xref: /linux/arch/powerpc/kernel/head_85xx.S (revision 5ac79730324c6f37106ce397586020ffe6e8e234)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * Kernel execution entry point code.
4 *
5 *    Copyright (c) 1995-1996 Gary Thomas <gdt@linuxppc.org>
6 *	Initial PowerPC version.
7 *    Copyright (c) 1996 Cort Dougan <cort@cs.nmt.edu>
8 *	Rewritten for PReP
9 *    Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
10 *	Low-level exception handers, MMU support, and rewrite.
11 *    Copyright (c) 1997 Dan Malek <dmalek@jlc.net>
12 *	PowerPC 8xx modifications.
13 *    Copyright (c) 1998-1999 TiVo, Inc.
14 *	PowerPC 403GCX modifications.
15 *    Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
16 *	PowerPC 403GCX/405GP modifications.
17 *    Copyright 2000 MontaVista Software Inc.
18 *	PPC405 modifications
19 *	PowerPC 403GCX/405GP modifications.
20 *	Author: MontaVista Software, Inc.
21 *		frank_rowand@mvista.com or source@mvista.com
22 *		debbie_chu@mvista.com
23 *    Copyright 2002-2004 MontaVista Software, Inc.
24 *	PowerPC 44x support, Matt Porter <mporter@kernel.crashing.org>
25 *    Copyright 2004 Freescale Semiconductor, Inc
26 *	PowerPC e500 modifications, Kumar Gala <galak@kernel.crashing.org>
27 */
28
29#include <linux/init.h>
30#include <linux/threads.h>
31#include <linux/pgtable.h>
32#include <linux/linkage.h>
33
34#include <asm/processor.h>
35#include <asm/page.h>
36#include <asm/mmu.h>
37#include <asm/cputable.h>
38#include <asm/thread_info.h>
39#include <asm/ppc_asm.h>
40#include <asm/asm-offsets.h>
41#include <asm/cache.h>
42#include <asm/ptrace.h>
43#include <asm/feature-fixups.h>
44#include "head_booke.h"
45
46/* As with the other PowerPC ports, it is expected that when code
47 * execution begins here, the following registers contain valid, yet
48 * optional, information:
49 *
50 *   r3 - Board info structure pointer (DRAM, frequency, MAC address, etc.)
51 *   r4 - Starting address of the init RAM disk
52 *   r5 - Ending address of the init RAM disk
53 *   r6 - Start of kernel command line string (e.g. "mem=128")
54 *   r7 - End of kernel command line string
55 *
56 */
57	__HEAD
58_GLOBAL(_stext);
59_GLOBAL(_start);
60	/*
61	 * Reserve a word at a fixed location to store the address
62	 * of abatron_pteptrs
63	 */
64	nop
65
66	/* Translate device tree address to physical, save in r30/r31 */
67	bl	get_phys_addr
68	mr	r30,r3
69	mr	r31,r4
70
71	li	r25,0			/* phys kernel start (low) */
72	li	r24,0			/* CPU number */
73	li	r23,0			/* phys kernel start (high) */
74
75#ifdef CONFIG_RELOCATABLE
76	LOAD_REG_ADDR_PIC(r3, _stext)	/* Get our current runtime base */
77
78	/* Translate _stext address to physical, save in r23/r25 */
79	bl	get_phys_addr
80	mr	r23,r3
81	mr	r25,r4
82
83	bcl	20,31,$+4
840:	mflr	r8
85	addis	r3,r8,(is_second_reloc - 0b)@ha
86	lwz	r19,(is_second_reloc - 0b)@l(r3)
87
88	/* Check if this is the second relocation. */
89	cmpwi	r19,1
90	bne	1f
91
92	/*
93	 * For the second relocation, we already get the real memstart_addr
94	 * from device tree. So we will map PAGE_OFFSET to memstart_addr,
95	 * then the virtual address of start kernel should be:
96	 *          PAGE_OFFSET + (kernstart_addr - memstart_addr)
97	 * Since the offset between kernstart_addr and memstart_addr should
98	 * never be beyond 1G, so we can just use the lower 32bit of them
99	 * for the calculation.
100	 */
101	lis	r3,PAGE_OFFSET@h
102
103	addis	r4,r8,(kernstart_addr - 0b)@ha
104	addi	r4,r4,(kernstart_addr - 0b)@l
105	lwz	r5,4(r4)
106
107	addis	r6,r8,(memstart_addr - 0b)@ha
108	addi	r6,r6,(memstart_addr - 0b)@l
109	lwz	r7,4(r6)
110
111	subf	r5,r7,r5
112	add	r3,r3,r5
113	b	2f
114
1151:
116	/*
117	 * We have the runtime (virtual) address of our base.
118	 * We calculate our shift of offset from a 64M page.
119	 * We could map the 64M page we belong to at PAGE_OFFSET and
120	 * get going from there.
121	 */
122	lis	r4,KERNELBASE@h
123	ori	r4,r4,KERNELBASE@l
124	rlwinm	r6,r25,0,0x3ffffff		/* r6 = PHYS_START % 64M */
125	rlwinm	r5,r4,0,0x3ffffff		/* r5 = KERNELBASE % 64M */
126	subf	r3,r5,r6			/* r3 = r6 - r5 */
127	add	r3,r4,r3			/* Required Virtual Address */
128
1292:	bl	relocate
130
131	/*
132	 * For the second relocation, we already set the right tlb entries
133	 * for the kernel space, so skip the code in 85xx_entry_mapping.S
134	*/
135	cmpwi	r19,1
136	beq	set_ivor
137#endif
138
139/* We try to not make any assumptions about how the boot loader
140 * setup or used the TLBs.  We invalidate all mappings from the
141 * boot loader and load a single entry in TLB1[0] to map the
142 * first 64M of kernel memory.  Any boot info passed from the
143 * bootloader needs to live in this first 64M.
144 *
145 * Requirement on bootloader:
146 *  - The page we're executing in needs to reside in TLB1 and
147 *    have IPROT=1.  If not an invalidate broadcast could
148 *    evict the entry we're currently executing in.
