xref: /openbmc/linux/arch/arm/boot/compressed/head.S (revision ee89bd6b)
1/*
2 *  linux/arch/arm/boot/compressed/head.S
3 *
4 *  Copyright (C) 1996-2002 Russell King
5 *  Copyright (C) 2004 Hyok S. Choi (MPU support)
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/linkage.h>
12#include <asm/assembler.h>
13
14/*
15 * Debugging stuff
16 *
17 * Note that these macros must not contain any code which is not
18 * 100% relocatable.  Any attempt to do so will result in a crash.
19 * Please select one of the following when turning on debugging.
20 */
21#ifdef DEBUG
22
23#if defined(CONFIG_DEBUG_ICEDCC)
24
25#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
26		.macro	loadsp, rb, tmp
27		.endm
28		.macro	writeb, ch, rb
29		mcr	p14, 0, \ch, c0, c5, 0
30		.endm
31#elif defined(CONFIG_CPU_XSCALE)
32		.macro	loadsp, rb, tmp
33		.endm
34		.macro	writeb, ch, rb
35		mcr	p14, 0, \ch, c8, c0, 0
36		.endm
37#else
38		.macro	loadsp, rb, tmp
39		.endm
40		.macro	writeb, ch, rb
41		mcr	p14, 0, \ch, c1, c0, 0
42		.endm
43#endif
44
45#else
46
47#include CONFIG_DEBUG_LL_INCLUDE
48
49		.macro	writeb,	ch, rb
50		senduart \ch, \rb
51		.endm
52
53#if defined(CONFIG_ARCH_SA1100)
54		.macro	loadsp, rb, tmp
55		mov	\rb, #0x80000000	@ physical base address
56#ifdef CONFIG_DEBUG_LL_SER3
57		add	\rb, \rb, #0x00050000	@ Ser3
58#else
59		add	\rb, \rb, #0x00010000	@ Ser1
60#endif
61		.endm
62#elif defined(CONFIG_ARCH_S3C24XX)
63		.macro loadsp, rb, tmp
64		mov	\rb, #0x50000000
65		add	\rb, \rb, #0x4000 * CONFIG_S3C_LOWLEVEL_UART_PORT
66		.endm
67#else
68		.macro	loadsp,	rb, tmp
69		addruart \rb, \tmp
70		.endm
71#endif
72#endif
73#endif
74
75		.macro	kputc,val
76		mov	r0, \val
77		bl	putc
78		.endm
79
80		.macro	kphex,val,len
81		mov	r0, \val
82		mov	r1, #\len
83		bl	phex
84		.endm
85
86		.macro	debug_reloc_start
87#ifdef DEBUG
88		kputc	#'\n'
89		kphex	r6, 8		/* processor id */
90		kputc	#':'
91		kphex	r7, 8		/* architecture id */
92#ifdef CONFIG_CPU_CP15
93		kputc	#':'
94		mrc	p15, 0, r0, c1, c0
95		kphex	r0, 8		/* control reg */
96#endif
97		kputc	#'\n'
98		kphex	r5, 8		/* decompressed kernel start */
99		kputc	#'-'
100		kphex	r9, 8		/* decompressed kernel end  */
101		kputc	#'>'
102		kphex	r4, 8		/* kernel execution address */
103		kputc	#'\n'
104#endif
105		.endm
106
107		.macro	debug_reloc_end
108#ifdef DEBUG
109		kphex	r5, 8		/* end of kernel */
110		kputc	#'\n'
111		mov	r0, r4
112		bl	memdump		/* dump 256 bytes at start of kernel */
113#endif
114		.endm
115
116		.section ".start", #alloc, #execinstr
117/*
118 * sort out different calling conventions
119 */
120		.align
121		.arm				@ Always enter in ARM state
122start:
123		.type	start,#function
124		.rept	7
125		mov	r0, r0
126		.endr
127   ARM(		mov	r0, r0		)
128   ARM(		b	1f		)
129 THUMB(		adr	r12, BSYM(1f)	)
130 THUMB(		bx	r12		)
131
132		.word	0x016f2818		@ Magic numbers to help the loader
133		.word	start			@ absolute load/run zImage address
134		.word	_edata			@ zImage end address
135 THUMB(		.thumb			)
1361:
137		mrs	r9, cpsr
138#ifdef CONFIG_ARM_VIRT_EXT
139		bl	__hyp_stub_install	@ get into SVC mode, reversibly
140#endif
141		mov	r7, r1			@ save architecture ID
142		mov	r8, r2			@ save atags pointer
143
144#ifndef __ARM_ARCH_2__
145		/*
146		 * Booting from Angel - need to enter SVC mode and disable
147		 * FIQs/IRQs (numeric definitions from angel arm.h source).
148		 * We only do this if we were in user mode on entry.
149		 */
150		mrs	r2, cpsr		@ get current mode
151		tst	r2, #3			@ not user?
152		bne	not_angel
153		mov	r0, #0x17		@ angel_SWIreason_EnterSVC
154 ARM(		swi	0x123456	)	@ angel_SWI_ARM
155 THUMB(		svc	0xab		)	@ angel_SWI_THUMB
156not_angel:
157		safe_svcmode_maskall r0
158		msr	spsr_cxsf, r9		@ Save the CPU boot mode in
159						@ SPSR
160#else
161		teqp	pc, #0x0c000003		@ turn off interrupts
162#endif
163
164		/*
165		 * Note that some cache flushing and other stuff may
166		 * be needed here - is there an Angel SWI call for this?
167		 */
168
169		/*
170		 * some architecture specific code can be inserted
171		 * by the linker here, but it should preserve r7, r8, and r9.
172		 */
173
174		.text
175
176#ifdef CONFIG_AUTO_ZRELADDR
177		@ determine final kernel image address
178		mov	r4, pc
179		and	r4, r4, #0xf8000000
180		add	r4, r4, #TEXT_OFFSET
181#else
182		ldr	r4, =zreladdr
183#endif
184
185		bl	cache_on
186
187restart:	adr	r0, LC0
188		ldmia	r0, {r1, r2, r3, r6, r10, r11, r12}
189		ldr	sp, [r0, #28]
190
191		/*
192		 * We might be running at a different address.  We need
193		 * to fix up various pointers.
