xref: /linux/arch/arm/boot/compressed/head.S (revision 95e9fd10f06cb5642028b6b851e32b8c8afb4571)
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
13/*
14 * Debugging stuff
15 *
16 * Note that these macros must not contain any code which is not
17 * 100% relocatable.  Any attempt to do so will result in a crash.
18 * Please select one of the following when turning on debugging.
19 */
20#ifdef DEBUG
21
22#if defined(CONFIG_DEBUG_ICEDCC)
23
24#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K) || defined(CONFIG_CPU_V7)
25		.macro	loadsp, rb, tmp
26		.endm
27		.macro	writeb, ch, rb
28		mcr	p14, 0, \ch, c0, c5, 0
29		.endm
30#elif defined(CONFIG_CPU_XSCALE)
31		.macro	loadsp, rb, tmp
32		.endm
33		.macro	writeb, ch, rb
34		mcr	p14, 0, \ch, c8, c0, 0
35		.endm
36#else
37		.macro	loadsp, rb, tmp
38		.endm
39		.macro	writeb, ch, rb
40		mcr	p14, 0, \ch, c1, c0, 0
41		.endm
42#endif
43
44#else
45
46#include <mach/debug-macro.S>
47
48		.macro	writeb,	ch, rb
49		senduart \ch, \rb
50		.endm
51
52#if defined(CONFIG_ARCH_SA1100)
53		.macro	loadsp, rb, tmp
54		mov	\rb, #0x80000000	@ physical base address
55#ifdef CONFIG_DEBUG_LL_SER3
56		add	\rb, \rb, #0x00050000	@ Ser3
57#else
58		add	\rb, \rb, #0x00010000	@ Ser1
59#endif
60		.endm
61#elif defined(CONFIG_ARCH_S3C24XX)
62		.macro loadsp, rb, tmp
63		mov	\rb, #0x50000000
64		add	\rb, \rb, #0x4000 * CONFIG_S3C_LOWLEVEL_UART_PORT
65		.endm
66#else
67		.macro	loadsp,	rb, tmp
68		addruart \rb, \tmp
69		.endm
70#endif
71#endif
72#endif
73
74		.macro	kputc,val
75		mov	r0, \val
76		bl	putc
77		.endm
78
79		.macro	kphex,val,len
80		mov	r0, \val
81		mov	r1, #\len
82		bl	phex
83		.endm
84
85		.macro	debug_reloc_start
86#ifdef DEBUG
87		kputc	#'\n'
88		kphex	r6, 8		/* processor id */
89		kputc	#':'
90		kphex	r7, 8		/* architecture id */
91#ifdef CONFIG_CPU_CP15
92		kputc	#':'
93		mrc	p15, 0, r0, c1, c0
94		kphex	r0, 8		/* control reg */
95#endif
96		kputc	#'\n'
97		kphex	r5, 8		/* decompressed kernel start */
98		kputc	#'-'
99		kphex	r9, 8		/* decompressed kernel end  */
100		kputc	#'>'
101		kphex	r4, 8		/* kernel execution address */
102		kputc	#'\n'
103#endif
104		.endm
105
106		.macro	debug_reloc_end
107#ifdef DEBUG
108		kphex	r5, 8		/* end of kernel */
109		kputc	#'\n'
110		mov	r0, r4
111		bl	memdump		/* dump 256 bytes at start of kernel */
112#endif
113		.endm
114
115		.section ".start", #alloc, #execinstr
116/*
117 * sort out different calling conventions
118 */
119		.align
120		.arm				@ Always enter in ARM state
121start:
122		.type	start,#function
123		.rept	7
124		mov	r0, r0
125		.endr
126   ARM(		mov	r0, r0		)
127   ARM(		b	1f		)
128 THUMB(		adr	r12, BSYM(1f)	)
129 THUMB(		bx	r12		)
130
131		.word	0x016f2818		@ Magic numbers to help the loader
132		.word	start			@ absolute load/run zImage address
133		.word	_edata			@ zImage end address
134 THUMB(		.thumb			)
1351:		mov	r7, r1			@ save architecture ID
136		mov	r8, r2			@ save atags pointer
137
138#ifndef __ARM_ARCH_2__
139		/*
140		 * Booting from Angel - need to enter SVC mode and disable
141		 * FIQs/IRQs (numeric definitions from angel arm.h source).
142		 * We only do this if we were in user mode on entry.
143		 */
144		mrs	r2, cpsr		@ get current mode
145		tst	r2, #3			@ not user?
146		bne	not_angel
147		mov	r0, #0x17		@ angel_SWIreason_EnterSVC
148 ARM(		swi	0x123456	)	@ angel_SWI_ARM
149 THUMB(		svc	0xab		)	@ angel_SWI_THUMB
150not_angel:
151		mrs	r2, cpsr		@ turn off interrupts to
152		orr	r2, r2, #0xc0		@ prevent angel from running
153		msr	cpsr_c, r2
154#else
155		teqp	pc, #0x0c000003		@ turn off interrupts
156#endif
157
158		/*
159		 * Note that some cache flushing and other stuff may
160		 * be needed here - is there an Angel SWI call for this?
161		 */
162
163		/*
164		 * some architecture specific code can be inserted
165		 * by the linker here, but it should preserve r7, r8, and r9.
166		 */
167
168		.text
169
170#ifdef CONFIG_AUTO_ZRELADDR
171		@ determine final kernel image address
172		mov	r4, pc
173		and	r4, r4, #0xf8000000
174		add	r4, r4, #TEXT_OFFSET
175#else
176		ldr	r4, =zreladdr
177#endif
178
179		bl	cache_on
180
181restart:	adr	r0, LC0
182		ldmia	r0, {r1, r2, r3, r6, r10, r11, r12}
183		ldr	sp, [r0, #28]
184
185		/*
186		 * We might be running at a different address.  We need
187		 * to fix up various pointers.
