xref: /linux/arch/powerpc/kernel/head_book3s_32.S (revision 3ea5eb68b9d624935108b5e696859304edfac202)
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 *  PowerPC version
4 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5 *
6 *  Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
7 *    Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
8 *  Adapted for Power Macintosh by Paul Mackerras.
9 *  Low-level exception handlers and MMU support
10 *  rewritten by Paul Mackerras.
11 *    Copyright (C) 1996 Paul Mackerras.
12 *  MPC8xx modifications Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
13 *
14 *  This file contains the low-level support and setup for the
15 *  PowerPC platform, including trap and interrupt dispatch.
16 *  (The PPC 8xx embedded CPUs use head_8xx.S instead.)
17 */
18
19#include <linux/init.h>
20#include <linux/pgtable.h>
21#include <linux/linkage.h>
22
23#include <asm/reg.h>
24#include <asm/page.h>
25#include <asm/mmu.h>
26#include <asm/cputable.h>
27#include <asm/cache.h>
28#include <asm/thread_info.h>
29#include <asm/ppc_asm.h>
30#include <asm/asm-offsets.h>
31#include <asm/ptrace.h>
32#include <asm/bug.h>
33#include <asm/kvm_book3s_asm.h>
34#include <asm/feature-fixups.h>
35#include <asm/interrupt.h>
36
37#include "head_32.h"
38
39#define LOAD_BAT(n, reg, RA, RB)	\
40	/* see the comment for clear_bats() -- Cort */ \
41	li	RA,0;			\
42	mtspr	SPRN_IBAT##n##U,RA;	\
43	mtspr	SPRN_DBAT##n##U,RA;	\
44	lwz	RA,(n*16)+0(reg);	\
45	lwz	RB,(n*16)+4(reg);	\
46	mtspr	SPRN_IBAT##n##U,RA;	\
47	mtspr	SPRN_IBAT##n##L,RB;	\
48	lwz	RA,(n*16)+8(reg);	\
49	lwz	RB,(n*16)+12(reg);	\
50	mtspr	SPRN_DBAT##n##U,RA;	\
51	mtspr	SPRN_DBAT##n##L,RB
52
53	__HEAD
54_GLOBAL(_stext);
55
56/*
57 * _start is defined this way because the XCOFF loader in the OpenFirmware
58 * on the powermac expects the entry point to be a procedure descriptor.
59 */
60_GLOBAL(_start);
61	/*
62	 * These are here for legacy reasons, the kernel used to
63	 * need to look like a coff function entry for the pmac
64	 * but we're always started by some kind of bootloader now.
65	 *  -- Cort
66	 */
67	nop	/* used by __secondary_hold on prep (mtx) and chrp smp */
68	nop	/* used by __secondary_hold on prep (mtx) and chrp smp */
69	nop
70
71/* PMAC
72 * Enter here with the kernel text, data and bss loaded starting at
73 * 0, running with virtual == physical mapping.
74 * r5 points to the prom entry point (the client interface handler
75 * address).  Address translation is turned on, with the prom
76 * managing the hash table.  Interrupts are disabled.  The stack
77 * pointer (r1) points to just below the end of the half-meg region
78 * from 0x380000 - 0x400000, which is mapped in already.
79 *
80 * If we are booted from MacOS via BootX, we enter with the kernel
81 * image loaded somewhere, and the following values in registers:
82 *  r3: 'BooX' (0x426f6f58)
83 *  r4: virtual address of boot_infos_t
84 *  r5: 0
85 *
86 * PREP
87 * This is jumped to on prep systems right after the kernel is relocated
88 * to its proper place in memory by the boot loader.  The expected layout
89 * of the regs is:
90 *   r3: ptr to residual data
91 *   r4: initrd_start or if no initrd then 0
92 *   r5: initrd_end - unused if r4 is 0
93 *   r6: Start of command line string
94 *   r7: End of command line string
95 *
96 * This just gets a minimal mmu environment setup so we can call
97 * start_here() to do the real work.
98 * -- Cort
99 */
100
101	.globl	__start
102__start:
103/*
104 * We have to do any OF calls before we map ourselves to KERNELBASE,
105 * because OF may have I/O devices mapped into that area
106 * (particularly on CHRP).
107 */
108	cmpwi	0,r5,0
109	beq	1f
110
111#ifdef CONFIG_PPC_OF_BOOT_TRAMPOLINE
112	/* find out where we are now */
113	bcl	20,31,$+4
1140:	mflr	r8			/* r8 = runtime addr here */
115	addis	r8,r8,(_stext - 0b)@ha
116	addi	r8,r8,(_stext - 0b)@l	/* current runtime base addr */
117	bl	prom_init
118#endif /* CONFIG_PPC_OF_BOOT_TRAMPOLINE */
119
120	/* We never return. We also hit that trap if trying to boot
121	 * from OF while CONFIG_PPC_OF_BOOT_TRAMPOLINE isn't selected */
122	trap
123
124/*
125 * Check for BootX signature when supporting PowerMac and branch to
126 * appropriate trampoline if it's present
127 */
128#ifdef CONFIG_PPC_PMAC
1291:	lis	r31,0x426f
130	ori	r31,r31,0x6f58
131	cmpw	0,r3,r31
132	bne	1f
133	bl	bootx_init
134	trap
135#endif /* CONFIG_PPC_PMAC */
136
1371:	mr	r31,r3			/* save device tree ptr */
138	li	r24,0			/* cpu # */
139
140/*
141 * early_init() does the early machine identification and does
142 * the necessary low-level setup and clears the BSS
143 *  -- Cort <cort@fsmlabs.com>
144 */
145	bl	early_init
146
147/* Switch MMU off, clear BATs and flush TLB. At this point, r3 contains
148 * the physical address we are running at, returned by early_init()
149 */
150 	bl	mmu_off
151__after_mmu_off:
152	bl	clear_bats
153	bl	flush_tlbs
154
155	bl	initial_bats
156	bl	load_segment_registers
157	bl	reloc_offset
158	bl	early_hash_table
159#if defined(CONFIG_BOOTX_TEXT)
160	bl	setup_disp_bat
161#endif
162#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
163	bl	setup_cpm_bat
164#endif
165#ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
166	bl	setup_usbgecko_bat
167#endif
168
169/*
170 * Call setup_cpu for CPU 0 and initialize 6xx Idle
171 */
172	bl	reloc_offset
173	li	r24,0			/* cpu# */
174	bl	call_setup_cpu		/* Call setup_cpu for this CPU */
175	bl	reloc_offset
176	bl	init_idle_6xx
177
178
179/*
180 * We need to run with _start at physical address 0.
