDIATE(r4, init_task)
1899	std	r4,PACACURRENT(r13)
1900
1901	/* Load the TOC */
1902	ld	r2,PACATOC(r13)
1903	std	r1,PACAKSAVE(r13)
1904
1905	bl	.setup_system
1906
1907	/* Load up the kernel context */
19085:
1909#ifdef DO_SOFT_DISABLE
1910	li	r5,0
1911	stb	r5,PACAPROCENABLED(r13)	/* Soft Disabled */
1912	mfmsr	r5
1913	ori	r5,r5,MSR_EE		/* Hard Enabled */
1914	mtmsrd	r5
1915#endif
1916
1917	bl .start_kernel
1918
1919	/* Not reached */
1920	BUG_OPCODE
1921
1922/* Put the paca pointer into r13 and SPRG3 */
1923_GLOBAL(setup_boot_paca)
1924	LOAD_REG_IMMEDIATE(r3, boot_cpuid)
1925	lwz	r3,0(r3)
1926	LOAD_REG_IMMEDIATE(r4, paca) 	/* Get base vaddr of paca array	 */
1927	mulli	r3,r3,PACA_SIZE		/* Calculate vaddr of right paca */
1928	add	r13,r3,r4		/* for this processor.		 */
1929	mtspr	SPRN_SPRG3,r13
1930
1931	blr
1932
1933/*
1934 * We put a few things here that have to be page-aligned.
1935 * This stuff goes at the beginning of the bss, which is page-aligned.
1936 */
1937	.section ".bss"
1938
1939	.align	PAGE_SHIFT
1940
1941	.globl	empty_zero_page
1942empty_zero_page:
1943	.space	PAGE_SIZE
1944
1945	.globl	swapper_pg_dir
1946swapper_pg_dir:
1947	.space	PAGE_SIZE
1948
1949/*
1950 * This space gets a copy of optional info passed to us by the bootstrap
1951 * Used to pass parameters into the kernel like root=/dev/sda1, etc.
1952 */
1953	.globl	cmd_line
1954cmd_line:
1955	.space	COMMAND_LINE_SIZE
1956