| blob | 725526547994d76ce6386d23d8398946357c6291 |
1 /*
2 * Kernel execution entry point code.
3 *
4 * Copyright (c) 1995-1996 Gary Thomas <gdt@linuxppc.org>
5 * Initial PowerPC version.
6 * Copyright (c) 1996 Cort Dougan <cort@cs.nmt.edu>
7 * Rewritten for PReP
8 * Copyright (c) 1996 Paul Mackerras <paulus@cs.anu.edu.au>
9 * Low-level exception handers, MMU support, and rewrite.
10 * Copyright (c) 1997 Dan Malek <dmalek@jlc.net>
11 * PowerPC 8xx modifications.
12 * Copyright (c) 1998-1999 TiVo, Inc.
13 * PowerPC 403GCX modifications.
14 * Copyright (c) 1999 Grant Erickson <grant@lcse.umn.edu>
15 * PowerPC 403GCX/405GP modifications.
16 * Copyright 2000 MontaVista Software Inc.
17 * PPC405 modifications
18 * PowerPC 403GCX/405GP modifications.
19 * Author: MontaVista Software, Inc.
20 * frank_rowand@mvista.com or source@mvista.com
21 * debbie_chu@mvista.com
22 * Copyright 2002-2004 MontaVista Software, Inc.
23 * PowerPC 44x support, Matt Porter <mporter@kernel.crashing.org>
24 * Copyright 2004 Freescale Semiconductor, Inc
25 * PowerPC e500 modifications, Kumar Gala <galak@kernel.crashing.org>
26 *
27 * This program is free software; you can redistribute it and/or modify it
28 * under the terms of the GNU General Public License as published by the
29 * Free Software Foundation; either version 2 of the License, or (at your
30 * option) any later version.
31 */
33 #include <linux/init.h>
34 #include <linux/threads.h>
35 #include <asm/processor.h>
36 #include <asm/page.h>
37 #include <asm/mmu.h>
38 #include <asm/pgtable.h>
39 #include <asm/cputable.h>
40 #include <asm/thread_info.h>
41 #include <asm/ppc_asm.h>
42 #include <asm/asm-offsets.h>
43 #include <asm/cache.h>
44 #include "head_booke.h"
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 _ENTRY(_stext);
59 _ENTRY(_start);
60 /*
61 * Reserve a word at a fixed location to store the address
62 * of abatron_pteptrs
63 */
64 nop
65 /*
66 * Save parameters we are passed
67 */
68 mr r31,r3
69 mr r30,r4
70 mr r29,r5
71 mr r28,r6
72 mr r27,r7
73 li r25,0 /* phys kernel start (low) */
74 li r24,0 /* CPU number */
75 li r23,0 /* phys kernel start (high) */
77 /* We try to not make any assumptions about how the boot loader
78 * setup or used the TLBs. We invalidate all mappings from the
79 * boot loader and load a single entry in TLB1[0] to map the
80 * first 64M of kernel memory. Any boot info passed from the
81 * bootloader needs to live in this first 64M.
82 *
83 * Requirement on bootloader:
84 * - The page we're executing in needs to reside in TLB1 and
85 * have IPROT=1. If not an invalidate broadcast could
86 * evict the entry we're currently executing in.
87 *
88 * r3 = Index of TLB1 were executing in
89 * r4 = Current MSR[IS]
90 * r5 = Index of TLB1 temp mapping
91 *
92 * Later in mapin_ram we will correctly map lowmem, and resize TLB1[0]
93 * if needed
94 */
96 _ENTRY(__early_start)
97 /* 1. Find the index of the entry we're executing in */
98 bl invstr /* Find our address */
99 invstr: mflr r6 /* Make it accessible */
100 mfmsr r7
101 rlwinm r4,r7,27,31,31 /* extract MSR[IS] */
102 mfspr r7, SPRN_PID0
103 slwi r7,r7,16
104 or r7,r7,r4
105 mtspr SPRN_MAS6,r7
106 tlbsx 0,r6 /* search MSR[IS], SPID=PID0 */
107 mfspr r7,SPRN_MAS1
108 andis. r7,r7,MAS1_VALID@h
109 bne match_TLB
111 mfspr r7,SPRN_MMUCFG
112 rlwinm r7,r7,21,28,31 /* extract MMUCFG[NPIDS] */
113 cmpwi r7,3
114 bne match_TLB /* skip if NPIDS != 3 */
116 mfspr r7,SPRN_PID1
117 slwi r7,r7,16
118 or r7,r7,r4
119 mtspr SPRN_MAS6,r7
120 tlbsx 0,r6 /* search MSR[IS], SPID=PID1 */
121 mfspr r7,SPRN_MAS1
122 andis. r7,r7,MAS1_VALID@h
123 bne match_TLB
124 mfspr r7, SPRN_PID2
125 slwi r7,r7,16
126 or r7,r7,r4
127 mtspr SPRN_MAS6,r7
128 tlbsx 0,r6 /* Fall through, we had to match */
130 match_TLB:
131 mfspr r7,SPRN_MAS0
132 rlwinm r3,r7,16,20,31 /* Extract MAS0(Entry) */
134 mfspr r7,SPRN_MAS1 /* Insure IPROT set */
135 oris r7,r7,MAS1_IPROT@h
136 mtspr SPRN_MAS1,r7
137 tlbwe
139 /* 2. Invalidate all entries except the entry we're executing in */
140 mfspr r9,SPRN_TLB1CFG
141 andi. r9,r9,0xfff
142 li r6,0 /* Set Entry counter to 0 */