194		 */
195		sub	r0, r0, r1		@ calculate the delta offset
196		add	r6, r6, r0		@ _edata
197		add	r10, r10, r0		@ inflated kernel size location
198
199		/*
200		 * The kernel build system appends the size of the
201		 * decompressed kernel at the end of the compressed data
202		 * in little-endian form.
203		 */
204		ldrb	r9, [r10, #0]
205		ldrb	lr, [r10, #1]
206		orr	r9, r9, lr, lsl #8
207		ldrb	lr, [r10, #2]
208		ldrb	r10, [r10, #3]
209		orr	r9, r9, lr, lsl #16
210		orr	r9, r9, r10, lsl #24
211
212#ifndef CONFIG_ZBOOT_ROM
213		/* malloc space is above the relocated stack (64k max) */
214		add	sp, sp, r0
215		add	r10, sp, #0x10000
216#else
217		/*
218		 * With ZBOOT_ROM the bss/stack is non relocatable,
219		 * but someone could still run this code from RAM,
220		 * in which case our reference is _edata.
221		 */
222		mov	r10, r6
223#endif
224
225		mov	r5, #0			@ init dtb size to 0
226#ifdef CONFIG_ARM_APPENDED_DTB
227/*
228 *   r0  = delta
229 *   r2  = BSS start
230 *   r3  = BSS end
231 *   r4  = final kernel address
232 *   r5  = appended dtb size (still unknown)
233 *   r6  = _edata
234 *   r7  = architecture ID
235 *   r8  = atags/device tree pointer
236 *   r9  = size of decompressed image
237 *   r10 = end of this image, including  bss/stack/malloc space if non XIP
238 *   r11 = GOT start
239 *   r12 = GOT end
240 *   sp  = stack pointer
241 *
242 * if there are device trees (dtb) appended to zImage, advance r10 so that the
243 * dtb data will get relocated along with the kernel if necessary.
244 */
245
246		ldr	lr, [r6, #0]
247#ifndef __ARMEB__
248		ldr	r1, =0xedfe0dd0		@ sig is 0xd00dfeed big endian
249#else
250		ldr	r1, =0xd00dfeed
251#endif
252		cmp	lr, r1
253		bne	dtb_check_done		@ not found
254
255#ifdef CONFIG_ARM_ATAG_DTB_COMPAT
256		/*
257		 * OK... Let's do some funky business here.
258		 * If we do have a DTB appended to zImage, and we do have
259		 * an ATAG list around, we want the later to be translated
260		 * and folded into the former here.  To be on the safe side,
261		 * let's temporarily move  the stack away into the malloc
262		 * area.  No GOT fixup has occurred yet, but none of the
263		 * code we're about to call uses any global variable.
264		*/
265		add	sp, sp, #0x10000
266		stmfd	sp!, {r0-r3, ip, lr}
267		mov	r0, r8
268		mov	r1, r6
269		sub	r2, sp, r6
270		bl	atags_to_fdt
271
272		/*
273		 * If returned value is 1, there is no ATAG at the location
274		 * pointed by r8.  Try the typical 0x100 offset from start
275		 * of RAM and hope for the best.
276		 */
277		cmp	r0, #1
278		sub	r0, r4, #TEXT_OFFSET
279		add	r0, r0, #0x100
280		mov	r1, r6
281		sub	r2, sp, r6
282		bleq	atags_to_fdt
283
284		ldmfd	sp!, {r0-r3, ip, lr}
285		sub	sp, sp, #0x10000
286#endif
287
288		mov	r8, r6			@ use the appended device tree
289
290		/*
291		 * Make sure that the DTB doesn't end up in the final
292		 * kernel's .bss area. To do so, we adjust the decompressed
293		 * kernel size to compensate if that .bss size is larger
294		 * than the relocated code.
295		 */
296		ldr	r5, =_kernel_bss_size
297		adr	r1, wont_overwrite
298		sub	r1, r6, r1
299		subs	r1, r5, r1
300		addhi	r9, r9, r1
301
302		/* Get the dtb's size */
303		ldr	r5, [r6, #4]
304#ifndef __ARMEB__
305		/* convert r5 (dtb size) to little endian */
306		eor	r1, r5, r5, ror #16
307		bic	r1, r1, #0x00ff0000
308		mov	r5, r5, ror #8
309		eor	r5, r5, r1, lsr #8
310#endif
311
312		/* preserve 64-bit alignment */
313		add	r5, r5, #7
314		bic	r5, r5, #7
315
316		/* relocate some pointers past the appended dtb */
317		add	r6, r6, r5
318		add	r10, r10, r5
319		add	sp, sp, r5
320dtb_check_done:
321#endif
322
323/*
324 * Check to see if we will overwrite ourselves.
325 *   r4  = final kernel address
326 *   r9  = size of decompressed image
327 *   r10 = end of this image, including  bss/stack/malloc space if non XIP
328 * We basically want:
329 *   r4 - 16k page directory >= r10 -> OK
330 *   r4 + image length <= address of wont_overwrite -> OK
331 */
332		add	r10, r10, #16384
333		cmp	r4, r10
334		bhs	wont_overwrite
335		add	r10, r4, r9
336		adr	r9, wont_overwrite
337		cmp	r10, r9
338		bls	wont_overwrite
339
340/*
341 * Relocate ourselves past the end of the decompressed kernel.
342 *   r6  = _edata
343 *   r10 = end of the decompressed kernel
344 * Because we always copy ahead, we need to do it from the end and go
345 * backward in case the source and destination overlap.
346 */
347		/*
348		 * Bump to the next 256-byte boundary with the size of
349		 * the relocation code added. This avoids overwriting
350		 * ourself when the offset is small.
