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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	mtctr	r4
3462:	icbi	0,r6
347	addi	r6,r6,L1_CACHE_BYTES
348	bdnz	2b
349	sync				/* additional sync needed on g4 */
350	isync
351	blr
352/*
353 * Write any modified data cache blocks out to memory.
354 * Does not invalidate the corresponding cache lines (especially for
355 * any corresponding instruction cache).
356 *
357 * clean_dcache_range(unsigned long start, unsigned long stop)
358 */
359_GLOBAL(clean_dcache_range)
360	li	r5,L1_CACHE_BYTES-1
361	andc	r3,r3,r5
362	subf	r4,r3,r4
363	add	r4,r4,r5
364	srwi.	r4,r4,L1_CACHE_SHIFT
365	beqlr
366	mtctr	r4
367
3681:	dcbst	0,r3
369	addi	r3,r3,L1_CACHE_BYTES
370	bdnz	1b
371	sync				/* wait for dcbst's to get to ram */
372	blr
373
374/*
375 * Write any modified data cache blocks out to memory and invalidate them.
376 * Does not invalidate the corresponding instruction cache blocks.
377 *
378 * flush_dcache_range(unsigned long start, unsigned long stop)
379 */
380_GLOBAL(flush_dcache_range)
381	li	r5,L1_CACHE_BYTES-1
382	andc	r3,r3,r5
383	subf	r4,r3,r4
384	add	r4,r4,r5
385	srwi.	r4,r4,L1_CACHE_SHIFT
386	beqlr
387	mtctr	r4
388
3891:	dcbf	0,r3
390	addi	r3,r3,L1_CACHE_BYTES
391	bdnz	1b
392	sync				/* wait for dcbst's to get to ram */
393	blr
394
395/*
396 * Like above, but invalidate the D-cache.  This is used by the 8xx
397 * to invalidate the cache so the PPC core doesn't get stale data
398 * from the CPM (no cache snooping here :-).
399 *
400 * invalidate_dcache_range(unsigned long start, unsigned long stop)
401 */
402_GLOBAL(invalidate_dcache_range)
403	li	r5,L1_CACHE_BYTES-1
404	andc	r3,r3,r5
405	subf	r4,r3,r4
406	add	r4,r4,r5
407	srwi.	r4,r4,L1_CACHE_SHIFT
408	beqlr
409	mtctr	r4
410
4111:	dcbi	0,r3
412	addi	r3,r3,L1_CACHE_BYTES
413	bdnz	1b
414	sync				/* wait for dcbi's to get to ram */
415	blr
416
417/*
418 * Flush a particular page from the data cache to RAM.
419 * Note: this is necessary because the instruction cache does *not*
420 * snoop from the data cache.
421 * This is a no-op on the 601 which has a unified cache.
422 *
423 *	void __flush_dcache_icache(void *page)
424 */
425_GLOBAL(__flush_dcache_icache)
426BEGIN_FTR_SECTION
427	blr
428END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
429	rlwinm	r3,r3,0,0,31-PAGE_SHIFT		/* Get page base address */
430	li	r4,PAGE_SIZE/L1_CACHE_BYTES	/* Number of lines in a page */
431	mtctr	r4
432	mr	r6,r3
4330:	dcbst	0,r3				/* Write line to ram */
434	addi	r3,r3,L1_CACHE_BYTES
435	bdnz	0b
436	sync
437#ifndef CONFIG_44x
438	/* We don't flush the icache on 44x. Those have a virtual icache
439	 * and we don't have access to the virtual address here (it's
440	 * not the page vaddr but where it's mapped in user space). The
441	 * flushing of the icache on these is handled elsewhere, when
442	 * a change in the address space occurs, before returning to
443	 * user space
444	 */
445	mtctr	r4
4461:	icbi	0,r6
447	addi	r6,r6,L1_CACHE_BYTES
448	bdnz	1b
449	sync
450	isync
451#endif /* CONFIG_44x */
452	blr
453
454/*
455 * Flush a particular page from the data cache to RAM, identified
456 * by its physical address.  We turn off the MMU so we can just use
457 * the physical address (this may be a highmem page without a kernel
458 * mapping).
