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musb_debugfs.c: remove unneeded includes on ARM
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CommitLineData
1da177e4
LT
1/*
2 * linux/arch/arm/kernel/head.S
3 *
4 * Copyright (C) 1994-2002 Russell King
e65f38ed
RK
5 * Copyright (c) 2003 ARM Limited
6 * All Rights Reserved
1da177e4
LT
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 */
1da177e4
LT
14#include <linux/linkage.h>
15#include <linux/init.h>
16
17#include <asm/assembler.h>
18#include <asm/domain.h>
1da177e4 19#include <asm/ptrace.h>
e6ae744d 20#include <asm/asm-offsets.h>
f09b9979 21#include <asm/memory.h>
4f7a1812 22#include <asm/thread_info.h>
1da177e4
LT
23#include <asm/system.h>
24
c293393f
JK
25#ifdef CONFIG_DEBUG_LL
26#include <mach/debug-macro.S>
27#endif
28
1da177e4 29/*
37d07b72 30 * swapper_pg_dir is the virtual address of the initial page table.
f06b97ff
RK
31 * We place the page tables 16K below KERNEL_RAM_VADDR. Therefore, we must
32 * make sure that KERNEL_RAM_VADDR is correctly set. Currently, we expect
37d07b72 33 * the least significant 16 bits to be 0x8000, but we could probably
f06b97ff 34 * relax this restriction to KERNEL_RAM_VADDR >= PAGE_OFFSET + 0x4000.
1da177e4 35 */
72a20e22 36#define KERNEL_RAM_VADDR (PAGE_OFFSET + TEXT_OFFSET)
f06b97ff
RK
37#if (KERNEL_RAM_VADDR & 0xffff) != 0x8000
38#error KERNEL_RAM_VADDR must start at 0xXXXX8000
1da177e4
LT
39#endif
40
41 .globl swapper_pg_dir
f06b97ff 42 .equ swapper_pg_dir, KERNEL_RAM_VADDR - 0x4000
1da177e4 43
72a20e22
RK
44 .macro pgtbl, rd, phys
45 add \rd, \phys, #TEXT_OFFSET - 0x4000
1da177e4 46 .endm
1da177e4 47
37d07b72 48#ifdef CONFIG_XIP_KERNEL
e98ff7f6
NP
49#define KERNEL_START XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR)
50#define KERNEL_END _edata_loc
37d07b72 51#else
e98ff7f6
NP
52#define KERNEL_START KERNEL_RAM_VADDR
53#define KERNEL_END _end
1da177e4
LT
54#endif
55
56/*
57 * Kernel startup entry point.
58 * ---------------------------
59 *
60 * This is normally called from the decompressor code. The requirements
61 * are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
4c2896e8 62 * r1 = machine nr, r2 = atags or dtb pointer.
1da177e4
LT
63 *
64 * This code is mostly position independent, so if you link the kernel at
65 * 0xc0008000, you call this at __pa(0xc0008000).
66 *
67 * See linux/arch/arm/tools/mach-types for the complete list of machine
68 * numbers for r1.
69 *
70 * We're trying to keep crap to a minimum; DO NOT add any machine specific
71 * crap here - that's what the boot loader (or in extreme, well justified
72 * circumstances, zImage) is for.
73 */
540b5738
DM
74 .arm
75
2abc1c50 76 __HEAD
1da177e4 77ENTRY(stext)
540b5738
DM
78
79 THUMB( adr r9, BSYM(1f) ) @ Kernel is always entered in ARM.
80 THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
81 THUMB( .thumb ) @ switch to Thumb now.
82 THUMB(1: )
83
b86040a5 84 setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
1da177e4 85 @ and irqs disabled
0f44ba1d 86 mrc p15, 0, r9, c0, c0 @ get processor id
1da177e4
LT
87 bl __lookup_processor_type @ r5=procinfo r9=cpuid
88 movs r10, r5 @ invalid processor (r5=0)?
