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linux-next/arch/s390/kernel/head64.S
Martin Schwidefsky 951f22d5b1 [PATCH] s390: spin lock retry
Split spin lock and r/w lock implementation into a single try which is done
inline and an out of line function that repeatedly tries to get the lock
before doing the cpu_relax().  Add a system control to set the number of
retries before a cpu is yielded.

The reason for the spin lock retry is that the diagnose 0x44 that is used to
give up the virtual cpu is quite expensive.  For spin locks that are held only
for a short period of time the costs of the diagnoses outweights the savings
for spin locks that are held for a longer timer.  The default retry count is
1000.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:26:04 -07:00

782 lines
25 KiB
ArmAsm

/*
* arch/s390/kernel/head.S
*
* S390 version
* Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Hartmut Penner (hp@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com),
* Rob van der Heij (rvdhei@iae.nl)
*
* 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)
Changes:
Okt 25 2000 <rvdheij@iae.nl>
added code to skip HDR and EOF to allow SL tape IPL (5 retries)
changed first CCW from rewind to backspace block
*/
#include <linux/config.h>
#include <asm/setup.h>
#include <asm/lowcore.h>
#include <asm/offsets.h>
#include <asm/thread_info.h>
#include <asm/page.h>
#ifndef CONFIG_IPL
.org 0
.long 0x00080000,0x80000000+startup # Just a restart PSW
#else
#ifdef CONFIG_IPL_TAPE
#define IPL_BS 1024
.org 0
.long 0x00080000,0x80000000+iplstart # The first 24 bytes are loaded
.long 0x27000000,0x60000001 # by ipl to addresses 0-23.
.long 0x02000000,0x20000000+IPL_BS # (a PSW and two CCWs).
.long 0x00000000,0x00000000 # external old psw
.long 0x00000000,0x00000000 # svc old psw
.long 0x00000000,0x00000000 # program check old psw
.long 0x00000000,0x00000000 # machine check old psw
.long 0x00000000,0x00000000 # io old psw
.long 0x00000000,0x00000000
.long 0x00000000,0x00000000
.long 0x00000000,0x00000000
.long 0x000a0000,0x00000058 # external new psw
.long 0x000a0000,0x00000060 # svc new psw
.long 0x000a0000,0x00000068 # program check new psw
.long 0x000a0000,0x00000070 # machine check new psw
.long 0x00080000,0x80000000+.Lioint # io new psw
.org 0x100
#
# subroutine for loading from tape
# Paramters:
# R1 = device number
# R2 = load address
.Lloader:
st %r14,.Lldret
la %r3,.Lorbread # r3 = address of orb
la %r5,.Lirb # r5 = address of irb
st %r2,.Lccwread+4 # initialize CCW data addresses
lctl %c6,%c6,.Lcr6
slr %r2,%r2
.Lldlp:
la %r6,3 # 3 retries
.Lssch:
ssch 0(%r3) # load chunk of IPL_BS bytes
bnz .Llderr
.Lw4end:
bas %r14,.Lwait4io
tm 8(%r5),0x82 # do we have a problem ?
bnz .Lrecov
slr %r7,%r7
icm %r7,3,10(%r5) # get residual count
lcr %r7,%r7
la %r7,IPL_BS(%r7) # IPL_BS-residual=#bytes read
ar %r2,%r7 # add to total size
tm 8(%r5),0x01 # found a tape mark ?
bnz .Ldone
l %r0,.Lccwread+4 # update CCW data addresses
ar %r0,%r7
st %r0,.Lccwread+4
b .Lldlp
.Ldone:
l %r14,.Lldret
br %r14 # r2 contains the total size
.Lrecov:
bas %r14,.Lsense # do the sensing
bct %r6,.Lssch # dec. retry count & branch
b .Llderr
#
# Sense subroutine
#
.Lsense:
st %r14,.Lsnsret
la %r7,.Lorbsense
ssch 0(%r7) # start sense command
bnz .Llderr
bas %r14,.Lwait4io
l %r14,.Lsnsret
tm 8(%r5),0x82 # do we have a problem ?