143 1: lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
144 rlwimi r7,r6,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r6) */
145 mtspr SPRN_MAS0,r7
146 tlbre
147 mfspr r7,SPRN_MAS1
148 rlwinm r7,r7,0,2,31 /* Clear MAS1 Valid and IPROT */
149 cmpw r3,r6
150 beq skpinv /* Dont update the current execution TLB */
151 mtspr SPRN_MAS1,r7
152 tlbwe
153 isync
154 skpinv: addi r6,r6,1 /* Increment */
155 cmpw r6,r9 /* Are we done? */
156 bne 1b /* If not, repeat */
158 /* Invalidate TLB0 */
159 li r6,0x04
160 tlbivax 0,r6
161 TLBSYNC
162 /* Invalidate TLB1 */
163 li r6,0x0c
164 tlbivax 0,r6
165 TLBSYNC
167 /* 3. Setup a temp mapping and jump to it */
168 andi. r5, r3, 0x1 /* Find an entry not used and is non-zero */
169 addi r5, r5, 0x1
170 lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
171 rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
172 mtspr SPRN_MAS0,r7
173 tlbre
175 /* grab and fixup the RPN */
176 mfspr r6,SPRN_MAS1 /* extract MAS1[SIZE] */
177 rlwinm r6,r6,25,27,31
178 li r8,-1
179 addi r6,r6,10
180 slw r6,r8,r6 /* convert to mask */
182 bl 1f /* Find our address */
183 1: mflr r7
185 mfspr r8,SPRN_MAS3
186 #ifdef CONFIG_PHYS_64BIT
187 mfspr r23,SPRN_MAS7
188 #endif
189 and r8,r6,r8
190 subfic r9,r6,-4096
191 and r9,r9,r7
193 or r25,r8,r9
194 ori r8,r25,(MAS3_SX|MAS3_SW|MAS3_SR)
196 /* Just modify the entry ID and EPN for the temp mapping */
197 lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
198 rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */
199 mtspr SPRN_MAS0,r7
200 xori r6,r4,1 /* Setup TMP mapping in the other Address space */
201 slwi r6,r6,12
202 oris r6,r6,(MAS1_VALID|MAS1_IPROT)@h
203 ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_4K))@l
204 mtspr SPRN_MAS1,r6
205 mfspr r6,SPRN_MAS2
206 li r7,0 /* temp EPN = 0 */
207 rlwimi r7,r6,0,20,31
208 mtspr SPRN_MAS2,r7
209 mtspr SPRN_MAS3,r8
210 tlbwe
212 xori r6,r4,1
213 slwi r6,r6,5 /* setup new context with other address space */
214 bl 1f /* Find our address */
215 1: mflr r9
216 rlwimi r7,r9,0,20,31
217 addi r7,r7,(2f - 1b)
218 mtspr SPRN_SRR0,r7
219 mtspr SPRN_SRR1,r6
220 rfi
221 2:
222 /* 4. Clear out PIDs & Search info */
223 li r6,0
224 mtspr SPRN_MAS6,r6
225 mtspr SPRN_PID0,r6
227 mfspr r7,SPRN_MMUCFG
228 rlwinm r7,r7,21,28,31 /* extract MMUCFG[NPIDS] */
229 cmpwi r7,3
230 bne 2f /* skip if NPIDS != 3 */
232 mtspr SPRN_PID1,r6
233 mtspr SPRN_PID2,r6
235 /* 5. Invalidate mapping we started in */
236 2:
237 lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
238 rlwimi r7,r3,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r3) */
239 mtspr SPRN_MAS0,r7
240 tlbre
241 mfspr r6,SPRN_MAS1
242 rlwinm r6,r6,0,2,0 /* clear IPROT */
243 mtspr SPRN_MAS1,r6
244 tlbwe
245 /* Invalidate TLB1 */
246 li r9,0x0c
247 tlbivax 0,r9
248 TLBSYNC
250 /* The mapping only needs to be cache-coherent on SMP */
251 #ifdef CONFIG_SMP
252 #define M_IF_SMP MAS2_M
253 #else
254 #define M_IF_SMP 0
255 #endif
257 /* 6. Setup KERNELBASE mapping in TLB1[0] */
258 lis r6,0x1000 /* Set MAS0(TLBSEL) = TLB1(1), ESEL = 0 */
259 mtspr SPRN_MAS0,r6
260 lis r6,(MAS1_VALID|MAS1_IPROT)@h
261 ori r6,r6,(MAS1_TSIZE(BOOK3E_PAGESZ_64M))@l
262 mtspr SPRN_MAS1,r6
263 lis r6,MAS2_VAL(PAGE_OFFSET, BOOK3E_PAGESZ_64M, M_IF_SMP)@h
264 ori r6,r6,MAS2_VAL(PAGE_OFFSET, BOOK3E_PAGESZ_64M, M_IF_SMP)@l
265 mtspr SPRN_MAS2,r6
266 mtspr SPRN_MAS3,r8
267 tlbwe
269 /* 7. Jump to KERNELBASE mapping */
270 lis r6,(KERNELBASE & ~0xfff)@h
271 ori r6,r6,(KERNELBASE & ~0xfff)@l
272 lis r7,MSR_KERNEL@h
273 ori r7,r7,MSR_KERNEL@l
274 bl 1f /* Find our address */
275 1: mflr r9
276 rlwimi r6,r9,0,20,31
277 addi r6,r6,(2f - 1b)
278 mtspr SPRN_SRR0,r6
279 mtspr SPRN_SRR1,r7
280 rfi /* start execution out of TLB1[0] entry */
282 /* 8. Clear out the temp mapping */
283 2: lis r7,0x1000 /* Set MAS0(TLBSEL) = 1 */
284 rlwimi r7,r5,16,4,15 /* Setup MAS0 = TLBSEL | ESEL(r5) */
285 mtspr SPRN_MAS0,r7
286 tlbre
287 mfspr r8,SPRN_MAS1
288 rlwinm r8,r8,0,2,0 /* clear IPROT */
289 mtspr SPRN_MAS1,r8
290 tlbwe
291 /* Invalidate TLB1 */
292 li r9,0x0c
293 tlbivax 0,r9
294 TLBSYNC
296 /* Establish the interrupt vector offsets */
297 SET_IVOR(0, CriticalInput);