a75e5248 89 THUMB( it eq ) @ force fixup-able long branch encoding
3c0bdac3 90 beq __error_p @ yes, error 'p'
0eb0511d 91
72a20e22
RK
92#ifndef CONFIG_XIP_KERNEL
93 adr r3, 2f
94 ldmia r3, {r4, r8}
95 sub r4, r3, r4 @ (PHYS_OFFSET - PAGE_OFFSET)
96 add r8, r8, r4 @ PHYS_OFFSET
97#else
98 ldr r8, =PLAT_PHYS_OFFSET
99#endif
100
0eb0511d 101 /*
4c2896e8 102 * r1 = machine no, r2 = atags or dtb,
72a20e22 103 * r8 = phys_offset, r9 = cpuid, r10 = procinfo
0eb0511d 104 */
9d20fdd5 105 bl __vet_atags
f00ec48f
RK
106#ifdef CONFIG_SMP_ON_UP
107 bl __fixup_smp
dc21af99
RK
108#endif
109#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
110 bl __fixup_pv_table
f00ec48f 111#endif
1da177e4
LT
112 bl __create_page_tables
113
114 /*
115 * The following calls CPU specific code in a position independent
116 * manner. See arch/arm/mm/proc-*.S for details. r10 = base of
6fc31d54 117 * xxx_proc_info structure selected by __lookup_processor_type
1da177e4
LT
118 * above. On return, the CPU will be ready for the MMU to be
119 * turned on, and r0 will hold the CPU control register value.
120 */
a4ae4134 121 ldr r13, =__mmap_switched @ address to jump to after
1da177e4 122 @ mmu has been enabled
00945010 123 adr lr, BSYM(1f) @ return (PIC) address
d427958a 124 mov r8, r4 @ set TTBR1 to swapper_pg_dir
b86040a5
CM
125 ARM( add pc, r10, #PROCINFO_INITFUNC )
126 THUMB( add r12, r10, #PROCINFO_INITFUNC )
127 THUMB( mov pc, r12 )
00945010 1281: b __enable_mmu
93ed3970 129ENDPROC(stext)
a4ae4134 130 .ltorg
72a20e22
RK
131#ifndef CONFIG_XIP_KERNEL
1322: .long .
133 .long PAGE_OFFSET
134#endif
1da177e4
LT
135
136/*
137 * Setup the initial page tables. We only setup the barest
138 * amount which are required to get the kernel running, which
139 * generally means mapping in the kernel code.
140 *
72a20e22 141 * r8 = phys_offset, r9 = cpuid, r10 = procinfo
1da177e4
LT
142 *
143 * Returns:
786f1b73 144 * r0, r3, r5-r7 corrupted
1da177e4
LT
145 * r4 = physical page table address
146 */
1da177e4 147__create_page_tables:
72a20e22 148 pgtbl r4, r8 @ page table address
1da177e4
LT
149
150 /*
151 * Clear the 16K level 1 swapper page table
152 */
153 mov r0, r4
154 mov r3, #0
155 add r6, r0, #0x4000
1561: str r3, [r0], #4
157 str r3, [r0], #4
158 str r3, [r0], #4
159 str r3, [r0], #4
160 teq r0, r6
161 bne 1b
162
8799ee9f 163 ldr r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags
1da177e4
LT
164
165 /*
786f1b73
RK
166 * Create identity mapping to cater for __enable_mmu.
167 * This identity mapping will be removed by paging_init().
1da177e4 168 */
786f1b73
RK
169 adr r0, __enable_mmu_loc
170 ldmia r0, {r3, r5, r6}
171 sub r0, r0, r3 @ virt->phys offset
172 add r5, r5, r0 @ phys __enable_mmu
173 add r6, r6, r0 @ phys __enable_mmu_end
174 mov r5, r5, lsr #20
175 mov r6, r6, lsr #20
176
1771: orr r3, r7, r5, lsl #20 @ flags + kernel base
178 str r3, [r4, r5, lsl #2] @ identity mapping
179 teq r5, r6
180 addne r5, r5, #1 @ next section
181 bne 1b
1da177e4
LT
182
183 /*
184 * Now setup the pagetables for our kernel direct
2552fc27 185 * mapped region.
