linux/arch/s390/boot/head.S

339 lines
8.5 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>
*
* There are 5 different IPL methods
* 1) load the image directly into ram at address 0 and do an PSW restart
* 2) linload will load the image from address 0x10000 to memory 0x10000
* and start the code thru LPSW 0x0008000080010000 (VM only, deprecated)
* 3) generate the tape ipl header, store the generated image on a tape
* and ipl from it
* In case of SL tape you need to IPL 5 times to get past VOL1 etc
* 4) generate the vm reader ipl header, move the generated image to the
* VM reader (use option NOH!) and do a ipl from reader (VM only)
* 5) direct call of start by the SALIPL loader
* We use the cpuid to distinguish between VM and native ipl
* params for kernel are pushed to 0x10400 (see setup.h)
*
*/
#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#define ARCH_OFFSET 4
__HEAD
#define IPL_BS 0x730
.org 0
.long 0x00080000,0x80000000+iplstart # The first 24 bytes are loaded
.long 0x02000018,0x60000050 # by ipl to addresses 0-23.
.long 0x02000068,0x60000050 # (a PSW and two CCWs).
.fill 80-24,1,0x40 # bytes 24-79 are discarded !!
.long 0x020000f0,0x60000050 # The next 160 byte are loaded
.long 0x02000140,0x60000050 # to addresses 0x18-0xb7
.long 0x02000190,0x60000050 # They form the continuation
.long 0x020001e0,0x60000050 # of the CCW program started
.long 0x02000230,0x60000050 # by ipl and load the range
.long 0x02000280,0x60000050 # 0x0f0-0x730 from the image
.long 0x020002d0,0x60000050 # to the range 0x0f0-0x730
.long 0x02000320,0x60000050 # in memory. At the end of
.long 0x02000370,0x60000050 # the channel program the PSW
.long 0x020003c0,0x60000050 # at location 0 is loaded.
.long 0x02000410,0x60000050 # Initial processing starts
.long 0x02000460,0x60000050 # at 0x200 = iplstart.
.long 0x020004b0,0x60000050
.long 0x02000500,0x60000050
.long 0x02000550,0x60000050
.long 0x020005a0,0x60000050
.long 0x020005f0,0x60000050
.long 0x02000640,0x60000050
.long 0x02000690,0x60000050
.long 0x020006e0,0x20000050
.org 0x1a0
.quad 0,iplstart
.org 0x200
#
# subroutine to wait for end I/O
#
.Lirqwait:
mvc __LC_IO_NEW_PSW(16),.Lnewpsw # set up IO interrupt psw
lpsw .Lwaitpsw
.Lioint:
br %r14
.align 8
.Lnewpsw:
.quad 0x0000000080000000,.Lioint
.Lwaitpsw:
.long 0x020a0000,0x80000000+.Lioint
#
# subroutine for loading cards from the reader
#
.Lloader:
la %r4,0(%r14)
la %r3,.Lorb # r2 = address of orb into r2
la %r5,.Lirb # r4 = address of irb
la %r6,.Lccws
la %r7,20
.Linit:
st %r2,4(%r6) # initialize CCW data addresses
la %r2,0x50(%r2)
la %r6,8(%r6)
bct 7,.Linit
lctl %c6,%c6,.Lcr6 # set IO subclass mask
slr %r2,%r2
.Lldlp:
ssch 0(%r3) # load chunk of 1600 bytes
bnz .Llderr
.Lwait4irq:
bas %r14,.Lirqwait
c %r1,__LC_SUBCHANNEL_ID # compare subchannel number
bne .Lwait4irq
tsch 0(%r5)
slr %r0,%r0
ic %r0,8(%r5) # get device status
chi %r0,8 # channel end ?
be .Lcont
chi %r0,12 # channel end + device end ?
