diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/smp.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/smp.c | 50 |
1 files changed, 44 insertions, 6 deletions
diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c index 4753958cd509..fc34025ef822 100644 --- a/arch/powerpc/platforms/powernv/smp.c +++ b/arch/powerpc/platforms/powernv/smp.c @@ -149,6 +149,8 @@ static int pnv_smp_cpu_disable(void) static void pnv_smp_cpu_kill_self(void) { unsigned int cpu; + unsigned long srr1; + u32 idle_states; /* Standard hot unplug procedure */ local_irq_disable(); @@ -159,19 +161,41 @@ static void pnv_smp_cpu_kill_self(void) generic_set_cpu_dead(cpu); smp_wmb(); + idle_states = pnv_get_supported_cpuidle_states(); /* We don't want to take decrementer interrupts while we are offline, * so clear LPCR:PECE1. We keep PECE2 enabled. */ mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1); while (!generic_check_cpu_restart(cpu)) { + ppc64_runlatch_off(); - power7_nap(1); + + if (idle_states & OPAL_PM_WINKLE_ENABLED) + srr1 = power7_winkle(); + else if ((idle_states & OPAL_PM_SLEEP_ENABLED) || + (idle_states & OPAL_PM_SLEEP_ENABLED_ER1)) + srr1 = power7_sleep(); + else + srr1 = power7_nap(1); + ppc64_runlatch_on(); - /* Clear the IPI that woke us up */ - icp_native_flush_interrupt(); - local_paca->irq_happened &= PACA_IRQ_HARD_DIS; - mb(); + /* + * If the SRR1 value indicates that we woke up due to + * an external interrupt, then clear the interrupt. + * We clear the interrupt before checking for the + * reason, so as to avoid a race where we wake up for + * some other reason, find nothing and clear the interrupt + * just as some other cpu is sending us an interrupt. + * If we returned from power7_nap as a result of + * having finished executing in a KVM guest, then srr1 + * contains 0. + */ + if ((srr1 & SRR1_WAKEMASK) == SRR1_WAKEEE) { + icp_native_flush_interrupt(); + local_paca->irq_happened &= PACA_IRQ_HARD_DIS; + smp_mb(); + } if (cpu_core_split_required()) continue; @@ -185,13 +209,27 @@ static void pnv_smp_cpu_kill_self(void) #endif /* CONFIG_HOTPLUG_CPU */ +static int pnv_cpu_bootable(unsigned int nr) +{ + /* + * Starting with POWER8, the subcore logic relies on all threads of a + * core being booted so that they can participate in split mode + * switches. So on those machines we ignore the smt_enabled_at_boot + * setting (smt-enabled on the kernel command line). + */ + if (cpu_has_feature(CPU_FTR_ARCH_207S)) + return 1; + + return smp_generic_cpu_bootable(nr); +} + static struct smp_ops_t pnv_smp_ops = { .message_pass = smp_muxed_ipi_message_pass, .cause_ipi = NULL, /* Filled at runtime by xics_smp_probe() */ .probe = xics_smp_probe, .kick_cpu = pnv_smp_kick_cpu, .setup_cpu = pnv_smp_setup_cpu, - .cpu_bootable = smp_generic_cpu_bootable, + .cpu_bootable = pnv_cpu_bootable, #ifdef CONFIG_HOTPLUG_CPU .cpu_disable = pnv_smp_cpu_disable, .cpu_die = generic_cpu_die, |