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authorMartin Schwidefsky <schwidefsky@de.ibm.com>2012-08-23 16:18:09 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2012-10-09 14:16:58 +0200
commit51eee033dca3d6dc81febc5a69f30b964f3bddf3 (patch)
tree5f5a7b981e2febf38671cb5808e4acddde0005d3 /arch
parentcc5b9a45184e90037e6d5353279ec358e57965fd (diff)
downloadlinux-51eee033dca3d6dc81febc5a69f30b964f3bddf3.tar.bz2
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>
Diffstat (limited to 'arch')
-rw-r--r--arch/s390/kernel/head.S101
1 files changed, 70 insertions, 31 deletions
diff --git a/arch/s390/kernel/head.S b/arch/s390/kernel/head.S
index 805b6686b641..984726cbce16 100644
--- a/arch/s390/kernel/head.S
+++ b/arch/s390/kernel/head.S
@@ -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