Commit | Line | Data |
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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 | */ | |
2abc1c50 | 74 | __HEAD |
1da177e4 | 75 | ENTRY(stext) |
b86040a5 | 76 | setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode |
1da177e4 | 77 | @ and irqs disabled |
0f44ba1d | 78 | mrc p15, 0, r9, c0, c0 @ get processor id |
1da177e4 LT |
79 | bl __lookup_processor_type @ r5=procinfo r9=cpuid |
80 | movs r10, r5 @ invalid processor (r5=0)? | |
a75e5248 | 81 | THUMB( it eq ) @ force fixup-able long branch encoding |
3c0bdac3 | 82 | beq __error_p @ yes, error 'p' |
0eb0511d | 83 | |
72a20e22 RK |
84 | #ifndef CONFIG_XIP_KERNEL |
85 | adr r3, 2f | |
86 | ldmia r3, {r4, r8} | |
87 | sub r4, r3, r4 @ (PHYS_OFFSET - PAGE_OFFSET) | |
88 | add r8, r8, r4 @ PHYS_OFFSET | |
89 | #else | |
90 | ldr r8, =PLAT_PHYS_OFFSET | |
91 | #endif | |
92 | ||
0eb0511d | 93 | /* |
4c2896e8 | 94 | * r1 = machine no, r2 = atags or dtb, |
72a20e22 | 95 | * r8 = phys_offset, r9 = cpuid, r10 = procinfo |
0eb0511d | 96 | */ |
9d20fdd5 | 97 | bl __vet_atags |
f00ec48f RK |
98 | #ifdef CONFIG_SMP_ON_UP |
99 | bl __fixup_smp | |
dc21af99 RK |
100 | #endif |
101 | #ifdef CONFIG_ARM_PATCH_PHYS_VIRT | |
102 | bl __fixup_pv_table | |
f00ec48f | 103 | #endif |
1da177e4 LT |
104 | bl __create_page_tables |
105 | ||
106 | /* | |
107 | * The following calls CPU specific code in a position independent | |
108 | * manner. See arch/arm/mm/proc-*.S for details. r10 = base of | |
6fc31d54 | 109 | * xxx_proc_info structure selected by __lookup_processor_type |
1da177e4 LT |
110 | * above. On return, the CPU will be ready for the MMU to be |
111 | * turned on, and r0 will hold the CPU control register value. | |
112 | */ | |
a4ae4134 | 113 | ldr r13, =__mmap_switched @ address to jump to after |
1da177e4 | 114 | @ mmu has been enabled |
00945010 | 115 | adr lr, BSYM(1f) @ return (PIC) address |
d427958a | 116 | mov r8, r4 @ set TTBR1 to swapper_pg_dir |
b86040a5 CM |
117 | ARM( add pc, r10, #PROCINFO_INITFUNC ) |
118 | THUMB( add r12, r10, #PROCINFO_INITFUNC ) | |
119 | THUMB( mov pc, r12 ) | |
00945010 | 120 | 1: b __enable_mmu |
93ed3970 | 121 | ENDPROC(stext) |
a4ae4134 | 122 | .ltorg |
72a20e22 RK |
123 | #ifndef CONFIG_XIP_KERNEL |
124 | 2: .long . | |
125 | .long PAGE_OFFSET | |
126 | #endif | |
1da177e4 LT |
127 | |
128 | /* | |
129 | * Setup the initial page tables. We only setup the barest | |
130 | * amount which are required to get the kernel running, which | |
131 | * generally means mapping in the kernel code. | |
132 | * | |
72a20e22 | 133 | * r8 = phys_offset, r9 = cpuid, r10 = procinfo |
1da177e4 LT |
134 | * |
135 | * Returns: | |
