* [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry @ 2014-06-02 6:57 Michael Neuling 2014-06-02 6:57 ` [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs Michael Neuling 2014-06-05 3:05 ` [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry Preeti U Murthy 0 siblings, 2 replies; 7+ messages in thread From: Michael Neuling @ 2014-06-02 6:57 UTC (permalink / raw) To: Benjamin Herrenschmidt Cc: Preeti U Murthy, linuxppc-dev, Paul Mackerras, Anton Blanchard Currently when entering fastsleep we clear all LPCR PECE bits. This patch changes it to only clear the decrementer bit (ie. PECE1), which is the only bit we really need to clear here. This is needed if we want to set other wakeup causes like the PECEDH bit so we can use hypervisor doorbells on powernv. Signed-off-by: Michael Neuling <mikey@neuling.org> --- drivers/cpuidle/cpuidle-powernv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 719f6fb..7f7798e 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -73,7 +73,7 @@ static int fastsleep_loop(struct cpuidle_device *dev, return index; new_lpcr = old_lpcr; - new_lpcr &= ~(LPCR_MER | LPCR_PECE); /* lpcr[mer] must be 0 */ + new_lpcr &= ~(LPCR_MER | LPCR_PECE1); /* lpcr[mer] must be 0 */ /* exit powersave upon external interrupt, but not decrementer * interrupt. -- 1.9.1 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs 2014-06-02 6:57 [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry Michael Neuling @ 2014-06-02 6:57 ` Michael Neuling 2014-06-02 22:06 ` Anton Blanchard 2014-06-04 8:03 ` Michael Ellerman 2014-06-05 3:05 ` [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry Preeti U Murthy 1 sibling, 2 replies; 7+ messages in thread From: Michael Neuling @ 2014-06-02 6:57 UTC (permalink / raw) To: Benjamin Herrenschmidt Cc: Preeti U Murthy, linuxppc-dev, Paul Mackerras, Anton Blanchard This patch enables POWER8 doorbell IPIs on powernv. Since doorbells can only IPI within a core, we test to see when we can use doorbells and if not we fall back to XICS. This also enables hypervisor doorbells to wakeup us up from nap/sleep via the LPCR PECEDH bit. Based on tests by Anton, the best case IPI latency between two threads dropped from 894ns to 512ns. Signed-off-by: Michael Neuling <mikey@neuling.org> --- arch/powerpc/kernel/cpu_setup_power.S | 2 ++ arch/powerpc/platforms/powernv/smp.c | 6 ++++++ arch/powerpc/sysdev/xics/icp-native.c | 9 ++++++++- 3 files changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S index 1557e7c..4673353 100644 --- a/arch/powerpc/kernel/cpu_setup_power.S +++ b/arch/powerpc/kernel/cpu_setup_power.S @@ -56,6 +56,7 @@ _GLOBAL(__setup_cpu_power8) li r0,0 mtspr SPRN_LPID,r0 mfspr r3,SPRN_LPCR + ori r3, r3, LPCR_PECEDH bl __init_LPCR bl __init_HFSCR bl __init_tlb_power8 @@ -74,6 +75,7 @@ _GLOBAL(__restore_cpu_power8) li r0,0 mtspr SPRN_LPID,r0 mfspr r3,SPRN_LPCR + ori r3, r3, LPCR_PECEDH bl __init_LPCR bl __init_HFSCR bl __init_tlb_power8 diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c index 0062a43..5fcfcf4 100644 --- a/arch/powerpc/platforms/powernv/smp.c +++ b/arch/powerpc/platforms/powernv/smp.c @@ -32,6 +32,7 @@ #include <asm/opal.h> #include <asm/runlatch.h> #include <asm/code-patching.h> +#include <asm/dbell.h> #include "powernv.h" @@ -46,6 +47,11 @@ static void pnv_smp_setup_cpu(int cpu) { if (cpu != boot_cpuid) xics_setup_cpu(); + +#ifdef