bnz .Llderr
br %r14
#
# Wait for interrupt subroutine
#
.Lwait4io:
lpsw .Lwaitpsw
.Lioint:
c %r1,0xb8 # compare subchannel number
bne .Lwait4io
tsch 0(%r5)
slr %r0,%r0
tm 8(%r5),0x82 # do we have a problem ?
bnz .Lwtexit
tm 8(%r5),0x04 # got device end ?
bz .Lwait4io
.Lwtexit:
br %r14
.Llderr:
lpsw .Lcrash
.align 8
.Lorbread:
.long 0x00000000,0x0080ff00,.Lccwread
.align 8
.Lorbsense:
.long 0x00000000,0x0080ff00,.Lccwsense
.align 8
.Lccwread:
.long 0x02200000+IPL_BS,0x00000000
.Lccwsense:
.long 0x04200001,0x00000000
.Lwaitpsw:
.long 0x020a0000,0x80000000+.Lioint
.Lirb: .long 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
.Lcr6: .long 0xff000000
.align 8
.Lcrash:.long 0x000a0000,0x00000000
.Lldret:.long 0
.Lsnsret: .long 0
#endif /* CONFIG_IPL_TAPE */
#ifdef CONFIG_IPL_VM
#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 0xf0 = 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 0xf0
#
# subroutine for loading cards from the reader
#
.Lloader:
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:
mvc 0x78(8),.Lnewpsw # set up IO interrupt psw
lpsw .Lwaitpsw
.Lioint:
c %r1,0xb8 # 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 %r14 # 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
.Lnewpsw:
.long 0x00080000,0x80000000+.Lioint
.Lwaitpsw:
.long 0x020a0000,0x80000000+.Lioint
.align 8
.Lccws: .rept 19
.long 0x02600050,0x00000000
.endr
.long 0x02200050,0x00000000
#endif /* CONFIG_IPL_VM */
iplstart:
lh %r1,0xb8 # test if subchannel number
bct %r1,.Lnoload # is valid
l %r1,0xb8 # load ipl subchannel number
la %r2,IPL_BS # load start address
bas %r14,.Lloader # load rest of ipl image
larl %r12,_pstart # pointer to parameter area
st %r1,IPL_DEVICE+4-PARMAREA(%r12) # store ipl device number
#
# load parameter file from ipl device
#
.Lagain1:
l %r2,INITRD_START+4-PARMAREA(%r12)# use ramdisk location as 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,INITRD_START+4-PARMAREA(%r12)
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
.Lidebc:
tm 0(%r5),0x80 # high order bit set ?
bo .Ldocv # yes -> convert from EBCDIC
ahi %r5,-1
bct %r3,.Lidebc
b .Lnocv
.Ldocv:
l %r3,.Lcvtab
tr 0(256,%r4),0(%r3) # convert parameters to ascii
tr 256(256,%r4),0(%r3)
tr 512(256,%r4),0(%r3)
tr 768(122,%r4),0(%r3)
.Lnocv: 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,INITRD_START+4-PARMAREA(%r12)# load adr. of ramdisk
bas %r14,.Lloader # load ramdisk
st %r2,INITRD_SIZE+4-PARMAREA(%r12) # store size of ramdisk
ltr %r2,%r2
bnz .Lrdcont
st %r2,INITRD_START+4-PARMAREA(%r12)# no ramdisk found, null it
.Lrdcont:
l %r2,INITRD_START+4-PARMAREA(%r12)
clc 0(3,%r2),.L_hdr # skip HDRx and EOFx
bz .Lagain2
clc 0(3,%r2),.L_eof
bz .Lagain2
#ifdef CONFIG_IPL_VM
#
# reset files in VM reader
#
stidp __LC_CPUID # store cpuid
tm __LC_CPUID,0xff # running VM ?