188		 */
189		sub	r0, r0, r1		@ calculate the delta offset
190		add	r6, r6, r0		@ _edata
191		add	r10, r10, r0		@ inflated kernel size location
192
193		/*
194		 * The kernel build system appends the size of the
195		 * decompressed kernel at the end of the compressed data
196		 * in little-endian form.
197		 */
198		ldrb	r9, [r10, #0]
199		ldrb	lr, [r10, #1]
200		orr	r9, r9, lr, lsl #8
201		ldrb	lr, [r10, #2]
202		ldrb	r10, [r10, #3]
203		orr	r9, r9, lr, lsl #16
204		orr	r9, r9, r10, lsl #24
205
206#ifndef CONFIG_ZBOOT_ROM
207		/* malloc space is above the relocated stack (64k max) */
208		add	sp, sp, r0
209		add	r10, sp, #0x10000
210#else
211		/*
212		 * With ZBOOT_ROM the bss/stack is non relocatable,
213		 * but someone could still run this code from RAM,
214		 * in which case our reference is _edata.
215		 */
216		mov	r10, r6
217#endif
218
219		mov	r5, #0			@ init dtb size to 0
220#ifdef CONFIG_ARM_APPENDED_DTB
221/*
222 *   r0  = delta
223 *   r2  = BSS start
224 *   r3  = BSS end
225 *   r4  = final kernel address
226 *   r5  = appended dtb size (still unknown)
227 *   r6  = _edata
228 *   r7  = architecture ID
229 *   r8  = atags/device tree pointer
230 *   r9  = size of decompressed image
231 *   r10 = end of this image, including  bss/stack/malloc space if non XIP
232 *   r11 = GOT start
233 *   r12 = GOT end
234 *   sp  = stack pointer
235 *
236 * if there are device trees (dtb) appended to zImage, advance r10 so that the
237 * dtb data will get relocated along with the kernel if necessary.
238 */
239
240		ldr	lr, [r6, #0]
241#ifndef __ARMEB__
242		ldr	r1, =0xedfe0dd0		@ sig is 0xd00dfeed big endian
243#else
244		ldr	r1, =0xd00dfeed
245#endif
246		cmp	lr, r1
247		bne	dtb_check_done		@ not found
248
249#ifdef CONFIG_ARM_ATAG_DTB_COMPAT
250		/*
251		 * OK... Let's do some funky business here.
252		 * If we do have a DTB appended to zImage, and we do have
253		 * an ATAG list around, we want the later to be translated
254		 * and folded into the former here.  To be on the safe side,
255		 * let's temporarily move  the stack away into the malloc
256		 * area.  No GOT fixup has occurred yet, but none of the
257		 * code we're about to call uses any global variable.
258		*/
259		add	sp, sp, #0x10000
260		stmfd	sp!, {r0-r3, ip, lr}
261		mov	r0, r8
262		mov	r1, r6
263		sub	r2, sp, r6
264		bl	atags_to_fdt
265
266		/*
267		 * If returned value is 1, there is no ATAG at the location
268		 * pointed by r8.  Try the typical 0x100 offset from start
269		 * of RAM and hope for the best.
270		 */
271		cmp	r0, #1
272		sub	r0, r4, #TEXT_OFFSET
273		add	r0, r0, #0x100
274		mov	r1, r6
275		sub	r2, sp, r6
276		bleq	atags_to_fdt
277
278		ldmfd	sp!, {r0-r3, ip, lr}
279		sub	sp, sp, #0x10000
280#endif
281
282		mov	r8, r6			@ use the appended device tree
283
284		/*
285		 * Make sure that the DTB doesn't end up in the final
286		 * kernel's .bss area. To do so, we adjust the decompressed
287		 * kernel size to compensate if that .bss size is larger
288		 * than the relocated code.
289		 */
290		ldr	r5, =_kernel_bss_size
291		adr	r1, wont_overwrite
292		sub	r1, r6, r1
293		subs	r1, r5, r1
294		addhi	r9, r9, r1
295
296		/* Get the dtb's size */
297		ldr	r5, [r6, #4]
298#ifndef __ARMEB__
299		/* convert r5 (dtb size) to little endian */
300		eor	r1, r5, r5, ror #16
301		bic	r1, r1, #0x00ff0000
302		mov	r5, r5, ror #8
303		eor	r5, r5, r1, lsr #8
304#endif
305
306		/* preserve 64-bit alignment */
307		add	r5, r5, #7
308		bic	r5, r5, #7
309
310		/* relocate some pointers past the appended dtb */
311		add	r6, r6, r5
312		add	r10, r10, r5
313		add	sp, sp, r5
314dtb_check_done:
315#endif
316
317/*
318 * Check to see if we will overwrite ourselves.
319 *   r4  = final kernel address
320 *   r9  = size of decompressed image
321 *   r10 = end of this image, including  bss/stack/malloc space if non XIP
322 * We basically want:
323 *   r4 - 16k page directory >= r10 -> OK
324 *   r4 + image length <= address of wont_overwrite -> OK
325 */
326		add	r10, r10, #16384
327		cmp	r4, r10
328		bhs	wont_overwrite
329		add	r10, r4, r9
330		adr	r9, wont_overwrite
331		cmp	r10, r9
332		bls	wont_overwrite
333
334/*
335 * Relocate ourselves past the end of the decompressed kernel.
336 *   r6  = _edata
337 *   r10 = end of the decompressed kernel
338 * Because we always copy ahead, we need to do it from the end and go
339 * backward in case the source and destination overlap.
340 */
341		/*
342		 * Bump to the next 256-byte boundary with the size of
343		 * the relocation code added. This avoids overwriting
344		 * ourself when the offset is small.
