of/address: Add support for 3 address cell bus

There's a few custom bus bindings (e.g. fsl,qoriq-mc) which use a
3 cell format with custom flags in the high cell. We can match these
buses as a fallback if we didn't match on PCI bus which is the only
standard bus binding with 3 address cells.

Link: https://lore.kernel.org/r/20230328-dt-address-helpers-v1-3-e2456c3e77ab@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>

drivers/of/address.c

@@ -95,11 +95,17 @@ static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
 	return 0;
 }
 
+static unsigned int of_bus_default_flags_get_flags(const __be32 *addr)
+{
+	return of_read_number(addr, 1);
+}
+
 static unsigned int of_bus_default_get_flags(const __be32 *addr)
 {
 	return IORESOURCE_MEM;
 }
 
+
 #ifdef CONFIG_PCI
 static unsigned int of_bus_pci_get_flags(const __be32 *addr)
 {
@@ -344,6 +350,11 @@ static unsigned int of_bus_isa_get_flags(const __be32 *addr)
 	return flags;
 }
 
+static int of_bus_default_flags_match(struct device_node *np)
+{
+	return of_bus_n_addr_cells(np) == 3;
+}
+
 /*
  * Array of bus specific translators
  */
@@ -373,6 +384,17 @@ static struct of_bus of_busses[] = {
 		.has_flags = true,
 		.get_flags = of_bus_isa_get_flags,
 	},
+	/* Default with flags cell */
+	{
+		.name = "default-flags",
+		.addresses = "reg",
+		.match = of_bus_default_flags_match,
+		.count_cells = of_bus_default_count_cells,
+		.map = of_bus_default_map,
+		.translate = of_bus_default_translate,
+		.has_flags = true,
+		.get_flags = of_bus_default_flags_get_flags,
+	},
 	/* Default */
 	{
 		.name = "default",

drivers/of/unittest-data/tests-address.dtsi

@@ -14,7 +14,7 @@ address-tests {
 			#size-cells = <1>;
 			/* ranges here is to make sure we don't use it for
 			 * dma-ranges translation */
-			ranges = <0x70000000 0x70000000 0x40000000>,
+			ranges = <0x70000000 0x70000000 0x50000000>,
 				 <0x00000000 0xd0000000 0x20000000>;
 			dma-ranges = <0x0 0x20000000 0x40000000>;
 
@@ -43,6 +43,13 @@ pci@90000000 {
 					     <0x42000000 0x0 0xc0000000 0x20000000 0x0 0x10000000>;
 			};
 
+			bus@a0000000 {
+				#address-cells = <3>;
+				#size-cells = <2>;
+				ranges = <0xf00baa 0x0 0x0 0xa0000000 0x0 0x100000>,
+					 <0xf00bee 0x1 0x0 0xb0000000 0x0 0x200000>;
+			};
+
 		};
 	};
 };

drivers/of/unittest.c

@@ -1048,7 +1048,7 @@ static void __init of_unittest_bus_ranges(void)
 			"for_each_of_range wrong flags on node %pOF flags=%x (expected %x)\n",
 			np, range.flags, IORESOURCE_MEM);
 		if (!i) {
-			unittest(range.size == 0x40000000,
+			unittest(range.size == 0x50000000,
 				 "for_each_of_range wrong size on node %pOF size=%llx\n",
 				 np, range.size);
 			unittest(range.cpu_addr == 0x70000000,
@@ -1074,6 +1074,61 @@ static void __init of_unittest_bus_ranges(void)
 	of_node_put(np);
 }
 
+static void __init of_unittest_bus_3cell_ranges(void)
+{
+	struct device_node *np;
+	struct of_range range;
+	struct of_range_parser parser;
+	int i = 0;
+
+	np = of_find_node_by_path("/testcase-data/address-tests/bus@a0000000");
+	if (!np) {
+		pr_err("missing testcase data\n");
+		return;
+	}
+
+	if (of_range_parser_init(&parser, np)) {
+		pr_err("missing ranges property\n");
+		return;
+	}
+
+	/*
+	 * Get the "ranges" from the device tree
+	 */
+	for_each_of_range(&parser, &range) {
+		if (!i) {
+			unittest(range.flags == 0xf00baa,
+				 "for_each_of_range wrong flags on node %pOF flags=%x\n",
+				 np, range.flags);
+			unittest(range.size == 0x100000,
+				 "for_each_of_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0xa0000000,
+				 "for_each_of_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.bus_addr == 0x0,
+				 "for_each_of_range wrong bus addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		} else {
+			unittest(range.flags == 0xf00bee,
+				 "for_each_of_range wrong flags on node %pOF flags=%x\n",
+				 np, range.flags);
+			unittest(range.size == 0x200000,
+				 "for_each_of_range wrong size on node %pOF size=%llx\n",
+				 np, range.size);
+			unittest(range.cpu_addr == 0xb0000000,
+				 "for_each_of_range wrong CPU addr (%llx) on node %pOF",
+				 range.cpu_addr, np);
+			unittest(range.bus_addr == 0x100000000,
+				 "for_each_of_range wrong bus addr (%llx) on node %pOF",
+				 range.pci_addr, np);
+		}
+		i++;
+	}
+
+	of_node_put(np);
+}
+
 static void __init of_unittest_parse_interrupts(void)
 {
 	struct device_node *np;
@@ -3711,6 +3766,7 @@ static int __init of_unittest(void)
 	of_unittest_parse_dma_ranges();
 	of_unittest_pci_dma_ranges();
 	of_unittest_bus_ranges();
+	of_unittest_bus_3cell_ranges();
 	of_unittest_match_node();
 	of_unittest_platform_populate();
 	of_unittest_overlay();