powerpc/85xx: don't init the mpic ipi for the SoC which has doorbell support

It makes no sense to initialize the mpic ipi for the SoC which has
doorbell support. So set the smp_85xx_ops.probe to NULL for this
case. Since the smp_85xx_ops.probe is also used in function
smp_85xx_setup_cpu() to check if we need to invoke
mpic_setup_this_cpu(), we introduce a new setup_cpu function
smp_85xx_basic_setup() to remove this dependency.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Scott Wood <scottwood@freescale.com>

arch/powerpc/platforms/85xx/smp.c

@@ -389,15 +389,18 @@ static void mpc85xx_smp_machine_kexec(struct kimage *image)
 }
 #endif /* CONFIG_KEXEC */
 
-static void smp_85xx_setup_cpu(int cpu_nr)
+static void smp_85xx_basic_setup(int cpu_nr)
 {
-	if (smp_85xx_ops.probe == smp_mpic_probe)
-		mpic_setup_this_cpu();
-
 	if (cpu_has_feature(CPU_FTR_DBELL))
 		doorbell_setup_this_cpu();
 }
 
+static void smp_85xx_setup_cpu(int cpu_nr)
+{
+	mpic_setup_this_cpu();
+	smp_85xx_basic_setup(cpu_nr);
+}
+
 static const struct of_device_id mpc85xx_smp_guts_ids[] = {
 	{ .compatible = "fsl,mpc8572-guts", },
 	{ .compatible = "fsl,p1020-guts", },
@@ -412,13 +415,14 @@ void __init mpc85xx_smp_init(void)
 {
 	struct device_node *np;
 
-	smp_85xx_ops.setup_cpu = smp_85xx_setup_cpu;
 
 	np = of_find_node_by_type(NULL, "open-pic");
 	if (np) {
 		smp_85xx_ops.probe = smp_mpic_probe;
+		smp_85xx_ops.setup_cpu = smp_85xx_setup_cpu;
 		smp_85xx_ops.message_pass = smp_mpic_message_pass;
-	}
+	} else
+		smp_85xx_ops.setup_cpu = smp_85xx_basic_setup;
 
 	if (cpu_has_feature(CPU_FTR_DBELL)) {
 		/*
@@ -427,6 +431,7 @@ void __init mpc85xx_smp_init(void)
 		 */
 		smp_85xx_ops.message_pass = NULL;
 		smp_85xx_ops.cause_ipi = doorbell_cause_ipi;
+		smp_85xx_ops.probe = NULL;
 	}
 
 	np = of_find_matching_node(NULL, mpc85xx_smp_guts_ids);