bno .Lnoreset
la %r2,.Lreset
lhi %r3,26
diag %r2,%r3,8
mvc 0x78(8),.Lrdrnewpsw # set up IO interrupt psw
.Lwaitrdrirq:
lpsw .Lrdrwaitpsw
.Lrdrint:
c %r1,0xb8 # compare subchannel number
bne .Lwaitrdrirq
la %r5,.Lirb
tsch 0(%r5)
.Lnoreset:
b .Lnoload
.align 8
.Lrdrnewpsw:
.long 0x00080000,0x80000000+.Lrdrint
.Lrdrwaitpsw:
.long 0x020a0000,0x80000000+.Lrdrint
#endif
#
# everything loaded, go for it
#
.Lnoload:
l %r1,.Lstartup
br %r1
.Lstartup: .long startup
.Lcvtab:.long _ebcasc # ebcdic to ascii table
.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' */
#endif /* CONFIG_IPL */
#
# SALIPL loader support. Based on a patch by Rob van der Heij.
# This entry point is called directly from the SALIPL loader and
# doesn't need a builtin ipl record.
#
.org 0x800
.globl start
start:
stm %r0,%r15,0x07b0 # store registers
basr %r12,%r0
.base:
l %r11,.parm
l %r8,.cmd # pointer to command buffer
ltr %r9,%r9 # do we have SALIPL parameters?
bp .sk8x8
mvc 0(64,%r8),0x00b0 # copy saved registers
xc 64(240-64,%r8),0(%r8) # remainder of buffer
tr 0(64,%r8),.lowcase
b .gotr
.sk8x8:
mvc 0(240,%r8),0(%r9) # copy iplparms into buffer
.gotr:
l %r10,.tbl # EBCDIC to ASCII table
tr 0(240,%r8),0(%r10)
stidp __LC_CPUID # Are we running on VM maybe
cli __LC_CPUID,0xff
bnz .test
.long 0x83300060 # diag 3,0,x'0060' - storage size
b .done
.test:
mvc 0x68(8),.pgmnw # set up pgm check handler
l %r2,.fourmeg
lr %r3,%r2
bctr %r3,%r0 # 4M-1
.loop: iske %r0,%r3
ar %r3,%r2
.pgmx:
sr %r3,%r2
la %r3,1(%r3)
.done:
l %r1,.memsize
st %r3,4(%r1)
slr %r0,%r0
st %r0,INITRD_SIZE+4-PARMAREA(%r11)
st %r0,INITRD_START+4-PARMAREA(%r11)
j startup # continue with startup
.tbl: .long _ebcasc # translate table
.cmd: .long COMMAND_LINE # address of command line buffer
.parm: .long PARMAREA
.fourmeg: .long 0x00400000 # 4M
.pgmnw: .long 0x00080000,.pgmx
.memsize: .long memory_size
.lowcase:
.byte 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07
.byte 0x08,0x09,0x0a,0x0b,0x0c,0x0d,0x0e,0x0f
.byte 0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17
.byte 0x18,0x19,0x1a,0x1b,0x1c,0x1d,0x1e,0x1f
.byte 0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27
.byte 0x28,0x29,0x2a,0x2b,0x2c,0x2d,0x2e,0x2f
.byte 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37
.byte 0x38,0x39,0x3a,0x3b,0x3c,0x3d,0x3e,0x3f
.byte 0x40,0x41,0x42,0x43,0x44,0x45,0x46,0x47
.byte 0x48,0x49,0x4a,0x4b,0x4c,0x4d,0x4e,0x4f
.byte 0x50,0x51,0x52,0x53,0x54,0x55,0x56,0x57
.byte 0x58,0x59,0x5a,0x5b,0x5c,0x5d,0x5e,0x5f
.byte 0x60,0x61,0x62,0x63,0x64,0x65,0x66,0x67