345		 */
346		add	r10, r10, #((reloc_code_end - restart + 256) & ~255)
347		bic	r10, r10, #255
348
349		/* Get start of code we want to copy and align it down. */
350		adr	r5, restart
351		bic	r5, r5, #31
352
353		sub	r9, r6, r5		@ size to copy
354		add	r9, r9, #31		@ rounded up to a multiple
355		bic	r9, r9, #31		@ ... of 32 bytes
356		add	r6, r9, r5
357		add	r9, r9, r10
358
3591:		ldmdb	r6!, {r0 - r3, r10 - r12, lr}
360		cmp	r6, r5
361		stmdb	r9!, {r0 - r3, r10 - r12, lr}
362		bhi	1b
363
364		/* Preserve offset to relocated code. */
365		sub	r6, r9, r6
366
367#ifndef CONFIG_ZBOOT_ROM
368		/* cache_clean_flush may use the stack, so relocate it */
369		add	sp, sp, r6
370#endif
371
372		bl	cache_clean_flush
373
374		adr	r0, BSYM(restart)
375		add	r0, r0, r6
376		mov	pc, r0
377
378wont_overwrite:
379/*
380 * If delta is zero, we are running at the address we were linked at.
381 *   r0  = delta
382 *   r2  = BSS start
383 *   r3  = BSS end
384 *   r4  = kernel execution address
385 *   r5  = appended dtb size (0 if not present)
386 *   r7  = architecture ID
387 *   r8  = atags pointer
388 *   r11 = GOT start
389 *   r12 = GOT end
390 *   sp  = stack pointer
391 */
392		orrs	r1, r0, r5
393		beq	not_relocated
394
395		add	r11, r11, r0
396		add	r12, r12, r0
397
398#ifndef CONFIG_ZBOOT_ROM
399		/*
400		 * If we're running fully PIC === CONFIG_ZBOOT_ROM = n,
401		 * we need to fix up pointers into the BSS region.
402		 * Note that the stack pointer has already been fixed up.
403		 */
404		add	r2, r2, r0
405		add	r3, r3, r0
406
407		/*
408		 * Relocate all entries in the GOT table.
409		 * Bump bss entries to _edata + dtb size
410		 */
4111:		ldr	r1, [r11, #0]		@ relocate entries in the GOT
412		add	r1, r1, r0		@ This fixes up C references
413		cmp	r1, r2			@ if entry >= bss_start &&
414		cmphs	r3, r1			@       bss_end > entry
415		addhi	r1, r1, r5		@    entry += dtb size
416		str	r1, [r11], #4		@ next entry
417		cmp	r11, r12
418		blo	1b
419
420		/* bump our bss pointers too */
421		add	r2, r2, r5
422		add	r3, r3, r5
423
424#else
425
426		/*
427		 * Relocate entries in the GOT table.  We only relocate
428		 * the entries that are outside the (relocated) BSS region.
429		 */
4301:		ldr	r1, [r11, #0]		@ relocate entries in the GOT
431		cmp	r1, r2			@ entry < bss_start ||
432		cmphs	r3, r1			@ _end < entry
433		addlo	r1, r1, r0		@ table.  This fixes up the
434		str	r1, [r11], #4		@ C references.
435		cmp	r11, r12
436		blo	1b
437#endif
438
439not_relocated:	mov	r0, #0
4401:		str	r0, [r2], #4		@ clear bss
441		str	r0, [r2], #4
442		str	r0, [r2], #4
443		str	r0, [r2], #4
444		cmp	r2, r3
445		blo	1b
446
447/*
448 * The C runtime environment should now be setup sufficiently.
449 * Set up some pointers, and start decompressing.
450 *   r4  = kernel execution address
451 *   r7  = architecture ID
452 *   r8  = atags pointer
453 */
454		mov	r0, r4
455		mov	r1, sp			@ malloc space above stack
456		add	r2, sp, #0x10000	@ 64k max
457		mov	r3, r7
458		bl	decompress_kernel
459		bl	cache_clean_flush
460		bl	cache_off
461		mov	r0, #0			@ must be zero
462		mov	r1, r7			@ restore architecture number
463		mov	r2, r8			@ restore atags pointer
464 ARM(		mov	pc, r4	)		@ call kernel
465 THUMB(		bx	r4	)		@ entry point is always ARM
466
467		.align	2
468		.type	LC0, #object
469LC0:		.word	LC0			@ r1
470		.word	__bss_start		@ r2
471		.word	_end			@ r3
472		.word	_edata			@ r6
473		.word	input_data_end - 4	@ r10 (inflated size location)
474		.word	_got_start		@ r11
475		.word	_got_end		@ ip
476		.word	.L_user_stack_end	@ sp
477		.size	LC0, . - LC0
478
479#ifdef CONFIG_ARCH_RPC
480		.globl	params
481params:		ldr	r0, =0x10000100		@ params_phys for RPC
482		mov	pc, lr
483		.ltorg
484		.align
485#endif
486
487/*
488 * Turn on the cache.  We need to setup some page tables so that we
489 * can have both the I and D caches on.
490 *
491 * We place the page tables 16k down from the kernel execution address,
492 * and we hope that nothing else is using it.  If we're using it, we
493 * will go pop!
494 *
495 * On entry,
496 *  r4 = kernel execution address
497 *  r7 = architecture number
498 *  r8 = atags pointer
499 * On exit,
500 *  r0, r1, r2, r3, r9, r10, r12 corrupted
501 * This routine must preserve:
502 *  r4, r7, r8
503 */
504		.align	5
505cache_on:	mov	r3, #8			@ cache_on function
506		b	call_cache_fn
507
508/*
509 * Initialize the highest priority protection region, PR7
510 * to cover all 32bit address and cacheable and bufferable.
