patch-2.3.99-pre8 linux/arch/s390/kernel/head.S

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diff -u --recursive --new-file v2.3.99-pre7/linux/arch/s390/kernel/head.S linux/arch/s390/kernel/head.S
@@ -0,0 +1,668 @@
+/*
+ *  arch/s390/kernel/head.S
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Hartmut Penner (hp@de.ibm.com),
+ *               Martin Schwidefsky (schwidefsky@de.ibm.com),
+ *
+ * There are 4 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
+ *  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)
+ *  We use the cpuid to distinguish between VM and native ipl
+ *  params for kernel are pushed to 0x10400 (see setup.h)
+ */
+
+#include <linux/config.h>
+#include <asm/setup.h>
+#include <asm/lowcore.h>
+
+#ifndef CONFIG_IPL
+        .org   0
+        .long  0x00080000,0x80000000+iplstart  # Just a restart PSW
+
+iplstart:
+        l     %r12,.Lparm                      # pointer to parameter area
+#
+# find out memory size
+#
+        mvc   104(8,0),.Lpcmem0          # setup program check handler
+        slr   %r2,%r2
+        lhi   %r3,1
+        sll   %r3,20
+.Lloop0:
+        l     %r0,0(%r2)                 # test page
+        ar    %r2,%r3                    # add 1M
+        jnm   .Lloop0                    # r1 < 0x80000000 -> loop
+.Lchkmem0:
+        n     %r2,.L4malign0             # align to multiples of 4M
+        st    %r2,MEMORY_SIZE-PARMAREA(%r12)  # store memory size
+        slr   %r2,%r2
+        st    %r2,INITRD_SIZE-PARMAREA(%r12)  # null ramdisk
+        st    %r2,INITRD_START-PARMAREA(%r12)
+        j     start
+
+.Lparm: .long  PARMAREA
+.L4malign0:.long 0xffc00000
+        .align 8
+.Lpcmem0:.long  0x00080000,0x80000000 + .Lchkmem0
+
+#else
+#ifdef CONFIG_IPL_TAPE
+#define IPL_BS 1024
+        .org   0
+        .long  0x00080000,0x80000000+iplstart  # The first 24 bytes are loaded
+        .long  0x07000000,0x60000001           # 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
+iplstart:
+	l     %r1,0xb8                         # load ipl subchannel number
+        lhi   %r2,IPL_BS                       # load start address
+        bras  %r14,.Lloader                    # load rest of ipl image
+        st    %r1,__LC_IPLDEV                  # store ipl device number
+        l     %r12,.Lparm                      # pointer to parameter area
+
+#
+# find out memory size
+#
+        mvc   104(8,0),.Lpcmem0          # setup program check handler
+        slr   %r2,%r2
+        lhi   %r3,1
+        sll   %r3,20
+.Lloop0:
+        l     %r0,0(%r2)                 # test page
+        ar    %r2,%r3                    # add 1M
+        jnm   .Lloop0                    # r1 < 0x80000000 -> loop
+.Lchkmem0:
+        n     %r2,.L4malign0             # align to multiples of 4M
+        st    %r2,MEMORY_SIZE-PARMAREA(%r12)  # store memory size
+        c     %r2,.Lbigmem               # more than 64 MB of memory ?
+        jl    .Lmemok                    # if yes load ramdisk to 32 MB
+        mvc   INITRD_START-PARMAREA(4,%r12),.Lrdstart
+.Lmemok:
+
+#
+# load parameter file from tape
+#
+ 	l     %r2,INITRD_START-PARMAREA(%r12)  # use ramdisk location as temp
+        bras  %r14,.Lloader                    # load parameter file
+        ltr   %r2,%r2                          # got anything ?
+        jz    .Lnopf
+	chi   %r2,895
+	jnh   .Lnotrunc
+	lhi   %r2,895
+.Lnotrunc:
+        l     %r4,INITRD_START-PARMAREA(%r12)
+        la    %r5,0(%r4,%r2)
+        lr    %r3,%r2
+.Lidebc:
+        tm    0(%r5),0x80                      # high order bit set ?
+        jo    .Ldocv                           #  yes -> convert from EBCDIC
+        ahi   %r5,-1
+        brct  %r3,.Lidebc
+        j     .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
+        j     .Lcntlp
+.Ldelspc:
+        ic    %r0,0(%r2,%r3)
+        chi   %r0,0x20                         # is it a space ?
