xref: /openbmc/linux/arch/powerpc/kernel/misc_32.S (revision 7dd65feb)
1/*
2 * This file contains miscellaneous low-level functions.
3 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 *
5 * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
6 * and Paul Mackerras.
7 *
8 * kexec bits:
9 * Copyright (C) 2002-2003 Eric Biederman  <ebiederm@xmission.com>
10 * GameCube/ppc32 port Copyright (C) 2004 Albert Herranz
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 *
17 */
18
19#include <linux/sys.h>
20#include <asm/unistd.h>
21#include <asm/errno.h>
22#include <asm/reg.h>
23#include <asm/page.h>
24#include <asm/cache.h>
25#include <asm/cputable.h>
26#include <asm/mmu.h>
27#include <asm/ppc_asm.h>
28#include <asm/thread_info.h>
29#include <asm/asm-offsets.h>
30#include <asm/processor.h>
31#include <asm/kexec.h>
32#include <asm/bug.h>
33
34	.text
35
36#ifdef CONFIG_IRQSTACKS
37_GLOBAL(call_do_softirq)
38	mflr	r0
39	stw	r0,4(r1)
40	stwu	r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
41	mr	r1,r3
42	bl	__do_softirq
43	lwz	r1,0(r1)
44	lwz	r0,4(r1)
45	mtlr	r0
46	blr
47
48_GLOBAL(call_handle_irq)
49	mflr	r0
50	stw	r0,4(r1)
51	mtctr	r6
52	stwu	r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r5)
53	mr	r1,r5
54	bctrl
55	lwz	r1,0(r1)
56	lwz	r0,4(r1)
57	mtlr	r0
58	blr
59#endif /* CONFIG_IRQSTACKS */
60
61/*
62 * This returns the high 64 bits of the product of two 64-bit numbers.
63 */
64_GLOBAL(mulhdu)
65	cmpwi	r6,0
66	cmpwi	cr1,r3,0
67	mr	r10,r4
68	mulhwu	r4,r4,r5
69	beq	1f
70	mulhwu	r0,r10,r6
71	mullw	r7,r10,r5
72	addc	r7,r0,r7
73	addze	r4,r4
741:	beqlr	cr1		/* all done if high part of A is 0 */
75	mr	r10,r3
76	mullw	r9,r3,r5
77	mulhwu	r3,r3,r5
78	beq	2f
79	mullw	r0,r10,r6
80	mulhwu	r8,r10,r6
81	addc	r7,r0,r7
82	adde	r4,r4,r8
83	addze	r3,r3
842:	addc	r4,r4,r9
85	addze	r3,r3
86	blr
87
88/*
89 * sub_reloc_offset(x) returns x - reloc_offset().
90 */
91_GLOBAL(sub_reloc_offset)
92	mflr	r0
93	bl	1f
941:	mflr	r5
95	lis	r4,1b@ha
96	addi	r4,r4,1b@l
97	subf	r5,r4,r5
98	subf	r3,r5,r3
99	mtlr	r0
100	blr
101
102/*
103 * reloc_got2 runs through the .got2 section adding an offset
104 * to each entry.
