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linux/arch/s390/kernel/head64.S

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Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
/*
s390/comments: unify copyright messages and remove file names Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 09:15:04 +00:00
* Copyright IBM Corp. 1999, 2010
[PATCH] s390: merge common parts of head.S and head64.S Merge common parts of head.S and head64.S into head.S and move architecture specific parts to head31.S and head64.S respectively. Saves us ~500 lines of duplicated assembly code. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07 08:59:12 +00:00
*
* 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>
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
*
*/
[S390] add support for compressed kernels Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 21:37:53 +00:00
#include <linux/init.h>
[S390] fix s390 assembler code alignments The alignment is missing for various global symbols in s390 assembly code. With a recent gcc and an instruction like stgrl this can lead to a specification exception if the instruction uses such a mis-aligned address. Specify the alignment explicitely and while add it define __ALIGN for s390 and use the ENTRY define to save some lines of code. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 08:48:19 +00:00
#include <linux/linkage.h>
[S390] add support for compressed kernels Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 21:37:53 +00:00
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/page.h>
[S390] head.S code moving. There is almost no room left for any new code between 0x10000 and 0x10480. Move the code from 0x10000 to 0x11000. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-29 12:58:17 +00:00
[S390] add support for compressed kernels Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 21:37:53 +00:00
__HEAD
[S390] fix s390 assembler code alignments The alignment is missing for various global symbols in s390 assembly code. With a recent gcc and an instruction like stgrl this can lead to a specification exception if the instruction uses such a mis-aligned address. Specify the alignment explicitely and while add it define __ALIGN for s390 and use the ENTRY define to save some lines of code. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 08:48:19 +00:00
ENTRY(startup_continue)
[S390] add support for compressed kernels Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 21:37:53 +00:00
larl %r1,sched_clock_base_cc
mvc 0(8,%r1),__LC_LAST_UPDATE_CLOCK
larl %r13,.LPG1 # get base
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
lctlg %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
lg %r12,.Lparmaddr-.LPG1(%r13) # pointer to parameter area
# move IPL device to lowcore
[PATCH] fast vdso implementation for CLOCK_THREAD_CPUTIME_ID The extract cpu time instruction (ectg) instruction allows the user process to get the current thread cputime without calling into the kernel. The code that uses the instruction needs to switch to the access registers mode to get access to the per-cpu info page that contains the two base values that are needed to calculate the current cputime from the CPU timer with the ectg instruction. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-31 14:11:42 +00:00
lghi %r0,__LC_PASTE
stg %r0,__LC_VDSO_PER_CPU
[S390] convert some assembler to C. Convert GET_IPL_DEVICE assembler macro to C function. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20 13:59:15 +00:00
#
# Setup stack
#
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
larl %r15,init_thread_union
[S390] Initialize __LC_THREAD_INFO early. "lockdep: Fix backtraces" reveales a bug in early setup code: when lockdep tries to save a stack backtrace before setup_arch has been called the lowcore pointer for the current thread info pointer isn't initialized yet. However our save stack backtrace code relies on it. If the pointer isn't initialized the saved backtrace will have zero entries. lockdep however relies (correctly) on the fact that that cannot happen. A write access to some random memory region is the result. Fix this by initializing the thread info pointer early. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-09-11 08:28:58 +00:00
stg %r15,__LC_THREAD_INFO # cache thread info in lowcore
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
lg %r14,__TI_task(%r15) # cache current in lowcore
stg %r14,__LC_CURRENT
aghi %r15,1<<(PAGE_SHIFT+THREAD_ORDER) # init_task_union + THREAD_SIZE
stg %r15,__LC_KERNEL_STACK # set end of kernel stack
aghi %r15,-160
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#
[S390] boot from NSS support Add support to boot from a named saved segment (NSS). Signed-off-by: Hongjie Yang <hongjie@us.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:24 +00:00
# Save ipl parameters, clear bss memory, initialize storage key for kernel pages,
# and create a kernel NSS if the SAVESYS= parm is defined
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#
[S390] boot from NSS support Add support to boot from a named saved segment (NSS). Signed-off-by: Hongjie Yang <hongjie@us.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:24 +00:00
