In order to enable a CPU to be power managed through its PM domain, let's
try to attach it by calling psci_dt_attach_cpu() during the cpuidle
initialization.

psci_dt_attach_cpu() returns a pointer to the attached struct device, which
later should be used for runtime PM, hence we need to store it somewhere.
Rather than adding yet another per CPU variable, let's create a per CPU
struct to collect the relevant per CPU variables.

Signed-off-by: Ulf Hansson <redacted>
---
 drivers/cpuidle/cpuidle-psci.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c
index a16467daf99d..1510422c7a53 100644
--- a/drivers/cpuidle/cpuidle-psci.c
+++ b/drivers/cpuidle/cpuidle-psci.c

@@ -23,7 +23,12 @@
 #include "cpuidle-psci.h"
 #include "dt_idle_states.h"

-static DEFINE_PER_CPU_READ_MOSTLY(u32 *, psci_power_state);
+struct psci_cpuidle_data {
+	u32 *psci_states;
+	struct device *dev;
+};
+
+static DEFINE_PER_CPU_READ_MOSTLY(struct psci_cpuidle_data, psci_cpuidle_data);
 static DEFINE_PER_CPU(u32, domain_state);