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1 /*
2 * PowerPC version
3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
4 *
5 * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
6 * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
7 * Adapted for Power Macintosh by Paul Mackerras.
8 * Low-level exception handlers and MMU support
9 * rewritten by Paul Mackerras.
10 * Copyright (C) 1996 Paul Mackerras.
11 * MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
12 *
13 * This file contains the low-level support and setup for the
14 * PowerPC platform, including trap and interrupt dispatch.
15 * (The PPC 8xx embedded CPUs use head_8xx.S instead.)
16 *
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
21 *
22 */
23
24 #include <linux/init.h>
25 #include <asm/reg.h>
26 #include <asm/page.h>
27 #include <asm/mmu.h>
28 #include <asm/pgtable.h>
29 #include <asm/cputable.h>
30 #include <asm/cache.h>
31 #include <asm/thread_info.h>
32 #include <asm/ppc_asm.h>
33 #include <asm/asm-offsets.h>
34 #include <asm/ptrace.h>
35 #include <asm/bug.h>
36 #include <asm/kvm_book3s_asm.h>
37 #include <asm/export.h>
38
39 /* 601 only have IBAT; cr0.eq is set on 601 when using this macro */
40 #define LOAD_BAT(n, reg, RA, RB) \
41 /* see the comment for clear_bats() -- Cort */ \
42 li RA,0; \
43 mtspr SPRN_IBAT##n##U,RA; \
44 mtspr SPRN_DBAT##n##U,RA; \
45 lwz RA,(n*16)+0(reg); \
46 lwz RB,(n*16)+4(reg); \
47 mtspr SPRN_IBAT##n##U,RA; \
48 mtspr SPRN_IBAT##n##L,RB; \
49 beq 1f; \
50 lwz RA,(n*16)+8(reg); \
51 lwz RB,(n*16)+12(reg); \
52 mtspr SPRN_DBAT##n##U,RA; \
53 mtspr SPRN_DBAT##n##L,RB; \
54 1:
55
56 __HEAD
57 .stabs "arch/powerpc/kernel/",N_SO,0,0,0f
58 .stabs "head_32.S",N_SO,0,0,0f
59 0:
60 _ENTRY(_stext);
61
62 /*
63 * _start is defined this way because the XCOFF loader in the OpenFirmware
64 * on the powermac expects the entry point to be a procedure descriptor.
65 */
66 _ENTRY(_start);
67 /*
68 * These are here for legacy reasons, the kernel used to
69 * need to look like a coff function entry for the pmac
70 * but we're always started by some kind of bootloader now.
71 * -- Cort
72 */
73 nop /* used by __secondary_hold on prep (mtx) and chrp smp */
74 nop /* used by __secondary_hold on prep (mtx) and chrp smp */
75 nop
76
77 /* PMAC
78 * Enter here with the kernel text, data and bss loaded starting at
79 * 0, running with virtual == physical mapping.
80 * r5 points to the prom entry point (the client interface handler
81 * address). Address translation is turned on, with the prom
82 * managing the hash table. Interrupts are disabled. The stack
83 * pointer (r1) points to just below the end of the half-meg region
84 * from 0x380000 - 0x400000, which is mapped in already.
85 *
86 * If we are booted from MacOS via BootX, we enter with the kernel
87 * image loaded somewhere, and the following values in registers:
88 * r3: 'BooX' (0x426f6f58)
89 * r4: virtual address of boot_infos_t
90 * r5: 0
91 *
92 * PREP
93 * This is jumped to on prep systems right after the kernel is relocated
94 * to its proper place in memory by the boot loader. The expected layout
95 * of the regs is:
96 * r3: ptr to residual data
97 * r4: initrd_start or if no initrd then 0
98 * r5: initrd_end - unused if r4 is 0
99 * r6: Start of command line string
100 * r7: End of command line string
101 *
102 * This just gets a minimal mmu environment setup so we can call
103 * start_here() to do the real work.
104 * -- Cort
105 */
106
107 .globl __start
108 __start:
109 /*
110 * We have to do any OF calls before we map ourselves to KERNELBASE,
111 * because OF may have I/O devices mapped into that area
112 * (particularly on CHRP).
113 */
114 cmpwi 0,r5,0
115 beq 1f
116
117 #ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE
118 /* find out where we are now */
119 bcl 20,31,$+4
120 0: mflr r8 /* r8 = runtime addr here */
121 addis r8,r8,(_stext - 0b)@ha
122 addi r8,r8,(_stext - 0b)@l /* current runtime base addr */
123 bl prom_init
124 #endif /* CONFIG_PPC_OF_BOOT_TRAMPOLINE */
125
126 /* We never return. We also hit that trap if trying to boot
127 * from OF while CONFIG_PPC_OF_BOOT_TRAMPOLINE isn't selected */
128 trap
129
130 /*
131 * Check for BootX signature when supporting PowerMac and branch to
132 * appropriate trampoline if it's present
133 */
134 #ifdef CONFIG_PPC_PMAC
135 1: lis r31,0x426f
136 ori r31,r31,0x6f58
137 cmpw 0,r3,r31
138 bne 1f
139 bl bootx_init
140 trap
141 #endif /* CONFIG_PPC_PMAC */
142
143 1: mr r31,r3 /* save device tree ptr */
144 li r24,0 /* cpu # */
145
146 /*
147 * early_init() does the early machine identification and does
148 * the necessary low-level setup and clears the BSS
149 * -- Cort <cort@fsmlabs.com>
150 */
151 bl early_init
152
153 /* Switch MMU off, clear BATs and flush TLB. At this point, r3 contains
154 * the physical address we are running at, returned by early_init()
155 */
156 bl mmu_off
157 __after_mmu_off:
158 bl clear_bats
159 bl flush_tlbs
160
161 bl initial_bats
162 #if defined(CONFIG_BOOTX_TEXT)
163 bl setup_disp_bat
164 #endif
165 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
166 bl setup_cpm_bat
167 #endif
168 #ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
169 bl setup_usbgecko_bat
170 #endif
171
172 /*
173 * Call setup_cpu for CPU 0 and initialize 6xx Idle
174 */
175 bl reloc_offset
176 li r24,0 /* cpu# */
177 bl call_setup_cpu /* Call setup_cpu for this CPU */
178 #ifdef CONFIG_6xx
179 bl reloc_offset
180 bl init_idle_6xx
181 #endif /* CONFIG_6xx */
182
183
184 /*
185 * We need to run with _start at physical address 0.
186 * On CHRP, we are loaded at 0x10000 since OF on CHRP uses
187 * the exception vectors at 0 (and therefore this copy
188 * overwrites OF's exception vectors with our own).
189 * The MMU is off at this point.