351		 */
352		add	r10, r10, #((reloc_code_end - restart + 256) & ~255)
353		bic	r10, r10, #255
354
355		/* Get start of code we want to copy and align it down. */
356		adr	r5, restart
357		bic	r5, r5, #31
358
359/* Relocate the hyp vector base if necessary */
360#ifdef CONFIG_ARM_VIRT_EXT
361		mrs	r0, spsr
362		and	r0, r0, #MODE_MASK
363		cmp	r0, #HYP_MODE
364		bne	1f
365
366		bl	__hyp_get_vectors
367		sub	r0, r0, r5
368		add	r0, r0, r10
369		bl	__hyp_set_vectors
3701:
371#endif
372
373		sub	r9, r6, r5		@ size to copy
374		add	r9, r9, #31		@ rounded up to a multiple
375		bic	r9, r9, #31		@ ... of 32 bytes
376		add	r6, r9, r5
377		add	r9, r9, r10
378
3791:		ldmdb	r6!, {r0 - r3, r10 - r12, lr}
380		cmp	r6, r5
381		stmdb	r9!, {r0 - r3, r10 - r12, lr}
382		bhi	1b
383
384		/* Preserve offset to relocated code. */
385		sub	r6, r9, r6
386
387#ifndef CONFIG_ZBOOT_ROM
388		/* cache_clean_flush may use the stack, so relocate it */
389		add	sp, sp, r6
390#endif
391
392		bl	cache_clean_flush
393
394		adr	r0, BSYM(restart)
395		add	r0, r0, r6
396		mov	pc, r0
397
398wont_overwrite:
399/*
400 * If delta is zero, we are running at the address we were linked at.
401 *   r0  = delta
402 *   r2  = BSS start
403 *   r3  = BSS end
404 *   r4  = kernel execution address
405 *   r5  = appended dtb size (0 if not present)
406 *   r7  = architecture ID
407 *   r8  = atags pointer
408 *   r11 = GOT start
409 *   r12 = GOT end
410 *   sp  = stack pointer
411 */
412		orrs	r1, r0, r5
413		beq	not_relocated
414
415		add	r11, r11, r0
416		add	r12, r12, r0
417
418#ifndef CONFIG_ZBOOT_ROM
419		/*
420		 * If we're running fully PIC === CONFIG_ZBOOT_ROM = n,
421		 * we need to fix up pointers into the BSS region.
422		 * Note that the stack pointer has already been fixed up.
423		 */
424		add	r2, r2, r0
425		add	r3, r3, r0
426
427		/*
428		 * Relocate all entries in the GOT table.
429		 * Bump bss entries to _edata + dtb size
430		 */
4311:		ldr	r1, [r11, #0]		@ relocate entries in the GOT
432		add	r1, r1, r0		@ This fixes up C references
433		cmp	r1, r2			@ if entry >= bss_start &&
434		cmphs	r3, r1			@       bss_end > entry
435		addhi	r1, r1, r5		@    entry += dtb size
436		str	r1, [r11], #4		@ next entry
437		cmp	r11, r12
438		blo	1b
439
440		/* bump our bss pointers too */
441		add	r2, r2, r5
442		add	r3, r3, r5
443
444#else
445
446		/*
447		 * Relocate entries in the GOT table.  We only relocate
448		 * the entries that are outside the (relocated) BSS region.
449		 */
4501:		ldr	r1, [r11, #0]		@ relocate entries in the GOT
451		cmp	r1, r2			@ entry < bss_start ||
452		cmphs	r3, r1			@ _end < entry
453		addlo	r1, r1, r0		@ table.  This fixes up the
454		str	r1, [r11], #4		@ C references.
455		cmp	r11, r12
456		blo	1b
457#endif
458
459not_relocated:	mov	r0, #0
4601:		str	r0, [r2], #4		@ clear bss
461		str	r0, [r2], #4
462		str	r0, [r2], #4
463		str	r0, [r2], #4
464		cmp	r2, r3
465		blo	1b
466
467/*
468 * The C runtime environment should now be setup sufficiently.
469 * Set up some pointers, and start decompressing.
470 *   r4  = kernel execution address
471 *   r7  = architecture ID
472 *   r8  = atags pointer
473 */
474		mov	r0, r4
475		mov	r1, sp			@ malloc space above stack
476		add	r2, sp, #0x10000	@ 64k max
477		mov	r3, r7
478		bl	decompress_kernel
479		bl	cache_clean_flush
480		bl	cache_off
481		mov	r1, r7			@ restore architecture number
482		mov	r2, r8			@ restore atags pointer
483
484#ifdef CONFIG_ARM_VIRT_EXT
485		mrs	r0, spsr		@ Get saved CPU boot mode
486		and	r0, r0, #MODE_MASK
487		cmp	r0, #HYP_MODE		@ if not booted in HYP mode...
488		bne	__enter_kernel		@ boot kernel directly
489
490		adr	r12, .L__hyp_reentry_vectors_offset
491		ldr	r0, [r12]
492		add	r0, r0, r12
493
494		bl	__hyp_set_vectors
495		__HVC(0)			@ otherwise bounce to hyp mode
496
497		b	.			@ should never be reached
498
499		.align	2
500.L__hyp_reentry_vectors_offset:	.long	__hyp_reentry_vectors - .
501#else
502		b	__enter_kernel
503#endif
504
505		.align	2
506		.type	LC0, #object
507LC0:		.word	LC0			@ r1
508		.word	__bss_start		@ r2
509		.word	_end			@ r3
510		.word	_edata			@ r6
511		.word	input_data_end - 4	@ r10 (inflated size location)
512		.word	_got_start		@ r11
513		.word	_got_end		@ ip
514		.word	.L_user_stack_end	@ sp
515		.size	LC0, . - LC0
516
517#ifdef CONFIG_ARCH_RPC
518		.globl	params
519params:		ldr	r0, =0x10000100		@ params_phys for RPC
520		mov	pc, lr
521		.ltorg
522		.align
523#endif
524
525/*
526 * Turn on the cache.  We need to setup some page tables so that we
527 * can have both the I and D caches on.
528 *
529 * We place the page tables 16k down from the kernel execution address,
530 * and we hope that nothing else is using it.  If we're using it, we
531 * will go pop!
532 *
533 * On entry,
534 *  r4 = kernel execution address
535 *  r7 = architecture number
536 *  r8 = atags pointer
537 * On exit,
538 *  r0, r1, r2, r3, r9, r10, r12 corrupted
539 * This routine must preserve:
540 *  r4, r7, r8
541 */
542		.align	5
543cache_on:	mov	r3, #8			@ cache_on function
544		b	call_cache_fn
545
546/*
547 * Initialize the highest priority protection region, PR7
548 * to cover all 32bit address and cacheable and bufferable.
