powerpc/85xx: p2020: Define just one machine description

Combine machine descriptions and code of all P2020 boards into just one
generic unified P2020 machine description. This allows kernel to boot on
any P2020-based board with P2020 DTS file without need to patch kernel and
define a new machine description in 85xx powerpc platform directory.
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230408140122.25293-12-pali@kernel.org

arch/powerpc/platforms/85xx/p2020.c

@@ -47,47 +47,29 @@ static void __init p2020_setup_arch(void)
 	mpc85xx_qe_par_io_init();
 }
 
-#ifdef CONFIG_MPC85xx_DS
-machine_arch_initcall(p2020_ds, mpc85xx_common_publish_devices);
-#endif /* CONFIG_MPC85xx_DS */
+/*
+ * Called very early, device-tree isn't unflattened
+ */
+static int __init p2020_probe(void)
+{
+	struct device_node *p2020_cpu;
 
-#ifdef CONFIG_MPC85xx_RDB
-machine_arch_initcall(p2020_rdb, mpc85xx_common_publish_devices);
-machine_arch_initcall(p2020_rdb_pc, mpc85xx_common_publish_devices);
-#endif /* CONFIG_MPC85xx_RDB */
+	/*
+	 * There is no common compatible string for all P2020 boards.
+	 * The only common thing is "PowerPC,P2020@0" cpu node.
+	 * So check for P2020 board via this cpu node.
+	 */
+	p2020_cpu = of_find_node_by_path("/cpus/PowerPC,P2020@0");
+	of_node_put(p2020_cpu);
 
-#ifdef CONFIG_MPC85xx_DS
-define_machine(p2020_ds) {
-	.name			= "P2020 DS",
-	.compatible		= "fsl,P2020DS",
-	.setup_arch		= p2020_setup_arch,
-	.init_IRQ		= p2020_pic_init,
-#ifdef CONFIG_PCI
-	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
-	.pcibios_fixup_phb	= fsl_pcibios_fixup_phb,
-#endif
-	.get_irq		= mpic_get_irq,
-	.progress		= udbg_progress,
-};
-#endif /* CONFIG_MPC85xx_DS */
+	return !!p2020_cpu;
+}
 
-#ifdef CONFIG_MPC85xx_RDB
-define_machine(p2020_rdb) {
-	.name			= "P2020 RDB",
-	.compatible		= "fsl,P2020RDB",
-	.setup_arch		= p2020_setup_arch,
-	.init_IRQ		= p2020_pic_init,
-#ifdef CONFIG_PCI
-	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
-	.pcibios_fixup_phb	= fsl_pcibios_fixup_phb,
-#endif
-	.get_irq		= mpic_get_irq,
-	.progress		= udbg_progress,
-};
+machine_arch_initcall(p2020, mpc85xx_common_publish_devices);
 
-define_machine(p2020_rdb_pc) {
-	.name			= "P2020RDB-PC",
-	.compatible		= "fsl,P2020RDB-PC",
+define_machine(p2020) {
+	.name			= "Freescale P2020",
+	.probe			= p2020_probe,
 	.setup_arch		= p2020_setup_arch,
 	.init_IRQ		= p2020_pic_init,
 #ifdef CONFIG_PCI
@@ -97,4 +79,3 @@ define_machine(p2020_rdb_pc) {
 	.get_irq		= mpic_get_irq,
 	.progress		= udbg_progress,
 };
-#endif /* CONFIG_MPC85xx_RDB */