| blob | 5c2e253ddfb1a8eec7efbc582a8017724def45bb |
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 */
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>
33 .text
35 /*
36 * This returns the high 64 bits of the product of two 64-bit numbers.
37 */
38 _GLOBAL(mulhdu)
39 cmpwi r6,0
40 cmpwi cr1,r3,0
41 mr r10,r4
42 mulhwu r4,r4,r5
43 beq 1f
44 mulhwu r0,r10,r6
45 mullw r7,r10,r5
46 addc r7,r0,r7
47 addze r4,r4
48 1: beqlr cr1 /* all done if high part of A is 0 */
49 mr r10,r3
50 mullw r9,r3,r5
51 mulhwu r3,r3,r5
52 beq 2f
53 mullw r0,r10,r6
54 mulhwu r8,r10,r6
55 addc r7,r0,r7
56 adde r4,r4,r8
57 addze r3,r3
58 2: addc r4,r4,r9
59 addze r3,r3
60 blr
62 /*
63 * sub_reloc_offset(x) returns x - reloc_offset().
64 */
65 _GLOBAL(sub_reloc_offset)
66 mflr r0
67 bl 1f
68 1: mflr r5
69 lis r4,1b@ha
70 addi r4,r4,1b@l
71 subf r5,r4,r5
72 subf r3,r5,r3
73 mtlr r0
74 blr
76 /*
77 * reloc_got2 runs through the .got2 section adding an offset
78 * to each entry.
79 */
80 _GLOBAL(reloc_got2)
81 mflr r11
82 lis r7,__got2_start@ha
83 addi r7,r7,__got2_start@l
84 lis r8,__got2_end@ha
85 addi r8,r8,__got2_end@l
86 subf r8,r7,r8
87 srwi. r8,r8,2
88 beqlr
89 mtctr r8
90 bl 1f
91 1: mflr r0
92 lis r4,1b@ha
93 addi r4,r4,1b@l
94 subf r0,r4,r0
95 add r7,r0,r7
96 2: lwz r0,0(r7)
97 add r0,r0,r3
98 stw r0,0(r7)
99 addi r7,r7,4
100 bdnz 2b
101 mtlr r11
102 blr
104 /*
105 * call_setup_cpu - call the setup_cpu function for this cpu
106 * r3 = data offset, r24 = cpu number
107 *
108 * Setup function is called with:
109 * r3 = data offset
110 * r4 = ptr to CPU spec (relocated)
111 */
112 _GLOBAL(call_setup_cpu)
113 addis r4,r3,cur_cpu_spec@ha
114 addi r4,r4,cur_cpu_spec@l
115 lwz r4,0(r4)
116 add r4,r4,r3
117 lwz r5,CPU_SPEC_SETUP(r4)
118 cmpwi 0,r5,0
119 add r5,r5,r3
120 beqlr
121 mtctr r5
122 bctr
124 #if defined(CONFIG_CPU_FREQ_PMAC) && defined(CONFIG_6xx)
126 /* This gets called by via-pmu.c to switch the PLL selection
127 * on 750fx CPU. This function should really be moved to some
128 * other place (as most of the cpufreq code in via-pmu
129 */
130 _GLOBAL(low_choose_750fx_pll)
131 /* Clear MSR:EE */
132 mfmsr r7
133 rlwinm r0,r7,0,17,15
134 mtmsr r0
136 /* If switching to PLL1, disable HID0:BTIC */
137 cmplwi cr0,r3,0
138 beq 1f
139 mfspr r5,SPRN_HID0
140 rlwinm r5,r5,0,27,25
141 sync
142 mtspr SPRN_HID0,r5
143 isync
144 sync
146 1:
147 /* Calc new HID1 value */
148 mfspr r4,SPRN_HID1 /* Build a HID1:PS bit from parameter */
149 rlwinm r5,r3,16,15,15 /* Clear out HID1:PS from value read */
150 rlwinm r4,r4,0,16,14 /* Could have I used rlwimi here ? */
151 or r4,r4,r5
152 mtspr SPRN_HID1,r4
154 /* Store new HID1 image */
155 rlwinm r6,r1,0,0,18
156 lwz r6,TI_CPU(r6)
157 slwi r6,r6,2
158 addis r6,r6,nap_save_hid1@ha
159 stw r4,nap_save_hid1@l(r6)
161 /* If switching to PLL0, enable HID0:BTIC */
162 cmplwi cr0,r3,0
163 bne 1f
164 mfspr r5,SPRN_HID0
165 ori r5,r5,HID0_BTIC
166 sync
167 mtspr SPRN_HID0,r5
168 isync
169 sync
171 1:
172 /* Return */
173 mtmsr r7
174 blr
176 _GLOBAL(low_choose_7447a_dfs)
177 /* Clear MSR:EE */
178 mfmsr r7
179 rlwinm r0,r7,0,17,15
180 mtmsr r0
182 /* Calc new HID1 value */
183 mfspr r4,SPRN_HID1
184 insrwi r4,r3,1,9 /* insert parameter into bit 9 */
185 sync
186 mtspr SPRN_HID1,r4
187 sync
188 isync
190 /* Return */
191 mtmsr r7
192 blr
194 #endif /* CONFIG_CPU_FREQ_PMAC && CONFIG_6xx */
196 /*
197 * complement mask on the msr then "or" some values on.