786f1b73 | 136 | * r0, r3, r5-r7 corrupted |
1da177e4 LT |
137 | * r4 = physical page table address |
138 | */ | |
1da177e4 | 139 | __create_page_tables: |
72a20e22 | 140 | pgtbl r4, r8 @ page table address |
1da177e4 LT |
141 | |
142 | /* | |
143 | * Clear the 16K level 1 swapper page table | |
144 | */ | |
145 | mov r0, r4 | |
146 | mov r3, #0 | |
147 | add r6, r0, #0x4000 | |
148 | 1: str r3, [r0], #4 | |
149 | str r3, [r0], #4 | |
150 | str r3, [r0], #4 | |
151 | str r3, [r0], #4 | |
152 | teq r0, r6 | |
153 | bne 1b | |
154 | ||
8799ee9f | 155 | ldr r7, [r10, #PROCINFO_MM_MMUFLAGS] @ mm_mmuflags |
1da177e4 LT |
156 | |
157 | /* | |
786f1b73 RK |
158 | * Create identity mapping to cater for __enable_mmu. |
159 | * This identity mapping will be removed by paging_init(). | |
1da177e4 | 160 | */ |
786f1b73 RK |
161 | adr r0, __enable_mmu_loc |
162 | ldmia r0, {r3, r5, r6} | |
163 | sub r0, r0, r3 @ virt->phys offset | |
164 | add r5, r5, r0 @ phys __enable_mmu | |
165 | add r6, r6, r0 @ phys __enable_mmu_end | |
166 | mov r5, r5, lsr #20 | |
167 | mov r6, r6, lsr #20 | |
168 | ||
169 | 1: orr r3, r7, r5, lsl #20 @ flags + kernel base | |
170 | str r3, [r4, r5, lsl #2] @ identity mapping | |
171 | teq r5, r6 | |
172 | addne r5, r5, #1 @ next section | |
173 | bne 1b | |
1da177e4 LT |
174 | |
175 | /* | |
176 | * Now setup the pagetables for our kernel direct | |
2552fc27 | 177 | * mapped region. |
1da177e4 | 178 | */ |
786f1b73 RK |
179 | mov r3, pc |
180 | mov r3, r3, lsr #20 | |
181 | orr r3, r7, r3, lsl #20 | |
e98ff7f6 NP |
182 | add r0, r4, #(KERNEL_START & 0xff000000) >> 18 |
183 | str r3, [r0, #(KERNEL_START & 0x00f00000) >> 18]! | |
184 | ldr r6, =(KERNEL_END - 1) | |
185 | add r0, r0, #4 | |
186 | add r6, r4, r6, lsr #18 | |
187 | 1: cmp r0, r6 | |
188 | add r3, r3, #1 << 20 | |
189 | strls r3, [r0], #4 | |
190 | bls 1b | |
1da177e4 | 191 | |
ec3622d9 NP |
192 | #ifdef CONFIG_XIP_KERNEL |
193 | /* | |
194 | * Map some ram to cover our .data and .bss areas. | |
195 | */ | |
72a20e22 RK |
196 | add r3, r8, #TEXT_OFFSET |
197 | orr r3, r3, r7 | |
ec3622d9 NP |
198 | add r0, r4, #(KERNEL_RAM_VADDR & 0xff000000) >> 18 |
199 | str r3, [r0, #(KERNEL_RAM_VADDR & 0x00f00000) >> 18]! | |
200 | ldr r6, =(_end - 1) | |
201 | add r0, r0, #4 | |
202 | add r6, r4, r6, lsr #18 | |
203 | 1: cmp r0, r6 | |
204 | add r3, r3, #1 << 20 | |
205 | strls r3, [r0], #4 | |
206 | bls 1b | |
207 | #endif | |
208 | ||
1da177e4 | 209 | /* |
4d901c42 RH |
210 | * Then map boot params address in r2 or |
211 | * the first 1MB of ram if boot params address is not specified. | |
1da177e4 | 212 | */ |
4d901c42 RH |
213 | mov r0, r2, lsr #20 |
214 | movs r0, r0, lsl #20 | |
215 | moveq r0, r8 | |
216 | sub r3, r0, r8 | |