149 *
150 *  r3 = Index of TLB1 were executing in
151 *  r4 = Current MSR[IS]
152 *  r5 = Index of TLB1 temp mapping
153 *
154 * Later in mapin_ram we will correctly map lowmem, and resize TLB1[0]
155 * if needed
156 */
157
158_GLOBAL(__early_start)
159	LOAD_REG_ADDR_PIC(r20, kernstart_virt_addr)
160	lwz     r20,0(r20)
161
162#define ENTRY_MAPPING_BOOT_SETUP
163#include "85xx_entry_mapping.S"
164#undef ENTRY_MAPPING_BOOT_SETUP
165
166set_ivor:
167	/* Establish the interrupt vector offsets */
168	SET_IVOR(0,  CriticalInput);
169	SET_IVOR(1,  MachineCheck);
170	SET_IVOR(2,  DataStorage);
171	SET_IVOR(3,  InstructionStorage);
172	SET_IVOR(4,  ExternalInput);
173	SET_IVOR(5,  Alignment);
174	SET_IVOR(6,  Program);
175	SET_IVOR(7,  FloatingPointUnavailable);
176	SET_IVOR(8,  SystemCall);
177	SET_IVOR(9,  AuxillaryProcessorUnavailable);
178	SET_IVOR(10, Decrementer);
179	SET_IVOR(11, FixedIntervalTimer);
180	SET_IVOR(12, WatchdogTimer);
181	SET_IVOR(13, DataTLBError);
182	SET_IVOR(14, InstructionTLBError);
183	SET_IVOR(15, DebugCrit);
184
185	/* Establish the interrupt vector base */
186	lis	r4,interrupt_base@h	/* IVPR only uses the high 16-bits */
187	mtspr	SPRN_IVPR,r4
188
189	/* Setup the defaults for TLB entries */
190	li	r2,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
191	mtspr	SPRN_MAS4, r2
192
193#if !defined(CONFIG_BDI_SWITCH)
194	/*
195	 * The Abatron BDI JTAG debugger does not tolerate others
196	 * mucking with the debug registers.
197	 */
198	lis	r2,DBCR0_IDM@h
199	mtspr	SPRN_DBCR0,r2
200	isync
201	/* clear any residual debug events */
202	li	r2,-1
203	mtspr	SPRN_DBSR,r2
204#endif
205
206#ifdef CONFIG_SMP
207	/* Check to see if we're the second processor, and jump
208	 * to the secondary_start code if so
209	 */
210	LOAD_REG_ADDR_PIC(r24, boot_cpuid)
211	lwz	r24, 0(r24)
212	cmpwi	r24, -1
213	mfspr   r24,SPRN_PIR
214	bne	__secondary_start
215#endif
216
217	/*
218	 * This is where the main kernel code starts.
219	 */
220
221	/* ptr to current */
222	lis	r2,init_task@h
223	ori	r2,r2,init_task@l
224
225	/* ptr to current thread */
226	addi	r4,r2,THREAD	/* init task's THREAD */
227	mtspr	SPRN_SPRG_THREAD,r4
228
229	/* stack */
230	lis	r1,init_thread_union@h
231	ori	r1,r1,init_thread_union@l
232	li	r0,0
233	stwu	r0,THREAD_SIZE-STACK_FRAME_MIN_SIZE(r1)
234
235#ifdef CONFIG_SMP
236	stw	r24, TASK_CPU(r2)
237#endif
238
239	bl	early_init
240
241#ifdef CONFIG_KASAN
242	bl	kasan_early_init
243#endif
244#ifdef CONFIG_RELOCATABLE
245	mr	r3,r30
246	mr	r4,r31
247#ifdef CONFIG_PHYS_64BIT
248	mr	r5,r23
249	mr	r6,r25
250#else
251	mr	r5,r25
252#endif
253	bl	relocate_init
254#endif
255
256#ifdef CONFIG_DYNAMIC_MEMSTART
257	lis	r3,kernstart_addr@ha
258	la	r3,kernstart_addr@l(r3)
259#ifdef CONFIG_PHYS_64BIT
260	stw	r23,0(r3)
261	stw	r25,4(r3)
262#else
263	stw	r25,0(r3)
264#endif
265#endif
266
267/*
268 * Decide what sort of machine this is and initialize the MMU.
269 */
270	mr	r3,r30
271	mr	r4,r31
272	bl	machine_init
273	bl	MMU_init
274
275	/* Setup PTE pointers for the Abatron bdiGDB */
276	lis	r6, swapper_pg_dir@h
277	ori	r6, r6, swapper_pg_dir@l
278	lis	r5, abatron_pteptrs@h
279	ori	r5, r5, abatron_pteptrs@l
280	lis     r3, kernstart_virt_addr@ha
281	lwz     r4, kernstart_virt_addr@l(r3)
282	stw	r5, 0(r4)	/* Save abatron_pteptrs at a fixed location */
283	stw	r6, 0(r5)
284
285	/* Let's move on */
286	lis	r4,start_kernel@h
287	ori	r4,r4,start_kernel@l
288	lis	r3,MSR_KERNEL@h
289	ori	r3,r3,MSR_KERNEL@l
290	mtspr	SPRN_SRR0,r4
291	mtspr	SPRN_SRR1,r3
292	rfi			/* change context and jump to start_kernel */
293
294/* Macros to hide the PTE size differences
295 *
296 * FIND_PTE -- walks the page tables given EA & pgdir pointer
297 *   r10 -- free
298 *   r11 -- PGDIR pointer
299 *   r12 -- free
300 *   r13 -- EA of fault
301 *   label 2: is the bailout case
302 *
303 * if we find the pte (fall through):
304 *   r11 is low pte word
305 *   r12 is pointer to the pte
306 *   r10 is the pshift from the PGD, if we're a hugepage
307 */
308#ifdef CONFIG_PTE_64BIT
309#ifdef CONFIG_HUGETLB_PAGE
310#define FIND_PTE	\
311	rlwinm	r12, r13, 14, 18, 28;	/* Compute pgdir/pmd offset */	\
312	add	r12, r11, r12;						\
313	lwz	r11, 4(r12);		/* Get pgd/pmd entry */		\
314	rlwinm.	r10, r11, 32 - _PAGE_PSIZE_SHIFT, 0x1e; /* get tsize*/	\
315	bne	1000f;			/* Huge page (leaf entry) */	\
316	rlwinm.	r12, r11, 0, 0, 20;	/* Extract pt base address */	\
317	beq	2f;			/* Bail if no table */		\
318	rlwimi	r12, r13, 23, 20, 28;	/* Compute pte address */	\
319	li	r10, 0;			/* clear r10 */			\
320	lwz	r11, 4(r12);		/* Get pte entry */		\
3211000:
322#else
323#define FIND_PTE	\
324	rlwinm	r12, r13, 14, 18, 28;	/* Compute pgdir/pmd offset */	\
325	add	r12, r11, r12;						\
326	lwz	r11, 4(r12);		/* Get pgd/pmd entry */		\
327	rlwinm.	r12, r11, 0, 0, 20;	/* Extract pt base address */	\
328	beq	2f;			/* Bail if no table */		\
329	rlwimi	r12, r13, 23, 20, 28;	/* Compute pte address */	\
330	lwz	r11, 4(r12);		/* Get pte entry */
331#endif /* HUGEPAGE */
332#else /* !PTE_64BIT */
333#define FIND_PTE	\
334	rlwimi	r11, r13, 12, 20, 29;	/* Create L1 (pgdir/pmd) address */	\
335	lwz	r11, 0(r11);		/* Get L1 entry */			\
336	rlwinm.	r12, r11, 0, 0, 19;	/* Extract L2 (pte) base address */	\
337	beq	2f;			/* Bail if no table */			\
338	rlwimi	r12, r13, 22, 20, 29;	/* Compute PTE address */		\
339	lwz	r11, 0(r12);		/* Get Linux PTE */
340#endif
341
342/*
343 * Interrupt vector entry code
344 *
345 * The Book E MMUs are always on so we don't need to handle
346 * interrupts in real mode as with previous PPC processors. In
347 * this case we handle interrupts in the kernel virtual address
348 * space.