198 * _nmask_and_or_msr(nmask, value_to_or)
199 */
200 _GLOBAL(_nmask_and_or_msr)
201 mfmsr r0 /* Get current msr */
202 andc r0,r0,r3 /* And off the bits set in r3 (first parm) */
203 or r0,r0,r4 /* Or on the bits in r4 (second parm) */
204 SYNC /* Some chip revs have problems here... */
205 mtmsr r0 /* Update machine state */
206 isync
207 blr /* Done */
209 #ifdef CONFIG_40x
211 /*
212 * Do an IO access in real mode
213 */
214 _GLOBAL(real_readb)
215 mfmsr r7
216 ori r0,r7,MSR_DR
217 xori r0,r0,MSR_DR
218 sync
219 mtmsr r0
220 sync
221 isync
222 lbz r3,0(r3)
223 sync
224 mtmsr r7
225 sync
226 isync
227 blr
229 /*
230 * Do an IO access in real mode
231 */
232 _GLOBAL(real_writeb)
233 mfmsr r7
234 ori r0,r7,MSR_DR
235 xori r0,r0,MSR_DR
236 sync
237 mtmsr r0
238 sync
239 isync
240 stb r3,0(r4)
241 sync
242 mtmsr r7
243 sync
244 isync
245 blr
247 #endif /* CONFIG_40x */
249 /*
250 * Flush MMU TLB
251 */
252 _GLOBAL(_tlbia)
253 #if defined(CONFIG_40x)
254 sync /* Flush to memory before changing mapping */
255 tlbia
256 isync /* Flush shadow TLB */
257 #elif defined(CONFIG_44x)
258 li r3,0
259 sync
261 /* Load high watermark */
262 lis r4,tlb_44x_hwater@ha
263 lwz r5,tlb_44x_hwater@l(r4)
265 1: tlbwe r3,r3,PPC44x_TLB_PAGEID
266 addi r3,r3,1
267 cmpw 0,r3,r5
268 ble 1b
270 isync
271 #elif defined(CONFIG_FSL_BOOKE)
272 /* Invalidate all entries in TLB0 */
273 li r3, 0x04
274 tlbivax 0,3
275 /* Invalidate all entries in TLB1 */
276 li r3, 0x0c
277 tlbivax 0,3
278 msync
279 #ifdef CONFIG_SMP
280 tlbsync
281 #endif /* CONFIG_SMP */
282 #else /* !(CONFIG_40x || CONFIG_44x || CONFIG_FSL_BOOKE) */
283 #if defined(CONFIG_SMP)
284 rlwinm r8,r1,0,0,18
285 lwz r8,TI_CPU(r8)
286 oris r8,r8,10
287 mfmsr r10
288 SYNC
289 rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */
290 rlwinm r0,r0,0,28,26 /* clear DR */
291 mtmsr r0
292 SYNC_601
293 isync
294 lis r9,mmu_hash_lock@h
295 ori r9,r9,mmu_hash_lock@l
296 tophys(r9,r9)
297 10: lwarx r7,0,r9
298 cmpwi 0,r7,0
299 bne- 10b
300 stwcx. r8,0,r9
301 bne- 10b
302 sync
303 tlbia
304 sync
305 TLBSYNC
306 li r0,0
307 stw r0,0(r9) /* clear mmu_hash_lock */
308 mtmsr r10
309 SYNC_601
310 isync
311 #else /* CONFIG_SMP */
312 sync
313 tlbia
314 sync
315 #endif /* CONFIG_SMP */
316 #endif /* ! defined(CONFIG_40x) */
317 blr
319 /*
320 * Flush MMU TLB for a particular address
321 */
322 _GLOBAL(_tlbie)
323 #if defined(CONFIG_40x)
324 /* We run the search with interrupts disabled because we have to change
325 * the PID and I don't want to preempt when that happens.
326 */
327 mfmsr r5
328 mfspr r6,SPRN_PID
329 wrteei 0
330 mtspr SPRN_PID,r4
331 tlbsx. r3, 0, r3
332 mtspr SPRN_PID,r6
333 wrtee r5
334 bne 10f
335 sync
336 /* There are only 64 TLB entries, so r3 < 64, which means bit 25 is clear.
337 * Since 25 is the V bit in the TLB_TAG, loading this value will invalidate
338 * the TLB entry. */
339 tlbwe r3, r3, TLB_TAG
340 isync
341 10:
343 #elif defined(CONFIG_44x)
344 mfspr r5,SPRN_MMUCR
345 rlwimi r5,r4,0,24,31 /* Set TID */
347 /* We have to run the search with interrupts disabled, even critical
348 * and debug interrupts (in fact the only critical exceptions we have
349 * are debug and machine check). Otherwise an interrupt which causes
350 * a TLB miss can clobber the MMUCR between the mtspr and the tlbsx. */
351 mfmsr r4
352 lis r6,(MSR_EE|MSR_CE|MSR_ME|MSR_DE)@ha
353 addi r6,r6,(MSR_EE|MSR_CE|MSR_ME|MSR_DE)@l
354 andc r6,r4,r6
355 mtmsr r6
356 mtspr SPRN_MMUCR,r5
357 tlbsx. r3, 0, r3
358 mtmsr r4
359 bne 10f
360 sync
361 /* There are only 64 TLB entries, so r3 < 64,
362 * which means bit 22, is clear. Since 22 is
363 * the V bit in the TLB_PAGEID, loading this
364 * value will invalidate the TLB entry.
365 */
366 tlbwe r3, r3, PPC44x_TLB_PAGEID
367 isync
368 10:
369 #elif defined(CONFIG_FSL_BOOKE)
370 rlwinm r4, r3, 0, 0, 19
371 ori r5, r4, 0x08 /* TLBSEL = 1 */
372 tlbivax 0, r4
373 tlbivax 0, r5
374 msync
375 #if defined(CONFIG_SMP)
376 tlbsync
377 #endif /* CONFIG_SMP */
378 #else /* !(CONFIG_40x || CONFIG_44x || CONFIG_FSL_BOOKE) */
379 #if defined(CONFIG_SMP)
380 rlwinm r8,r1,0,0,18
381 lwz r8,TI_CPU(r8)
382 oris r8,r8,11
383 mfmsr r10
384 SYNC
385 rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */
386 rlwinm r0,r0,0,28,26 /* clear DR */
387 mtmsr r0
388 SYNC_601
389 isync
390 lis r9,mmu_hash_lock@h
391 ori r9,r9,mmu_hash_lock@l
392 tophys(r9,r9)
393 10: lwarx r7,0,r9
394 cmpwi 0,r7,0
395 bne- 10b
396 stwcx. r8,0,r9
397 bne- 10b
398 eieio
399 tlbie r3
400 sync
401 TLBSYNC
402 li r0,0
403 stw r0,0(r9) /* clear mmu_hash_lock */
404 mtmsr r10
405 SYNC_601
406 isync
407 #else /* CONFIG_SMP */
408 tlbie r3
409 sync
410 #endif /* CONFIG_SMP */
411 #endif /* ! CONFIG_40x */
412 blr
414 /*
415 * Flush instruction cache.
416 * This is a no-op on the 601.
417 */
418 _GLOBAL(flush_instruction_cache)
419 #if defined(CONFIG_8xx)
420 isync
421 lis r5, IDC_INVALL@h
422 mtspr SPRN_IC_CST, r5
423 #elif defined(CONFIG_4xx)
424 #ifdef CONFIG_403GCX
425 li r3, 512
426 mtctr r3
427 lis r4, KERNELBASE@h
428 1: iccci 0, r4
429 addi r4, r4, 16
430 bdnz 1b
431 #else
432 lis r3, KERNELBASE@h
433 iccci 0,r3
434 #endif
435 #elif CONFIG_FSL_BOOKE
436 BEGIN_FTR_SECTION
437 mfspr r3,SPRN_L1CSR0
438 ori r3,r3,L1CSR0_CFI|L1CSR0_CLFC
439 /* msync; isync recommended here */
440 mtspr SPRN_L1CSR0,r3
441 isync
442 blr
443 END_FTR_SECTION_IFSET(CPU_FTR_UNIFIED_ID_CACHE)
444 mfspr r3,SPRN_L1CSR1
445 ori r3,r3,L1CSR1_ICFI|L1CSR1_ICLFR
446 mtspr SPRN_L1CSR1,r3
447 #else
448 mfspr r3,SPRN_PVR
449 rlwinm r3,r3,16,16,31
450 cmpwi 0,r3,1
451 beqlr /* for 601, do nothing */
452 /* 603/604 processor - use invalidate-all bit in HID0 */
453 mfspr r3,SPRN_HID0
454 ori r3,r3,HID0_ICFI
455 mtspr SPRN_HID0,r3
456 #endif /* CONFIG_8xx/4xx */
457 isync
458 blr
460 /*
461 * Write any modified data cache blocks out to memory
462 * and invalidate the corresponding instruction cache blocks.
463 * This is a no-op on the 601.
464 *
465 * flush_icache_range(unsigned long start, unsigned long stop)
466 */
467 _GLOBAL(__flush_icache_range)
468 BEGIN_FTR_SECTION
469 blr /* for 601, do nothing */
470 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
471 li r5,L1_CACHE_BYTES-1
472 andc r3,r3,r5
473 subf r4,r3,r4
474 add r4,r4,r5
475 srwi. r4,r4,L1_CACHE_SHIFT
476 beqlr
477 mtctr r4
478 mr r6,r3
479 1: dcbst 0,r3
480 addi r3,r3,L1_CACHE_BYTES
481 bdnz 1b
482 sync /* wait for dcbst's to get to ram */
483 mtctr r4
484 2: icbi 0,r6
485 addi r6,r6,L1_CACHE_BYTES
486 bdnz 2b
487 sync /* additional sync needed on g4 */
488 isync
489 blr
490 /*
491 * Write any modified data cache blocks out to memory.
492 * Does not invalidate the corresponding cache lines (especially for
493 * any corresponding instruction cache).
494 *
495 * clean_dcache_range(unsigned long start, unsigned long stop)
496 */
497 _GLOBAL(clean_dcache_range)
498 li r5,L1_CACHE_BYTES-1
499 andc r3,r3,r5
500 subf r4,r3,r4
501 add r4,r4,r5
502 srwi. r4,r4,L1_CACHE_SHIFT
503 beqlr
504 mtctr r4
506 1: dcbst 0,r3
507 addi r3,r3,L1_CACHE_BYTES
508 bdnz 1b
509 sync /* wait for dcbst's to get to ram */
510 blr
512 /*
513 * Write any modified data cache blocks out to memory and invalidate them.
514 * Does not invalidate the corresponding instruction cache blocks.
515 *
516 * flush_dcache_range(unsigned long start, unsigned long stop)
517 */
518 _GLOBAL(flush_dcache_range)
519 li r5,L1_CACHE_BYTES-1
520 andc r3,r3,r5
521 subf r4,r3,r4
522 add r4,r4,r5
523 srwi. r4,r4,L1_CACHE_SHIFT
524 beqlr
525 mtctr r4
527 1: dcbf 0,r3
528 addi r3,r3,L1_CACHE_BYTES
529 bdnz 1b
530 sync /* wait for dcbst's to get to ram */
531 blr
533 /*
534 * Like above, but invalidate the D-cache. This is used by the 8xx
535 * to invalidate the cache so the PPC core doesn't get stale data
536 * from the CPM (no cache snooping here :-).
