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gerrit-public.fairphone.software / kernel / msm-4.19 / eacb1962d4594b9d382b40acd73a9c9492718f74 / . / arch / powerpc / boot / crt0.S
blob: 70e65b13e0336fd86c02f3c602181be94c3ae3e0 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1/*
2 * Copyright (C) Paul Mackerras 1997.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * NOTE: this code runs in 32 bit mode and is packaged as ELF32.
10 */
11
Olaf Heringdecd3002005-08-08 13:24:38 +1000[diff] [blame]12#include "ppc_asm.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]13
14 .text
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]15 /* a procedure descriptor used when booting this as a COFF file */
16_zimage_start_opd:
17 .long _zimage_start, 0, 0, 0
18
Olaf Hering67a1b682005-10-28 17:46:49 -0700[diff] [blame]19 .globl _zimage_start
20_zimage_start:
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]21 /* Work out the offset between the address we were linked at
22 and the address where we're running. */
Olaf Hering68643cf2005-11-17 22:09:02 +0100[diff] [blame]23 bl 1f
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]241: mflr r0
Olaf Hering68643cf2005-11-17 22:09:02 +0100[diff] [blame]25 lis r9,1b@ha
26 addi r9,r9,1b@l
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]27 subf. r0,r9,r0
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]28 beq 3f /* if running at same address as linked */
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]29
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]30 /* The .got2 section contains a list of addresses, so add
31 the address offset onto each entry. */
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]32 lis r9,__got2_start@ha
33 addi r9,r9,__got2_start@l
34 lis r8,__got2_end@ha
35 addi r8,r8,__got2_end@l
36 subf. r8,r9,r8
Olaf Hering68643cf2005-11-17 22:09:02 +0100[diff] [blame]37 beq 3f
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]38 srwi. r8,r8,2
39 mtctr r8
40 add r9,r0,r9
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]412: lwz r8,0(r9)
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]42 add r8,r8,r0
43 stw r8,0(r9)
44 addi r9,r9,4
Olaf Hering68643cf2005-11-17 22:09:02 +0100[diff] [blame]45 bdnz 2b
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]46
Paul Mackerras66a45dd2006-01-14 15:04:06 +1100[diff] [blame]47 /* Do a cache flush for our text, in case OF didn't */
Olaf Heringeacb1962006-03-04 13:15:40 +0100[diff] [blame^]483: lis r9,_start@ha
49 addi r9,r9,_start@l
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]50 add r9,r0,r9
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]51 lis r8,_etext@ha
52 addi r8,r8,_etext@l
Olaf Heringa4497232005-10-28 17:46:48 -0700[diff] [blame]53 add r8,r0,r8
Olaf Hering68643cf2005-11-17 22:09:02 +0100[diff] [blame]544: dcbf r0,r9
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]55 icbi r0,r9
56 addi r9,r9,0x20
Olaf Heringeacb1962006-03-04 13:15:40 +0100[diff] [blame^]57 cmplw cr0,r9,r8
Olaf Hering68643cf2005-11-17 22:09:02 +0100[diff] [blame]58 blt 4b
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]59 sync
60 isync
61
Olaf Hering7e658112005-10-28 17:46:50 -0700[diff] [blame]62 mr r6,r1
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]63 b start
64