s390: add support to start the kernel in 64 bit mode.

Do the switch to z/Architecture (alias 64 bit) mode early in head.S.
If the machine is already running in 64 bit mode the sigp turns into
a nop. With this change it doesn't matter in which mode the kernel
is started.

Reviewd-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2012-08-23 16:18:09 +02:00
parent cc5b9a4518
commit 51eee033dc

View File

@ -52,7 +52,7 @@ __HEAD
.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 0x02000460,0x60000050 # at 0x200 = iplstart.
.long 0x020004b0,0x60000050
.long 0x02000500,0x60000050
.long 0x02000550,0x60000050
@ -62,11 +62,54 @@ __HEAD
.long 0x02000690,0x60000050
.long 0x020006e0,0x20000050
.org 0xf0
.org 0x200
#
# subroutine to set architecture mode
#
.Lsetmode:
#ifdef CONFIG_64BIT
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
#else
mvi __LC_AR_MODE_ID,0 # set ESA flag (mode 0)
#endif
br %r14
#
# subroutine to wait for end I/O
#
.Lirqwait:
#ifdef CONFIG_64BIT
mvc 0x1f0(16),.Lnewpsw # set up IO interrupt psw
lpsw .Lwaitpsw
.Lioint:
br %r14
.align 8
.Lnewpsw:
.quad 0x0000000080000000,.Lioint
#else
mvc 0x78(8),.Lnewpsw # set up IO interrupt psw
lpsw .Lwaitpsw
.Lioint:
br %r14
.align 8
.Lnewpsw:
.long 0x00080000,0x80000000+.Lioint
#endif
.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
@ -83,9 +126,7 @@ __HEAD
ssch 0(%r3) # load chunk of 1600 bytes
bnz .Llderr
.Lwait4irq:
mvc 0x78(8),.Lnewpsw # set up IO interrupt psw
lpsw .Lwaitpsw
.Lioint:
bas %r14,.Lirqwait
c %r1,0xb8 # compare subchannel number
bne .Lwait4irq
tsch 0(%r5)
@ -104,7 +145,7 @@ __HEAD
sr %r0,%r3 # #ccws*80-residual=#bytes read
ar %r2,%r0
br %r14 # r2 contains the total size
br %r4 # r2 contains the total size
.Lcont:
ahi %r2,0x640 # add 0x640 to total size
@ -128,10 +169,6 @@ __HEAD
.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
@ -140,6 +177,7 @@ __HEAD
.long 0x02200050,0x00000000
iplstart:
bas %r14,.Lsetmode # Immediately switch to 64 bit mode
lh %r1,0xb8 # test if subchannel number
bct %r1,.Lnoload # is valid
l %r1,0xb8 # load ipl subchannel number
@ -209,8 +247,8 @@ iplstart:
#
# reset files in VM reader
#
stidp __LC_SAVE_AREA_SYNC # store cpuid
tm __LC_SAVE_AREA_SYNC,0xff# running VM ?
stidp .Lcpuid # store cpuid
tm .Lcpuid,0xff # running VM ?
bno .Lnoreset
la %r2,.Lreset
lhi %r3,26
@ -222,23 +260,14 @@ iplstart:
tm 31(%r5),0xff # bits is set in the schib
bz .Lnoreset
.Lwaitforirq:
mvc 0x78(8),.Lrdrnewpsw # set up IO interrupt psw
.Lwaitrdrirq:
lpsw .Lrdrwaitpsw
.Lrdrint:
bas %r14,.Lirqwait # wait for IO interrupt
c %r1,0xb8 # compare subchannel number
bne .Lwaitrdrirq
bne .Lwaitforirq
la %r5,.Lirb
tsch 0(%r5)
.Lnoreset:
b .Lnoload
.align 8
.Lrdrnewpsw:
.long 0x00080000,0x80000000+.Lrdrint
.Lrdrwaitpsw:
.long 0x020a0000,0x80000000+.Lrdrint
#
# everything loaded, go for it
#
@ -254,6 +283,8 @@ iplstart:
.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
#
# SALIPL loader support. Based on a patch by Rob van der Heij.
@ -263,6 +294,7 @@ iplstart:
.org 0x800
ENTRY(start)
stm %r0,%r15,0x07b0 # store registers
bas %r14,.Lsetmode # Immediately switch to 64 bit mode
basr %r12,%r0
.base:
l %r11,.parm
@ -343,6 +375,18 @@ ENTRY(startup)
ENTRY(startup_kdump)
j .Lep_startup_kdump
.Lep_startup_normal:
#ifdef CONFIG_64BIT
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
#else
mvi __LC_AR_MODE_ID,0 # set ESA flag (mode 0)
#endif
basr %r13,0 # get base
.LPG0:
xc 0x200(256),0x200 # partially clear lowcore
@ -410,22 +454,17 @@ ENTRY(startup_kdump)
#endif
#ifdef CONFIG_64BIT
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
/* Continue with 64bit startup code in head64.S */
sam64 # switch to 64 bit mode
larl %r13,4f
lmh %r0,%r15,0(%r13) # clear high-order half
jg startup_continue
4: .fill 16,4,0x0
#else
mvi __LC_AR_MODE_ID,0 # set ESA flag (mode 0)
/* Continue with 31bit startup code in head31.S */
l %r13,4f-.LPG0(%r13)
b 0(%r13)
.align 8
4: .long startup_continue
#endif
.align 8
5: .long 0x7fffffff,0xffffffff