brasl %r14,startup_init
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
lpswe .Lentry-.LPG1(13) # jump to _stext in primary-space,
# virtual and never return ...
.align 16
[S390] add support for compressed kernels Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 21:37:53 +00:00
.LPG1:
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
.Lentry:.quad 0x0000000180000000,_stext
[S390] initial cr0 bits Remove outdated bits from the initial cr0 register. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 08:48:29 +00:00
.Lctl: .quad 0x04040000 # cr0: AFP registers & secondary space
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
.quad 0 # cr1: primary space segment table
.quad .Lduct # cr2: dispatchable unit control table
.quad 0 # cr3: instruction authorization
.quad 0 # cr4: instruction authorization
[S390] Fixed handling of access register mode faults. Replaced check_user_space() + __check_access_register with the new check_space(). The old functions made wrong assumptions about kernel and user space when the kernel and user address spaces are switched (kernel in home space, user in primary/secondary space). Secondly the user process can switch to the accress register mode if it is running in primary or secondary mode. In addition it can load an arbitrary value to the access registers. If any other value than 0 for primary space or 1 for secondary space is loaded and memory is accessed using the base register related to the access register, the program should be terminated with a SIGSEGV. To achieve that the DUALD pointer in the DUCT and the PSALD pointer in the PASTE need to point to an array of 8 invalid access-list entries to get a ALEN-translation exception if an invalid alet is used. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-05 22:35:54 +00:00
.quad .Lduct # cr5: primary-aste origin
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
.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 0 # cr15: linkage stack operations
.Lpcmsk:.quad 0x0000000180000000
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
.L4malign:.quad 0xffffffffffc00000
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
.Lscan2g:.quad 0x80000000 + 0x20000 - 8 # 2GB + 128K - 8
.Lnop: .long 0x07000700
[S390] head.S code moving. There is almost no room left for any new code between 0x10000 and 0x10480. Move the code from 0x10000 to 0x11000. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-29 12:58:17 +00:00
.Lparmaddr:
.quad PARMAREA
[S390] Fixed handling of access register mode faults. Replaced check_user_space() + __check_access_register with the new check_space(). The old functions made wrong assumptions about kernel and user space when the kernel and user address spaces are switched (kernel in home space, user in primary/secondary space). Secondly the user process can switch to the accress register mode if it is running in primary or secondary mode. In addition it can load an arbitrary value to the access registers. If any other value than 0 for primary space or 1 for secondary space is loaded and memory is accessed using the base register related to the access register, the program should be terminated with a SIGSEGV. To achieve that the DUALD pointer in the DUCT and the PSALD pointer in the PASTE need to point to an array of 8 invalid access-list entries to get a ALEN-translation exception if an invalid alet is used. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-03-05 22:35:54 +00:00
.align 64
.Lduct: .long 0,0,0,0,.Lduald,0,0,0
.long 0,0,0,0,0,0,0,0
.align 128
.Lduald:.rept 8
.long 0x80000000,0,0,0 # invalid access-list entries
.endr
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
[S390] fix s390 assembler code alignments The alignment is missing for various global symbols in s390 assembly code. With a recent gcc and an instruction like stgrl this can lead to a specification exception if the instruction uses such a mis-aligned address. Specify the alignment explicitely and while add it define __ALIGN for s390 and use the ENTRY define to save some lines of code. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 08:48:19 +00:00
ENTRY(_ehead)
[S390] add support for compressed kernels Add the "bzImage" compile target and the necessary code to generate compressed kernel images. The old style uncompressed "image" target is preserved, a simple make will build them both. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 21:37:53 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#ifdef CONFIG_SHARED_KERNEL
[S390] correct address of _stext with CONFIG_SHARED_KERNEL=y As of git commit 1844c9bc0b2fed3023551c1affe033ab38e90b9a head64.S/head31.S are not included in head.S anymore but build as an extra object. This breaks shared kernel support because the .org statement in head64.S/head31.S for CONFIG_SHARED_KERNEL=y will have a different effect. The end address of the head.text section in head.o will be added to the .org value, to compensate for this subtract 0x11000 to get the required value of 0x100000 again. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-05-12 07:32:13 +00:00
.org 0x100000 - 0x11000 # head.o ends at 0x11000
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#endif
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#
[S390] head.S code moving. There is almost no room left for any new code between 0x10000 and 0x10480. Move the code from 0x10000 to 0x11000. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-06-29 12:58:17 +00:00
# startup-code, running in absolute addressing mode
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#
[S390] fix s390 assembler code alignments The alignment is missing for various global symbols in s390 assembly code. With a recent gcc and an instruction like stgrl this can lead to a specification exception if the instruction uses such a mis-aligned address. Specify the alignment explicitely and while add it define __ALIGN for s390 and use the ENTRY define to save some lines of code. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 08:48:19 +00:00
ENTRY(_stext)
basr %r13,0 # get base
[PATCH] s390: export ipl device parameters Sysfs interface to export ipl device parameters. Dependent on the ipl type the interface will look like this: - ccw ipl: /sys/firmware/ipl/device /ipl_type - fcp ipl: /sys/firmware/ipl/binary_parameter /bootprog /br_lba /device /ipl_type /lun /scp_data /wwpn - otherwise (unknown that is): /sys/firmware/ipl/ipl_type Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 23:00:11 +00:00
.LPG3:
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
# check control registers
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
stctg %c0,%c15,0(%r15)
[S390] smp: external call vs. emergency signal Use a sigp sense running to decide which signal processor order to use for an ipi. If the target cpu is running use external call, if the target cpu is not running use emergency signal. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-10-30 14:16:58 +00:00
oi 6(%r15),0x60 # enable sigp emergency & external call
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
oi 4(%r15),0x10 # switch on low address proctection
lctlg %c0,%c15,0(%r15)
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
lam 0,15,.Laregs-.LPG3(%r13) # load acrs needed by uaccess
brasl %r14,start_kernel # go to C code
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
2005-04-16 22:20:36 +00:00
#
# We returned from start_kernel ?!? PANIK
#
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
basr %r13,0
lpswe .Ldw-.(%r13) # load disabled wait psw
[S390] convert some assembler to C. Convert GET_IPL_DEVICE assembler macro to C function. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-20 13:59:15 +00:00
[S390] Whitespace cleanup. Huge s390 assembly files whitespace cleanup. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2006-09-28 14:56:37 +00:00
.align 8
.Ldw: .quad 0x0002000180000000,0x0000000000000000
.Laregs:.long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
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