int smp_generic_kick_cpu(int nr)
{
if (nr < 0 || nr >= nr_cpu_ids)
return -EINVAL;
/*
* The processor is currently spinning, waiting for the
* cpu_start field to become non-zero After we set cpu_start,
* the processor will continue on to secondary_start
*/
if (!paca[nr].cpu_start) {
paca[nr].cpu_start = 1;
smp_mb();
return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
/*
* Ok it's not there, so it might be soft-unplugged, let's
* try to bring it back
*/
generic_set_cpu_up(nr);
smp_wmb();
smp_send_reschedule(nr);
#endif /* CONFIG_HOTPLUG_CPU */
return 0;
}
static int __cpuinit smp_85xx_kick_cpu(int nr)
{
unsigned long flags;
const u64 *cpu_rel_addr;
__iomem struct epapr_spin_table *spin_table;
struct device_node *np;
int hw_cpu = get_hard_smp_processor_id(nr);
int ioremappable;
int ret = 0;
WARN_ON(nr < 0 || nr >= NR_CPUS);
WARN_ON(hw_cpu < 0 || hw_cpu >= NR_CPUS);
pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
np = of_get_cpu_node(nr, NULL);
cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
if (cpu_rel_addr == NULL) {
printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
return -ENOENT;
}
/*
* A secondary core could be in a spinloop in the bootpage
* (0xfffff000), somewhere in highmem, or somewhere in lowmem.
* The bootpage and highmem can be accessed via ioremap(), but
* we need to directly access the spinloop if its in lowmem.
*/
ioremappable = *cpu_rel_addr > virt_to_phys(high_memory);
/* Map the spin table */
if (ioremappable)
spin_table = ioremap(*cpu_rel_addr,
sizeof(struct epapr_spin_table));
else
spin_table = phys_to_virt(*cpu_rel_addr);
local_irq_save(flags);
#ifdef CONFIG_PPC32
#ifdef CONFIG_HOTPLUG_CPU
/* Corresponding to generic_set_cpu_dead() */
generic_set_cpu_up(nr);
if (system_state == SYSTEM_RUNNING) {
out_be32(&spin_table->addr_l, 0);
/*
* We don't set the BPTR register here since it already points
* to the boot page properly.
*/
mpic_reset_core(hw_cpu);
/* wait until core is ready... */
if (!spin_event_timeout(in_be32(&spin_table->addr_l) == 1,
10000, 100)) {
pr_err("%s: timeout waiting for core %d to reset\n",
__func__, hw_cpu);
ret = -ENOENT;
goto out;
}
/* clear the acknowledge status */
__secondary_hold_acknowledge = -1;
}
#endif
out_be32(&spin_table->pir, hw_cpu);
out_be32(&spin_table->addr_l, __pa(__early_start));
if (!ioremappable)
flush_dcache_range((ulong)spin_table,
(ulong)spin_table + sizeof(struct epapr_spin_table));
/* Wait a bit for the CPU to ack. */
if (!spin_event_timeout(__secondary_hold_acknowledge == hw_cpu,
10000, 100)) {
pr_err("%s: timeout waiting for core %d to ack\n",
__func__, hw_cpu);
ret = -ENOENT;
goto out;
}
out:
#else
smp_generic_kick_cpu(nr);
out_be32(&spin_table->pir, hw_cpu);
out_be64((u64 *)(&spin_table->addr_h),
__pa((u64)*((unsigned long long *)generic_secondary_smp_init)));
if (!ioremappable)
flush_dcache_range((ulong)spin_table,
(ulong)spin_table + sizeof(struct epapr_spin_table));
#endif
local_irq_restore(flags);
if (ioremappable)
iounmap(spin_table);
return ret;
}