190 */
191 bl reloc_offset
192 mr r26,r3
193 addis r4,r3,KERNELBASE@h /* current address of _start */
194 lis r5,PHYSICAL_START@h
195 cmplw 0,r4,r5 /* already running at PHYSICAL_START? */
196 bne relocate_kernel
197 /*
198 * we now have the 1st 16M of ram mapped with the bats.
199 * prep needs the mmu to be turned on here, but pmac already has it on.
200 * this shouldn't bother the pmac since it just gets turned on again
201 * as we jump to our code at KERNELBASE. -- Cort
202 * Actually no, pmac doesn't have it on any more. BootX enters with MMU
203 * off, and in other cases, we now turn it off before changing BATs above.
204 */
205 turn_on_mmu:
206 mfmsr r0
207 ori r0,r0,MSR_DR|MSR_IR
208 mtspr SPRN_SRR1,r0
209 lis r0,start_here@h
210 ori r0,r0,start_here@l
211 mtspr SPRN_SRR0,r0
212 SYNC
213 RFI /* enables MMU */
214
215 /*
216 * We need __secondary_hold as a place to hold the other cpus on
217 * an SMP machine, even when we are running a UP kernel.
218 */
219 . = 0xc0 /* for prep bootloader */
220 li r3,1 /* MTX only has 1 cpu */
221 .globl __secondary_hold
222 __secondary_hold:
223 /* tell the master we're here */
224 stw r3,__secondary_hold_acknowledge@l(0)
225 #ifdef CONFIG_SMP
226 100: lwz r4,0(0)
227 /* wait until we're told to start */
228 cmpw 0,r4,r3
229 bne 100b
230 /* our cpu # was at addr 0 - go */
231 mr r24,r3 /* cpu # */
232 b __secondary_start
233 #else
234 b .
235 #endif /* CONFIG_SMP */
236
237 .globl __secondary_hold_spinloop
238 __secondary_hold_spinloop:
239 .long 0
240 .globl __secondary_hold_acknowledge
241 __secondary_hold_acknowledge:
242 .long -1
243
244 /*
245 * Exception entry code. This code runs with address translation
246 * turned off, i.e. using physical addresses.
247 * We assume sprg3 has the physical address of the current
248 * task's thread_struct.
249 */
250 #define EXCEPTION_PROLOG \
251 mtspr SPRN_SPRG_SCRATCH0,r10; \
252 mtspr SPRN_SPRG_SCRATCH1,r11; \
253 mfcr r10; \
254 EXCEPTION_PROLOG_1; \
255 EXCEPTION_PROLOG_2
256
257 #define EXCEPTION_PROLOG_1 \
258 mfspr r11,SPRN_SRR1; /* check whether user or kernel */ \
259 andi. r11,r11,MSR_PR; \
260 tophys(r11,r1); /* use tophys(r1) if kernel */ \
261 beq 1f; \
262 mfspr r11,SPRN_SPRG_THREAD; \
263 lwz r11,THREAD_INFO-THREAD(r11); \
264 addi r11,r11,THREAD_SIZE; \
265 tophys(r11,r11); \
266 1: subi r11,r11,INT_FRAME_SIZE /* alloc exc. frame */
267
268
269 #define EXCEPTION_PROLOG_2 \
270 stw r10,_CCR(r11); /* save registers */ \
271 stw r12,GPR12(r11); \
272 stw r9,GPR9(r11); \
273 mfspr r10,SPRN_SPRG_SCRATCH0; \
274 stw r10,GPR10(r11); \
275 mfspr r12,SPRN_SPRG_SCRATCH1; \
276 stw r12,GPR11(r11); \
277 mflr r10; \
278 stw r10,_LINK(r11); \
279 mfspr r12,SPRN_SRR0; \
280 mfspr r9,SPRN_SRR1; \
281 stw r1,GPR1(r11); \
282 stw r1,0(r11); \
283 tovirt(r1,r11); /* set new kernel sp */ \
284 li r10,MSR_KERNEL & ~(MSR_IR|MSR_DR); /* can take exceptions */ \
285 MTMSRD(r10); /* (except for mach check in rtas) */ \
286 stw r0,GPR0(r11); \
287 lis r10,STACK_FRAME_REGS_MARKER@ha; /* exception frame marker */ \
288 addi r10,r10,STACK_FRAME_REGS_MARKER@l; \
289 stw r10,8(r11); \
290 SAVE_4GPRS(3, r11); \
291 SAVE_2GPRS(7, r11)
292
293 /*
294 * Note: code which follows this uses cr0.eq (set if from kernel),
295 * r11, r12 (SRR0), and r9 (SRR1).
296 *
297 * Note2: once we have set r1 we are in a position to take exceptions
298 * again, and we could thus set MSR:RI at that point.
299 */
300
301 /*
302 * Exception vectors.
303 */
304 #define EXCEPTION(n, label, hdlr, xfer) \
305 . = n; \
306 DO_KVM n; \
307 label: \
308 EXCEPTION_PROLOG; \
309 addi r3,r1,STACK_FRAME_OVERHEAD; \
310 xfer(n, hdlr)
311
312 #define EXC_XFER_TEMPLATE(n, hdlr, trap, copyee, tfer, ret) \
313 li r10,trap; \
314 stw r10,_TRAP(r11); \
315 li r10,MSR_KERNEL; \
316 copyee(r10, r9); \
317 bl tfer; \
318 i##n: \
319 .long hdlr; \
320 .long ret
321
322 #define COPY_EE(d, s) rlwimi d,s,0,16,16
323 #define NOCOPY(d, s)
324
325 #define EXC_XFER_STD(n, hdlr) \
326 EXC_XFER_TEMPLATE(n, hdlr, n, NOCOPY, transfer_to_handler_full, \
327 ret_from_except_full)
328
329 #define EXC_XFER_LITE(n, hdlr) \
330 EXC_XFER_TEMPLATE(n, hdlr, n+1, NOCOPY, transfer_to_handler, \
331 ret_from_except)
332
333 #define EXC_XFER_EE(n, hdlr) \
334 EXC_XFER_TEMPLATE(n, hdlr, n, COPY_EE, transfer_to_handler_full, \
335 ret_from_except_full)
336
337 #define EXC_XFER_EE_LITE(n, hdlr) \
338 EXC_XFER_TEMPLATE(n, hdlr, n+1, COPY_EE, transfer_to_handler, \
339 ret_from_except)
340
341 /* System reset */
342 /* core99 pmac starts the seconary here by changing the vector, and
343 putting it back to what it was (unknown_exception) when done. */
344 EXCEPTION(0x100, Reset, unknown_exception, EXC_XFER_STD)
345
346 /* Machine check */
347 /*
348 * On CHRP, this is complicated by the fact that we could get a
349 * machine check inside RTAS, and we have no guarantee that certain
350 * critical registers will have the values we expect. The set of
351 * registers that might have bad values includes all the GPRs
352 * and all the BATs. We indicate that we are in RTAS by putting
353 * a non-zero value, the address of the exception frame to use,
354 * in SPRG2. The machine check handler checks SPRG2 and uses its
355 * value if it is non-zero. If we ever needed to free up SPRG2,
356 * we could use a field in the thread_info or thread_struct instead.
