[ARM] nommu: start-up code

This patch adds nommu version start-up code head-nommu.S.
The common part of the start-up codes is moved to head-common.S.

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Hyok S. Choi 2006-03-27 14:58:25 +01:00 committed by Russell King
parent 10c2df6506
commit 75d90832d5
4 changed files with 302 additions and 207 deletions

View file

@ -69,7 +69,7 @@ AFLAGS +=$(CFLAGS_ABI) $(arch-y) $(tune-y) -msoft-float
CHECKFLAGS += -D__arm__
#Default value
head-y := arch/arm/kernel/head.o arch/arm/kernel/init_task.o
head-y := arch/arm/kernel/head$(MMUEXT).o arch/arm/kernel/init_task.o
textofs-y := 0x00008000
machine-$(CONFIG_ARCH_RPC) := rpc

View file

@ -0,0 +1,217 @@
/*
* linux/arch/arm/kernel/head-common.S
*
* Copyright (C) 1994-2002 Russell King
* Copyright (c) 2003 ARM Limited
* All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
.type __switch_data, %object
__switch_data:
.long __mmap_switched
.long __data_loc @ r4
.long __data_start @ r5
.long __bss_start @ r6
.long _end @ r7
.long processor_id @ r4
.long __machine_arch_type @ r5
.long cr_alignment @ r6
.long init_thread_union + THREAD_START_SP @ sp
/*
* The following fragment of code is executed with the MMU on in MMU mode,
* and uses absolute addresses; this is not position independent.
*
* r0 = cp#15 control register
* r1 = machine ID
* r9 = processor ID
*/
.type __mmap_switched, %function
__mmap_switched:
adr r3, __switch_data + 4
ldmia r3!, {r4, r5, r6, r7}
cmp r4, r5 @ Copy data segment if needed
1: cmpne r5, r6
ldrne fp, [r4], #4
strne fp, [r5], #4
bne 1b
mov fp, #0 @ Clear BSS (and zero fp)
1: cmp r6, r7
strcc fp, [r6],#4
bcc 1b
ldmia r3, {r4, r5, r6, sp}
str r9, [r4] @ Save processor ID
str r1, [r5] @ Save machine type
bic r4, r0, #CR_A @ Clear 'A' bit
stmia r6, {r0, r4} @ Save control register values
b start_kernel
/*
* Exception handling. Something went wrong and we can't proceed. We
* ought to tell the user, but since we don't have any guarantee that
* we're even running on the right architecture, we do virtually nothing.
*
* If CONFIG_DEBUG_LL is set we try to print out something about the error
* and hope for the best (useful if bootloader fails to pass a proper
* machine ID for example).
*/
.type __error_p, %function
__error_p:
#ifdef CONFIG_DEBUG_LL
adr r0, str_p1
bl printascii
b __error
str_p1: .asciz "\nError: unrecognized/unsupported processor variant.\n"
.align
#endif
.type __error_a, %function
__error_a:
#ifdef CONFIG_DEBUG_LL
mov r4, r1 @ preserve machine ID
adr r0, str_a1
bl printascii
mov r0, r4
bl printhex8
adr r0, str_a2
bl printascii
adr r3, 3f
ldmia r3, {r4, r5, r6} @ get machine desc list
sub r4, r3, r4 @ get offset between virt&phys
add r5, r5, r4 @ convert virt addresses to
add r6, r6, r4 @ physical address space
1: ldr r0, [r5, #MACHINFO_TYPE] @ get machine type
bl printhex8
mov r0, #'\t'
bl printch
ldr r0, [r5, #MACHINFO_NAME] @ get machine name
add r0, r0, r4
bl printascii
mov r0, #'\n'
bl printch
