xref: /openbmc/linux/arch/arm/kernel/head.S (revision d2999e1b)
1/*
2 *  linux/arch/arm/kernel/head.S
3 *
4 *  Copyright (C) 1994-2002 Russell King
5 *  Copyright (c) 2003 ARM Limited
6 *  All Rights Reserved
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 *  Kernel startup code for all 32-bit CPUs
13 */
14#include <linux/linkage.h>
15#include <linux/init.h>
16
17#include <asm/assembler.h>
18#include <asm/cp15.h>
19#include <asm/domain.h>
20#include <asm/ptrace.h>
21#include <asm/asm-offsets.h>
22#include <asm/memory.h>
23#include <asm/thread_info.h>
24#include <asm/pgtable.h>
25
26#if defined(CONFIG_DEBUG_LL) && !defined(CONFIG_DEBUG_SEMIHOSTING)
27#include CONFIG_DEBUG_LL_INCLUDE
28#endif
29
30/*
31 * swapper_pg_dir is the virtual address of the initial page table.
32 * We place the page tables 16K below KERNEL_RAM_VADDR.  Therefore, we must
33 * make sure that KERNEL_RAM_VADDR is correctly set.  Currently, we expect
34 * the least significant 16 bits to be 0x8000, but we could probably
35 * relax this restriction to KERNEL_RAM_VADDR >= PAGE_OFFSET + 0x4000.
36 */
37#define KERNEL_RAM_VADDR	(PAGE_OFFSET + TEXT_OFFSET)
38#if (KERNEL_RAM_VADDR & 0xffff) != 0x8000
39#error KERNEL_RAM_VADDR must start at 0xXXXX8000
40#endif
41
42#ifdef CONFIG_ARM_LPAE
43	/* LPAE requires an additional page for the PGD */
44#define PG_DIR_SIZE	0x5000
45#define PMD_ORDER	3
46#else
47#define PG_DIR_SIZE	0x4000
48#define PMD_ORDER	2
49#endif
50
51	.globl	swapper_pg_dir
52	.equ	swapper_pg_dir, KERNEL_RAM_VADDR - PG_DIR_SIZE
53
54	.macro	pgtbl, rd, phys
55	add	\rd, \phys, #TEXT_OFFSET
56	sub	\rd, \rd, #PG_DIR_SIZE
57	.endm
58
59/*
60 * Kernel startup entry point.
61 * ---------------------------
62 *
63 * This is normally called from the decompressor code.  The requirements
64 * are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
65 * r1 = machine nr, r2 = atags or dtb pointer.
66 *
67 * This code is mostly position independent, so if you link the kernel at
68 * 0xc0008000, you call this at __pa(0xc0008000).
69 *
70 * See linux/arch/arm/tools/mach-types for the complete list of machine
71 * numbers for r1.
72 *
73 * We're trying to keep crap to a minimum; DO NOT add any machine specific
74 * crap here - that's what the boot loader (or in extreme, well justified
75 * circumstances, zImage) is for.
76 */
77	.arm
78
79	__HEAD
80ENTRY(stext)
81 ARM_BE8(setend	be )			@ ensure we are in BE8 mode
82
83 THUMB(	adr	r9, BSYM(1f)	)	@ Kernel is always entered in ARM.
84 THUMB(	bx	r9		)	@ If this is a Thumb-2 kernel,
85 THUMB(	.thumb			)	@ switch to Thumb now.
86 THUMB(1:			)
87
88#ifdef CONFIG_ARM_VIRT_EXT
89	bl	__hyp_stub_install
90#endif
91	@ ensure svc mode and all interrupts masked
92	safe_svcmode_maskall r9
93
94	mrc	p15, 0, r9, c0, c0		@ get processor id
95	bl	__lookup_processor_type		@ r5=procinfo r9=cpuid
96	movs	r10, r5				@ invalid processor (r5=0)?
97 THUMB( it	eq )		@ force fixup-able long branch encoding
98	beq	__error_p			@ yes, error 'p'
99
100#ifdef CONFIG_ARM_LPAE
101	mrc	p15, 0, r3, c0, c1, 4		@ read ID_MMFR0
102	and	r3, r3, #0xf			@ extract VMSA support
103	cmp	r3, #5				@ long-descriptor translation table format?
104 THUMB( it	lo )				@ force fixup-able long branch encoding
105	blo	__error_lpae			@ only classic page table format
106#endif
107
108#ifndef CONFIG_XIP_KERNEL
109	adr	r3, 2f
110	ldmia	r3, {r4, r8}
111	sub	r4, r3, r4			@ (PHYS_OFFSET - PAGE_OFFSET)
112	add	r8, r8, r4			@ PHYS_OFFSET
113#else
114	ldr	r8, =PLAT_PHYS_OFFSET		@ always constant in this case
115#endif
116
117	/*
118	 * r1 = machine no, r2 = atags or dtb,
119	 * r8 = phys_offset, r9 = cpuid, r10 = procinfo
120	 */
121	bl	__vet_atags
122#ifdef CONFIG_SMP_ON_UP
123	bl	__fixup_smp
124#endif
125#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
126	bl	__fixup_pv_table
127#endif
128	bl	__create_page_tables
129
130	/*
131	 * The following calls CPU specific code in a position independent
132	 * manner.  See arch/arm/mm/proc-*.S for details.  r10 = base of
133	 * xxx_proc_info structure selected by __lookup_processor_type
134	 * above.  On return, the CPU will be ready for the MMU to be
135	 * turned on, and r0 will hold the CPU control register value.
136	 */
137	ldr	r13, =__mmap_switched		@ address to jump to after
138						@ mmu has been enabled
139	adr	lr, BSYM(1f)			@ return (PIC) address
140	mov	r8, r4				@ set TTBR1 to swapper_pg_dir
141 ARM(	add	pc, r10, #PROCINFO_INITFUNC	)
142 THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)
143 THUMB(	mov	pc, r12				)
1441:	b	__enable_mmu
145ENDPROC(stext)
146	.ltorg
147#ifndef CONFIG_XIP_KERNEL
1482:	.long	.
149	.long	PAGE_OFFSET
150#endif
151
152/*
153 * Setup the initial page tables.  We only setup the barest
154 * amount which are required to get the kernel running, which
155 * generally means mapping in the kernel code.
156 *
157 * r8 = phys_offset, r9 = cpuid, r10 = procinfo
158 *
159 * Returns:
160 *  r0, r3, r5-r7 corrupted
161 *  r4 = page table (see ARCH_PGD_SHIFT in asm/memory.h)
162 */
163__create_page_tables:
164	pgtbl	r4, r8				@ page table address
165
166	/*
167	 * Clear the swapper page table
168	 */
169	mov	r0, r4
170	mov	r3, #0
171	add	r6, r0, #PG_DIR_SIZE
1721:	str	r3, [r0], #4
173	str	r3, [r0], #4
174	str	r3, [r0], #4
175	str	r3, [r0], #4
176	teq	r0, r6
177	bne	1b
178
179#ifdef CONFIG_ARM_LPAE
180	/*
181	 * Build the PGD table (first level) to point to the PMD table. A PGD
182	 * entry is 64-bit wide.
183	 */
184	mov	r0, r4
185	add	r3, r4, #0x1000			@ first PMD table address
186	orr	r3, r3, #3			@ PGD block type
187	mov	r6, #4				@ PTRS_PER_PGD
188	mov	r7, #1 << (55 - 32)		@ L_PGD_SWAPPER
1891:
190#ifdef CONFIG_CPU_ENDIAN_BE8
191	str	r7, [r0], #4			@ set top PGD entry bits
192	str	r3, [r0], #4			@ set bottom PGD entry bits
193#else
194	str	r3, [r0], #4			@ set bottom PGD entry bits
195	str	r7, [r0], #4			@ set top PGD entry bits
196#endif
197	add	r3, r3, #0x1000			@ next PMD table
198	subs	r6, r6, #1
199	bne	1b
200
201	add	r4, r4, #0x1000			@ point to the PMD tables
202#ifdef CONFIG_CPU_ENDIAN_BE8
203	add	r4, r4, #4			@ we only write the bottom word
204#endif
205#endif
206
207	ldr	r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags
208
209	/*
210	 * Create identity mapping to cater for __enable_mmu.