357 * (Other exception handlers assume that r1 is a valid kernel stack
358 * pointer when we take an exception from supervisor mode.)
359 * -- paulus.
360 */
361 . = 0x200
362 DO_KVM 0x200
363 mtspr SPRN_SPRG_SCRATCH0,r10
364 mtspr SPRN_SPRG_SCRATCH1,r11
365 mfcr r10
366 #ifdef CONFIG_PPC_CHRP
367 mfspr r11,SPRN_SPRG_RTAS
368 cmpwi 0,r11,0
369 bne 7f
370 #endif /* CONFIG_PPC_CHRP */
371 EXCEPTION_PROLOG_1
372 7: EXCEPTION_PROLOG_2
373 addi r3,r1,STACK_FRAME_OVERHEAD
374 #ifdef CONFIG_PPC_CHRP
375 mfspr r4,SPRN_SPRG_RTAS
376 cmpwi cr1,r4,0
377 bne cr1,1f
378 #endif
379 EXC_XFER_STD(0x200, machine_check_exception)
380 #ifdef CONFIG_PPC_CHRP
381 1: b machine_check_in_rtas
382 #endif
383
384 /* Data access exception. */
385 . = 0x300
386 DO_KVM 0x300
387 DataAccess:
388 EXCEPTION_PROLOG
389 mfspr r10,SPRN_DSISR
390 stw r10,_DSISR(r11)
391 andis. r0,r10,0xa470 /* weird error? */
392 bne 1f /* if not, try to put a PTE */
393 mfspr r4,SPRN_DAR /* into the hash table */
394 rlwinm r3,r10,32-15,21,21 /* DSISR_STORE -> _PAGE_RW */
395 bl hash_page
396 1: lwz r5,_DSISR(r11) /* get DSISR value */
397 mfspr r4,SPRN_DAR
398 EXC_XFER_LITE(0x300, handle_page_fault)
399
400
401 /* Instruction access exception. */
402 . = 0x400
403 DO_KVM 0x400
404 InstructionAccess:
405 EXCEPTION_PROLOG
406 andis. r0,r9,0x4000 /* no pte found? */
407 beq 1f /* if so, try to put a PTE */
408 li r3,0 /* into the hash table */
409 mr r4,r12 /* SRR0 is fault address */
410 bl hash_page
411 1: mr r4,r12
412 mr r5,r9
413 EXC_XFER_LITE(0x400, handle_page_fault)
414
415 /* External interrupt */
416 EXCEPTION(0x500, HardwareInterrupt, do_IRQ, EXC_XFER_LITE)
417
418 /* Alignment exception */
419 . = 0x600
420 DO_KVM 0x600
421 Alignment:
422 EXCEPTION_PROLOG
423 mfspr r4,SPRN_DAR
424 stw r4,_DAR(r11)
425 mfspr r5,SPRN_DSISR
426 stw r5,_DSISR(r11)
427 addi r3,r1,STACK_FRAME_OVERHEAD
428 EXC_XFER_EE(0x600, alignment_exception)
429
430 /* Program check exception */
431 EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
432
433 /* Floating-point unavailable */
434 . = 0x800
435 DO_KVM 0x800
436 FPUnavailable:
437 BEGIN_FTR_SECTION
438 /*
439 * Certain Freescale cores don't have a FPU and treat fp instructions
440 * as a FP Unavailable exception. Redirect to illegal/emulation handling.
441 */
442 b ProgramCheck
443 END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
444 EXCEPTION_PROLOG
445 beq 1f
446 bl load_up_fpu /* if from user, just load it up */
447 b fast_exception_return
448 1: addi r3,r1,STACK_FRAME_OVERHEAD
449 EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
450
451 /* Decrementer */
452 EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
453
454 EXCEPTION(0xa00, Trap_0a, unknown_exception, EXC_XFER_EE)
455 EXCEPTION(0xb00, Trap_0b, unknown_exception, EXC_XFER_EE)
456
457 /* System call */
458 . = 0xc00
459 DO_KVM 0xc00
460 SystemCall:
461 EXCEPTION_PROLOG
462 EXC_XFER_EE_LITE(0xc00, DoSyscall)
463
464 /* Single step - not used on 601 */
465 EXCEPTION(0xd00, SingleStep, single_step_exception, EXC_XFER_STD)
466 EXCEPTION(0xe00, Trap_0e, unknown_exception, EXC_XFER_EE)
467
468 /*
469 * The Altivec unavailable trap is at 0x0f20. Foo.
470 * We effectively remap it to 0x3000.
471 * We include an altivec unavailable exception vector even if
472 * not configured for Altivec, so that you can't panic a
473 * non-altivec kernel running on a machine with altivec just
474 * by executing an altivec instruction.
475 */
476 . = 0xf00
477 DO_KVM 0xf00
478 b PerformanceMonitor
479
480 . = 0xf20
481 DO_KVM 0xf20
482 b AltiVecUnavailable
483
484 /*
485 * Handle TLB miss for instruction on 603/603e.
486 * Note: we get an alternate set of r0 - r3 to use automatically.
487 */
488 . = 0x1000
489 InstructionTLBMiss:
490 /*
491 * r0: scratch
492 * r1: linux style pte ( later becomes ppc hardware pte )
493 * r2: ptr to linux-style pte
494 * r3: scratch
495 */
496 /* Get PTE (linux-style) and check access */
497 mfspr r3,SPRN_IMISS
498 lis r1,PAGE_OFFSET@h /* check if kernel address */
499 cmplw 0,r1,r3
500 mfspr r2,SPRN_SPRG_THREAD
501 li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
502 lwz r2,PGDIR(r2)
503 bge- 112f
504 mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
505 rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
506 lis r2,swapper_pg_dir@ha /* if kernel address, use */
507 addi r2,r2,swapper_pg_dir@l /* kernel page table */
508 112: tophys(r2,r2)
509 rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
510 lwz r2,0(r2) /* get pmd entry */
511 rlwinm. r2,r2,0,0,19 /* extract address of pte page */
512 beq- InstructionAddressInvalid /* return if no mapping */
513 rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
514 lwz r0,0(r2) /* get linux-style pte */
515 andc. r1,r1,r0 /* check access & ~permission */
516 bne- InstructionAddressInvalid /* return if access not permitted */
517 ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
518 /*
519 * NOTE! We are assuming this is not an SMP system, otherwise
520 * we would need to update the pte atomically with lwarx/stwcx.
