xref: /linux/arch/powerpc/kernel/misc_32.S (revision 93d546399c2b7d66a54d5fbd5eee17de19246bf6)
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
33	.text
34
35#ifdef CONFIG_IRQSTACKS
36_GLOBAL(call_do_softirq)
37	mflr	r0
38	stw	r0,4(r1)
39	stwu	r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3)
40	mr	r1,r3
41	bl	__do_softirq
42	lwz	r1,0(r1)
43	lwz	r0,4(r1)
44	mtlr	r0
45	blr
46
47_GLOBAL(call_handle_irq)
48	mflr	r0
49	stw	r0,4(r1)
50	mtctr	r6
51	stwu	r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r5)
52	mr	r1,r5
53	bctrl
54	lwz	r1,0(r1)
55	lwz	r0,4(r1)
56	mtlr	r0
57	blr
58#endif /* CONFIG_IRQSTACKS */
59
60/*
61 * This returns the high 64 bits of the product of two 64-bit numbers.
62 */
63_GLOBAL(mulhdu)
64	cmpwi	r6,0
65	cmpwi	cr1,r3,0
66	mr	r10,r4
67	mulhwu	r4,r4,r5
68	beq	1f
69	mulhwu	r0,r10,r6
70	mullw	r7,r10,r5
71	addc	r7,r0,r7
72	addze	r4,r4
731:	beqlr	cr1		/* all done if high part of A is 0 */
74	mr	r10,r3
75	mullw	r9,r3,r5
76	mulhwu	r3,r3,r5
77	beq	2f
78	mullw	r0,r10,r6
79	mulhwu	r8,r10,r6
80	addc	r7,r0,r7
81	adde	r4,r4,r8
82	addze	r3,r3
832:	addc	r4,r4,r9
84	addze	r3,r3
85	blr
86
87/*
88 * sub_reloc_offset(x) returns x - reloc_offset().
89 */
90_GLOBAL(sub_reloc_offset)
91	mflr	r0
92	bl	1f
931:	mflr	r5
94	lis	r4,1b@ha
95	addi	r4,r4,1b@l
96	subf	r5,r4,r5
97	subf	r3,r5,r3
98	mtlr	r0
99	blr
100
101/*
102 * reloc_got2 runs through the .got2 section adding an offset
103 * to each entry.
104 */
105_GLOBAL(reloc_got2)
106	mflr	r11
107	lis	r7,__got2_start@ha
108	addi	r7,r7,__got2_start@l
109	lis	r8,__got2_end@ha
110	addi	r8,r8,__got2_end@l
111	subf	r8,r7,r8
112	srwi.	r8,r8,2
113	beqlr
114	mtctr	r8
115	bl	1f
1161:	mflr	r0
117	lis	r4,1b@ha
118	addi	r4,r4,1b@l
119	subf	r0,r4,r0
120	add	r7,r0,r7
1212:	lwz	r0,0(r7)
122	add	r0,r0,r3
123	stw	r0,0(r7)
124	addi	r7,r7,4
125	bdnz	2b
126	mtlr	r11
127	blr
128
129/*
130 * call_setup_cpu - call the setup_cpu function for this cpu
131 * r3 = data offset, r24 = cpu number
132 *
133 * Setup function is called with:
134 *   r3 = data offset
135 *   r4 = ptr to CPU spec (relocated)
136 */
137_GLOBAL(call_setup_cpu)
138	addis	r4,r3,cur_cpu_spec@ha
139	addi	r4,r4,cur_cpu_spec@l
140	lwz	r4,0(r4)
141	add	r4,r4,r3
142	lwz	r5,CPU_SPEC_SETUP(r4)
143	cmpwi	0,r5,0
144	add	r5,r5,r3
145	beqlr
146	mtctr	r5
147	bctr
148
149#if defined(CONFIG_CPU_FREQ_PMAC) && defined(CONFIG_6xx)
150
151/* This gets called by via-pmu.c to switch the PLL selection
152 * on 750fx CPU. This function should really be moved to some
153 * other place (as most of the cpufreq code in via-pmu
154 */
155_GLOBAL(low_choose_750fx_pll)
156	/* Clear MSR:EE */
157	mfmsr	r7