549 */
550__armv4_mpu_cache_on:
551		mov	r0, #0x3f		@ 4G, the whole
552		mcr	p15, 0, r0, c6, c7, 0	@ PR7 Area Setting
553		mcr 	p15, 0, r0, c6, c7, 1
554
555		mov	r0, #0x80		@ PR7
556		mcr	p15, 0, r0, c2, c0, 0	@ D-cache on
557		mcr	p15, 0, r0, c2, c0, 1	@ I-cache on
558		mcr	p15, 0, r0, c3, c0, 0	@ write-buffer on
559
560		mov	r0, #0xc000
561		mcr	p15, 0, r0, c5, c0, 1	@ I-access permission
562		mcr	p15, 0, r0, c5, c0, 0	@ D-access permission
563
564		mov	r0, #0
565		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
566		mcr	p15, 0, r0, c7, c5, 0	@ flush(inval) I-Cache
567		mcr	p15, 0, r0, c7, c6, 0	@ flush(inval) D-Cache
568		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
569						@ ...I .... ..D. WC.M
570		orr	r0, r0, #0x002d		@ .... .... ..1. 11.1
571		orr	r0, r0, #0x1000		@ ...1 .... .... ....
572
573		mcr	p15, 0, r0, c1, c0, 0	@ write control reg
574
575		mov	r0, #0
576		mcr	p15, 0, r0, c7, c5, 0	@ flush(inval) I-Cache
577		mcr	p15, 0, r0, c7, c6, 0	@ flush(inval) D-Cache
578		mov	pc, lr
579
580__armv3_mpu_cache_on:
581		mov	r0, #0x3f		@ 4G, the whole
582		mcr	p15, 0, r0, c6, c7, 0	@ PR7 Area Setting
583
584		mov	r0, #0x80		@ PR7
585		mcr	p15, 0, r0, c2, c0, 0	@ cache on
586		mcr	p15, 0, r0, c3, c0, 0	@ write-buffer on
587
588		mov	r0, #0xc000
589		mcr	p15, 0, r0, c5, c0, 0	@ access permission
590
591		mov	r0, #0
592		mcr	p15, 0, r0, c7, c0, 0	@ invalidate whole cache v3
593		/*
594		 * ?? ARMv3 MMU does not allow reading the control register,
595		 * does this really work on ARMv3 MPU?
596		 */
597		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
598						@ .... .... .... WC.M
599		orr	r0, r0, #0x000d		@ .... .... .... 11.1
600		/* ?? this overwrites the value constructed above? */
601		mov	r0, #0
602		mcr	p15, 0, r0, c1, c0, 0	@ write control reg
603
604		/* ?? invalidate for the second time? */
605		mcr	p15, 0, r0, c7, c0, 0	@ invalidate whole cache v3
606		mov	pc, lr
607
608#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
609#define CB_BITS 0x08
610#else
611#define CB_BITS 0x0c
612#endif
613
614__setup_mmu:	sub	r3, r4, #16384		@ Page directory size
615		bic	r3, r3, #0xff		@ Align the pointer
616		bic	r3, r3, #0x3f00
617/*
618 * Initialise the page tables, turning on the cacheable and bufferable
619 * bits for the RAM area only.
620 */
621		mov	r0, r3
622		mov	r9, r0, lsr #18
623		mov	r9, r9, lsl #18		@ start of RAM
624		add	r10, r9, #0x10000000	@ a reasonable RAM size
625		mov	r1, #0x12		@ XN|U + section mapping
626		orr	r1, r1, #3 << 10	@ AP=11
627		add	r2, r3, #16384
6281:		cmp	r1, r9			@ if virt > start of RAM
629		cmphs	r10, r1			@   && end of RAM > virt
630		bic	r1, r1, #0x1c		@ clear XN|U + C + B
631		orrlo	r1, r1, #0x10		@ Set XN|U for non-RAM
632		orrhs	r1, r1, r6		@ set RAM section settings
633		str	r1, [r0], #4		@ 1:1 mapping
634		add	r1, r1, #1048576
635		teq	r0, r2
636		bne	1b
637/*
638 * If ever we are running from Flash, then we surely want the cache
639 * to be enabled also for our execution instance...  We map 2MB of it
640 * so there is no map overlap problem for up to 1 MB compressed kernel.
641 * If the execution is in RAM then we would only be duplicating the above.
642 */
643		orr	r1, r6, #0x04		@ ensure B is set for this
644		orr	r1, r1, #3 << 10
645		mov	r2, pc
646		mov	r2, r2, lsr #20
647		orr	r1, r1, r2, lsl #20
648		add	r0, r3, r2, lsl #2
649		str	r1, [r0], #4
650		add	r1, r1, #1048576
651		str	r1, [r0]
652		mov	pc, lr
653ENDPROC(__setup_mmu)
654
655@ Enable unaligned access on v6, to allow better code generation
656@ for the decompressor C code:
657__armv6_mmu_cache_on:
658		mrc	p15, 0, r0, c1, c0, 0	@ read SCTLR
659		bic	r0, r0, #2		@ A (no unaligned access fault)
660		orr	r0, r0, #1 << 22	@ U (v6 unaligned access model)
661		mcr	p15, 0, r0, c1, c0, 0	@ write SCTLR
662		b	__armv4_mmu_cache_on
663
664__arm926ejs_mmu_cache_on:
665#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
666		mov	r0, #4			@ put dcache in WT mode
667		mcr	p15, 7, r0, c15, c0, 0
668#endif
669
670__armv4_mmu_cache_on:
671		mov	r12, lr
672#ifdef CONFIG_MMU
673		mov	r6, #CB_BITS | 0x12	@ U
674		bl	__setup_mmu
675		mov	r0, #0
676		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
677		mcr	p15, 0, r0, c8, c7, 0	@ flush I,D TLBs
678		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
679		orr	r0, r0, #0x5000		@ I-cache enable, RR cache replacement
680		orr	r0, r0, #0x0030
681#ifdef CONFIG_CPU_ENDIAN_BE8
682		orr	r0, r0, #1 << 25	@ big-endian page tables
683#endif
684		bl	__common_mmu_cache_on
685		mov	r0, #0
686		mcr	p15, 0, r0, c8, c7, 0	@ flush I,D TLBs
687#endif
688		mov	pc, r12
689
690__armv7_mmu_cache_on:
691		mov	r12, lr
692#ifdef CONFIG_MMU
693		mrc	p15, 0, r11, c0, c1, 4	@ read ID_MMFR0
694		tst	r11, #0xf		@ VMSA
695		movne	r6, #CB_BITS | 0x02	@ !XN
696		blne	__setup_mmu
697		mov	r0, #0
698		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