217 | add r3, r3, #PAGE_OFFSET | |
218 | add r3, r4, r3, lsr #18 | |
219 | orr r6, r7, r0 | |
220 | str r6, [r3] | |
1da177e4 | 221 | |
c77b0427 | 222 | #ifdef CONFIG_DEBUG_LL |
c293393f | 223 | #ifndef CONFIG_DEBUG_ICEDCC |
1da177e4 LT |
224 | /* |
225 | * Map in IO space for serial debugging. | |
226 | * This allows debug messages to be output | |
227 | * via a serial console before paging_init. | |
228 | */ | |
c293393f JK |
229 | addruart r7, r3 |
230 | ||
231 | mov r3, r3, lsr #20 | |
232 | mov r3, r3, lsl #2 | |
233 | ||
1da177e4 LT |
234 | add r0, r4, r3 |
235 | rsb r3, r3, #0x4000 @ PTRS_PER_PGD*sizeof(long) | |
236 | cmp r3, #0x0800 @ limit to 512MB | |
237 | movhi r3, #0x0800 | |
238 | add r6, r0, r3 | |
c293393f JK |
239 | mov r3, r7, lsr #20 |
240 | ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags | |
241 | orr r3, r7, r3, lsl #20 | |
1da177e4 LT |
242 | 1: str r3, [r0], #4 |
243 | add r3, r3, #1 << 20 | |
244 | teq r0, r6 | |
245 | bne 1b | |
c293393f JK |
246 | |
247 | #else /* CONFIG_DEBUG_ICEDCC */ | |
248 | /* we don't need any serial debugging mappings for ICEDCC */ | |
249 | ldr r7, [r10, #PROCINFO_IO_MMUFLAGS] @ io_mmuflags | |
250 | #endif /* !CONFIG_DEBUG_ICEDCC */ | |
251 | ||
1da177e4 LT |
252 | #if defined(CONFIG_ARCH_NETWINDER) || defined(CONFIG_ARCH_CATS) |
253 | /* | |
3c0bdac3 RK |
254 | * If we're using the NetWinder or CATS, we also need to map |
255 | * in the 16550-type serial port for the debug messages | |
1da177e4 | 256 | */ |
c77b0427 RK |
257 | add r0, r4, #0xff000000 >> 18 |
258 | orr r3, r7, #0x7c000000 | |
259 | str r3, [r0] | |
1da177e4 | 260 | #endif |
1da177e4 LT |
261 | #ifdef CONFIG_ARCH_RPC |
262 | /* | |
263 | * Map in screen at 0x02000000 & SCREEN2_BASE | |
264 | * Similar reasons here - for debug. This is | |
265 | * only for Acorn RiscPC architectures. | |
266 | */ | |
c77b0427 RK |
267 | add r0, r4, #0x02000000 >> 18 |
268 | orr r3, r7, #0x02000000 | |
1da177e4 | 269 | str r3, [r0] |
c77b0427 | 270 | add r0, r4, #0xd8000000 >> 18 |
1da177e4 | 271 | str r3, [r0] |
c77b0427 | 272 | #endif |
1da177e4 LT |
273 | #endif |
274 | mov pc, lr | |
93ed3970 | 275 | ENDPROC(__create_page_tables) |
1da177e4 | 276 | .ltorg |
4f79a5dd | 277 | .align |
786f1b73 RK |
278 | __enable_mmu_loc: |
279 | .long . | |
280 | .long __enable_mmu | |
281 | .long __enable_mmu_end | |
1da177e4 | 282 | |
00945010 RK |
283 | #if defined(CONFIG_SMP) |
284 | __CPUINIT | |
285 | ENTRY(secondary_startup) | |
286 | /* | |
287 | * Common entry point for secondary CPUs. | |
288 | * | |
289 | * Ensure that we're in SVC mode, and IRQs are disabled. Lookup | |
290 | * the processor type - there is no need to check the machine type | |
