s390/entry: rely on long-displacement facility

Since commit 4efd417f29 ("s390: raise minimum supported machine
generation to z10"), the long-displacement facility is assumed and
required for the kernel. Clean up a couple of places in the entry code,
where long-displacement could be used directly instead of using a base
register.

However, there are still a few other places where a base register has
to be used to extend short-displacement for the second lowcore page
access. Notably, boot/head.S still has to be built for z900, and in
mcck_int_handler, spt and lbear, which don't have long-displacements,
but need to access save areas at the second lowcore page.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Vasily Gorbik 2023-03-28 11:09:09 +02:00
parent f62f8b716d
commit 385bf43c48

View File

@ -489,14 +489,13 @@ ENTRY(mcck_int_handler)
la %r1,4095 # validate r1
spt __LC_CPU_TIMER_SAVE_AREA-4095(%r1) # validate cpu timer
LBEAR __LC_LAST_BREAK_SAVE_AREA-4095(%r1) # validate bear
lmg %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# validate gprs
lmg %r0,%r15,__LC_GPREGS_SAVE_AREA # validate gprs
lmg %r8,%r9,__LC_MCK_OLD_PSW
TSTMSK __LC_MCCK_CODE,MCCK_CODE_SYSTEM_DAMAGE
jo .Lmcck_panic # yes -> rest of mcck code invalid
TSTMSK __LC_MCCK_CODE,MCCK_CODE_CR_VALID
jno .Lmcck_panic # control registers invalid -> panic
la %r14,4095
lctlg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r14) # validate ctl regs
lctlg %c0,%c15,__LC_CREGS_SAVE_AREA # validate ctl regs
ptlb
lghi %r14,__LC_CPU_TIMER_SAVE_AREA
mvc __LC_MCCK_ENTER_TIMER(8),0(%r14)
@ -594,8 +593,7 @@ ENTRY(restart_int_handler)
stg %r15,__LC_SAVE_AREA_RESTART
TSTMSK __LC_RESTART_FLAGS,RESTART_FLAG_CTLREGS,4
jz 0f
la %r15,4095
lctlg %c0,%c15,__LC_CREGS_SAVE_AREA-4095(%r15)
lctlg %c0,%c15,__LC_CREGS_SAVE_AREA
0: larl %r15,.Lstosm_tmp
stosm 0(%r15),0x04 # turn dat on, keep irqs off
lg %r15,__LC_RESTART_STACK