521 */
522 stw r0,0(r2) /* update PTE (accessed bit) */
523 /* Convert linux-style PTE to low word of PPC-style PTE */
524 rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
525 rlwinm r2,r0,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
526 and r1,r1,r2 /* writable if _RW and _DIRTY */
527 rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
528 rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
529 ori r1,r1,0xe04 /* clear out reserved bits */
530 andc r1,r0,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
531 BEGIN_FTR_SECTION
532 rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
533 END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
534 mtspr SPRN_RPA,r1
535 tlbli r3
536 mfspr r3,SPRN_SRR1 /* Need to restore CR0 */
537 mtcrf 0x80,r3
538 rfi
539 InstructionAddressInvalid:
540 mfspr r3,SPRN_SRR1
541 rlwinm r1,r3,9,6,6 /* Get load/store bit */
542
543 addis r1,r1,0x2000
544 mtspr SPRN_DSISR,r1 /* (shouldn't be needed) */
545 andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */
546 or r2,r2,r1
547 mtspr SPRN_SRR1,r2
548 mfspr r1,SPRN_IMISS /* Get failing address */
549 rlwinm. r2,r2,0,31,31 /* Check for little endian access */
550 rlwimi r2,r2,1,30,30 /* change 1 -> 3 */
551 xor r1,r1,r2
552 mtspr SPRN_DAR,r1 /* Set fault address */
553 mfmsr r0 /* Restore "normal" registers */
554 xoris r0,r0,MSR_TGPR>>16
555 mtcrf 0x80,r3 /* Restore CR0 */
556 mtmsr r0
557 b InstructionAccess
558
559 /*
560 * Handle TLB miss for DATA Load operation on 603/603e
561 */
562 . = 0x1100
563 DataLoadTLBMiss:
564 /*
565 * r0: scratch
566 * r1: linux style pte ( later becomes ppc hardware pte )
567 * r2: ptr to linux-style pte
568 * r3: scratch
569 */
570 /* Get PTE (linux-style) and check access */
571 mfspr r3,SPRN_DMISS
572 lis r1,PAGE_OFFSET@h /* check if kernel address */
573 cmplw 0,r1,r3
574 mfspr r2,SPRN_SPRG_THREAD
575 li r1,_PAGE_USER|_PAGE_PRESENT /* low addresses tested as user */
576 lwz r2,PGDIR(r2)
577 bge- 112f
578 mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
579 rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
580 lis r2,swapper_pg_dir@ha /* if kernel address, use */
581 addi r2,r2,swapper_pg_dir@l /* kernel page table */
582 112: tophys(r2,r2)
583 rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
584 lwz r2,0(r2) /* get pmd entry */
585 rlwinm. r2,r2,0,0,19 /* extract address of pte page */
586 beq- DataAddressInvalid /* return if no mapping */
587 rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
588 lwz r0,0(r2) /* get linux-style pte */
589 andc. r1,r1,r0 /* check access & ~permission */
590 bne- DataAddressInvalid /* return if access not permitted */
591 ori r0,r0,_PAGE_ACCESSED /* set _PAGE_ACCESSED in pte */
592 /*
593 * NOTE! We are assuming this is not an SMP system, otherwise
594 * we would need to update the pte atomically with lwarx/stwcx.
595 */
596 stw r0,0(r2) /* update PTE (accessed bit) */
597 /* Convert linux-style PTE to low word of PPC-style PTE */
598 rlwinm r1,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */
599 rlwinm r2,r0,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */
600 and r1,r1,r2 /* writable if _RW and _DIRTY */
601 rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
602 rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */
603 ori r1,r1,0xe04 /* clear out reserved bits */
604 andc r1,r0,r1 /* PP = user? (rw&dirty? 2: 3): 0 */
605 BEGIN_FTR_SECTION
606 rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
607 END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
608 mtspr SPRN_RPA,r1
609 mfspr r2,SPRN_SRR1 /* Need to restore CR0 */
610 mtcrf 0x80,r2
611 BEGIN_MMU_FTR_SECTION
612 li r0,1
613 mfspr r1,SPRN_SPRG_603_LRU
614 rlwinm r2,r3,20,27,31 /* Get Address bits 15:19 */
615 slw r0,r0,r2
616 xor r1,r0,r1
617 srw r0,r1,r2
618 mtspr SPRN_SPRG_603_LRU,r1
619 mfspr r2,SPRN_SRR1
620 rlwimi r2,r0,31-14,14,14
621 mtspr SPRN_SRR1,r2
622 END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
623 tlbld r3
624 rfi
625 DataAddressInvalid:
626 mfspr r3,SPRN_SRR1
627 rlwinm r1,r3,9,6,6 /* Get load/store bit */
628 addis r1,r1,0x2000
629 mtspr SPRN_DSISR,r1
630 andi. r2,r3,0xFFFF /* Clear upper bits of SRR1 */
631 mtspr SPRN_SRR1,r2
632 mfspr r1,SPRN_DMISS /* Get failing address */
633 rlwinm. r2,r2,0,31,31 /* Check for little endian access */
634 beq 20f /* Jump if big endian */
635 xori r1,r1,3
636 20: mtspr SPRN_DAR,r1 /* Set fault address */
637 mfmsr r0 /* Restore "normal" registers */
638 xoris r0,r0,MSR_TGPR>>16
639 mtcrf 0x80,r3 /* Restore CR0 */
640 mtmsr r0
641 b DataAccess
642
643 /*
644 * Handle TLB miss for DATA Store on 603/603e
645 */
646 . = 0x1200
647 DataStoreTLBMiss:
648 /*
649 * r0: scratch
650 * r1: linux style pte ( later becomes ppc hardware pte )
651 * r2: ptr to linux-style pte
652 * r3: scratch
653 */
654 /* Get PTE (linux-style) and check access */
655 mfspr r3,SPRN_DMISS
656 lis r1,PAGE_OFFSET@h /* check if kernel address */
657 cmplw 0,r1,r3
658 mfspr r2,SPRN_SPRG_THREAD
659 li r1,_PAGE_RW|_PAGE_USER|_PAGE_PRESENT /* access flags */
660 lwz r2,PGDIR(r2)
661 bge- 112f
662 mfspr r2,SPRN_SRR1 /* and MSR_PR bit from SRR1 */
663 rlwimi r1,r2,32-12,29,29 /* shift MSR_PR to _PAGE_USER posn */
664 lis r2,swapper_pg_dir@ha /* if kernel address, use */
665 addi r2,r2,swapper_pg_dir@l /* kernel page table */
666 112: tophys(r2,r2)
667 rlwimi r2,r3,12,20,29 /* insert top 10 bits of address */
668 lwz r2,0(r2) /* get pmd entry */
669 rlwinm. r2,r2,0,0,19 /* extract address of pte page */
670 beq- DataAddressInvalid /* return if no mapping */
671 rlwimi r2,r3,22,20,29 /* insert next 10 bits of address */
672 lwz r0,0(r2) /* get linux-style pte */
673 andc. r1,r1,r0 /* check access & ~permission */
674 bne- DataAddressInvalid /* return if access not permitted */
675 ori r0,r0,_PAGE_ACCESSED|_PAGE_DIRTY
676 /*
677 * NOTE! We are assuming this is not an SMP system, otherwise
678 * we would need to update the pte atomically with lwarx/stwcx.