291 | * as it has already been validated by the primary processor. | |
292 | */ | |
293 | setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 | |
294 | mrc p15, 0, r9, c0, c0 @ get processor id | |
295 | bl __lookup_processor_type | |
296 | movs r10, r5 @ invalid processor? | |
297 | moveq r0, #'p' @ yes, error 'p' | |
a75e5248 | 298 | THUMB( it eq ) @ force fixup-able long branch encoding |
00945010 RK |
299 | beq __error_p |
300 | ||
301 | /* | |
302 | * Use the page tables supplied from __cpu_up. | |
303 | */ | |
304 | adr r4, __secondary_data | |
305 | ldmia r4, {r5, r7, r12} @ address to jump to after | |
d427958a CM |
306 | sub lr, r4, r5 @ mmu has been enabled |
307 | ldr r4, [r7, lr] @ get secondary_data.pgdir | |
308 | add r7, r7, #4 | |
309 | ldr r8, [r7, lr] @ get secondary_data.swapper_pg_dir | |
00945010 RK |
310 | adr lr, BSYM(__enable_mmu) @ return address |
311 | mov r13, r12 @ __secondary_switched address | |
312 | ARM( add pc, r10, #PROCINFO_INITFUNC ) @ initialise processor | |
313 | @ (return control reg) | |
314 | THUMB( add r12, r10, #PROCINFO_INITFUNC ) | |
315 | THUMB( mov pc, r12 ) | |
316 | ENDPROC(secondary_startup) | |
317 | ||
318 | /* | |
319 | * r6 = &secondary_data | |
320 | */ | |
321 | ENTRY(__secondary_switched) | |
322 | ldr sp, [r7, #4] @ get secondary_data.stack | |
323 | mov fp, #0 | |
324 | b secondary_start_kernel | |
325 | ENDPROC(__secondary_switched) | |
326 | ||
4f79a5dd DM |
327 | .align |
328 | ||
00945010 RK |
329 | .type __secondary_data, %object |
330 | __secondary_data: | |
331 | .long . | |
332 | .long secondary_data | |
333 | .long __secondary_switched | |
334 | #endif /* defined(CONFIG_SMP) */ | |
335 | ||
336 | ||
337 | ||
338 | /* | |
339 | * Setup common bits before finally enabling the MMU. Essentially | |
340 | * this is just loading the page table pointer and domain access | |
341 | * registers. | |
865a4fae RK |
342 | * |
343 | * r0 = cp#15 control register | |
344 | * r1 = machine ID | |
4c2896e8 | 345 | * r2 = atags or dtb pointer |
865a4fae RK |
346 | * r4 = page table pointer |
347 | * r9 = processor ID | |
348 | * r13 = *virtual* address to jump to upon completion | |
00945010 RK |
349 | */ |
350 | __enable_mmu: | |
351 | #ifdef CONFIG_ALIGNMENT_TRAP | |
352 | orr r0, r0, #CR_A | |
353 | #else | |
354 | bic r0, r0, #CR_A | |
355 | #endif | |
356 | #ifdef CONFIG_CPU_DCACHE_DISABLE | |
357 | bic r0, r0, #CR_C | |
358 | #endif | |
359 | #ifdef CONFIG_CPU_BPREDICT_DISABLE | |
360 | bic r0, r0, #CR_Z | |
361 | #endif | |
362 | #ifdef CONFIG_CPU_ICACHE_DISABLE | |
363 | bic r0, r0, #CR_I | |
364 | #endif | |
365 | mov r5, #(domain_val(DOMAIN_USER, DOMAIN_MANAGER) | \ | |
