static void pnv_smp_cpu_kill_self(void)
{
unsigned int cpu;
/* Standard hot unplug procedure */
local_irq_disable();
idle_task_exit();
current->active_mm = NULL; /* for sanity */
cpu = smp_processor_id();
DBG("CPU%d offline\n", cpu);
generic_set_cpu_dead(cpu);
smp_wmb();
/* 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)) {
power7_nap();
if (!generic_check_cpu_restart(cpu)) {
DBG("CPU%d Unexpected exit while offline !\n", cpu);
/* We may be getting an IPI, so we re-enable
* interrupts to process it, it will be ignored
* since we aren't online (hopefully)
*/
local_irq_enable();
local_irq_disable();
}
}
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);
DBG("CPU%d coming online...\n", cpu);
}
static void pnv_smp_cpu_kill_self(void)
{
unsigned int cpu;
/* Standard hot unplug procedure */
local_irq_disable();
idle_task_exit();
current->active_mm = NULL; /* for sanity */
cpu = smp_processor_id();
DBG("CPU%d offline\n", cpu);
generic_set_cpu_dead(cpu);
smp_wmb();
/* 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);
ppc64_runlatch_on();
/* Reenable IRQs briefly to clear the IPI that woke us */
local_irq_enable();
local_irq_disable();
mb();
if (cpu_core_split_required())
continue;
if (!generic_check_cpu_restart(cpu))
DBG("CPU%d Unexpected exit while offline !\n", cpu);
}
mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_PECE1);
DBG("CPU%d coming online...\n", cpu);
}
/*
* pnv_cpu_offline: A function that puts the CPU into the deepest
* available platform idle state on a CPU-Offline.
* interrupts hard disabled and no lazy irq pending.
*/
unsigned long pnv_cpu_offline(unsigned int cpu)
{
unsigned long srr1;
u32 idle_states = pnv_get_supported_cpuidle_states();
__ppc64_runlatch_off();
if (cpu_has_feature(CPU_FTR_ARCH_300) && deepest_stop_found) {
unsigned long psscr;
psscr = mfspr(SPRN_PSSCR);
psscr = (psscr & ~pnv_deepest_stop_psscr_mask) |
pnv_deepest_stop_psscr_val;
srr1 = power9_idle_stop(psscr);
} else if (idle_states & OPAL_PM_WINKLE_ENABLED) {
srr1 = power7_idle_insn(PNV_THREAD_WINKLE);
} else if ((idle_states & OPAL_PM_SLEEP_ENABLED) ||
(idle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
srr1 = power7_idle_insn(PNV_THREAD_SLEEP);
} else if (idle_states & OPAL_PM_NAP_ENABLED) {
srr1 = power7_idle_insn(PNV_THREAD_NAP);
} else {
/* This is the fallback method. We emulate snooze */
while (!generic_check_cpu_restart(cpu)) {
HMT_low();
HMT_very_low();
}
srr1 = 0;
HMT_medium();
}
__ppc64_runlatch_on();
return srr1;
}
/*
* pnv_cpu_offline: A function that puts the CPU into the deepest
* available platform idle state on a CPU-Offline.
* interrupts hard disabled and no lazy irq pending.
*/
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();
if (cpu_has_feature(CPU_FTR_ARCH_300) && deepest_stop_found) {
unsigned long psscr;
psscr = mfspr(SPRN_PSSCR);
psscr = (psscr & ~pnv_deepest_stop_psscr_mask) |
pnv_deepest_stop_psscr_val;
srr1 = power9_offline_stop(psscr);
} else if ((idle_states & OPAL_PM_WINKLE_ENABLED) &&
(idle_states & OPAL_PM_LOSE_FULL_CONTEXT)) {
srr1 = power7_idle_insn(PNV_THREAD_WINKLE);
} else if ((idle_states & OPAL_PM_SLEEP_ENABLED) ||
(idle_states & OPAL_PM_SLEEP_ENABLED_ER1)) {
srr1 = power7_idle_insn(PNV_THREAD_SLEEP);
} else if (idle_states & OPAL_PM_NAP_ENABLED) {
srr1 = power7_idle_insn(PNV_THREAD_NAP);
} else {
/* This is the fallback method. We emulate snooze */
while (!generic_check_cpu_restart(cpu)) {
HMT_low();
HMT_very_low();
}
srr1 = 0;
HMT_medium();
}
__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;
}