211	 * This identity mapping will be removed by paging_init().
212	 */
213	adr	r0, __turn_mmu_on_loc
214	ldmia	r0, {r3, r5, r6}
215	sub	r0, r0, r3			@ virt->phys offset
216	add	r5, r5, r0			@ phys __turn_mmu_on
217	add	r6, r6, r0			@ phys __turn_mmu_on_end
218	mov	r5, r5, lsr #SECTION_SHIFT
219	mov	r6, r6, lsr #SECTION_SHIFT
220
2211:	orr	r3, r7, r5, lsl #SECTION_SHIFT	@ flags + kernel base
222	str	r3, [r4, r5, lsl #PMD_ORDER]	@ identity mapping
223	cmp	r5, r6
224	addlo	r5, r5, #1			@ next section
225	blo	1b
226
227	/*
228	 * Map our RAM from the start to the end of the kernel .bss section.
229	 */
230	add	r0, r4, #PAGE_OFFSET >> (SECTION_SHIFT - PMD_ORDER)
231	ldr	r6, =(_end - 1)
232	orr	r3, r8, r7
233	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
2341:	str	r3, [r0], #1 << PMD_ORDER
235	add	r3, r3, #1 << SECTION_SHIFT
236	cmp	r0, r6
237	bls	1b
238
239#ifdef CONFIG_XIP_KERNEL
240	/*
241	 * Map the kernel image separately as it is not located in RAM.
242	 */
243#define XIP_START XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
244	mov	r3, pc
245	mov	r3, r3, lsr #SECTION_SHIFT
246	orr	r3, r7, r3, lsl #SECTION_SHIFT
247	add	r0, r4,  #(XIP_START & 0xff000000) >> (SECTION_SHIFT - PMD_ORDER)
248	str	r3, [r0, #((XIP_START & 0x00f00000) >> SECTION_SHIFT) << PMD_ORDER]!
249	ldr	r6, =(_edata_loc - 1)
250	add	r0, r0, #1 << PMD_ORDER
251	add	r6, r4, r6, lsr #(SECTION_SHIFT - PMD_ORDER)
2521:	cmp	r0, r6
253	add	r3, r3, #1 << SECTION_SHIFT
254	strls	r3, [r0], #1 << PMD_ORDER
255	bls	1b
256#endif
257
258	/*
259	 * Then map boot params address in r2 if specified.
260	 * We map 2 sections in case the ATAGs/DTB crosses a section boundary.
261	 */
262	mov	r0, r2, lsr #SECTION_SHIFT
263	movs	r0, r0, lsl #SECTION_SHIFT
264	subne	r3, r0, r8
265	addne	r3, r3, #PAGE_OFFSET
266	addne	r3, r4, r3, lsr #(SECTION_SHIFT - PMD_ORDER)
267	orrne	r6, r7, r0
268	strne	r6, [r3], #1 << PMD_ORDER
269	addne	r6, r6, #1 << SECTION_SHIFT
270	strne	r6, [r3]
271
272#if defined(CONFIG_ARM_LPAE) && defined(CONFIG_CPU_ENDIAN_BE8)
273	sub	r4, r4, #4			@ Fixup page table pointer
274						@ for 64-bit descriptors
275#endif
276
277#ifdef CONFIG_DEBUG_LL
278#if !defined(CONFIG_DEBUG_ICEDCC) && !defined(CONFIG_DEBUG_SEMIHOSTING)
279	/*
280	 * Map in IO space for serial debugging.
281	 * This allows debug messages to be output
282	 * via a serial console before paging_init.