537 *
538 * invalidate_dcache_range(unsigned long start, unsigned long stop)
539 */
540 _GLOBAL(invalidate_dcache_range)
541 li r5,L1_CACHE_BYTES-1
542 andc r3,r3,r5
543 subf r4,r3,r4
544 add r4,r4,r5
545 srwi. r4,r4,L1_CACHE_SHIFT
546 beqlr
547 mtctr r4
549 1: dcbi 0,r3
550 addi r3,r3,L1_CACHE_BYTES
551 bdnz 1b
552 sync /* wait for dcbi's to get to ram */
553 blr
555 /*
556 * Flush a particular page from the data cache to RAM.
557 * Note: this is necessary because the instruction cache does *not*
558 * snoop from the data cache.
559 * This is a no-op on the 601 which has a unified cache.
560 *
561 * void __flush_dcache_icache(void *page)
562 */
563 _GLOBAL(__flush_dcache_icache)
564 BEGIN_FTR_SECTION
565 blr
566 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
567 rlwinm r3,r3,0,0,19 /* Get page base address */
568 li r4,4096/L1_CACHE_BYTES /* Number of lines in a page */
569 mtctr r4
570 mr r6,r3
571 0: dcbst 0,r3 /* Write line to ram */
572 addi r3,r3,L1_CACHE_BYTES
573 bdnz 0b
574 sync
575 #ifndef CONFIG_44x
576 /* We don't flush the icache on 44x. Those have a virtual icache
577 * and we don't have access to the virtual address here (it's
578 * not the page vaddr but where it's mapped in user space). The
579 * flushing of the icache on these is handled elsewhere, when
580 * a change in the address space occurs, before returning to
581 * user space
582 */
583 mtctr r4
584 1: icbi 0,r6
585 addi r6,r6,L1_CACHE_BYTES
586 bdnz 1b
587 sync
588 isync
589 #endif /* CONFIG_44x */
590 blr
592 /*
593 * Flush a particular page from the data cache to RAM, identified
594 * by its physical address. We turn off the MMU so we can just use
595 * the physical address (this may be a highmem page without a kernel
596 * mapping).
597 *
598 * void __flush_dcache_icache_phys(unsigned long physaddr)
599 */
600 _GLOBAL(__flush_dcache_icache_phys)
601 BEGIN_FTR_SECTION
602 blr /* for 601, do nothing */
603 END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
604 mfmsr r10
605 rlwinm r0,r10,0,28,26 /* clear DR */
606 mtmsr r0
607 isync
608 rlwinm r3,r3,0,0,19 /* Get page base address */
609 li r4,4096/L1_CACHE_BYTES /* Number of lines in a page */
610 mtctr r4
611 mr r6,r3
612 0: dcbst 0,r3 /* Write line to ram */
613 addi r3,r3,L1_CACHE_BYTES
614 bdnz 0b
615 sync
616 mtctr r4
617 1: icbi 0,r6
618 addi r6,r6,L1_CACHE_BYTES
619 bdnz 1b
620 sync
621 mtmsr r10 /* restore DR */
622 isync
623 blr
625 /*
626 * Clear pages using the dcbz instruction, which doesn't cause any
627 * memory traffic (except to write out any cache lines which get
628 * displaced). This only works on cacheable memory.
629 *
630 * void clear_pages(void *page, int order) ;
631 */
632 _GLOBAL(clear_pages)
633 li r0,4096/L1_CACHE_BYTES
634 slw r0,r0,r4
635 mtctr r0
636 #ifdef CONFIG_8xx
637 li r4, 0
638 1: stw r4, 0(r3)
639 stw r4, 4(r3)
640 stw r4, 8(r3)
641 stw r4, 12(r3)
642 #else
643 1: dcbz 0,r3
644 #endif
645 addi r3,r3,L1_CACHE_BYTES
646 bdnz 1b
647 blr
649 /*
650 * Copy a whole page. We use the dcbz instruction on the destination
651 * to reduce memory traffic (it eliminates the unnecessary reads of
652 * the destination into cache). This requires that the destination
653 * is cacheable.