349 *
350 * Interrupt vectors are dynamically placed relative to the
351 * interrupt prefix as determined by the address of interrupt_base.
352 * The interrupt vectors offsets are programmed using the labels
353 * for each interrupt vector entry.
354 *
355 * Interrupt vectors must be aligned on a 16 byte boundary.
356 * We align on a 32 byte cache line boundary for good measure.
357 */
358
359interrupt_base:
360	/* Critical Input Interrupt */
361	CRITICAL_EXCEPTION(0x0100, CRITICAL, CriticalInput, unknown_exception)
362
363	/* Machine Check Interrupt */
364	MCHECK_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
365
366	/* Data Storage Interrupt */
367	START_EXCEPTION(DataStorage)
368	NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE)
369	mfspr	r5,SPRN_ESR		/* Grab the ESR, save it */
370	stw	r5,_ESR(r11)
371	mfspr	r4,SPRN_DEAR		/* Grab the DEAR, save it */
372	stw	r4, _DEAR(r11)
373	andis.	r10,r5,(ESR_ILK|ESR_DLK)@h
374	bne	1f
375	prepare_transfer_to_handler
376	bl	do_page_fault
377	b	interrupt_return
3781:
379	prepare_transfer_to_handler
380	bl	CacheLockingException
381	b	interrupt_return
382
383	/* Instruction Storage Interrupt */
384	INSTRUCTION_STORAGE_EXCEPTION
385
386	/* External Input Interrupt */
387	EXCEPTION(0x0500, EXTERNAL, ExternalInput, do_IRQ)
388
389	/* Alignment Interrupt */
390	ALIGNMENT_EXCEPTION
391
392	/* Program Interrupt */
393	PROGRAM_EXCEPTION
394
395	/* Floating Point Unavailable Interrupt */
396#ifdef CONFIG_PPC_FPU
397	FP_UNAVAILABLE_EXCEPTION
398#else
399	EXCEPTION(0x0800, FP_UNAVAIL, FloatingPointUnavailable, emulation_assist_interrupt)
400#endif
401
402	/* System Call Interrupt */
403	START_EXCEPTION(SystemCall)
404	SYSCALL_ENTRY   0xc00 BOOKE_INTERRUPT_SYSCALL SPRN_SRR1
405
406	/* Auxiliary Processor Unavailable Interrupt */
407	EXCEPTION(0x2900, AP_UNAVAIL, AuxillaryProcessorUnavailable, unknown_exception)
408
409	/* Decrementer Interrupt */
410	DECREMENTER_EXCEPTION
411
412	/* Fixed Internal Timer Interrupt */
413	/* TODO: Add FIT support */
414	EXCEPTION(0x3100, FIT, FixedIntervalTimer, unknown_exception)
415
416	/* Watchdog Timer Interrupt */
417#ifdef CONFIG_BOOKE_WDT
418	CRITICAL_EXCEPTION(0x3200, WATCHDOG, WatchdogTimer, WatchdogException)
419#else
420	CRITICAL_EXCEPTION(0x3200, WATCHDOG, WatchdogTimer, unknown_exception)
421#endif
422
423	/* Data TLB Error Interrupt */
424	START_EXCEPTION(DataTLBError)
425	mtspr	SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
426	mfspr	r10, SPRN_SPRG_THREAD
427	stw	r11, THREAD_NORMSAVE(0)(r10)
428#ifdef CONFIG_KVM_BOOKE_HV
429BEGIN_FTR_SECTION
430	mfspr	r11, SPRN_SRR1
431END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
432#endif
433	stw	r12, THREAD_NORMSAVE(1)(r10)
434	stw	r13, THREAD_NORMSAVE(2)(r10)
435	mfcr	r13
436	stw	r13, THREAD_NORMSAVE(3)(r10)
437	DO_KVM	BOOKE_INTERRUPT_DTLB_MISS SPRN_SRR1
438START_BTB_FLUSH_SECTION
439	mfspr r11, SPRN_SRR1
440	andi. r10,r11,MSR_PR
441	beq 1f
442	BTB_FLUSH(r10)
4431:
444END_BTB_FLUSH_SECTION
445	mfspr	r13, SPRN_DEAR		/* Get faulting address */
446
447	/* If we are faulting a kernel address, we have to use the
448	 * kernel page tables.