298 SET_IVOR(1, MachineCheck);
299 SET_IVOR(2, DataStorage);
300 SET_IVOR(3, InstructionStorage);
301 SET_IVOR(4, ExternalInput);
302 SET_IVOR(5, Alignment);
303 SET_IVOR(6, Program);
304 SET_IVOR(7, FloatingPointUnavailable);
305 SET_IVOR(8, SystemCall);
306 SET_IVOR(9, AuxillaryProcessorUnavailable);
307 SET_IVOR(10, Decrementer);
308 SET_IVOR(11, FixedIntervalTimer);
309 SET_IVOR(12, WatchdogTimer);
310 SET_IVOR(13, DataTLBError);
311 SET_IVOR(14, InstructionTLBError);
312 SET_IVOR(15, DebugCrit);
314 /* Establish the interrupt vector base */
315 lis r4,interrupt_base@h /* IVPR only uses the high 16-bits */
316 mtspr SPRN_IVPR,r4
318 /* Setup the defaults for TLB entries */
319 li r2,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
320 #ifdef CONFIG_E200
321 oris r2,r2,MAS4_TLBSELD(1)@h
322 #endif
323 mtspr SPRN_MAS4, r2
325 #if 0
326 /* Enable DOZE */
327 mfspr r2,SPRN_HID0
328 oris r2,r2,HID0_DOZE@h
329 mtspr SPRN_HID0, r2
330 #endif
332 #if !defined(CONFIG_BDI_SWITCH)
333 /*
334 * The Abatron BDI JTAG debugger does not tolerate others
335 * mucking with the debug registers.
336 */
337 lis r2,DBCR0_IDM@h
338 mtspr SPRN_DBCR0,r2
339 isync
340 /* clear any residual debug events */
341 li r2,-1
342 mtspr SPRN_DBSR,r2
343 #endif
345 #ifdef CONFIG_SMP
346 /* Check to see if we're the second processor, and jump
347 * to the secondary_start code if so
348 */
349 mfspr r24,SPRN_PIR
350 cmpwi r24,0
351 bne __secondary_start
352 #endif
354 /*
355 * This is where the main kernel code starts.
356 */
358 /* ptr to current */
359 lis r2,init_task@h
360 ori r2,r2,init_task@l
362 /* ptr to current thread */
363 addi r4,r2,THREAD /* init task's THREAD */
364 mtspr SPRN_SPRG_THREAD,r4
366 /* stack */
367 lis r1,init_thread_union@h
368 ori r1,r1,init_thread_union@l
369 li r0,0
370 stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
372 bl early_init
374 #ifdef CONFIG_RELOCATABLE
375 lis r3,kernstart_addr@ha
376 la r3,kernstart_addr@l(r3)
377 #ifdef CONFIG_PHYS_64BIT
378 stw r23,0(r3)
379 stw r25,4(r3)
380 #else
381 stw r25,0(r3)
382 #endif
383 #endif
385 /*
386 * Decide what sort of machine this is and initialize the MMU.
387 */
388 mr r3,r31
389 mr r4,r30
390 mr r5,r29
391 mr r6,r28
392 mr r7,r27
393 bl machine_init
394 bl MMU_init
396 /* Setup PTE pointers for the Abatron bdiGDB */
397 lis r6, swapper_pg_dir@h
398 ori r6, r6, swapper_pg_dir@l
399 lis r5, abatron_pteptrs@h
400 ori r5, r5, abatron_pteptrs@l
401 lis r4, KERNELBASE@h
402 ori r4, r4, KERNELBASE@l
403 stw r5, 0(r4) /* Save abatron_pteptrs at a fixed location */
404 stw r6, 0(r5)
406 /* Let's move on */
407 lis r4,start_kernel@h
408 ori r4,r4,start_kernel@l
409 lis r3,MSR_KERNEL@h
410 ori r3,r3,MSR_KERNEL@l
411 mtspr SPRN_SRR0,r4
412 mtspr SPRN_SRR1,r3
413 rfi /* change context and jump to start_kernel */
415 /* Macros to hide the PTE size differences
416 *
417 * FIND_PTE -- walks the page tables given EA & pgdir pointer
418 * r10 -- EA of fault
419 * r11 -- PGDIR pointer
420 * r12 -- free
421 * label 2: is the bailout case
422 *
423 * if we find the pte (fall through):
424 * r11 is low pte word
425 * r12 is pointer to the pte
426 */
427 #ifdef CONFIG_PTE_64BIT
428 #define FIND_PTE \
429 rlwinm r12, r10, 13, 19, 29; /* Compute pgdir/pmd offset */ \
430 lwzx r11, r12, r11; /* Get pgd/pmd entry */ \
431 rlwinm. r12, r11, 0, 0, 20; /* Extract pt base address */ \
432 beq 2f; /* Bail if no table */ \
433 rlwimi r12, r10, 23, 20, 28; /* Compute pte address */ \
434 lwz r11, 4(r12); /* Get pte entry */
435 #else
436 #define FIND_PTE \
437 rlwimi r11, r10, 12, 20, 29; /* Create L1 (pgdir/pmd) address */ \
438 lwz r11, 0(r11); /* Get L1 entry */ \
439 rlwinm. r12, r11, 0, 0, 19; /* Extract L2 (pte) base address */ \
440 beq 2f; /* Bail if no table */ \
441 rlwimi r12, r10, 22, 20, 29; /* Compute PTE address */ \
442 lwz r11, 0(r12); /* Get Linux PTE */
443 #endif
445 /*
446 * Interrupt vector entry code
447 *
448 * The Book E MMUs are always on so we don't need to handle
449 * interrupts in real mode as with previous PPC processors. In
450 * this case we handle interrupts in the kernel virtual address
451 * space.
