diff options
| -rw-r--r-- | arch/powerpc/platforms/powernv/idle.c | 34 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/smp.c | 8 |
2 files changed, 33 insertions, 9 deletions
diff --git a/arch/powerpc/platforms/powernv/idle.c b/arch/powerpc/platforms/powernv/idle.c index 2abee070373f..a1296e72cd2e 100644 --- a/arch/powerpc/platforms/powernv/idle.c +++ b/arch/powerpc/platforms/powernv/idle.c @@ -68,7 +68,7 @@ static int pnv_save_sprs_for_deep_states(void) * all cpus at boot. Get these reg values of current cpu and use the * same across all cpus. */ - uint64_t lpcr_val = mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1; + uint64_t lpcr_val = mfspr(SPRN_LPCR); uint64_t hid0_val = mfspr(SPRN_HID0); uint64_t hid1_val = mfspr(SPRN_HID1); uint64_t hid4_val = mfspr(SPRN_HID4); @@ -355,6 +355,14 @@ void power9_idle(void) } #ifdef CONFIG_HOTPLUG_CPU +static void pnv_program_cpu_hotplug_lpcr(unsigned int cpu, u64 lpcr_val) +{ + u64 pir = get_hard_smp_processor_id(cpu); + + mtspr(SPRN_LPCR, lpcr_val); + opal_slw_set_reg(pir, SPRN_LPCR, lpcr_val); +} + /* * pnv_cpu_offline: A function that puts the CPU into the deepest * available platform idle state on a CPU-Offline. @@ -364,6 +372,20 @@ unsigned long pnv_cpu_offline(unsigned int cpu) { unsigned long srr1; u32 idle_states = pnv_get_supported_cpuidle_states(); + u64 lpcr_val; + + /* + * We don't want to take decrementer interrupts while we are + * offline, so clear LPCR:PECE1. We keep PECE2 (and + * LPCR_PECE_HVEE on P9) enabled as to let IPIs in. + * + * If the CPU gets woken up by a special wakeup, ensure that + * the SLW engine sets LPCR with decrementer bit cleared, else + * the CPU will come back to the kernel due to a spurious + * wakeup. + */ + lpcr_val = mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1; + pnv_program_cpu_hotplug_lpcr(cpu, lpcr_val); __ppc64_runlatch_off(); @@ -394,6 +416,16 @@ unsigned long pnv_cpu_offline(unsigned int cpu) __ppc64_runlatch_on(); + /* + * Re-enable decrementer interrupts in LPCR. + * + * Further, we want stop states to be woken up by decrementer + * for non-hotplug cases. So program the LPCR via stop api as + * well. + */ + lpcr_val = mfspr(SPRN_LPCR) | (u64)LPCR_PECE1; + pnv_program_cpu_hotplug_lpcr(cpu, lpcr_val); + return srr1; } #endif diff --git a/arch/powerpc/platforms/powernv/smp.c b/arch/powerpc/platforms/powernv/smp.c index c6448c7aabe7..c17f81e433f7 100644 --- a/arch/powerpc/platforms/powernv/smp.c +++ b/arch/powerpc/platforms/powernv/smp.c @@ -165,12 +165,6 @@ static void pnv_smp_cpu_kill_self(void) if (cpu_has_feature(CPU_FTR_ARCH_207S)) wmask = SRR1_WAKEMASK_P8; - /* We don't want to take decrementer interrupts while we are offline, - * so clear LPCR:PECE1. We keep PECE2 (and LPCR_PECE_HVEE on P9) - * enabled as to let IPIs in. - */ - mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~(u64)LPCR_PECE1); - while (!generic_check_cpu_restart(cpu)) { /* * Clear IPI flag, since we don't handle IPIs while @@ -220,8 +214,6 @@ static void pnv_smp_cpu_kill_self(void) } - /* Re-enable decrementer interrupts */ - mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1); DBG("CPU%d coming online...\n", cpu); } |