699		tst	r11, #0xf		@ VMSA
700		mcrne	p15, 0, r0, c8, c7, 0	@ flush I,D TLBs
701#endif
702		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
703		bic	r0, r0, #1 << 28	@ clear SCTLR.TRE
704		orr	r0, r0, #0x5000		@ I-cache enable, RR cache replacement
705		orr	r0, r0, #0x003c		@ write buffer
706		bic	r0, r0, #2		@ A (no unaligned access fault)
707		orr	r0, r0, #1 << 22	@ U (v6 unaligned access model)
708						@ (needed for ARM1176)
709#ifdef CONFIG_MMU
710#ifdef CONFIG_CPU_ENDIAN_BE8
711		orr	r0, r0, #1 << 25	@ big-endian page tables
712#endif
713		mrcne   p15, 0, r6, c2, c0, 2   @ read ttb control reg
714		orrne	r0, r0, #1		@ MMU enabled
715		movne	r1, #0xfffffffd		@ domain 0 = client
716		bic     r6, r6, #1 << 31        @ 32-bit translation system
717		bic     r6, r6, #3 << 0         @ use only ttbr0
718		mcrne	p15, 0, r3, c2, c0, 0	@ load page table pointer
719		mcrne	p15, 0, r1, c3, c0, 0	@ load domain access control
720		mcrne   p15, 0, r6, c2, c0, 2   @ load ttb control
721#endif
722		mcr	p15, 0, r0, c7, c5, 4	@ ISB
723		mcr	p15, 0, r0, c1, c0, 0	@ load control register
724		mrc	p15, 0, r0, c1, c0, 0	@ and read it back
725		mov	r0, #0
726		mcr	p15, 0, r0, c7, c5, 4	@ ISB
727		mov	pc, r12
728
729__fa526_cache_on:
730		mov	r12, lr
731		mov	r6, #CB_BITS | 0x12	@ U
732		bl	__setup_mmu
733		mov	r0, #0
734		mcr	p15, 0, r0, c7, c7, 0	@ Invalidate whole cache
735		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
736		mcr	p15, 0, r0, c8, c7, 0	@ flush UTLB
737		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
738		orr	r0, r0, #0x1000		@ I-cache enable
739		bl	__common_mmu_cache_on
740		mov	r0, #0
741		mcr	p15, 0, r0, c8, c7, 0	@ flush UTLB
742		mov	pc, r12
743
744__common_mmu_cache_on:
745#ifndef CONFIG_THUMB2_KERNEL
746#ifndef DEBUG
747		orr	r0, r0, #0x000d		@ Write buffer, mmu
748#endif
749		mov	r1, #-1
750		mcr	p15, 0, r3, c2, c0, 0	@ load page table pointer
751		mcr	p15, 0, r1, c3, c0, 0	@ load domain access control
752		b	1f
753		.align	5			@ cache line aligned
7541:		mcr	p15, 0, r0, c1, c0, 0	@ load control register
755		mrc	p15, 0, r0, c1, c0, 0	@ and read it back to
756		sub	pc, lr, r0, lsr #32	@ properly flush pipeline
757#endif
758
759#define PROC_ENTRY_SIZE (4*5)
760
761/*
762 * Here follow the relocatable cache support functions for the
763 * various processors.  This is a generic hook for locating an
764 * entry and jumping to an instruction at the specified offset
765 * from the start of the block.  Please note this is all position
766 * independent code.
767 *
768 *  r1  = corrupted
769 *  r2  = corrupted
770 *  r3  = block offset
771 *  r9  = corrupted
772 *  r12 = corrupted
773 */
774
775call_cache_fn:	adr	r12, proc_types
776#ifdef CONFIG_CPU_CP15
777		mrc	p15, 0, r9, c0, c0	@ get processor ID
778#else
779		ldr	r9, =CONFIG_PROCESSOR_ID
780#endif
7811:		ldr	r1, [r12, #0]		@ get value
782		ldr	r2, [r12, #4]		@ get mask
783		eor	r1, r1, r9		@ (real ^ match)
784		tst	r1, r2			@       & mask
785 ARM(		addeq	pc, r12, r3		) @ call cache function
786 THUMB(		addeq	r12, r3			)
787 THUMB(		moveq	pc, r12			) @ call cache function
788		add	r12, r12, #PROC_ENTRY_SIZE
789		b	1b
790
791/*
792 * Table for cache operations.  This is basically:
793 *   - CPU ID match
794 *   - CPU ID mask
795 *   - 'cache on' method instruction
796 *   - 'cache off' method instruction
797 *   - 'cache flush' method instruction
798 *
799 * We match an entry using: ((real_id ^ match) & mask) == 0
800 *
801 * Writethrough caches generally only need 'on' and 'off'
802 * methods.  Writeback caches _must_ have the flush method
803 * defined.
804 */
805		.align	2
806		.type	proc_types,#object
807proc_types:
808		.word	0x00000000		@ old ARM ID
809		.word	0x0000f000
810		mov	pc, lr
811 THUMB(		nop				)
812		mov	pc, lr
813 THUMB(		nop				)
814		mov	pc, lr
815 THUMB(		nop				)
816
817		.word	0x41007000		@ ARM7/710
818		.word	0xfff8fe00
819		mov	pc, lr
820 THUMB(		nop				)
821		mov	pc, lr
822 THUMB(		nop				)
823		mov	pc, lr
824 THUMB(		nop				)
825
826		.word	0x41807200		@ ARM720T (writethrough)
827		.word	0xffffff00
828		W(b)	__armv4_mmu_cache_on
829		W(b)	__armv4_mmu_cache_off
830		mov	pc, lr
831 THUMB(		nop				)
832
833		.word	0x41007400		@ ARM74x
834		.word	0xff00ff00
835		W(b)	__armv3_mpu_cache_on
836		W(b)	__armv3_mpu_cache_off
837		W(b)	__armv3_mpu_cache_flush
838
839		.word	0x41009400		@ ARM94x
840		.word	0xff00ff00
841		W(b)	__armv4_mpu_cache_on
842		W(b)	__armv4_mpu_cache_off
843		W(b)	__armv4_mpu_cache_flush
844
845		.word	0x41069260		@ ARM926EJ-S (v5TEJ)
846		.word	0xff0ffff0
847		W(b)	__arm926ejs_mmu_cache_on
848		W(b)	__armv4_mmu_cache_off
849		W(b)	__armv5tej_mmu_cache_flush
850
851		.word	0x00007000		@ ARM7 IDs
852		.word	0x0000f000
853		mov	pc, lr
854 THUMB(		nop				)
855		mov	pc, lr
856 THUMB(		nop				)
857		mov	pc, lr
858 THUMB(		nop				)
859
860		@ Everything from here on will be the new ID system.