+        je    .Lcntlp
+        ahi   %r2,1
+        j     .Leolp
+.Lcntlp:
+        brct  %r2,.Ldelspc
+.Leolp:
+        slr   %r0,%r0
+        stc   %r0,0(%r2,%r3)                   # terminate buffer
+.Lnopf:
+
+#
+# load ramdisk from tape
+#	
+ 	l     %r2,INITRD_START-PARMAREA(%r12)  # load adr. of ramdisk
+        bras  %r14,.Lloader                    # load ramdisk
+ 	st    %r2,INITRD_SIZE-PARMAREA(%r12)   # store size of ramdisk
+        ltr   %r2,%r2
+        jnz   .Lrdcont
+        st    %r2,INITRD_START-PARMAREA(%r12)  # no ramdisk found, null it
+.Lrdcont:
+#
+# everything loaded, go for it
+#
+        j     start
+#
+# 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:
+        lhi   %r6,3                            # 3 retries
+.Lssch:
+        ssch  0(%r3)                           # load chunk of IPL_BS bytes
+        jnz   .Llderr
+.Lw4end:
+        bras  %r14,.Lwait4io
+        tm    8(%r5),0x82                      # do we have a problem ?
+        jnz   .Lrecov
+        slr   %r7,%r7
+        icm   %r7,3,10(%r5)                    # get residual count
+        lcr   %r7,%r7
+        ahi   %r7,IPL_BS                       # IPL_BS-residual=#bytes read
+        ar    %r2,%r7                          # add to total size
+        tm    8(%r5),0x01                      # found a tape mark ?
+        jnz   .Ldone
+        l     %r0,.Lccwread+4                  # update CCW data addresses
+        ar    %r0,%r7
+        st    %r0,.Lccwread+4                
+        j     .Lldlp
+.Ldone:
+        l     %r14,.Lldret
+        br    %r14                             # r2 contains the total size
+.Lrecov:
+        bras  %r14,.Lsense                     # do the sensing
+        brct  %r6,.Lssch                       # dec. retry count & branch
+        j     .Llderr
+#
+# Sense subroutine
+#
+.Lsense:
+        st    %r14,.Lsnsret
+        la    %r7,.Lorbsense              
+        ssch  0(%r7)                           # start sense command
+        jnz   .Llderr
+        bras  %r14,.Lwait4io
+        l     %r14,.Lsnsret
+        tm    8(%r5),0x82                      # do we have a problem ?
+        jnz   .Llderr
+        br    %r14
+#
+# Wait for interrupt subroutine
+#
+.Lwait4io:
+        lpsw  .Lwaitpsw                 
+.Lioint:
+        c     %r1,0xb8                         # compare subchannel number
+        jne   .Lwait4io
+        tsch  0(%r5)
+        slr   %r0,%r0
+        tm    8(%r5),0x82                      # do we have a problem ?
+        jnz   .Lwtexit
+        tm    8(%r5),0x04                      # got device end ?
+        jz    .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
+.Lpcmem0:.long  0x00080000,0x80000000 + .Lchkmem0
+.Lparm: .long  PARMAREA
+.L4malign0:.long 0xffc00000
+.Lbigmem:.long 0x04000000
+.Lrdstart:.long 0x02000000
+.Lldret:.long  0
+.Lsnsret: .long 0
+.Lcvtab:.long  _ebcasc                         # ebcdic to ascii table
+
+#endif  /* CONFIG_IPL_TAPE */
+
+#ifdef CONFIG_IPL_VM
+        .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
+iplstart:
+	l     %r1,0xb8                         # load ipl subchannel number
+        lhi   %r2,0x730                        # load start address
+        bras  %r14,.Lloader                    # load rest of ipl image
+        st    %r1,__LC_IPLDEV                  # store ipl device number
+	l     %r12,.Lparm                      # pointer to parameter area
+
+#
+# find out memory size
+#
+        mvc   104(8,0),.Lpcmem0           # setup program check handler
+        slr   %r2,%r2
+        lhi   %r3,1
+        sll   %r3,20
+.Lloop0:
+        l     %r0,0(%r2)                 # test page
+        ar    %r2,%r3                    # add 1M
+        jnm   .Lloop0                    # r1 < 0x80000000 -> loop
+.Lchkmem0:
+        n     %r2,.L4malign0             # align to multiples of 4M
+        st    %r2,MEMORY_SIZE-PARMAREA(%r12)  # store memory size
+        c     %r2,.Lbigmem               # more than 64 MB of memory ?