1da177e4 186 */
786f1b73
RK
187 mov r3, pc
188 mov r3, r3, lsr #20
189 orr r3, r7, r3, lsl #20
e98ff7f6
NP
190 add r0, r4, #(KERNEL_START & 0xff000000) >> 18
191 str r3, [r0, #(KERNEL_START & 0x00f00000) >> 18]!
192 ldr r6, =(KERNEL_END - 1)
193 add r0, r0, #4
194 add r6, r4, r6, lsr #18
1951: cmp r0, r6
196 add r3, r3, #1 << 20
197 strls r3, [r0], #4
198 bls 1b
1da177e4 199
ec3622d9
NP
200#ifdef CONFIG_XIP_KERNEL
201 /*
202 * Map some ram to cover our .data and .bss areas.
203 */
72a20e22
RK
204 add r3, r8, #TEXT_OFFSET
205 orr r3, r3, r7
ec3622d9
NP
206 add r0, r4, #(KERNEL_RAM_VADDR & 0xff000000) >> 18
207 str r3, [r0, #(KERNEL_RAM_VADDR & 0x00f00000) >> 18]!
208 ldr r6, =(_end - 1)
209 add r0, r0, #4
210 add r6, r4, r6, lsr #18
2111: cmp r0, r6
212 add r3, r3, #1 << 20
213 strls r3, [r0], #4
214 bls 1b
215#endif
216
1da177e4 217 /*
4d901c42
RH
218 * Then map boot params address in r2 or
219 * the first 1MB of ram if boot params address is not specified.
1da177e4 220 */
4d901c42
RH
221 mov r0, r2, lsr #20
222 movs r0, r0, lsl #20
223 moveq r0, r8
224 sub r3, r0, r8
225 add r3, r3, #PAGE_OFFSET
226 add r3, r4, r3, lsr #18
227 orr r6, r7, r0
228 str r6, [r3]
1da177e4 229
c77b0427 230#ifdef CONFIG_DEBUG_LL
c293393f 231#ifndef CONFIG_DEBUG_ICEDCC
1da177e4
LT
232 /*
233 * Map in IO space for serial debugging.
234 * This allows debug messages to be output
235 * via a serial console before paging_init.
236 */
c293393f
JK
237 addruart r7, r3
238
239 mov r3, r3, lsr #20
240 mov r3, r3, lsl #2
241
1da177e4
LT
242 add r0, r4, r3
243 rsb r3, r3, #0x4000 @ PTRS_PER_PGD*sizeof(long)
244 cmp r3, #0x0800 @ limit to 512MB
245 movhi r3, #0x0800
246 add r6, r0, r3
c293393f
JK
247 mov r3, r7, lsr #20
248 ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
249 orr r3, r7, r3, lsl #20
1da177e4
LT
2501: str r3, [r0], #4
251 add r3, r3, #1 << 20
252 teq r0, r6
253 bne 1b
c293393f
JK
254
255#else /* CONFIG_DEBUG_ICEDCC */
256 /* we don't need any serial debugging mappings for ICEDCC */
257 ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags
258#endif /* !CONFIG_DEBUG_ICEDCC */
259
1da177e4
LT
260#if defined(CONFIG_ARCH_NETWINDER) || defined(CONFIG_ARCH_CATS)
261 /*
3c0bdac3
RK
262 * If we're using the NetWinder or CATS, we also need to map
263 * in the 16550-type serial port for the debug messages
1da177e4 264 */
c77b0427
RK
265 add r0, r4, #0xff000000 >> 18
266 orr r3, r7, #0x7c000000
267 str r3, [r0]
1da177e4 268#endif
1da177e4
LT
269#ifdef CONFIG_ARCH_RPC
270 /*
271 * Map in screen at 0x02000000 & SCREEN2_BASE
272 * Similar reasons here - for debug. This is
273 * only for Acorn RiscPC architectures.
