of_address: Add bus type match for pci ranges parser

So the parser can be used to parse range property of ISA bus.

As they're all using PCI-like method of range property, there is no need
start a new parser.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Author: FlyGoat

drivers/of/address.c

@@ -49,6 +49,7 @@ struct of_bus {
 	u64		(*map)(__be32 *addr, const __be32 *range,
 				int na, int ns, int pna);
 	int		(*translate)(__be32 *addr, u64 offset, int na);
+	bool	has_flags;
 	unsigned int	(*get_flags)(const __be32 *addr);
 };
 
@@ -364,6 +365,7 @@ static struct of_bus of_busses[] = {
 		.count_cells = of_bus_pci_count_cells,
 		.map = of_bus_pci_map,
 		.translate = of_bus_pci_translate,
+		.has_flags = true,
 		.get_flags = of_bus_pci_get_flags,
 	},
 #endif /* CONFIG_PCI */
@@ -375,6 +377,7 @@ static struct of_bus of_busses[] = {
 		.count_cells = of_bus_isa_count_cells,
 		.map = of_bus_isa_map,
 		.translate = of_bus_isa_translate,
+		.has_flags = true,
 		.get_flags = of_bus_isa_get_flags,
 	},
 	/* Default */
@@ -698,9 +701,10 @@ static int parser_init(struct of_pci_range_parser *parser,
 
 	parser->node = node;
 	parser->pna = of_n_addr_cells(node);
-	parser->na = of_bus_n_addr_cells(node);
-	parser->ns = of_bus_n_size_cells(node);
 	parser->dma = !strcmp(name, "dma-ranges");
+	parser->bus = of_match_bus(node);
+
+	parser->bus->count_cells(parser->node, &parser->na, &parser->ns);
 
 	parser->range = of_get_property(node, name, &rlen);
 	if (parser->range == NULL)
@@ -732,19 +736,21 @@ struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
 	int na = parser->na;
 	int ns = parser->ns;
 	int np = parser->pna + na + ns;
+	int busflag_na = 0;
 
 	if (!range)
 		return NULL;
 
 	if (!parser->range || parser->range + np > parser->end)
 		return NULL;
 
-	if (parser->na == 3)
-		range->flags = of_bus_pci_get_flags(parser->range);
-	else
-		range->flags = 0;
+	range->flags = parser->bus->get_flags(parser->range);
+
+	/* A extra cell for resource flags */
+	if (parser->bus->has_flags)
+		busflag_na = 1;
 
-	range->pci_addr = of_read_number(parser->range, na);
+	range->bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
 
 	if (parser->dma)
 		range->cpu_addr = of_translate_dma_address(parser->node,
@@ -759,11 +765,10 @@ struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
 	/* Now consume following elements while they are contiguous */
 	while (parser->range + np <= parser->end) {
 		u32 flags = 0;
-		u64 pci_addr, cpu_addr, size;
+		u64 bus_addr, cpu_addr, size;
 
-		if (parser->na == 3)
-			flags = of_bus_pci_get_flags(parser->range);
-		pci_addr = of_read_number(parser->range, na);
+		flags = parser->bus->get_flags(parser->range);
+		bus_addr = of_read_number(parser->range + busflag_na, na - busflag_na);
 		if (parser->dma)
 			cpu_addr = of_translate_dma_address(parser->node,
 					parser->range + na);
@@ -774,7 +779,7 @@ struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser,
 
 		if (flags != range->flags)
 			break;
-		if (pci_addr != range->pci_addr + range->size ||
+		if (bus_addr != range->bus_addr + range->size ||
 		    cpu_addr != range->cpu_addr + range->size)
 			break;
 

include/linux/of_address.h

@@ -6,8 +6,11 @@
 #include <linux/of.h>
 #include <linux/io.h>
 
+struct of_bus;
+
 struct of_pci_range_parser {
 	struct device_node *node;
+	struct of_bus *bus;
 	const __be32 *range;
 	const __be32 *end;
 	int na;
@@ -119,6 +122,7 @@ static inline void __iomem *of_iomap(struct device_node *device, int index)
 	return NULL;
 }
 #endif
+#define of_range_parser_init of_pci_range_parser_init
 
 #if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_PCI)
 extern const __be32 *of_get_pci_address(struct device_node *dev, int bar_no,