181 * On CHRP, we are loaded at 0x10000 since OF on CHRP uses
182 * the exception vectors at 0 (and therefore this copy
183 * overwrites OF's exception vectors with our own).
184 * The MMU is off at this point.
185 */
186	bl	reloc_offset
187	mr	r26,r3
188	addis	r4,r3,KERNELBASE@h	/* current address of _start */
189	lis	r5,PHYSICAL_START@h
190	cmplw	0,r4,r5			/* already running at PHYSICAL_START? */
191	bne	relocate_kernel
192/*
193 * we now have the 1st 16M of ram mapped with the bats.
194 * prep needs the mmu to be turned on here, but pmac already has it on.
195 * this shouldn't bother the pmac since it just gets turned on again
196 * as we jump to our code at KERNELBASE. -- Cort
197 * Actually no, pmac doesn't have it on any more. BootX enters with MMU
198 * off, and in other cases, we now turn it off before changing BATs above.
199 */
200turn_on_mmu:
201	mfmsr	r0
202	ori	r0,r0,MSR_DR|MSR_IR|MSR_RI
203	mtspr	SPRN_SRR1,r0
204	lis	r0,start_here@h
205	ori	r0,r0,start_here@l
206	mtspr	SPRN_SRR0,r0
207	rfi				/* enables MMU */
208
209/*
210 * We need __secondary_hold as a place to hold the other cpus on
211 * an SMP machine, even when we are running a UP kernel.
212 */
213	. = 0xc0			/* for prep bootloader */
214	li	r3,1			/* MTX only has 1 cpu */
215	.globl	__secondary_hold
216__secondary_hold:
217	/* tell the master we're here */
218	stw	r3,__secondary_hold_acknowledge@l(0)
219#ifdef CONFIG_SMP
220100:	lwz	r4,0(0)
221	/* wait until we're told to start */
222	cmpw	0,r4,r3
223	bne	100b
224	/* our cpu # was at addr 0 - go */
225	mr	r24,r3			/* cpu # */
226	b	__secondary_start
227#else
228	b	.
229#endif /* CONFIG_SMP */
230
231	.globl	__secondary_hold_spinloop
232__secondary_hold_spinloop:
233	.long	0
234	.globl	__secondary_hold_acknowledge
235__secondary_hold_acknowledge:
236	.long	-1
237
238/* System reset */
239/* core99 pmac starts the seconary here by changing the vector, and
240   putting it back to what it was (unknown_async_exception) when done.  */
241	EXCEPTION(INTERRUPT_SYSTEM_RESET, Reset, unknown_async_exception)
242
243/* Machine check */
244/*
245 * On CHRP, this is complicated by the fact that we could get a
246 * machine check inside RTAS, and we have no guarantee that certain
247 * critical registers will have the values we expect.  The set of
248 * registers that might have bad values includes all the GPRs
249 * and all the BATs.  We indicate that we are in RTAS by putting
250 * a non-zero value, the address of the exception frame to use,
251 * in thread.rtas_sp.  The machine check handler checks thread.rtas_sp
252 * and uses its value if it is non-zero.
253 * (Other exception handlers assume that r1 is a valid kernel stack
254 * pointer when we take an exception from supervisor mode.)
255 *	-- paulus.
256 */
257	START_EXCEPTION(INTERRUPT_MACHINE_CHECK, MachineCheck)
258	EXCEPTION_PROLOG_0
259#ifdef CONFIG_PPC_CHRP
260	mtspr	SPRN_SPRG_SCRATCH2,r1
261	mfspr	r1, SPRN_SPRG_THREAD
262	lwz	r1, RTAS_SP(r1)
263	cmpwi	cr1, r1, 0
264	bne	cr1, 7f
265	mfspr	r1, SPRN_SPRG_SCRATCH2
266#endif /* CONFIG_PPC_CHRP */
267	EXCEPTION_PROLOG_1
2687:	EXCEPTION_PROLOG_2 0x200 MachineCheck
269#ifdef CONFIG_PPC_CHRP
270	beq	cr1, 1f
271	twi	31, 0, 0
272#endif
2731:	prepare_transfer_to_handler
274	bl	machine_check_exception
275	b	interrupt_return
276
277/* Data access exception. */
278	START_EXCEPTION(INTERRUPT_DATA_STORAGE, DataAccess)
279#ifdef CONFIG_PPC_BOOK3S_604
280BEGIN_MMU_FTR_SECTION
281	mtspr	SPRN_SPRG_SCRATCH2,r10
282	mfspr	r10, SPRN_SPRG_THREAD
283	stw	r11, THR11(r10)
284	mfspr	r10, SPRN_DSISR
285	mfcr	r11
286	andis.	r10, r10, (DSISR_BAD_FAULT_32S | DSISR_DABRMATCH)@h
287	mfspr	r10, SPRN_SPRG_THREAD
288	beq	hash_page_dsi
289.Lhash_page_dsi_cont:
290	mtcr	r11
291	lwz	r11, THR11(r10)
292	mfspr	r10, SPRN_SPRG_SCRATCH2
293MMU_FTR_SECTION_ELSE
294	b	1f
295ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_HPTE_TABLE)
296#endif
2971:	EXCEPTION_PROLOG_0 handle_dar_dsisr=1
298	EXCEPTION_PROLOG_1
299	EXCEPTION_PROLOG_2 INTERRUPT_DATA_STORAGE DataAccess handle_dar_dsisr=1
300	prepare_transfer_to_handler
301	lwz	r5, _DSISR(r1)
302	andis.	r0, r5, DSISR_DABRMATCH@h
303	bne-	1f
304	bl	do_page_fault
305	b	interrupt_return
3061:	bl	do_break
307	REST_NVGPRS(r1)
308	b	interrupt_return
309
310
311/* Instruction access exception. */
312	START_EXCEPTION(INTERRUPT_INST_STORAGE, InstructionAccess)
313	mtspr	SPRN_SPRG_SCRATCH0,r10
314	mtspr	SPRN_SPRG_SCRATCH1,r11
315	mfspr	r10, SPRN_SPRG_THREAD
316	mfspr	r11, SPRN_SRR0
317	stw	r11, SRR0(r10)
318	mfspr	r11, SPRN_SRR1		/* check whether user or kernel */
319	stw	r11, SRR1(r10)
320	mfcr	r10
321#ifdef CONFIG_PPC_BOOK3S_604
322BEGIN_MMU_FTR_SECTION
323	andis.	r11, r11, SRR1_ISI_NOPT@h	/* no pte found? */
324	bne	hash_page_isi
325.Lhash_page_isi_cont:
326	mfspr	r11, SPRN_SRR1		/* check whether user or kernel */
327END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
328#endif
329	andi.	r11, r11, MSR_PR
330
331	EXCEPTION_PROLOG_1
332	EXCEPTION_PROLOG_2 INTERRUPT_INST_STORAGE InstructionAccess
333	andis.	r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
334	stw	r5, _DSISR(r11)
335	stw	r12, _DAR(r11)
336	prepare_transfer_to_handler
337	bl	do_page_fault
338	b	interrupt_return
339
340/* External interrupt */
341	EXCEPTION(INTERRUPT_EXTERNAL, HardwareInterrupt, do_IRQ)
342
343/* Alignment exception */
344	START_EXCEPTION(INTERRUPT_ALIGNMENT, Alignment)
345	EXCEPTION_PROLOG INTERRUPT_ALIGNMENT Alignment handle_dar_dsisr=1
346	prepare_transfer_to_handler
347	bl	alignment_exception
348	REST_NVGPRS(r1)
349	b	interrupt_return
350
351/* Program check exception */
352	START_EXCEPTION(INTERRUPT_PROGRAM, ProgramCheck)
353	EXCEPTION_PROLOG INTERRUPT_PROGRAM ProgramCheck
354	prepare_transfer_to_handler
355	bl	program_check_exception
356	REST_NVGPRS(r1)
357	b	interrupt_return
358
359/* Floating-point unavailable */
360	START_EXCEPTION(0x800, FPUnavailable)
361#ifdef CONFIG_PPC_FPU
362BEGIN_FTR_SECTION
363/*
364 * Certain Freescale cores don't have a FPU and treat fp instructions
365 * as a FP Unavailable exception.  Redirect to illegal/emulation handling.
