On 02/11/2013 02:22 AM, Thierry Reding wrote:
> From: Andrew Murray <andrew.mur...@arm.com>
>
> DT bindings for PCI host bridges often use the ranges property to describe
> memory and IO ranges - this binding tends to be the same across architectures
> yet several parsing implementations exist, e.g. arch/mips/pci/pci.c,
> arch/powerpc/kernel/pci-common.c, arch/sparc/kernel/pci.c and
> arch/microblaze/pci/pci-common.c (clone of PPC). Some of these duplicate
> functionality provided by drivers/of/address.c.
>
> This patch provides a common iterator-based parser for the ranges property, it
> is hoped this will reduce DT representation differences between architectures
> and that architectures will migrate in part to this new parser.
>
> It is also hoped (and the motativation for the patch) that this patch will
> reduce duplication of code when writing host bridge drivers that are supported
> by multiple architectures.
>
> This patch provides struct resources from a device tree node, e.g.:
>
> u32 *last = NULL;
> struct resource res;
> while ((last = of_pci_process_ranges(np, res, last))) {
> //do something with res
> }
>
> Platforms with quirks can then do what they like with the resource or migrate
> common quirk handling to the parser. In an ideal world drivers can just
> request
> the obtained resources and pass them on (e.g. pci_add_resource_offset).
>
> Signed-off-by: Andrew Murray <andrew.mur...@arm.com>
> Signed-off-by: Liviu Dudau <liviu.du...@arm.com>
> Signed-off-by: Thierry Reding <thierry.red...@avionic-design.de>
> ---
> drivers/of/address.c | 63
> ++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/of_address.h | 9 +++++++
> 2 files changed, 72 insertions(+)
>
> diff --git a/drivers/of/address.c b/drivers/of/address.c
> index 04da786..f607008 100644
> --- a/drivers/of/address.c
> +++ b/drivers/of/address.c
> @@ -13,6 +13,7 @@
> #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
>
> static struct of_bus *of_match_bus(struct device_node *np);
> +static struct of_bus *of_find_bus(const char *name);
Can you move this function up to avoid the forward declaration.
> static int __of_address_to_resource(struct device_node *dev,
> const __be32 *addrp, u64 size, unsigned int flags,
> const char *name, struct resource *r);
> @@ -227,6 +228,57 @@ 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);
> +
> +const __be32 *of_pci_process_ranges(struct device_node *node,
> + struct resource *res, const __be32 *from)
> +{
> + const __be32 *start, *end;
> + int na, ns, np, pna;
> + int rlen;
> + struct of_bus *bus;
> +
> + WARN_ON(!res);
> +
> + bus = of_find_bus("pci");
> + bus->count_cells(node, &na, &ns);
> + if (!OF_CHECK_COUNTS(na, ns)) {
> + pr_err("Bad cell count for %s\n", node->full_name);
> + return NULL;
> + }
> +
> + pna = of_n_addr_cells(node);
> + np = pna + na + ns;
> +
> + start = of_get_property(node, "ranges", &rlen);
> + if (start == NULL)
> + return NULL;
> +
> + end = start + rlen / sizeof(__be32);
> +
> + if (!from)
> + from = start;
> +
> + while (from + np <= end) {
> + u64 cpu_addr, size;
> +
> + cpu_addr = of_translate_address(node, from + na);
> + size = of_read_number(from + na + pna, ns);
> + res->flags = bus->get_flags(from);
> + from += np;
> +
> + if (cpu_addr == OF_BAD_ADDR || size == 0)
> + continue;
> +
> + res->name = node->full_name;
> + res->start = cpu_addr;
> + res->end = res->start + size - 1;
> + res->parent = res->child = res->sibling = NULL;
> + return from;
> + }
> +
> + return NULL;
> +}
> +EXPORT_SYMBOL_GPL(of_pci_process_ranges);
> #endif /* CONFIG_PCI */
>
> /*
> @@ -337,6 +389,17 @@ static struct of_bus *of_match_bus(struct device_node
> *np)
> return NULL;
> }
>
> +static struct of_bus *of_find_bus(const char *name)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < ARRAY_SIZE(of_busses); i++)
> + if (strcmp(name, of_busses[i].name) == 0)
^
space needed.
> + return &of_busses[i];
> +
> + return NULL;
> +}
> +
> static int of_translate_one(struct device_node *parent, struct of_bus *bus,
> struct of_bus *pbus, __be32 *addr,
> int na, int ns, int pna, const char *rprop)
> diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> index 0506eb5..751e889 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -27,6 +27,8 @@ static inline unsigned long pci_address_to_pio(phys_addr_t
> addr) { return -1; }
> #define pci_address_to_pio pci_address_to_pio
> #endif
>
> +const __be32 *of_pci_process_ranges(struct device_node *node,
> + struct resource *res, const __be32 *from);
> #else /* CONFIG_OF_ADDRESS */
> #ifndef of_address_to_resource
> static inline int of_address_to_resource(struct device_node *dev, int index,
> @@ -53,6 +55,13 @@ static inline const __be32 *of_get_address(struct
> device_node *dev, int index,
> {
> return NULL;
> }
> +
> +static inline const __be32 *of_pci_process_ranges(struct device_node *node,
> + struct resource *res,
> + const __be32 *from)
> +{
> + return NULL;
> +}
> #endif /* CONFIG_OF_ADDRESS */
>
>
>
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