Message ID | 1479838000-380-1-git-send-email-ego@linux.vnet.ibm.com (mailing list archive) |
---|---|
State | Accepted |
Headers | show |
"Gautham R. Shenoy" <ego@linux.vnet.ibm.com> writes: > From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> > > Ensure that PSSCR is set to a safe value corresponding to no > state-loss each time a POWER9 CPU comes online. Is this a bug fix? I can't tell from the change log. cheers
On Wed, 2016-11-23 at 10:30 +1100, Michael Ellerman wrote: > "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> writes: > > > From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> > > > > Ensure that PSSCR is set to a safe value corresponding to no > > state-loss each time a POWER9 CPU comes online. > > Is this a bug fix? I can't tell from the change log. There are no known bugs it's fixing. It's just safer to run with a known default value, rather than what we randomly inherit from previous firmware. Mikey
On Tue, 2016-11-22 at 23:36 +0530, Gautham R. Shenoy wrote: > From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> > > Ensure that PSSCR is set to a safe value corresponding to no > state-loss each time a POWER9 CPU comes online. > > Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Tested here on my configuration... FWIW Acked-By: Michael Neuling <mikey@neuling.org> > --- > arch/powerpc/kernel/cpu_setup_power.S | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/arch/powerpc/kernel/cpu_setup_power.S > b/arch/powerpc/kernel/cpu_setup_power.S > index 52ff3f0..37ad045 100644 > --- a/arch/powerpc/kernel/cpu_setup_power.S > +++ b/arch/powerpc/kernel/cpu_setup_power.S > @@ -96,6 +96,7 @@ _GLOBAL(__setup_cpu_power9) > mtlr r11 > beqlr > li r0,0 > + mtspr SPRN_PSSCR,r0 > mtspr SPRN_LPID,r0 > mfspr r3,SPRN_LPCR > ori r3, r3, LPCR_PECEDH > @@ -116,6 +117,7 @@ _GLOBAL(__restore_cpu_power9) > mtlr r11 > beqlr > li r0,0 > + mtspr SPRN_PSSCR,r0 > mtspr SPRN_LPID,r0 > mfspr r3,SPRN_LPCR > ori r3, r3, LPCR_PECEDH
On Tue, 2016-11-22 at 18:06:40 UTC, "Gautham R. Shenoy" wrote: > From: "Gautham R. Shenoy" <ego@linux.vnet.ibm.com> > > Ensure that PSSCR is set to a safe value corresponding to no > state-loss each time a POWER9 CPU comes online. > > Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> > Acked-By: Michael Neuling <mikey@neuling.org> Applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/378f96d3cd442d5cb8e2692d8767a4 cheers
diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S index 52ff3f0..37ad045 100644 --- a/arch/powerpc/kernel/cpu_setup_power.S +++ b/arch/powerpc/kernel/cpu_setup_power.S @@ -96,6 +96,7 @@ _GLOBAL(__setup_cpu_power9) mtlr r11 beqlr li r0,0 + mtspr SPRN_PSSCR,r0 mtspr SPRN_LPID,r0 mfspr r3,SPRN_LPCR ori r3, r3, LPCR_PECEDH @@ -116,6 +117,7 @@ _GLOBAL(__restore_cpu_power9) mtlr r11 beqlr li r0,0 + mtspr SPRN_PSSCR,r0 mtspr SPRN_LPID,r0 mfspr r3,SPRN_LPCR ori r3, r3, LPCR_PECEDH