8 files changed, 115 insertions, 41 deletions

diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
index aa978978d3d1..a81881c9b297 100644
--- a/arch/s390/kernel/Makefile
+++ b/arch/s390/kernel/Makefile
@@ -4,7 +4,7 @@
 
 EXTRA_AFLAGS    := -traditional
 
-obj-y   :=  bitmap.o traps.o time.o process.o \
+obj-y   :=  bitmap.o traps.o time.o process.o reset.o \
             setup.o sys_s390.o ptrace.o signal.o cpcmd.o ebcdic.o \
             semaphore.o s390_ext.o debug.o profile.o irq.o ipl.o
 
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index ec127826f221..77f4aff630fe 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -19,6 +19,7 @@
 #include <asm/cpcmd.h>
 #include <asm/cio.h>
 #include <asm/ebcdic.h>
+#include <asm/reset.h>
 
 #define IPL_PARM_BLOCK_VERSION 0
 #define LOADPARM_LEN 8
@@ -1024,3 +1025,56 @@ static int __init s390_ipl_init(void)
 }
 
 __initcall(s390_ipl_init);
+
+static LIST_HEAD(rcall);
+static DEFINE_MUTEX(rcall_mutex);
+
+void register_reset_call(struct reset_call *reset)
+{
+        mutex_lock(&rcall_mutex);
+        list_add(&reset->list, &rcall);
+        mutex_unlock(&rcall_mutex);
+}
+EXPORT_SYMBOL_GPL(register_reset_call);
+
+void unregister_reset_call(struct reset_call *reset)
+{
+        mutex_lock(&rcall_mutex);
+        list_del(&reset->list);
+        mutex_unlock(&rcall_mutex);
+}
+EXPORT_SYMBOL_GPL(unregister_reset_call);
+
+static void do_reset_calls(void)
+{
+        struct reset_call *reset;
+
+        list_for_each_entry(reset, &rcall, list)
+                reset->fn();
+}
+
+extern void reset_mcck_handler(void);
+
+void s390_reset_system(void)
+{
+        struct _lowcore *lc;
+
+        /* Disable all interrupts/machine checks */
+        __load_psw_mask(PSW_KERNEL_BITS & ~PSW_MASK_MCHECK);
+
+        /* Stack for interrupt/machine check handler */
+        lc = (struct _lowcore *)(unsigned long) store_prefix();
+        lc->panic_stack = S390_lowcore.panic_stack;
+
+        /* Disable prefixing */
+        set_prefix(0);
+
+        /* Disable lowcore protection */
+        __ctl_clear_bit(0,28);
+
+        /* Set new machine check handler */
+        S390_lowcore.mcck_new_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_MCHECK;
+        S390_lowcore.mcck_new_psw.addr =
+                PSW_ADDR_AMODE | (unsigned long) &reset_mcck_handler;
+        do_reset_calls();
+}
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c
index 60b1ea9f946b..202bf1fdfe39 100644
--- a/arch/s390/kernel/machine_kexec.c
+++ b/arch/s390/kernel/machine_kexec.c
@@ -22,6 +22,7 @@
 #include <asm/pgalloc.h>
 #include <asm/system.h>
 #include <asm/smp.h>
+#include <asm/reset.h>
 
 static void kexec_halt_all_cpus(void *);
 
@@ -62,12 +63,6 @@ machine_shutdown(void)
 NORET_TYPE void
 machine_kexec(struct kimage *image)
 {
-        clear_all_subchannels();
-        cio_reset_channel_paths();
-
-        /* Disable lowcore protection */
-        ctl_clear_bit(0,28);
-
         on_each_cpu(kexec_halt_all_cpus, image, 0, 0);
         for (;;);
 }
@@ -98,6 +93,8 @@ kexec_halt_all_cpus(void *kernel_image)
                         cpu_relax();
         }
 
+        s390_reset_system();
+
         image = (struct kimage *) kernel_image;
         data_mover = (relocate_kernel_t)
                 (page_to_pfn(image->control_code_page) << PAGE_SHIFT);
diff --git a/arch/s390/kernel/reipl.S b/arch/s390/kernel/reipl.S
index 0340477f3b08..f9434d42ce9f 100644
--- a/arch/s390/kernel/reipl.S
+++ b/arch/s390/kernel/reipl.S
@@ -11,19 +11,10 @@
                 .globl  do_reipl_asm
 do_reipl_asm:   basr    %r13,0
 .Lpg0:          lpsw    .Lnewpsw-.Lpg0(%r13)
-
-                # switch off lowcore protection
-
-.Lpg1:          stctl   %c0,%c0,.Lctlsave1-.Lpg0(%r13)
-                stctl   %c0,%c0,.Lctlsave2-.Lpg0(%r13)
-                ni      .Lctlsave1-.Lpg0(%r13),0xef
-                lctl    %c0,%c0,.Lctlsave1-.Lpg0(%r13)
-
-                # do store status of all registers
+.Lpg1:          # do store status of all registers
 