366 */
367	b 	ProgramCheck
368END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
369	EXCEPTION_PROLOG INTERRUPT_FP_UNAVAIL FPUnavailable
370	beq	1f
371	bl	load_up_fpu		/* if from user, just load it up */
372	b	fast_exception_return
3731:	prepare_transfer_to_handler
374	bl	kernel_fp_unavailable_exception
375	b	interrupt_return
376#else
377	b 	ProgramCheck
378#endif
379
380/* Decrementer */
381	EXCEPTION(INTERRUPT_DECREMENTER, Decrementer, timer_interrupt)
382
383	EXCEPTION(0xa00, Trap_0a, unknown_exception)
384	EXCEPTION(0xb00, Trap_0b, unknown_exception)
385
386/* System call */
387	START_EXCEPTION(INTERRUPT_SYSCALL, SystemCall)
388	SYSCALL_ENTRY	INTERRUPT_SYSCALL
389
390	EXCEPTION(INTERRUPT_TRACE, SingleStep, single_step_exception)
391	EXCEPTION(0xe00, Trap_0e, unknown_exception)
392
393/*
394 * The Altivec unavailable trap is at 0x0f20.  Foo.
395 * We effectively remap it to 0x3000.
396 * We include an altivec unavailable exception vector even if
397 * not configured for Altivec, so that you can't panic a
398 * non-altivec kernel running on a machine with altivec just
399 * by executing an altivec instruction.
400 */
401	START_EXCEPTION(INTERRUPT_PERFMON, PerformanceMonitorTrap)
402	b	PerformanceMonitor
403
404	START_EXCEPTION(INTERRUPT_ALTIVEC_UNAVAIL, AltiVecUnavailableTrap)
405	b	AltiVecUnavailable
406
407	__HEAD
408/*
409 * Handle TLB miss for instruction on 603/603e.
410 * Note: we get an alternate set of r0 - r3 to use automatically.
411 */
412	. = INTERRUPT_INST_TLB_MISS_603
413InstructionTLBMiss:
414	/* Get PTE (linux-style) and check access */
415	mfspr	r0,SPRN_IMISS
416	mfspr	r2, SPRN_SDR1
417	li	r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC
418	rlwinm	r2, r2, 28, 0xfffff000
419	rlwimi	r2,r0,12,20,29		/* insert top 10 bits of address */
420	lwz	r2,0(r2)		/* get pmd entry */
421#ifdef CONFIG_EXECMEM
422	rlwinm	r3, r0, 4, 0xf
423	subi	r3, r3, (TASK_SIZE >> 28) & 0xf
424#endif
425	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
426	beq-	InstructionAddressInvalid	/* return if no mapping */
427	rlwimi	r2,r0,22,20,29		/* insert next 10 bits of address */
428	lwz	r2,0(r2)		/* get linux-style pte */
429	andc.	r1,r1,r2		/* check access & ~permission */
430	bne-	InstructionAddressInvalid /* return if access not permitted */
431	/* Convert linux-style PTE to low word of PPC-style PTE */
432#ifdef CONFIG_EXECMEM
433	rlwimi	r2, r3, 1, 31, 31	/* userspace ? -> PP lsb */
434#endif
435	ori	r1, r1, 0xe06		/* clear out reserved bits */
436	andc	r1, r2, r1		/* PP = user? 1 : 0 */
437BEGIN_FTR_SECTION
438	rlwinm	r1,r1,0,~_PAGE_COHERENT	/* clear M (coherence not required) */
439END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
440	mtspr	SPRN_RPA,r1
441	tlbli	r0
442	mfspr	r3,SPRN_SRR1		/* Need to restore CR0 */
443	mtcrf	0x80,r3
444	rfi
445InstructionAddressInvalid:
446	mfspr	r3,SPRN_SRR1
447	rlwinm	r1,r3,9,6,6	/* Get load/store bit */
448
449	addis	r1,r1,0x2000
450	mtspr	SPRN_DSISR,r1	/* (shouldn't be needed) */
451	andi.	r2,r3,0xFFFF	/* Clear upper bits of SRR1 */
452	or	r2,r2,r1
453	mtspr	SPRN_SRR1,r2
454	mfspr	r1,SPRN_IMISS	/* Get failing address */
455	rlwinm.	r2,r2,0,31,31	/* Check for little endian access */
456	rlwimi	r2,r2,1,30,30	/* change 1 -> 3 */
457	xor	r1,r1,r2
458	mtspr	SPRN_DAR,r1	/* Set fault address */
459	mfmsr	r0		/* Restore "normal" registers */
460	xoris	r0,r0,MSR_TGPR>>16
461	mtcrf	0x80,r3		/* Restore CR0 */
462	mtmsr	r0
463	b	InstructionAccess
464
465/*
466 * Handle TLB miss for DATA Load operation on 603/603e
467 */
468	. = INTERRUPT_DATA_LOAD_TLB_MISS_603
469DataLoadTLBMiss:
470	/* Get PTE (linux-style) and check access */
471	mfspr	r0,SPRN_DMISS
472	mfspr	r2, SPRN_SDR1
473	rlwinm	r1, r2, 28, 0xfffff000
474	rlwimi	r1,r0,12,20,29		/* insert top 10 bits of address */
475	lwz	r2,0(r1)		/* get pmd entry */
476	rlwinm	r3, r0, 4, 0xf
477	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
478	subi	r3, r3, (TASK_SIZE >> 28) & 0xf
479	beq-	2f			/* bail if no mapping */
4801:	rlwimi	r2,r0,22,20,29		/* insert next 10 bits of address */
481	lwz	r2,0(r2)		/* get linux-style pte */
482	li	r1, _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_READ
483	andc.	r1,r1,r2		/* check access & ~permission */
