powerpc: Add NAP mode support on Power7 in HV mode

[pandora-kernel.git] / arch / powerpc / kernel / exceptions-64s.S

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index e513c1d..ad06333 100644 (file)
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -37,7 +37,35 @@
        .globl __start_interrupts
 __start_interrupts:
 
-       STD_EXCEPTION_PSERIES(0x100, 0x100, system_reset)
+       .globl system_reset_pSeries;
+system_reset_pSeries:
+       HMT_MEDIUM;
+       DO_KVM  0x100;
+       SET_SCRATCH0(r13)
+#ifdef CONFIG_PPC_P7_NAP
+BEGIN_FTR_SECTION
+       /* Running native on arch 2.06 or later, check if we are
+        * waking up from nap. We only handle no state loss and
+        * supervisor state loss. We do -not- handle hypervisor
+        * state loss at this time.
+        */
+       mfspr   r13,SPRN_SRR1
+       rlwinm  r13,r13,47-31,30,31
+       cmpwi   cr0,r13,1
+       bne     1f
+       b       .power7_wakeup_noloss
+1:     cmpwi   cr0,r13,2
+       bne     1f
+       b       .power7_wakeup_loss
+       /* Total loss of HV state is fatal, we could try to use the
+        * PIR to locate a PACA, then use an emergency stack etc...
+        * but for now, let's just stay stuck here
+        */
+1:     cmpwi   cr0,r13,3
+       beq     .
+END_FTR_SECTION_IFSET(CPU_FTR_HVMODE_206)
+#endif /* CONFIG_PPC_P7_NAP */
+       EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, system_reset_common, EXC_STD)
 
        . = 0x200
 _machine_check_pSeries: