[RFC,v4,05/12] powerpc/book3s: Introduce a early machine check hook in cpu_spec.

Submitted by Mahesh Salgaonkar on Sept. 16, 2013, 12:41 p.m.

Details

Message ID 20130916124132.16111.8861.stgit@mars.in.ibm.com
State Superseded
Headers show

Commit Message

Mahesh Salgaonkar Sept. 16, 2013, 12:41 p.m.
From: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>

This patch adds the early machine check function pointer in cputable for
CPU specific early machine check handling. The early machine handle routine
will be called in real mode to handle SLB and TLB errors. We can not reuse
the existing machine_check hook because it is always invoked in kernel
virtual mode and we would already be in trouble if we get SLB or TLB errors.
This patch just sets up a mechanism to invoke CPU specific handler. The
subsequent patches will populate the function pointer.

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
---
 arch/powerpc/include/asm/cputable.h |    7 +++++++
 arch/powerpc/kernel/traps.c         |    7 +++++--
 2 files changed, 12 insertions(+), 2 deletions(-)

Patch hide | download patch | download mbox

diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h
index 6f3887d..d8c098e 100644
--- a/arch/powerpc/include/asm/cputable.h
+++ b/arch/powerpc/include/asm/cputable.h
@@ -90,6 +90,13 @@  struct cpu_spec {
 	 * if the error is fatal, 1 if it was fully recovered and 0 to
 	 * pass up (not CPU originated) */
 	int		(*machine_check)(struct pt_regs *regs);
+
+	/*
+	 * Processor specific early machine check handler which is
+	 * called in real mode to handle SLB and TLB errors.
+	 */
+	long		(*machine_check_early)(struct pt_regs *regs);
+
 };
 
 extern struct cpu_spec		*cur_cpu_spec;
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index e8d6bf1..8b0a946 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -292,8 +292,11 @@  void system_reset_exception(struct pt_regs *regs)
  */
 long machine_check_early(struct pt_regs *regs)
 {
-	/* TODO: handle/decode machine check reason */
-	return 0;
+	long handled = 0;
+
+	if (cur_cpu_spec && cur_cpu_spec->machine_check_early)
+		handled = cur_cpu_spec->machine_check_early(regs);
+	return handled;
 }
 
 #endif