452 *
453 * Interrupt vectors are dynamically placed relative to the
454 * interrupt prefix as determined by the address of interrupt_base.
455 * The interrupt vectors offsets are programmed using the labels
456 * for each interrupt vector entry.
457 *
458 * Interrupt vectors must be aligned on a 16 byte boundary.
459 * We align on a 32 byte cache line boundary for good measure.
460 */
462 interrupt_base:
463 /* Critical Input Interrupt */
464 CRITICAL_EXCEPTION(0x0100, CriticalInput, unknown_exception)
466 /* Machine Check Interrupt */
467 #ifdef CONFIG_E200
468 /* no RFMCI, MCSRRs on E200 */
469 CRITICAL_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
470 #else
471 MCHECK_EXCEPTION(0x0200, MachineCheck, machine_check_exception)
472 #endif
474 /* Data Storage Interrupt */
475 START_EXCEPTION(DataStorage)
476 NORMAL_EXCEPTION_PROLOG
477 mfspr r5,SPRN_ESR /* Grab the ESR, save it, pass arg3 */
478 stw r5,_ESR(r11)
479 mfspr r4,SPRN_DEAR /* Grab the DEAR, save it, pass arg2 */
480 andis. r10,r5,(ESR_ILK|ESR_DLK)@h
481 bne 1f
482 EXC_XFER_EE_LITE(0x0300, handle_page_fault)
483 1:
484 addi r3,r1,STACK_FRAME_OVERHEAD
485 EXC_XFER_EE_LITE(0x0300, CacheLockingException)
487 /* Instruction Storage Interrupt */
488 INSTRUCTION_STORAGE_EXCEPTION
490 /* External Input Interrupt */
491 EXCEPTION(0x0500, ExternalInput, do_IRQ, EXC_XFER_LITE)
493 /* Alignment Interrupt */
494 ALIGNMENT_EXCEPTION
496 /* Program Interrupt */
497 PROGRAM_EXCEPTION
499 /* Floating Point Unavailable Interrupt */
500 #ifdef CONFIG_PPC_FPU
501 FP_UNAVAILABLE_EXCEPTION
502 #else
503 #ifdef CONFIG_E200
504 /* E200 treats 'normal' floating point instructions as FP Unavail exception */
505 EXCEPTION(0x0800, FloatingPointUnavailable, program_check_exception, EXC_XFER_EE)
506 #else
507 EXCEPTION(0x0800, FloatingPointUnavailable, unknown_exception, EXC_XFER_EE)
508 #endif
509 #endif
511 /* System Call Interrupt */
512 START_EXCEPTION(SystemCall)
513 NORMAL_EXCEPTION_PROLOG
514 EXC_XFER_EE_LITE(0x0c00, DoSyscall)
516 /* Auxillary Processor Unavailable Interrupt */
517 EXCEPTION(0x2900, AuxillaryProcessorUnavailable, unknown_exception, EXC_XFER_EE)
519 /* Decrementer Interrupt */
520 DECREMENTER_EXCEPTION
522 /* Fixed Internal Timer Interrupt */
523 /* TODO: Add FIT support */
524 EXCEPTION(0x3100, FixedIntervalTimer, unknown_exception, EXC_XFER_EE)
526 /* Watchdog Timer Interrupt */
527 #ifdef CONFIG_BOOKE_WDT
528 CRITICAL_EXCEPTION(0x3200, WatchdogTimer, WatchdogException)
529 #else
530 CRITICAL_EXCEPTION(0x3200, WatchdogTimer, unknown_exception)
531 #endif
533 /* Data TLB Error Interrupt */
534 START_EXCEPTION(DataTLBError)
535 mtspr SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
536 mtspr SPRN_SPRG_WSCRATCH1, r11
537 mtspr SPRN_SPRG_WSCRATCH2, r12
538 mtspr SPRN_SPRG_WSCRATCH3, r13
539 mfcr r11
540 mtspr SPRN_SPRG_WSCRATCH4, r11
541 mfspr r10, SPRN_DEAR /* Get faulting address */
543 /* If we are faulting a kernel address, we have to use the
544 * kernel page tables.
545 */
546 lis r11, PAGE_OFFSET@h
547 cmplw 5, r10, r11
548 blt 5, 3f
549 lis r11, swapper_pg_dir@h
550 ori r11, r11, swapper_pg_dir@l
552 mfspr r12,SPRN_MAS1 /* Set TID to 0 */
553 rlwinm r12,r12,0,16,1
554 mtspr SPRN_MAS1,r12
556 b 4f
558 /* Get the PGD for the current thread */
559 3:
560 mfspr r11,SPRN_SPRG_THREAD
561 lwz r11,PGDIR(r11)
563 4:
564 /* Mask of required permission bits. Note that while we
565 * do copy ESR:ST to _PAGE_RW position as trying to write
566 * to an RO page is pretty common, we don't do it with
567 * _PAGE_DIRTY. We could do it, but it's a fairly rare
568 * event so I'd rather take the overhead when it happens
569 * rather than adding an instruction here. We should measure
570 * whether the whole thing is worth it in the first place
571 * as we could avoid loading SPRN_ESR completely in the first
572 * place...