274 */
c77b0427
RK
275 add r0, r4, #0x02000000 >> 18
276 orr r3, r7, #0x02000000
1da177e4 277 str r3, [r0]
c77b0427 278 add r0, r4, #0xd8000000 >> 18
1da177e4 279 str r3, [r0]
c77b0427 280#endif
1da177e4
LT
281#endif
282 mov pc, lr
93ed3970 283ENDPROC(__create_page_tables)
1da177e4 284 .ltorg
4f79a5dd 285 .align
786f1b73
RK
286__enable_mmu_loc:
287 .long .
288 .long __enable_mmu
289 .long __enable_mmu_end
1da177e4 290
00945010
RK
291#if defined(CONFIG_SMP)
292 __CPUINIT
293ENTRY(secondary_startup)
294 /*
295 * Common entry point for secondary CPUs.
296 *
297 * Ensure that we're in SVC mode, and IRQs are disabled. Lookup
298 * the processor type - there is no need to check the machine type
299 * as it has already been validated by the primary processor.
300 */
301 setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9
302 mrc p15, 0, r9, c0, c0 @ get processor id
303 bl __lookup_processor_type
304 movs r10, r5 @ invalid processor?
305 moveq r0, #'p' @ yes, error 'p'
a75e5248 306 THUMB( it eq ) @ force fixup-able long branch encoding
00945010
RK
307 beq __error_p
308
309 /*
310 * Use the page tables supplied from __cpu_up.
311 */
312 adr r4, __secondary_data
313 ldmia r4, {r5, r7, r12} @ address to jump to after
d427958a
CM
314 sub lr, r4, r5 @ mmu has been enabled
315 ldr r4, [r7, lr] @ get secondary_data.pgdir
316 add r7, r7, #4
317 ldr r8, [r7, lr] @ get secondary_data.swapper_pg_dir
00945010
RK
318 adr lr, BSYM(__enable_mmu) @ return address
319 mov r13, r12 @ __secondary_switched address
320 ARM( add pc, r10, #PROCINFO_INITFUNC ) @ initialise processor
321 @ (return control reg)
322 THUMB( add r12, r10, #PROCINFO_INITFUNC )
323 THUMB( mov pc, r12 )
324ENDPROC(secondary_startup)
325
326 /*
327 * r6 = &secondary_data
328 */
329ENTRY(__secondary_switched)
330 ldr sp, [r7, #4] @ get secondary_data.stack
331 mov fp, #0
332 b secondary_start_kernel
333ENDPROC(__secondary_switched)
334
4f79a5dd
DM
335 .align
336
00945010
RK
337 .type __secondary_data, %object
338__secondary_data:
339 .long .
340 .long secondary_data
341 .long __secondary_switched
342#endif /* defined(CONFIG_SMP) */
343
344
345
346/*
347 * Setup common bits before finally enabling the MMU. Essentially
348 * this is just loading the page table pointer and domain access
349 * registers.
865a4fae
RK
350 *
351 * r0 = cp#15 control register
352 * r1 = machine ID
4c2896e8 353 * r2 = atags or dtb pointer
865a4fae
RK
354 * r4 = page table pointer
355 * r9 = processor ID
356 * r13 = *virtual* address to jump to upon completion
00945010
RK
357 */
358__enable_mmu:
359#ifdef CONFIG_ALIGNMENT_TRAP
360 orr r0, r0, #CR_A
361#else
362 bic r0, r0, #CR_A
363#endif
364#ifdef CONFIG_CPU_DCACHE_DISABLE
365 bic r0, r0, #CR_C
366#endif
367#ifdef CONFIG_CPU_BPREDICT_DISABLE
368 bic r0, r0, #CR_Z
369#endif
370#ifdef CONFIG_CPU_ICACHE_DISABLE
371 bic r0, r0, #CR_I
372#endif
373 mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \
374 domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \
375 domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \
376 domain_val(DOMAIN_IO, DOMAIN_CLIENT))
377 mcr p15, 0, r5, c3, c0, 0 @ load domain access register
378 mcr p15, 0, r4, c2, c0, 0 @ load page table pointer
379 b __turn_mmu_on
380ENDPROC(__enable_mmu)
381
382/*
383 * Enable the MMU. This completely changes the structure of the visible
384 * memory space. You will not be able to trace execution through this.
