On Wed, Dec 12, 2012 at 04:37:50PM +0000, Andrew Murray wrote:
> 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.Murray@xxxxxxx>
> Signed-off-by: Liviu Dudau <Liviu.Dudau@xxxxxxx>
> ---
> drivers/of/address.c | 53 +++++++++++++++++++++++++++++++++++++++++++-
> include/linux/of_address.h | 7 +++++
> 2 files changed, 59 insertions(+), 1 deletions(-)
Hi Andrew,
I don't like iterator interfaces too much, but I can live with that.
Other than that the patch looks good to me and I'll try to work it into
my Tegra PCIe patch series.
Just two minor comments below.
> diff --git a/drivers/of/address.c b/drivers/of/address.c
[...]
> @@ -421,7 +472,7 @@ u64 __of_translate_address(struct device_node *dev, const __be32 *in_addr,
> goto bail;
> bus = of_match_bus(parent);
>
> - /* Cound address cells & copy address locally */
> + /* Count address cells & copy address locally */
> bus->count_cells(dev, &na, &ns);
> if (!OF_CHECK_COUNTS(na, ns)) {
> printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
This is really minor, but it should still go into a separate patch.
> diff --git a/include/linux/of_address.h b/include/linux/of_address.h
> index 01b925a..4582b20 100644
> --- a/include/linux/of_address.h
> +++ b/include/linux/of_address.h
> @@ -26,6 +26,8 @@ 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 */
> static inline int of_address_to_resource(struct device_node *dev, int index,
> struct resource *r)
> @@ -48,6 +50,11 @@ static inline const u32 *of_get_address(struct device_node *dev, int index,
> {
> return NULL;
> }
> +const __be32 *of_pci_process_ranges(struct device_node *node,
There should be a blank line to separate the above two lines.
Thierry
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