105 */
106_GLOBAL(reloc_got2)
107	mflr	r11
108	lis	r7,__got2_start@ha
109	addi	r7,r7,__got2_start@l
110	lis	r8,__got2_end@ha
111	addi	r8,r8,__got2_end@l
112	subf	r8,r7,r8
113	srwi.	r8,r8,2
114	beqlr
115	mtctr	r8
116	bl	1f
1171:	mflr	r0
118	lis	r4,1b@ha
119	addi	r4,r4,1b@l
120	subf	r0,r4,r0
121	add	r7,r0,r7
1222:	lwz	r0,0(r7)
123	add	r0,r0,r3
124	stw	r0,0(r7)
125	addi	r7,r7,4
126	bdnz	2b
127	mtlr	r11
128	blr
129
130/*
131 * call_setup_cpu - call the setup_cpu function for this cpu
132 * r3 = data offset, r24 = cpu number
133 *
134 * Setup function is called with:
135 *   r3 = data offset
136 *   r4 = ptr to CPU spec (relocated)
137 */
138_GLOBAL(call_setup_cpu)
139	addis	r4,r3,cur_cpu_spec@ha
140	addi	r4,r4,cur_cpu_spec@l
141	lwz	r4,0(r4)
142	add	r4,r4,r3
143	lwz	r5,CPU_SPEC_SETUP(r4)
144	cmpwi	0,r5,0
145	add	r5,r5,r3
146	beqlr
147	mtctr	r5
148	bctr
149
150#if defined(CONFIG_CPU_FREQ_PMAC) && defined(CONFIG_6xx)
151
152/* This gets called by via-pmu.c to switch the PLL selection
153 * on 750fx CPU. This function should really be moved to some
154 * other place (as most of the cpufreq code in via-pmu
155 */
156_GLOBAL(low_choose_750fx_pll)
157	/* Clear MSR:EE */
158	mfmsr	r7
159	rlwinm	r0,r7,0,17,15
160	mtmsr	r0
161
162	/* If switching to PLL1, disable HID0:BTIC */
163	cmplwi	cr0,r3,0
164	beq	1f
165	mfspr	r5,SPRN_HID0
166	rlwinm	r5,r5,0,27,25
167	sync
168	mtspr	SPRN_HID0,r5
169	isync
170	sync
171
1721:
173	/* Calc new HID1 value */
174	mfspr	r4,SPRN_HID1	/* Build a HID1:PS bit from parameter */
175	rlwinm	r5,r3,16,15,15	/* Clear out HID1:PS from value read */
176	rlwinm	r4,r4,0,16,14	/* Could have I used rlwimi here ? */
177	or	r4,r4,r5
178	mtspr	SPRN_HID1,r4
179
180	/* Store new HID1 image */
181	rlwinm	r6,r1,0,0,(31-THREAD_SHIFT)
182	lwz	r6,TI_CPU(r6)
183	slwi	r6,r6,2
184	addis	r6,r6,nap_save_hid1@ha
185	stw	r4,nap_save_hid1@l(r6)
186
187	/* If switching to PLL0, enable HID0:BTIC */
188	cmplwi	cr0,r3,0
189	bne	1f
190	mfspr	r5,SPRN_HID0
191	ori	r5,r5,HID0_BTIC
192	sync
193	mtspr	SPRN_HID0,r5
194	isync
195	sync
196
1971:
198	/* Return */
199	mtmsr	r7
200	blr
201
202_GLOBAL(low_choose_7447a_dfs)
203	/* Clear MSR:EE */
204	mfmsr	r7
205	rlwinm	r0,r7,0,17,15
206	mtmsr	r0
207
208	/* Calc new HID1 value */
209	mfspr	r4,SPRN_HID1
210	insrwi	r4,r3,1,9	/* insert parameter into bit 9 */
211	sync
212	mtspr	SPRN_HID1,r4
213	sync
214	isync
215
216	/* Return */
217	mtmsr	r7
218	blr
219
220#endif /* CONFIG_CPU_FREQ_PMAC && CONFIG_6xx */
221
222/*
223 * complement mask on the msr then "or" some values on.