573 *
574 * TODO: Is it worth doing that mfspr & rlwimi in the first
575 * place or can we save a couple of instructions here ?
576 */
577 mfspr r12,SPRN_ESR
578 #ifdef CONFIG_PTE_64BIT
579 li r13,_PAGE_PRESENT
580 oris r13,r13,_PAGE_ACCESSED@h
581 #else
582 li r13,_PAGE_PRESENT|_PAGE_ACCESSED
583 #endif
584 rlwimi r13,r12,11,29,29
586 FIND_PTE
587 andc. r13,r13,r11 /* Check permission */
589 #ifdef CONFIG_PTE_64BIT
590 #ifdef CONFIG_SMP
591 subf r10,r11,r12 /* create false data dep */
592 lwzx r13,r11,r10 /* Get upper pte bits */
593 #else
594 lwz r13,0(r12) /* Get upper pte bits */
595 #endif
596 #endif
598 bne 2f /* Bail if permission/valid mismach */
600 /* Jump to common tlb load */
601 b finish_tlb_load
602 2:
603 /* The bailout. Restore registers to pre-exception conditions
604 * and call the heavyweights to help us out.
605 */
606 mfspr r11, SPRN_SPRG_RSCRATCH4
607 mtcr r11
608 mfspr r13, SPRN_SPRG_RSCRATCH3
609 mfspr r12, SPRN_SPRG_RSCRATCH2
610 mfspr r11, SPRN_SPRG_RSCRATCH1
611 mfspr r10, SPRN_SPRG_RSCRATCH0
612 b DataStorage
614 /* Instruction TLB Error Interrupt */
615 /*
616 * Nearly the same as above, except we get our
617 * information from different registers and bailout
618 * to a different point.
619 */
620 START_EXCEPTION(InstructionTLBError)
621 mtspr SPRN_SPRG_WSCRATCH0, r10 /* Save some working registers */
622 mtspr SPRN_SPRG_WSCRATCH1, r11
623 mtspr SPRN_SPRG_WSCRATCH2, r12
624 mtspr SPRN_SPRG_WSCRATCH3, r13
625 mfcr r11
626 mtspr SPRN_SPRG_WSCRATCH4, r11
627 mfspr r10, SPRN_SRR0 /* Get faulting address */
629 /* If we are faulting a kernel address, we have to use the
630 * kernel page tables.
631 */
632 lis r11, PAGE_OFFSET@h
633 cmplw 5, r10, r11
634 blt 5, 3f
635 lis r11, swapper_pg_dir@h
636 ori r11, r11, swapper_pg_dir@l
638 mfspr r12,SPRN_MAS1 /* Set TID to 0 */
639 rlwinm r12,r12,0,16,1
640 mtspr SPRN_MAS1,r12
642 b 4f
644 /* Get the PGD for the current thread */
645 3:
646 mfspr r11,SPRN_SPRG_THREAD
647 lwz r11,PGDIR(r11)
649 4:
650 /* Make up the required permissions */
651 #ifdef CONFIG_PTE_64BIT
652 li r13,_PAGE_PRESENT | _PAGE_EXEC
653 oris r13,r13,_PAGE_ACCESSED@h
654 #else
655 li r13,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
656 #endif
658 FIND_PTE
659 andc. r13,r13,r11 /* Check permission */
661 #ifdef CONFIG_PTE_64BIT
662 #ifdef CONFIG_SMP
663 subf r10,r11,r12 /* create false data dep */
664 lwzx r13,r11,r10 /* Get upper pte bits */
665 #else
666 lwz r13,0(r12) /* Get upper pte bits */
667 #endif
668 #endif
670 bne 2f /* Bail if permission mismach */
672 /* Jump to common TLB load point */
673 b finish_tlb_load
675 2:
676 /* The bailout. Restore registers to pre-exception conditions
677 * and call the heavyweights to help us out.
678 */
679 mfspr r11, SPRN_SPRG_RSCRATCH4
680 mtcr r11
681 mfspr r13, SPRN_SPRG_RSCRATCH3
682 mfspr r12, SPRN_SPRG_RSCRATCH2
683 mfspr r11, SPRN_SPRG_RSCRATCH1
684 mfspr r10, SPRN_SPRG_RSCRATCH0
685 b InstructionStorage
687 #ifdef CONFIG_SPE
688 /* SPE Unavailable */
689 START_EXCEPTION(SPEUnavailable)
690 NORMAL_EXCEPTION_PROLOG
691 bne load_up_spe
692 addi r3,r1,STACK_FRAME_OVERHEAD
693 EXC_XFER_EE_LITE(0x2010, KernelSPE)
694 #else
695 EXCEPTION(0x2020, SPEUnavailable, unknown_exception, EXC_XFER_EE)
696 #endif /* CONFIG_SPE */
698 /* SPE Floating Point Data */
699 #ifdef CONFIG_SPE
700 EXCEPTION(0x2030, SPEFloatingPointData, SPEFloatingPointException, EXC_XFER_EE);
702 /* SPE Floating Point Round */
703 EXCEPTION(0x2050, SPEFloatingPointRound, SPEFloatingPointRoundException, EXC_XFER_EE)
704 #else
705 EXCEPTION(0x2040, SPEFloatingPointData, unknown_exception, EXC_XFER_EE)
706 EXCEPTION(0x2050, SPEFloatingPointRound, unknown_exception, EXC_XFER_EE)
707 #endif /* CONFIG_SPE */
709 /* Performance Monitor */
710 EXCEPTION(0x2060, PerformanceMonitor, performance_monitor_exception, EXC_XFER_STD)
712 EXCEPTION(0x2070, Doorbell, doorbell_exception, EXC_XFER_STD)
714 CRITICAL_EXCEPTION(0x2080, CriticalDoorbell, unknown_exception)
716 /* Debug Interrupt */
717 DEBUG_DEBUG_EXCEPTION
718 DEBUG_CRIT_EXCEPTION
720 /*
721 * Local functions
722 */
724 /*
725 * Both the instruction and data TLB miss get to this
726 * point to load the TLB.