add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc
cmp r5, r6
blo 1b
adr r0, str_a3
bl printascii
b __error
str_a1: .asciz "\nError: unrecognized/unsupported machine ID (r1 = 0x"
str_a2: .asciz ").\n\nAvailable machine support:\n\nID (hex)\tNAME\n"
str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n"
.align
#endif
.type __error, %function
__error:
#ifdef CONFIG_ARCH_RPC
/*
* Turn the screen red on a error - RiscPC only.
*/
mov r0, #0x02000000
mov r3, #0x11
orr r3, r3, r3, lsl #8
orr r3, r3, r3, lsl #16
str r3, [r0], #4
str r3, [r0], #4
str r3, [r0], #4
str r3, [r0], #4
#endif
1: mov r0, r0
b 1b
/*
* Read processor ID register (CP#15, CR0), and look up in the linker-built
* supported processor list. Note that we can't use the absolute addresses
* for the __proc_info lists since we aren't running with the MMU on
* (and therefore, we are not in the correct address space). We have to
* calculate the offset.
*
* r9 = cpuid
* Returns:
* r3, r4, r6 corrupted
* r5 = proc_info pointer in physical address space
* r9 = cpuid (preserved)
*/
.type __lookup_processor_type, %function
__lookup_processor_type:
adr r3, 3f
ldmda r3, {r5 - r7}
sub r3, r3, r7 @ get offset between virt&phys
add r5, r5, r3 @ convert virt addresses to
add r6, r6, r3 @ physical address space
1: ldmia r5, {r3, r4} @ value, mask
and r4, r4, r9 @ mask wanted bits
teq r3, r4
beq 2f
add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list)
cmp r5, r6
blo 1b
mov r5, #0 @ unknown processor
2: mov pc, lr
/*
* This provides a C-API version of the above function.
*/
ENTRY(lookup_processor_type)
stmfd sp!, {r4 - r7, r9, lr}
mov r9, r0
bl __lookup_processor_type
mov r0, r5
ldmfd sp!, {r4 - r7, r9, pc}
/*
* Look in include/asm-arm/procinfo.h and arch/arm/kernel/arch.[ch] for
* more information about the __proc_info and __arch_info structures.
*/
.long __proc_info_begin
.long __proc_info_end
3: .long .
.long __arch_info_begin
.long __arch_info_end
/*
* Lookup machine architecture in the linker-build list of architectures.
* Note that we can't use the absolute addresses for the __arch_info
* lists since we aren't running with the MMU on (and therefore, we are
* not in the correct address space). We have to calculate the offset.
*
* r1 = machine architecture number
* Returns:
* r3, r4, r6 corrupted
* r5 = mach_info pointer in physical address space
*/
.type __lookup_machine_type, %function
__lookup_machine_type:
adr r3, 3b
ldmia r3, {r4, r5, r6}
sub r3, r3, r4 @ get offset between virt&phys
add r5, r5, r3 @ convert virt addresses to
add r6, r6, r3 @ physical address space
1: ldr r3, [r5, #MACHINFO_TYPE] @ get machine type
teq r3, r1 @ matches loader number?
beq 2f @ found
add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc
cmp r5, r6
blo 1b
mov r5, #0 @ unknown machine
2: mov pc, lr
/*
* This provides a C-API version of the above function.
*/
ENTRY(lookup_machine_type)
stmfd sp!, {r4 - r6, lr}
mov r1, r0
bl __lookup_machine_type
mov r0, r5
ldmfd sp!, {r4 - r6, pc}