449	 */
450	lis	r11, PAGE_OFFSET@h
451	cmplw	5, r13, r11
452	blt	5, 3f
453	lis	r11, swapper_pg_dir@h
454	ori	r11, r11, swapper_pg_dir@l
455
456	mfspr	r12,SPRN_MAS1		/* Set TID to 0 */
457	rlwinm	r12,r12,0,16,1
458	mtspr	SPRN_MAS1,r12
459
460	b	4f
461
462	/* Get the PGD for the current thread */
4633:
464	mfspr	r11,SPRN_SPRG_THREAD
465	lwz	r11,PGDIR(r11)
466
467#ifdef CONFIG_PPC_KUAP
468	mfspr	r12, SPRN_MAS1
469	rlwinm.	r12,r12,0,0x3fff0000
470	beq	2f			/* KUAP fault */
471#endif
472
4734:
474	FIND_PTE
475
476#ifdef CONFIG_PTE_64BIT
477	li	r13,_PAGE_PRESENT|_PAGE_BAP_SR
478	oris	r13,r13,_PAGE_ACCESSED@h
479#else
480	li	r13,_PAGE_PRESENT|_PAGE_READ|_PAGE_ACCESSED
481#endif
482	andc.	r13,r13,r11		/* Check permission */
483
484#ifdef CONFIG_PTE_64BIT
485#ifdef CONFIG_SMP
486	subf	r13,r11,r12		/* create false data dep */
487	lwzx	r13,r11,r13		/* Get upper pte bits */
488#else
489	lwz	r13,0(r12)		/* Get upper pte bits */
490#endif
491#endif
492
493	bne	2f			/* Bail if permission/valid mismatch */
494
495	/* Jump to common tlb load */
496	b	finish_tlb_load
4972:
498	/* The bailout.  Restore registers to pre-exception conditions
499	 * and call the heavyweights to help us out.
500	 */
501	mfspr	r10, SPRN_SPRG_THREAD
502	lwz	r11, THREAD_NORMSAVE(3)(r10)
503	mtcr	r11
504	lwz	r13, THREAD_NORMSAVE(2)(r10)
505	lwz	r12, THREAD_NORMSAVE(1)(r10)
506	lwz	r11, THREAD_NORMSAVE(0)(r10)
507	mfspr	r10, SPRN_SPRG_RSCRATCH0
508	b	DataStorage
509
510	/* Instruction TLB Error Interrupt */
511	/*
512	 * Nearly the same as above, except we get our
513	 * information from different registers and bailout
514	 * to a different point.
515	 */
516	START_EXCEPTION(InstructionTLBError)
517	mtspr	SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
518	mfspr	r10, SPRN_SPRG_THREAD
519	stw	r11, THREAD_NORMSAVE(0)(r10)
520#ifdef CONFIG_KVM_BOOKE_HV
521BEGIN_FTR_SECTION
522	mfspr	r11, SPRN_SRR1
523END_FTR_SECTION_IFSET(CPU_FTR_EMB_HV)
524#endif
525	stw	r12, THREAD_NORMSAVE(1)(r10)
526	stw	r13, THREAD_NORMSAVE(2)(r10)
527	mfcr	r13
528	stw	r13, THREAD_NORMSAVE(3)(r10)
529	DO_KVM	BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR1
530START_BTB_FLUSH_SECTION
531	mfspr r11, SPRN_SRR1
532	andi. r10,r11,MSR_PR
533	beq 1f
534	BTB_FLUSH(r10)
5351:
536END_BTB_FLUSH_SECTION
537
538	mfspr	r13, SPRN_SRR0		/* Get faulting address */
539
540	/* If we are faulting a kernel address, we have to use the
541	 * kernel page tables.
542	 */
543	lis	r11, PAGE_OFFSET@h
544	cmplw	5, r13, r11
545	blt	5, 3f
546	lis	r11, swapper_pg_dir@h
547	ori	r11, r11, swapper_pg_dir@l
548
549	mfspr	r12,SPRN_MAS1		/* Set TID to 0 */
550	rlwinm	r12,r12,0,16,1
551	mtspr	SPRN_MAS1,r12
552
553	FIND_PTE
554	/* Make up the required permissions for kernel code */
555#ifdef CONFIG_PTE_64BIT
556	li	r13,_PAGE_PRESENT | _PAGE_BAP_SX
557	oris	r13,r13,_PAGE_ACCESSED@h
558#else
559	li	r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
560#endif
561	b	4f
562
563	/* Get the PGD for the current thread */
5643:
565	mfspr	r11,SPRN_SPRG_THREAD
566	lwz	r11,PGDIR(r11)
567
568#ifdef CONFIG_PPC_KUAP
569	mfspr	r12, SPRN_MAS1
570	rlwinm.	r12,r12,0,0x3fff0000
571	beq	2f			/* KUAP fault */
572#endif
573
574	FIND_PTE
575	/* Make up the required permissions for user code */
576#ifdef CONFIG_PTE_64BIT
577	li	r13,_PAGE_PRESENT | _PAGE_BAP_UX
578	oris	r13,r13,_PAGE_ACCESSED@h
579#else
580	li	r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
581#endif
582
5834:
584	andc.	r13,r13,r11		/* Check permission */
585
586#ifdef CONFIG_PTE_64BIT
587#ifdef CONFIG_SMP
588	subf	r13,r11,r12		/* create false data dep */
589	lwzx	r13,r11,r13		/* Get upper pte bits */
590#else
591	lwz	r13,0(r12)		/* Get upper pte bits */
592#endif
593#endif
594
595	bne	2f			/* Bail if permission mismatch */
596
597	/* Jump to common TLB load point */
598	b	finish_tlb_load
599
6002:
601	/* The bailout.  Restore registers to pre-exception conditions
602	 * and call the heavyweights to help us out.