+        jl    .Lmemok                    # if yes load ramdisk to 32 MB
+        mvc   INITRD_START-PARMAREA(4,%r12),.Lrdstart
+.Lmemok:
+
+#
+# load parameter file from reader
+#
+        l     %r2,INITRD_START-PARMAREA(%r12)  # use ramdisk location as temp
+        bras  %r14,.Lloader                    # load parameter file
+        ltr   %r2,%r2                          # got anything ?
+        jz    .Lnopf
+        chi   %r2,895
+        jnh   .Lnotrunc
+        lhi   %r2,895
+.Lnotrunc:
+        l     %r4,INITRD_START-PARMAREA(%r12)
+        la    %r5,0(%r4,%r2)
+        lr    %r3,%r2
+.Lidebc:
+        tm    0(%r5),0x80                      # high order bit set ?
+        jo    .Ldocv                           #  yes -> convert from EBCDIC
+        ahi   %r5,-1
+        brct  %r3,.Lidebc
+        j     .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
+        j     .Lcntlp
+.Ldelspc:
+        ic    %r0,0(%r2,%r3)
+        chi   %r0,0x20                         # is it a space ?
+        je    .Lcntlp
+        ahi   %r2,1
+        j     .Leolp
+.Lcntlp:
+        brct  %r2,.Ldelspc
+.Leolp:
+        slr   %r0,%r0
+        stc   %r0,0(%r2,%r3)                   # terminate buffer
+.Lnopf:
+
+#
+# load ramdisk from reader
+#	
+	l     %r2,INITRD_START-PARMAREA(%r12)  # load adr. of ramdisk
+        bras  %r14,.Lloader                    # load ramdisk
+	st    %r2,INITRD_SIZE-PARMAREA(%r12)   # store size of ramdisk
+        ltr   %r2,%r2
+        jnz   .Lrdcont
+        st    %r2,INITRD_START-PARMAREA(%r12)  # no ramdisk found, null it
+.Lrdcont:
+
+#
+# everything loaded, reset files in reader, then go for it
+#
+        stidp __LC_CPUID                       # store cpuid
+        lh    %r0,__LC_CPUID+4                 # get cpu version
+        chi   %r0,0x7490                       # running on P/390 ?
+        je   start                             #   no -> skip reset
+        la    %r2,.Lreset              
+        lhi   %r3,26
+        .long 0x83230008
+	j     start
+
+#
+# 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
+        ahi   %r2,0x50
+        ahi   %r6,8
+        brct  7,.Linit
+
+        lctl  %c6,%c6,.Lcr6                    # set IO subclass mask
+	slr   %r2,%r2
+.Lldlp:
+        ssch  0(%r3)                           # load chunk of 1600 bytes
+        jnz   .Llderr
+.Lwait4irq:
+        mvc   __LC_IO_NEW_PSW(8),.Lnewpsw      # set up IO interrupt psw
+        lpsw  .Lwaitpsw              
+.Lioint:
+        c     %r1,0xb8                         # compare subchannel number
+	jne   .Lwait4irq
+	tsch  0(%r5)
+
+	slr   %r0,%r0
+	ic    %r0,8(%r5)                       # get device status
+	chi   %r0,8                            # channel end ?
+	je    .Lcont
+	chi   %r0,12                           # channel end + device end ?
+	je    .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
+        brct  7,.Lincr
+
+        j     .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
+.Lparm:	.long  PARMAREA
+.L4malign0:.long 0xffc00000
+.Lbigmem:.long 0x04000000
+.Lrdstart:.long 0x02000000
+.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"
+        .align 8
+.Lpcmem0:.long  0x00080000,0x80000000 + .Lchkmem0
+.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
+	
+        .org   0x730     # end of the area loaded by the ipl channel program
+#endif  /* CONFIG_IPL_VM */
+
+#endif  /* CONFIG_IPL */
+
+#
+# startup-code at 0x10000, running in real mode
+# this is called either by the ipl loader or directly by PSW restart or linload
+#
+        .org  0x10000
+        .globl start
+start:  basr  %r13,0                     # get base
+.LPG1:  lctl  %c1,%c1,.Lpstd-.LPG1(%r13) # load pstd
+        lctl  %c7,%c7,.Lpstd-.LPG1(%r13) # load sstd
+        lctl  %c13,%c13,.Lpstd-.LPG1(%r13) # load hstd
+        lctl  %c0,%c0,.Lcr0-.LPG1(%r13)  # set CR0
+	l     %r12,.Lparm1-.LPG1(%r13)   # pointer to parameter area
+
+#
+# find out memory size. That is done in the ipl loader too but for
+# ipl from dasd the size of the memory has to be detected too...