654 */
655 #define COPY_16_BYTES \
656 lwz r6,4(r4); \
657 lwz r7,8(r4); \
658 lwz r8,12(r4); \
659 lwzu r9,16(r4); \
660 stw r6,4(r3); \
661 stw r7,8(r3); \
662 stw r8,12(r3); \
663 stwu r9,16(r3)
665 _GLOBAL(copy_page)
666 addi r3,r3,-4
667 addi r4,r4,-4
669 #ifdef CONFIG_8xx
670 /* don't use prefetch on 8xx */
671 li r0,4096/L1_CACHE_BYTES
672 mtctr r0
673 1: COPY_16_BYTES
674 bdnz 1b
675 blr
677 #else /* not 8xx, we can prefetch */
678 li r5,4
680 #if MAX_COPY_PREFETCH > 1
681 li r0,MAX_COPY_PREFETCH
682 li r11,4
683 mtctr r0
684 11: dcbt r11,r4
685 addi r11,r11,L1_CACHE_BYTES
686 bdnz 11b
687 #else /* MAX_COPY_PREFETCH == 1 */
688 dcbt r5,r4
689 li r11,L1_CACHE_BYTES+4
690 #endif /* MAX_COPY_PREFETCH */
691 li r0,4096/L1_CACHE_BYTES - MAX_COPY_PREFETCH
692 crclr 4*cr0+eq
693 2:
694 mtctr r0
695 1:
696 dcbt r11,r4
697 dcbz r5,r3
698 COPY_16_BYTES
699 #if L1_CACHE_BYTES >= 32
700 COPY_16_BYTES
701 #if L1_CACHE_BYTES >= 64
702 COPY_16_BYTES
703 COPY_16_BYTES
704 #if L1_CACHE_BYTES >= 128
705 COPY_16_BYTES
706 COPY_16_BYTES
707 COPY_16_BYTES
708 COPY_16_BYTES
709 #endif
710 #endif
711 #endif
712 bdnz 1b
713 beqlr
714 crnot 4*cr0+eq,4*cr0+eq
715 li r0,MAX_COPY_PREFETCH
716 li r11,4
717 b 2b
718 #endif /* CONFIG_8xx */
720 /*
721 * void atomic_clear_mask(atomic_t mask, atomic_t *addr)
722 * void atomic_set_mask(atomic_t mask, atomic_t *addr);
723 */
724 _GLOBAL(atomic_clear_mask)
725 10: lwarx r5,0,r4
726 andc r5,r5,r3
727 PPC405_ERR77(0,r4)
728 stwcx. r5,0,r4
729 bne- 10b
730 blr
731 _GLOBAL(atomic_set_mask)
732 10: lwarx r5,0,r4
733 or r5,r5,r3
734 PPC405_ERR77(0,r4)
735 stwcx. r5,0,r4
736 bne- 10b
737 blr
739 /*
740 * Extended precision shifts.
741 *
742 * Updated to be valid for shift counts from 0 to 63 inclusive.
743 * -- Gabriel
744 *
745 * R3/R4 has 64 bit value
746 * R5 has shift count
747 * result in R3/R4
748 *
749 * ashrdi3: arithmetic right shift (sign propagation)
750 * lshrdi3: logical right shift
751 * ashldi3: left shift
752 */
753 _GLOBAL(__ashrdi3)
754 subfic r6,r5,32
755 srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
756 addi r7,r5,32 # could be xori, or addi with -32
757 slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
758 rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0
759 sraw r7,r3,r7 # t2 = MSW >> (count-32)
760 or r4,r4,r6 # LSW |= t1
761 slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2
762 sraw r3,r3,r5 # MSW = MSW >> count
763 or r4,r4,r7 # LSW |= t2
764 blr
766 _GLOBAL(__ashldi3)
767 subfic r6,r5,32
768 slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count
769 addi r7,r5,32 # could be xori, or addi with -32
770 srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count)
771 slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32)
772 or r3,r3,r6 # MSW |= t1
773 slw r4,r4,r5 # LSW = LSW << count
774 or r3,r3,r7 # MSW |= t2
775 blr
777 _GLOBAL(__lshrdi3)
778 subfic r6,r5,32
779 srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count
780 addi r7,r5,32 # could be xori, or addi with -32
781 slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count)
782 srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32)
783 or r4,r4,r6 # LSW |= t1
784 srw r3,r3,r5 # MSW = MSW >> count
785 or r4,r4,r7 # LSW |= t2
786 blr
788 _GLOBAL(abs)
789 srawi r4,r3,31
790 xor r3,r3,r4
791 sub r3,r3,r4
792 blr
794 /*
795 * Create a kernel thread
796 * kernel_thread(fn, arg, flags)
797 */
798 _GLOBAL(kernel_thread)
799 stwu r1,-16(r1)
800 stw r30,8(r1)
801 stw r31,12(r1)
802 mr r30,r3 /* function */
803 mr r31,r4 /* argument */
804 ori r3,r5,CLONE_VM /* flags */
805 oris r3,r3,CLONE_UNTRACED>>16
806 li r4,0 /* new sp (unused) */
807 li r0,__NR_clone
808 sc
809 cmpwi 0,r3,0 /* parent or child? */
810 bne 1f /* return if parent */
811 li r0,0 /* make top-level stack frame */
812 stwu r0,-16(r1)
813 mtlr r30 /* fn addr in lr */
814 mr r3,r31 /* load arg and call fn */
815 PPC440EP_ERR42
816 blrl
817 li r0,__NR_exit /* exit if function returns */
818 li r3,0
819 sc
820 1: lwz r30,8(r1)
821 lwz r31,12(r1)
822 addi r1,r1,16
823 blr
825 /*
826 * This routine is just here to keep GCC happy - sigh...
