From: Andrew Murray Date: Thu, 16 May 2013 15:55:17 +0000 (+0200) Subject: of/pci: Provide support for parsing PCI DT ranges property X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=29b635c00f3ebcdaf7a52c4948f6d948ad3757d3;p=linux-beck.git of/pci: Provide support for parsing PCI DT ranges property This patch factors out common implementation patterns to reduce overall kernel code and provide a means for host bridge drivers to directly obtain struct resources from the DT's ranges property without relying on architecture specific DT handling. This will make it easier to write archiecture independent host bridge drivers and mitigate against further duplication of DT parsing code. This patch can be used in the following way: struct of_pci_range_parser parser; struct of_pci_range range; if (of_pci_range_parser_init(&parser, np)) ; //no ranges property for_each_of_pci_range(&parser, &range) { /* directly access properties of the address range, e.g.: range.pci_space, range.pci_addr, range.cpu_addr, range.size, range.flags alternatively obtain a struct resource, e.g.: struct resource res; of_pci_range_to_resource(&range, np, &res); */ } Additionally the implementation takes care of adjacent ranges and merges them into a single range (as was the case with powerpc and microblaze). Signed-off-by: Andrew Murray Signed-off-by: Liviu Dudau Signed-off-by: Thomas Petazzoni Reviewed-by: Rob Herring Tested-by: Thomas Petazzoni Tested-by: Linus Walleij Tested-by: Jingoo Han Acked-by: Grant Likely Signed-off-by: Jason Cooper --- diff --git a/drivers/of/address.c b/drivers/of/address.c index 04da786c84d2..fdd0636a987d 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -227,6 +227,73 @@ int of_pci_address_to_resource(struct device_node *dev, int bar, return __of_address_to_resource(dev, addrp, size, flags, NULL, r); } EXPORT_SYMBOL_GPL(of_pci_address_to_resource); + +int of_pci_range_parser_init(struct of_pci_range_parser *parser, + struct device_node *node) +{ + const int na = 3, ns = 2; + int rlen; + + parser->node = node; + parser->pna = of_n_addr_cells(node); + parser->np = parser->pna + na + ns; + + parser->range = of_get_property(node, "ranges", &rlen); + if (parser->range == NULL) + return -ENOENT; + + parser->end = parser->range + rlen / sizeof(__be32); + + return 0; +} +EXPORT_SYMBOL_GPL(of_pci_range_parser_init); + +struct of_pci_range *of_pci_range_parser_one(struct of_pci_range_parser *parser, + struct of_pci_range *range) +{ + const int na = 3, ns = 2; + + if (!range) + return NULL; + + if (!parser->range || parser->range + parser->np > parser->end) + return NULL; + + range->pci_space = parser->range[0]; + range->flags = of_bus_pci_get_flags(parser->range); + range->pci_addr = of_read_number(parser->range + 1, ns); + range->cpu_addr = of_translate_address(parser->node, + parser->range + na); + range->size = of_read_number(parser->range + parser->pna + na, ns); + + parser->range += parser->np; + + /* Now consume following elements while they are contiguous */ + while (parser->range + parser->np <= parser->end) { + u32 flags, pci_space; + u64 pci_addr, cpu_addr, size; + + pci_space = be32_to_cpup(parser->range); + flags = of_bus_pci_get_flags(parser->range); + pci_addr = of_read_number(parser->range + 1, ns); + cpu_addr = of_translate_address(parser->node, + parser->range + na); + size = of_read_number(parser->range + parser->pna + na, ns); + + if (flags != range->flags) + break; + if (pci_addr != range->pci_addr + range->size || + cpu_addr != range->cpu_addr + range->size) + break; + + range->size += size; + parser->range += parser->np; + } + + return range; +} +EXPORT_SYMBOL_GPL(of_pci_range_parser_one); + #endif /* CONFIG_PCI */ /* diff --git a/include/linux/of_address.h b/include/linux/of_address.h index 0506eb53519b..4c2e6f26432c 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -4,6 +4,36 @@ #include #include +struct of_pci_range_parser { + struct device_node *node; + const __be32 *range; + const __be32 *end; + int np; + int pna; +}; + +struct of_pci_range { + u32 pci_space; + u64 pci_addr; + u64 cpu_addr; + u64 size; + u32 flags; +}; + +#define for_each_of_pci_range(parser, range) \ + for (; of_pci_range_parser_one(parser, range);) + +static inline void of_pci_range_to_resource(struct of_pci_range *range, + struct device_node *np, + struct resource *res) +{ + res->flags = range->flags; + res->start = range->cpu_addr; + res->end = range->cpu_addr + range->size - 1; + res->parent = res->child = res->sibling = NULL; + res->name = np->full_name; +} + #ifdef CONFIG_OF_ADDRESS extern u64 of_translate_address(struct device_node *np, const __be32 *addr); extern bool of_can_translate_address(struct device_node *dev); @@ -27,6 +57,11 @@ static inline unsigned long pci_address_to_pio(phys_addr_t addr) { return -1; } #define pci_address_to_pio pci_address_to_pio #endif +extern int of_pci_range_parser_init(struct of_pci_range_parser *parser, + struct device_node *node); +extern struct of_pci_range *of_pci_range_parser_one( + struct of_pci_range_parser *parser, + struct of_pci_range *range); #else /* CONFIG_OF_ADDRESS */ #ifndef of_address_to_resource static inline int of_address_to_resource(struct device_node *dev, int index, @@ -53,6 +88,19 @@ static inline const __be32 *of_get_address(struct device_node *dev, int index, { return NULL; } + +static inline int of_pci_range_parser_init(struct of_pci_range_parser *parser, + struct device_node *node) +{ + return -1; +} + +static inline struct of_pci_range *of_pci_range_parser_one( + struct of_pci_range_parser *parser, + struct of_pci_range *range) +{ + return NULL; +} #endif /* CONFIG_OF_ADDRESS */