arm64: kernel: enable PSCI cpu operations on UP systems

PSCI CPU operations have to be enabled on UP kernels so that calls
like eg cpu_suspend can be made functional on UP too.

This patch reworks the PSCI CPU operations so that they can be
enabled on UP systems.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

arch/arm64/kernel/cpu_ops.c

@@ -30,8 +30,8 @@ const struct cpu_operations *cpu_ops[NR_CPUS];
 static const struct cpu_operations *supported_cpu_ops[] __initconst = {
 #ifdef CONFIG_SMP
 	&smp_spin_table_ops,
-	&cpu_psci_ops,
 #endif
+	&cpu_psci_ops,
 	NULL,
 };
 

arch/arm64/kernel/psci.c

@@ -434,9 +434,11 @@ static int cpu_psci_cpu_kill(unsigned int cpu)
 	return 0;
 }
 #endif
+#endif
 
 const struct cpu_operations cpu_psci_ops = {
 	.name		= "psci",
+#ifdef CONFIG_SMP
 	.cpu_init	= cpu_psci_cpu_init,
 	.cpu_prepare	= cpu_psci_cpu_prepare,
 	.cpu_boot	= cpu_psci_cpu_boot,
@@ -445,6 +447,6 @@ const struct cpu_operations cpu_psci_ops = {
 	.cpu_die	= cpu_psci_cpu_die,
 	.cpu_kill	= cpu_psci_cpu_kill,
 #endif
+#endif
 };
 
-#endif