283	 */
284	addruart r7, r3, r0
285
286	mov	r3, r3, lsr #SECTION_SHIFT
287	mov	r3, r3, lsl #PMD_ORDER
288
289	add	r0, r4, r3
290	mov	r3, r7, lsr #SECTION_SHIFT
291	ldr	r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
292	orr	r3, r7, r3, lsl #SECTION_SHIFT
293#ifdef CONFIG_ARM_LPAE
294	mov	r7, #1 << (54 - 32)		@ XN
295#ifdef CONFIG_CPU_ENDIAN_BE8
296	str	r7, [r0], #4
297	str	r3, [r0], #4
298#else
299	str	r3, [r0], #4
300	str	r7, [r0], #4
301#endif
302#else
303	orr	r3, r3, #PMD_SECT_XN
304	str	r3, [r0], #4
305#endif
306
307#else /* CONFIG_DEBUG_ICEDCC || CONFIG_DEBUG_SEMIHOSTING */
308	/* we don't need any serial debugging mappings */
309	ldr	r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
310#endif
311
312#if defined(CONFIG_ARCH_NETWINDER) || defined(CONFIG_ARCH_CATS)
313	/*
314	 * If we're using the NetWinder or CATS, we also need to map
315	 * in the 16550-type serial port for the debug messages
316	 */
317	add	r0, r4, #0xff000000 >> (SECTION_SHIFT - PMD_ORDER)
318	orr	r3, r7, #0x7c000000
319	str	r3, [r0]
320#endif
321#ifdef CONFIG_ARCH_RPC
322	/*
323	 * Map in screen at 0x02000000 & SCREEN2_BASE
324	 * Similar reasons here - for debug.  This is
325	 * only for Acorn RiscPC architectures.
326	 */
327	add	r0, r4, #0x02000000 >> (SECTION_SHIFT - PMD_ORDER)
328	orr	r3, r7, #0x02000000
329	str	r3, [r0]
330	add	r0, r4, #0xd8000000 >> (SECTION_SHIFT - PMD_ORDER)
331	str	r3, [r0]
332#endif
333#endif
334#ifdef CONFIG_ARM_LPAE
335	sub	r4, r4, #0x1000		@ point to the PGD table
336	mov	r4, r4, lsr #ARCH_PGD_SHIFT
337#endif
338	mov	pc, lr
339ENDPROC(__create_page_tables)
340	.ltorg
341	.align
342__turn_mmu_on_loc:
343	.long	.
344	.long	__turn_mmu_on
345	.long	__turn_mmu_on_end
346
347#if defined(CONFIG_SMP)
348	.text
349ENTRY(secondary_startup)
350	/*
351	 * Common entry point for secondary CPUs.
352	 *
353	 * Ensure that we're in SVC mode, and IRQs are disabled.  Lookup
354	 * the processor type - there is no need to check the machine type
355	 * as it has already been validated by the primary processor.
356	 */
357
358 ARM_BE8(setend	be)				@ ensure we are in BE8 mode
359
360#ifdef CONFIG_ARM_VIRT_EXT
361	bl	__hyp_stub_install_secondary
362#endif
363	safe_svcmode_maskall r9
364
365	mrc	p15, 0, r9, c0, c0		@ get processor id
366	bl	__lookup_processor_type
367	movs	r10, r5				@ invalid processor?
368	moveq	r0, #'p'			@ yes, error 'p'
369 THUMB( it	eq )		@ force fixup-able long branch encoding
370	beq	__error_p
371
372	/*
373	 * Use the page tables supplied from  __cpu_up.
374	 */
375	adr	r4, __secondary_data
376	ldmia	r4, {r5, r7, r12}		@ address to jump to after
377	sub	lr, r4, r5			@ mmu has been enabled
378	ldr	r4, [r7, lr]			@ get secondary_data.pgdir
379	add	r7, r7, #4
380	ldr	r8, [r7, lr]			@ get secondary_data.swapper_pg_dir
381	adr	lr, BSYM(__enable_mmu)		@ return address
382	mov	r13, r12			@ __secondary_switched address
383 ARM(	add	pc, r10, #PROCINFO_INITFUNC	) @ initialise processor
384						  @ (return control reg)
385 THUMB(	add	r12, r10, #PROCINFO_INITFUNC	)
386 THUMB(	mov	pc, r12				)
387ENDPROC(secondary_startup)
388
389	/*
390	 * r6  = &secondary_data
391	 */
392ENTRY(__secondary_switched)
393	ldr	sp, [r7, #4]			@ get secondary_data.stack
394	mov	fp, #0
395	b	secondary_start_kernel
396ENDPROC(__secondary_switched)
397
398	.align
399
400	.type	__secondary_data, %object
401__secondary_data:
402	.long	.