459 *
460 *	void __flush_dcache_icache_phys(unsigned long physaddr)
461 */
462_GLOBAL(__flush_dcache_icache_phys)
463BEGIN_FTR_SECTION
464	blr					/* for 601, do nothing */
465END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
466	mfmsr	r10
467	rlwinm	r0,r10,0,28,26			/* clear DR */
468	mtmsr	r0
469	isync
470	rlwinm	r3,r3,0,0,31-PAGE_SHIFT		/* Get page base address */
471	li	r4,PAGE_SIZE/L1_CACHE_BYTES	/* Number of lines in a page */
472	mtctr	r4
473	mr	r6,r3
4740:	dcbst	0,r3				/* Write line to ram */
475	addi	r3,r3,L1_CACHE_BYTES
476	bdnz	0b
477	sync
478	mtctr	r4
4791:	icbi	0,r6
480	addi	r6,r6,L1_CACHE_BYTES
481	bdnz	1b
482	sync
483	mtmsr	r10				/* restore DR */
484	isync
485	blr
486
487/*
488 * Clear pages using the dcbz instruction, which doesn't cause any
489 * memory traffic (except to write out any cache lines which get
490 * displaced).  This only works on cacheable memory.
491 *
492 * void clear_pages(void *page, int order) ;
493 */
494_GLOBAL(clear_pages)
495	li	r0,PAGE_SIZE/L1_CACHE_BYTES
496	slw	r0,r0,r4
497	mtctr	r0
498#ifdef CONFIG_8xx
499	li	r4, 0
5001:	stw	r4, 0(r3)
501	stw	r4, 4(r3)
502	stw	r4, 8(r3)
503	stw	r4, 12(r3)
504#else
5051:	dcbz	0,r3
506#endif
507	addi	r3,r3,L1_CACHE_BYTES
508	bdnz	1b
509	blr
510
511/*
512 * Copy a whole page.  We use the dcbz instruction on the destination
513 * to reduce memory traffic (it eliminates the unnecessary reads of
514 * the destination into cache).  This requires that the destination
515 * is cacheable.
516 */
517#define COPY_16_BYTES		\
518	lwz	r6,4(r4);	\
519	lwz	r7,8(r4);	\
520	lwz	r8,12(r4);	\
521	lwzu	r9,16(r4);	\
522	stw	r6,4(r3);	\
523	stw	r7,8(r3);	\
524	stw	r8,12(r3);	\
525	stwu	r9,16(r3)
526
527_GLOBAL(copy_page)
528	addi	r3,r3,-4
529	addi	r4,r4,-4
530
531#ifdef CONFIG_8xx
532	/* don't use prefetch on 8xx */
533    	li	r0,4096/L1_CACHE_BYTES
534	mtctr	r0
5351:	COPY_16_BYTES
536	bdnz	1b
537	blr
538
539#else	/* not 8xx, we can prefetch */
540	li	r5,4
541
542#if MAX_COPY_PREFETCH > 1
543	li	r0,MAX_COPY_PREFETCH
544	li	r11,4
545	mtctr	r0
54611:	dcbt	r11,r4
547	addi	r11,r11,L1_CACHE_BYTES
548	bdnz	11b
549#else /* MAX_COPY_PREFETCH == 1 */
550	dcbt	r5,r4
551	li	r11,L1_CACHE_BYTES+4
552#endif /* MAX_COPY_PREFETCH */
553	li	r0,PAGE_SIZE/L1_CACHE_BYTES - MAX_COPY_PREFETCH
554	crclr	4*cr0+eq
5552:
556	mtctr	r0
5571:
558	dcbt	r11,r4
559	dcbz	r5,r3
560	COPY_16_BYTES
561#if L1_CACHE_BYTES >= 32
562	COPY_16_BYTES
563#if L1_CACHE_BYTES >= 64
564	COPY_16_BYTES
565	COPY_16_BYTES
566#if L1_CACHE_BYTES >= 128
567	COPY_16_BYTES
568	COPY_16_BYTES
569	COPY_16_BYTES
570	COPY_16_BYTES
571#endif
572#endif
573#endif
574	bdnz	1b
575	beqlr
576	crnot	4*cr0+eq,4*cr0+eq
577	li	r0,MAX_COPY_PREFETCH
578	li	r11,4
579	b	2b
580#endif	/* CONFIG_8xx */
581
582/*
583 * void atomic_clear_mask(atomic_t mask, atomic_t *addr)
584 * void atomic_set_mask(atomic_t mask, atomic_t *addr);
585 */
586_GLOBAL(atomic_clear_mask)
58710:	lwarx	r5,0,r4
588	andc	r5,r5,r3
589	PPC405_ERR77(0,r4)
590	stwcx.	r5,0,r4
591	bne-	10b
592	blr
593_GLOBAL(atomic_set_mask)
59410:	lwarx	r5,0,r4
595	or	r5,r5,r3
596	PPC405_ERR77(0,r4)
597	stwcx.	r5,0,r4
598	bne-	10b
599	blr
600
601/*
602 * Extended precision shifts.