511 */
512__armv4_mpu_cache_on:
513		mov	r0, #0x3f		@ 4G, the whole
514		mcr	p15, 0, r0, c6, c7, 0	@ PR7 Area Setting
515		mcr 	p15, 0, r0, c6, c7, 1
516
517		mov	r0, #0x80		@ PR7
518		mcr	p15, 0, r0, c2, c0, 0	@ D-cache on
519		mcr	p15, 0, r0, c2, c0, 1	@ I-cache on
520		mcr	p15, 0, r0, c3, c0, 0	@ write-buffer on
521
522		mov	r0, #0xc000
523		mcr	p15, 0, r0, c5, c0, 1	@ I-access permission
524		mcr	p15, 0, r0, c5, c0, 0	@ D-access permission
525
526		mov	r0, #0
527		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
528		mcr	p15, 0, r0, c7, c5, 0	@ flush(inval) I-Cache
529		mcr	p15, 0, r0, c7, c6, 0	@ flush(inval) D-Cache
530		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
531						@ ...I .... ..D. WC.M
532		orr	r0, r0, #0x002d		@ .... .... ..1. 11.1
533		orr	r0, r0, #0x1000		@ ...1 .... .... ....
534
535		mcr	p15, 0, r0, c1, c0, 0	@ write control reg
536
537		mov	r0, #0
538		mcr	p15, 0, r0, c7, c5, 0	@ flush(inval) I-Cache
539		mcr	p15, 0, r0, c7, c6, 0	@ flush(inval) D-Cache
540		mov	pc, lr
541
542__armv3_mpu_cache_on:
543		mov	r0, #0x3f		@ 4G, the whole
544		mcr	p15, 0, r0, c6, c7, 0	@ PR7 Area Setting
545
546		mov	r0, #0x80		@ PR7
547		mcr	p15, 0, r0, c2, c0, 0	@ cache on
548		mcr	p15, 0, r0, c3, c0, 0	@ write-buffer on
549
550		mov	r0, #0xc000
551		mcr	p15, 0, r0, c5, c0, 0	@ access permission
552
553		mov	r0, #0
554		mcr	p15, 0, r0, c7, c0, 0	@ invalidate whole cache v3
555		/*
556		 * ?? ARMv3 MMU does not allow reading the control register,
557		 * does this really work on ARMv3 MPU?
558		 */
559		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
560						@ .... .... .... WC.M
561		orr	r0, r0, #0x000d		@ .... .... .... 11.1
562		/* ?? this overwrites the value constructed above? */
563		mov	r0, #0
564		mcr	p15, 0, r0, c1, c0, 0	@ write control reg
565
566		/* ?? invalidate for the second time? */
567		mcr	p15, 0, r0, c7, c0, 0	@ invalidate whole cache v3
568		mov	pc, lr
569
570#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
571#define CB_BITS 0x08
572#else
573#define CB_BITS 0x0c
574#endif
575
576__setup_mmu:	sub	r3, r4, #16384		@ Page directory size
577		bic	r3, r3, #0xff		@ Align the pointer
578		bic	r3, r3, #0x3f00
579/*
580 * Initialise the page tables, turning on the cacheable and bufferable
581 * bits for the RAM area only.
582 */
583		mov	r0, r3
584		mov	r9, r0, lsr #18
585		mov	r9, r9, lsl #18		@ start of RAM
586		add	r10, r9, #0x10000000	@ a reasonable RAM size
587		mov	r1, #0x12		@ XN|U + section mapping
588		orr	r1, r1, #3 << 10	@ AP=11
589		add	r2, r3, #16384
5901:		cmp	r1, r9			@ if virt > start of RAM
591		cmphs	r10, r1			@   && end of RAM > virt
592		bic	r1, r1, #0x1c		@ clear XN|U + C + B
593		orrlo	r1, r1, #0x10		@ Set XN|U for non-RAM
594		orrhs	r1, r1, r6		@ set RAM section settings
595		str	r1, [r0], #4		@ 1:1 mapping
596		add	r1, r1, #1048576
597		teq	r0, r2
598		bne	1b
599/*
600 * If ever we are running from Flash, then we surely want the cache
601 * to be enabled also for our execution instance...  We map 2MB of it
602 * so there is no map overlap problem for up to 1 MB compressed kernel.
603 * If the execution is in RAM then we would only be duplicating the above.