View file

@ -0,0 +1,83 @@
/*
* linux/arch/arm/kernel/head-nommu.S
*
* Copyright (C) 1994-2002 Russell King
* Copyright (C) 2003-2006 Hyok S. Choi
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Common kernel startup code (non-paged MM)
* for 32-bit CPUs which has a process ID register(CP15).
*
*/
#include <linux/config.h>
#include <linux/linkage.h>
#include <linux/init.h>
#include <asm/assembler.h>
#include <asm/mach-types.h>
#include <asm/procinfo.h>
#include <asm/ptrace.h>
#include <asm/constants.h>
#include <asm/system.h>
#define PROCINFO_INITFUNC 12
/*
* Kernel startup entry point.
* ---------------------------
*
* This is normally called from the decompressor code. The requirements
* are: MMU = off, D-cache = off, I-cache = dont care, r0 = 0,
* r1 = machine nr.
*
* See linux/arch/arm/tools/mach-types for the complete list of machine
* numbers for r1.
*
*/
__INIT
.type stext, %function
ENTRY(stext)
msr cpsr_c, #PSR_F_BIT | PSR_I_BIT | MODE_SVC @ ensure svc mode
@ and irqs disabled
mrc p15, 0, r9, c0, c0 @ get processor id
bl __lookup_processor_type @ r5=procinfo r9=cpuid
movs r10, r5 @ invalid processor (r5=0)?
beq __error_p @ yes, error 'p'
bl __lookup_machine_type @ r5=machinfo
movs r8, r5 @ invalid machine (r5=0)?
beq __error_a @ yes, error 'a'
ldr r13, __switch_data @ address to jump to after
@ the initialization is done
adr lr, __after_proc_init @ return (PIC) address
add pc, r10, #PROCINFO_INITFUNC
/*
* Set the Control Register and Read the process ID.
*/
.type __after_proc_init, %function
__after_proc_init:
mrc p15, 0, r0, c1, c0, 0 @ read control reg
#ifdef CONFIG_ALIGNMENT_TRAP
orr r0, r0, #CR_A
#else
bic r0, r0, #CR_A
#endif
#ifdef CONFIG_CPU_DCACHE_DISABLE
bic r0, r0, #CR_C
#endif
#ifdef CONFIG_CPU_BPREDICT_DISABLE
bic r0, r0, #CR_Z
#endif
#ifdef CONFIG_CPU_ICACHE_DISABLE
bic r0, r0, #CR_I
#endif
mcr p15, 0, r0, c1, c0, 0 @ write control reg
mov pc, r13 @ clear the BSS and jump
@ to start_kernel
#include "head-common.S"