be .Lcont
l %r0,4(%r5)
s %r0,8(%r3) # r0/8 = number of ccws executed
mhi %r0,10 # *10 = number of bytes in ccws
lh %r3,10(%r5) # get residual count
sr %r0,%r3 # #ccws*80-residual=#bytes read
ar %r2,%r0
br %r4 # r2 contains the total size
.Lcont:
ahi %r2,0x640 # add 0x640 to total size
la %r6,.Lccws
la %r7,20
.Lincr:
l %r0,4(%r6) # update CCW data addresses
ahi %r0,0x640
st %r0,4(%r6)
ahi %r6,8
bct 7,.Lincr
b .Lldlp
.Llderr:
lpsw .Lcrash
.align 8
.Lorb: .long 0x00000000,0x0080ff00,.Lccws
.Lirb: .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
.Lcr6: .long 0xff000000
.Lloadp:.long 0,0
.align 8
.Lcrash:.long 0x000a0000,0x00000000
.align 8
.Lccws: .rept 19
.long 0x02600050,0x00000000
.endr
.long 0x02200050,0x00000000
iplstart:
mvi __LC_AR_MODE_ID,1 # set esame flag
slr %r0,%r0 # set cpuid to zero
lhi %r1,2 # mode 2 = esame (dump)
sigp %r1,%r0,0x12 # switch to esame mode
bras %r13,0f
.fill 16,4,0x0
0: lmh %r0,%r15,0(%r13) # clear high-order half of gprs
sam31 # switch to 31 bit addressing mode
lh %r1,__LC_SUBCHANNEL_ID # test if subchannel number
bct %r1,.Lnoload # is valid
l %r1,__LC_SUBCHANNEL_ID # load ipl subchannel number
la %r2,IPL_BS # load start address
bas %r14,.Lloader # load rest of ipl image
l %r12,.Lparm # pointer to parameter area
st %r1,IPL_DEVICE+ARCH_OFFSET-PARMAREA(%r12) # save ipl device number
#
# load parameter file from ipl device
#
.Lagain1:
l %r2,.Linitrd # ramdisk loc. is temp
bas %r14,.Lloader # load parameter file
ltr %r2,%r2 # got anything ?
bz .Lnopf
chi %r2,895
bnh .Lnotrunc
la %r2,895
.Lnotrunc:
l %r4,.Linitrd
clc 0(3,%r4),.L_hdr # if it is HDRx
bz .Lagain1 # skip dataset header
clc 0(3,%r4),.L_eof # if it is EOFx
bz .Lagain1 # skip dateset trailer
la %r5,0(%r4,%r2)
lr %r3,%r2
la %r3,COMMAND_LINE-PARMAREA(%r12) # load adr. of command line
mvc 0(256,%r3),0(%r4)
mvc 256(256,%r3),256(%r4)
mvc 512(256,%r3),512(%r4)
mvc 768(122,%r3),768(%r4)
slr %r0,%r0
b .Lcntlp
.Ldelspc:
ic %r0,0(%r2,%r3)
chi %r0,0x20 # is it a space ?
be .Lcntlp
ahi %r2,1
b .Leolp
.Lcntlp:
brct %r2,.Ldelspc
.Leolp:
slr %r0,%r0
stc %r0,0(%r2,%r3) # terminate buffer
.Lnopf:
#
# load ramdisk from ipl device
#
.Lagain2:
l %r2,.Linitrd # addr of ramdisk
st %r2,INITRD_START+ARCH_OFFSET-PARMAREA(%r12)
bas %r14,.Lloader # load ramdisk
st %r2,INITRD_SIZE+ARCH_OFFSET-PARMAREA(%r12) # store size of rd
ltr %r2,%r2
bnz .Lrdcont
st %r2,INITRD_START+ARCH_OFFSET-PARMAREA(%r12) # no ramdisk found
.Lrdcont:
l %r2,.Linitrd
clc 0(3,%r2),.L_hdr # skip HDRx and EOFx
bz .Lagain2
clc 0(3,%r2),.L_eof
bz .Lagain2
#
# reset files in VM reader
#
stidp .Lcpuid # store cpuid
tm .Lcpuid,0xff # running VM ?
bno .Lnoreset
la %r2,.Lreset
lhi %r3,26
diag %r2,%r3,8
la %r5,.Lirb
stsch 0(%r5) # check if irq is pending
tm 30(%r5),0x0f # by verifying if any of the
bnz .Lwaitforirq # activity or status control
tm 31(%r5),0xff # bits is set in the schib
bz .Lnoreset
.Lwaitforirq:
bas %r14,.Lirqwait # wait for IO interrupt
c %r1,__LC_SUBCHANNEL_ID # compare subchannel number
bne .Lwaitforirq
la %r5,.Lirb
tsch 0(%r5)
.Lnoreset:
b .Lnoload
#
# everything loaded, go for it
#
.Lnoload:
l %r1,.Lstartup
br %r1
.Linitrd:.long _end # default address of initrd
.Lparm: .long PARMAREA
.Lstartup: .long startup
.Lreset:.byte 0xc3,0xc8,0xc1,0xd5,0xc7,0xc5,0x40,0xd9,0xc4,0xd9,0x40
.byte 0xc1,0xd3,0xd3,0x40,0xd2,0xc5,0xc5,0xd7,0x40,0xd5,0xd6
.byte 0xc8,0xd6,0xd3,0xc4 # "change rdr all keep nohold"
.L_eof: .long 0xc5d6c600 /* C'EOF' */
.L_hdr: .long 0xc8c4d900 /* C'HDR' */
.align 8
.Lcpuid:.fill 8,1,0
#
# startup-code at 0x10000, running in absolute addressing mode
# this is called either by the ipl loader or directly by PSW restart
# or linload or SALIPL
#
.org 0x10000
ENTRY(startup)
j .Lep_startup_normal
.org EP_OFFSET
#
# This is a list of s390 kernel entry points. At address 0x1000f the number of
# valid entry points is stored.
#
# IMPORTANT: Do not change this table, it is s390 kernel ABI!
#
.ascii EP_STRING
.byte 0x00,0x01
#
# kdump startup-code at 0x10010, running in 64 bit absolute addressing mode
#
.org 0x10010
ENTRY(startup_kdump)
j .Lep_startup_kdump
.Lep_startup_normal:
mvi __LC_AR_MODE_ID,1 # set esame flag
slr %r0,%r0 # set cpuid to zero
lhi %r1,2 # mode 2 = esame (dump)
sigp %r1,%r0,0x12 # switch to esame mode
bras %r13,0f
.fill 16,4,0x0
0: lmh %r0,%r15,0(%r13) # clear high-order half of gprs
sam64 # switch to 64 bit addressing mode
basr %r13,0 # get base
.LPG0:
xc 0x200(256),0x200 # partially clear lowcore
xc 0x300(256),0x300
xc 0xe00(256),0xe00
xc 0xf00(256),0xf00
lctlg %c0,%c15,0x200(%r0) # initialize control registers
stcke __LC_BOOT_CLOCK
mvc __LC_LAST_UPDATE_CLOCK(8),__LC_BOOT_CLOCK+1
spt 6f-.LPG0(%r13)
mvc __LC_LAST_UPDATE_TIMER(8),6f-.LPG0(%r13)
l %r15,.Lstack-.LPG0(%r13)
brasl %r14,verify_facilities
brasl %r14,startup_kernel
.Lstack:
.long 0x8000 + (1<<(PAGE_SHIFT+BOOT_STACK_ORDER)) - STACK_FRAME_OVERHEAD
.align 8
6: .long 0x7fffffff,0xffffffff
#include "head_kdump.S"
#
# params at 10400 (setup.h)
#
.org PARMAREA
.long 0,0 # IPL_DEVICE
.long 0,0 # INITRD_START
.long 0,0 # INITRD_SIZE
.long 0,0 # OLDMEM_BASE
.long 0,0 # OLDMEM_SIZE
.org COMMAND_LINE
.byte "root=/dev/ram0 ro"
.byte 0
.org 0x11000