CONFIG_PPC_DOORBELL + if (cpu_has_feature(CPU_FTR_DBELL)) + doorbell_setup_this_cpu(); +#endif } int pnv_smp_kick_cpu(int nr) diff --git a/arch/powerpc/sysdev/xics/icp-native.c b/arch/powerpc/sysdev/xics/icp-native.c index 9dee470..de8d948 100644 --- a/arch/powerpc/sysdev/xics/icp-native.c +++ b/arch/powerpc/sysdev/xics/icp-native.c @@ -26,6 +26,7 @@ #include <asm/errno.h> #include <asm/xics.h> #include <asm/kvm_ppc.h> +#include <asm/dbell.h> struct icp_ipl { union { @@ -145,7 +146,13 @@ static unsigned int icp_native_get_irq(void) static void icp_native_cause_ipi(int cpu, unsigned long data) { kvmppc_set_host_ipi(cpu, 1); - icp_native_set_qirr(cpu, IPI_PRIORITY); +#ifdef CONFIG_PPC_DOORBELL + if (cpu_has_feature(CPU_FTR_DBELL) && + (cpumask_test_cpu(cpu, cpu_sibling_mask(smp_processor_id())))) + doorbell_cause_ipi(cpu, data); + else +#endif + icp_native_set_qirr(cpu, IPI_PRIORITY); } void xics_wake_cpu(int cpu) -- 1.9.1 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs 2014-06-02 6:57 ` [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs Michael Neuling @ 2014-06-02 22:06 ` Anton Blanchard 2014-06-04 8:03 ` Michael Ellerman 1 sibling, 0 replies; 7+ messages in thread From: Anton Blanchard @ 2014-06-02 22:06 UTC (permalink / raw) To: Michael Neuling; +Cc: Preeti U Murthy, Paul Mackerras, linuxppc-dev Hi, > This patch enables POWER8 doorbell IPIs on powernv. > > Since doorbells can only IPI within a core, we test to see when we > can use doorbells and if not we fall back to XICS. This also enables > hypervisor doorbells to wakeup us up from nap/sleep via the LPCR > PECEDH bit. > > Based on tests by Anton, the best case IPI latency between two > threads dropped from 894ns to 512ns. > > Signed-off-by: Michael Neuling <mikey@neuling.org> Thanks Mikey! Tested-by: Anton Blanchard <anton@samba.org> Anton ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs 2014-06-02 6:57 ` [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs Michael Neuling 2014-06-02 22:06 ` Anton Blanchard @ 2014-06-04 8:03 ` Michael Ellerman 2014-06-04 9:38 ` Michael Neuling 2014-06-04 11:05 ` [PATCH v2 " Michael Neuling 1 sibling, 2 replies; 7+ messages in thread From: Michael Ellerman @ 2014-06-04 8:03 UTC (permalink / raw) To: Michael Neuling Cc: Preeti U Murthy, linuxppc-dev, Anton Blanchard, Paul Mackerras On Mon, 2014-06-02 at 16:57 +1000, Michael Neuling wrote: > This patch enables POWER8 doorbell IPIs on powernv. > > Since doorbells can only IPI within a core, we test to see when we can use > doorbells and if not we fall back to XICS. This also enables hypervisor > doorbells to wakeup us up from nap/sleep via the LPCR PECEDH bit. > > Based on tests by Anton, the best case IPI latency between two threads dropped > from 894ns to 512ns. > > Signed-off-by: Michael Neuling <mikey@neuling.org> > --- > arch/powerpc/kernel/cpu_setup_power.S | 2 ++ > arch/powerpc/platforms/powernv/smp.c | 6 ++++++ > arch/powerpc/sysdev/xics/icp-native.c | 9 ++++++++- > 3 files changed, 16 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cpu_setup_power.S > index 1557e7c..4673353 100644 > --- a/arch/powerpc/kernel/cpu_setup_power.S > +++ b/arch/powerpc/kernel/cpu_setup_power.S > @@ -56,6 +56,7 @@ _GLOBAL(__setup_cpu_power8) > li r0,0 > mtspr SPRN_LPID,r0 > mfspr r3,SPRN_LPCR > + ori r3, r3, LPCR_PECEDH > bl __init_LPCR > bl __init_HFSCR > bl __init_tlb_power8 > @@ -74,6 +75,7 @@ _GLOBAL(__restore_cpu_power8) > li r0,0 > mtspr SPRN_LPID,r0 > mfspr r3,SPRN_LPCR > + ori r3, r3, LPCR_PECEDH > bl __init_LPCR > bl __init_HFSCR > bl __init_tlb_power8 > diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c > index 0062a43..5fcfcf4 100644 > --- a/arch/powerpc/platforms/powernv/smp.c > +++ b/arch/powerpc/platforms/powernv/smp.c > @@ -32,6 +32,7 @@ > #include <asm/opal.h> > #include <asm/runlatch.h> > #include <asm/code-patching.h> > +#include <asm/dbell.h> > > #include "powernv.h" > > @@ -46,6 +47,11 @@ static void pnv_smp_setup_cpu(int cpu) > { > if (cpu != boot_cpuid) > xics_setup_cpu(); > + > +#ifdef CONFIG_PPC_DOORBELL > + if (cpu_has_feature(CPU_FTR_DBELL)) > + doorbell_setup_this_cpu(); > +#endif > } Where does CONFIG_PPC_DOORBELL get set? It looks like the only place you can be getting it is from CONFIG_PPC_PSERIES. If you build a POWERNV only kernel it will get disabled, which I don't think is what we want. I think we should select it for POWERNV as well as PSERIES. That would mean it's always enabled for any build of the files you touch, so you shouldn't need the #ifdefs. cheers ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs 2014-06-04 8:03 ` Michael Ellerman @ 2014-06-04 9:38 ` Michael Neuling 2014-06-04 11:05 ` [PATCH v2 " Michael Neuling 1 sibling, 0 replies; 7+ messages in thread From: Michael Neuling @ 2014-06-04 9:38 UTC (permalink / raw) To: Michael Ellerman Cc: Preeti U Murthy, linuxppc-dev, Anton Blanchard, Paul Mackerras On Wed, 2014-06-04 at 18:03 +1000, Michael Ellerman wrote: > On Mon, 2014-06-02 at 16:57 +1000, Michael Neuling wrote: > > This patch enables POWER8 doorbell IPIs on powernv. > >=20 > > Since doorbells can only IPI within a core, we test to see when we can = use > > doorbells and if not we fall back to XICS. This also enables hyperviso= r > > doorbells to wakeup us up from nap/sleep via the LPCR PECEDH bit. > >=20 > > Based on tests by Anton, the best case IPI latency between two threads = dropped > > from 894ns to 512ns. > >=20 > > Signed-off-by: Michael Neuling <mikey@neuling.org> > > --- > > arch/powerpc/kernel/cpu_setup_power.S | 2 ++ > > arch/powerpc/platforms/powernv/smp.c | 6 ++++++ > > arch/powerpc/sysdev/xics/icp-native.c | 9 ++++++++- > > 3 files changed, 16 insertions(+), 1 deletion(-) > >=20 > > diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kerne= l/cpu_setup_power.S > > index 1557e7c..4673353 100644 > > --- a/arch/powerpc/kernel/cpu_setup_power.S > > +++ b/arch/powerpc/kernel/cpu_setup_power.S > > @@ -56,6 +56,7 @@ _GLOBAL(__setup_cpu_power8) > > li r0,0 > > mtspr SPRN_LPID,r0 > > mfspr r3,SPRN_LPCR > > + ori r3, r3, LPCR_PECEDH > > bl __init_LPCR > > bl __init_HFSCR > > bl __init_tlb_power8 > > @@ -74,6 +75,7 @@ _GLOBAL(__restore_cpu_power8) > > li r0,0 > > mtspr SPRN_LPID,r0 > > mfspr r3,SPRN_LPCR > > + ori r3, r3, LPCR_PECEDH > > bl __init_LPCR > > bl __init_HFSCR > > bl __init_tlb_power8 > > diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platfo= rms/powernv/smp.c > > index 0062a43..5fcfcf4 100644 > > --- a/arch/powerpc/platforms/powernv/smp.c > > +++ b/arch/powerpc/platforms/powernv/smp.c > > @@ -32,6 +32,7 @@ > > #include <asm/opal.h> > > #include <asm/runlatch.h> > > #include <asm/code-patching.h> > > +#include <asm/dbell.h> > > =20 > > #include "powernv.h" > > =20 > > @@ -46,6 +47,11 @@ static void pnv_smp_setup_cpu(int cpu) > > { > > if (cpu !