603	 */
604	mfspr	r10, SPRN_SPRG_THREAD
605	lwz	r11, THREAD_NORMSAVE(3)(r10)
606	mtcr	r11
607	lwz	r13, THREAD_NORMSAVE(2)(r10)
608	lwz	r12, THREAD_NORMSAVE(1)(r10)
609	lwz	r11, THREAD_NORMSAVE(0)(r10)
610	mfspr	r10, SPRN_SPRG_RSCRATCH0
611	b	InstructionStorage
612
613/* Define SPE handlers for e500v2 */
614#ifdef CONFIG_SPE
615	/* SPE Unavailable */
616	START_EXCEPTION(SPEUnavailable)
617	NORMAL_EXCEPTION_PROLOG(0x2010, SPE_UNAVAIL)
618	beq	1f
619	bl	load_up_spe
620	b	fast_exception_return
6211:	prepare_transfer_to_handler
622	bl	KernelSPE
623	b	interrupt_return
624#elif defined(CONFIG_SPE_POSSIBLE)
625	EXCEPTION(0x2020, SPE_UNAVAIL, SPEUnavailable, unknown_exception)
626#endif /* CONFIG_SPE_POSSIBLE */
627
628	/* SPE Floating Point Data */
629#ifdef CONFIG_SPE
630	START_EXCEPTION(SPEFloatingPointData)
631	NORMAL_EXCEPTION_PROLOG(0x2030, SPE_FP_DATA)
632	prepare_transfer_to_handler
633	bl	SPEFloatingPointException
634	REST_NVGPRS(r1)
635	b	interrupt_return
636
637	/* SPE Floating Point Round */
638	START_EXCEPTION(SPEFloatingPointRound)
639	NORMAL_EXCEPTION_PROLOG(0x2050, SPE_FP_ROUND)
640	prepare_transfer_to_handler
641	bl	SPEFloatingPointRoundException
642	REST_NVGPRS(r1)
643	b	interrupt_return
644#elif defined(CONFIG_SPE_POSSIBLE)
645	EXCEPTION(0x2040, SPE_FP_DATA, SPEFloatingPointData, unknown_exception)
646	EXCEPTION(0x2050, SPE_FP_ROUND, SPEFloatingPointRound, unknown_exception)
647#endif /* CONFIG_SPE_POSSIBLE */
648
649
650	/* Performance Monitor */
651	EXCEPTION(0x2060, PERFORMANCE_MONITOR, PerformanceMonitor, \
652		  performance_monitor_exception)
653
654	EXCEPTION(0x2070, DOORBELL, Doorbell, doorbell_exception)
655
656	CRITICAL_EXCEPTION(0x2080, DOORBELL_CRITICAL, \
657			   CriticalDoorbell, unknown_exception)
658
659	/* Debug Interrupt */
660	DEBUG_DEBUG_EXCEPTION
661	DEBUG_CRIT_EXCEPTION
662
663	GUEST_DOORBELL_EXCEPTION
664
665	CRITICAL_EXCEPTION(0, GUEST_DBELL_CRIT, CriticalGuestDoorbell, \
666			   unknown_exception)
667
668	/* Hypercall */
669	EXCEPTION(0, HV_SYSCALL, Hypercall, unknown_exception)
670
671	/* Embedded Hypervisor Privilege */
672	EXCEPTION(0, HV_PRIV, Ehvpriv, unknown_exception)
673
674interrupt_end:
675
676/*
677 * Local functions
678 */
679
680/*
681 * Both the instruction and data TLB miss get to this
682 * point to load the TLB.
683 *	r10 - tsize encoding (if HUGETLB_PAGE) or available to use
684 *	r11 - TLB (info from Linux PTE)
685 *	r12 - available to use
686 *	r13 - upper bits of PTE (if PTE_64BIT) or available to use
687 *	CR5 - results of addr >= PAGE_OFFSET
688 *	MAS0, MAS1 - loaded with proper value when we get here
689 *	MAS2, MAS3 - will need additional info from Linux PTE
690 *	Upon exit, we reload everything and RFI.
691 */
692finish_tlb_load:
693#ifdef CONFIG_HUGETLB_PAGE
694	cmpwi	6, r10, 0			/* check for huge page */
695	beq	6, finish_tlb_load_cont    	/* !huge */
696
697	/* Alas, we need more scratch registers for hugepages */
698	mfspr	r12, SPRN_SPRG_THREAD
699	stw	r14, THREAD_NORMSAVE(4)(r12)
700	stw	r15, THREAD_NORMSAVE(5)(r12)
701	stw	r16, THREAD_NORMSAVE(6)(r12)
702	stw	r17, THREAD_NORMSAVE(7)(r12)
703
704	/* Get the next_tlbcam_idx percpu var */
705#ifdef CONFIG_SMP
706	lwz	r15, TASK_CPU-THREAD(r12)
707	lis     r14, __per_cpu_offset@h
708	ori     r14, r14, __per_cpu_offset@l
709	rlwinm  r15, r15, 2, 0, 29
710	lwzx    r16, r14, r15
711#else
712	li	r16, 0
713#endif
714	lis     r17, next_tlbcam_idx@h
715	ori	r17, r17, next_tlbcam_idx@l
716	add	r17, r17, r16			/* r17 = *next_tlbcam_idx */
717	lwz     r15, 0(r17)			/* r15 = next_tlbcam_idx */
718
719	lis	r14, MAS0_TLBSEL(1)@h		/* select TLB1 (TLBCAM) */
720	rlwimi	r14, r15, 16, 4, 15		/* next_tlbcam_idx entry */
721	mtspr	SPRN_MAS0, r14
722
723	/* Extract TLB1CFG(NENTRY) */
724	mfspr	r16, SPRN_TLB1CFG
725	andi.	r16, r16, 0xfff
726
727	/* Update next_tlbcam_idx, wrapping when necessary */
728	addi	r15, r15, 1
729	cmpw	r15, r16
730	blt 	100f
731	lis	r14, tlbcam_index@h
732	ori	r14, r14, tlbcam_index@l
733	lwz	r15, 0(r14)
734100:	stw	r15, 0(r17)
735
736	mfspr	r16, SPRN_MAS1
737	rlwimi	r16, r10, MAS1_TSIZE_SHIFT, MAS1_TSIZE_MASK
738	mtspr	SPRN_MAS1, r16
739
740	/* copy the pshift for use later */
741	addi	r14, r10, _PAGE_PSIZE_SHIFT_OFFSET
742
743	/* fall through */
744
745#endif /* CONFIG_HUGETLB_PAGE */
746
747	/*
748	 * We set execute, because we don't have the granularity to
749	 * properly set this at the page level (Linux problem).
750	 * Many of these bits are software only.  Bits we don't set
751	 * here we (properly should) assume have the appropriate value.
