[PATCH v8 8/9] pci: Add support for creating a generic host_bridge from device tree

Liviu Dudau
2014-07-11T09:08:51Z

On Fri, Jul 11, 2014 at 08:43:21AM +0100, Jingoo Han wrote:
> On Wednesday, July 02, 2014 3:44 AM, Liviu Dudau wrote:
> >
> > Several platforms use a rather generic version of parsing
> > the device tree to find the host bridge ranges. Move the common code
> > into the generic PCI code and use it to create a pci_host_bridge
> > structure that can be used by arch code.
> >
> > Based on early attempts by Andrew Murray to unify the code.
> > Used powerpc and microblaze PCI code as starting point.
> >
> > Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
> > Tested-by: Tanmay Inamdar <tinamdar@apm.com>
> > ---
> > drivers/of/of_pci.c | 135 ++++++++++++++++++++++++++++++++++++++++++++++
> > drivers/pci/host-bridge.c | 18 +++++++
> > include/linux/of_pci.h | 10 ++++
> > include/linux/pci.h | 8 +++
> > 4 files changed, 171 insertions(+)
> >
> > diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c
> > index 8481996..55d8320 100644
> > --- a/drivers/of/of_pci.c
> > +++ b/drivers/of/of_pci.c
>
> [.....]
>
> > +struct pci_host_bridge *
> > +of_create_pci_host_bridge(struct device *parent, struct pci_ops *ops, void *host_data)
> > +{
> > + int err, domain, busno;
> > + struct resource *bus_range;
> > + struct pci_bus *root_bus;
> > + struct pci_host_bridge *bridge;
> > + resource_size_t io_base;
> > + LIST_HEAD(res);
> > +
> > + bus_range = kzalloc(sizeof(*bus_range), GFP_KERNEL);
> > + if (!bus_range)
> > + return ERR_PTR(-ENOMEM);
> > +
> > + domain = of_alias_get_id(parent->of_node, "pci-domain");
> > + if (domain == -ENODEV)
> > + domain = atomic_inc_return(&domain_nr);
> > +
> > + err = of_pci_parse_bus_range(parent->of_node, bus_range);
> > + if (err) {
> > + dev_info(parent, "No bus range for %s, using default [0-255]\n",
> > + parent->of_node->full_name);
> > + bus_range->start = 0;
> > + bus_range->end = 255;
> > + bus_range->flags = IORESOURCE_BUS;
> > + }
> > + busno = bus_range->start;
> > + pci_add_resource(&res, bus_range);
> > +
> > + /* now parse the rest of host bridge bus ranges */
> > + err = pci_host_bridge_of_get_ranges(parent->of_node, &res, &io_base);
> > + if (err)
> > + goto err_create;
> > +
> > + /* then create the root bus */
> > + root_bus = pci_create_root_bus_in_domain(parent, domain, busno,
> > + ops, host_data, &res);
> > + if (IS_ERR(root_bus)) {
> > + err = PTR_ERR(root_bus);
> > + goto err_create;
> > + }
> > +
> > + bridge = to_pci_host_bridge(root_bus->bridge);
> > + bridge->io_base = io_base;
>
> Hi Liviu Dudau,
>
> Would you fix the following warning?
>
> drivers/of/of_pci.c: In function 'of_create_pci_host_bridge'
> drivers/of/of_pci.c:218:18: warning: 'of_base' may be used uninitialized in this function [-Wmaybe-uninitialized]
> bridge->io_base = io_base;

Yes, I have a simple fix which is to set the initial value to zero when declaring the variable.

Best regards,
Liviu

>
> Best regards,
> Jingoo Han
>
> [.....]
>
>

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