484	bne-	DataAddressInvalid	/* return if access not permitted */
485	/* Convert linux-style PTE to low word of PPC-style PTE */
486	rlwinm	r1,r2,32-9,30,30	/* _PAGE_WRITE -> PP msb */
487	rlwimi	r2,r3,2,30,31		/* userspace ? -> PP */
488	rlwimi	r1,r2,32-3,24,24	/* _PAGE_WRITE -> _PAGE_DIRTY */
489	xori	r1,r1,_PAGE_DIRTY	/* clear dirty when not rw */
490	ori	r1,r1,0xe04		/* clear out reserved bits */
491	andc	r1,r2,r1		/* PP = user? rw? 1: 3: 0 */
492BEGIN_FTR_SECTION
493	rlwinm	r1,r1,0,~_PAGE_COHERENT	/* clear M (coherence not required) */
494END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
495	mtspr	SPRN_RPA,r1
496BEGIN_MMU_FTR_SECTION
497	li	r3,1
498	mfspr	r1,SPRN_SPRG_603_LRU
499	rlwinm	r2,r0,20,27,31		/* Get Address bits 15:19 */
500	slw	r3,r3,r2
501	xor	r1,r3,r1
502	srw	r3,r1,r2
503	mtspr   SPRN_SPRG_603_LRU,r1
504	mfspr	r2,SPRN_SRR1
505	rlwimi	r2,r3,31-14,14,14
506	mtspr   SPRN_SRR1,r2
507	mtcrf	0x80,r2
508	tlbld	r0
509	rfi
510MMU_FTR_SECTION_ELSE
511	mfspr	r2,SPRN_SRR1		/* Need to restore CR0 */
512	mtcrf	0x80,r2
513	tlbld	r0
514	rfi
515ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
516
5172:	lis     r2, (swapper_pg_dir - PAGE_OFFSET)@ha
518	addi    r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l        /* kernel page table */
519	rlwimi	r2,r0,12,20,29		/* insert top 10 bits of address */
520	lwz	r2,0(r2)		/* get pmd entry */
521	cmpwi	cr0,r2,0
522	beq-	DataAddressInvalid	/* return if no mapping */
523	stw	r2,0(r1)
524	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
525	b	1b
526DataAddressInvalid:
527	mfspr	r3,SPRN_SRR1
528	rlwinm	r1,r3,9,6,6	/* Get load/store bit */
529	addis	r1,r1,0x2000
530	mtspr	SPRN_DSISR,r1
531	andi.	r2,r3,0xFFFF	/* Clear upper bits of SRR1 */
532	mtspr	SPRN_SRR1,r2
533	mfspr	r1,SPRN_DMISS	/* Get failing address */
534	rlwinm.	r2,r2,0,31,31	/* Check for little endian access */
535	beq	20f		/* Jump if big endian */
536	xori	r1,r1,3
53720:	mtspr	SPRN_DAR,r1	/* Set fault address */
538	mfmsr	r0		/* Restore "normal" registers */
539	xoris	r0,r0,MSR_TGPR>>16
540	mtcrf	0x80,r3		/* Restore CR0 */
541	mtmsr	r0
542	b	DataAccess
543
544/*
545 * Handle TLB miss for DATA Store on 603/603e
546 */
547	. = INTERRUPT_DATA_STORE_TLB_MISS_603
548DataStoreTLBMiss:
549	/* Get PTE (linux-style) and check access */
550	mfspr	r0,SPRN_DMISS
551	mfspr	r2, SPRN_SDR1
552	rlwinm	r1, r2, 28, 0xfffff000
553	rlwimi	r1,r0,12,20,29		/* insert top 10 bits of address */
554	lwz	r2,0(r1)		/* get pmd entry */
555	rlwinm	r3, r0, 4, 0xf
556	rlwinm.	r2,r2,0,0,19		/* extract address of pte page */
557	subi	r3, r3, (TASK_SIZE >> 28) & 0xf
558	beq-	2f			/* bail if no mapping */
5591:
560	rlwimi	r2,r0,22,20,29		/* insert next 10 bits of address */
561	lwz	r2,0(r2)		/* get linux-style pte */
562	li	r1, _PAGE_RW | _PAGE_DIRTY | _PAGE_PRESENT | _PAGE_ACCESSED
563	andc.	r1,r1,r2		/* check access & ~permission */
564	bne-	DataAddressInvalid	/* return if access not permitted */
565	/* Convert linux-style PTE to low word of PPC-style PTE */
566	rlwimi	r2,r3,1,31,31		/* userspace ? -> PP lsb */
567	li	r1,0xe06		/* clear out reserved bits & PP msb */
568	andc	r1,r2,r1		/* PP = user? 1: 0 */
569BEGIN_FTR_SECTION
570	rlwinm	r1,r1,0,~_PAGE_COHERENT	/* clear M (coherence not required) */
571END_FTR_SECTION_IFCLR(CPU_FTR_NEED_COHERENT)
572	mtspr	SPRN_RPA,r1
573	mfspr	r2,SPRN_SRR1		/* Need to restore CR0 */
574	mtcrf	0x80,r2
575BEGIN_MMU_FTR_SECTION
576	li	r3,1
577	mfspr	r1,SPRN_SPRG_603_LRU
578	rlwinm	r2,r0,20,27,31		/* Get Address bits 15:19 */
579	slw	r3,r3,r2
580	xor	r1,r3,r1
581	srw	r3,r1,r2
582	mtspr   SPRN_SPRG_603_LRU,r1
583	mfspr	r2,SPRN_SRR1
584	rlwimi	r2,r3,31-14,14,14
585	mtspr   SPRN_SRR1,r2
586	mtcrf	0x80,r2
587	tlbld	r0
588	rfi
589MMU_FTR_SECTION_ELSE
590	mfspr	r2,SPRN_SRR1		/* Need to restore CR0 */
591	mtcrf	0x80,r2
592	tlbld	r0
593	rfi
594ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
595
5962:	lis     r2, (swapper_pg_dir - PAGE_OFFSET)@ha
597	addi    r2, r2, (swapper_pg_dir - PAGE_OFFSET)@l        /* kernel page table */
598	rlwimi	r2,r0,12,20,29		/* insert top 10 bits of address */
599	lwz	r2,0(r2)		/* get pmd entry */
600	cmpwi	cr0,r2,0
601	beq-	DataAddressInvalid	/* return if no mapping */