679 */
680 stw r0,0(r2) /* update PTE (accessed/dirty bits) */
681 /* Convert linux-style PTE to low word of PPC-style PTE */
682 rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */
683 li r1,0xe05 /* clear out reserved bits & PP lsb */
684 andc r1,r0,r1 /* PP = user? 2: 0 */
685 BEGIN_FTR_SECTION
686 rlwinm r1,r1,0,~_PAGE_COHERENT /* clear M (coherence not required) */
687 END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
688 mtspr SPRN_RPA,r1
689 mfspr r2,SPRN_SRR1 /* Need to restore CR0 */
690 mtcrf 0x80,r2
691 BEGIN_MMU_FTR_SECTION
692 li r0,1
693 mfspr r1,SPRN_SPRG_603_LRU
694 rlwinm r2,r3,20,27,31 /* Get Address bits 15:19 */
695 slw r0,r0,r2
696 xor r1,r0,r1
697 srw r0,r1,r2
698 mtspr SPRN_SPRG_603_LRU,r1
699 mfspr r2,SPRN_SRR1
700 rlwimi r2,r0,31-14,14,14
701 mtspr SPRN_SRR1,r2
702 END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
703 tlbld r3
704 rfi
705
706 #ifndef CONFIG_ALTIVEC
707 #define altivec_assist_exception unknown_exception
708 #endif
709
710 EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception, EXC_XFER_EE)
711 EXCEPTION(0x1400, SMI, SMIException, EXC_XFER_EE)
712 EXCEPTION(0x1500, Trap_15, unknown_exception, EXC_XFER_EE)
713 EXCEPTION(0x1600, Trap_16, altivec_assist_exception, EXC_XFER_EE)
714 EXCEPTION(0x1700, Trap_17, TAUException, EXC_XFER_STD)
715 EXCEPTION(0x1800, Trap_18, unknown_exception, EXC_XFER_EE)
716 EXCEPTION(0x1900, Trap_19, unknown_exception, EXC_XFER_EE)
717 EXCEPTION(0x1a00, Trap_1a, unknown_exception, EXC_XFER_EE)
718 EXCEPTION(0x1b00, Trap_1b, unknown_exception, EXC_XFER_EE)
719 EXCEPTION(0x1c00, Trap_1c, unknown_exception, EXC_XFER_EE)
720 EXCEPTION(0x1d00, Trap_1d, unknown_exception, EXC_XFER_EE)
721 EXCEPTION(0x1e00, Trap_1e, unknown_exception, EXC_XFER_EE)
722 EXCEPTION(0x1f00, Trap_1f, unknown_exception, EXC_XFER_EE)
723 EXCEPTION(0x2000, RunMode, RunModeException, EXC_XFER_EE)
724 EXCEPTION(0x2100, Trap_21, unknown_exception, EXC_XFER_EE)
725 EXCEPTION(0x2200, Trap_22, unknown_exception, EXC_XFER_EE)
726 EXCEPTION(0x2300, Trap_23, unknown_exception, EXC_XFER_EE)
727 EXCEPTION(0x2400, Trap_24, unknown_exception, EXC_XFER_EE)
728 EXCEPTION(0x2500, Trap_25, unknown_exception, EXC_XFER_EE)
729 EXCEPTION(0x2600, Trap_26, unknown_exception, EXC_XFER_EE)
730 EXCEPTION(0x2700, Trap_27, unknown_exception, EXC_XFER_EE)
731 EXCEPTION(0x2800, Trap_28, unknown_exception, EXC_XFER_EE)
732 EXCEPTION(0x2900, Trap_29, unknown_exception, EXC_XFER_EE)
733 EXCEPTION(0x2a00, Trap_2a, unknown_exception, EXC_XFER_EE)
734 EXCEPTION(0x2b00, Trap_2b, unknown_exception, EXC_XFER_EE)
735 EXCEPTION(0x2c00, Trap_2c, unknown_exception, EXC_XFER_EE)
736 EXCEPTION(0x2d00, Trap_2d, unknown_exception, EXC_XFER_EE)
737 EXCEPTION(0x2e00, Trap_2e, unknown_exception, EXC_XFER_EE)
738 EXCEPTION(0x2f00, MOLTrampoline, unknown_exception, EXC_XFER_EE_LITE)
739
740 .globl mol_trampoline
741 .set mol_trampoline, i0x2f00
742 EXPORT_SYMBOL(mol_trampoline)
743
744 . = 0x3000
745
746 AltiVecUnavailable:
747 EXCEPTION_PROLOG
748 #ifdef CONFIG_ALTIVEC
749 beq 1f
750 bl load_up_altivec /* if from user, just load it up */
751 b fast_exception_return
752 #endif /* CONFIG_ALTIVEC */
753 1: addi r3,r1,STACK_FRAME_OVERHEAD
754 EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception)
755
756 PerformanceMonitor:
757 EXCEPTION_PROLOG
758 addi r3,r1,STACK_FRAME_OVERHEAD
759 EXC_XFER_STD(0xf00, performance_monitor_exception)
760
761
762 /*
763 * This code is jumped to from the startup code to copy
764 * the kernel image to physical address PHYSICAL_START.
765 */
766 relocate_kernel:
767 addis r9,r26,klimit@ha /* fetch klimit */
768 lwz r25,klimit@l(r9)
769 addis r25,r25,-KERNELBASE@h
770 lis r3,PHYSICAL_START@h /* Destination base address */
771 li r6,0 /* Destination offset */
772 li r5,0x4000 /* # bytes of memory to copy */
773 bl copy_and_flush /* copy the first 0x4000 bytes */
774 addi r0,r3,4f@l /* jump to the address of 4f */
775 mtctr r0 /* in copy and do the rest. */
776 bctr /* jump to the copy */
777 4: mr r5,r25
778 bl copy_and_flush /* copy the rest */
779 b turn_on_mmu
780
781 /*
782 * Copy routine used to copy the kernel to start at physical address 0
783 * and flush and invalidate the caches as needed.
