linux-stable/arch/s390/kernel/head64.S
Heiko Carstens 971a9ca625 s390/early: move functions which may not access bss section to extra file
Move functions which may not access bss section to extra file. This
makes it easier to verify that all early functions which may not rely
on an initialized bss section are not accessing it.

Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-05-09 10:55:01 +02:00

114 lines
3.3 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright IBM Corp. 1999, 2010
*
* Author(s): Hartmut Penner <hp@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Rob van der Heij <rvdhei@iae.nl>
* Heiko Carstens <heiko.carstens@de.ibm.com>
*
*/
#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/page.h>
__HEAD
ENTRY(startup_continue)
tm __LC_STFLE_FAC_LIST+5,0x80 # LPP available ?
jz 0f
xc __LC_LPP+1(7,0),__LC_LPP+1 # clear lpp and current_pid
mvi __LC_LPP,0x80 # and set LPP_MAGIC
.insn s,0xb2800000,__LC_LPP # load program parameter
0: larl %r1,tod_clock_base
mvc 0(16,%r1),__LC_BOOT_CLOCK
larl %r13,.LPG1 # get base
lctlg %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
lg %r12,.Lparmaddr-.LPG1(%r13) # pointer to parameter area
# move IPL device to lowcore
larl %r0,boot_vdso_data
stg %r0,__LC_VDSO_PER_CPU
#
# Setup stack
#
larl %r14,init_task
stg %r14,__LC_CURRENT
larl %r15,init_thread_union
aghi %r15,1<<(PAGE_SHIFT+THREAD_SIZE_ORDER) # init_task_union + THREAD_SIZE
stg %r15,__LC_KERNEL_STACK # set end of kernel stack
aghi %r15,-160
#
# Early setup functions that may not rely on an initialized bss section,
# like moving the initrd. Returns with an initialized bss section.
#
brasl %r14,startup_init_nobss
#
# Early machine initialization and detection functions.
#
brasl %r14,startup_init
lpswe .Lentry-.LPG1(13) # jump to _stext in primary-space,
# virtual and never return ...
.align 16
.LPG1:
.Lentry:.quad 0x0000000180000000,_stext
.Lctl: .quad 0x04040000 # cr0: AFP registers & secondary space
.quad 0 # cr1: primary space segment table
.quad .Lduct # cr2: dispatchable unit control table
.quad 0 # cr3: instruction authorization
.quad 0xffff # cr4: instruction authorization
.quad .Lduct # cr5: primary-aste origin
.quad 0 # cr6: I/O interrupts
.quad 0 # cr7: secondary space segment table
.quad 0 # cr8: access registers translation
.quad 0 # cr9: tracing off
.quad 0 # cr10: tracing off
.quad 0 # cr11: tracing off
.quad 0 # cr12: tracing off
.quad 0 # cr13: home space segment table
.quad 0xc0000000 # cr14: machine check handling off
.quad .Llinkage_stack # cr15: linkage stack operations
.Lpcmsk:.quad 0x0000000180000000
.L4malign:.quad 0xffffffffffc00000
.Lscan2g:.quad 0x80000000 + 0x20000 - 8 # 2GB + 128K - 8
.Lnop: .long 0x07000700
.Lparmaddr:
.quad PARMAREA
.align 64
.Lduct: .long 0,.Laste,.Laste,0,.Lduald,0,0,0
.long 0,0,0,0,0,0,0,0
.Laste: .quad 0,0xffffffffffffffff,0,0,0,0,0,0
.align 128
.Lduald:.rept 8
.long 0x80000000,0,0,0 # invalid access-list entries
.endr
.Llinkage_stack:
.long 0,0,0x89000000,0,0,0,0x8a000000,0
ENTRY(_ehead)
.org 0x100000 - 0x11000 # head.o ends at 0x11000
#
# startup-code, running in absolute addressing mode
#
ENTRY(_stext)
basr %r13,0 # get base
.LPG3:
# check control registers
stctg %c0,%c15,0(%r15)
oi 6(%r15),0x60 # enable sigp emergency & external call
oi 4(%r15),0x10 # switch on low address proctection
lctlg %c0,%c15,0(%r15)
lam 0,15,.Laregs-.LPG3(%r13) # load acrs needed by uaccess
brasl %r14,start_kernel # go to C code
#
# We returned from start_kernel ?!? PANIK
#
basr %r13,0
lpswe .Ldw-.(%r13) # load disabled wait psw
.align 8
.Ldw: .quad 0x0002000180000000,0x0000000000000000
.Laregs:.long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0