602	stw	r2,0(r1)
603	rlwinm	r2,r2,0,0,19		/* extract address of pte page */
604	b	1b
605
606#ifndef CONFIG_ALTIVEC
607#define altivec_assist_exception	unknown_exception
608#endif
609
610#ifndef CONFIG_TAU_INT
611#define TAUException	unknown_async_exception
612#endif
613
614	EXCEPTION(0x1300, Trap_13, instruction_breakpoint_exception)
615	EXCEPTION(0x1400, SMI, SMIException)
616	EXCEPTION(0x1500, Trap_15, unknown_exception)
617	EXCEPTION(0x1600, Trap_16, altivec_assist_exception)
618	EXCEPTION(0x1700, Trap_17, TAUException)
619	EXCEPTION(0x1800, Trap_18, unknown_exception)
620	EXCEPTION(0x1900, Trap_19, unknown_exception)
621	EXCEPTION(0x1a00, Trap_1a, unknown_exception)
622	EXCEPTION(0x1b00, Trap_1b, unknown_exception)
623	EXCEPTION(0x1c00, Trap_1c, unknown_exception)
624	EXCEPTION(0x1d00, Trap_1d, unknown_exception)
625	EXCEPTION(0x1e00, Trap_1e, unknown_exception)
626	EXCEPTION(0x1f00, Trap_1f, unknown_exception)
627	EXCEPTION(0x2000, RunMode, RunModeException)
628	EXCEPTION(0x2100, Trap_21, unknown_exception)
629	EXCEPTION(0x2200, Trap_22, unknown_exception)
630	EXCEPTION(0x2300, Trap_23, unknown_exception)
631	EXCEPTION(0x2400, Trap_24, unknown_exception)
632	EXCEPTION(0x2500, Trap_25, unknown_exception)
633	EXCEPTION(0x2600, Trap_26, unknown_exception)
634	EXCEPTION(0x2700, Trap_27, unknown_exception)
635	EXCEPTION(0x2800, Trap_28, unknown_exception)
636	EXCEPTION(0x2900, Trap_29, unknown_exception)
637	EXCEPTION(0x2a00, Trap_2a, unknown_exception)
638	EXCEPTION(0x2b00, Trap_2b, unknown_exception)
639	EXCEPTION(0x2c00, Trap_2c, unknown_exception)
640	EXCEPTION(0x2d00, Trap_2d, unknown_exception)
641	EXCEPTION(0x2e00, Trap_2e, unknown_exception)
642	EXCEPTION(0x2f00, Trap_2f, unknown_exception)
643
644	__HEAD
645	. = 0x3000
646
647#ifdef CONFIG_PPC_BOOK3S_604
648.macro save_regs_thread		thread
649	stw	r0, THR0(\thread)
650	stw	r3, THR3(\thread)
651	stw	r4, THR4(\thread)
652	stw	r5, THR5(\thread)
653	stw	r6, THR6(\thread)
654	stw	r8, THR8(\thread)
655	stw	r9, THR9(\thread)
656	mflr	r0
657	stw	r0, THLR(\thread)
658	mfctr	r0
659	stw	r0, THCTR(\thread)
660.endm
661
662.macro restore_regs_thread	thread
663	lwz	r0, THLR(\thread)
664	mtlr	r0
665	lwz	r0, THCTR(\thread)
666	mtctr	r0
667	lwz	r0, THR0(\thread)
668	lwz	r3, THR3(\thread)
669	lwz	r4, THR4(\thread)
670	lwz	r5, THR5(\thread)
671	lwz	r6, THR6(\thread)
672	lwz	r8, THR8(\thread)
673	lwz	r9, THR9(\thread)
674.endm
675
676hash_page_dsi:
677	save_regs_thread	r10
678	mfdsisr	r3
679	mfdar	r4
680	mfsrr0	r5
681	mfsrr1	r9
682	rlwinm	r3, r3, 32 - 15, _PAGE_WRITE	/* DSISR_STORE -> _PAGE_WRITE */
683	ori	r3, r3, _PAGE_PRESENT | _PAGE_READ
684	bl	hash_page
685	mfspr	r10, SPRN_SPRG_THREAD
686	restore_regs_thread r10
687	b	.Lhash_page_dsi_cont
688
689hash_page_isi:
690	mr	r11, r10
691	mfspr	r10, SPRN_SPRG_THREAD
692	save_regs_thread	r10
693	li	r3, _PAGE_PRESENT | _PAGE_EXEC
694	lwz	r4, SRR0(r10)
695	lwz	r9, SRR1(r10)
696	bl	hash_page
697	mfspr	r10, SPRN_SPRG_THREAD
698	restore_regs_thread r10
699	mr	r10, r11
700	b	.Lhash_page_isi_cont
701
702	.globl fast_hash_page_return
703fast_hash_page_return:
704	andis.	r10, r9, SRR1_ISI_NOPT@h	/* Set on ISI, cleared on DSI */
705	mfspr	r10, SPRN_SPRG_THREAD
706	restore_regs_thread r10
707	bne	1f
708
709	/* DSI */
710	mtcr	r11
711	lwz	r11, THR11(r10)
712	mfspr	r10, SPRN_SPRG_SCRATCH2
713	rfi
714
7151:	/* ISI */
716	mtcr	r11
717	mfspr	r11, SPRN_SPRG_SCRATCH1
718	mfspr	r10, SPRN_SPRG_SCRATCH0
719	rfi
720#endif /* CONFIG_PPC_BOOK3S_604 */
721
722#ifdef CONFIG_VMAP_STACK
723	vmap_stack_overflow_exception
724#endif
725
726	__HEAD
727AltiVecUnavailable:
728	EXCEPTION_PROLOG 0xf20 AltiVecUnavailable
729#ifdef CONFIG_ALTIVEC
730	beq	1f
731	bl	load_up_altivec		/* if from user, just load it up */
732	b	fast_exception_return
733#endif /* CONFIG_ALTIVEC */
7341:	prepare_transfer_to_handler
735	bl	altivec_unavailable_exception
736	b	interrupt_return
737
738	__HEAD
739PerformanceMonitor:
740	EXCEPTION_PROLOG 0xf00 PerformanceMonitor
741	prepare_transfer_to_handler
742	bl	performance_monitor_exception
743	b	interrupt_return
744
745
746	__HEAD
747/*
748 * This code is jumped to from the startup code to copy
749 * the kernel image to physical address PHYSICAL_START.
