void __init arch_get_fast_and_slow_cpus(struct cpumask *fast,
struct cpumask *slow)
{
struct device_node *cn = NULL;
int cpu;
cpumask_clear(fast);
cpumask_clear(slow);
/*
* Use the config options if they are given. This helps testing
* HMP scheduling on systems without a big.LITTLE architecture.
*/
if (strlen(CONFIG_HMP_FAST_CPU_MASK) && strlen(CONFIG_HMP_SLOW_CPU_MASK)) {
if (cpulist_parse(CONFIG_HMP_FAST_CPU_MASK, fast))
WARN(1, "Failed to parse HMP fast cpu mask!\n");
if (cpulist_parse(CONFIG_HMP_SLOW_CPU_MASK, slow))
WARN(1, "Failed to parse HMP slow cpu mask!\n");
return;
}
/*
* Else, parse device tree for little cores.
*/
while ((cn = of_find_node_by_type(cn, "cpu"))) {
const u32 *mpidr;
int len;
mpidr = of_get_property(cn, "reg", &len);
if (!mpidr || len != 4) {
pr_err("* %s missing reg property\n", cn->full_name);
continue;
}
cpu = get_logical_index(be32_to_cpup(mpidr));
if (cpu == -EINVAL) {
pr_err("couldn't get logical index for mpidr %x\n",
be32_to_cpup(mpidr));
break;
}
if (is_little_cpu(cn))
cpumask_set_cpu(cpu, slow);
else
cpumask_set_cpu(cpu, fast);
}
if (!cpumask_empty(fast) && !cpumask_empty(slow))
return;
/*
* We didn't find both big and little cores so let's call all cores
* fast as this will keep the system running, with all cores being
* treated equal.
*/
cpumask_setall(fast);
cpumask_clear(slow);
}
static unsigned int get_num_unloaded_little_cpus(void)
{
unsigned int cpu;
unsigned int unloaded_cpus = 0;
for_each_online_cpu(cpu) {
if (is_little_cpu(cpu)) {
unsigned int cpu_load = get_delta_cpu_load_and_update(cpu);
if (cpu_load < load_threshold_down)
unloaded_cpus += 1;
}
}
return unloaded_cpus;
}
static void __ref enable_little_cluster(void)
{
unsigned int cpu;
unsigned int num_up = 0;
for_each_present_cpu(cpu) {
if (is_little_cpu(cpu) && !cpu_online(cpu)) {
cpu_up(cpu);
num_up++;
}
}
if (!little_cluster_enabled)
pr_info("cluster_plug: %d little cpus enabled\n", num_up);
little_cluster_enabled = true;
}
static void disable_little_cluster(void)
{
unsigned int cpu;
unsigned int num_down = 0;
if (!little_cluster_enabled)
return;
for_each_present_cpu(cpu) {
if (is_little_cpu(cpu) && cpu_online(cpu)) {
cpu_down(cpu);
num_down++;
}
}
pr_info("cluster_plug: %d little cpus disabled\n", num_down);
little_cluster_enabled = false;
}