.byte 0x68,0x69,0x6a,0x6b,0x6c,0x6d,0x6e,0x6f
.byte 0x70,0x71,0x72,0x73,0x74,0x75,0x76,0x77
.byte 0x78,0x79,0x7a,0x7b,0x7c,0x7d,0x7e,0x7f
.byte 0x80,0x81,0x82,0x83,0x84,0x85,0x86,0x87
.byte 0x88,0x89,0x8a,0x8b,0x8c,0x8d,0x8e,0x8f
.byte 0x90,0x91,0x92,0x93,0x94,0x95,0x96,0x97
.byte 0x98,0x99,0x9a,0x9b,0x9c,0x9d,0x9e,0x9f
.byte 0xa0,0xa1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7
.byte 0xa8,0xa9,0xaa,0xab,0xac,0xad,0xae,0xaf
.byte 0xb0,0xb1,0xb2,0xb3,0xb4,0xb5,0xb6,0xb7
.byte 0xb8,0xb9,0xba,0xbb,0xbc,0xbd,0xbe,0xbf
.byte 0xc0,0x81,0x82,0x83,0x84,0x85,0x86,0x87 # .abcdefg
.byte 0x88,0x89,0xca,0xcb,0xcc,0xcd,0xce,0xcf # hi
.byte 0xd0,0x91,0x92,0x93,0x94,0x95,0x96,0x97 # .jklmnop
.byte 0x98,0x99,0xda,0xdb,0xdc,0xdd,0xde,0xdf # qr
.byte 0xe0,0xe1,0xa2,0xa3,0xa4,0xa5,0xa6,0xa7 # ..stuvwx
.byte 0xa8,0xa9,0xea,0xeb,0xec,0xed,0xee,0xef # yz
.byte 0xf0,0xf1,0xf2,0xf3,0xf4,0xf5,0xf6,0xf7
.byte 0xf8,0xf9,0xfa,0xfb,0xfc,0xfd,0xfe,0xff
#
# startup-code at 0x10000, running in real mode
# this is called either by the ipl loader or directly by PSW restart
# or linload or SALIPL
#
.org 0x10000
startup:basr %r13,0 # get base
.LPG1: sll %r13,1 # remove high order bit
srl %r13,1
lhi %r1,1 # mode 1 = esame
slr %r0,%r0 # set cpuid to zero
sigp %r1,%r0,0x12 # switch to esame mode
sam64 # switch to 64 bit mode
lctlg %c0,%c15,.Lctl-.LPG1(%r13) # load control registers
larl %r12,_pstart # pointer to parameter area
# move IPL device to lowcore
mvc __LC_IPLDEV(4),IPL_DEVICE+4-PARMAREA(%r12)
#
# clear bss memory
#
larl %r2,__bss_start # start of bss segment
larl %r3,_end # end of bss segment
sgr %r3,%r2 # length of bss
sgr %r4,%r4 #
sgr %r5,%r5 # set src,length and pad to zero
mvcle %r2,%r4,0 # clear mem
jo .-4 # branch back, if not finish
l %r2,.Lrcp-.LPG1(%r13) # Read SCP forced command word
.Lservicecall:
stosm .Lpmask-.LPG1(%r13),0x01 # authorize ext interrupts
stctg %r0,%r0,.Lcr-.LPG1(%r13) # get cr0
la %r1,0x200 # set bit 22
og %r1,.Lcr-.LPG1(%r13) # or old cr0 with r1
stg %r1,.Lcr-.LPG1(%r13)
lctlg %r0,%r0,.Lcr-.LPG1(%r13) # load modified cr0
mvc __LC_EXT_NEW_PSW(8),.Lpcmsk-.LPG1(%r13) # set postcall psw
larl %r1,.Lsclph
stg %r1,__LC_EXT_NEW_PSW+8 # set handler
larl %r4,_pstart # %r4 is our index for sccb stuff
la %r1,.Lsccb-PARMAREA(%r4) # our sccb
.insn rre,0xb2200000,%r2,%r1 # service call
ipm %r1
srl %r1,28 # get cc code
xr %r3,%r3
chi %r1,3
be .Lfchunk-.LPG1(%r13) # leave
chi %r1,2
be .Lservicecall-.LPG1(%r13)
lpsw .Lwaitsclp-.LPG1(%r13)
.Lsclph:
lh %r1,.Lsccbr-PARMAREA(%r4)
chi %r1,0x10 # 0x0010 is the sucess code
je .Lprocsccb # let's process the sccb
chi %r1,0x1f0
bne .Lfchunk-.LPG1(%r13) # unhandled error code
c %r2,.Lrcp-.LPG1(%r13) # Did we try Read SCP forced
bne .Lfchunk-.LPG1(%r13) # if no, give up
l %r2,.Lrcp2-.LPG1(%r13) # try with Read SCP
b .Lservicecall-.LPG1(%r13)
.Lprocsccb:
lghi %r1,0
icm %r1,3,.Lscpincr1-PARMAREA(%r4) # use this one if != 0
jnz .Lscnd
lg %r1,.Lscpincr2-PARMAREA(%r4) # otherwise use this one
.Lscnd:
xr %r3,%r3 # same logic
ic %r3,.Lscpa1-PARMAREA(%r4)
chi %r3,0x00
jne .Lcompmem
l %r3,.Lscpa2-PARMAREA(%r13)
.Lcompmem:
mlgr %r2,%r1 # mem in MB on 128-bit
l %r1,.Lonemb-.LPG1(%r13)
mlgr %r2,%r1 # mem size in bytes in %r3
b .Lfchunk-.LPG1(%r13)
.Lpmask:
.byte 0
.align 8
.Lcr:
.quad 0x00 # place holder for cr0
.Lwaitsclp:
.long 0x020A0000
.quad .Lsclph
.Lrcp:
.int 0x00120001 # Read SCP forced code
.Lrcp2:
.int 0x00020001 # Read SCP code
.Lonemb:
.int 0x100000
.Lfchunk:
# set program check new psw mask
mvc __LC_PGM_NEW_PSW(8),.Lpcmsk-.LPG1(%r13)
#
# find memory chunks.
#
lgr %r9,%r3 # end of mem
larl %r1,.Lchkmem # set program check address
stg %r1,__LC_PGM_NEW_PSW+8
la %r1,1 # test in increments of 128KB
sllg %r1,%r1,17
larl %r3,memory_chunk
slgr %r4,%r4 # set start of chunk to zero
slgr %r5,%r5 # set end of chunk to zero
slr %r6,%r6 # set access code to zero
la %r10,MEMORY_CHUNKS # number of chunks
.Lloop:
tprot 0(%r5),0 # test protection of first byte
ipm %r7
srl %r7,28
clr %r6,%r7 # compare cc with last access code
je .Lsame
j .Lchkmem
.Lsame:
algr %r5,%r1 # add 128KB to end of chunk
# no need to check here,
brc 12,.Lloop # this is the same chunk
.Lchkmem: # > 16EB or tprot got a program check
clgr %r4,%r5 # chunk size > 0?
je .Lchkloop
stg %r4,0(%r3) # store start address of chunk
lgr %r0,%r5
slgr %r0,%r4
stg %r0,8(%r3) # store size of chunk
st %r6,20(%r3) # store type of chunk
la %r3,24(%r3)
larl %r8,memory_size
stg %r5,0(%r8) # store memory size
ahi %r10,-1 # update chunk number
.Lchkloop:
lr %r6,%r7 # set access code to last cc
# we got an exception or we're starting a new
# chunk , we must check if we should
# still try to find valid memory (if we detected
# the amount of available storage), and if we
# have chunks left
lghi %r4,1
sllg %r4,%r4,31
clgr %r5,%r4
je .Lhsaskip
xr %r0, %r0
clgr %r0, %r9 # did we detect memory?
je .Ldonemem # if not, leave
chi %r10, 0 # do we have chunks left?
je .Ldonemem
.Lhsaskip:
algr %r5,%r1 # add 128KB to end of chunk
lgr %r4,%r5 # potential new chunk
clgr %r5,%r9 # should we go on?