603 *
604 * Updated to be valid for shift counts from 0 to 63 inclusive.
605 * -- Gabriel
606 *
607 * R3/R4 has 64 bit value
608 * R5    has shift count
609 * result in R3/R4
610 *
611 *  ashrdi3: arithmetic right shift (sign propagation)
612 *  lshrdi3: logical right shift
613 *  ashldi3: left shift
614 */
615_GLOBAL(__ashrdi3)
616	subfic	r6,r5,32
617	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
618	addi	r7,r5,32	# could be xori, or addi with -32
619	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
620	rlwinm	r8,r7,0,32	# t3 = (count < 32) ? 32 : 0
621	sraw	r7,r3,r7	# t2 = MSW >> (count-32)
622	or	r4,r4,r6	# LSW |= t1
623	slw	r7,r7,r8	# t2 = (count < 32) ? 0 : t2
624	sraw	r3,r3,r5	# MSW = MSW >> count
625	or	r4,r4,r7	# LSW |= t2
626	blr
627
628_GLOBAL(__ashldi3)
629	subfic	r6,r5,32
630	slw	r3,r3,r5	# MSW = count > 31 ? 0 : MSW << count
631	addi	r7,r5,32	# could be xori, or addi with -32
632	srw	r6,r4,r6	# t1 = count > 31 ? 0 : LSW >> (32-count)
633	slw	r7,r4,r7	# t2 = count < 32 ? 0 : LSW << (count-32)
634	or	r3,r3,r6	# MSW |= t1
635	slw	r4,r4,r5	# LSW = LSW << count
636	or	r3,r3,r7	# MSW |= t2
637	blr
638
639_GLOBAL(__lshrdi3)
640	subfic	r6,r5,32
641	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
642	addi	r7,r5,32	# could be xori, or addi with -32
643	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
644	srw	r7,r3,r7	# t2 = count < 32 ? 0 : MSW >> (count-32)
645	or	r4,r4,r6	# LSW |= t1
646	srw	r3,r3,r5	# MSW = MSW >> count
647	or	r4,r4,r7	# LSW |= t2
648	blr
649
650/*
651 * 64-bit comparison: __ucmpdi2(u64 a, u64 b)
652 * Returns 0 if a < b, 1 if a == b, 2 if a > b.