                 stm     %r0,%r15,__LC_GPREGS_SAVE_AREA
                 stctl   %c0,%c15,__LC_CREGS_SAVE_AREA
-                mvc     __LC_CREGS_SAVE_AREA(4),.Lctlsave2-.Lpg0(%r13)
                 stam    %a0,%a15,__LC_AREGS_SAVE_AREA
                 stpx    __LC_PREFIX_SAVE_AREA
                 stckc   .Lclkcmp-.Lpg0(%r13)
@@ -56,8 +47,7 @@ do_reipl_asm:	basr	%r13,0
 .L002:          tm      .Liplirb+8-.Lpg0(%r13),0xf3
                 jz      .L003
                 bas     %r14,.Ldisab-.Lpg0(%r13)
-.L003:          spx     .Lnull-.Lpg0(%r13)
-                st      %r1,__LC_SUBCHANNEL_ID
+.L003:          st      %r1,__LC_SUBCHANNEL_ID
                 lpsw    0
                 sigp    0,0,0(6)
 .Ldisab:        st      %r14,.Ldispsw+4-.Lpg0(%r13)
@@ -65,9 +55,6 @@ do_reipl_asm:	basr	%r13,0
                 .align  8
 .Lclkcmp:       .quad   0x0000000000000000
 .Lall:          .long   0xff000000
-.Lnull:         .long   0x00000000
-.Lctlsave1:     .long   0x00000000
-.Lctlsave2:     .long   0x00000000
                 .align  8
 .Lnewpsw:       .long   0x00080000,0x80000000+.Lpg1
 .Lpcnew:        .long   0x00080000,0x80000000+.Lecs
diff --git a/arch/s390/kernel/reipl64.S b/arch/s390/kernel/reipl64.S
index de7435054f7c..f18ef260ca23 100644
--- a/arch/s390/kernel/reipl64.S
+++ b/arch/s390/kernel/reipl64.S
@@ -10,10 +10,10 @@
 #include <asm/lowcore.h>
                 .globl  do_reipl_asm
 do_reipl_asm:   basr    %r13,0
+.Lpg0:          lpswe   .Lnewpsw-.Lpg0(%r13)
+.Lpg1:          # do store status of all registers
 
-                # do store status of all registers
-
-.Lpg0:          stg     %r1,.Lregsave-.Lpg0(%r13)
+                stg     %r1,.Lregsave-.Lpg0(%r13)
                 lghi    %r1,0x1000
                 stmg    %r0,%r15,__LC_GPREGS_SAVE_AREA-0x1000(%r1)
                 lg      %r0,.Lregsave-.Lpg0(%r13)
@@ -27,11 +27,7 @@ do_reipl_asm:	basr	%r13,0
                 stpt    __LC_CPU_TIMER_SAVE_AREA-0x1000(%r1)
                 stg     %r13, __LC_PSW_SAVE_AREA-0x1000+8(%r1)
 