727 * r10 - available to use
728 * r11 - TLB (info from Linux PTE)
729 * r12 - available to use
730 * r13 - upper bits of PTE (if PTE_64BIT) or available to use
731 * CR5 - results of addr >= PAGE_OFFSET
732 * MAS0, MAS1 - loaded with proper value when we get here
733 * MAS2, MAS3 - will need additional info from Linux PTE
734 * Upon exit, we reload everything and RFI.
735 */
736 finish_tlb_load:
737 /*
738 * We set execute, because we don't have the granularity to
739 * properly set this at the page level (Linux problem).
740 * Many of these bits are software only. Bits we don't set
741 * here we (properly should) assume have the appropriate value.
742 */
744 mfspr r12, SPRN_MAS2
745 #ifdef CONFIG_PTE_64BIT
746 rlwimi r12, r11, 32-19, 27, 31 /* extract WIMGE from pte */
747 #else
748 rlwimi r12, r11, 26, 27, 31 /* extract WIMGE from pte */
749 #endif
750 mtspr SPRN_MAS2, r12
752 #ifdef CONFIG_PTE_64BIT
753 rlwinm r12, r11, 32-2, 26, 31 /* Move in perm bits */
754 andi. r10, r11, _PAGE_DIRTY
755 bne 1f
756 li r10, MAS3_SW | MAS3_UW
757 andc r12, r12, r10
758 1: rlwimi r12, r13, 20, 0, 11 /* grab RPN[32:43] */
759 rlwimi r12, r11, 20, 12, 19 /* grab RPN[44:51] */
760 mtspr SPRN_MAS3, r12
761 BEGIN_MMU_FTR_SECTION
762 srwi r10, r13, 12 /* grab RPN[12:31] */
763 mtspr SPRN_MAS7, r10
764 END_MMU_FTR_SECTION_IFSET(MMU_FTR_BIG_PHYS)
765 #else
766 li r10, (_PAGE_EXEC | _PAGE_PRESENT)
767 rlwimi r10, r11, 31, 29, 29 /* extract _PAGE_DIRTY into SW */
768 and r12, r11, r10
769 andi. r10, r11, _PAGE_USER /* Test for _PAGE_USER */
770 slwi r10, r12, 1
771 or r10, r10, r12
772 iseleq r12, r12, r10
773 rlwimi r11, r12, 0, 20, 31 /* Extract RPN from PTE and merge with perms */
774 mtspr SPRN_MAS3, r11
775 #endif
776 #ifdef CONFIG_E200
777 /* Round robin TLB1 entries assignment */
778 mfspr r12, SPRN_MAS0
780 /* Extract TLB1CFG(NENTRY) */
781 mfspr r11, SPRN_TLB1CFG
782 andi. r11, r11, 0xfff
784 /* Extract MAS0(NV) */
785 andi. r13, r12, 0xfff
786 addi r13, r13, 1
787 cmpw 0, r13, r11
788 addi r12, r12, 1
790 /* check if we need to wrap */
791 blt 7f
793 /* wrap back to first free tlbcam entry */
794 lis r13, tlbcam_index@ha
795 lwz r13, tlbcam_index@l(r13)
796 rlwimi r12, r13, 0, 20, 31
797 7:
798 mtspr SPRN_MAS0,r12
799 #endif /* CONFIG_E200 */
801 tlbwe
803 /* Done...restore registers and get out of here. */
804 mfspr r11, SPRN_SPRG_RSCRATCH4
805 mtcr r11
806 mfspr r13, SPRN_SPRG_RSCRATCH3
807 mfspr r12, SPRN_SPRG_RSCRATCH2
808 mfspr r11, SPRN_SPRG_RSCRATCH1
809 mfspr r10, SPRN_SPRG_RSCRATCH0
810 rfi /* Force context change */
812 #ifdef CONFIG_SPE
813 /* Note that the SPE support is closely modeled after the AltiVec
814 * support. Changes to one are likely to be applicable to the
815 * other! */
816 load_up_spe:
817 /*
818 * Disable SPE for the task which had SPE previously,
819 * and save its SPE registers in its thread_struct.
820 * Enables SPE for use in the kernel on return.
821 * On SMP we know the SPE units are free, since we give it up every
822 * switch. -- Kumar
823 */
824 mfmsr r5
825 oris r5,r5,MSR_SPE@h
826 mtmsr r5 /* enable use of SPE now */
827 isync
828 /*
829 * For SMP, we don't do lazy SPE switching because it just gets too
830 * horrendously complex, especially when a task switches from one CPU
831 * to another. Instead we call giveup_spe in switch_to.