827 */
828 _GLOBAL(__main)
829 blr
831 #ifdef CONFIG_KEXEC
832 /*
833 * Must be relocatable PIC code callable as a C function.
834 */
835 .globl relocate_new_kernel
836 relocate_new_kernel:
837 /* r3 = page_list */
838 /* r4 = reboot_code_buffer */
839 /* r5 = start_address */
841 li r0, 0
843 /*
844 * Set Machine Status Register to a known status,
845 * switch the MMU off and jump to 1: in a single step.
846 */
848 mr r8, r0
849 ori r8, r8, MSR_RI|MSR_ME
850 mtspr SPRN_SRR1, r8
851 addi r8, r4, 1f - relocate_new_kernel
852 mtspr SPRN_SRR0, r8
853 sync
854 rfi
856 1:
857 /* from this point address translation is turned off */
858 /* and interrupts are disabled */
860 /* set a new stack at the bottom of our page... */
861 /* (not really needed now) */
862 addi r1, r4, KEXEC_CONTROL_CODE_SIZE - 8 /* for LR Save+Back Chain */
863 stw r0, 0(r1)
865 /* Do the copies */
866 li r6, 0 /* checksum */
867 mr r0, r3
868 b 1f
870 0: /* top, read another word for the indirection page */
871 lwzu r0, 4(r3)
873 1:
874 /* is it a destination page? (r8) */
875 rlwinm. r7, r0, 0, 31, 31 /* IND_DESTINATION (1<<0) */
876 beq 2f
878 rlwinm r8, r0, 0, 0, 19 /* clear kexec flags, page align */
879 b 0b
881 2: /* is it an indirection page? (r3) */
882 rlwinm. r7, r0, 0, 30, 30 /* IND_INDIRECTION (1<<1) */
883 beq 2f
885 rlwinm r3, r0, 0, 0, 19 /* clear kexec flags, page align */
886 subi r3, r3, 4
887 b 0b
889 2: /* are we done? */
890 rlwinm. r7, r0, 0, 29, 29 /* IND_DONE (1<<2) */
891 beq 2f
892 b 3f
894 2: /* is it a source page? (r9) */
895 rlwinm. r7, r0, 0, 28, 28 /* IND_SOURCE (1<<3) */
896 beq 0b
898 rlwinm r9, r0, 0, 0, 19 /* clear kexec flags, page align */
900 li r7, PAGE_SIZE / 4
901 mtctr r7
902 subi r9, r9, 4
903 subi r8, r8, 4
904 9:
905 lwzu r0, 4(r9) /* do the copy */
906 xor r6, r6, r0
907 stwu r0, 4(r8)
908 dcbst 0, r8
909 sync
910 icbi 0, r8
911 bdnz 9b
913 addi r9, r9, 4
914 addi r8, r8, 4
915 b 0b
917 3:
919 /* To be certain of avoiding problems with self-modifying code
920 * execute a serializing instruction here.
921 */
922 isync
923 sync
925 /* jump to the entry point, usually the setup routine */
926 mtlr r5
927 blrl
929 1: b 1b
931 relocate_new_kernel_end:
933 .globl relocate_new_kernel_size
934 relocate_new_kernel_size:
935 .long relocate_new_kernel_end - relocate_new_kernel
936 #endif