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+/* 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 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)
+ ahi %r15,-STACK_FRAME_OVERHEAD
+ brasl %r14,verify_facilities
+#ifdef CONFIG_KERNEL_UNCOMPRESSED
+ jg startup_continue
+#else
+ jg startup_decompressor
+#endif
+
+.Lstack:
+ .long 0x8000 + (1<<(PAGE_SHIFT+THREAD_SIZE_ORDER))
+ .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