366 | domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \ | |
367 | domain_val(DOMAIN_TABLE, DOMAIN_MANAGER) | \ | |
368 | domain_val(DOMAIN_IO, DOMAIN_CLIENT)) | |
369 | mcr p15, 0, r5, c3, c0, 0 @ load domain access register | |
370 | mcr p15, 0, r4, c2, c0, 0 @ load page table pointer | |
371 | b __turn_mmu_on | |
372 | ENDPROC(__enable_mmu) | |
373 | ||
374 | /* | |
375 | * Enable the MMU. This completely changes the structure of the visible | |
376 | * memory space. You will not be able to trace execution through this. | |
377 | * If you have an enquiry about this, *please* check the linux-arm-kernel | |
378 | * mailing list archives BEFORE sending another post to the list. | |
379 | * | |
380 | * r0 = cp#15 control register | |
865a4fae | 381 | * r1 = machine ID |
4c2896e8 | 382 | * r2 = atags or dtb pointer |
865a4fae | 383 | * r9 = processor ID |
00945010 RK |
384 | * r13 = *virtual* address to jump to upon completion |
385 | * | |
386 | * other registers depend on the function called upon completion | |
387 | */ | |
388 | .align 5 | |
389 | __turn_mmu_on: | |
390 | mov r0, r0 | |
391 | mcr p15, 0, r0, c1, c0, 0 @ write control reg | |
392 | mrc p15, 0, r3, c0, c0, 0 @ read id reg | |
393 | mov r3, r3 | |
394 | mov r3, r13 | |
395 | mov pc, r3 | |
396 | __enable_mmu_end: | |
397 | ENDPROC(__turn_mmu_on) | |
398 | ||
1da177e4 | 399 | |
f00ec48f | 400 | #ifdef CONFIG_SMP_ON_UP |
4a9cb360 | 401 | __INIT |
f00ec48f | 402 | __fixup_smp: |
e98ff0f5 RK |
403 | and r3, r9, #0x000f0000 @ architecture version |
404 | teq r3, #0x000f0000 @ CPU ID supported? | |
f00ec48f RK |
405 | bne __fixup_smp_on_up @ no, assume UP |
406 | ||
e98ff0f5 RK |
407 | bic r3, r9, #0x00ff0000 |
408 | bic r3, r3, #0x0000000f @ mask 0xff00fff0 | |
409 | mov r4, #0x41000000 | |
0eb0511d | 410 | orr r4, r4, #0x0000b000 |
e98ff0f5 RK |
411 | orr r4, r4, #0x00000020 @ val 0x4100b020 |
412 | teq r3, r4 @ ARM 11MPCore? | |
f00ec48f RK |
413 | moveq pc, lr @ yes, assume SMP |
414 | ||
415 | mrc p15, 0, r0, c0, c0, 5 @ read MPIDR | |
e98ff0f5 RK |
416 | and r0, r0, #0xc0000000 @ multiprocessing extensions and |
417 | teq r0, #0x80000000 @ not part of a uniprocessor system? | |
418 | moveq pc, lr @ yes, assume SMP | |
f00ec48f RK |
419 | |
420 | __fixup_smp_on_up: | |
421 | adr r0, 1f | |
0eb0511d | 422 | ldmia r0, {r3 - r5} |
f00ec48f | 423 | sub r3, r0, r3 |
0eb0511d RK |
424 | add r4, r4, r3 |
425 | add r5, r5, r3 | |
4a9cb360 | 426 | b __do_fixup_smp_on_up |
f00ec48f RK |
427 | ENDPROC(__fixup_smp) |
428 | ||
4f79a5dd | 429 | .align |
f00ec48f RK |
430 | 1: .word . |
431 | .word __smpalt_begin | |
432 | .word __smpalt_end | |
433 | ||
434 | .pushsection .data | |
435 | .globl smp_on_up | |
436 | smp_on_up: | |