224 *     _nmask_and_or_msr(nmask, value_to_or)
225 */
226_GLOBAL(_nmask_and_or_msr)
227	mfmsr	r0		/* Get current msr */
228	andc	r0,r0,r3	/* And off the bits set in r3 (first parm) */
229	or	r0,r0,r4	/* Or on the bits in r4 (second parm) */
230	SYNC			/* Some chip revs have problems here... */
231	mtmsr	r0		/* Update machine state */
232	isync
233	blr			/* Done */
234
235#ifdef CONFIG_40x
236
237/*
238 * Do an IO access in real mode
239 */
240_GLOBAL(real_readb)
241	mfmsr	r7
242	ori	r0,r7,MSR_DR
243	xori	r0,r0,MSR_DR
244	sync
245	mtmsr	r0
246	sync
247	isync
248	lbz	r3,0(r3)
249	sync
250	mtmsr	r7
251	sync
252	isync
253	blr
254
255	/*
256 * Do an IO access in real mode
257 */
258_GLOBAL(real_writeb)
259	mfmsr	r7
260	ori	r0,r7,MSR_DR
261	xori	r0,r0,MSR_DR
262	sync
263	mtmsr	r0
264	sync
265	isync
266	stb	r3,0(r4)
267	sync
268	mtmsr	r7
269	sync
270	isync
271	blr
272
273#endif /* CONFIG_40x */
274
275
276/*
277 * Flush instruction cache.
278 * This is a no-op on the 601.
279 */
280_GLOBAL(flush_instruction_cache)
281#if defined(CONFIG_8xx)
282	isync
283	lis	r5, IDC_INVALL@h
284	mtspr	SPRN_IC_CST, r5
285#elif defined(CONFIG_4xx)
286#ifdef CONFIG_403GCX
287	li      r3, 512
288	mtctr   r3
289	lis     r4, KERNELBASE@h
2901:	iccci   0, r4
291	addi    r4, r4, 16
292	bdnz    1b
293#else
294	lis	r3, KERNELBASE@h
295	iccci	0,r3
296#endif
297#elif CONFIG_FSL_BOOKE
298BEGIN_FTR_SECTION
299	mfspr   r3,SPRN_L1CSR0
300	ori     r3,r3,L1CSR0_CFI|L1CSR0_CLFC
301	/* msync; isync recommended here */
302	mtspr   SPRN_L1CSR0,r3
303	isync
304	blr
305END_FTR_SECTION_IFSET(CPU_FTR_UNIFIED_ID_CACHE)
306	mfspr	r3,SPRN_L1CSR1
307	ori	r3,r3,L1CSR1_ICFI|L1CSR1_ICLFR
308	mtspr	SPRN_L1CSR1,r3
309#else
310	mfspr	r3,SPRN_PVR
311	rlwinm	r3,r3,16,16,31
312	cmpwi	0,r3,1
313	beqlr			/* for 601, do nothing */
314	/* 603/604 processor - use invalidate-all bit in HID0 */
315	mfspr	r3,SPRN_HID0
316	ori	r3,r3,HID0_ICFI
317	mtspr	SPRN_HID0,r3
318#endif /* CONFIG_8xx/4xx */
319	isync
320	blr
321
322/*
323 * Write any modified data cache blocks out to memory
324 * and invalidate the corresponding instruction cache blocks.
325 * This is a no-op on the 601.
326 *
327 * flush_icache_range(unsigned long start, unsigned long stop)
328 */
329_KPROBE(__flush_icache_range)
330BEGIN_FTR_SECTION
331	blr				/* for 601, do nothing */
332END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
333	li	r5,L1_CACHE_BYTES-1
334	andc	r3,r3,r5
335	subf	r4,r3,r4
336	add	r4,r4,r5
337	srwi.	r4,r4,L1_CACHE_SHIFT
338	beqlr
339	mtctr	r4
340	mr	r6,r3
3411:	dcbst	0,r3
342	addi	r3,r3,L1_CACHE_BYTES
343	bdnz	1b
344	sync				/* wait for dcbst's to get to ram */
345#ifndef CONFIG_44x
346	mtctr	r4
3472:	icbi	0,r6
348	addi	r6,r6,L1_CACHE_BYTES
349	bdnz	2b
350#else
351	/* Flash invalidate on 44x because we are passed kmapped addresses and
352	   this doesn't work for userspace pages due to the virtually tagged
353	   icache.  Sigh. */
354	iccci	0, r0
355#endif
356	sync				/* additional sync needed on g4 */
357	isync
358	blr
359/*
360 * Write any modified data cache blocks out to memory.