832 */
833 #ifndef CONFIG_SMP
834 lis r3,last_task_used_spe@ha
835 lwz r4,last_task_used_spe@l(r3)
836 cmpi 0,r4,0
837 beq 1f
838 addi r4,r4,THREAD /* want THREAD of last_task_used_spe */
839 SAVE_32EVRS(0,r10,r4)
840 evxor evr10, evr10, evr10 /* clear out evr10 */
841 evmwumiaa evr10, evr10, evr10 /* evr10 <- ACC = 0 * 0 + ACC */
842 li r5,THREAD_ACC
843 evstddx evr10, r4, r5 /* save off accumulator */
844 lwz r5,PT_REGS(r4)
845 lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
846 lis r10,MSR_SPE@h
847 andc r4,r4,r10 /* disable SPE for previous task */
848 stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
849 1:
850 #endif /* !CONFIG_SMP */
851 /* enable use of SPE after return */
852 oris r9,r9,MSR_SPE@h
853 mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
854 li r4,1
855 li r10,THREAD_ACC
856 stw r4,THREAD_USED_SPE(r5)
857 evlddx evr4,r10,r5
858 evmra evr4,evr4
859 REST_32EVRS(0,r10,r5)
860 #ifndef CONFIG_SMP
861 subi r4,r5,THREAD
862 stw r4,last_task_used_spe@l(r3)
863 #endif /* !CONFIG_SMP */
864 /* restore registers and return */
865 2: REST_4GPRS(3, r11)
866 lwz r10,_CCR(r11)
867 REST_GPR(1, r11)
868 mtcr r10
869 lwz r10,_LINK(r11)
870 mtlr r10
871 REST_GPR(10, r11)
872 mtspr SPRN_SRR1,r9
873 mtspr SPRN_SRR0,r12
874 REST_GPR(9, r11)
875 REST_GPR(12, r11)
876 lwz r11,GPR11(r11)
877 rfi
879 /*
880 * SPE unavailable trap from kernel - print a message, but let
881 * the task use SPE in the kernel until it returns to user mode.
882 */
883 KernelSPE:
884 lwz r3,_MSR(r1)
885 oris r3,r3,MSR_SPE@h
886 stw r3,_MSR(r1) /* enable use of SPE after return */
887 #ifdef CONFIG_PRINTK
888 lis r3,87f@h
889 ori r3,r3,87f@l
890 mr r4,r2 /* current */
891 lwz r5,_NIP(r1)
892 bl printk
893 #endif
894 b ret_from_except
895 #ifdef CONFIG_PRINTK
896 87: .string "SPE used in kernel (task=%p, pc=%x) \n"
897 #endif
898 .align 4,0
900 #endif /* CONFIG_SPE */
902 /*
903 * Global functions
904 */
906 /* Adjust or setup IVORs for e200 */
907 _GLOBAL(__setup_e200_ivors)
908 li r3,DebugDebug@l
909 mtspr SPRN_IVOR15,r3
910 li r3,SPEUnavailable@l
911 mtspr SPRN_IVOR32,r3
912 li r3,SPEFloatingPointData@l
913 mtspr SPRN_IVOR33,r3
914 li r3,SPEFloatingPointRound@l
915 mtspr SPRN_IVOR34,r3
916 sync
917 blr
919 /* Adjust or setup IVORs for e500v1/v2 */
920 _GLOBAL(__setup_e500_ivors)
921 li r3,DebugCrit@l
922 mtspr SPRN_IVOR15,r3
923 li r3,SPEUnavailable@l
924 mtspr SPRN_IVOR32,r3
925 li r3,SPEFloatingPointData@l
926 mtspr SPRN_IVOR33,r3
927 li r3,SPEFloatingPointRound@l
928 mtspr SPRN_IVOR34,r3
929 li r3,PerformanceMonitor@l
930 mtspr SPRN_IVOR35,r3
931 sync
932 blr
934 /* Adjust or setup IVORs for e500mc */
935 _GLOBAL(__setup_e500mc_ivors)
936 li r3,DebugDebug@l
937 mtspr SPRN_IVOR15,r3
938 li r3,PerformanceMonitor@l
939 mtspr SPRN_IVOR35,r3
940 li r3,Doorbell@l
941 mtspr SPRN_IVOR36,r3
942 li r3,CriticalDoorbell@l
943 mtspr SPRN_IVOR37,r3
944 sync
945 blr
947 /*
948 * extern void giveup_altivec(struct task_struct *prev)
949 *
950 * The e500 core does not have an AltiVec unit.
951 */
952 _GLOBAL(giveup_altivec)
953 blr
955 #ifdef CONFIG_SPE
956 /*
957 * extern void giveup_spe(struct task_struct *prev)
958 *
959 */
960 _GLOBAL(giveup_spe)
961 mfmsr r5
962 oris r5,r5,MSR_SPE@h
963 mtmsr r5 /* enable use of SPE now */
964 isync
965 cmpi 0,r3,0
966 beqlr- /* if no previous owner, done */
967 addi r3,r3,THREAD /* want THREAD of task */
968 lwz r5,PT_REGS(r3)
969 cmpi 0,r5,0
970 SAVE_32EVRS(0, r4, r3)
971 evxor evr6, evr6, evr6 /* clear out evr6 */
972 evmwumiaa evr6, evr6, evr6 /* evr6 <- ACC = 0 * 0 + ACC */
973 li r4,THREAD_ACC
974 evstddx evr6, r4, r3 /* save off accumulator */
975 mfspr r6,SPRN_SPEFSCR
976 stw r6,THREAD_SPEFSCR(r3) /* save spefscr register value */
977 beq 1f
978 lwz r4,_MSR-STACK_FRAME_OVERHEAD(r5)
979 lis r3,MSR_SPE@h
980 andc r4,r4,r3 /* disable SPE for previous task */
981 stw r4,_MSR-STACK_FRAME_OVERHEAD(r5)
982 1:
983 #ifndef CONFIG_SMP
984 li r5,0
985 lis r4,last_task_used_spe@ha
986 stw r5,last_task_used_spe@l(r4)
987 #endif /* !CONFIG_SMP */
988 blr
989 #endif /* CONFIG_SPE */
991 /*
992 * extern void giveup_fpu(struct task_struct *prev)
993 *
994 * Not all FSL Book-E cores have an FPU
995 */
996 #ifndef CONFIG_PPC_FPU
997 _GLOBAL(giveup_fpu)
998 blr
999 #endif
1001 /*
1002 * extern void abort(void)
1003 *
1004 * At present, this routine just applies a system reset.