861
862		.word	0x4401a100		@ sa110 / sa1100
863		.word	0xffffffe0
864		W(b)	__armv4_mmu_cache_on
865		W(b)	__armv4_mmu_cache_off
866		W(b)	__armv4_mmu_cache_flush
867
868		.word	0x6901b110		@ sa1110
869		.word	0xfffffff0
870		W(b)	__armv4_mmu_cache_on
871		W(b)	__armv4_mmu_cache_off
872		W(b)	__armv4_mmu_cache_flush
873
874		.word	0x56056900
875		.word	0xffffff00		@ PXA9xx
876		W(b)	__armv4_mmu_cache_on
877		W(b)	__armv4_mmu_cache_off
878		W(b)	__armv4_mmu_cache_flush
879
880		.word	0x56158000		@ PXA168
881		.word	0xfffff000
882		W(b)	__armv4_mmu_cache_on
883		W(b)	__armv4_mmu_cache_off
884		W(b)	__armv5tej_mmu_cache_flush
885
886		.word	0x56050000		@ Feroceon
887		.word	0xff0f0000
888		W(b)	__armv4_mmu_cache_on
889		W(b)	__armv4_mmu_cache_off
890		W(b)	__armv5tej_mmu_cache_flush
891
892#ifdef CONFIG_CPU_FEROCEON_OLD_ID
893		/* this conflicts with the standard ARMv5TE entry */
894		.long	0x41009260		@ Old Feroceon
895		.long	0xff00fff0
896		b	__armv4_mmu_cache_on
897		b	__armv4_mmu_cache_off
898		b	__armv5tej_mmu_cache_flush
899#endif
900
901		.word	0x66015261		@ FA526
902		.word	0xff01fff1
903		W(b)	__fa526_cache_on
904		W(b)	__armv4_mmu_cache_off
905		W(b)	__fa526_cache_flush
906
907		@ These match on the architecture ID
908
909		.word	0x00020000		@ ARMv4T
910		.word	0x000f0000
911		W(b)	__armv4_mmu_cache_on
912		W(b)	__armv4_mmu_cache_off
913		W(b)	__armv4_mmu_cache_flush
914
915		.word	0x00050000		@ ARMv5TE
916		.word	0x000f0000
917		W(b)	__armv4_mmu_cache_on
918		W(b)	__armv4_mmu_cache_off
919		W(b)	__armv4_mmu_cache_flush
920
921		.word	0x00060000		@ ARMv5TEJ
922		.word	0x000f0000
923		W(b)	__armv4_mmu_cache_on
924		W(b)	__armv4_mmu_cache_off
925		W(b)	__armv5tej_mmu_cache_flush
926
927		.word	0x0007b000		@ ARMv6
928		.word	0x000ff000
929		W(b)	__armv6_mmu_cache_on
930		W(b)	__armv4_mmu_cache_off
931		W(b)	__armv6_mmu_cache_flush
932
933		.word	0x000f0000		@ new CPU Id
934		.word	0x000f0000
935		W(b)	__armv7_mmu_cache_on
936		W(b)	__armv7_mmu_cache_off
937		W(b)	__armv7_mmu_cache_flush
938
939		.word	0			@ unrecognised type
940		.word	0
941		mov	pc, lr
942 THUMB(		nop				)
943		mov	pc, lr
944 THUMB(		nop				)
945		mov	pc, lr
946 THUMB(		nop				)
947
948		.size	proc_types, . - proc_types
949
950		/*
951		 * If you get a "non-constant expression in ".if" statement"
952		 * error from the assembler on this line, check that you have
953		 * not accidentally written a "b" instruction where you should
954		 * have written W(b).
955		 */
956		.if (. - proc_types) % PROC_ENTRY_SIZE != 0
957		.error "The size of one or more proc_types entries is wrong."
958		.endif
959
960/*
961 * Turn off the Cache and MMU.  ARMv3 does not support
962 * reading the control register, but ARMv4 does.
963 *
964 * On exit,
965 *  r0, r1, r2, r3, r9, r12 corrupted
966 * This routine must preserve:
967 *  r4, r7, r8
968 */
969		.align	5
970cache_off:	mov	r3, #12			@ cache_off function
971		b	call_cache_fn
972
973__armv4_mpu_cache_off:
974		mrc	p15, 0, r0, c1, c0
975		bic	r0, r0, #0x000d
976		mcr	p15, 0, r0, c1, c0	@ turn MPU and cache off
977		mov	r0, #0
978		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
979		mcr	p15, 0, r0, c7, c6, 0	@ flush D-Cache
980		mcr	p15, 0, r0, c7, c5, 0	@ flush I-Cache
981		mov	pc, lr
982
983__armv3_mpu_cache_off:
984		mrc	p15, 0, r0, c1, c0
985		bic	r0, r0, #0x000d
986		mcr	p15, 0, r0, c1, c0, 0	@ turn MPU and cache off
987		mov	r0, #0
988		mcr	p15, 0, r0, c7, c0, 0	@ invalidate whole cache v3
989		mov	pc, lr
990
991__armv4_mmu_cache_off:
992#ifdef CONFIG_MMU
993		mrc	p15, 0, r0, c1, c0
994		bic	r0, r0, #0x000d
995		mcr	p15, 0, r0, c1, c0	@ turn MMU and cache off
996		mov	r0, #0
997		mcr	p15, 0, r0, c7, c7	@ invalidate whole cache v4
998		mcr	p15, 0, r0, c8, c7	@ invalidate whole TLB v4
999#endif
1000		mov	pc, lr
1001
1002__armv7_mmu_cache_off:
1003		mrc	p15, 0, r0, c1, c0
1004#ifdef CONFIG_MMU
1005		bic	r0, r0, #0x000d
1006#else
1007		bic	r0, r0, #0x000c
1008#endif
1009		mcr	p15, 0, r0, c1, c0	@ turn MMU and cache off
1010		mov	r12, lr
1011		bl	__armv7_mmu_cache_flush
1012		mov	r0, #0
1013#ifdef CONFIG_MMU
1014		mcr	p15, 0, r0, c8, c7, 0	@ invalidate whole TLB
1015#endif
1016		mcr	p15, 0, r0, c7, c5, 6	@ invalidate BTC
1017		mcr	p15, 0, r0, c7, c10, 4	@ DSB
1018		mcr	p15, 0, r0, c7, c5, 4	@ ISB
1019		mov	pc, r12
1020
1021/*
1022 * Clean and flush the cache to maintain consistency.
