On Monday 13 February 2023 20:08:52 Christophe Leroy wrote:

Le 24/12/2022 à 22:14, Pali Rohár a écrit :

quoted

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>
---
  arch/powerpc/platforms/85xx/p2020.c | 83 +++++++----------------------
  1 file changed, 19 insertions(+), 64 deletions(-)

diff --git a/arch/powerpc/platforms/85xx/p2020.c b/arch/powerpc/platforms/85xx/p2020.c
index adf3750abef9..b3fb600e1d83 100644
--- a/arch/powerpc/platforms/85xx/p2020.c
+++ b/arch/powerpc/platforms/85xx/p2020.c

@@ -156,83 +156,38 @@ static void __init p2020_setup_arch(void)
  #endif
  }
  
-#ifdef CONFIG_MPC85xx_DS
-machine_arch_initcall(p2020_ds, mpc85xx_common_publish_devices);
-#endif /* CONFIG_MPC85xx_DS */
-
-#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 */
+machine_arch_initcall(p2020, mpc85xx_common_publish_devices);
  
  /*
   * Called very early, device-tree isn't unflattened
   */
-#ifdef CONFIG_MPC85xx_DS
-static int __init p2020_ds_probe(void)
-{
-	return !!of_machine_is_compatible("fsl,P2020DS");
-}
-#endif /* CONFIG_MPC85xx_DS */
-
-#ifdef CONFIG_MPC85xx_RDB
-static int __init p2020_rdb_probe(void)
-{
-	if (of_machine_is_compatible("fsl,P2020RDB"))
-		return 1;
-	return 0;
-}
-
-static int __init p2020_rdb_pc_probe(void)
+static int __init p2020_probe(void)
  {
-	if (of_machine_is_compatible("fsl,P2020RDB-PC"))
-		return 1;
-	return 0;
+	struct device_node *p2020_cpu;
+
+	/*
+	 * 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");
+	if (!p2020_cpu)
+		return 0;
+
+	of_node_put(p2020_cpu);

of_node_put() already checks for nullity of its parameter, so you can 
simplify stuff here, something like

	p2020_cpu = of_find_node_by_path("/cpus/PowerPC,P2020@0");
	of_node_put(p2020_cpu);

	return !!p2020_cpu;

Ok!

quoted

+	return 1;
  }
-#endif /* CONFIG_MPC85xx_RDB */
-
-#ifdef CONFIG_MPC85xx_DS
-define_machine(p2020_ds) {
-	.name			= "P2020 DS",
-	.probe			= p2020_ds_probe,
-	.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,
-	.calibrate_decr		= generic_calibrate_decr,
-	.progress		= udbg_progress,
-};
-#endif /* CONFIG_MPC85xx_DS */
-
-#ifdef CONFIG_MPC85xx_RDB
-define_machine(p2020_rdb) {
-	.name			= "P2020 RDB",
-	.probe			= p2020_rdb_probe,
-	.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,
-	.calibrate_decr		= generic_calibrate_decr,
-	.progress		= udbg_progress,
-};
  
-define_machine(p2020_rdb_pc) {
-	.name			= "P2020RDB-PC",
-	.probe			= p2020_rdb_pc_probe,
+define_machine(p2020) {
+	.name			= "Freescale P2020",
+	.probe			= p2020_probe,
  	.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,
+	.pcibios_fixup_phb	= fsl_pcibios_fixup_phb,
  #endif
  	.get_irq		= mpic_get_irq,
  	.calibrate_decr		= generic_calibrate_decr,
  	.progress		= udbg_progress,
  };
-#endif /* CONFIG_MPC85xx_RDB */