158	rlwinm	r0,r7,0,17,15
159	mtmsr	r0
160
161	/* If switching to PLL1, disable HID0:BTIC */
162	cmplwi	cr0,r3,0
163	beq	1f
164	mfspr	r5,SPRN_HID0
165	rlwinm	r5,r5,0,27,25
166	sync
167	mtspr	SPRN_HID0,r5
168	isync
169	sync
170
1711:
172	/* Calc new HID1 value */
173	mfspr	r4,SPRN_HID1	/* Build a HID1:PS bit from parameter */
174	rlwinm	r5,r3,16,15,15	/* Clear out HID1:PS from value read */
175	rlwinm	r4,r4,0,16,14	/* Could have I used rlwimi here ? */
176	or	r4,r4,r5
177	mtspr	SPRN_HID1,r4
178
179	/* Store new HID1 image */
180	rlwinm	r6,r1,0,0,(31-THREAD_SHIFT)
181	lwz	r6,TI_CPU(r6)
182	slwi	r6,r6,2
183	addis	r6,r6,nap_save_hid1@ha
184	stw	r4,nap_save_hid1@l(r6)
185
186	/* If switching to PLL0, enable HID0:BTIC */
187	cmplwi	cr0,r3,0
188	bne	1f
189	mfspr	r5,SPRN_HID0
190	ori	r5,r5,HID0_BTIC
191	sync
192	mtspr	SPRN_HID0,r5
193	isync
194	sync
195
1961:
197	/* Return */
198	mtmsr	r7
199	blr
200
201_GLOBAL(low_choose_7447a_dfs)
202	/* Clear MSR:EE */
203	mfmsr	r7
204	rlwinm	r0,r7,0,17,15
205	mtmsr	r0
206
207	/* Calc new HID1 value */
208	mfspr	r4,SPRN_HID1
209	insrwi	r4,r3,1,9	/* insert parameter into bit 9 */
210	sync
211	mtspr	SPRN_HID1,r4
212	sync
213	isync
214
215	/* Return */
216	mtmsr	r7
217	blr
218
219#endif /* CONFIG_CPU_FREQ_PMAC && CONFIG_6xx */
220
221/*
222 * complement mask on the msr then "or" some values on.
223 *     _nmask_and_or_msr(nmask, value_to_or)
224 */
225_GLOBAL(_nmask_and_or_msr)
226	mfmsr	r0		/* Get current msr */
227	andc	r0,r0,r3	/* And off the bits set in r3 (first parm) */
228	or	r0,r0,r4	/* Or on the bits in r4 (second parm) */
229	SYNC			/* Some chip revs have problems here... */
230	mtmsr	r0		/* Update machine state */
231	isync
232	blr			/* Done */
233
234#ifdef CONFIG_40x
235
236/*
237 * Do an IO access in real mode
238 */
239_GLOBAL(real_readb)
240	mfmsr	r7
241	ori	r0,r7,MSR_DR
242	xori	r0,r0,MSR_DR
243	sync
244	mtmsr	r0
245	sync
246	isync
247	lbz	r3,0(r3)
248	sync
249	mtmsr	r7
250	sync
251	isync
252	blr
253
254	/*
255 * Do an IO access in real mode
256 */
257_GLOBAL(real_writeb)
258	mfmsr	r7
259	ori	r0,r7,MSR_DR
260	xori	r0,r0,MSR_DR
261	sync
262	mtmsr	r0
263	sync
264	isync
265	stb	r3,0(r4)
266	sync
267	mtmsr	r7
268	sync
269	isync
270	blr
271
272#endif /* CONFIG_40x */
273
274/*
275 * Flush MMU TLB
276 */
277#ifndef CONFIG_FSL_BOOKE
278_GLOBAL(_tlbil_all)
279_GLOBAL(_tlbil_pid)
280#endif
281_GLOBAL(_tlbia)
282#if defined(CONFIG_40x)
283	sync			/* Flush to memory before changing mapping */
284	tlbia
285	isync			/* Flush shadow TLB */
286#elif defined(CONFIG_44x)
287	li	r3,0
288	sync
289
290	/* Load high watermark */
291	lis	r4,tlb_44x_hwater@ha