750 */
751relocate_kernel:
752	lis	r3,PHYSICAL_START@h	/* Destination base address */
753	li	r6,0			/* Destination offset */
754	li	r5,0x4000		/* # bytes of memory to copy */
755	bl	copy_and_flush		/* copy the first 0x4000 bytes */
756	addi	r0,r3,4f@l		/* jump to the address of 4f */
757	mtctr	r0			/* in copy and do the rest. */
758	bctr				/* jump to the copy */
7594:	lis	r5,_end-KERNELBASE@h
760	ori	r5,r5,_end-KERNELBASE@l
761	bl	copy_and_flush		/* copy the rest */
762	b	turn_on_mmu
763
764/*
765 * Copy routine used to copy the kernel to start at physical address 0
766 * and flush and invalidate the caches as needed.
767 * r3 = dest addr, r4 = source addr, r5 = copy limit, r6 = start offset
768 * on exit, r3, r4, r5 are unchanged, r6 is updated to be >= r5.
769 */
770_GLOBAL(copy_and_flush)
771	addi	r5,r5,-4
772	addi	r6,r6,-4
7734:	li	r0,L1_CACHE_BYTES/4
774	mtctr	r0
7753:	addi	r6,r6,4			/* copy a cache line */
776	lwzx	r0,r6,r4
777	stwx	r0,r6,r3
778	bdnz	3b
779	dcbst	r6,r3			/* write it to memory */
780	sync
781	icbi	r6,r3			/* flush the icache line */
782	cmplw	0,r6,r5
783	blt	4b
784	sync				/* additional sync needed on g4 */
785	isync
786	addi	r5,r5,4
787	addi	r6,r6,4
788	blr
789
790#ifdef CONFIG_SMP
791	.globl __secondary_start_mpc86xx
792__secondary_start_mpc86xx:
793	mfspr	r3, SPRN_PIR
794	stw	r3, __secondary_hold_acknowledge@l(0)
795	mr	r24, r3			/* cpu # */
796	b	__secondary_start
797
798	.globl	__secondary_start_pmac_0
799__secondary_start_pmac_0:
800	/* NB the entries for cpus 0, 1, 2 must each occupy 8 bytes. */
801	li	r24,0
802	b	1f
803	li	r24,1
804	b	1f
805	li	r24,2
806	b	1f
807	li	r24,3
8081:
809	/* on powersurge, we come in here with IR=0 and DR=1, and DBAT 0
810	   set to map the 0xf0000000 - 0xffffffff region */
811	mfmsr	r0
812	rlwinm	r0,r0,0,28,26		/* clear DR (0x10) */
813	mtmsr	r0
814	isync
815
816	.globl	__secondary_start
817__secondary_start:
818	/* Copy some CPU settings from CPU 0 */
819	bl	__restore_cpu_setup
820
821	lis	r3,-KERNELBASE@h
822	mr	r4,r24
823	bl	call_setup_cpu		/* Call setup_cpu for this CPU */
824	lis	r3,-KERNELBASE@h
825	bl	init_idle_6xx
826
827	/* get current's stack and current */
828	lis	r2,secondary_current@ha
829	tophys(r2,r2)
830	lwz	r2,secondary_current@l(r2)
831	tophys(r1,r2)
832	lwz	r1,TASK_STACK(r1)
833
834	/* stack */
835	addi	r1,r1,THREAD_SIZE-STACK_FRAME_MIN_SIZE
836	li	r0,0
837	tophys(r3,r1)
838	stw	r0,0(r3)
839
840	/* load up the MMU */
841	bl	load_segment_registers
842	bl	load_up_mmu
843
844	/* ptr to phys current thread */
845	tophys(r4,r2)
846	addi	r4,r4,THREAD	/* phys address of our thread_struct */
847	mtspr	SPRN_SPRG_THREAD,r4
848BEGIN_MMU_FTR_SECTION
849	lis	r4, (swapper_pg_dir - PAGE_OFFSET)@h
850	ori	r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l
851	rlwinm	r4, r4, 4, 0xffff01ff
852	mtspr	SPRN_SDR1, r4
853END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
854
855	/* enable MMU and jump to start_secondary */
856	li	r4,MSR_KERNEL
857	lis	r3,start_secondary@h
858	ori	r3,r3,start_secondary@l
859	mtspr	SPRN_SRR0,r3
860	mtspr	SPRN_SRR1,r4
861	rfi
862#endif /* CONFIG_SMP */
863
864#ifdef CONFIG_KVM_BOOK3S_HANDLER
865#include "../kvm/book3s_rmhandlers.S"
866#endif
867
868/*
869 * Load stuff into the MMU.  Intended to be called with
870 * IR=0 and DR=0.