752	 */
753finish_tlb_load_cont:
754#ifdef CONFIG_PTE_64BIT
755	rlwinm	r12, r11, 32-2, 26, 31	/* Move in perm bits */
756	andi.	r10, r11, _PAGE_DIRTY
757	bne	1f
758	li	r10, MAS3_SW | MAS3_UW
759	andc	r12, r12, r10
7601:	rlwimi	r12, r13, 20, 0, 11	/* grab RPN[32:43] */
761	rlwimi	r12, r11, 20, 12, 19	/* grab RPN[44:51] */
7622:	mtspr	SPRN_MAS3, r12
763BEGIN_MMU_FTR_SECTION
764	srwi	r10, r13, 12		/* grab RPN[12:31] */
765	mtspr	SPRN_MAS7, r10
766END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
767#else
768	li	r10, (_PAGE_EXEC | _PAGE_READ)
769	mr	r13, r11
770	rlwimi	r10, r11, 31, 29, 29	/* extract _PAGE_DIRTY into SW */
771	and	r12, r11, r10
772	mcrf	cr0, cr5		/* Test for user page */
773	slwi	r10, r12, 1
774	or	r10, r10, r12
775	rlwinm	r10, r10, 0, ~_PAGE_EXEC	/* Clear SX on user pages */
776	isellt	r12, r10, r12
777	rlwimi	r13, r12, 0, 20, 31	/* Get RPN from PTE, merge w/ perms */
778	mtspr	SPRN_MAS3, r13
779#endif
780
781	mfspr	r12, SPRN_MAS2
782#ifdef CONFIG_PTE_64BIT
783	rlwimi	r12, r11, 32-19, 27, 31	/* extract WIMGE from pte */
784#else
785	rlwimi	r12, r11, 26, 27, 31	/* extract WIMGE from pte */
786#endif
787#ifdef CONFIG_HUGETLB_PAGE
788	beq	6, 3f			/* don't mask if page isn't huge */
789	li	r13, 1
790	slw	r13, r13, r14
791	subi	r13, r13, 1
792	rlwinm	r13, r13, 0, 0, 19	/* bottom bits used for WIMGE/etc */
793	andc	r12, r12, r13		/* mask off ea bits within the page */
794#endif
7953:	mtspr	SPRN_MAS2, r12
796
797tlb_write_entry:
798	tlbwe
799
800	/* Done...restore registers and get out of here.  */
801	mfspr	r10, SPRN_SPRG_THREAD
802#ifdef CONFIG_HUGETLB_PAGE
803	beq	6, 8f /* skip restore for 4k page faults */
804	lwz	r14, THREAD_NORMSAVE(4)(r10)
805	lwz	r15, THREAD_NORMSAVE(5)(r10)
806	lwz	r16, THREAD_NORMSAVE(6)(r10)
807	lwz	r17, THREAD_NORMSAVE(7)(r10)
808#endif
8098:	lwz	r11, THREAD_NORMSAVE(3)(r10)
810	mtcr	r11
811	lwz	r13, THREAD_NORMSAVE(2)(r10)
812	lwz	r12, THREAD_NORMSAVE(1)(r10)
813	lwz	r11, THREAD_NORMSAVE(0)(r10)
814	mfspr	r10, SPRN_SPRG_RSCRATCH0
815	rfi					/* Force context change */
816
817#ifdef CONFIG_SPE
818/* Note that the SPE support is closely modeled after the AltiVec
819 * support.  Changes to one are likely to be applicable to the
820 * other!  */
821_GLOBAL(load_up_spe)
822/*
823 * Disable SPE for the task which had SPE previously,
824 * and save its SPE registers in its thread_struct.
825 * Enables SPE for use in the kernel on return.
826 * On SMP we know the SPE units are free, since we give it up every
827 * switch.  -- Kumar
828 */
829	mfmsr	r5
830	oris	r5,r5,MSR_SPE@h
831	mtmsr	r5			/* enable use of SPE now */
832	isync
833	/* enable use of SPE after return */
834	oris	r9,r9,MSR_SPE@h
835	mfspr	r5,SPRN_SPRG_THREAD	/* current task's THREAD (phys) */
836	li	r4,1
837	li	r10,THREAD_ACC
838	stw	r4,THREAD_USED_SPE(r5)
839	evlddx	evr4,r10,r5
840	evmra	evr4,evr4
841	REST_32EVRS(0,r10,r5,THREAD_EVR0)
842	blr
843
844/*
845 * SPE unavailable trap from kernel - print a message, but let
846 * the task use SPE in the kernel until it returns to user mode.
847 */
848SYM_FUNC_START_LOCAL(KernelSPE)
849	lwz	r3,_MSR(r1)
850	oris	r3,r3,MSR_SPE@h
851	stw	r3,_MSR(r1)	/* enable use of SPE after return */
852#ifdef CONFIG_PRINTK
853	lis	r3,87f@h
854	ori	r3,r3,87f@l
855	mr	r4,r2		/* current */
856	lwz	r5,_NIP(r1)
857	bl	_printk
858#endif
859	b	interrupt_return
860#ifdef CONFIG_PRINTK
86187:	.string	"SPE used in kernel  (task=%p, pc=%x)  \n"
862#endif
863	.align	4,0
864
865SYM_FUNC_END(KernelSPE)
866#endif /* CONFIG_SPE */
867
868/*
869 * Translate the effec addr in r3 to phys addr. The phys addr will be put
870 * into r3(higher 32bit) and r4(lower 32bit)
871 */
872SYM_FUNC_START_LOCAL(get_phys_addr)
873	mfmsr	r8
874	mfspr	r9,SPRN_PID
875	rlwinm	r9,r9,16,0x3fff0000	/* turn PID into MAS6[SPID] */
876	rlwimi	r9,r8,28,0x00000001	/* turn MSR[DS] into MAS6[SAS] */
877	mtspr	SPRN_MAS6,r9
878
879	tlbsx	0,r3			/* must succeed */
880
881	mfspr	r8,SPRN_MAS1
882	mfspr	r12,SPRN_MAS3
883	rlwinm	r9,r8,25,0x1f		/* r9 = log2(page size) */
884	li	r10,1024
885	slw	r10,r10,r9		/* r10 = page size */
886	addi	r10,r10,-1
887	and	r11,r3,r10		/* r11 = page offset */
888	andc	r4,r12,r10		/* r4 = page base */
889	or	r4,r4,r11		/* r4 = devtree phys addr */