385 * If you have an enquiry about this, *please* check the linux-arm-kernel
386 * mailing list archives BEFORE sending another post to the list.
387 *
388 * r0 = cp#15 control register
865a4fae 389 * r1 = machine ID
4c2896e8 390 * r2 = atags or dtb pointer
865a4fae 391 * r9 = processor ID
00945010
RK
392 * r13 = *virtual* address to jump to upon completion
393 *
394 * other registers depend on the function called upon completion
395 */
396 .align 5
397__turn_mmu_on:
398 mov r0, r0
399 mcr p15, 0, r0, c1, c0, 0 @ write control reg
400 mrc p15, 0, r3, c0, c0, 0 @ read id reg
401 mov r3, r3
402 mov r3, r13
403 mov pc, r3
404__enable_mmu_end:
405ENDPROC(__turn_mmu_on)
406
1da177e4 407
f00ec48f 408#ifdef CONFIG_SMP_ON_UP
4a9cb360 409 __INIT
f00ec48f 410__fixup_smp:
e98ff0f5
RK
411 and r3, r9, #0x000f0000 @ architecture version
412 teq r3, #0x000f0000 @ CPU ID supported?
f00ec48f
RK
413 bne __fixup_smp_on_up @ no, assume UP
414
e98ff0f5
RK
415 bic r3, r9, #0x00ff0000
416 bic r3, r3, #0x0000000f @ mask 0xff00fff0
417 mov r4, #0x41000000
0eb0511d 418 orr r4, r4, #0x0000b000
e98ff0f5
RK
419 orr r4, r4, #0x00000020 @ val 0x4100b020
420 teq r3, r4 @ ARM 11MPCore?
f00ec48f
RK
421 moveq pc, lr @ yes, assume SMP
422
423 mrc p15, 0, r0, c0, c0, 5 @ read MPIDR
e98ff0f5
RK
424 and r0, r0, #0xc0000000 @ multiprocessing extensions and
425 teq r0, #0x80000000 @ not part of a uniprocessor system?
426 moveq pc, lr @ yes, assume SMP
f00ec48f
RK
427
428__fixup_smp_on_up:
429 adr r0, 1f
0eb0511d 430 ldmia r0, {r3 - r5}
f00ec48f 431 sub r3, r0, r3
0eb0511d
RK
432 add r4, r4, r3
433 add r5, r5, r3
4a9cb360 434 b __do_fixup_smp_on_up
f00ec48f
RK
435ENDPROC(__fixup_smp)
436
4f79a5dd 437 .align
f00ec48f
RK
4381: .word .
439 .word __smpalt_begin
440 .word __smpalt_end
441
442 .pushsection .data
443 .globl smp_on_up
444smp_on_up:
445 ALT_SMP(.long 1)
446 ALT_UP(.long 0)
447 .popsection
4a9cb360 448#endif
f00ec48f 449
4a9cb360
RK
450 .text
451__do_fixup_smp_on_up:
452 cmp r4, r5
453 movhs pc, lr
454 ldmia r4!, {r0, r6}
455 ARM( str r6, [r0, r3] )
456 THUMB( add r0, r0, r3 )
457#ifdef __ARMEB__
458 THUMB( mov r6, r6, ror #16 ) @ Convert word order for big-endian.
f00ec48f 459#endif
4a9cb360
RK
460 THUMB( strh r6, [r0], #2 ) @ For Thumb-2, store as two halfwords
461 THUMB( mov r6, r6, lsr #16 ) @ to be robust against misaligned r3.
462 THUMB( strh r6, [r0] )
463 b __do_fixup_smp_on_up
464ENDPROC(__do_fixup_smp_on_up)
465
466ENTRY(fixup_smp)
467 stmfd sp!, {r4 - r6, lr}
468 mov r4, r0
469 add r5, r0, r1
470 mov r3, #0
471 bl __do_fixup_smp_on_up
472 ldmfd sp!, {r4 - r6, pc}
473ENDPROC(fixup_smp)
f00ec48f 474
dc21af99
RK
475#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
476
477/* __fixup_pv_table - patch the stub instructions with the delta between
478 * PHYS_OFFSET and PAGE_OFFSET, which is assumed to be 16MiB aligned and
479 * can be expressed by an immediate shifter operand. The stub instruction
480 * has a form of '(add|sub) rd, rn, #imm'.