871 */
872SYM_FUNC_START_LOCAL(early_hash_table)
873	sync			/* Force all PTE updates to finish */
874	isync
875	tlbia			/* Clear all TLB entries */
876	sync			/* wait for tlbia/tlbie to finish */
877	TLBSYNC			/* ... on all CPUs */
878	/* Load the SDR1 register (hash table base & size) */
879	lis	r6, early_hash - PAGE_OFFSET@h
880	ori	r6, r6, 3	/* 256kB table */
881	mtspr	SPRN_SDR1, r6
882	blr
883SYM_FUNC_END(early_hash_table)
884
885SYM_FUNC_START_LOCAL(load_up_mmu)
886	sync			/* Force all PTE updates to finish */
887	isync
888	tlbia			/* Clear all TLB entries */
889	sync			/* wait for tlbia/tlbie to finish */
890	TLBSYNC			/* ... on all CPUs */
891BEGIN_MMU_FTR_SECTION
892	/* Load the SDR1 register (hash table base & size) */
893	lis	r6,_SDR1@ha
894	tophys(r6,r6)
895	lwz	r6,_SDR1@l(r6)
896	mtspr	SPRN_SDR1,r6
897END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
898
899/* Load the BAT registers with the values set up by MMU_init. */
900	lis	r3,BATS@ha
901	addi	r3,r3,BATS@l
902	tophys(r3,r3)
903	LOAD_BAT(0,r3,r4,r5)
904	LOAD_BAT(1,r3,r4,r5)
905	LOAD_BAT(2,r3,r4,r5)
906	LOAD_BAT(3,r3,r4,r5)
907BEGIN_MMU_FTR_SECTION
908	LOAD_BAT(4,r3,r4,r5)
909	LOAD_BAT(5,r3,r4,r5)
910	LOAD_BAT(6,r3,r4,r5)
911	LOAD_BAT(7,r3,r4,r5)
912END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
913	blr
914SYM_FUNC_END(load_up_mmu)
915
916_GLOBAL(load_segment_registers)
917	li	r0, NUM_USER_SEGMENTS /* load up user segment register values */
918	mtctr	r0		/* for context 0 */
919#ifdef CONFIG_PPC_KUEP
920	lis	r3, SR_NX@h	/* Kp = 0, Ks = 0, VSID = 0 */
921#else
922	li	r3, 0		/* Kp = 0, Ks = 0, VSID = 0 */
923#endif
924	li	r4, 0
9253:	mtsrin	r3, r4
926	addi	r3, r3, 0x111	/* increment VSID */
927	addis	r4, r4, 0x1000	/* address of next segment */
928	bdnz	3b
929	li	r0, 16 - NUM_USER_SEGMENTS /* load up kernel segment registers */
930	mtctr	r0			/* for context 0 */
931	rlwinm	r3, r3, 0, ~SR_NX	/* Nx = 0 */
932	rlwinm	r3, r3, 0, ~SR_KS	/* Ks = 0 */
933	oris	r3, r3, SR_KP@h		/* Kp = 1 */
9343:	mtsrin	r3, r4
935	addi	r3, r3, 0x111	/* increment VSID */
936	addis	r4, r4, 0x1000	/* address of next segment */
937	bdnz	3b
938	blr
939
940/*
941 * This is where the main kernel code starts.
942 */
943start_here:
944	/* ptr to current */
945	lis	r2,init_task@h
946	ori	r2,r2,init_task@l
947	/* Set up for using our exception vectors */
948	/* ptr to phys current thread */
949	tophys(r4,r2)
950	addi	r4,r4,THREAD	/* init task's THREAD */
951	mtspr	SPRN_SPRG_THREAD,r4
952BEGIN_MMU_FTR_SECTION
953	lis	r4, (swapper_pg_dir - PAGE_OFFSET)@h
954	ori	r4, r4, (swapper_pg_dir - PAGE_OFFSET)@l
955	rlwinm	r4, r4, 4, 0xffff01ff
956	mtspr	SPRN_SDR1, r4
957END_MMU_FTR_SECTION_IFCLR(MMU_FTR_HPTE_TABLE)
958
959	/* stack */
960	lis	r1,init_thread_union@ha
961	addi	r1,r1,init_thread_union@l
962	li	r0,0
963	stwu	r0,THREAD_SIZE-STACK_FRAME_MIN_SIZE(r1)
964/*
965 * Do early platform-specific initialization,
966 * and set up the MMU.
967 */
968#ifdef CONFIG_KASAN
969	bl	kasan_early_init
970#endif
971	li	r3,0
972	mr	r4,r31
973	bl	machine_init
974	bl	__save_cpu_setup
975	bl	MMU_init
976	bl	MMU_init_hw_patch
977
978/*
979 * Go back to running unmapped so we can load up new values
980 * for SDR1 (hash table pointer) and the segment registers
981 * and change to using our exception vectors.
982 */
983	lis	r4,2f@h
984	ori	r4,r4,2f@l
985	tophys(r4,r4)
986	li	r3,MSR_KERNEL & ~(MSR_IR|MSR_DR)
987
988	.align	4
989	mtspr	SPRN_SRR0,r4
990	mtspr	SPRN_SRR1,r3
991	rfi
992/* Load up the kernel context */
9932:	bl	load_up_mmu
994
995#ifdef CONFIG_BDI_SWITCH
996	/* Add helper information for the Abatron bdiGDB debugger.
997	 * We do this here because we know the mmu is disabled, and
998	 * will be enabled for real in just a few instructions.
999	 */
1000	lis	r5, abatron_pteptrs@h
1001	ori	r5, r5, abatron_pteptrs@l
1002	stw	r5, 0xf0(0)	/* This much match your Abatron config */
1003	lis	r6, swapper_pg_dir@h
1004	ori	r6, r6, swapper_pg_dir@l
1005	tophys(r5, r5)
1006	stw	r6, 0(r5)
1007#endif /* CONFIG_BDI_SWITCH */
1008
1009/* Now turn on the MMU for real! */
1010	li	r4,MSR_KERNEL
1011	lis	r3,start_kernel@h
1012	ori	r3,r3,start_kernel@l
1013	mtspr	SPRN_SRR0,r3
1014	mtspr	SPRN_SRR1,r4
1015	rfi
1016
1017/*
1018 * An undocumented "feature" of 604e requires that the v bit
1019 * be cleared before changing BAT values.
1020 *
1021 * Also, newer IBM firmware does not clear bat3 and 4 so
1022 * this makes sure it's done.
1023 *  -- Cort
1024 */
1025SYM_FUNC_START_LOCAL(clear_bats)
1026	li	r10,0
1027
1028	mtspr	SPRN_DBAT0U,r10
1029	mtspr	SPRN_DBAT0L,r10
1030	mtspr	SPRN_DBAT1U,r10
1031	mtspr	SPRN_DBAT1L,r10
1032	mtspr	SPRN_DBAT2U,r10
1033	mtspr	SPRN_DBAT2L,r10
1034	mtspr	SPRN_DBAT3U,r10
1035	mtspr	SPRN_DBAT3L,r10
1036	mtspr	SPRN_IBAT0U,r10
1037	mtspr	SPRN_IBAT0L,r10
1038	mtspr	SPRN_IBAT1U,r10
1039	mtspr	SPRN_IBAT1L,r10
1040	mtspr	SPRN_IBAT2U,r10
1041	mtspr	SPRN_IBAT2L,r10
1042	mtspr	SPRN_IBAT3U,r10
1043	mtspr	SPRN_IBAT3L,r10
1044BEGIN_MMU_FTR_SECTION
1045	/* Here's a tweak: at this point, CPU setup have
1046	 * not been called yet, so HIGH_BAT_EN may not be
1047	 * set in HID0 for the 745x processors. However, it
1048	 * seems that doesn't affect our ability to actually
1049	 * write to these SPRs.
1050	 */
1051	mtspr	SPRN_DBAT4U,r10
1052	mtspr	SPRN_DBAT4L,r10
1053	mtspr	SPRN_DBAT5U,r10
1054	mtspr	SPRN_DBAT5L,r10
1055	mtspr	SPRN_DBAT6U,r10
1056	mtspr	SPRN_DBAT6L,r10
1057	mtspr	SPRN_DBAT7U,r10
1058	mtspr	SPRN_DBAT7L,r10
1059	mtspr	SPRN_IBAT4U,r10
1060	mtspr	SPRN_IBAT4L,r10
1061	mtspr	SPRN_IBAT5U,r10
1062	mtspr	SPRN_IBAT5L,r10
1063	mtspr	SPRN_IBAT6U,r10
1064	mtspr	SPRN_IBAT6L,r10
1065	mtspr	SPRN_IBAT7U,r10
1066	mtspr	SPRN_IBAT7L,r10
1067END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
1068	blr
1069SYM_FUNC_END(clear_bats)
1070
1071_GLOBAL(update_bats)
1072	lis	r4, 1f@h
1073	ori	r4, r4, 1f@l
1074	tophys(r4, r4)
1075	mfmsr	r6
1076	mflr	r7
1077	li	r3, MSR_KERNEL & ~(MSR_IR | MSR_DR)
1078	rlwinm	r0, r6, 0, ~MSR_RI
1079	rlwinm	r0, r0, 0, ~MSR_EE
1080	mtmsr	r0
1081
1082	.align	4
1083	mtspr	SPRN_SRR0, r4
1084	mtspr	SPRN_SRR1, r3
1085	rfi
10861:	bl	clear_bats
1087	lis	r3, BATS@ha
1088	addi	r3, r3, BATS@l
1089	tophys(r3, r3)
1090	LOAD_BAT(0, r3, r4, r5)
1091	LOAD_BAT(1, r3, r4, r5)
1092	LOAD_BAT(2, r3, r4, r5)
1093	LOAD_BAT(3, r3, r4, r5)
1094BEGIN_MMU_FTR_SECTION
1095	LOAD_BAT(4, r3, r4, r5)
1096	LOAD_BAT(5, r3, r4, r5)
1097	LOAD_BAT(6, r3, r4, r5)
1098	LOAD_BAT(7, r3, r4, r5)
1099END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
1100	li	r3, MSR_KERNEL & ~(MSR_IR | MSR_DR | MSR_RI)
1101	mtmsr	r3
1102	mtspr	SPRN_SRR0, r7
1103	mtspr	SPRN_SRR1, r6
1104	rfi
1105
1106SYM_FUNC_START_LOCAL(flush_tlbs)
1107	lis	r10, 0x40
11081:	addic.	r10, r10, -0x1000
1109	tlbie	r10
1110	bgt	1b
1111	sync
1112	blr
1113SYM_FUNC_END(flush_tlbs)
1114
1115SYM_FUNC_START_LOCAL(mmu_off)
1116 	addi	r4, r3, __after_mmu_off - _start
1117	mfmsr	r3
1118	andi.	r0,r3,MSR_DR|MSR_IR		/* MMU enabled? */
1119	beqlr
1120	andc	r3,r3,r0
1121
1122	.align	4
1123	mtspr	SPRN_SRR0,r4
1124	mtspr	SPRN_SRR1,r3
1125	sync
1126	rfi
1127SYM_FUNC_END(mmu_off)
1128
1129/* We use one BAT to map up to 256M of RAM at _PAGE_OFFSET */
1130SYM_FUNC_START_LOCAL(initial_bats)
1131	lis	r11,PAGE_OFFSET@h
1132	tophys(r8,r11)
1133#ifdef CONFIG_SMP
1134	ori	r8,r8,0x12		/* R/W access, M=1 */
1135#else
1136	ori	r8,r8,2			/* R/W access */
1137#endif /* CONFIG_SMP */
1138	ori	r11,r11,BL_256M<<2|0x2	/* set up BAT registers for 604 */
1139
1140	mtspr	SPRN_DBAT0L,r8		/* N.B. 6xx have valid */
1141	mtspr	SPRN_DBAT0U,r11		/* bit in upper BAT register */
1142	mtspr	SPRN_IBAT0L,r8
1143	mtspr	SPRN_IBAT0U,r11
1144	isync
1145	blr
1146SYM_FUNC_END(initial_bats)
1147
1148#ifdef CONFIG_BOOTX_TEXT
1149SYM_FUNC_START_LOCAL(setup_disp_bat)
1150	/*
1151	 * setup the display bat prepared for us in prom.c
1152	 */
1153	mflr	r8
1154	bl	reloc_offset
1155	mtlr	r8
1156	addis	r8,r3,disp_BAT@ha
1157	addi	r8,r8,disp_BAT@l
1158	cmpwi	cr0,r8,0
1159	beqlr
1160	lwz	r11,0(r8)
1161	lwz	r8,4(r8)
1162	mtspr	SPRN_DBAT3L,r8
1163	mtspr	SPRN_DBAT3U,r11
1164	blr
1165SYM_FUNC_END(setup_disp_bat)
1166#endif /* CONFIG_BOOTX_TEXT */
1167
1168#ifdef CONFIG_PPC_EARLY_DEBUG_CPM
1169SYM_FUNC_START_LOCAL(setup_cpm_bat)
1170	lis	r8, 0xf000
1171	ori	r8, r8,	0x002a
1172	mtspr	SPRN_DBAT1L, r8
1173
1174	lis	r11, 0xf000
1175	ori	r11, r11, (BL_1M << 2) | 2
1176	mtspr	SPRN_DBAT1U, r11
1177
1178	blr
1179SYM_FUNC_END(setup_cpm_bat)
1180#endif
1181
1182#ifdef CONFIG_PPC_EARLY_DEBUG_USBGECKO
1183SYM_FUNC_START_LOCAL(setup_usbgecko_bat)
1184	/* prepare a BAT for early io */
1185#if defined(CONFIG_GAMECUBE)
1186	lis	r8, 0x0c00
1187#elif defined(CONFIG_WII)
1188	lis	r8, 0x0d00
1189#else
1190#error Invalid platform for USB Gecko based early debugging.
1191#endif
1192	/*
1193	 * The virtual address used must match the virtual address
1194	 * associated to the fixmap entry FIX_EARLY_DEBUG_BASE.
1195	 */
1196	lis	r11, 0xfffe	/* top 128K */
1197	ori	r8, r8, 0x002a	/* uncached, guarded ,rw */
1198	ori	r11, r11, 0x2	/* 128K, Vs=1, Vp=0 */
1199	mtspr	SPRN_DBAT1L, r8
1200	mtspr	SPRN_DBAT1U, r11
1201	blr
1202SYM_FUNC_END(setup_usbgecko_bat)
1203#endif
1204
1205	.data
1206