361 * Does not invalidate the corresponding cache lines (especially for
362 * any corresponding instruction cache).
363 *
364 * clean_dcache_range(unsigned long start, unsigned long stop)
365 */
366_GLOBAL(clean_dcache_range)
367	li	r5,L1_CACHE_BYTES-1
368	andc	r3,r3,r5
369	subf	r4,r3,r4
370	add	r4,r4,r5
371	srwi.	r4,r4,L1_CACHE_SHIFT
372	beqlr
373	mtctr	r4
374
3751:	dcbst	0,r3
376	addi	r3,r3,L1_CACHE_BYTES
377	bdnz	1b
378	sync				/* wait for dcbst's to get to ram */
379	blr
380
381/*
382 * Write any modified data cache blocks out to memory and invalidate them.
383 * Does not invalidate the corresponding instruction cache blocks.
384 *
385 * flush_dcache_range(unsigned long start, unsigned long stop)
386 */
387_GLOBAL(flush_dcache_range)
388	li	r5,L1_CACHE_BYTES-1
389	andc	r3,r3,r5
390	subf	r4,r3,r4
391	add	r4,r4,r5
392	srwi.	r4,r4,L1_CACHE_SHIFT
393	beqlr
394	mtctr	r4
395
3961:	dcbf	0,r3
397	addi	r3,r3,L1_CACHE_BYTES
398	bdnz	1b
399	sync				/* wait for dcbst's to get to ram */
400	blr
401
402/*
403 * Like above, but invalidate the D-cache.  This is used by the 8xx
404 * to invalidate the cache so the PPC core doesn't get stale data
405 * from the CPM (no cache snooping here :-).
406 *
407 * invalidate_dcache_range(unsigned long start, unsigned long stop)
408 */
409_GLOBAL(invalidate_dcache_range)
410	li	r5,L1_CACHE_BYTES-1
411	andc	r3,r3,r5
412	subf	r4,r3,r4
413	add	r4,r4,r5
414	srwi.	r4,r4,L1_CACHE_SHIFT
415	beqlr
416	mtctr	r4
417
4181:	dcbi	0,r3
419	addi	r3,r3,L1_CACHE_BYTES
420	bdnz	1b
421	sync				/* wait for dcbi's to get to ram */
422	blr
423
424/*
425 * Flush a particular page from the data cache to RAM.
426 * Note: this is necessary because the instruction cache does *not*
427 * snoop from the data cache.
428 * This is a no-op on the 601 which has a unified cache.
429 *
430 *	void __flush_dcache_icache(void *page)
431 */
432_GLOBAL(__flush_dcache_icache)
433BEGIN_FTR_SECTION
434	blr
435END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
436	rlwinm	r3,r3,0,0,31-PAGE_SHIFT		/* Get page base address */
437	li	r4,PAGE_SIZE/L1_CACHE_BYTES	/* Number of lines in a page */
438	mtctr	r4
439	mr	r6,r3
4400:	dcbst	0,r3				/* Write line to ram */
441	addi	r3,r3,L1_CACHE_BYTES
442	bdnz	0b
443	sync
444#ifndef CONFIG_44x
445	/* We don't flush the icache on 44x. Those have a virtual icache
446	 * and we don't have access to the virtual address here (it's
447	 * not the page vaddr but where it's mapped in user space). The
448	 * flushing of the icache on these is handled elsewhere, when
449	 * a change in the address space occurs, before returning to
450	 * user space
451	 */
452	mtctr	r4
4531:	icbi	0,r6
454	addi	r6,r6,L1_CACHE_BYTES
455	bdnz	1b
456	sync
457	isync
458#endif /* CONFIG_44x */
459	blr
460
461/*
462 * Flush a particular page from the data cache to RAM, identified
463 * by its physical address.  We turn off the MMU so we can just use
464 * the physical address (this may be a highmem page without a kernel
465 * mapping).