1023 *
1024 * On exit,
1025 *  r1, r2, r3, r9, r10, r11, r12 corrupted
1026 * This routine must preserve:
1027 *  r4, r6, r7, r8
1028 */
1029		.align	5
1030cache_clean_flush:
1031		mov	r3, #16
1032		b	call_cache_fn
1033
1034__armv4_mpu_cache_flush:
1035		mov	r2, #1
1036		mov	r3, #0
1037		mcr	p15, 0, ip, c7, c6, 0	@ invalidate D cache
1038		mov	r1, #7 << 5		@ 8 segments
10391:		orr	r3, r1, #63 << 26	@ 64 entries
10402:		mcr	p15, 0, r3, c7, c14, 2	@ clean & invalidate D index
1041		subs	r3, r3, #1 << 26
1042		bcs	2b			@ entries 63 to 0
1043		subs 	r1, r1, #1 << 5
1044		bcs	1b			@ segments 7 to 0
1045
1046		teq	r2, #0
1047		mcrne	p15, 0, ip, c7, c5, 0	@ invalidate I cache
1048		mcr	p15, 0, ip, c7, c10, 4	@ drain WB
1049		mov	pc, lr
1050
1051__fa526_cache_flush:
1052		mov	r1, #0
1053		mcr	p15, 0, r1, c7, c14, 0	@ clean and invalidate D cache
1054		mcr	p15, 0, r1, c7, c5, 0	@ flush I cache
1055		mcr	p15, 0, r1, c7, c10, 4	@ drain WB
1056		mov	pc, lr
1057
1058__armv6_mmu_cache_flush:
1059		mov	r1, #0
1060		mcr	p15, 0, r1, c7, c14, 0	@ clean+invalidate D
1061		mcr	p15, 0, r1, c7, c5, 0	@ invalidate I+BTB
1062		mcr	p15, 0, r1, c7, c15, 0	@ clean+invalidate unified
1063		mcr	p15, 0, r1, c7, c10, 4	@ drain WB
1064		mov	pc, lr
1065
1066__armv7_mmu_cache_flush:
1067		mrc	p15, 0, r10, c0, c1, 5	@ read ID_MMFR1
1068		tst	r10, #0xf << 16		@ hierarchical cache (ARMv7)
1069		mov	r10, #0
1070		beq	hierarchical
1071		mcr	p15, 0, r10, c7, c14, 0	@ clean+invalidate D
1072		b	iflush
1073hierarchical:
1074		mcr	p15, 0, r10, c7, c10, 5	@ DMB
1075		stmfd	sp!, {r0-r7, r9-r11}
1076		mrc	p15, 1, r0, c0, c0, 1	@ read clidr
1077		ands	r3, r0, #0x7000000	@ extract loc from clidr
1078		mov	r3, r3, lsr #23		@ left align loc bit field
1079		beq	finished		@ if loc is 0, then no need to clean
1080		mov	r10, #0			@ start clean at cache level 0
1081loop1:
1082		add	r2, r10, r10, lsr #1	@ work out 3x current cache level
1083		mov	r1, r0, lsr r2		@ extract cache type bits from clidr
1084		and	r1, r1, #7		@ mask of the bits for current cache only
1085		cmp	r1, #2			@ see what cache we have at this level
1086		blt	skip			@ skip if no cache, or just i-cache
1087		mcr	p15, 2, r10, c0, c0, 0	@ select current cache level in cssr
1088		mcr	p15, 0, r10, c7, c5, 4	@ isb to sych the new cssr&csidr
1089		mrc	p15, 1, r1, c0, c0, 0	@ read the new csidr
1090		and	r2, r1, #7		@ extract the length of the cache lines
1091		add	r2, r2, #4		@ add 4 (line length offset)
1092		ldr	r4, =0x3ff
1093		ands	r4, r4, r1, lsr #3	@ find maximum number on the way size
1094		clz	r5, r4			@ find bit position of way size increment
1095		ldr	r7, =0x7fff
1096		ands	r7, r7, r1, lsr #13	@ extract max number of the index size
1097loop2:
1098		mov	r9, r4			@ create working copy of max way size
1099loop3:
1100 ARM(		orr	r11, r10, r9, lsl r5	) @ factor way and cache number into r11
1101 ARM(		orr	r11, r11, r7, lsl r2	) @ factor index number into r11
1102 THUMB(		lsl	r6, r9, r5		)
1103 THUMB(		orr	r11, r10, r6		) @ factor way and cache number into r11
1104 THUMB(		lsl	r6, r7, r2		)
1105 THUMB(		orr	r11, r11, r6		) @ factor index number into r11
1106		mcr	p15, 0, r11, c7, c14, 2	@ clean & invalidate by set/way
1107		subs	r9, r9, #1		@ decrement the way
1108		bge	loop3
1109		subs	r7, r7, #1		@ decrement the index
1110		bge	loop2
1111skip:
1112		add	r10, r10, #2		@ increment cache number
1113		cmp	r3, r10
1114		bgt	loop1
1115finished:
1116		ldmfd	sp!, {r0-r7, r9-r11}
1117		mov	r10, #0			@ swith back to cache level 0
1118		mcr	p15, 2, r10, c0, c0, 0	@ select current cache level in cssr
1119iflush:
1120		mcr	p15, 0, r10, c7, c10, 4	@ DSB
1121		mcr	p15, 0, r10, c7, c5, 0	@ invalidate I+BTB
1122		mcr	p15, 0, r10, c7, c10, 4	@ DSB
1123		mcr	p15, 0, r10, c7, c5, 4	@ ISB
1124		mov	pc, lr
1125
1126__armv5tej_mmu_cache_flush:
11271:		mrc	p15, 0, r15, c7, c14, 3	@ test,clean,invalidate D cache
1128		bne	1b
1129		mcr	p15, 0, r0, c7, c5, 0	@ flush I cache
1130		mcr	p15, 0, r0, c7, c10, 4	@ drain WB
1131		mov	pc, lr
1132
1133__armv4_mmu_cache_flush:
1134		mov	r2, #64*1024		@ default: 32K dcache size (*2)
1135		mov	r11, #32		@ default: 32 byte line size
1136		mrc	p15, 0, r3, c0, c0, 1	@ read cache type
1137		teq	r3, r9			@ cache ID register present?