890#ifdef CONFIG_PHYS_64BIT
891	mfspr	r3,SPRN_MAS7
892#endif
893	blr
894SYM_FUNC_END(get_phys_addr)
895
896/*
897 * Global functions
898 */
899
900#ifdef CONFIG_PPC_E500
901#ifndef CONFIG_PPC_E500MC
902/* Adjust or setup IVORs for e500v1/v2 */
903_GLOBAL(__setup_e500_ivors)
904	li	r3,DebugCrit@l
905	mtspr	SPRN_IVOR15,r3
906	li	r3,SPEUnavailable@l
907	mtspr	SPRN_IVOR32,r3
908	li	r3,SPEFloatingPointData@l
909	mtspr	SPRN_IVOR33,r3
910	li	r3,SPEFloatingPointRound@l
911	mtspr	SPRN_IVOR34,r3
912	li	r3,PerformanceMonitor@l
913	mtspr	SPRN_IVOR35,r3
914	sync
915	blr
916#else
917/* Adjust or setup IVORs for e500mc */
918_GLOBAL(__setup_e500mc_ivors)
919	li	r3,DebugDebug@l
920	mtspr	SPRN_IVOR15,r3
921	li	r3,PerformanceMonitor@l
922	mtspr	SPRN_IVOR35,r3
923	li	r3,Doorbell@l
924	mtspr	SPRN_IVOR36,r3
925	li	r3,CriticalDoorbell@l
926	mtspr	SPRN_IVOR37,r3
927	sync
928	blr
929
930/* setup ehv ivors for */
931_GLOBAL(__setup_ehv_ivors)
932	li	r3,GuestDoorbell@l
933	mtspr	SPRN_IVOR38,r3
934	li	r3,CriticalGuestDoorbell@l
935	mtspr	SPRN_IVOR39,r3
936	li	r3,Hypercall@l
937	mtspr	SPRN_IVOR40,r3
938	li	r3,Ehvpriv@l
939	mtspr	SPRN_IVOR41,r3
940	sync
941	blr
942#endif /* CONFIG_PPC_E500MC */
943#endif /* CONFIG_PPC_E500 */
944
945#ifdef CONFIG_SPE
946/*
947 * extern void __giveup_spe(struct task_struct *prev)
948 *
949 */
950_GLOBAL(__giveup_spe)
951	addi	r3,r3,THREAD		/* want THREAD of task */
952	lwz	r5,PT_REGS(r3)
953	cmpi	0,r5,0
954	SAVE_32EVRS(0, r4, r3, THREAD_EVR0)
955	evxor	evr6, evr6, evr6	/* clear out evr6 */
956	evmwumiaa evr6, evr6, evr6	/* evr6 <- ACC = 0 * 0 + ACC */
957	li	r4,THREAD_ACC
958	evstddx	evr6, r4, r3		/* save off accumulator */
959	beq	1f
960	lwz	r4,_MSR-STACK_INT_FRAME_REGS(r5)
961	lis	r3,MSR_SPE@h
962	andc	r4,r4,r3		/* disable SPE for previous task */
963	stw	r4,_MSR-STACK_INT_FRAME_REGS(r5)
9641:
965	blr
966#endif /* CONFIG_SPE */
967
968/*
969 * extern void abort(void)
970 *
971 * At present, this routine just applies a system reset.
972 */
973_GLOBAL(abort)
974	li	r13,0
975	mtspr	SPRN_DBCR0,r13		/* disable all debug events */
976	isync
977	mfmsr	r13
978	ori	r13,r13,MSR_DE@l	/* Enable Debug Events */
979	mtmsr	r13
980	isync
981	mfspr	r13,SPRN_DBCR0
982	lis	r13,(DBCR0_IDM|DBCR0_RST_CHIP)@h
983	mtspr	SPRN_DBCR0,r13
984	isync
985
986#ifdef CONFIG_SMP
987/* When we get here, r24 needs to hold the CPU # */
988	.globl __secondary_start
989__secondary_start:
990	LOAD_REG_ADDR_PIC(r3, tlbcam_index)
991	lwz	r3,0(r3)
992	mtctr	r3
993	li	r26,0		/* r26 safe? */
994
995	bl	switch_to_as1
996	mr	r27,r3		/* tlb entry */
997	/* Load each CAM entry */
9981:	mr	r3,r26
999	bl	loadcam_entry
1000	addi	r26,r26,1
1001	bdnz	1b
1002	mr	r3,r27		/* tlb entry */
1003	LOAD_REG_ADDR_PIC(r4, memstart_addr)
1004	lwz	r4,0(r4)
1005	mr	r5,r25		/* phys kernel start */
1006	rlwinm	r5,r5,0,~0x3ffffff	/* aligned 64M */
1007	subf	r4,r5,r4	/* memstart_addr - phys kernel start */
1008	lis	r7,KERNELBASE@h
1009	ori	r7,r7,KERNELBASE@l
1010	cmpw	r20,r7		/* if kernstart_virt_addr != KERNELBASE, randomized */
1011	beq	2f
1012	li	r4,0
10132:	li	r5,0		/* no device tree */
1014	li	r6,0		/* not boot cpu */
1015	bl	restore_to_as0
1016
1017
1018	lis	r3,__secondary_hold_acknowledge@h
1019	ori	r3,r3,__secondary_hold_acknowledge@l
1020	stw	r24,0(r3)
1021
1022	li	r3,0
1023	mr	r4,r24		/* Why? */
1024	bl	call_setup_cpu
1025
1026	/* get current's stack and current */
1027	lis	r2,secondary_current@ha
1028	lwz	r2,secondary_current@l(r2)
1029	lwz	r1,TASK_STACK(r2)
1030
1031	/* stack */
1032	addi	r1,r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE
1033	li	r0,0
1034	stw	r0,0(r1)
1035
1036	/* ptr to current thread */
1037	addi	r4,r2,THREAD	/* address of our thread_struct */
1038	mtspr	SPRN_SPRG_THREAD,r4
1039
1040	/* Setup the defaults for TLB entries */
1041	li	r4,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
1042	mtspr	SPRN_MAS4,r4
1043
1044	/* Jump to start_secondary */
1045	lis	r4,MSR_KERNEL@h
1046	ori	r4,r4,MSR_KERNEL@l
1047	lis	r3,start_secondary@h
1048	ori	r3,r3,start_secondary@l
1049	mtspr	SPRN_SRR0,r3
1050	mtspr	SPRN_SRR1,r4
1051	sync
1052	rfi
1053	sync
1054
1055	.globl __secondary_hold_acknowledge
1056__secondary_hold_acknowledge:
1057	.long	-1
1058#endif
1059
1060/*
1061 * Create a 64M tlb by address and entry
1062 * r3 - entry
1063 * r4 - virtual address
1064 * r5/r6 - physical address
1065 */
1066_GLOBAL(create_kaslr_tlb_entry)
1067	lis     r7,0x1000               /* Set MAS0(TLBSEL) = 1 */
1068	rlwimi  r7,r3,16,4,15           /* Setup MAS0 = TLBSEL | ESEL(r6) */
1069	mtspr   SPRN_MAS0,r7            /* Write MAS0 */
1070
1071	lis     r3,(MAS1_VALID|MAS1_IPROT)@h
1072	ori     r3,r3,(MAS1_TSIZE(BOOK3E_PAGESZ_64M))@l
1073	mtspr   SPRN_MAS1,r3            /* Write MAS1 */
1074
1075	lis     r3,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@h
1076	ori     r3,r3,MAS2_EPN_MASK(BOOK3E_PAGESZ_64M)@l
1077	and     r3,r3,r4
1078	ori	r3,r3,MAS2_M_IF_NEEDED@l
1079	mtspr   SPRN_MAS2,r3            /* Write MAS2(EPN) */
1080
1081#ifdef CONFIG_PHYS_64BIT
1082	ori     r8,r6,(MAS3_SW|MAS3_SR|MAS3_SX)
1083	mtspr   SPRN_MAS3,r8            /* Write MAS3(RPN) */
1084	mtspr	SPRN_MAS7,r5
1085#else
1086	ori     r8,r5,(MAS3_SW|MAS3_SR|MAS3_SX)
1087	mtspr   SPRN_MAS3,r8            /* Write MAS3(RPN) */
1088#endif
1089
1090	tlbwe                           /* Write TLB */
1091	isync
1092	sync
1093	blr
1094
1095/*
1096 * Return to the start of the relocated kernel and run again
1097 * r3 - virtual address of fdt
1098 * r4 - entry of the kernel
1099 */
1100_GLOBAL(reloc_kernel_entry)
1101	mfmsr	r7
1102	rlwinm	r7, r7, 0, ~(MSR_IS | MSR_DS)
1103
1104	mtspr	SPRN_SRR0,r4
1105	mtspr	SPRN_SRR1,r7
1106	rfi
1107
1108/*
1109 * Create a tlb entry with the same effective and physical address as
1110 * the tlb entry used by the current running code. But set the TS to 1.
1111 * Then switch to the address space 1. It will return with the r3 set to
1112 * the ESEL of the new created tlb.
1113 */
1114_GLOBAL(switch_to_as1)
1115	mflr	r5
1116
1117	/* Find a entry not used */
1118	mfspr	r3,SPRN_TLB1CFG
1119	andi.	r3,r3,0xfff
1120	mfspr	r4,SPRN_PID
1121	rlwinm	r4,r4,16,0x3fff0000	/* turn PID into MAS6[SPID] */
1122	mtspr	SPRN_MAS6,r4
11231:	lis	r4,0x1000		/* Set MAS0(TLBSEL) = 1 */
1124	addi	r3,r3,-1
1125	rlwimi	r4,r3,16,4,15		/* Setup MAS0 = TLBSEL | ESEL(r3) */
1126	mtspr	SPRN_MAS0,r4
1127	tlbre
1128	mfspr	r4,SPRN_MAS1
1129	andis.	r4,r4,MAS1_VALID@h
1130	bne	1b
1131
1132	/* Get the tlb entry used by the current running code */
1133	bcl	20,31,$+4
11340:	mflr	r4
1135	tlbsx	0,r4
1136
1137	mfspr	r4,SPRN_MAS1
1138	ori	r4,r4,MAS1_TS		/* Set the TS = 1 */
1139	mtspr	SPRN_MAS1,r4
1140
1141	mfspr	r4,SPRN_MAS0
1142	rlwinm	r4,r4,0,~MAS0_ESEL_MASK
1143	rlwimi	r4,r3,16,4,15		/* Setup MAS0 = TLBSEL | ESEL(r3) */
1144	mtspr	SPRN_MAS0,r4
1145	tlbwe
1146	isync
1147	sync
1148
1149	mfmsr	r4
1150	ori	r4,r4,MSR_IS | MSR_DS
1151	mtspr	SPRN_SRR0,r5
1152	mtspr	SPRN_SRR1,r4
1153	sync
1154	rfi
1155
1156/*
1157 * Restore to the address space 0 and also invalidate the tlb entry created
1158 * by switch_to_as1.
1159 * r3 - the tlb entry which should be invalidated
1160 * r4 - __pa(PAGE_OFFSET in AS1) - __pa(PAGE_OFFSET in AS0)
1161 * r5 - device tree virtual address. If r4 is 0, r5 is ignored.
1162 * r6 - boot cpu
1163*/
1164_GLOBAL(restore_to_as0)
1165	mflr	r0
1166
1167	bcl	20,31,$+4
11680:	mflr	r9
1169	addi	r9,r9,1f - 0b
1170
1171	/*
1172	 * We may map the PAGE_OFFSET in AS0 to a different physical address,
1173	 * so we need calculate the right jump and device tree address based
1174	 * on the offset passed by r4.
1175	 */
1176	add	r9,r9,r4
1177	add	r5,r5,r4
1178	add	r0,r0,r4
1179
11802:	mfmsr	r7
1181	li	r8,(MSR_IS | MSR_DS)
1182	andc	r7,r7,r8
1183
1184	mtspr	SPRN_SRR0,r9
1185	mtspr	SPRN_SRR1,r7
1186	sync
1187	rfi
1188
1189	/* Invalidate the temporary tlb entry for AS1 */
11901:	lis	r9,0x1000		/* Set MAS0(TLBSEL) = 1 */
1191	rlwimi	r9,r3,16,4,15		/* Setup MAS0 = TLBSEL | ESEL(r3) */
1192	mtspr	SPRN_MAS0,r9
1193	tlbre
1194	mfspr	r9,SPRN_MAS1
1195	rlwinm	r9,r9,0,2,31		/* Clear MAS1 Valid and IPPROT */
1196	mtspr	SPRN_MAS1,r9
1197	tlbwe
1198	isync
1199
1200	cmpwi	r4,0
1201	cmpwi	cr1,r6,0
1202	cror	eq,4*cr1+eq,eq
1203	bne	3f			/* offset != 0 && is_boot_cpu */
1204	mtlr	r0
1205	blr
1206
1207	/*
1208	 * The PAGE_OFFSET will map to a different physical address,
1209	 * jump to _start to do another relocation again.
1210	*/
12113:	mr	r3,r5
1212	bl	_start
1213