-                lpswe   .Lnewpsw-.Lpg0(%r13)
-.Lpg1:          lctlg   %c6,%c6,.Lall-.Lpg0(%r13)
-                stctg   %c0,%c0,.Lregsave-.Lpg0(%r13)
-                ni      .Lregsave+4-.Lpg0(%r13),0xef
-                lctlg   %c0,%c0,.Lregsave-.Lpg0(%r13)
+                lctlg   %c6,%c6,.Lall-.Lpg0(%r13)
                 lgr     %r1,%r2
                 mvc     __LC_PGM_NEW_PSW(16),.Lpcnew-.Lpg0(%r13)
                 stsch   .Lschib-.Lpg0(%r13)
@@ -56,8 +52,7 @@ do_reipl_asm:	basr	%r13,0
 .L002:          tm      .Liplirb+8-.Lpg0(%r13),0xf3
                 jz      .L003
                 bas     %r14,.Ldisab-.Lpg0(%r13)
-.L003:          spx     .Lnull-.Lpg0(%r13)
-                st      %r1,__LC_SUBCHANNEL_ID
+.L003:          st      %r1,__LC_SUBCHANNEL_ID
                 lhi     %r1,0            # mode 0 = esa
                 slr     %r0,%r0          # set cpuid to zero
                 sigp    %r1,%r0,0x12     # switch to esa mode
@@ -70,7 +65,6 @@ do_reipl_asm:	basr	%r13,0
 .Lclkcmp:       .quad   0x0000000000000000
 .Lall:          .quad   0x00000000ff000000
 .Lregsave:      .quad   0x0000000000000000
-.Lnull:         .long   0x0000000000000000
                 .align  16
 /*
  * These addresses have to be 31 bit otherwise
diff --git a/arch/s390/kernel/relocate_kernel.S b/arch/s390/kernel/relocate_kernel.S
index f9899ff2e5b0..3b456b80bcee 100644
--- a/arch/s390/kernel/relocate_kernel.S
+++ b/arch/s390/kernel/relocate_kernel.S
@@ -26,8 +26,7 @@
         relocate_kernel:
                 basr    %r13,0          # base address
         .base:
-                stnsm   sys_msk-.base(%r13),0xf8        # disable DAT and IRQ (external)
-                spx     zero64-.base(%r13)      # absolute addressing mode
+                stnsm   sys_msk-.base(%r13),0xfb        # disable DAT
                 stctl   %c0,%c15,ctlregs-.base(%r13)
                 stm     %r0,%r15,gprregs-.base(%r13)
                 la      %r1,load_psw-.base(%r13)
@@ -97,8 +96,6 @@
                 lpsw    0               # hopefully start new kernel...
 
                 .align  8
-        zero64:
-                .quad   0
         load_psw:
                 .long   0x00080000,0x80000000
         sys_msk:
diff --git a/arch/s390/kernel/relocate_kernel64.S b/arch/s390/kernel/relocate_kernel64.S
index 4fb443042d9c..1f9ea2067b59 100644
--- a/arch/s390/kernel/relocate_kernel64.S
+++ b/arch/s390/kernel/relocate_kernel64.S
@@ -27,8 +27,7 @@
         relocate_kernel:
                 basr    %r13,0          # base address
         .base:
-                stnsm   sys_msk-.base(%r13),0xf8        # disable DAT and IRQs
-                spx     zero64-.base(%r13)      # absolute addressing mode
+                stnsm   sys_msk-.base(%r13),0xfb        # disable DAT
                 stctg   %c0,%c15,ctlregs-.base(%r13)
                 stmg    %r0,%r15,gprregs-.base(%r13)
                 lghi    %r0,3
@@ -100,8 +99,6 @@
                 lpsw    0               # hopefully start new kernel...
 
                 .align  8
-        zero64:
-                .quad   0
         load_psw:
                 .long   0x00080000,0x80000000
         sys_msk:
diff --git a/arch/s390/kernel/reset.S b/arch/s390/kernel/reset.S
new file mode 100644
index 000000000000..be8688c0665c
--- /dev/null
+++ b/arch/s390/kernel/reset.S
@@ -0,0 +1,48 @@
+/*
+ *  arch/s390/kernel/reset.S
+ *
+ *    Copyright (C) IBM Corp. 2006
+ *    Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
+ */
+
+#include <asm/ptrace.h>
+#include <asm/lowcore.h>
+
+#ifdef CONFIG_64BIT
+
+        .globl  reset_mcck_handler
+reset_mcck_handler:
+        basr    %r13,0
+0:      lg      %r15,__LC_PANIC_STACK   # load panic stack
+        aghi    %r15,-STACK_FRAME_OVERHEAD
+        lg      %r1,s390_reset_mcck_handler-0b(%r13)
+        ltgr    %r1,%r1
+        jz      1f
+        basr    %r14,%r1
+1:      la      %r1,4095
+        lmg     %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)
+        lpswe   __LC_MCK_OLD_PSW
+
+        .globl  s390_reset_mcck_handler
+s390_reset_mcck_handler:
+        .quad   0
+
+#else /* CONFIG_64BIT */
+
+        .globl  reset_mcck_handler
+reset_mcck_handler:
+        basr    %r13,0
+0:      l       %r15,__LC_PANIC_STACK   # load panic stack
+        ahi     %r15,-STACK_FRAME_OVERHEAD
+        l       %r1,s390_reset_mcck_handler-0b(%r13)
+        ltr     %r1,%r1
+        jz      1f
+        basr    %r14,%r1
+1:      lm      %r0,%r15,__LC_GPREGS_SAVE_AREA
+        lpsw    __LC_MCK_OLD_PSW
+
+        .globl  s390_reset_mcck_handler
+s390_reset_mcck_handler:
+        .long   0
+
+#endif /* CONFIG_64BIT */