Gitiles
Code Review Sign In
review.evervolv.com / android_kernel_oneplus_msm8996 / 55bdd694116597d2f16510b121463cd579ba78da / . / arch / arm / kernel / head-nommu.S
blob: 8812ce88f7a1f289e64e8c787efc5a4db3df0ec9 [file] [log] [blame]
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]1/*
2 * linux/arch/arm/kernel/head-nommu.S
3 *
4 * Copyright (C) 1994-2002 Russell King
5 * Copyright (C) 2003-2006 Hyok S. Choi
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 * Common kernel startup code (non-paged MM)
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]12 *
13 */
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]14#include <linux/linkage.h>
15#include <linux/init.h>
16
17#include <asm/assembler.h>
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]18#include <asm/ptrace.h>
Uwe Zeisberger2eb9d312006-05-05 15:11:14 +0100[diff] [blame]19#include <asm/asm-offsets.h>
Russell King15d07dc2012-03-28 18:30:01 +0100[diff] [blame]20#include <asm/cp15.h>
Hyok S. Choi3b920ce2006-04-24 09:45:35 +0100[diff] [blame]21#include <asm/thread_info.h>
Catalin Marinas55bdd692010-05-21 18:06:41 +0100[diff] [blame^]22#include <asm/v7m.h>
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]23
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]24/*
25 * Kernel startup entry point.
26 * ---------------------------
27 *
28 * This is normally called from the decompressor code. The requirements
29 * are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
30 * r1 = machine nr.
31 *
32 * See linux/arch/arm/tools/mach-types for the complete list of machine
33 * numbers for r1.
34 *
35 */
Dave Martin540b5732011-07-13 15:53:30 +0100[diff] [blame]36
Tim Abbott2abc1c52009-10-02 16:32:46 -0400[diff] [blame]37 __HEAD
Uwe Kleine-Königbc7dea02011-12-09 20:52:10 +0100[diff] [blame]38
39#ifdef CONFIG_CPU_THUMBONLY
40 .thumb
41ENTRY(stext)
42#else
43 .arm
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]44ENTRY(stext)
Dave Martin540b5732011-07-13 15:53:30 +0100[diff] [blame]45
46 THUMB( adr r9, BSYM(1f) ) @ Kernel is always entered in ARM.
47 THUMB( bx r9 ) @ If this is a Thumb-2 kernel,
48 THUMB( .thumb ) @ switch to Thumb now.
49 THUMB(1: )
Uwe Kleine-Königbc7dea02011-12-09 20:52:10 +0100[diff] [blame]50#endif
Dave Martin540b5732011-07-13 15:53:30 +0100[diff] [blame]51
Catalin Marinasb86040a2009-07-24 12:32:54 +0100[diff] [blame]52 setmode PSR_F_BIT | PSR_I_BIT | SVC_MODE, r9 @ ensure svc mode
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]53 @ and irqs disabled
Catalin Marinas55bdd692010-05-21 18:06:41 +0100[diff] [blame^]54#if defined(CONFIG_CPU_CP15)
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]55 mrc p15, 0, r9, c0, c0 @ get processor id
Catalin Marinas55bdd692010-05-21 18:06:41 +0100[diff] [blame^]56#elif defined(CONFIG_CPU_V7M)
57 ldr r9, =BASEADDR_V7M_SCB
58 ldr r9, [r9, V7M_SCB_CPUID]
59#else
60 ldr r9, =CONFIG_PROCESSOR_ID
Hyok S. Choif12d0d72006-09-26 17:36:37 +0900[diff] [blame]61#endif
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]62 bl __lookup_processor_type @ r5=procinfo r9=cpuid
63 movs r10, r5 @ invalid processor (r5=0)?
64 beq __error_p @ yes, error 'p'
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]65
Catalin Marinasb86040a2009-07-24 12:32:54 +0100[diff] [blame]66 adr lr, BSYM(__after_proc_init) @ return (PIC) address
67 ARM( add pc, r10, #PROCINFO_INITFUNC )
68 THUMB( add r12, r10, #PROCINFO_INITFUNC )
69 THUMB( mov pc, r12 )
Catalin Marinas93ed3972008-08-28 11:22:32 +0100[diff] [blame]70ENDPROC(stext)
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]71
72/*
73 * Set the Control Register and Read the process ID.
74 */
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]75__after_proc_init:
Hyok S. Choif12d0d72006-09-26 17:36:37 +0900[diff] [blame]76#ifdef CONFIG_CPU_CP15
Catalin Marinas05efde92009-07-24 12:34:59 +0100[diff] [blame]77 /*
78 * CP15 system control register value returned in r0 from
79 * the CPU init function.
80 */
Armando Visconti76e09202012-12-04 10:34:39 +0100[diff] [blame]81#if defined(CONFIG_ALIGNMENT_TRAP) && __LINUX_ARM_ARCH__ < 6
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]82 orr r0, r0, #CR_A
83#else
84 bic r0, r0, #CR_A
85#endif
86#ifdef CONFIG_CPU_DCACHE_DISABLE
87 bic r0, r0, #CR_C
88#endif
89#ifdef CONFIG_CPU_BPREDICT_DISABLE
90 bic r0, r0, #CR_Z
91#endif
92#ifdef CONFIG_CPU_ICACHE_DISABLE
93 bic r0, r0, #CR_I
94#endif
Hyok S. Choi6afd6fa2006-09-28 21:46:34 +0900[diff] [blame]95#ifdef CONFIG_CPU_HIGH_VECTOR
96 orr r0, r0, #CR_V
97#else
98 bic r0, r0, #CR_V
99#endif
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]100 mcr p15, 0, r0, c1, c0, 0 @ write control reg
Hyok S. Choif12d0d72006-09-26 17:36:37 +0900[diff] [blame]101#endif /* CONFIG_CPU_CP15 */
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]102
Russell Kingf131a082010-10-01 15:42:02 +0100[diff] [blame]103 b __mmap_switched @ clear the BSS and jump
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]104 @ to start_kernel
Catalin Marinas93ed3972008-08-28 11:22:32 +0100[diff] [blame]105ENDPROC(__after_proc_init)
Hyok S. Choi3b920ce2006-04-24 09:45:35 +0100[diff] [blame]106 .ltorg
Hyok S. Choi75d90832006-03-27 14:58:25 +0100[diff] [blame]107
108#include "head-common.S"