of: Workaround missing '#{address,size}-cells' properties [drop v6.13 + 2]

The dcp and dcpext nodes are missing '#address-cells' and '#size-cells'
properties expected for busses. The nodes are handled as bus since they
contain the 'piodma' subdevice. Commit 6e5773d ("of/address: Fix
WARN when attempting translating non-translatable addresses") triggers
an oops while evaluating reserved memory in dart. Commit 045b14c
("of: WARN on deprecated #address-cells/#size-cells handling") triggers
warnings in the same code path.

Happens only on devices with reserved memory for the piodma device
(should be dcp/dcp0 only).

Signed-off-by: Janne Grunau <j@jannau.net>

Author: jannau

drivers/of/address.c

@@ -342,6 +342,15 @@ static int of_bus_default_flags_match(struct device_node *np)
 
 static int of_bus_default_match(struct device_node *np)
 {
+	/**
+	 * To avoid issues with "missing" '#{address,size}-cells' properties
+	 * in dcp/dcpext nodes while evaluatting the 'piodma' sub device.
+	 * Keep this at least until v6.13 + 2 to ensure fixed devicetrees are
+	 * deployed.
+	 */
+	if (of_device_is_compatible(np, "apple,dcp") ||
+		of_device_is_compatible(np, "apple,dcpext"))
+		return true;
 	/*
 	 * Check for presence first since of_bus_n_addr_cells() will warn when
 	 * walking parent nodes.

drivers/of/base.c

@@ -89,6 +89,8 @@ static bool __of_node_is_type(const struct device_node *np, const char *type)
 
 #define EXCLUDED_DEFAULT_CELLS_PLATFORMS ( \
 	IS_ENABLED(CONFIG_SPARC) || \
+	of_find_compatible_node(NULL, NULL, "apple,dcp") || \
+	of_find_compatible_node(NULL, NULL, "apple,dcpext") || \
 	of_find_compatible_node(NULL, NULL, "coreboot") \
 )