604 */
605		orr	r1, r6, #0x04		@ ensure B is set for this
606		orr	r1, r1, #3 << 10
607		mov	r2, pc
608		mov	r2, r2, lsr #20
609		orr	r1, r1, r2, lsl #20
610		add	r0, r3, r2, lsl #2
611		str	r1, [r0], #4
612		add	r1, r1, #1048576
613		str	r1, [r0]
614		mov	pc, lr
615ENDPROC(__setup_mmu)
616
617__arm926ejs_mmu_cache_on:
618#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
619		mov	r0, #4			@ put dcache in WT mode
620		mcr	p15, 7, r0, c15, c0, 0
621#endif
622
623__armv4_mmu_cache_on:
624		mov	r12, lr
625#ifdef CONFIG_MMU
626		mov	r6, #CB_BITS | 0x12	@ U
627		bl	__setup_mmu
628		mov	r0, #0
629		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
630		mcr	p15, 0, r0, c8, c7, 0	@ flush I,D TLBs
631		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
632		orr	r0, r0, #0x5000		@ I-cache enable, RR cache replacement
633		orr	r0, r0, #0x0030
634#ifdef CONFIG_CPU_ENDIAN_BE8
635		orr	r0, r0, #1 << 25	@ big-endian page tables
636#endif
637		bl	__common_mmu_cache_on
638		mov	r0, #0
639		mcr	p15, 0, r0, c8, c7, 0	@ flush I,D TLBs
640#endif
641		mov	pc, r12
642
643__armv7_mmu_cache_on:
644		mov	r12, lr
645#ifdef CONFIG_MMU
646		mrc	p15, 0, r11, c0, c1, 4	@ read ID_MMFR0
647		tst	r11, #0xf		@ VMSA
648		movne	r6, #CB_BITS | 0x02	@ !XN
649		blne	__setup_mmu
650		mov	r0, #0
651		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
652		tst	r11, #0xf		@ VMSA
653		mcrne	p15, 0, r0, c8, c7, 0	@ flush I,D TLBs
654#endif
655		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
656		orr	r0, r0, #0x5000		@ I-cache enable, RR cache replacement
657		orr	r0, r0, #0x003c		@ write buffer
658#ifdef CONFIG_MMU
659#ifdef CONFIG_CPU_ENDIAN_BE8
660		orr	r0, r0, #1 << 25	@ big-endian page tables
661#endif
662		orrne	r0, r0, #1		@ MMU enabled
663		movne	r1, #0xfffffffd		@ domain 0 = client
664		mcrne	p15, 0, r3, c2, c0, 0	@ load page table pointer
665		mcrne	p15, 0, r1, c3, c0, 0	@ load domain access control
666#endif
667		mcr	p15, 0, r0, c7, c5, 4	@ ISB
668		mcr	p15, 0, r0, c1, c0, 0	@ load control register
669		mrc	p15, 0, r0, c1, c0, 0	@ and read it back
670		mov	r0, #0
671		mcr	p15, 0, r0, c7, c5, 4	@ ISB
672		mov	pc, r12
673
674__fa526_cache_on:
675		mov	r12, lr
676		mov	r6, #CB_BITS | 0x12	@ U
677		bl	__setup_mmu
678		mov	r0, #0
679		mcr	p15, 0, r0, c7, c7, 0	@ Invalidate whole cache
680		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
681		mcr	p15, 0, r0, c8, c7, 0	@ flush UTLB
682		mrc	p15, 0, r0, c1, c0, 0	@ read control reg
683		orr	r0, r0, #0x1000		@ I-cache enable
684		bl	__common_mmu_cache_on
685		mov	r0, #0
686		mcr	p15, 0, r0, c8, c7, 0	@ flush UTLB
687		mov	pc, r12
688
689__common_mmu_cache_on:
690#ifndef CONFIG_THUMB2_KERNEL
691#ifndef DEBUG
692		orr	r0, r0, #0x000d		@ Write buffer, mmu
693#endif
694		mov	r1, #-1
695		mcr	p15, 0, r3, c2, c0, 0	@ load page table pointer
696		mcr	p15, 0, r1, c3, c0, 0	@ load domain access control
697		b	1f
698		.align	5			@ cache line aligned
6991:		mcr	p15, 0, r0, c1, c0, 0	@ load control register
700		mrc	p15, 0, r0, c1, c0, 0	@ and read it back to
701		sub	pc, lr, r0, lsr #32	@ properly flush pipeline
702#endif
703
704#define PROC_ENTRY_SIZE (4*5)
705
706/*
707 * Here follow the relocatable cache support functions for the
708 * various processors.  This is a generic hook for locating an
709 * entry and jumping to an instruction at the specified offset
710 * from the start of the block.  Please note this is all position
711 * independent code.
712 *
713 *  r1  = corrupted
714 *  r2  = corrupted
715 *  r3  = block offset
716 *  r9  = corrupted
717 *  r12 = corrupted
718 */
719
720call_cache_fn:	adr	r12, proc_types
721#ifdef CONFIG_CPU_CP15
722		mrc	p15, 0, r9, c0, c0	@ get processor ID
723#else
724		ldr	r9, =CONFIG_PROCESSOR_ID
725#endif
7261:		ldr	r1, [r12, #0]		@ get value
727		ldr	r2, [r12, #4]		@ get mask
728		eor	r1, r1, r9		@ (real ^ match)
729		tst	r1, r2			@       & mask
730 ARM(		addeq	pc, r12, r3		) @ call cache function
731 THUMB(		addeq	r12, r3			)
732 THUMB(		moveq	pc, r12			) @ call cache function
733		add	r12, r12, #PROC_ENTRY_SIZE
734		b	1b
735
736/*
737 * Table for cache operations.  This is basically:
738 *   - CPU ID match
739 *   - CPU ID mask
740 *   - 'cache on' method instruction
741 *   - 'cache off' method instruction
742 *   - 'cache flush' method instruction
743 *
744 * We match an entry using: ((real_id ^ match) & mask) == 0
745 *
746 * Writethrough caches generally only need 'on' and 'off'
747 * methods.  Writeback caches _must_ have the flush method
748 * defined.
749 */
750		.align	2
751		.type	proc_types,#object
752proc_types:
753		.word	0x00000000		@ old ARM ID
754		.word	0x0000f000
755		mov	pc, lr
756 THUMB(		nop				)
757		mov	pc, lr
758 THUMB(		nop				)
759		mov	pc, lr
760 THUMB(		nop				)
761
762		.word	0x41007000		@ ARM7/710
763		.word	0xfff8fe00
764		mov	pc, lr
765 THUMB(		nop				)
766		mov	pc, lr
767 THUMB(		nop				)
768		mov	pc, lr
769 THUMB(		nop				)
770
771		.word	0x41807200		@ ARM720T (writethrough)
772		.word	0xffffff00
773		W(b)	__armv4_mmu_cache_on
774		W(b)	__armv4_mmu_cache_off
775		mov	pc, lr
776 THUMB(		nop				)
777
778		.word	0x41007400		@ ARM74x
779		.word	0xff00ff00
780		W(b)	__armv3_mpu_cache_on
781		W(b)	__armv3_mpu_cache_off
782		W(b)	__armv3_mpu_cache_flush
783
784		.word	0x41009400		@ ARM94x
785		.word	0xff00ff00
786		W(b)	__armv4_mpu_cache_on
787		W(b)	__armv4_mpu_cache_off
788		W(b)	__armv4_mpu_cache_flush
789
790		.word	0x41069260		@ ARM926EJ-S (v5TEJ)
791		.word	0xff0ffff0
792		W(b)	__arm926ejs_mmu_cache_on
793		W(b)	__armv4_mmu_cache_off
794		W(b)	__armv5tej_mmu_cache_flush
795
796		.word	0x00007000		@ ARM7 IDs
797		.word	0x0000f000
798		mov	pc, lr
799 THUMB(		nop				)
800		mov	pc, lr
801 THUMB(		nop				)
802		mov	pc, lr
803 THUMB(		nop				)
804
805		@ Everything from here on will be the new ID system.