466 *
467 *	void __flush_dcache_icache_phys(unsigned long physaddr)
468 */
469_GLOBAL(__flush_dcache_icache_phys)
470BEGIN_FTR_SECTION
471	blr					/* for 601, do nothing */
472END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
473	mfmsr	r10
474	rlwinm	r0,r10,0,28,26			/* clear DR */
475	mtmsr	r0
476	isync
477	rlwinm	r3,r3,0,0,31-PAGE_SHIFT		/* Get page base address */
478	li	r4,PAGE_SIZE/L1_CACHE_BYTES	/* Number of lines in a page */
479	mtctr	r4
480	mr	r6,r3
4810:	dcbst	0,r3				/* Write line to ram */
482	addi	r3,r3,L1_CACHE_BYTES
483	bdnz	0b
484	sync
485	mtctr	r4
4861:	icbi	0,r6
487	addi	r6,r6,L1_CACHE_BYTES
488	bdnz	1b
489	sync
490	mtmsr	r10				/* restore DR */
491	isync
492	blr
493
494/*
495 * Clear pages using the dcbz instruction, which doesn't cause any
496 * memory traffic (except to write out any cache lines which get
497 * displaced).  This only works on cacheable memory.
498 *
499 * void clear_pages(void *page, int order) ;
500 */
501_GLOBAL(clear_pages)
502	li	r0,PAGE_SIZE/L1_CACHE_BYTES
503	slw	r0,r0,r4
504	mtctr	r0
5051:	dcbz	0,r3
506	addi	r3,r3,L1_CACHE_BYTES
507	bdnz	1b
508	blr
509
510/*
511 * Copy a whole page.  We use the dcbz instruction on the destination
512 * to reduce memory traffic (it eliminates the unnecessary reads of
513 * the destination into cache).  This requires that the destination
514 * is cacheable.
515 */
516#define COPY_16_BYTES		\
517	lwz	r6,4(r4);	\
518	lwz	r7,8(r4);	\
519	lwz	r8,12(r4);	\
520	lwzu	r9,16(r4);	\
521	stw	r6,4(r3);	\
522	stw	r7,8(r3);	\
523	stw	r8,12(r3);	\
524	stwu	r9,16(r3)
525
526_GLOBAL(copy_page)
527	addi	r3,r3,-4
528	addi	r4,r4,-4
529
530	li	r5,4
531
532#if MAX_COPY_PREFETCH > 1
533	li	r0,MAX_COPY_PREFETCH
534	li	r11,4
535	mtctr	r0
53611:	dcbt	r11,r4
537	addi	r11,r11,L1_CACHE_BYTES
538	bdnz	11b
539#else /* MAX_COPY_PREFETCH == 1 */
540	dcbt	r5,r4
541	li	r11,L1_CACHE_BYTES+4
542#endif /* MAX_COPY_PREFETCH */
543	li	r0,PAGE_SIZE/L1_CACHE_BYTES - MAX_COPY_PREFETCH
544	crclr	4*cr0+eq
5452:
546	mtctr	r0
5471:
548	dcbt	r11,r4
549	dcbz	r5,r3
550	COPY_16_BYTES
551#if L1_CACHE_BYTES >= 32
552	COPY_16_BYTES
553#if L1_CACHE_BYTES >= 64
554	COPY_16_BYTES
555	COPY_16_BYTES
556#if L1_CACHE_BYTES >= 128
557	COPY_16_BYTES
558	COPY_16_BYTES
559	COPY_16_BYTES
560	COPY_16_BYTES
561#endif
562#endif
563#endif
564	bdnz	1b
565	beqlr
566	crnot	4*cr0+eq,4*cr0+eq
567	li	r0,MAX_COPY_PREFETCH
568	li	r11,4
569	b	2b
570
571/*
572 * void atomic_clear_mask(atomic_t mask, atomic_t *addr)
573 * void atomic_set_mask(atomic_t mask, atomic_t *addr);
574 */
575_GLOBAL(atomic_clear_mask)
57610:	lwarx	r5,0,r4
577	andc	r5,r5,r3
578	PPC405_ERR77(0,r4)
579	stwcx.	r5,0,r4
580	bne-	10b
581	blr
582_GLOBAL(atomic_set_mask)
58310:	lwarx	r5,0,r4
584	or	r5,r5,r3
585	PPC405_ERR77(0,r4)
586	stwcx.	r5,0,r4
587	bne-	10b
588	blr
589
590/*
591 * Extended precision shifts.