403	.long	secondary_data
404	.long	__secondary_switched
405#endif /* defined(CONFIG_SMP) */
406
407
408
409/*
410 * Setup common bits before finally enabling the MMU.  Essentially
411 * this is just loading the page table pointer and domain access
412 * registers.
413 *
414 *  r0  = cp#15 control register
415 *  r1  = machine ID
416 *  r2  = atags or dtb pointer
417 *  r4  = page table (see ARCH_PGD_SHIFT in asm/memory.h)
418 *  r9  = processor ID
419 *  r13 = *virtual* address to jump to upon completion
420 */
421__enable_mmu:
422#if defined(CONFIG_ALIGNMENT_TRAP) && __LINUX_ARM_ARCH__ < 6
423	orr	r0, r0, #CR_A
424#else
425	bic	r0, r0, #CR_A
426#endif
427#ifdef CONFIG_CPU_DCACHE_DISABLE
428	bic	r0, r0, #CR_C
429#endif
430#ifdef CONFIG_CPU_BPREDICT_DISABLE
431	bic	r0, r0, #CR_Z
432#endif
433#ifdef CONFIG_CPU_ICACHE_DISABLE
434	bic	r0, r0, #CR_I
435#endif
436#ifndef CONFIG_ARM_LPAE
437	mov	r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
438		      domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
439		      domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \
440		      domain_val(DOMAIN_IO, DOMAIN_CLIENT))
441	mcr	p15, 0, r5, c3, c0, 0		@ load domain access register
442	mcr	p15, 0, r4, c2, c0, 0		@ load page table pointer
443#endif
444	b	__turn_mmu_on
445ENDPROC(__enable_mmu)
446
447/*
448 * Enable the MMU.  This completely changes the structure of the visible
449 * memory space.  You will not be able to trace execution through this.
450 * If you have an enquiry about this, *please* check the linux-arm-kernel
451 * mailing list archives BEFORE sending another post to the list.
452 *
453 *  r0  = cp#15 control register
454 *  r1  = machine ID
455 *  r2  = atags or dtb pointer
456 *  r9  = processor ID
457 *  r13 = *virtual* address to jump to upon completion
458 *
459 * other registers depend on the function called upon completion
460 */
461	.align	5
462	.pushsection	.idmap.text, "ax"
463ENTRY(__turn_mmu_on)
464	mov	r0, r0
465	instr_sync
466	mcr	p15, 0, r0, c1, c0, 0		@ write control reg
467	mrc	p15, 0, r3, c0, c0, 0		@ read id reg
468	instr_sync
469	mov	r3, r3
470	mov	r3, r13
471	mov	pc, r3
472__turn_mmu_on_end:
473ENDPROC(__turn_mmu_on)
474	.popsection
475
476
477#ifdef CONFIG_SMP_ON_UP
478	__HEAD
479__fixup_smp:
480	and	r3, r9, #0x000f0000	@ architecture version
481	teq	r3, #0x000f0000		@ CPU ID supported?
482	bne	__fixup_smp_on_up	@ no, assume UP
483
484	bic	r3, r9, #0x00ff0000
485	bic	r3, r3, #0x0000000f	@ mask 0xff00fff0
486	mov	r4, #0x41000000
487	orr	r4, r4, #0x0000b000
488	orr	r4, r4, #0x00000020	@ val 0x4100b020
489	teq	r3, r4			@ ARM 11MPCore?
490	moveq	pc, lr			@ yes, assume SMP
491
492	mrc	p15, 0, r0, c0, c0, 5	@ read MPIDR
493	and	r0, r0, #0xc0000000	@ multiprocessing extensions and
494	teq	r0, #0x80000000		@ not part of a uniprocessor system?
495	bne    __fixup_smp_on_up	@ no, assume UP
496
497	@ Core indicates it is SMP. Check for Aegis SOC where a single
498	@ Cortex-A9 CPU is present but SMP operations fault.
499	mov	r4, #0x41000000
500	orr	r4, r4, #0x0000c000
501	orr	r4, r4, #0x00000090
502	teq	r3, r4			@ Check for ARM Cortex-A9
503	movne	pc, lr			@ Not ARM Cortex-A9,
504
505	@ If a future SoC *does* use 0x0 as the PERIPH_BASE, then the
506	@ below address check will need to be #ifdef'd or equivalent
507	@ for the Aegis platform.