437 | ALT_SMP(.long 1) | |
438 | ALT_UP(.long 0) | |
439 | .popsection | |
4a9cb360 | 440 | #endif |
f00ec48f | 441 | |
4a9cb360 RK |
442 | .text |
443 | __do_fixup_smp_on_up: | |
444 | cmp r4, r5 | |
445 | movhs pc, lr | |
446 | ldmia r4!, {r0, r6} | |
447 | ARM( str r6, [r0, r3] ) | |
448 | THUMB( add r0, r0, r3 ) | |
449 | #ifdef __ARMEB__ | |
450 | THUMB( mov r6, r6, ror #16 ) @ Convert word order for big-endian. | |
f00ec48f | 451 | #endif |
4a9cb360 RK |
452 | THUMB( strh r6, [r0], #2 ) @ For Thumb-2, store as two halfwords |
453 | THUMB( mov r6, r6, lsr #16 ) @ to be robust against misaligned r3. | |
454 | THUMB( strh r6, [r0] ) | |
455 | b __do_fixup_smp_on_up | |
456 | ENDPROC(__do_fixup_smp_on_up) | |
457 | ||
458 | ENTRY(fixup_smp) | |
459 | stmfd sp!, {r4 - r6, lr} | |
460 | mov r4, r0 | |
461 | add r5, r0, r1 | |
462 | mov r3, #0 | |
463 | bl __do_fixup_smp_on_up | |
464 | ldmfd sp!, {r4 - r6, pc} | |
465 | ENDPROC(fixup_smp) | |
f00ec48f | 466 | |
dc21af99 RK |
467 | #ifdef CONFIG_ARM_PATCH_PHYS_VIRT |
468 | ||
469 | /* __fixup_pv_table - patch the stub instructions with the delta between | |
470 | * PHYS_OFFSET and PAGE_OFFSET, which is assumed to be 16MiB aligned and | |
471 | * can be expressed by an immediate shifter operand. The stub instruction | |
472 | * has a form of '(add|sub) rd, rn, #imm'. | |
473 | */ | |
474 | __HEAD | |
475 | __fixup_pv_table: | |
476 | adr r0, 1f | |
477 | ldmia r0, {r3-r5, r7} | |
478 | sub r3, r0, r3 @ PHYS_OFFSET - PAGE_OFFSET | |
479 | add r4, r4, r3 @ adjust table start address | |
480 | add r5, r5, r3 @ adjust table end address | |
b511d75d NP |
481 | add r7, r7, r3 @ adjust __pv_phys_offset address |
482 | str r8, [r7] @ save computed PHYS_OFFSET to __pv_phys_offset | |
cada3c08 | 483 | #ifndef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT |
dc21af99 RK |
484 | mov r6, r3, lsr #24 @ constant for add/sub instructions |
485 | teq r3, r6, lsl #24 @ must be 16MiB aligned | |
cada3c08 RK |
486 | #else |
487 | mov r6, r3, lsr #16 @ constant for add/sub instructions | |
488 | teq r3, r6, lsl #16 @ must be 64kiB aligned | |
489 | #endif | |
b511d75d | 490 | THUMB( it ne @ cross section branch ) |
dc21af99 RK |
491 | bne __error |
492 | str r6, [r7, #4] @ save to __pv_offset | |
493 | b __fixup_a_pv_table | |
494 | ENDPROC(__fixup_pv_table) | |
495 | ||
496 | .align | |
497 | 1: .long . | |
498 | .long __pv_table_begin | |
499 | .long __pv_table_end | |
500 | 2: .long __pv_phys_offset | |
501 | ||
502 | .text | |
503 | __fixup_a_pv_table: | |
b511d75d NP |
504 | #ifdef CONFIG_THUMB2_KERNEL |
505 | #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT | |
506 | lsls r0, r6, #24 | |
507 | lsr r6, #8 | |
508 | beq 1f | |
509 | clz r7, r0 | |
510 | lsr r0, #24 | |
511 | lsl r0, r7 | |
512 | bic r0, 0x0080 | |
513 | lsrs r7, #1 | |
514 | orrcs r0, #0x0080 | |
515 | orr r0, r0, r7, lsl #12 | |
516 | #endif | |
517 | 1: lsls r6, #24 | |
518 | beq 4f | |
519 | clz r7, r6 | |
520 | lsr r6, #24 | |
521 | lsl r6, r7 | |
522 | bic r6, #0x0080 | |
523 | lsrs r7, #1 | |
524 | orrcs r6, #0x0080 | |
525 | orr r6, r6, r7, lsl #12 | |
526 | orr r6, #0x4000 | |
527 | b 4f | |
528 | 2: @ at this point the C flag is always clear | |
529 | add r7, r3 | |
530 | #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT | |
531 | ldrh ip, [r7] | |
532 | tst ip, 0x0400 @ the i bit tells us LS or MS byte | |
533 | beq 3f | |
534 | cmp r0, #0 @ set C flag, and ... | |
535 | biceq ip, 0x0400 @ immediate zero value has a special encoding | |
536 | streqh ip, [r7] @ that requires the i bit cleared | |
537 | #endif | |
538 | 3: ldrh ip, [r7, #2] | |
539 | and ip, 0x8f00 | |
540 | orrcc ip, r6 @ mask in offset bits 31-24 | |
541 | orrcs ip, r0 @ mask in offset bits 23-16 | |
542 | strh ip, [r7, #2] | |
543 | 4: cmp r4, r5 | |
544 | ldrcc r7, [r4], #4 @ use branch for delay slot | |
545 | bcc 2b | |
546 | bx lr | |
547 | #else | |
cada3c08 RK |
548 | #ifdef CONFIG_ARM_PATCH_PHYS_VIRT_16BIT |
549 | and r0, r6, #255 @ offset bits 23-16 | |
550 | mov r6, r6, lsr #8 @ offset bits 31-24 | |
551 | #else | |
552 | mov r0, #0 @ just in case... | |
553 | #endif | |
dc21af99 RK |
554 | b 3f |
555 | 2: ldr ip, [r7, r3] | |
556 | bic ip, ip, #0x000000ff | |
cada3c08 RK |
557 | tst ip, #0x400 @ rotate shift tells us LS or MS byte |
558 | orrne ip, ip, r6 @ mask in offset bits 31-24 | |
559 | orreq ip, ip, r0 @ mask in offset bits 23-16 | |
dc21af99 RK |
560 | str ip, [r7, r3] |
561 | 3: cmp r4, r5 | |
562 | ldrcc r7, [r4], #4 @ use branch for delay slot | |
563 | bcc 2b | |
564 | mov pc, lr | |
b511d75d | 565 | #endif |
dc21af99 RK |
566 | ENDPROC(__fixup_a_pv_table) |
567 | ||
568 | ENTRY(fixup_pv_table) | |
569 | stmfd sp!, {r4 - r7, lr} | |
570 | ldr r2, 2f @ get address of __pv_phys_offset | |
571 | mov r3, #0 @ no offset | |
572 | mov r4, r0 @ r0 = table start | |
573 | add r5, r0, r1 @ r1 = table size | |
574 | ldr r6, [r2, #4] @ get __pv_offset | |
575 | bl __fixup_a_pv_table | |
576 | ldmfd sp!, {r4 - r7, pc} | |
577 | ENDPROC(fixup_pv_table) | |
578 | ||
579 | .align | |
580 | 2: .long __pv_phys_offset | |
581 | ||
582 | .data | |
583 | .globl __pv_phys_offset | |
584 | .type __pv_phys_offset, %object | |
585 | __pv_phys_offset: | |
586 | .long 0 | |
587 | .size __pv_phys_offset, . - __pv_phys_offset | |
588 | __pv_offset: | |
589 | .long 0 | |
590 | #endif | |
591 | ||
75d90832 | 592 | #include "head-common.S" |