806
807		.word	0x4401a100		@ sa110 / sa1100
808		.word	0xffffffe0
809		W(b)	__armv4_mmu_cache_on
810		W(b)	__armv4_mmu_cache_off
811		W(b)	__armv4_mmu_cache_flush
812
813		.word	0x6901b110		@ sa1110
814		.word	0xfffffff0
815		W(b)	__armv4_mmu_cache_on
816		W(b)	__armv4_mmu_cache_off
817		W(b)	__armv4_mmu_cache_flush
818
819		.word	0x56056900
820		.word	0xffffff00		@ PXA9xx
821		W(b)	__armv4_mmu_cache_on
822		W(b)	__armv4_mmu_cache_off
823		W(b)	__armv4_mmu_cache_flush
824
825		.word	0x56158000		@ PXA168
826		.word	0xfffff000
827		W(b)	__armv4_mmu_cache_on
828		W(b)	__armv4_mmu_cache_off
829		W(b)	__armv5tej_mmu_cache_flush
830
831		.word	0x56050000		@ Feroceon
832		.word	0xff0f0000
833		W(b)	__armv4_mmu_cache_on
834		W(b)	__armv4_mmu_cache_off
835		W(b)	__armv5tej_mmu_cache_flush
836
837#ifdef CONFIG_CPU_FEROCEON_OLD_ID
838		/* this conflicts with the standard ARMv5TE entry */
839		.long	0x41009260		@ Old Feroceon
840		.long	0xff00fff0
841		b	__armv4_mmu_cache_on
842		b	__armv4_mmu_cache_off
843		b	__armv5tej_mmu_cache_flush
844#endif
845
846		.word	0x66015261		@ FA526
847		.word	0xff01fff1
848		W(b)	__fa526_cache_on
849		W(b)	__armv4_mmu_cache_off
850		W(b)	__fa526_cache_flush
851
852		@ These match on the architecture ID
853
854		.word	0x00020000		@ ARMv4T
855		.word	0x000f0000
856		W(b)	__armv4_mmu_cache_on
857		W(b)	__armv4_mmu_cache_off
858		W(b)	__armv4_mmu_cache_flush
859
860		.word	0x00050000		@ ARMv5TE
861		.word	0x000f0000
862		W(b)	__armv4_mmu_cache_on
863		W(b)	__armv4_mmu_cache_off
864		W(b)	__armv4_mmu_cache_flush
865
866		.word	0x00060000		@ ARMv5TEJ
867		.word	0x000f0000
868		W(b)	__armv4_mmu_cache_on
869		W(b)	__armv4_mmu_cache_off
870		W(b)	__armv5tej_mmu_cache_flush
871
872		.word	0x0007b000		@ ARMv6
873		.word	0x000ff000
874		W(b)	__armv4_mmu_cache_on
875		W(b)	__armv4_mmu_cache_off
876		W(b)	__armv6_mmu_cache_flush
877
878		.word	0x000f0000		@ new CPU Id
879		.word	0x000f0000
880		W(b)	__armv7_mmu_cache_on
881		W(b)	__armv7_mmu_cache_off
882		W(b)	__armv7_mmu_cache_flush
883
884		.word	0			@ unrecognised type
885		.word	0
886		mov	pc, lr
887 THUMB(		nop				)
888		mov	pc, lr
889 THUMB(		nop				)
890		mov	pc, lr
891 THUMB(		nop				)
892
893		.size	proc_types, . - proc_types
894
895		/*
896		 * If you get a "non-constant expression in ".if" statement"
897		 * error from the assembler on this line, check that you have
898		 * not accidentally written a "b" instruction where you should
899		 * have written W(b).
900		 */
901		.if (. - proc_types) % PROC_ENTRY_SIZE != 0
902		.error "The size of one or more proc_types entries is wrong."
903		.endif
904
905/*
906 * Turn off the Cache and MMU.  ARMv3 does not support
907 * reading the control register, but ARMv4 does.
908 *
909 * On exit,
910 *  r0, r1, r2, r3, r9, r12 corrupted
911 * This routine must preserve:
912 *  r4, r7, r8
913 */
914		.align	5
915cache_off:	mov	r3, #12			@ cache_off function
916		b	call_cache_fn
917
918__armv4_mpu_cache_off:
919		mrc	p15, 0, r0, c1, c0
920		bic	r0, r0, #0x000d
921		mcr	p15, 0, r0, c1, c0	@ turn MPU and cache off
922		mov	r0, #0
923		mcr	p15, 0, r0, c7, c10, 4	@ drain write buffer
924		mcr	p15, 0, r0, c7, c6, 0	@ flush D-Cache
925		mcr	p15, 0, r0, c7, c5, 0	@ flush I-Cache
926		mov	pc, lr
927
928__armv3_mpu_cache_off:
929		mrc	p15, 0, r0, c1, c0
930		bic	r0, r0, #0x000d
931		mcr	p15, 0, r0, c1, c0, 0	@ turn MPU and cache off
932		mov	r0, #0
933		mcr	p15, 0, r0, c7, c0, 0	@ invalidate whole cache v3
934		mov	pc, lr
935
936__armv4_mmu_cache_off:
937#ifdef CONFIG_MMU
938		mrc	p15, 0, r0, c1, c0
939		bic	r0, r0, #0x000d
940		mcr	p15, 0, r0, c1, c0	@ turn MMU and cache off
941		mov	r0, #0
942		mcr	p15, 0, r0, c7, c7	@ invalidate whole cache v4
943		mcr	p15, 0, r0, c8, c7	@ invalidate whole TLB v4
944#endif
945		mov	pc, lr
946
947__armv7_mmu_cache_off:
948		mrc	p15, 0, r0, c1, c0
949#ifdef CONFIG_MMU
950		bic	r0, r0, #0x000d
951#else
952		bic	r0, r0, #0x000c
953#endif
954		mcr	p15, 0, r0, c1, c0	@ turn MMU and cache off
955		mov	r12, lr
956		bl	__armv7_mmu_cache_flush
957		mov	r0, #0
958#ifdef CONFIG_MMU
959		mcr	p15, 0, r0, c8, c7, 0	@ invalidate whole TLB
960#endif
961		mcr	p15, 0, r0, c7, c5, 6	@ invalidate BTC
962		mcr	p15, 0, r0, c7, c10, 4	@ DSB
963		mcr	p15, 0, r0, c7, c5, 4	@ ISB
964		mov	pc, r12
965
966/*
967 * Clean and flush the cache to maintain consistency.