784 * r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset
785 * on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5.
786 */
787 _ENTRY(copy_and_flush)
788 addi r5,r5,-4
789 addi r6,r6,-4
790 4: li r0,L1_CACHE_BYTES/4
791 mtctr r0
792 3: addi r6,r6,4 /* copy a cache line */
793 lwzx r0,r6,r4
794 stwx r0,r6,r3
795 bdnz 3b
796 dcbst r6,r3 /* write it to memory */
797 sync
798 icbi r6,r3 /* flush the icache line */
799 cmplw 0,r6,r5
800 blt 4b
801 sync /* additional sync needed on g4 */
802 isync
803 addi r5,r5,4
804 addi r6,r6,4
805 blr
806
807 #ifdef CONFIG_SMP
808 .globl __secondary_start_mpc86xx
809 __secondary_start_mpc86xx:
810 mfspr r3, SPRN_PIR
811 stw r3, __secondary_hold_acknowledge@l(0)
812 mr r24, r3 /* cpu # */
813 b __secondary_start
814
815 .globl __secondary_start_pmac_0
816 __secondary_start_pmac_0:
817 /* NB the entries for cpus 0, 1, 2 must each occupy 8 bytes. */
818 li r24,0
819 b 1f
820 li r24,1
821 b 1f
822 li r24,2
823 b 1f
824 li r24,3
825 1:
826 /* on powersurge, we come in here with IR=0 and DR=1, and DBAT 0
827 set to map the 0xf0000000 - 0xffffffff region */
828 mfmsr r0
829 rlwinm r0,r0,0,28,26 /* clear DR (0x10) */
830 SYNC
831 mtmsr r0
832 isync
833
834 .globl __secondary_start
835 __secondary_start:
836 /* Copy some CPU settings from CPU 0 */
837 bl __restore_cpu_setup
838
839 lis r3,-KERNELBASE@h
840 mr r4,r24
841 bl call_setup_cpu /* Call setup_cpu for this CPU */
842 #ifdef CONFIG_6xx
843 lis r3,-KERNELBASE@h
844 bl init_idle_6xx
845 #endif /* CONFIG_6xx */
846
847 /* get current_thread_info and current */
848 lis r1,secondary_ti@ha
849 tophys(r1,r1)
850 lwz r1,secondary_ti@l(r1)
851 tophys(r2,r1)
852 lwz r2,TI_TASK(r2)
853
854 /* stack */
855 addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
856 li r0,0
857 tophys(r3,r1)
858 stw r0,0(r3)
859
860 /* load up the MMU */
861 bl load_up_mmu
862
863 /* ptr to phys current thread */
864 tophys(r4,r2)
865 addi r4,r4,THREAD /* phys address of our thread_struct */
866 mtspr SPRN_SPRG_THREAD,r4
867 li r3,0
868 mtspr SPRN_SPRG_RTAS,r3 /* 0 => not in RTAS */
869
870 /* enable MMU and jump to start_secondary */
871 li r4,MSR_KERNEL
872 FIX_SRR1(r4,r5)
873 lis r3,start_secondary@h
874 ori r3,r3,start_secondary@l
875 mtspr SPRN_SRR0,r3
876 mtspr SPRN_SRR1,r4
877 SYNC
878 RFI
879 #endif /* CONFIG_SMP */
880
881 #ifdef CONFIG_KVM_BOOK3S_HANDLER
882 #include "../kvm/book3s_rmhandlers.S"
883 #endif
884
885 /*
886 * Those generic dummy functions are kept for CPUs not
887 * included in CONFIG_6xx
888 */
889 #if !defined(CONFIG_6xx)
890 _ENTRY(__save_cpu_setup)
891 blr
892 _ENTRY(__restore_cpu_setup)
893 blr
894 #endif /* !defined(CONFIG_6xx) */
895
896
897 /*
898 * Load stuff into the MMU. Intended to be called with
899 * IR=0 and DR=0.
900 */
901 load_up_mmu:
902 sync /* Force all PTE updates to finish */
903 isync
904 tlbia /* Clear all TLB entries */
905 sync /* wait for tlbia/tlbie to finish */
906 TLBSYNC /* ... on all CPUs */
907 /* Load the SDR1 register (hash table base & size) */
908 lis r6,_SDR1@ha
909 tophys(r6,r6)
910 lwz r6,_SDR1@l(r6)
911 mtspr SPRN_SDR1,r6
912 li r0,16 /* load up segment register values */
913 mtctr r0 /* for context 0 */
914 lis r3,0x2000 /* Ku = 1, VSID = 0 */
915 li r4,0
916 3: mtsrin r3,r4
917 addi r3,r3,0x111 /* increment VSID */
918 addis r4,r4,0x1000 /* address of next segment */
919 bdnz 3b
920
921 /* Load the BAT registers with the values set up by MMU_init.
922 MMU_init takes care of whether we're on a 601 or not. */
923 mfpvr r3
924 srwi r3,r3,16
925 cmpwi r3,1
926 lis r3,BATS@ha
927 addi r3,r3,BATS@l
928 tophys(r3,r3)
929 LOAD_BAT(0,r3,r4,r5)
930 LOAD_BAT(1,r3,r4,r5)
931 LOAD_BAT(2,r3,r4,r5)
932 LOAD_BAT(3,r3,r4,r5)
933 BEGIN_MMU_FTR_SECTION
934 LOAD_BAT(4,r3,r4,r5)
935 LOAD_BAT(5,r3,r4,r5)
936 LOAD_BAT(6,r3,r4,r5)
937 LOAD_BAT(7,r3,r4,r5)
938 END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
939 blr
940
941 /*
942 * This is where the main kernel code starts.
943 */
944 start_here:
945 /* ptr to current */
946 lis r2,init_task@h
947 ori r2,r2,init_task@l
948 /* Set up for using our exception vectors */
949 /* ptr to phys current thread */
950 tophys(r4,r2)
951 addi r4,r4,THREAD /* init task's THREAD */
952 mtspr SPRN_SPRG_THREAD,r4
953 li r3,0
954 mtspr SPRN_SPRG_RTAS,r3 /* 0 => not in RTAS */
955
956 /* stack */
957 lis r1,init_thread_union@ha
958 addi r1,r1,init_thread_union@l
959 li r0,0
960 stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
961 /*
962 * Do early platform-specific initialization,
963 * and set up the MMU.