653 */
654_GLOBAL(__ucmpdi2)
655	cmplw	r3,r5
656	li	r3,1
657	bne	1f
658	cmplw	r4,r6
659	beqlr
6601:	li	r3,0
661	bltlr
662	li	r3,2
663	blr
664
665_GLOBAL(abs)
666	srawi	r4,r3,31
667	xor	r3,r3,r4
668	sub	r3,r3,r4
669	blr
670
671/*
672 * Create a kernel thread
673 *   kernel_thread(fn, arg, flags)
674 */
675_GLOBAL(kernel_thread)
676	stwu	r1,-16(r1)
677	stw	r30,8(r1)
678	stw	r31,12(r1)
679	mr	r30,r3		/* function */
680	mr	r31,r4		/* argument */
681	ori	r3,r5,CLONE_VM	/* flags */
682	oris	r3,r3,CLONE_UNTRACED>>16
683	li	r4,0		/* new sp (unused) */
684	li	r0,__NR_clone
685	sc
686	bns+	1f		/* did system call indicate error? */
687	neg	r3,r3		/* if so, make return code negative */
6881:	cmpwi	0,r3,0		/* parent or child? */
689	bne	2f		/* return if parent */
690	li	r0,0		/* make top-level stack frame */
691	stwu	r0,-16(r1)
692	mtlr	r30		/* fn addr in lr */
693	mr	r3,r31		/* load arg and call fn */
694	PPC440EP_ERR42
695	blrl
696	li	r0,__NR_exit	/* exit if function returns */
697	li	r3,0
698	sc
6992:	lwz	r30,8(r1)
700	lwz	r31,12(r1)
701	addi	r1,r1,16
702	blr
703
704/*
705 * This routine is just here to keep GCC happy - sigh...
706 */
707_GLOBAL(__main)
708	blr
709
710#ifdef CONFIG_KEXEC
711	/*
712	 * Must be relocatable PIC code callable as a C function.
713	 */
714	.globl relocate_new_kernel
715relocate_new_kernel:
716	/* r3 = page_list   */
717	/* r4 = reboot_code_buffer */
718	/* r5 = start_address      */
719
720	li	r0, 0
721
722	/*
723	 * Set Machine Status Register to a known status,
724	 * switch the MMU off and jump to 1: in a single step.
725	 */
726
727	mr	r8, r0
728	ori     r8, r8, MSR_RI|MSR_ME
729	mtspr	SPRN_SRR1, r8
730	addi	r8, r4, 1f - relocate_new_kernel
731	mtspr	SPRN_SRR0, r8
732	sync
733	rfi
734
7351:
736	/* from this point address translation is turned off */
737	/* and interrupts are disabled */
738
739	/* set a new stack at the bottom of our page... */
740	/* (not really needed now) */
741	addi	r1, r4, KEXEC_CONTROL_PAGE_SIZE - 8 /* for LR Save+Back Chain */
742	stw	r0, 0(r1)
743
744	/* Do the copies */
745	li	r6, 0 /* checksum */
746	mr	r0, r3
747	b	1f
748
7490:	/* top, read another word for the indirection page */
750	lwzu	r0, 4(r3)
751
7521:
753	/* is it a destination page? (r8) */
754	rlwinm.	r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
755	beq	2f
756
757	rlwinm	r8, r0, 0, 0, 19 /* clear kexec flags, page align */
758	b	0b
759
7602:	/* is it an indirection page? (r3) */
761	rlwinm.	r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
762	beq	2f
763
764	rlwinm	r3, r0, 0, 0, 19 /* clear kexec flags, page align */
765	subi	r3, r3, 4
766	b	0b
767
7682:	/* are we done? */
769	rlwinm.	r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
770	beq	2f
771	b	3f
772
7732:	/* is it a source page? (r9) */
774	rlwinm.	r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
775	beq	0b
776
777	rlwinm	r9, r0, 0, 0, 19 /* clear kexec flags, page align */
778
779	li	r7, PAGE_SIZE / 4
780	mtctr   r7
781	subi    r9, r9, 4
782	subi    r8, r8, 4
7839:
784	lwzu    r0, 4(r9)  /* do the copy */
785	xor	r6, r6, r0
786	stwu    r0, 4(r8)
787	dcbst	0, r8
788	sync
789	icbi	0, r8
790	bdnz    9b
791
792	addi    r9, r9, 4
793	addi    r8, r8, 4
794	b	0b
795
7963:
797
798	/* To be certain of avoiding problems with self-modifying code
799	 * execute a serializing instruction here.
800	 */
801	isync
802	sync
803
804	/* jump to the entry point, usually the setup routine */
805	mtlr	r5
806	blrl
807
8081:	b	1b
809
810relocate_new_kernel_end:
811
812	.globl relocate_new_kernel_size
813relocate_new_kernel_size:
814	.long relocate_new_kernel_end - relocate_new_kernel
815#endif
816