1138		beq	no_cache_id
1139		mov	r1, r3, lsr #18
1140		and	r1, r1, #7
1141		mov	r2, #1024
1142		mov	r2, r2, lsl r1		@ base dcache size *2
1143		tst	r3, #1 << 14		@ test M bit
1144		addne	r2, r2, r2, lsr #1	@ +1/2 size if M == 1
1145		mov	r3, r3, lsr #12
1146		and	r3, r3, #3
1147		mov	r11, #8
1148		mov	r11, r11, lsl r3	@ cache line size in bytes
1149no_cache_id:
1150		mov	r1, pc
1151		bic	r1, r1, #63		@ align to longest cache line
1152		add	r2, r1, r2
11531:
1154 ARM(		ldr	r3, [r1], r11		) @ s/w flush D cache
1155 THUMB(		ldr     r3, [r1]		) @ s/w flush D cache
1156 THUMB(		add     r1, r1, r11		)
1157		teq	r1, r2
1158		bne	1b
1159
1160		mcr	p15, 0, r1, c7, c5, 0	@ flush I cache
1161		mcr	p15, 0, r1, c7, c6, 0	@ flush D cache
1162		mcr	p15, 0, r1, c7, c10, 4	@ drain WB
1163		mov	pc, lr
1164
1165__armv3_mmu_cache_flush:
1166__armv3_mpu_cache_flush:
1167		mov	r1, #0
1168		mcr	p15, 0, r1, c7, c0, 0	@ invalidate whole cache v3
1169		mov	pc, lr
1170
1171/*
1172 * Various debugging routines for printing hex characters and
1173 * memory, which again must be relocatable.
1174 */
1175#ifdef DEBUG
1176		.align	2
1177		.type	phexbuf,#object
1178phexbuf:	.space	12
1179		.size	phexbuf, . - phexbuf
1180
1181@ phex corrupts {r0, r1, r2, r3}
1182phex:		adr	r3, phexbuf
1183		mov	r2, #0
1184		strb	r2, [r3, r1]
11851:		subs	r1, r1, #1
1186		movmi	r0, r3
1187		bmi	puts
1188		and	r2, r0, #15
1189		mov	r0, r0, lsr #4
1190		cmp	r2, #10
1191		addge	r2, r2, #7
1192		add	r2, r2, #'0'
1193		strb	r2, [r3, r1]
1194		b	1b
1195
1196@ puts corrupts {r0, r1, r2, r3}
1197puts:		loadsp	r3, r1
11981:		ldrb	r2, [r0], #1
1199		teq	r2, #0
1200		moveq	pc, lr
12012:		writeb	r2, r3
1202		mov	r1, #0x00020000
12033:		subs	r1, r1, #1
1204		bne	3b
1205		teq	r2, #'\n'
1206		moveq	r2, #'\r'
1207		beq	2b
1208		teq	r0, #0
1209		bne	1b
1210		mov	pc, lr
1211@ putc corrupts {r0, r1, r2, r3}
1212putc:
1213		mov	r2, r0
1214		mov	r0, #0
1215		loadsp	r3, r1
1216		b	2b
1217
1218@ memdump corrupts {r0, r1, r2, r3, r10, r11, r12, lr}
1219memdump:	mov	r12, r0
1220		mov	r10, lr
1221		mov	r11, #0
12222:		mov	r0, r11, lsl #2
1223		add	r0, r0, r12
1224		mov	r1, #8
1225		bl	phex
1226		mov	r0, #':'
1227		bl	putc
12281:		mov	r0, #' '
1229		bl	putc
1230		ldr	r0, [r12, r11, lsl #2]
1231		mov	r1, #8
1232		bl	phex
1233		and	r0, r11, #7
1234		teq	r0, #3
1235		moveq	r0, #' '
1236		bleq	putc
1237		and	r0, r11, #7
1238		add	r11, r11, #1
1239		teq	r0, #7
1240		bne	1b
1241		mov	r0, #'\n'
1242		bl	putc
1243		cmp	r11, #64
1244		blt	2b
1245		mov	pc, r10
1246#endif
1247
1248		.ltorg
1249
1250#ifdef CONFIG_ARM_VIRT_EXT
1251.align 5
1252__hyp_reentry_vectors:
1253		W(b)	.			@ reset
1254		W(b)	.			@ undef
1255		W(b)	.			@ svc
1256		W(b)	.			@ pabort
1257		W(b)	.			@ dabort
1258		W(b)	__enter_kernel		@ hyp
1259		W(b)	.			@ irq
1260		W(b)	.			@ fiq
1261#endif /* CONFIG_ARM_VIRT_EXT */
1262
1263__enter_kernel:
1264		mov	r0, #0			@ must be 0
1265 ARM(		mov	pc, r4	)		@ call kernel
1266 THUMB(		bx	r4	)		@ entry point is always ARM
1267
1268reloc_code_end:
1269
1270		.align
1271		.section ".stack", "aw", %nobits
1272.L_user_stack:	.space	4096
1273.L_user_stack_end:
1274