508	mrc	p15, 4, r0, c15, c0	@ get SCU base address
509	teq	r0, #0x0		@ '0' on actual UP A9 hardware
510	beq	__fixup_smp_on_up	@ So its an A9 UP
511	ldr	r0, [r0, #4]		@ read SCU Config
512ARM_BE8(rev	r0, r0)			@ byteswap if big endian
513	and	r0, r0, #0x3		@ number of CPUs
514	teq	r0, #0x0		@ is 1?
515	movne	pc, lr
516
517__fixup_smp_on_up:
518	adr	r0, 1f
519	ldmia	r0, {r3 - r5}
520	sub	r3, r0, r3
521	add	r4, r4, r3
522	add	r5, r5, r3
523	b	__do_fixup_smp_on_up
524ENDPROC(__fixup_smp)
525
526	.align
5271:	.word	.
528	.word	__smpalt_begin
529	.word	__smpalt_end
530
531	.pushsection .data
532	.globl	smp_on_up
533smp_on_up:
534	ALT_SMP(.long	1)
535	ALT_UP(.long	0)
536	.popsection
537#endif
538
539	.text
540__do_fixup_smp_on_up:
541	cmp	r4, r5
542	movhs	pc, lr
543	ldmia	r4!, {r0, r6}
544 ARM(	str	r6, [r0, r3]	)
545 THUMB(	add	r0, r0, r3	)
546#ifdef __ARMEB__
547 THUMB(	mov	r6, r6, ror #16	)	@ Convert word order for big-endian.
548#endif
549 THUMB(	strh	r6, [r0], #2	)	@ For Thumb-2, store as two halfwords
550 THUMB(	mov	r6, r6, lsr #16	)	@ to be robust against misaligned r3.
551 THUMB(	strh	r6, [r0]	)
552	b	__do_fixup_smp_on_up
553ENDPROC(__do_fixup_smp_on_up)
554
555ENTRY(fixup_smp)
556	stmfd	sp!, {r4 - r6, lr}
557	mov	r4, r0
558	add	r5, r0, r1
559	mov	r3, #0
560	bl	__do_fixup_smp_on_up
561	ldmfd	sp!, {r4 - r6, pc}
562ENDPROC(fixup_smp)
563
564#ifdef __ARMEB__
565#define LOW_OFFSET	0x4
566#define HIGH_OFFSET	0x0
567#else
568#define LOW_OFFSET	0x0
569#define HIGH_OFFSET	0x4
570#endif
571
572#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
573
574/* __fixup_pv_table - patch the stub instructions with the delta between
575 * PHYS_OFFSET and PAGE_OFFSET, which is assumed to be 16MiB aligned and
576 * can be expressed by an immediate shifter operand. The stub instruction
577 * has a form of '(add|sub) rd, rn, #imm'.
578 */
579	__HEAD
580__fixup_pv_table:
581	adr	r0, 1f
582	ldmia	r0, {r3-r7}
583	mvn	ip, #0
584	subs	r3, r0, r3	@ PHYS_OFFSET - PAGE_OFFSET
585	add	r4, r4, r3	@ adjust table start address
586	add	r5, r5, r3	@ adjust table end address
587	add	r6, r6, r3	@ adjust __pv_phys_pfn_offset address
588	add	r7, r7, r3	@ adjust __pv_offset address
589	mov	r0, r8, lsr #12	@ convert to PFN
590	str	r0, [r6]	@ save computed PHYS_OFFSET to __pv_phys_pfn_offset
591	strcc	ip, [r7, #HIGH_OFFSET]	@ save to __pv_offset high bits
592	mov	r6, r3, lsr #24	@ constant for add/sub instructions
593	teq	r3, r6, lsl #24 @ must be 16MiB aligned
594THUMB(	it	ne		@ cross section branch )
595	bne	__error
596	str	r3, [r7, #LOW_OFFSET]	@ save to __pv_offset low bits
597	b	__fixup_a_pv_table
598ENDPROC(__fixup_pv_table)
599
600	.align
6011:	.long	.