292	lwz	r5,tlb_44x_hwater@l(r4)
293
2941:	tlbwe	r3,r3,PPC44x_TLB_PAGEID
295	addi	r3,r3,1
296	cmpw	0,r3,r5
297	ble	1b
298
299	isync
300#elif defined(CONFIG_FSL_BOOKE)
301	/* Invalidate all entries in TLB0 */
302	li	r3, 0x04
303	tlbivax	0,3
304	/* Invalidate all entries in TLB1 */
305	li	r3, 0x0c
306	tlbivax	0,3
307	msync
308#ifdef CONFIG_SMP
309	tlbsync
310#endif /* CONFIG_SMP */
311#else /* !(CONFIG_40x || CONFIG_44x || CONFIG_FSL_BOOKE) */
312#if defined(CONFIG_SMP)
313	rlwinm	r8,r1,0,0,(31-THREAD_SHIFT)
314	lwz	r8,TI_CPU(r8)
315	oris	r8,r8,10
316	mfmsr	r10
317	SYNC
318	rlwinm	r0,r10,0,17,15		/* clear bit 16 (MSR_EE) */
319	rlwinm	r0,r0,0,28,26		/* clear DR */
320	mtmsr	r0
321	SYNC_601
322	isync
323	lis	r9,mmu_hash_lock@h
324	ori	r9,r9,mmu_hash_lock@l
325	tophys(r9,r9)
32610:	lwarx	r7,0,r9
327	cmpwi	0,r7,0
328	bne-	10b
329	stwcx.	r8,0,r9
330	bne-	10b
331	sync
332	tlbia
333	sync
334	TLBSYNC
335	li	r0,0
336	stw	r0,0(r9)		/* clear mmu_hash_lock */
337	mtmsr	r10
338	SYNC_601
339	isync
340#else /* CONFIG_SMP */
341	sync
342	tlbia
343	sync
344#endif /* CONFIG_SMP */
345#endif /* ! defined(CONFIG_40x) */
346	blr
347
348/*
349 * Flush MMU TLB for a particular address
350 */
351#ifndef CONFIG_FSL_BOOKE
352_GLOBAL(_tlbil_va)
353#endif
354_GLOBAL(_tlbie)
355#if defined(CONFIG_40x)
356	/* We run the search with interrupts disabled because we have to change
357	 * the PID and I don't want to preempt when that happens.
358	 */
359	mfmsr	r5
360	mfspr	r6,SPRN_PID
361	wrteei	0
362	mtspr	SPRN_PID,r4
363	tlbsx.	r3, 0, r3
364	mtspr	SPRN_PID,r6
365	wrtee	r5
366	bne	10f
367	sync
368	/* There are only 64 TLB entries, so r3 < 64, which means bit 25 is clear.
369	 * Since 25 is the V bit in the TLB_TAG, loading this value will invalidate
370	 * the TLB entry. */
371	tlbwe	r3, r3, TLB_TAG
372	isync
37310:
374
375#elif defined(CONFIG_44x)
376	mfspr	r5,SPRN_MMUCR
377	rlwimi	r5,r4,0,24,31			/* Set TID */
378
379	/* We have to run the search with interrupts disabled, even critical
380	 * and debug interrupts (in fact the only critical exceptions we have
381	 * are debug and machine check).  Otherwise  an interrupt which causes
382	 * a TLB miss can clobber the MMUCR between the mtspr and the tlbsx. */
383	mfmsr	r4
384	lis	r6,(MSR_EE|MSR_CE|MSR_ME|MSR_DE)@ha
385	addi	r6,r6,(MSR_EE|MSR_CE|MSR_ME|MSR_DE)@l
386	andc	r6,r4,r6
387	mtmsr	r6
388	mtspr	SPRN_MMUCR,r5
389	tlbsx.	r3, 0, r3
390	mtmsr	r4
391	bne	10f
392	sync
393	/* There are only 64 TLB entries, so r3 < 64,
394	 * which means bit 22, is clear.  Since 22 is
395	 * the V bit in the TLB_PAGEID, loading this
396	 * value will invalidate the TLB entry.