968 *
969 * On exit,
970 *  r1, r2, r3, r9, r10, r11, r12 corrupted
971 * This routine must preserve:
972 *  r4, r6, r7, r8
973 */
974		.align	5
975cache_clean_flush:
976		mov	r3, #16
977		b	call_cache_fn
978
979__armv4_mpu_cache_flush:
980		mov	r2, #1
981		mov	r3, #0
982		mcr	p15, 0, ip, c7, c6, 0	@ invalidate D cache
983		mov	r1, #7 << 5		@ 8 segments
9841:		orr	r3, r1, #63 << 26	@ 64 entries
9852:		mcr	p15, 0, r3, c7, c14, 2	@ clean & invalidate D index
986		subs	r3, r3, #1 << 26
987		bcs	2b			@ entries 63 to 0
988		subs 	r1, r1, #1 << 5
989		bcs	1b			@ segments 7 to 0
990
991		teq	r2, #0
992		mcrne	p15, 0, ip, c7, c5, 0	@ invalidate I cache
993		mcr	p15, 0, ip, c7, c10, 4	@ drain WB
994		mov	pc, lr
995
996__fa526_cache_flush:
997		mov	r1, #0
998		mcr	p15, 0, r1, c7, c14, 0	@ clean and invalidate D cache
999		mcr	p15, 0, r1, c7, c5, 0	@ flush I cache
1000		mcr	p15, 0, r1, c7, c10, 4	@ drain WB
1001		mov	pc, lr
1002
1003__armv6_mmu_cache_flush:
1004		mov	r1, #0
1005		mcr	p15, 0, r1, c7, c14, 0	@ clean+invalidate D
1006		mcr	p15, 0, r1, c7, c5, 0	@ invalidate I+BTB
1007		mcr	p15, 0, r1, c7, c15, 0	@ clean+invalidate unified
1008		mcr	p15, 0, r1, c7, c10, 4	@ drain WB
1009		mov	pc, lr
1010
1011__armv7_mmu_cache_flush:
1012		mrc	p15, 0, r10, c0, c1, 5	@ read ID_MMFR1
1013		tst	r10, #0xf << 16		@ hierarchical cache (ARMv7)
1014		mov	r10, #0
1015		beq	hierarchical
1016		mcr	p15, 0, r10, c7, c14, 0	@ clean+invalidate D
1017		b	iflush
1018hierarchical:
1019		mcr	p15, 0, r10, c7, c10, 5	@ DMB
1020		stmfd	sp!, {r0-r7, r9-r11}
1021		mrc	p15, 1, r0, c0, c0, 1	@ read clidr
1022		ands	r3, r0, #0x7000000	@ extract loc from clidr
1023		mov	r3, r3, lsr #23		@ left align loc bit field
1024		beq	finished		@ if loc is 0, then no need to clean
1025		mov	r10, #0			@ start clean at cache level 0
1026loop1:
1027		add	r2, r10, r10, lsr #1	@ work out 3x current cache level
1028		mov	r1, r0, lsr r2		@ extract cache type bits from clidr
1029		and	r1, r1, #7		@ mask of the bits for current cache only
1030		cmp	r1, #2			@ see what cache we have at this level
1031		blt	skip			@ skip if no cache, or just i-cache
1032		mcr	p15, 2, r10, c0, c0, 0	@ select current cache level in cssr
1033		mcr	p15, 0, r10, c7, c5, 4	@ isb to sych the new cssr&csidr
1034		mrc	p15, 1, r1, c0, c0, 0	@ read the new csidr
1035		and	r2, r1, #7		@ extract the length of the cache lines
1036		add	r2, r2, #4		@ add 4 (line length offset)
1037		ldr	r4, =0x3ff
1038		ands	r4, r4, r1, lsr #3	@ find maximum number on the way size
1039		clz	r5, r4			@ find bit position of way size increment
1040		ldr	r7, =0x7fff
1041		ands	r7, r7, r1, lsr #13	@ extract max number of the index size
1042loop2:
1043		mov	r9, r4			@ create working copy of max way size
1044loop3:
1045 ARM(		orr	r11, r10, r9, lsl r5	) @ factor way and cache number into r11
1046 ARM(		orr	r11, r11, r7, lsl r2	) @ factor index number into r11
1047 THUMB(		lsl	r6, r9, r5		)
1048 THUMB(		orr	r11, r10, r6		) @ factor way and cache number into r11
1049 THUMB(		lsl	r6, r7, r2		)
1050 THUMB(		orr	r11, r11, r6		) @ factor index number into r11
1051		mcr	p15, 0, r11, c7, c14, 2	@ clean & invalidate by set/way
1052		subs	r9, r9, #1		@ decrement the way
1053		bge	loop3
1054		subs	r7, r7, #1		@ decrement the index
1055		bge	loop2
1056skip:
1057		add	r10, r10, #2		@ increment cache number
1058		cmp	r3, r10
1059		bgt	loop1
1060finished:
1061		ldmfd	sp!, {r0-r7, r9-r11}
1062		mov	r10, #0			@ swith back to cache level 0
1063		mcr	p15, 2, r10, c0, c0, 0	@ select current cache level in cssr
1064iflush:
1065		mcr	p15, 0, r10, c7, c10, 4	@ DSB
1066		mcr	p15, 0, r10, c7, c5, 0	@ invalidate I+BTB
1067		mcr	p15, 0, r10, c7, c10, 4	@ DSB
1068		mcr	p15, 0, r10, c7, c5, 4	@ ISB
1069		mov	pc, lr
1070
1071__armv5tej_mmu_cache_flush:
10721:		mrc	p15, 0, r15, c7, c14, 3	@ test,clean,invalidate D cache
1073		bne	1b
1074		mcr	p15, 0, r0, c7, c5, 0	@ flush I cache
1075		mcr	p15, 0, r0, c7, c10, 4	@ drain WB
1076		mov	pc, lr
1077
1078__armv4_mmu_cache_flush:
1079		mov	r2, #64*1024		@ default: 32K dcache size (*2)
1080		mov	r11, #32		@ default: 32 byte line size
1081		mrc	p15, 0, r3, c0, c0, 1	@ read cache type
1082		teq	r3, r9			@ cache ID register present?
