From a438bdc1590195e7446427602bc7e4844969f773 Mon Sep 17 00:00:00 2001
From: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Date: Wed, 3 Aug 2011 16:44:22 +0200
Subject: [PATCH] --- yaml --- r: 262393 b: refs/heads/master c:
 9dc7356ee1266d6a69fc80f28d006f71c20bf172 h: refs/heads/master i:   262391:
 6d05d452221dde3d372667baf382bd3bfe1d554f v: v3

---
 [refs]                            |  2 +-
 trunk/arch/s390/include/asm/ipl.h |  1 +
 trunk/arch/s390/kernel/base.S     | 36 +++++++++++++++++++++++++++++++
 trunk/arch/s390/kernel/ipl.c      |  6 ++++++
 4 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 4ec364dbf6c4..613e0b0f130f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: ef1daec8da2c04b0c6e91a34b9cac1aad33c6692
+refs/heads/master: 9dc7356ee1266d6a69fc80f28d006f71c20bf172
diff --git a/trunk/arch/s390/include/asm/ipl.h b/trunk/arch/s390/include/asm/ipl.h
index 5e95d95450b3..97cc4403fabf 100644
--- a/trunk/arch/s390/include/asm/ipl.h
+++ b/trunk/arch/s390/include/asm/ipl.h
@@ -167,5 +167,6 @@ enum diag308_rc {
 };
 
 extern int diag308(unsigned long subcode, void *addr);
+extern void diag308_reset(void);
 
 #endif /* _ASM_S390_IPL_H */
diff --git a/trunk/arch/s390/kernel/base.S b/trunk/arch/s390/kernel/base.S
index 209938c1dfc8..255435663bf8 100644
--- a/trunk/arch/s390/kernel/base.S
+++ b/trunk/arch/s390/kernel/base.S
@@ -76,6 +76,42 @@ s390_base_pgm_handler_fn:
 	.quad	0
 	.previous
 
+#
+# Calls diag 308 subcode 1 and continues execution
+#
+# The following conditions must be ensured before calling this function:
+# * Prefix register = 0
+# * Lowcore protection is disabled
+#
+ENTRY(diag308_reset)
+	larl	%r4,.Lctlregs		# Save control registers
+	stctg	%c0,%c15,0(%r4)
+	larl	%r4,.Lrestart_psw	# Setup restart PSW at absolute 0
+	lghi	%r3,0
+	lg	%r4,0(%r4)		# Save PSW
+	sturg	%r4,%r3			# Use sturg, because of large pages
+	lghi	%r1,1
+	diag	%r1,%r1,0x308
+.Lrestart_part2:
+	lhi	%r0,0			# Load r0 with zero
+	lhi	%r1,2			# Use mode 2 = ESAME (dump)
+	sigp	%r1,%r0,0x12		# Switch to ESAME mode
+	sam64				# Switch to 64 bit addressing mode
+	larl	%r4,.Lctlregs		# Restore control registers
+	lctlg	%c0,%c15,0(%r4)
+	br	%r14
+.align 16
+.Lrestart_psw:
+	.long	0x00080000,0x80000000 + .Lrestart_part2
+
+	.section .bss
+.align 8
+.Lctlregs:
+	.rept	16
+	.quad	0
+	.endr
+	.previous
+
 #else /* CONFIG_64BIT */
 
 ENTRY(s390_base_mcck_handler)
diff --git a/trunk/arch/s390/kernel/ipl.c b/trunk/arch/s390/kernel/ipl.c
index 059c59027ac0..04361d5a4279 100644
--- a/trunk/arch/s390/kernel/ipl.c
+++ b/trunk/arch/s390/kernel/ipl.c
@@ -1996,6 +1996,12 @@ static void do_reset_calls(void)
 {
 	struct reset_call *reset;
 
+#ifdef CONFIG_64BIT
+	if (diag308_set_works) {
+		diag308_reset();
+		return;
+	}
+#endif
 	list_for_each_entry(reset, &rcall, list)
 		reset->fn();
 }