397	 */
398	tlbwe	r3, r3, PPC44x_TLB_PAGEID
399	isync
40010:
401#elif defined(CONFIG_FSL_BOOKE)
402	rlwinm	r4, r3, 0, 0, 19
403	ori	r5, r4, 0x08	/* TLBSEL = 1 */
404	tlbivax	0, r4
405	tlbivax	0, r5
406	msync
407#if defined(CONFIG_SMP)
408	tlbsync
409#endif /* CONFIG_SMP */
410#else /* !(CONFIG_40x || CONFIG_44x || CONFIG_FSL_BOOKE) */
411#if defined(CONFIG_SMP)
412	rlwinm	r8,r1,0,0,(31-THREAD_SHIFT)
413	lwz	r8,TI_CPU(r8)
414	oris	r8,r8,11
415	mfmsr	r10
416	SYNC
417	rlwinm	r0,r10,0,17,15		/* clear bit 16 (MSR_EE) */
418	rlwinm	r0,r0,0,28,26		/* clear DR */
419	mtmsr	r0
420	SYNC_601
421	isync
422	lis	r9,mmu_hash_lock@h
423	ori	r9,r9,mmu_hash_lock@l
424	tophys(r9,r9)
42510:	lwarx	r7,0,r9
426	cmpwi	0,r7,0
427	bne-	10b
428	stwcx.	r8,0,r9
429	bne-	10b
430	eieio
431	tlbie	r3
432	sync
433	TLBSYNC
434	li	r0,0
435	stw	r0,0(r9)		/* clear mmu_hash_lock */
436	mtmsr	r10
437	SYNC_601
438	isync
439#else /* CONFIG_SMP */
440	tlbie	r3
441	sync
442#endif /* CONFIG_SMP */
443#endif /* ! CONFIG_40x */
444	blr
445
446#if defined(CONFIG_FSL_BOOKE)
447/*
448 * Flush MMU TLB, but only on the local processor (no broadcast)
449 */
450_GLOBAL(_tlbil_all)
451#define MMUCSR0_TLBFI	(MMUCSR0_TLB0FI | MMUCSR0_TLB1FI | \
452			 MMUCSR0_TLB2FI | MMUCSR0_TLB3FI)
453	li	r3,(MMUCSR0_TLBFI)@l
454	mtspr	SPRN_MMUCSR0, r3
4551:
456	mfspr	r3,SPRN_MMUCSR0
457	andi.	r3,r3,MMUCSR0_TLBFI@l
458	bne	1b
459	blr
460
461/*
462 * Flush MMU TLB for a particular process id, but only on the local processor
463 * (no broadcast)
464 */
465_GLOBAL(_tlbil_pid)
466/* we currently do an invalidate all since we don't have per pid invalidate */
467	li	r3,(MMUCSR0_TLBFI)@l
468	mtspr	SPRN_MMUCSR0, r3
4691:
470	mfspr	r3,SPRN_MMUCSR0
471	andi.	r3,r3,MMUCSR0_TLBFI@l
472	bne	1b
473	msync
474	isync
475	blr
476
477/*
478 * Flush MMU TLB for a particular address, but only on the local processor
479 * (no broadcast)
480 */
481_GLOBAL(_tlbil_va)
482	mfmsr	r10
483	wrteei	0
484	slwi	r4,r4,16
485	mtspr	SPRN_MAS6,r4		/* assume AS=0 for now */
486	tlbsx	0,r3
487	mfspr	r4,SPRN_MAS1		/* check valid */
488	andis.	r3,r4,MAS1_VALID@h
489	beqlr
490	rlwinm	r4,r4,0,1,31
491	mtspr	SPRN_MAS1,r4
492	tlbwe
493	msync
494	isync
495	wrtee	r10
496	blr
497#endif /* CONFIG_FSL_BOOKE */
498
499
500/*
501 * Flush instruction cache.
502 * This is a no-op on the 601.
503 */
504_GLOBAL(flush_instruction_cache)
505#if defined(CONFIG_8xx)
506	isync
507	lis	r5, IDC_INVALL@h
508	mtspr	SPRN_IC_CST, r5
509#elif defined(CONFIG_4xx)
510#ifdef CONFIG_403GCX
511	li      r3, 512
512	mtctr   r3
513	lis     r4, KERNELBASE@h
5141:	iccci   0, r4
515	addi    r4, r4, 16
516	bdnz    1b
517#else
518	lis	r3, KERNELBASE@h
519	iccci	0,r3
520#endif
521#elif CONFIG_FSL_BOOKE
522BEGIN_FTR_SECTION
523	mfspr   r3,SPRN_L1CSR0
524	ori     r3,r3,L1CSR0_CFI|L1CSR0_CLFC
525	/* msync; isync recommended here */
526	mtspr   SPRN_L1CSR0,r3
527	isync
528	blr
529END_FTR_SECTION_IFSET(CPU_FTR_UNIFIED_ID_CACHE)
530	mfspr	r3,SPRN_L1CSR1
531	ori	r3,r3,L1CSR1_ICFI|L1CSR1_ICLFR
532	mtspr	SPRN_L1CSR1,r3
533#else
534	mfspr	r3,SPRN_PVR
535	rlwinm	r3,r3,16,16,31
536	cmpwi	0,r3,1
537	beqlr			/* for 601, do nothing */
538	/* 603/604 processor - use invalidate-all bit in HID0 */
539	mfspr	r3,SPRN_HID0
540	ori	r3,r3,HID0_ICFI
541	mtspr	SPRN_HID0,r3
542#endif /* CONFIG_8xx/4xx */
543	isync
544	blr
545
546/*
547 * Write any modified data cache blocks out to memory
548 * and invalidate the corresponding instruction cache blocks.
