On Tue, Nov 22, 2016 at 11:06:32PM +0530, Gautham R. Shenoy wrote: > From: "Gautham R. Shenoy" <e...@linux.vnet.ibm.com> > > The existing code doesn't handle the case when CPU which was in a > hardware-idle state (nap,sleep,winkle on POWER8 and various stop > states on POWER9) gets woken up due to a System Reset interrupt. > > This patch checks if the CPU was woken up due to System Reset, in > which case, after restoring the required hardware state, it jumps to > the system reset handler. > > Signed-off-by: Gautham R. Shenoy <e...@linux.vnet.ibm.com> > --- > v1 -> v2: Set r9,r11,r12 to CR,SRR0,SRR1 values > before jumping to system_reset_common as expected by > EXCEPTION_PROLOG_COMMON > > arch/powerpc/kernel/idle_book3s.S | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/arch/powerpc/kernel/idle_book3s.S > b/arch/powerpc/kernel/idle_book3s.S > index 72dac0b..06afe0e 100644 > --- a/arch/powerpc/kernel/idle_book3s.S > +++ b/arch/powerpc/kernel/idle_book3s.S > @@ -353,6 +353,22 @@ ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_ARCH_207S, 66); > \ > ld r3,ORIG_GPR3(r1); /* Restore original r3 */ \ > 20: nop; > > +#define CHECK_SRESET_INTERRUPT \ > +BEGIN_FTR_SECTION_NESTED(67); > \ > + mfspr r0,SPRN_SRR1; \ > + rlwinm r0,r0,45-31,0xf; /* Extract wake reason field (P8,9) */ \ > + cmpwi r0,0x4; /* System Reset ? */ \ > + bne 21f; \ > + ld r1,PACAR1(r13); \ > + ld r9,_CCR(r1); \ > + ld r11,_NIP(r1); \ > + mfspr r12, SPRN_SRR1; \ > + b system_reset_common ; \ > + b .; /* We shouldn't return here */ \ > +FTR_SECTION_ELSE_NESTED(67); \ > + nop ; \ > +ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_ARCH_207S, 67); \
What's the point of the else section? Paul.