jl .Lloop
.Ldonemem:
larl %r12,machine_flags
#
# find out if we are running under VM
#
stidp __LC_CPUID # store cpuid
tm __LC_CPUID,0xff # running under VM ?
bno 0f-.LPG1(%r13)
oi 7(%r12),1 # set VM flag
0: lh %r0,__LC_CPUID+4 # get cpu version
chi %r0,0x7490 # running on a P/390 ?
bne 1f-.LPG1(%r13)
oi 7(%r12),4 # set P/390 flag
1:
#
# find out if we have the MVPG instruction
#
la %r1,0f-.LPG1(%r13) # set program check address
stg %r1,__LC_PGM_NEW_PSW+8
sgr %r0,%r0
lghi %r1,0
lghi %r2,0
mvpg %r1,%r2 # test MVPG instruction
oi 7(%r12),16 # set MVPG flag
0:
#
# find out if the diag 0x44 works in 64 bit mode
#
la %r1,0f-.LPG1(%r13) # set program check address
stg %r1,__LC_PGM_NEW_PSW+8
diag 0,0,0x44 # test diag 0x44
oi 7(%r12),32 # set diag44 flag
0:
#
# find out if we have the IDTE instruction
#
la %r1,0f-.LPG1(%r13) # set program check address
stg %r1,__LC_PGM_NEW_PSW+8
.long 0xb2b10000 # store facility list
tm 0xc8,0x08 # check bit for clearing-by-ASCE
bno 0f-.LPG1(%r13)
lhi %r1,2094
lhi %r2,0
.long 0xb98e2001
oi 7(%r12),0x80 # set IDTE flag
0:
lpswe .Lentry-.LPG1(13) # jump to _stext in primary-space,
# virtual and never return ...
.align 16
.Lentry:.quad 0x0000000180000000,_stext
.Lctl: .quad 0x04b50002 # cr0: various things
.quad 0 # cr1: primary space segment table
.quad .Lduct # cr2: dispatchable unit control table
.quad 0 # cr3: instruction authorization
.quad 0 # cr4: instruction authorization
.quad 0xffffffffffffffff # 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 0 # cr15: linkage stack operations
.Lpcmsk:.quad 0x0000000180000000
.L4malign:.quad 0xffffffffffc00000
.Lscan2g:.quad 0x80000000 + 0x20000 - 8 # 2GB + 128K - 8
.Lnop: .long 0x07000700
.org PARMAREA-64
.Lduct: .long 0,0,0,0,0,0,0,0
.long 0,0,0,0,0,0,0,0
#
# params at 10400 (setup.h)
#
.org PARMAREA
.global _pstart
_pstart:
.quad 0 # IPL_DEVICE
.quad RAMDISK_ORIGIN # INITRD_START
.quad RAMDISK_SIZE # INITRD_SIZE
.org COMMAND_LINE
.byte "root=/dev/ram0 ro"
.byte 0
.org 0x11000
.Lsccb:
.hword 0x1000 # length, one page
.byte 0x00,0x00,0x00
.byte 0x80 # variable response bit set
.Lsccbr:
.hword 0x00 # response code
.Lscpincr1:
.hword 0x00
.Lscpa1:
.byte 0x00
.fill 89,1,0
.Lscpa2:
.int 0x00
.Lscpincr2:
.quad 0x00
.fill 3984,1,0
.org 0x12000
.global _pend
_pend:
#ifdef CONFIG_SHARED_KERNEL
.org 0x100000
#endif
#
# startup-code, running in virtual mode
#
.globl _stext
_stext: basr %r13,0 # get base
.LPG2:
#
# Setup stack
#
larl %r15,init_thread_union
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
xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) # clear backchain
# check control registers
stctg %c0,%c15,0(%r15)
oi 6(%r15),0x20 # enable sigp external interrupts
oi 4(%r15),0x10 # switch on low address proctection
lctlg %c0,%c15,0(%r15)
#
lam 0,15,.Laregs-.LPG2(%r13) # load access regs 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