592 *
593 * Updated to be valid for shift counts from 0 to 63 inclusive.
594 * -- Gabriel
595 *
596 * R3/R4 has 64 bit value
597 * R5    has shift count
598 * result in R3/R4
599 *
600 *  ashrdi3: arithmetic right shift (sign propagation)
601 *  lshrdi3: logical right shift
602 *  ashldi3: left shift
603 */
604_GLOBAL(__ashrdi3)
605	subfic	r6,r5,32
606	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
607	addi	r7,r5,32	# could be xori, or addi with -32
608	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
609	rlwinm	r8,r7,0,32	# t3 = (count < 32) ? 32 : 0
610	sraw	r7,r3,r7	# t2 = MSW >> (count-32)
611	or	r4,r4,r6	# LSW |= t1
612	slw	r7,r7,r8	# t2 = (count < 32) ? 0 : t2
613	sraw	r3,r3,r5	# MSW = MSW >> count
614	or	r4,r4,r7	# LSW |= t2
615	blr
616
617_GLOBAL(__ashldi3)
618	subfic	r6,r5,32
619	slw	r3,r3,r5	# MSW = count > 31 ? 0 : MSW << count
620	addi	r7,r5,32	# could be xori, or addi with -32
621	srw	r6,r4,r6	# t1 = count > 31 ? 0 : LSW >> (32-count)
622	slw	r7,r4,r7	# t2 = count < 32 ? 0 : LSW << (count-32)
623	or	r3,r3,r6	# MSW |= t1
624	slw	r4,r4,r5	# LSW = LSW << count
625	or	r3,r3,r7	# MSW |= t2
626	blr
627
628_GLOBAL(__lshrdi3)
629	subfic	r6,r5,32
630	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
631	addi	r7,r5,32	# could be xori, or addi with -32
632	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
633	srw	r7,r3,r7	# t2 = count < 32 ? 0 : MSW >> (count-32)
634	or	r4,r4,r6	# LSW |= t1
635	srw	r3,r3,r5	# MSW = MSW >> count
636	or	r4,r4,r7	# LSW |= t2
637	blr
638
639/*
640 * 64-bit comparison: __ucmpdi2(u64 a, u64 b)
641 * Returns 0 if a < b, 1 if a == b, 2 if a > b.
642 */
643_GLOBAL(__ucmpdi2)
644	cmplw	r3,r5
645	li	r3,1
646	bne	1f
647	cmplw	r4,r6
648	beqlr
6491:	li	r3,0
650	bltlr
651	li	r3,2
652	blr
653
654_GLOBAL(abs)
655	srawi	r4,r3,31
656	xor	r3,r3,r4
657	sub	r3,r3,r4
658	blr
659
660/*
661 * Create a kernel thread
662 *   kernel_thread(fn, arg, flags)
663 */
664_GLOBAL(kernel_thread)
665	stwu	r1,-16(r1)
666	stw	r30,8(r1)
667	stw	r31,12(r1)
668	mr	r30,r3		/* function */
669	mr	r31,r4		/* argument */
670	ori	r3,r5,CLONE_VM	/* flags */
671	oris	r3,r3,CLONE_UNTRACED>>16
672	li	r4,0		/* new sp (unused) */
673	li	r0,__NR_clone
674	sc
675	bns+	1f		/* did system call indicate error? */
676	neg	r3,r3		/* if so, make return code negative */
6771:	cmpwi	0,r3,0		/* parent or child? */
678	bne	2f		/* return if parent */
679	li	r0,0		/* make top-level stack frame */
680	stwu	r0,-16(r1)
681	mtlr	r30		/* fn addr in lr */
682	mr	r3,r31		/* load arg and call fn */
683	PPC440EP_ERR42
684	blrl
685	li	r0,__NR_exit	/* exit if function returns */
686	li	r3,0
687	sc
6882:	lwz	r30,8(r1)
689	lwz	r31,12(r1)
690	addi	r1,r1,16
691	blr
692
693/*
694 * This routine is just here to keep GCC happy - sigh...