=3D boot_cpuid) > > xics_setup_cpu(); > > + > > +#ifdef CONFIG_PPC_DOORBELL > > + if (cpu_has_feature(CPU_FTR_DBELL)) > > + doorbell_setup_this_cpu(); > > +#endif > > } >=20 > Where does CONFIG_PPC_DOORBELL get set? No where. > It looks like the only place you can be getting it is from CONFIG_PPC_PSE= RIES. > If you build a POWERNV only kernel it will get disabled, which I don't th= ink is > what we want. >=20 > I think we should select it for POWERNV as well as PSERIES. That would me= an > it's always enabled for any build of the files you touch, so you shouldn'= t need > the #ifdefs. Ok, I'll add and resend. Mikey ^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v2 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs 2014-06-04 8:03 ` Michael Ellerman 2014-06-04 9:38 ` Michael Neuling @ 2014-06-04 11:05 ` Michael Neuling 1 sibling, 0 replies; 7+ messages in thread From: Michael Neuling @ 2014-06-04 11:05 UTC (permalink / raw) To: Benjamin Herrenschmidt Cc: Preeti U Murthy, Paul Mackerras, linuxppc-dev, Anton Blanchard This patch enables POWER8 doorbell IPIs on powernv. Since doorbells can only IPI within a core, we test to see when we can use doorbells and if not we fall back to XICS. This also enables hypervisor doorbells to wakeup us up from nap/sleep via the LPCR PECEDH bit. Based on tests by Anton, the best case IPI latency between two threads drop= ped from 894ns to 512ns. Signed-off-by: Michael Neuling <mikey@neuling.org> --- v2: Adds select of PPC_DOORBELL for PSERIES and POWERNV as suggested by mpe. diff --git a/arch/powerpc/kernel/cpu_setup_power.S b/arch/powerpc/kernel/cp= u_setup_power.S index 1557e7c..4673353 100644 --- a/arch/powerpc/kernel/cpu_setup_power.S +++ b/arch/powerpc/kernel/cpu_setup_power.S @@ -56,6 +56,7 @@ _GLOBAL(__setup_cpu_power8) li r0,0 mtspr SPRN_LPID,r0 mfspr r3,SPRN_LPCR + ori r3, r3, LPCR_PECEDH bl __init_LPCR bl __init_HFSCR bl __init_tlb_power8 @@ -74,6 +75,7 @@ _GLOBAL(__restore_cpu_power8) li r0,0 mtspr SPRN_LPID,r0 mfspr r3,SPRN_LPCR + ori r3, r3, LPCR_PECEDH bl __init_LPCR bl __init_HFSCR bl __init_tlb_power8 diff --git a/arch/powerpc/platforms/powernv/Kconfig b/arch/powerpc/platform= s/powernv/Kconfig index c252ee9..45a8ed0 100644 --- a/arch/powerpc/platforms/powernv/Kconfig +++ b/arch/powerpc/platforms/powernv/Kconfig @@ -17,6 +17,7 @@ config PPC_POWERNV select CPU_FREQ_GOV_USERSPACE select CPU_FREQ_GOV_ONDEMAND select CPU_FREQ_GOV_CONSERVATIVE + select PPC_DOORBELL default y =20 config PPC_POWERNV_RTAS diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/= powernv/smp.c index 0062a43..5fcfcf4 100644 --- a/arch/powerpc/platforms/powernv/smp.c +++ b/arch/powerpc/platforms/powernv/smp.c @@ -32,6 +32,7 @@ #include <asm/opal.h> #include <asm/runlatch.h> #include <asm/code-patching.h> +#include <asm/dbell.h> =20 #include "powernv.h" =20 @@ -46,6 +47,11 @@ static void pnv_smp_setup_cpu(int cpu) { if (cpu !