481 */
482 __HEAD
483__fixup_pv_table:
484 adr r0, 1f
485 ldmia r0, {r3-r5, r7}
486 sub r3, r0, r3 @ PHYS_OFFSET - PAGE_OFFSET
487 add r4, r4, r3 @ adjust table start address
488 add r5, r5, r3 @ adjust table end address
b511d75d
NP
489 add r7, r7, r3 @ adjust __pv_phys_offset address
490 str r8, [r7] @ save computed PHYS_OFFSET to __pv_phys_offset
dc21af99
RK
491 mov r6, r3, lsr #24 @ constant for add/sub instructions
492 teq r3, r6, lsl #24 @ must be 16MiB aligned
b511d75d 493THUMB( it ne @ cross section branch )
dc21af99
RK
494 bne __error
495 str r6, [r7, #4] @ save to __pv_offset
496 b __fixup_a_pv_table
497ENDPROC(__fixup_pv_table)
498
499 .align
5001: .long .
501 .long __pv_table_begin
502 .long __pv_table_end
5032: .long __pv_phys_offset
504
505 .text
506__fixup_a_pv_table:
b511d75d 507#ifdef CONFIG_THUMB2_KERNEL
daece596
NP
508 lsls r6, #24
509 beq 2f
b511d75d
NP
510 clz r7, r6
511 lsr r6, #24
512 lsl r6, r7
513 bic r6, #0x0080
514 lsrs r7, #1
515 orrcs r6, #0x0080
516 orr r6, r6, r7, lsl #12
517 orr r6, #0x4000
daece596
NP
518 b 2f
5191: add r7, r3
520 ldrh ip, [r7, #2]
b511d75d 521 and ip, 0x8f00
daece596 522 orr ip, r6 @ mask in offset bits 31-24
b511d75d 523 strh ip, [r7, #2]
daece596 5242: cmp r4, r5
b511d75d 525 ldrcc r7, [r4], #4 @ use branch for delay slot
daece596 526 bcc 1b
b511d75d
NP
527 bx lr
528#else
daece596
NP
529 b 2f
5301: ldr ip, [r7, r3]
dc21af99 531 bic ip, ip, #0x000000ff
daece596 532 orr ip, ip, r6 @ mask in offset bits 31-24
dc21af99 533 str ip, [r7, r3]
daece596 5342: cmp r4, r5
dc21af99 535 ldrcc r7, [r4], #4 @ use branch for delay slot
daece596 536 bcc 1b
dc21af99 537 mov pc, lr
b511d75d 538#endif
dc21af99
RK
539ENDPROC(__fixup_a_pv_table)
540
541ENTRY(fixup_pv_table)
542 stmfd sp!, {r4 - r7, lr}
543 ldr r2, 2f @ get address of __pv_phys_offset
544 mov r3, #0 @ no offset
545 mov r4, r0 @ r0 = table start
546 add r5, r0, r1 @ r1 = table size
547 ldr r6, [r2, #4] @ get __pv_offset
548 bl __fixup_a_pv_table
549 ldmfd sp!, {r4 - r7, pc}
550ENDPROC(fixup_pv_table)
551
552 .align
5532: .long __pv_phys_offset
554
555 .data
556 .globl __pv_phys_offset
557 .type __pv_phys_offset, %object
558__pv_phys_offset:
559 .long 0
560 .size __pv_phys_offset, . - __pv_phys_offset
561__pv_offset:
562 .long 0
563#endif
564
75d90832 565#include "head-common.S"