+#
+        icm   %r0,15,MEMORY_SIZE-PARMAREA(%r12)
+        jnz   .Lsizeok
+	mvc   104(8,0),.Lpcmem-.LPG1(%r13) # setup program check handler
+        slr   %r1,%r1
+        lhi   %r2,1
+        sll   %r2,20
+.Lloop:	
+	l     %r0,0(%r1)                 # test page
+	ar    %r1,%r2                    # add 1M
+	jnm   .Lloop                     # r1 < 0x80000000 -> loop
+.Lchkmem:
+	n     %r1,.L4malign-.LPG1(%r13)  # align to multiples of 4M
+	st    %r1,MEMORY_SIZE-PARMAREA(%r12)  # store memory size
+.Lsizeok:
+
+#
+# find out if we are running under VM
+#
+        stidp  __LC_CPUID               # store cpuid
+	tm     __LC_CPUID,0xff          # running under VM ?
+	jno    .Lnovm
+        oi     MACHINE_FLAGS+3-PARMAREA(%r12),1    # set VM flag
+.Lnovm:
+        lh     %r0,__LC_CPUID+4         # get cpu version
+        chi    %r0,0x7490               # running on a P/390 ?
+        jne    .Lnop390
+        oi     MACHINE_FLAGS+3-PARMAREA(%r12),4    # set P/390 flag
+.Lnop390:
+
+#
+# find out if we have an IEEE fpu
+#
+        mvc    104(8,0),.Lpcfpu-.LPG1(%r13) # setup program check handler
+        ld     %f0,.Lflt0-.LPG1(%r13)   # load (float) 0.0
+        ldr    %f2,%f0
+        adbr   %f0,%f2                  # test IEEE add instruction
+        oi     MACHINE_FLAGS+3-PARMAREA(%r12),2    # set IEEE fpu flag
+.Lchkfpu:
+
+        lpsw  .Lentry-.LPG1(13)         # jump to _stext in primary-space,
+                                        # virtual and never return ...
+        .align 8
+.Lentry:.long  0x04080000,0x80000000 + _stext
+.Lpstd: .long  .Lpgd+0x7F               # segment-table
+.Lcr0:  .long  0x04b50002
+.Lpcmem:.long  0x00080000,0x80000000 + .Lchkmem
+.Lpcfpu:.long  0x00080000,0x80000000 + .Lchkfpu
+.Lflt0: .double 0
+.Lparm1:.long  PARMAREA
+.L4malign:.long 0xffc00000
+
+#
+# params at 10400 (setup.h)
+#
+	.org   PARMAREA
+        .long  0x0100                   # ORIG_ROOT_DEV: ramdisk major/minor
+        .word  0                        # MOUNT_ROOT_RDONLY: no
+	.long  0                        # MEMORY_SIZE
+	.long  0                        # MACHINE_FLAGS (bit 0:VM, bit 1:IEEE)
+        .long  RAMDISK_ORIGIN           # INITRD_START
+        .long  0x800000                 # INITRD_SIZE
+	.word  0                        # RAMDISK_FLAGS
+
+        .org   COMMAND_LINE
+#       .byte  "root=/dev/nfs rw nfsroot=9.164.160.7:/home/mschwide/nfsboot "
+#       .byte  "ip=9.164.147.12:9.164.160.7:9.164.147.1:255.255.255.0:vmlinux:tr0:off"
+#       .byte  "root=/dev/nfs nfsroot=9.164.160.7:/home/mschwide/nfsboot "
+#       .byte  "ip=9.164.181.228:9.164.160.7:9.164.181.1:255.255.224.0:vmlinux:tr0:off"
+#       .byte  "root=/dev/nfs nfsroot=9.164.160.7:/home/pasch/nfsboot "
+#       .byte  "ip=9.164.185.120:9.164.160.7:9.164.181.1:255.255.224.0:vmlinux:tr0:off"
+#       .byte  "mdisk=402:65536:1229,403:131072:2780 root=/dev/mnda ro"
+#       .byte  "root=/dev/nfs rw nfsroot=9.164.160.209:/usr/local/nfsboot "
+#       .byte  "ip=9.164.181.228:9.164.160.209:9.164.181.1:255.255.224.0:vmlinux:tr0:off"
+    	.byte  "root=/dev/ram0 ro"
+#       .byte  0
+
+#
+# startup-code, running in virtual mode
+#
+        .org   0x10800
+        .globl _stext
+_stext:	basr  %r13,0                    # get base
+.LPG2:
+#
+# Setup lowcore
+#