=3D boot_cpuid) xics_setup_cpu(); + +#ifdef CONFIG_PPC_DOORBELL + if (cpu_has_feature(CPU_FTR_DBELL)) + doorbell_setup_this_cpu(); +#endif } =20 int pnv_smp_kick_cpu(int nr) diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platform= s/pseries/Kconfig index 2cb8b77..756b482 100644 --- a/arch/powerpc/platforms/pseries/Kconfig +++ b/arch/powerpc/platforms/pseries/Kconfig @@ -21,6 +21,7 @@ config PPC_PSERIES select HAVE_CONTEXT_TRACKING select HOTPLUG_CPU if SMP select ARCH_RANDOM + select PPC_DOORBELL default y =20 config PPC_SPLPAR diff --git a/arch/powerpc/sysdev/xics/icp-native.c b/arch/powerpc/sysdev/xi= cs/icp-native.c index 9dee470..de8d948 100644 --- a/arch/powerpc/sysdev/xics/icp-native.c +++ b/arch/powerpc/sysdev/xics/icp-native.c @@ -26,6 +26,7 @@ #include <asm/errno.h> #include <asm/xics.h> #include <asm/kvm_ppc.h> +#include <asm/dbell.h> =20 struct icp_ipl { union { @@ -145,7 +146,13 @@ static unsigned int icp_native_get_irq(void) static void icp_native_cause_ipi(int cpu, unsigned long data) { kvmppc_set_host_ipi(cpu, 1); - icp_native_set_qirr(cpu, IPI_PRIORITY); +#ifdef CONFIG_PPC_DOORBELL + if (cpu_has_feature(CPU_FTR_DBELL) && + (cpumask_test_cpu(cpu, cpu_sibling_mask(smp_processor_id())))) + doorbell_cause_ipi(cpu, data); + else +#endif + icp_native_set_qirr(cpu, IPI_PRIORITY); } =20 void xics_wake_cpu(int cpu) ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry 2014-06-02 6:57 [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry Michael Neuling 2014-06-02 6:57 ` [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs Michael Neuling @ 2014-06-05 3:05 ` Preeti U Murthy 1 sibling, 0 replies; 7+ messages in thread From: Preeti U Murthy @ 2014-06-05 3:05 UTC (permalink / raw) To: Michael Neuling; +Cc: linuxppc-dev, Anton Blanchard, Paul Mackerras On 06/02/2014 12:27 PM, Michael Neuling wrote: > Currently when entering fastsleep we clear all LPCR PECE bits. > > This patch changes it to only clear the decrementer bit (ie. PECE1), which is > the only bit we really need to clear here. This is needed if we want to set > other wakeup causes like the PECEDH bit so we can use hypervisor doorbells on > powernv. > > Signed-off-by: Michael Neuling <mikey@neuling.org> > --- > drivers/cpuidle/cpuidle-powernv.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c > index 719f6fb..7f7798e 100644 > --- a/drivers/cpuidle/cpuidle-powernv.c > +++ b/drivers/cpuidle/cpuidle-powernv.c > @@ -73,7 +73,7 @@ static int fastsleep_loop(struct cpuidle_device *dev, > return index; > > new_lpcr = old_lpcr; > - new_lpcr &= ~(LPCR_MER | LPCR_PECE); /* lpcr[mer] must be 0 */ > + new_lpcr &= ~(LPCR_MER | LPCR_PECE1); /* lpcr[mer] must be 0 */ > > /* exit powersave upon external interrupt, but not decrementer > * interrupt. You might want to remove this comment and instead simply add /* Do not exit powersave upon decrementer interrupt */ Besides this, the following line which clears the wakeup from external interrupt bit can be removed as well, since we are not clearing it anyway ? new_lpcr |= LPCR_PECE0 ^^^ Regards Preeti U Murthy > ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2014-06-05 3:10 UTC | newest] Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2014-06-02 6:57 [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry Michael Neuling 2014-06-02 6:57 ` [PATCH 2/2] powerpc/powernv: Enable POWER8 doorbell IPIs Michael Neuling 2014-06-02 22:06 ` Anton Blanchard 2014-06-04 8:03 ` Michael Ellerman 2014-06-04 9:38 ` Michael Neuling 2014-06-04 11:05 ` [PATCH v2 " Michael Neuling 2014-06-05 3:05 ` [PATCH 1/2] powerpc/cpuidle: Only clear LPCR decrementer wakeup bit on fast sleep entry Preeti U Murthy
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).