549 * This is a no-op on the 601.
550 *
551 * flush_icache_range(unsigned long start, unsigned long stop)
552 */
553_KPROBE(__flush_icache_range)
554BEGIN_FTR_SECTION
555	blr				/* for 601, do nothing */
556END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
557	li	r5,L1_CACHE_BYTES-1
558	andc	r3,r3,r5
559	subf	r4,r3,r4
560	add	r4,r4,r5
561	srwi.	r4,r4,L1_CACHE_SHIFT
562	beqlr
563	mtctr	r4
564	mr	r6,r3
5651:	dcbst	0,r3
566	addi	r3,r3,L1_CACHE_BYTES
567	bdnz	1b
568	sync				/* wait for dcbst's to get to ram */
569	mtctr	r4
5702:	icbi	0,r6
571	addi	r6,r6,L1_CACHE_BYTES
572	bdnz	2b
573	sync				/* additional sync needed on g4 */
574	isync
575	blr
576/*
577 * Write any modified data cache blocks out to memory.
578 * Does not invalidate the corresponding cache lines (especially for
579 * any corresponding instruction cache).
580 *
581 * clean_dcache_range(unsigned long start, unsigned long stop)
582 */
583_GLOBAL(clean_dcache_range)
584	li	r5,L1_CACHE_BYTES-1
585	andc	r3,r3,r5
586	subf	r4,r3,r4
587	add	r4,r4,r5
588	srwi.	r4,r4,L1_CACHE_SHIFT
589	beqlr
590	mtctr	r4
591
5921:	dcbst	0,r3
593	addi	r3,r3,L1_CACHE_BYTES
594	bdnz	1b
595	sync				/* wait for dcbst's to get to ram */
596	blr
597
598/*
599 * Write any modified data cache blocks out to memory and invalidate them.
600 * Does not invalidate the corresponding instruction cache blocks.
601 *
602 * flush_dcache_range(unsigned long start, unsigned long stop)
603 */
604_GLOBAL(flush_dcache_range)
605	li	r5,L1_CACHE_BYTES-1
606	andc	r3,r3,r5
607	subf	r4,r3,r4
608	add	r4,r4,r5
609	srwi.	r4,r4,L1_CACHE_SHIFT
610	beqlr
611	mtctr	r4
612
6131:	dcbf	0,r3
614	addi	r3,r3,L1_CACHE_BYTES
615	bdnz	1b
616	sync				/* wait for dcbst's to get to ram */
617	blr
618
619/*
620 * Like above, but invalidate the D-cache.  This is used by the 8xx
621 * to invalidate the cache so the PPC core doesn't get stale data
622 * from the CPM (no cache snooping here :-).
623 *
624 * invalidate_dcache_range(unsigned long start, unsigned long stop)
625 */
626_GLOBAL(invalidate_dcache_range)
627	li	r5,L1_CACHE_BYTES-1
628	andc	r3,r3,r5
629	subf	r4,r3,r4
630	add	r4,r4,r5
631	srwi.	r4,r4,L1_CACHE_SHIFT
632	beqlr
633	mtctr	r4
634
6351:	dcbi	0,r3
636	addi	r3,r3,L1_CACHE_BYTES
637	bdnz	1b
638	sync				/* wait for dcbi's to get to ram */
639	blr
640
641/*
642 * Flush a particular page from the data cache to RAM.
643 * Note: this is necessary because the instruction cache does *not*
644 * snoop from the data cache.
645 * This is a no-op on the 601 which has a unified cache.
646 *
647 *	void __flush_dcache_icache(void *page)
648 */
649_GLOBAL(__flush_dcache_icache)
650BEGIN_FTR_SECTION
651	blr
652END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
653	rlwinm	r3,r3,0,0,19			/* Get page base address */
654	li	r4,4096/L1_CACHE_BYTES	/* Number of lines in a page */
655	mtctr	r4
656	mr	r6,r3
6570:	dcbst	0,r3				/* Write line to ram */
658	addi	r3,r3,L1_CACHE_BYTES
659	bdnz	0b
660	sync
661#ifndef CONFIG_44x
662	/* We don't flush the icache on 44x. Those have a virtual icache
663	 * and we don't have access to the virtual address here (it's
664	 * not the page vaddr but where it's mapped in user space). The
665	 * flushing of the icache on these is handled elsewhere, when
666	 * a change in the address space occurs, before returning to
667	 * user space
668	 */
669	mtctr	r4
6701:	icbi	0,r6
671	addi	r6,r6,L1_CACHE_BYTES
672	bdnz	1b
673	sync
674	isync
675#endif /* CONFIG_44x */
676	blr
677
678/*
679 * Flush a particular page from the data cache to RAM, identified
680 * by its physical address.  We turn off the MMU so we can just use
681 * the physical address (this may be a highmem page without a kernel
682 * mapping).
683 *
684 *	void __flush_dcache_icache_phys(unsigned long physaddr)
685 */
686_GLOBAL(__flush_dcache_icache_phys)
687BEGIN_FTR_SECTION
688	blr					/* for 601, do nothing */
689END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
690	mfmsr	r10
691	rlwinm	r0,r10,0,28,26			/* clear DR */
692	mtmsr	r0
693	isync
694	rlwinm	r3,r3,0,0,19			/* Get page base address */
695	li	r4,4096/L1_CACHE_BYTES	/* Number of lines in a page */
696	mtctr	r4
697	mr	r6,r3
6980:	dcbst	0,r3				/* Write line to ram */
699	addi	r3,r3,L1_CACHE_BYTES
700	bdnz	0b
701	sync
702	mtctr	r4
7031:	icbi	0,r6
704	addi	r6,r6,L1_CACHE_BYTES
705	bdnz	1b
706	sync
707	mtmsr	r10				/* restore DR */
708	isync
709	blr
710
711/*
712 * Clear pages using the dcbz instruction, which doesn't cause any
713 * memory traffic (except to write out any cache lines which get
714 * displaced).  This only works on cacheable memory.
715 *
716 * void clear_pages(void *page, int order) ;
717 */
718_GLOBAL(clear_pages)
719	li	r0,4096/L1_CACHE_BYTES
720	slw	r0,r0,r4
721	mtctr	r0
722#ifdef CONFIG_8xx
723	li	r4, 0
7241:	stw	r4, 0(r3)
725	stw	r4, 4(r3)
726	stw	r4, 8(r3)
727	stw	r4, 12(r3)
728#else
7291:	dcbz	0,r3
730#endif
731	addi	r3,r3,L1_CACHE_BYTES
732	bdnz	1b
733	blr
734
735/*
736 * Copy a whole page.  We use the dcbz instruction on the destination
737 * to reduce memory traffic (it eliminates the unnecessary reads of
738 * the destination into cache).  This requires that the destination
739 * is cacheable.
740 */
741#define COPY_16_BYTES		\
742	lwz	r6,4(r4);	\
743	lwz	r7,8(r4);	\
744	lwz	r8,12(r4);	\
745	lwzu	r9,16(r4);	\
746	stw	r6,4(r3);	\
747	stw	r7,8(r3);	\
748	stw	r8,12(r3);	\
749	stwu	r9,16(r3)
750
751_GLOBAL(copy_page)
752	addi	r3,r3,-4
753	addi	r4,r4,-4
754
755#ifdef CONFIG_8xx
756	/* don't use prefetch on 8xx */