602	.long	__pv_table_begin
603	.long	__pv_table_end
6042:	.long	__pv_phys_pfn_offset
605	.long	__pv_offset
606
607	.text
608__fixup_a_pv_table:
609	adr	r0, 3f
610	ldr	r6, [r0]
611	add	r6, r6, r3
612	ldr	r0, [r6, #HIGH_OFFSET]	@ pv_offset high word
613	ldr	r6, [r6, #LOW_OFFSET]	@ pv_offset low word
614	mov	r6, r6, lsr #24
615	cmn	r0, #1
616#ifdef CONFIG_THUMB2_KERNEL
617	moveq	r0, #0x200000	@ set bit 21, mov to mvn instruction
618	lsls	r6, #24
619	beq	2f
620	clz	r7, r6
621	lsr	r6, #24
622	lsl	r6, r7
623	bic	r6, #0x0080
624	lsrs	r7, #1
625	orrcs	r6, #0x0080
626	orr	r6, r6, r7, lsl #12
627	orr	r6, #0x4000
628	b	2f
6291:	add     r7, r3
630	ldrh	ip, [r7, #2]
631ARM_BE8(rev16	ip, ip)
632	tst	ip, #0x4000
633	and	ip, #0x8f00
634	orrne	ip, r6	@ mask in offset bits 31-24
635	orreq	ip, r0	@ mask in offset bits 7-0
636ARM_BE8(rev16	ip, ip)
637	strh	ip, [r7, #2]
638	bne	2f
639	ldrh	ip, [r7]
640ARM_BE8(rev16	ip, ip)
641	bic	ip, #0x20
642	orr	ip, ip, r0, lsr #16
643ARM_BE8(rev16	ip, ip)
644	strh	ip, [r7]
6452:	cmp	r4, r5
646	ldrcc	r7, [r4], #4	@ use branch for delay slot
647	bcc	1b
648	bx	lr
649#else
650#ifdef CONFIG_CPU_ENDIAN_BE8
651	moveq	r0, #0x00004000	@ set bit 22, mov to mvn instruction
652#else
653	moveq	r0, #0x400000	@ set bit 22, mov to mvn instruction
654#endif
655	b	2f
6561:	ldr	ip, [r7, r3]
657#ifdef CONFIG_CPU_ENDIAN_BE8
658	@ in BE8, we load data in BE, but instructions still in LE
659	bic	ip, ip, #0xff000000
660	tst	ip, #0x000f0000	@ check the rotation field
661	orrne	ip, ip, r6, lsl #24 @ mask in offset bits 31-24
662	biceq	ip, ip, #0x00004000 @ clear bit 22
663	orreq	ip, ip, r0      @ mask in offset bits 7-0
664#else
665	bic	ip, ip, #0x000000ff
666	tst	ip, #0xf00	@ check the rotation field
667	orrne	ip, ip, r6	@ mask in offset bits 31-24
668	biceq	ip, ip, #0x400000	@ clear bit 22
669	orreq	ip, ip, r0	@ mask in offset bits 7-0
670#endif
671	str	ip, [r7, r3]
6722:	cmp	r4, r5
673	ldrcc	r7, [r4], #4	@ use branch for delay slot
674	bcc	1b
675	mov	pc, lr
676#endif
677ENDPROC(__fixup_a_pv_table)
678
679	.align
6803:	.long __pv_offset
681
682ENTRY(fixup_pv_table)
683	stmfd	sp!, {r4 - r7, lr}
684	mov	r3, #0			@ no offset
685	mov	r4, r0			@ r0 = table start
686	add	r5, r0, r1		@ r1 = table size
687	bl	__fixup_a_pv_table
688	ldmfd	sp!, {r4 - r7, pc}
689ENDPROC(fixup_pv_table)
690
691	.data
692	.globl	__pv_phys_pfn_offset
693	.type	__pv_phys_pfn_offset, %object
694__pv_phys_pfn_offset:
695	.word	0
696	.size	__pv_phys_pfn_offset, . -__pv_phys_pfn_offset
697
698	.globl	__pv_offset
699	.type	__pv_offset, %object
700__pv_offset:
701	.quad	0
702	.size	__pv_offset, . -__pv_offset
703#endif
704
705#include "head-common.S"
706