+        l     %r1,__LC_IPLDEV           # load ipl device number
+        spx   .Lprefix-.LPG2(%r13)      # set prefix to linux lowcore
+        st    %r1,__LC_IPLDEV           # store ipl device number
+        l     %r15,.Linittu-.LPG2(%r13)
+        ahi   %r15,8192                 # init_task_union + 8191
+        st    %r15,__LC_KERNEL_STACK    # set end of kernel stack
+        ahi   %r15,-96
+        xc    0(4,%r15),0(%r15)         # set backchain to zero
+        lhi   %r0,-1
+        st    %r0,__LC_KERNEL_LEVEL     # set interrupt count to -1
+#
+# clear bss memory
+#
+        l     %r2,.Lbss_bgn-.LPG2(%r13) # start of bss
+        l     %r3,.Lbss_end-.LPG2(%r13) # end of bss
+        sr    %r3,%r2                   # length of bss
+        sr    %r4,%r4                   #
+        sr    %r5,%r5                   # set src,length and pad to zero
+        sr    %r0,%r0                   #
+        mvcle %r2,%r4,0                 # clear mem
+        jo    .-4                       # branch back, if not finish
+# check control registers
+        stctl  %c0,%c15,0(%r15)
+        oc     2(1,%r15),.Locbits+5-.LPG2(%r13) # enable sigp external ints.
+        oc     0(1,%r15),.Locbits+4-.LPG2(%r13) # low addresss proctection
+        lctl   %c0,%c15,0(%r15)
+
+#
+        lam    0,15,.Laregs-.LPG2(%r13) # load access regs needed by uaccess
+        l      %r14,.Lstart-.LPG2(%r13)
+        basr   %r14,%r14                # call start_kernel
+#
+# We returned from start_kernel ?!? PANIK
+#
+        basr  %r13,0
+	lpsw  .Ldw-.(%r13)           # load disabled wait psw
+#
+.Lstart:    .long  start_kernel
+            .align 8
+.Lprefix:   .long  init_S390_lowcore	
+.Linittu:   .long  init_task_union
+.Lbss_bgn:  .long  __bss_start
+.Lbss_end:  .long  _end
+.Locbits:   .long  0x01020408,0x10204080
+            .align 4
+.Laregs:    .long  0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0
+	    .align 8
+.Ldw:	    .long  0x000a0000,0x00000000
+
+#
+#        tempory segment-table at 0x11000
+#
+        .org   0x11000
+.Lpgd:  .long  .Lpt0+0x1f               # 00000000-000fffff
+        .long  .Lpt1+0x1f               # 00100000-001fffff
+        .long  .Lpt2+0x1f               # 00200000-002fffff
+        .long  .Lpt3+0x1f               # 00300000-003fffff
+        .fill  2044,4,0x20              # 00400000-7fffffff
+
+#
+#        tempory page-tables at 0x12000-0x15fff
+#
+        .macro  mktable from,to
+        .long   \from*0x10000
+        .long   \from*0x10000+0x1000
+        .long   \from*0x10000+0x2000
+        .long   \from*0x10000+0x3000
+        .long   \from*0x10000+0x4000
+        .long   \from*0x10000+0x5000
+        .long   \from*0x10000+0x6000
+        .long   \from*0x10000+0x7000
+        .long   \from*0x10000+0x8000
+        .long   \from*0x10000+0x9000
+        .long   \from*0x10000+0xa000
+        .long   \from*0x10000+0xb000
+        .long   \from*0x10000+0xc000
+        .long   \from*0x10000+0xd000
+        .long   \from*0x10000+0xe000
+        .long   \from*0x10000+0xf000
+        .if     \to-\from
+        mktable "(\from+1)",\to
+        .endif
+        .endm
+
+.Lpt0:  mktable 0,15
+.Lpt1:  mktable 16,31
+.Lpt2:  mktable 32,47
+.Lpt3:  mktable 48,63
+

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)