1005 */
1006 _GLOBAL(abort)
1007 li r13,0
1008 mtspr SPRN_DBCR0,r13 /* disable all debug events */
1009 isync
1010 mfmsr r13
1011 ori r13,r13,MSR_DE@l /* Enable Debug Events */
1012 mtmsr r13
1013 isync
1014 mfspr r13,SPRN_DBCR0
1015 lis r13,(DBCR0_IDM|DBCR0_RST_CHIP)@h
1016 mtspr SPRN_DBCR0,r13
1017 isync
1019 _GLOBAL(set_context)
1021 #ifdef CONFIG_BDI_SWITCH
1022 /* Context switch the PTE pointer for the Abatron BDI2000.
1023 * The PGDIR is the second parameter.
1024 */
1025 lis r5, abatron_pteptrs@h
1026 ori r5, r5, abatron_pteptrs@l
1027 stw r4, 0x4(r5)
1028 #endif
1029 mtspr SPRN_PID,r3
1030 isync /* Force context change */
1031 blr
1033 _GLOBAL(flush_dcache_L1)
1034 mfspr r3,SPRN_L1CFG0
1036 rlwinm r5,r3,9,3 /* Extract cache block size */
1037 twlgti r5,1 /* Only 32 and 64 byte cache blocks
1038 * are currently defined.
1039 */
1040 li r4,32
1041 subfic r6,r5,2 /* r6 = log2(1KiB / cache block size) -
1042 * log2(number of ways)
1043 */
1044 slw r5,r4,r5 /* r5 = cache block size */
1046 rlwinm r7,r3,0,0xff /* Extract number of KiB in the cache */
1047 mulli r7,r7,13 /* An 8-way cache will require 13
1048 * loads per set.
1049 */
1050 slw r7,r7,r6
1052 /* save off HID0 and set DCFA */
1053 mfspr r8,SPRN_HID0
1054 ori r9,r8,HID0_DCFA@l
1055 mtspr SPRN_HID0,r9
1056 isync
1058 lis r4,KERNELBASE@h
1059 mtctr r7
1061 1: lwz r3,0(r4) /* Load... */
1062 add r4,r4,r5
1063 bdnz 1b
1065 msync
1066 lis r4,KERNELBASE@h
1067 mtctr r7
1069 1: dcbf 0,r4 /* ...and flush. */
1070 add r4,r4,r5
1071 bdnz 1b
1073 /* restore HID0 */
1074 mtspr SPRN_HID0,r8
1075 isync
1077 blr
1079 #ifdef CONFIG_SMP
1080 /* When we get here, r24 needs to hold the CPU # */
1081 .globl __secondary_start
1082 __secondary_start:
1083 lis r3,__secondary_hold_acknowledge@h
1084 ori r3,r3,__secondary_hold_acknowledge@l
1085 stw r24,0(r3)
1087 li r3,0
1088 mr r4,r24 /* Why? */
1089 bl call_setup_cpu
1091 lis r3,tlbcam_index@ha
1092 lwz r3,tlbcam_index@l(r3)
1093 mtctr r3
1094 li r26,0 /* r26 safe? */
1096 /* Load each CAM entry */
1097 1: mr r3,r26
1098 bl loadcam_entry
1099 addi r26,r26,1
1100 bdnz 1b
1102 /* get current_thread_info and current */
1103 lis r1,secondary_ti@ha
1104 lwz r1,secondary_ti@l(r1)
1105 lwz r2,TI_TASK(r1)
1107 /* stack */
1108 addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
1109 li r0,0
1110 stw r0,0(r1)
1112 /* ptr to current thread */
1113 addi r4,r2,THREAD /* address of our thread_struct */
1114 mtspr SPRN_SPRG_THREAD,r4
1116 /* Setup the defaults for TLB entries */
1117 li r4,(MAS4_TSIZED(BOOK3E_PAGESZ_4K))@l
1118 mtspr SPRN_MAS4,r4
1120 /* Jump to start_secondary */
1121 lis r4,MSR_KERNEL@h
1122 ori r4,r4,MSR_KERNEL@l
1123 lis r3,start_secondary@h
1124 ori r3,r3,start_secondary@l
1125 mtspr SPRN_SRR0,r3
1126 mtspr SPRN_SRR1,r4
1127 sync
1128 rfi
1129 sync
1131 .globl __secondary_hold_acknowledge
1132 __secondary_hold_acknowledge:
1133 .long -1
1134 #endif
1136 /*
1137 * We put a few things here that have to be page-aligned. This stuff
1138 * goes at the beginning of the data segment, which is page-aligned.
1139 */
1140 .data
1141 .align 12
1142 .globl sdata
1143 sdata:
1144 .globl empty_zero_page
1145 empty_zero_page:
1146 .space 4096
1147 .globl swapper_pg_dir
1148 swapper_pg_dir:
1149 .space PGD_TABLE_SIZE
1151 /*
1152 * Room for two PTE pointers, usually the kernel and current user pointers
1153 * to their respective root page table.
1154 */
1155 abatron_pteptrs:
1156 .space 8