1083		beq	no_cache_id
1084		mov	r1, r3, lsr #18
1085		and	r1, r1, #7
1086		mov	r2, #1024
1087		mov	r2, r2, lsl r1		@ base dcache size *2
1088		tst	r3, #1 << 14		@ test M bit
1089		addne	r2, r2, r2, lsr #1	@ +1/2 size if M == 1
1090		mov	r3, r3, lsr #12
1091		and	r3, r3, #3
1092		mov	r11, #8
1093		mov	r11, r11, lsl r3	@ cache line size in bytes
1094no_cache_id:
1095		mov	r1, pc
1096		bic	r1, r1, #63		@ align to longest cache line
1097		add	r2, r1, r2
10981:
1099 ARM(		ldr	r3, [r1], r11		) @ s/w flush D cache
1100 THUMB(		ldr     r3, [r1]		) @ s/w flush D cache
1101 THUMB(		add     r1, r1, r11		)
1102		teq	r1, r2
1103		bne	1b
1104
1105		mcr	p15, 0, r1, c7, c5, 0	@ flush I cache
1106		mcr	p15, 0, r1, c7, c6, 0	@ flush D cache
1107		mcr	p15, 0, r1, c7, c10, 4	@ drain WB
1108		mov	pc, lr
1109
1110__armv3_mmu_cache_flush:
1111__armv3_mpu_cache_flush:
1112		mov	r1, #0
1113		mcr	p15, 0, r1, c7, c0, 0	@ invalidate whole cache v3
1114		mov	pc, lr
1115
1116/*
1117 * Various debugging routines for printing hex characters and
1118 * memory, which again must be relocatable.
1119 */
1120#ifdef DEBUG
1121		.align	2
1122		.type	phexbuf,#object
1123phexbuf:	.space	12
1124		.size	phexbuf, . - phexbuf
1125
1126@ phex corrupts {r0, r1, r2, r3}
1127phex:		adr	r3, phexbuf
1128		mov	r2, #0
1129		strb	r2, [r3, r1]
11301:		subs	r1, r1, #1
1131		movmi	r0, r3
1132		bmi	puts
1133		and	r2, r0, #15
1134		mov	r0, r0, lsr #4
1135		cmp	r2, #10
1136		addge	r2, r2, #7
1137		add	r2, r2, #'0'
1138		strb	r2, [r3, r1]
1139		b	1b
1140
1141@ puts corrupts {r0, r1, r2, r3}
1142puts:		loadsp	r3, r1
11431:		ldrb	r2, [r0], #1
1144		teq	r2, #0
1145		moveq	pc, lr
11462:		writeb	r2, r3
1147		mov	r1, #0x00020000
11483:		subs	r1, r1, #1
1149		bne	3b
1150		teq	r2, #'\n'
1151		moveq	r2, #'\r'
1152		beq	2b
1153		teq	r0, #0
1154		bne	1b
1155		mov	pc, lr
1156@ putc corrupts {r0, r1, r2, r3}
1157putc:
1158		mov	r2, r0
1159		mov	r0, #0
1160		loadsp	r3, r1
1161		b	2b
1162
1163@ memdump corrupts {r0, r1, r2, r3, r10, r11, r12, lr}
1164memdump:	mov	r12, r0
1165		mov	r10, lr
1166		mov	r11, #0
11672:		mov	r0, r11, lsl #2
1168		add	r0, r0, r12
1169		mov	r1, #8
1170		bl	phex
1171		mov	r0, #':'
1172		bl	putc
11731:		mov	r0, #' '
1174		bl	putc
1175		ldr	r0, [r12, r11, lsl #2]
1176		mov	r1, #8
1177		bl	phex
1178		and	r0, r11, #7
1179		teq	r0, #3
1180		moveq	r0, #' '
1181		bleq	putc
1182		and	r0, r11, #7
1183		add	r11, r11, #1
1184		teq	r0, #7
1185		bne	1b
1186		mov	r0, #'\n'
1187		bl	putc
1188		cmp	r11, #64
1189		blt	2b
1190		mov	pc, r10
1191#endif
1192
1193		.ltorg
1194reloc_code_end:
1195
1196		.align
1197		.section ".stack", "aw", %nobits
1198.L_user_stack:	.space	4096
1199.L_user_stack_end:
1200