757    	li	r0,4096/L1_CACHE_BYTES
758	mtctr	r0
7591:	COPY_16_BYTES
760	bdnz	1b
761	blr
762
763#else	/* not 8xx, we can prefetch */
764	li	r5,4
765
766#if MAX_COPY_PREFETCH > 1
767	li	r0,MAX_COPY_PREFETCH
768	li	r11,4
769	mtctr	r0
77011:	dcbt	r11,r4
771	addi	r11,r11,L1_CACHE_BYTES
772	bdnz	11b
773#else /* MAX_COPY_PREFETCH == 1 */
774	dcbt	r5,r4
775	li	r11,L1_CACHE_BYTES+4
776#endif /* MAX_COPY_PREFETCH */
777	li	r0,4096/L1_CACHE_BYTES - MAX_COPY_PREFETCH
778	crclr	4*cr0+eq
7792:
780	mtctr	r0
7811:
782	dcbt	r11,r4
783	dcbz	r5,r3
784	COPY_16_BYTES
785#if L1_CACHE_BYTES >= 32
786	COPY_16_BYTES
787#if L1_CACHE_BYTES >= 64
788	COPY_16_BYTES
789	COPY_16_BYTES
790#if L1_CACHE_BYTES >= 128
791	COPY_16_BYTES
792	COPY_16_BYTES
793	COPY_16_BYTES
794	COPY_16_BYTES
795#endif
796#endif
797#endif
798	bdnz	1b
799	beqlr
800	crnot	4*cr0+eq,4*cr0+eq
801	li	r0,MAX_COPY_PREFETCH
802	li	r11,4
803	b	2b
804#endif	/* CONFIG_8xx */
805
806/*
807 * void atomic_clear_mask(atomic_t mask, atomic_t *addr)
808 * void atomic_set_mask(atomic_t mask, atomic_t *addr);
809 */
810_GLOBAL(atomic_clear_mask)
81110:	lwarx	r5,0,r4
812	andc	r5,r5,r3
813	PPC405_ERR77(0,r4)
814	stwcx.	r5,0,r4
815	bne-	10b
816	blr
817_GLOBAL(atomic_set_mask)
81810:	lwarx	r5,0,r4
819	or	r5,r5,r3
820	PPC405_ERR77(0,r4)
821	stwcx.	r5,0,r4
822	bne-	10b
823	blr
824
825/*
826 * Extended precision shifts.
827 *
828 * Updated to be valid for shift counts from 0 to 63 inclusive.
829 * -- Gabriel
830 *
831 * R3/R4 has 64 bit value
832 * R5    has shift count
833 * result in R3/R4
834 *
835 *  ashrdi3: arithmetic right shift (sign propagation)
836 *  lshrdi3: logical right shift
837 *  ashldi3: left shift
838 */
839_GLOBAL(__ashrdi3)
840	subfic	r6,r5,32
841	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
842	addi	r7,r5,32	# could be xori, or addi with -32
843	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
844	rlwinm	r8,r7,0,32	# t3 = (count < 32) ? 32 : 0
845	sraw	r7,r3,r7	# t2 = MSW >> (count-32)
846	or	r4,r4,r6	# LSW |= t1
847	slw	r7,r7,r8	# t2 = (count < 32) ? 0 : t2
848	sraw	r3,r3,r5	# MSW = MSW >> count
849	or	r4,r4,r7	# LSW |= t2
850	blr
851
852_GLOBAL(__ashldi3)
853	subfic	r6,r5,32
854	slw	r3,r3,r5	# MSW = count > 31 ? 0 : MSW << count
855	addi	r7,r5,32	# could be xori, or addi with -32
856	srw	r6,r4,r6	# t1 = count > 31 ? 0 : LSW >> (32-count)
857	slw	r7,r4,r7	# t2 = count < 32 ? 0 : LSW << (count-32)
858	or	r3,r3,r6	# MSW |= t1
859	slw	r4,r4,r5	# LSW = LSW << count
860	or	r3,r3,r7	# MSW |= t2
861	blr
862
863_GLOBAL(__lshrdi3)
864	subfic	r6,r5,32
865	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
866	addi	r7,r5,32	# could be xori, or addi with -32
867	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
868	srw	r7,r3,r7	# t2 = count < 32 ? 0 : MSW >> (count-32)
869	or	r4,r4,r6	# LSW |= t1
870	srw	r3,r3,r5	# MSW = MSW >> count
871	or	r4,r4,r7	# LSW |= t2
872	blr
873
874/*
875 * 64-bit comparison: __ucmpdi2(u64 a, u64 b)
876 * Returns 0 if a < b, 1 if a == b, 2 if a > b.