View file

@ -103,49 +103,6 @@ ENTRY(stext)
adr lr, __enable_mmu @ return (PIC) address
add pc, r10, #PROCINFO_INITFUNC
.type __switch_data, %object
__switch_data:
.long __mmap_switched
.long __data_loc @ r4
.long __data_start @ r5
.long __bss_start @ r6
.long _end @ r7
.long processor_id @ r4
.long __machine_arch_type @ r5
.long cr_alignment @ r6
.long init_thread_union + THREAD_START_SP @ sp
/*
* The following fragment of code is executed with the MMU on, and uses
* absolute addresses; this is not position independent.
*
* r0 = cp#15 control register
* r1 = machine ID
* r9 = processor ID
*/
.type __mmap_switched, %function
__mmap_switched:
adr r3, __switch_data + 4
ldmia r3!, {r4, r5, r6, r7}
cmp r4, r5 @ Copy data segment if needed
1: cmpne r5, r6
ldrne fp, [r4], #4
strne fp, [r5], #4
bne 1b
mov fp, #0 @ Clear BSS (and zero fp)
1: cmp r6, r7
strcc fp, [r6],#4
bcc 1b
ldmia r3, {r4, r5, r6, sp}
str r9, [r4] @ Save processor ID
str r1, [r5] @ Save machine type
bic r4, r0, #CR_A @ Clear 'A' bit
stmia r6, {r0, r4} @ Save control register values
b start_kernel
#if defined(CONFIG_SMP)
.type secondary_startup, #function
ENTRY(secondary_startup)
@ -368,166 +325,4 @@ __create_page_tables:
mov pc, lr
.ltorg
/*
* Exception handling. Something went wrong and we can't proceed. We
* ought to tell the user, but since we don't have any guarantee that
* we're even running on the right architecture, we do virtually nothing.
*
* If CONFIG_DEBUG_LL is set we try to print out something about the error
* and hope for the best (useful if bootloader fails to pass a proper
* machine ID for example).
*/
.type __error_p, %function
__error_p:
#ifdef CONFIG_DEBUG_LL
adr r0, str_p1
bl printascii
b __error
str_p1: .asciz "\nError: unrecognized/unsupported processor variant.\n"
.align
#endif
.type __error_a, %function
__error_a:
#ifdef CONFIG_DEBUG_LL
mov r4, r1 @ preserve machine ID
adr r0, str_a1
bl printascii
mov r0, r4
bl printhex8
adr r0, str_a2
bl printascii
adr r3, 3f
ldmia r3, {r4, r5, r6} @ get machine desc list
sub r4, r3, r4 @ get offset between virt&phys
add r5, r5, r4 @ convert virt addresses to
add r6, r6, r4 @ physical address space
1: ldr r0, [r5, #MACHINFO_TYPE] @ get machine type
bl printhex8
mov r0, #'\t'
bl printch
ldr r0, [r5, #MACHINFO_NAME] @ get machine name
add r0, r0, r4
bl printascii
mov r0, #'\n'
bl printch
add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc
cmp r5, r6
blo 1b
adr r0, str_a3
bl printascii
b __error
str_a1: .asciz "\nError: unrecognized/unsupported machine ID (r1 = 0x"
str_a2: .asciz ").\n\nAvailable machine support:\n\nID (hex)\tNAME\n"
str_a3: .asciz "\nPlease check your kernel config and/or bootloader.\n"
.align
#endif
.type __error, %function
__error:
#ifdef CONFIG_ARCH_RPC
/*
* Turn the screen red on a error - RiscPC only.
*/
mov r0, #0x02000000
mov r3, #0x11
orr r3, r3, r3, lsl #8
orr r3, r3, r3, lsl #16
str r3, [r0], #4
str r3, [r0], #4
str r3, [r0], #4
str r3, [r0], #4
#endif
1: mov r0, r0
b 1b
/*
* Read processor ID register (CP#15, CR0), and look up in the linker-built
* supported processor list. Note that we can't use the absolute addresses
* for the __proc_info lists since we aren't running with the MMU on
* (and therefore, we are not in the correct address space). We have to
* calculate the offset.
*
* r9 = cpuid
* Returns:
* r3, r4, r6 corrupted
* r5 = proc_info pointer in physical address space
* r9 = cpuid (preserved)
*/
.type __lookup_processor_type, %function
__lookup_processor_type:
adr r3, 3f
ldmda r3, {r5 - r7}
sub r3, r3, r7 @ get offset between virt&phys
add r5, r5, r3 @ convert virt addresses to
add r6, r6, r3 @ physical address space
1: ldmia r5, {r3, r4} @ value, mask
and r4, r4, r9 @ mask wanted bits
teq r3, r4
beq 2f
add r5, r5, #PROC_INFO_SZ @ sizeof(proc_info_list)
cmp r5, r6
blo 1b
mov r5, #0 @ unknown processor
2: mov pc, lr
/*
* This provides a C-API version of the above function.
*/
ENTRY(lookup_processor_type)
stmfd sp!, {r4 - r7, r9, lr}
mov r9, r0
bl __lookup_processor_type
mov r0, r5
ldmfd sp!, {r4 - r7, r9, pc}
/*
* Look in include/asm-arm/procinfo.h and arch/arm/kernel/arch.[ch] for
* more information about the __proc_info and __arch_info structures.
*/
.long __proc_info_begin
.long __proc_info_end
3: .long .
.long __arch_info_begin
.long __arch_info_end
/*
* Lookup machine architecture in the linker-build list of architectures.
* Note that we can't use the absolute addresses for the __arch_info
* lists since we aren't running with the MMU on (and therefore, we are
* not in the correct address space). We have to calculate the offset.
*
* r1 = machine architecture number
* Returns:
* r3, r4, r6 corrupted
* r5 = mach_info pointer in physical address space
*/
.type __lookup_machine_type, %function
__lookup_machine_type:
adr r3, 3b
ldmia r3, {r4, r5, r6}
sub r3, r3, r4 @ get offset between virt&phys
add r5, r5, r3 @ convert virt addresses to
add r6, r6, r3 @ physical address space
1: ldr r3, [r5, #MACHINFO_TYPE] @ get machine type
teq r3, r1 @ matches loader number?
beq 2f @ found
add r5, r5, #SIZEOF_MACHINE_DESC @ next machine_desc
cmp r5, r6
blo 1b
mov r5, #0 @ unknown machine
2: mov pc, lr
/*
* This provides a C-API version of the above function.
*/
ENTRY(lookup_machine_type)
stmfd sp!, {r4 - r6, lr}
mov r1, r0
bl __lookup_machine_type
mov r0, r5
ldmfd sp!, {r4 - r6, pc}
#include "head-common.S"