695 */
696_GLOBAL(__main)
697	blr
698
699#ifdef CONFIG_KEXEC
700	/*
701	 * Must be relocatable PIC code callable as a C function.
702	 */
703	.globl relocate_new_kernel
704relocate_new_kernel:
705	/* r3 = page_list   */
706	/* r4 = reboot_code_buffer */
707	/* r5 = start_address      */
708
709	li	r0, 0
710
711	/*
712	 * Set Machine Status Register to a known status,
713	 * switch the MMU off and jump to 1: in a single step.
714	 */
715
716	mr	r8, r0
717	ori     r8, r8, MSR_RI|MSR_ME
718	mtspr	SPRN_SRR1, r8
719	addi	r8, r4, 1f - relocate_new_kernel
720	mtspr	SPRN_SRR0, r8
721	sync
722	rfi
723
7241:
725	/* from this point address translation is turned off */
726	/* and interrupts are disabled */
727
728	/* set a new stack at the bottom of our page... */
729	/* (not really needed now) */
730	addi	r1, r4, KEXEC_CONTROL_PAGE_SIZE - 8 /* for LR Save+Back Chain */
731	stw	r0, 0(r1)
732
733	/* Do the copies */
734	li	r6, 0 /* checksum */
735	mr	r0, r3
736	b	1f
737
7380:	/* top, read another word for the indirection page */
739	lwzu	r0, 4(r3)
740
7411:
742	/* is it a destination page? (r8) */
743	rlwinm.	r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
744	beq	2f
745
746	rlwinm	r8, r0, 0, 0, 19 /* clear kexec flags, page align */
747	b	0b
748
7492:	/* is it an indirection page? (r3) */
750	rlwinm.	r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
751	beq	2f
752
753	rlwinm	r3, r0, 0, 0, 19 /* clear kexec flags, page align */
754	subi	r3, r3, 4
755	b	0b
756
7572:	/* are we done? */
758	rlwinm.	r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
759	beq	2f
760	b	3f
761
7622:	/* is it a source page? (r9) */
763	rlwinm.	r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
764	beq	0b
765
766	rlwinm	r9, r0, 0, 0, 19 /* clear kexec flags, page align */
767
768	li	r7, PAGE_SIZE / 4
769	mtctr   r7
770	subi    r9, r9, 4
771	subi    r8, r8, 4
7729:
773	lwzu    r0, 4(r9)  /* do the copy */
774	xor	r6, r6, r0
775	stwu    r0, 4(r8)
776	dcbst	0, r8
777	sync
778	icbi	0, r8
779	bdnz    9b
780
781	addi    r9, r9, 4
782	addi    r8, r8, 4
783	b	0b
784
7853:
786
787	/* To be certain of avoiding problems with self-modifying code
788	 * execute a serializing instruction here.
789	 */
790	isync
791	sync
792
793	/* jump to the entry point, usually the setup routine */
794	mtlr	r5
795	blrl
796
7971:	b	1b
798
799relocate_new_kernel_end:
800
801	.globl relocate_new_kernel_size
802relocate_new_kernel_size:
803	.long relocate_new_kernel_end - relocate_new_kernel
804#endif
805