877 */
878_GLOBAL(__ucmpdi2)
879	cmplw	r3,r5
880	li	r3,1
881	bne	1f
882	cmplw	r4,r6
883	beqlr
8841:	li	r3,0
885	bltlr
886	li	r3,2
887	blr
888
889_GLOBAL(abs)
890	srawi	r4,r3,31
891	xor	r3,r3,r4
892	sub	r3,r3,r4
893	blr
894
895/*
896 * Create a kernel thread
897 *   kernel_thread(fn, arg, flags)
898 */
899_GLOBAL(kernel_thread)
900	stwu	r1,-16(r1)
901	stw	r30,8(r1)
902	stw	r31,12(r1)
903	mr	r30,r3		/* function */
904	mr	r31,r4		/* argument */
905	ori	r3,r5,CLONE_VM	/* flags */
906	oris	r3,r3,CLONE_UNTRACED>>16
907	li	r4,0		/* new sp (unused) */
908	li	r0,__NR_clone
909	sc
910	bns+	1f		/* did system call indicate error? */
911	neg	r3,r3		/* if so, make return code negative */
9121:	cmpwi	0,r3,0		/* parent or child? */
913	bne	2f		/* return if parent */
914	li	r0,0		/* make top-level stack frame */
915	stwu	r0,-16(r1)
916	mtlr	r30		/* fn addr in lr */
917	mr	r3,r31		/* load arg and call fn */
918	PPC440EP_ERR42
919	blrl
920	li	r0,__NR_exit	/* exit if function returns */
921	li	r3,0
922	sc
9232:	lwz	r30,8(r1)
924	lwz	r31,12(r1)
925	addi	r1,r1,16
926	blr
927
928/*
929 * This routine is just here to keep GCC happy - sigh...
930 */
931_GLOBAL(__main)
932	blr
933
934#ifdef CONFIG_KEXEC
935	/*
936	 * Must be relocatable PIC code callable as a C function.
937	 */
938	.globl relocate_new_kernel
939relocate_new_kernel:
940	/* r3 = page_list   */
941	/* r4 = reboot_code_buffer */
942	/* r5 = start_address      */
943
944	li	r0, 0
945
946	/*
947	 * Set Machine Status Register to a known status,
948	 * switch the MMU off and jump to 1: in a single step.
949	 */
950
951	mr	r8, r0
952	ori     r8, r8, MSR_RI|MSR_ME
953	mtspr	SPRN_SRR1, r8
954	addi	r8, r4, 1f - relocate_new_kernel
955	mtspr	SPRN_SRR0, r8
956	sync
957	rfi
958
9591:
960	/* from this point address translation is turned off */
961	/* and interrupts are disabled */
962
963	/* set a new stack at the bottom of our page... */
964	/* (not really needed now) */
965	addi	r1, r4, KEXEC_CONTROL_PAGE_SIZE - 8 /* for LR Save+Back Chain */
966	stw	r0, 0(r1)
967
968	/* Do the copies */
969	li	r6, 0 /* checksum */
970	mr	r0, r3
971	b	1f
972
9730:	/* top, read another word for the indirection page */
974	lwzu	r0, 4(r3)
975
9761:
977	/* is it a destination page? (r8) */
978	rlwinm.	r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
979	beq	2f
980
981	rlwinm	r8, r0, 0, 0, 19 /* clear kexec flags, page align */
982	b	0b
983
9842:	/* is it an indirection page? (r3) */
985	rlwinm.	r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
986	beq	2f
987
988	rlwinm	r3, r0, 0, 0, 19 /* clear kexec flags, page align */
989	subi	r3, r3, 4
990	b	0b
991
9922:	/* are we done? */
993	rlwinm.	r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
994	beq	2f
995	b	3f
996
9972:	/* is it a source page? (r9) */
998	rlwinm.	r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
999	beq	0b
1000
1001	rlwinm	r9, r0, 0, 0, 19 /* clear kexec flags, page align */
1002
1003	li	r7, PAGE_SIZE / 4
1004	mtctr   r7
1005	subi    r9, r9, 4
1006	subi    r8, r8, 4
10079:
1008	lwzu    r0, 4(r9)  /* do the copy */
1009	xor	r6, r6, r0
1010	stwu    r0, 4(r8)
1011	dcbst	0, r8
1012	sync
1013	icbi	0, r8
1014	bdnz    9b
1015
1016	addi    r9, r9, 4
1017	addi    r8, r8, 4
1018	b	0b
1019
10203:
1021
1022	/* To be certain of avoiding problems with self-modifying code
1023	 * execute a serializing instruction here.
1024	 */
1025	isync
1026	sync
1027
1028	/* jump to the entry point, usually the setup routine */
1029	mtlr	r5
1030	blrl
1031
10321:	b	1b
1033
1034relocate_new_kernel_end:
1035
1036	.globl relocate_new_kernel_size
1037relocate_new_kernel_size:
1038	.long relocate_new_kernel_end - relocate_new_kernel
1039#endif
1040