964 */
965 li r3,0
966 mr r4,r31
967 bl machine_init
968 bl __save_cpu_setup
969 bl MMU_init
970
971 /*
972 * Go back to running unmapped so we can load up new values
973 * for SDR1 (hash table pointer) and the segment registers
974 * and change to using our exception vectors.
975 */
976 lis r4,2f@h
977 ori r4,r4,2f@l
978 tophys(r4,r4)
979 li r3,MSR_KERNEL & ~(MSR_IR|MSR_DR)
980 FIX_SRR1(r3,r5)
981 mtspr SPRN_SRR0,r4
982 mtspr SPRN_SRR1,r3
983 SYNC
984 RFI
985 /* Load up the kernel context */
986 2: bl load_up_mmu
987
988 #ifdef CONFIG_BDI_SWITCH
989 /* Add helper information for the Abatron bdiGDB debugger.
990 * We do this here because we know the mmu is disabled, and
991 * will be enabled for real in just a few instructions.
992 */
993 lis r5, abatron_pteptrs@h
994 ori r5, r5, abatron_pteptrs@l
995 stw r5, 0xf0(r0) /* This much match your Abatron config */
996 lis r6, swapper_pg_dir@h
997 ori r6, r6, swapper_pg_dir@l
998 tophys(r5, r5)
999 stw r6, 0(r5)
1000 #endif /* CONFIG_BDI_SWITCH */
1001
1002 /* Now turn on the MMU for real! */
1003 li r4,MSR_KERNEL
1004 FIX_SRR1(r4,r5)
1005 lis r3,start_kernel@h
1006 ori r3,r3,start_kernel@l
1007 mtspr SPRN_SRR0,r3
1008 mtspr SPRN_SRR1,r4
1009 SYNC
1010 RFI
1011
1012 /*
1013 * void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
1014 *
1015 * Set up the segment registers for a new context.
1016 */
1017 _ENTRY(switch_mmu_context)
1018 lwz r3,MMCONTEXTID(r4)
1019 cmpwi cr0,r3,0
1020 blt- 4f
1021 mulli r3,r3,897 /* multiply context by skew factor */
1022 rlwinm r3,r3,4,8,27 /* VSID = (context & 0xfffff) << 4 */
1023 addis r3,r3,0x6000 /* Set Ks, Ku bits */
1024 li r0,NUM_USER_SEGMENTS
1025 mtctr r0
1026
1027 #ifdef CONFIG_BDI_SWITCH
1028 /* Context switch the PTE pointer for the Abatron BDI2000.
1029 * The PGDIR is passed as second argument.
1030 */
1031 lwz r4,MM_PGD(r4)
1032 lis r5, KERNELBASE@h
1033 lwz r5, 0xf0(r5)
1034 stw r4, 0x4(r5)
1035 #endif
1036 li r4,0
1037 isync
1038 3:
1039 mtsrin r3,r4
1040 addi r3,r3,0x111 /* next VSID */
1041 rlwinm r3,r3,0,8,3 /* clear out any overflow from VSID field */
1042 addis r4,r4,0x1000 /* address of next segment */
1043 bdnz 3b
1044 sync
1045 isync
1046 blr
1047 4: trap
1048 EMIT_BUG_ENTRY 4b,__FILE__,__LINE__,0
1049 blr
1050 EXPORT_SYMBOL(switch_mmu_context)
1051
1052 /*
1053 * An undocumented "feature" of 604e requires that the v bit
1054 * be cleared before changing BAT values.
1055 *
1056 * Also, newer IBM firmware does not clear bat3 and 4 so
1057 * this makes sure it's done.
1058 * -- Cort
1059 */
1060 clear_bats:
1061 li r10,0
1062 mfspr r9,SPRN_PVR
1063 rlwinm r9,r9,16,16,31 /* r9 = 1 for 601, 4 for 604 */
1064 cmpwi r9, 1
1065 beq 1f
1066
1067 mtspr SPRN_DBAT0U,r10
1068 mtspr SPRN_DBAT0L,r10
1069 mtspr SPRN_DBAT1U,r10
1070 mtspr SPRN_DBAT1L,r10
1071 mtspr SPRN_DBAT2U,r10
1072 mtspr SPRN_DBAT2L,r10
1073 mtspr SPRN_DBAT3U,r10
1074 mtspr SPRN_DBAT3L,r10
1075 1:
1076 mtspr SPRN_IBAT0U,r10
1077 mtspr SPRN_IBAT0L,r10
1078 mtspr SPRN_IBAT1U,r10
1079 mtspr SPRN_IBAT1L,r10
1080 mtspr SPRN_IBAT2U,r10
1081 mtspr SPRN_IBAT2L,r10
1082 mtspr SPRN_IBAT3U,r10
1083 mtspr SPRN_IBAT3L,r10
1084 BEGIN_MMU_FTR_SECTION
1085 /* Here's a tweak: at this point, CPU setup have
1086 * not been called yet, so HIGH_BAT_EN may not be
1087 * set in HID0 for the 745x processors. However, it
1088 * seems that doesn't affect our ability to actually
1089 * write to these SPRs.
1090 */
1091 mtspr SPRN_DBAT4U,r10
1092 mtspr SPRN_DBAT4L,r10
1093 mtspr SPRN_DBAT5U,r10
1094 mtspr SPRN_DBAT5L,r10
1095 mtspr SPRN_DBAT6U,r10
1096 mtspr SPRN_DBAT6L,r10
1097 mtspr SPRN_DBAT7U,r10
1098 mtspr SPRN_DBAT7L,r10
1099 mtspr SPRN_IBAT4U,r10
1100 mtspr SPRN_IBAT4L,r10
1101 mtspr SPRN_IBAT5U,r10
1102 mtspr SPRN_IBAT5L,r10
1103 mtspr SPRN_IBAT6U,r10
1104 mtspr SPRN_IBAT6L,r10
1105 mtspr SPRN_IBAT7U,r10
1106 mtspr SPRN_IBAT7L,r10
1107 END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
1108 blr
1109
1110 flush_tlbs:
1111 lis r10, 0x40
1112 1: addic. r10, r10, -0x1000
1113 tlbie r10
1114 bgt 1b
1115 sync
1116 blr
1117
1118 mmu_off:
1119 addi r4, r3, __after_mmu_off - _start
1120 mfmsr r3
1121 andi. r0,r3,MSR_DR|MSR_IR /* MMU enabled? */
1122 beqlr
1123 andc r3,r3,r0
1124 mtspr SPRN_SRR0,r4
1125 mtspr SPRN_SRR1,r3
1126 sync
1127 RFI
1128
1129 /*
1130 * On 601, we use 3 BATs to map up to 24M of RAM at _PAGE_OFFSET
1131 * (we keep one for debugging) and on others, we use one 256M BAT.
1132 */
1133 initial_bats:
1134 lis r11,PAGE_OFFSET@h
1135 mfspr r9,SPRN_PVR
1136 rlwinm r9,r9,16,16,31 /* r9 = 1 for 601, 4 for 604 */
1137 cmpwi 0,r9,1
1138 bne 4f
1139 ori r11,r11,4 /* set up BAT registers for 601 */
1140 li r8,0x7f /* valid, block length = 8MB */
1141 mtspr SPRN_IBAT0U,r11 /* N.B. 601 has valid bit in */
1142 mtspr SPRN_IBAT0L,r8 /* lower BAT register */
1143 addis r11,r11,0x800000@h
1144 addis r8,r8,0x800000@h
1145 mtspr SPRN_IBAT1U,r11
1146 mtspr SPRN_IBAT1L,r8
1147 addis r11,r11,0x800000@h
1148 addis r8,r8,0x800000@h
1149 mtspr SPRN_IBAT2U,r11
1150 mtspr SPRN_IBAT2L,r8
1151 isync
1152 blr
1153
1154 4: tophys(r8,r11)
1155 #ifdef CONFIG_SMP
1156 ori r8,r8,0x12 /* R/W access, M=1 */
1157 #else
1158 ori r8,r8,2 /* R/W access */
1159 #endif /* CONFIG_SMP */
1160 ori r11,r11,BL_256M<<2|0x2 /* set up BAT registers for 604 */
1161
1162 mtspr SPRN_DBAT0L,r8 /* N.B. 6xx (not 601) have valid */
1163 mtspr SPRN_DBAT0U,r11 /* bit in upper BAT register */
1164 mtspr SPRN_IBAT0L,r8
1165 mtspr SPRN_IBAT0U,r11
1166 isync
1167 blr
1168
1169
1170 #ifdef CONFIG_BOOTX_TEXT
1171 setup_disp_bat:
1172 /*
1173 * setup the display bat prepared for us in prom.c
1174 */
1175 mflr r8
1176 bl reloc_offset
1177 mtlr r8
1178 addis r8,r3,disp_BAT@ha
1179 addi r8,r8,disp_BAT@l
1180 cmpwi cr0,r8,0
1181 beqlr
1182 lwz r11,0(r8)
1183 lwz r8,4(r8)
1184 mfspr r9,SPRN_PVR
1185 rlwinm r9,r9,16,16,31 /* r9 = 1 for 601, 4 for 604 */
1186 cmpwi 0,r9,1
1187 beq 1f
1188 mtspr SPRN_DBAT3L,r8
1189 mtspr SPRN_DBAT3U,r11
1190 blr
1191 1: mtspr SPRN_IBAT3L,r8
1192 mtspr SPRN_IBAT3U,r11
1193 blr
1194 #endif /* CONFIG_BOOTX_TEXT */
1195
1196 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
1197 setup_cpm_bat:
1198 lis r8, 0xf000
1199 ori r8, r8, 0x002a
1200 mtspr SPRN_DBAT1L, r8
1201
1202 lis r11, 0xf000
1203 ori r11, r11, (BL_1M << 2) | 2
1204 mtspr SPRN_DBAT1U, r11
1205
1206 blr
1207 #endif
1208
1209 #ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
1210 setup_usbgecko_bat:
1211 /* prepare a BAT for early io */
1212 #if defined(CONFIG_GAMECUBE)
1213 lis r8, 0x0c00
1214 #elif defined(CONFIG_WII)
1215 lis r8, 0x0d00
1216 #else
1217 #error Invalid platform for USB Gecko based early debugging.
1218 #endif
1219 /*
1220 * The virtual address used must match the virtual address
1221 * associated to the fixmap entry FIX_EARLY_DEBUG_BASE.
1222 */
1223 lis r11, 0xfffe /* top 128K */
1224 ori r8, r8, 0x002a /* uncached, guarded ,rw */
1225 ori r11, r11, 0x2 /* 128K, Vs=1, Vp=0 */
1226 mtspr SPRN_DBAT1L, r8
1227 mtspr SPRN_DBAT1U, r11
1228 blr
1229 #endif
1230
1231 #ifdef CONFIG_8260
1232 /* Jump into the system reset for the rom.
1233 * We first disable the MMU, and then jump to the ROM reset address.
1234 *
1235 * r3 is the board info structure, r4 is the location for starting.
1236 * I use this for building a small kernel that can load other kernels,
1237 * rather than trying to write or rely on a rom monitor that can tftp load.
1238 */
1239 .globl m8260_gorom
1240 m8260_gorom:
1241 mfmsr r0
1242 rlwinm r0,r0,0,17,15 /* clear MSR_EE in r0 */
1243 sync
1244 mtmsr r0
1245 sync
1246 mfspr r11, SPRN_HID0
1247 lis r10, 0
1248 ori r10,r10,HID0_ICE|HID0_DCE
1249 andc r11, r11, r10
1250 mtspr SPRN_HID0, r11
1251 isync
1252 li r5, MSR_ME|MSR_RI
1253 lis r6,2f@h
1254 addis r6,r6,-KERNELBASE@h
1255 ori r6,r6,2f@l
1256 mtspr SPRN_SRR0,r6
1257 mtspr SPRN_SRR1,r5
1258 isync
1259 sync
1260 rfi
1261 2:
1262 mtlr r4
1263 blr
1264 #endif
1265
1266
1267 /*
1268 * We put a few things here that have to be page-aligned.
1269 * This stuff goes at the beginning of the data segment,
1270 * which is page-aligned.
1271 */
1272 .data
1273 .globl sdata
1274 sdata:
1275 .globl empty_zero_page
1276 empty_zero_page:
1277 .space 4096
1278 EXPORT_SYMBOL(empty_zero_page)
1279
1280 .globl swapper_pg_dir
1281 swapper_pg_dir:
1282 .space PGD_TABLE_SIZE
1283
1284 .globl intercept_table
1285 intercept_table:
1286 .long 0, 0, i0x200, i0x300, i0x400, 0, i0x600, i0x700
1287 .long i0x800, 0, 0, 0, 0, i0xd00, 0, 0
1288 .long 0, 0, 0, i0x1300, 0, 0, 0, 0
1289 .long 0, 0, 0, 0, 0, 0, 0, 0
1290 .long 0, 0, 0, 0, 0, 0, 0, 0
1291 .long 0, 0, 0, 0, 0, 0, 0, 0
1292 EXPORT_SYMBOL(intercept_table)
1293
1294 /* Room for two PTE pointers, usually the kernel and current user pointers
1295 * to their respective root page table.
1296 */
1297 abatron_pteptrs:
1298 .space 8